Persistência do vítreo primário hiperplásico e catarata em cão / Persistence of hyperplastic primary vitreous and cataract in a dog

Background: Persistent hyperplastic primary vitreous is a rare ocular condition that is usually unilateral, formed when normal regression of the hyaloid vascular system does not occur. Diagnosis is possible through ultrasonography, by obtaining images that provide information and also serve as a differential diagnosis. Clinically the condition presents with signs of leukocoria, microphthalmia, and cataracts, and it can be further classified into 6 degrees according to the evolution. The objective of this work is to describe the case and treatment of a canine of the Pointer breed that presented opacity in both eyes, with diagnosis confirmed through ocular ultrasonography. Case: A 6-year-old male pointer dog, weighing 27 kg, was referred to the Veterinary Medical Teaching Hospital of the Federal University of Santa Maria (UFRGS), Santa Maria, RS - Brazil with a history of blindness. According to the owner, the animal's right eye has always been "white", since it was a puppy and the left eye began to present the same characteristic a short time ago. On ophthalmological examination, neither eye showed signs of ocular discomfort, the Schirmer's tear test was within the range expected for the species, fluorescein and threat tests were negative, and a positive pupillary reflex was observed in the left eye. The right eye had total corneal opacity associated with a chronic lesion and the presence of pigment cells in the medial portion of the eyeball, the opacity making it impossible to visualize the other internal structures of the eyeball. The left eye presented lens opacity. In the ultrasound of the right eye, there were several alterations, the presence of a triangular-shaped hyperechogenic structure in the vitreous chamber, a decrease in the depth of the anterior chamber, and the presence of abnormality in the development of the lens. The findings are compatible with and confirmed the diagnosis of PHPV. In the left eye, the ultrasound images indicated hyperechogenicity of the posterior and anterior poles of the lens, findings compatible with cataracts. Through the animal's history, complete ophthalmic examination, and use of ocular ultrasonography, it was possible to diagnose and differentiate the causes of the white eye in the patient. The preoperative screening was continued with an electroretinography examination, which showed a satisfactory electrical response for the retina of the left eye and an unsatisfactory electrical response for the retina of the right eye. Phacoemulsification surgery was performed to remove the cataract in the left eye with intraocular lens implantation. The positive threat reflex returned in this eye, with a return of visual acuity. Discussion: Persistent hyperplastic tunica lentis and persistent hyperplastic primary vitreous (PHTVL/PHPV) are congenital anomalies caused by a failure to regress the fetal hyaloid vasculature. These conditions are not common, but occur sporadically in dogs. The PHPV classification can be classified into degrees, based on the morphological aspect of the lesion. Following this classification scheme, the PHPV of the animal in question refers to the 6th degree of evolution. The total opacity of the cornea in the right eye was associated with the presence of a hyperplastic primary vitreous and the leukocoria in the left eye was due to the presence of a mature cataract. The conclusion of the diagnosis was only possible through ocular ultrasonography, which is very useful to differentiate the causes of ocular opacity and leukocoria, in addition to allowing complete evaluation of the intraocular structures and being considered an essential exam to confirm the diagnosis of PHPV.

Anoftalmia bilateral em cão associada à malformação peniana congênita / Bilateral anophthalmia in dog associated with congenital penile malformation

Background: Anophthalmia refers to the complete absence of an eyeball. It is a very rare congenital condition that affects all breeds of dogs, which may be unilateral or bilateral. Anophthalmia results from a severe developmental deficiency in the primitive forebrain, prior to the formation of the optic sulcus. This condition has a complex etiology, and chromosomal, monogenic, and environmental causes have already been identified. There might be an association between anophthalmia and other congenital abnormalities. This case report aimed to report the case of a male dog with bilateral anophthalmia associated with penile malformation. Case: A 3-year-old male mongrel dog was evaluated in a clinical consultation at the Veterinary Medical Teaching Hospital of the Federal University of Piauí (UFPI) - Teresina - Brazil, with signs of anemia and diarrhea. His vaccinations were not up to date (multiple and anti-rabies), presented ectoparasites (ticks), and showed inappetence. The owner reported that the animal was blind from birth, was already well adapted to its environment, had the company of other animals, and had no access to the street. On clinical examination, the animal had a good body score. The eyelids were bilaterally present with normally developed eyelashes. Both the head and face had a symmetrical appearance, without structural abnormalities, and the palpebral fissures were narrow. When opening the eyelids manually, the presence of the conjunctiva was observed bilaterally, the orbits were shallow, and neither orbit contained the eyeball. Further inspection with an ophthalmic clinical flashlight did not reveal any other ocular structures. The initial diagnosis was suggestive of bilateral anophthalmia. Ultrasound examination of the ocular region confirmed the presence of bilateral anophthalmia. A general physical examination revealed a malformed penis with a persistent penile frenulum. Regarding systemic clinical signs (apathy, inappetence, diarrhea, and anemia), clinical and laboratory examinations led to the suspicion of verminosis. Discussion: The dog in this report had a good body score; however, this type of malformation can generate non-viable puppies. Anophthalmia is an extremely rare congenital ocular malformation, both in humans and companion animals, in which there are no ocular structures in the orbits, and these structures (orbits) in affected individuals are generally small and shallow, as seen in the dog in this report. Ultrasonographic examination confirmed the bilateral anophthalmic condition, being the most accurate method of diagnosing this congenital condition. The animal in this report presented with anophthalmia associated with penile malformation. This type of association until this case report has only been described in humans and mice, and is probably caused by a mutation in the SOX2 gene, which is responsible for the protein of the same name, which makes the maturation of ocular tissues in the primitive forebrain. Thus, it is likely that such congenital alterations are the cause of the malformations observed in this animal. Maternal vitamin A deficiency, a factor known to cause ocular malformations, may also be involved in the etiology of congenital diseases. Nutritional imbalances in dogs are common in the animal's region of origin The dog in this report had a normal life. Although it is a condition that causes blindness, dogs can have a normal life and welfare, even with bilateral anophthalmia.

Influence of plants used in agricultural diversification on the nematode Heterorhabditis amazonensis / Influência de plantas utilizadas na diversificação agrícola sobre o nematoide Heterorhabditis amazonensis

In an agricultural system, to increase natural biological control, plants that attract natural enemies can be grown alongside the main crop. However, the effects of these plants on entomopathogenic nematodes (EPNs), important agents for controlling soil pests, and the action of their conservation are unknown. To assess the impact of these plants on EPNs, two experiments were carried out in a greenhouse. The first measured the effect of Crotalaria spectabilis, Crotalaria breviflora, and Tagetes erecta on the persistence and infectivity of Heterorhabditis amazonensis isolate RSC 5 for 27 days, compared to a control treatment without plants. The second trial evaluated the effect of C. breviflora and T. erecta on the displacement of the nematode. Additionally, the influence of predator Calosoma granulatum in this system was evaluated. The plants did not influence nematode behaviour in terms of persistence, infectivity, or displacement. However, C. spectabilis allowed the most significant persistence of nematodes in the substrate for a short time, and T. erecta caused the fastest suppression of the initial population of infectives juvenile. In the second experiment, neither the predator nor the plants affected the nematode's ability to move in the soil within 5 days. These results show that prior knowledge in agricultural diversification can help to control pests by inundative application of EPNs.(AU)

Em um sistema agrícola, a fim de aumentar o controle biológico natural, plantas que atraem inimigos naturais podem ser cultivadas junto à cultura principal. Porém, os efeitos destas plantas sobre nematoidesentomopatogênicos (NEPs), importante agentes de controle de pragas de solo, e sua ação na conservação destes, são desconhecidos. Com o objetivo de avaliar o efeito de algumas destas plantas sobre NEPs, foram montados dois experimentos em casa-de-vegetação. O primeiro observou o efeito das plantas Crotalaria spectabilis, Crotalaria breviflora e Tagetes erecta sobre a persistência e infectividade de Heterorhabditis amazonensis isolado RSC 5 durante 27 dias, comparadas a um tratamento-controle sem plantas. Já o segundo experimento avaliou o efeito de C. breviflora e T. erecta, com a presença ou não do adulto do predador Calosoma granulatum no deslocamento do nematoide. Os resultados indicaram que as plantas não influenciaram na persistência dos nematoides em longo prazo nem na infectividade e no deslocamento de H. amazonensis. Porém, a planta C. spectabilis possibilitou a maior persistência de nematoides no substrato em curto prazo, e T. erecta causou a supressão mais rápida da população inicial de JIs. No segundo experimento observou-se que nem a presença do predador e das plantas afetou a capacidade de deslocamento do nematoide no solo no período de 5 dias. Estes resultados mostram que o conhecimento prévio das plantas a serem utilizadas na diversificação agrícola pode auxiliar no controle inundativo de pragas por NEPs.(AU)

Detoxified castor in the diets of dairy goats: II. Lactation curves, composition, and fatty acid profile of milk

We aimed to evaluate the lactation curves, composition, and fatty acid profile of milk of lactating goats fed diets containing detoxified castor cake (DCC) by alkaline solutions during 150 days of lactation. Twenty-four Saanen and Anglo Nubian goats, approximately 17 months old (first lactation) and 43±2.97 kg body weight, were distributed in a completely randomized block design with eight replicates. Treatments consisted of three diets, one containing soybean meal (SM) and two others containing DCC, with calcium hydroxide [Ca(OH)2] and sodium hydroxide (NaOH). The lactation curves showed greater persistence of lactation in Saanen goats. There were significant effects of diets on the profile of some fatty acids present in the milk. We observed that the NaOH DCC diet led to an increase in desirable fatty acid content. Both Ca(OH)2 and NaOH DCC diets led to decreased milk production during the lactation period; however, the NaOH DCC diet led to high productive efficiency. Furthermore, NaOH DCC did not negatively affect the desirable fatty acid content, unlike Ca(OH)2 DCC. Diets formulated with detoxified castor decrease the production of milk from goats during lactation phase. It should be emphasized that milk produced by goats fed DCC diets does not contain unwanted waste.(AU)

Detoxified castor in the diets of dairy goats: I. Effects on intake, digestibility, and renal and hepatic parameters

The objective was to evaluate the intake, digestibility, nitrogen balance, and metabolic profile of lactating goats fed diets containing detoxified castor cake (DCC) by alkaline solutions during 150 days of lactation. Twenty-four Saanen and Anglo Nubian goats, approximately 17 months old (first lactation) and body weights of 43±2.97 kg, were distributed in a completely randomized block design with eight replicates. Treatments consisted of three diets, one containing soybean meal (SM) and two others containing DCC, with calcium hydroxide [Ca(OH)2] and sodium hydroxide (NaOH). The diets significantly influenced the intake of dry matter (DM), crude protein (CP), ether extract (EE), neutral detergent fiber (NDF), and total digestible nutrients (TDN). We observed a higher dry matter intake (DMI) in goats fed SM, similar to that of goats fed Ca(OH)2 DCC. Intake of nutrients followed the same trend as DMI. There was no significant effect of diets on digestibility of DM, CP, EE, and NDF; however, we observed a significant effect of diets on the levels of nitrogen intake (NI) and urinary nitrogen (UN). The goats fed SM consumed a larger quantity of nitrogen, but all had the same nitrogen balance, indicating that goats fed DCC were more efficient. The diets did not influence renal and hepatic parameters. Inclusion of castor cake in the diet of goats in confinement is an attractive option, considering that goats fed DCC present lower feed conversion, and its use does not cause hepatic and renal alterations, suggesting that SM can be completely replaced.(AU)

Seleção de espécies tolerantes para a fitorremediação de solo contaminado com imazapic / Selection of tolerant species for contaminated soil phytemedication using imazapic

O imazapic por apresentar longo efeito residual no solo pode ocasionar intoxicação visual em culturas sensíveis semeadas em rotação, além de representar riscos ecotoxicológicos em ambientes aquáticos. Diante disso, a fitorremediação é uma proposta inovadora como método alternativo para a remoção de poluentes orgânicos, sendo o sucesso da técnica dependente da seleção criteriosa de plantas com características favoráveis. O objetivo do estudo foi de identificar espécies de plantas tolerantes ao imazapic para potencial uso em programas de fitorremediação. Foram conduzidos oito experimentos em casa de vegetação climatizada com as espécies, Panicum maximum, Crotalaria juncea, Stylosanthes spp., Cajanus cajan, Dolichos lablab, Pennisetum glaucum, Mucuna aterrima, Raphanus sativus e cinco doses de imazapic (0; 58,33; 87,5; 175 e 350 g ha-1). Os tratamentos foram delineados em blocos ao acaso com quatro repetições. Aos 30 e 60 dias após a emergência das plantas foram avaliados os sintomas de intoxicação visual, altura e a massa seca das plantas, determinada ao término do experimento. As espécies M. aterrima, C. cajan e D. lablab não apresentaram sintomas visuais de fitointoxicação. M. aterrima foi a que promoveu maior produção de massa seca quando cultivada como testemunha e a exposição ao imazapic pouco afetou essa característica. Nas espécies tolerantes, a redução da altura e massa...

Imazapic can cause visual intoxication in sensitive crops sown in rotation given its long residual effect in the soil and represents ecotoxicological risks in aquatic environments. In this scenario, phytoremediation is an innovative proposal as an alternative method for removing organic pollutants, with its success depending on the careful selection of plants with favorable characteristics. The objective of this study was to identify imazapic-tolerant plant species for potential use in phytoremediation programs. Eight experiments were conducted in a greenhouse using the species Panicum maximum, Crotalaria juncea, Stylosanthes spp., Cajanus cajan, Dolichos lablab, Pennisetum glaucum, Mucuna aterrima, and Raphanus sativus, considering five doses of imazapic (0; 58.33; 87.5; 175 and 350 g ha-1). The treatments were delineated in randomized blocks with four replicates. The symptoms of visual toxicity, height, and dry mass of the plants were determined at 30 and 60 days after plant emergence and at the end of the experiment. The species M. aterrima, C. cajan, and D. lablab presented no visual symptoms of phyto-intoxication. M. aterrima promoted greater dry mass production when cultivated as a control, and exposure to imazapic did not affect this characteristic. Height and dry mass reduction required higher doses in tolerant species, although the results were not significant for...

Pupillary membrane persistence in a feline

Background: Pupillary membrane persistence (PMP) is a congenital abnormality, which is not usually reported in felines.It is characterized by remnants of the fetal membrane that persist as filamentous tissue across the pupil. In general, thischange does not cause any clinical signs. However, the filaments may either attach to the cornea and cause small opacitiesin it or attach to the lens and cause cataracts. In most cases, there is no visual impairment, so treatment is not required.This report aims to describe a case of PMP in a domestic cat diagnosed at the Veterinary Hospital of the State Universityof Santa Cruz (HV-UESC).Case: A two-and-a-half-year-old mixed-breed castrated male cat was brought to the HV-UESC with dermatological complaints. Upon physical examination, the animal was alert with a body temperature, heart, and respiratory rate within thenormal parameters for the feline species. The lymph nodes were non-reactive, and the coloration of the oral mucosa wasnormal. There was no ophthalmic complaint from the owner, nor any loss of visual acuity. In addition, the animal hadmoderate pruritus, redness, and alopecia in the region of the ears, head, neck, chest, and back. Bristle samples were collected for an optical microscope analysis and an infestation with lice (Felicola subrostratus) was confirmed. An endectocidecontaining selamectin (15 mg; single application every 30 days) was prescribed. During physical examination, filamentoustissue crossing from iris to iris through pupil was observed in both eyes. The eyelid, corneal, and pupillary reflexes werewithin normal ranges. An ophthalmic evaluation did not identify conjunctival hyperemia or episcleral vessel congestion,and the eyelid, corneal, and pupillary reflexes were determined to be within the normal range. A slit-lamp biomicroscopydid not detect any anterior chamber alteration besides the filamentous tissue previously mentioned...

Seleção de espécies tolerantes para a fitorremediação de solo contaminado com imazapic / Selection of tolerant species for contaminated soil phytemedication using imazapic

O imazapic por apresentar longo efeito residual no solo pode ocasionar intoxicação visual em culturas sensíveis semeadas em rotação, além de representar riscos ecotoxicológicos em ambientes aquáticos. Diante disso, a fitorremediação é uma proposta inovadora como método alternativo para a remoção de poluentes orgânicos, sendo o sucesso da técnica dependente da seleção criteriosa de plantas com características favoráveis. O objetivo do estudo foi de identificar espécies de plantas tolerantes ao imazapic para potencial uso em programas de fitorremediação. Foram conduzidos oito experimentos em casa de vegetação climatizada com as espécies, Panicum maximum, Crotalaria juncea, Stylosanthes spp., Cajanus cajan, Dolichos lablab, Pennisetum glaucum, Mucuna aterrima, Raphanus sativus e cinco doses de imazapic (0; 58,33; 87,5; 175 e 350 g ha-1). Os tratamentos foram delineados em blocos ao acaso com quatro repetições. Aos 30 e 60 dias após a emergência das plantas foram avaliados os sintomas de intoxicação visual, altura e a massa seca das plantas, determinada ao término do experimento. As espécies M. aterrima, C. cajan e D. lablab não apresentaram sintomas visuais de fitointoxicação. M. aterrima foi a que promoveu maior produção de massa seca quando cultivada como testemunha e a exposição ao imazapic pouco afetou essa característica. Nas espécies tolerantes, a redução da altura e massa...(AU)

Imazapic can cause visual intoxication in sensitive crops sown in rotation given its long residual effect in the soil and represents ecotoxicological risks in aquatic environments. In this scenario, phytoremediation is an innovative proposal as an alternative method for removing organic pollutants, with its success depending on the careful selection of plants with favorable characteristics. The objective of this study was to identify imazapic-tolerant plant species for potential use in phytoremediation programs. Eight experiments were conducted in a greenhouse using the species Panicum maximum, Crotalaria juncea, Stylosanthes spp., Cajanus cajan, Dolichos lablab, Pennisetum glaucum, Mucuna aterrima, and Raphanus sativus, considering five doses of imazapic (0; 58.33; 87.5; 175 and 350 g ha-1). The treatments were delineated in randomized blocks with four replicates. The symptoms of visual toxicity, height, and dry mass of the plants were determined at 30 and 60 days after plant emergence and at the end of the experiment. The species M. aterrima, C. cajan, and D. lablab presented no visual symptoms of phyto-intoxication. M. aterrima promoted greater dry mass production when cultivated as a control, and exposure to imazapic did not affect this characteristic. Height and dry mass reduction required higher doses in tolerant species, although the results were not significant for...(AU)

Pupillary membrane persistence in a feline

Background: Pupillary membrane persistence (PMP) is a congenital abnormality, which is not usually reported in felines.It is characterized by remnants of the fetal membrane that persist as filamentous tissue across the pupil. In general, thischange does not cause any clinical signs. However, the filaments may either attach to the cornea and cause small opacitiesin it or attach to the lens and cause cataracts. In most cases, there is no visual impairment, so treatment is not required.This report aims to describe a case of PMP in a domestic cat diagnosed at the Veterinary Hospital of the State Universityof Santa Cruz (HV-UESC).Case: A two-and-a-half-year-old mixed-breed castrated male cat was brought to the HV-UESC with dermatological complaints. Upon physical examination, the animal was alert with a body temperature, heart, and respiratory rate within thenormal parameters for the feline species. The lymph nodes were non-reactive, and the coloration of the oral mucosa wasnormal. There was no ophthalmic complaint from the owner, nor any loss of visual acuity. In addition, the animal hadmoderate pruritus, redness, and alopecia in the region of the ears, head, neck, chest, and back. Bristle samples were collected for an optical microscope analysis and an infestation with lice (Felicola subrostratus) was confirmed. An endectocidecontaining selamectin (15 mg; single application every 30 days) was prescribed. During physical examination, filamentoustissue crossing from iris to iris through pupil was observed in both eyes. The eyelid, corneal, and pupillary reflexes werewithin normal ranges. An ophthalmic evaluation did not identify conjunctival hyperemia or episcleral vessel congestion,and the eyelid, corneal, and pupillary reflexes were determined to be within the normal range. A slit-lamp biomicroscopydid not detect any anterior chamber alteration besides the filamentous tissue previously mentioned...(AU)

Potencial leiteiro de animais da raça Pantaneira na região do Alto Pantanal do Mato Grosso do Sul / Dairy potential of pantaneira breed upper region of pantanal of Mato Grosso Sul

The Pantaneira breed is in danger of extinction. Due to the lack of scientific information on the Pantanal milk potential, this work had the objective of determining the lactation period and a physical-chemical composition of the milk of cows in second order of parturition. The animals were managed in a pasture system rotated in mombaça grass (Panicum maximum) and individually supplemented with concentrate. The milking was performed mechanically twice a day and the milk weighed daily. The physical-chemical characteristics of the milk were evaluated by the ultrasound method and the lactation curves were estimated using the univariate parameter. The average milk yield was 5.34kg/milk/ day and the fat, protein, lactose and total non-fat solids contents were 5.3, 3.7, 6.0 and 10.7%, respectively. Lactation of the cows in second order of calving ended naturally at 180 days and the peak of milk production was reached between 51 and 60 days. Furthermore, there was no difference in milk composition in the different lactation periods.(AU)

Potencial leiteiro de animais da raça Pantaneira na região do Alto Pantanal do Mato Grosso do Sul / Dairy potential of pantaneira breed upper region of pantanal of Mato Grosso Sul

The Pantaneira breed is in danger of extinction. Due to the lack of scientific information on the Pantanal milk potential, this work had the objective of determining the lactation period and a physical-chemical composition of the milk of cows in second order of parturition. The animals were managed in a pasture system rotated in mombaça grass (Panicum maximum) and individually supplemented with concentrate. The milking was performed mechanically twice a day and the milk weighed daily. The physical-chemical characteristics of the milk were evaluated by the ultrasound method and the lactation curves were estimated using the univariate parameter. The average milk yield was 5.34kg/milk/ day and the fat, protein, lactose and total non-fat solids contents were 5.3, 3.7, 6.0 and 10.7%, respectively. Lactation of the cows in second order of calving ended naturally at 180 days and the peak of milk production was reached between 51 and 60 days. Furthermore, there was no difference in milk composition in the different lactation periods.(AU)

Growth, viability and architecture of biofilms of Listeria monocytogenes formed on abiotic surfaces

The pathogenic bacterium Listeria monocytogenes can persist in food processing plants for many years, even when appropriate hygienic measures are in place, with potential for contaminating ready-to-eat products and, its ability to form biofilms on abiotic surfaces certainly contributes for the environmental persistence. In this research, L. monocytogenes was grown in biofilms up 8 days attached to stainless steel and glass surfaces, contributing for advancing the knowledge on architecture of mature biofilms, since many literature studies carried out on this topic considered only early stages of cell adhesion. In this study, biofilm populations of two strains of L. monocytogenes (serotypes 1/2a and 4b) on stainless steel coupons and glass were examined using regular fluorescence microscopy, confocal laser scanning microscopy and classic culture method. The biofilms formed were not very dense and microscopic observations revealed uneven biofilm structures, with presence of exopolymeric matrix surrounding single cells, small aggregates and microcolonies, in a honeycomb-like arrangement. Moreover, planktonic population of L. monocytogenes (present in broth media covering the abiotic surface) remained stable throughout the incubation time, which indicates an efficient dispersal mechanism, since the culture medium was replaced daily. In conclusion, even if these strains of L. monocytogenes were not able to form thick multilayer biofilms, it was noticeable their high persistence on abiotic surfaces, reinforcing the need to focus on measures to avoid biofilm formation, instead of trying to eradicate mature biofilms.(AU)

Clonalidade e perfis de resistência a antibióticos em Yersinia enterocolitica de suínos e humanos no Brasil

Yersinia enterocolitica é um patógeno associado usualmente a produtos derivados de suínos, seu principal reservatório. Esse patógeno é frequentemente isolado em tecidos linfáticos de suínos, em especial tonsilas palatinas e linfonodos mesentéricos. Por estar intimamente associada a cadeia produtiva de suínos, Y. enterocolitica está sujeita a todos os efeitos derivados dos procedimentos de manejo usualmente aplicados aos animais, como o desenvolvimento de resistência devido a aplicação preventiva ou terapêutica de antibióticos. Em um estudo prévio de nosso grupo, Y. enterocolitica foi identificada em uma cadeia produtiva de suínos e os isolados apresentaram alta similaridade de seus perfis de macro-restrição por XbaI. Assim, esse estudo teve como objetivo avaliar a persistência de Y. enterocolitica nessa cadeia produtiva de suínos, além de verificar a similaridade e potencial clonalidade dos isolados do bio-sorotipo 4/O:3 com isolados obtidos de casos de yersiniose humana, além de seus perfis de resistência a antibióticos. Amostras de tonsilas palatinas (n = 100), palatos (n = 30) e carne de cabeça (n = 17) foram obtidas durante o abate de suínos provenientes da mesma cadeia produtiva de suínos em que o estudo prévio de nosso grupo foi conduzido; as amostras foram submetidas a pesquisa de Y. enterocolitica, e os isolados obtidos submetidos a identificação de seus bio-sorotipos, pesquisa de genes de virulência (ail, ystB, virF, myfA, ystA, ystC, fepA, fepD, fes, tccC, ymoA, hreP e sat) e resistência múltipla a antibióticos (emrD, yfhD e marC). Parte desses isolados (n = 24) e isolados obtidos no estudo anterior de nosso grupo (n = 13) foram selecionados e caracterizados quanto aos seus perfis de macro-restrição com XbaI e NotI. Entre as amostras analisadas, 14 (9,5%) foram positivas para Y. enterocolitica, e os isolados obtidos (n = 24) foram identificados como pertencentes ao bio-sorotipo 4/O:3. Todos os isolados apresentaram resultados positivos para os genes de virulência e resistência múltipla a antibióticos pesquisados. Os isolados selecionados apresentaram alta similaridade após análise de seus perfis de macro-restrição, sendo agrupados em dois clusters com 33 (similaridade entre 82,4 e 100,0%) e 4 (similaridade entre 83,3 e 100,0%) isolados. Em seguida, parte desses isolados (n = 24) e isolados de Y. enterocolitica 4/O:3 obtidos de casos de yersiniose humana (n = 3) foram submetidos a sequenciamento completo de seus genomas e análises de similaridade, além de serem caracterizados quanto aos seus perfis de resistência a antibióticos pelo método de difusão em disco (14 antibióticos). Pela análise de polimorfismo de nucleotídeo único (SNP), os isolados foram agrupados em dois grandes clados, sendo apenas um isolado (R31) no Clado A e os demais no Clado B, e um total de sete grupos clonais. As diferenças marcantes observadas no genoma do isolado R31 foram determinadas pela presença de vários genes associados a fagos, o que determinou a sua identificação como pertencente ao sorotipo O:5. Treze isolados apresentaram resistência a antibióticos de três ou mais classes, sendo caracterizados como multidroga resistentes. A análise dos genomas dos isolados permitiu a identificação de 17 genes associados a resistência a antibióticos. A maioria dos isolados apresentou resistência a cefalosporinas, porém sem a presença de genes correspondentes a esse grupo de antibiótico. O estudo permitiu identificar a persistência de Y. enterocolitica do bio-sorotipo 4/O:3 na cadeia produtiva de suínos analisada, além de uma alta similaridade genética entre isolados obtidos nessa cadeia produtiva com isolados obtidos de casos de yersiniose humana, confirmando a relevância de suínos na manutenção e transmissão desse patógeno.

Yersinia enterocolitica is a foodborne pathogen usually associated to pork products, once pigs are their main reservoirs. This pathogen is often isolated from swine lymphatic tissues, especially tonsils and mesenteric lymph-nodes. Once it is close related to swine production, Y. enterocolitica is subjected to all effects resulted from the usual handling of pigs, such as the developing of antibiotic resistance as a consequence of preventive or therapeutic use of antimicrobials. Y. enterocolitica was previously identified by our group in a swine production chain and the obtained isolates presented high matching of band profiles after macro-restriction with XbaI. Thus, this study we aimed to evaluate the persistence of Y. enterocolitica in this swine production chain, the genetic similarity and potential clonality of the bio-serotype 4/O:3 isolates from this production chain with human yersiniosis isolates and their antibiotic resistance profiles. Samples of palatine tonsils (n = 100), palates (n = 30) and head meat (n = 17) were obtained from slaughtered pigs from the same production chain included in our previous study; samples were subjected to isolation of Y. enterocolitica and the isolates subjected to identification of their bio-serotypes, research of virulence genes (ail, ystB, virF, myfA, ystA, ystC, fepA, fepD, fes, tccC, ymoA, hreP and sat) and multidrug resistance related genes (emrD, yfhD and marC). A subset of these isolates (n = 24) and isolates obtained in our previous study (n = 13) were selected and characterized based on their band profiles after macro-restriction with XbaI and NotI. Y. enterocolitica was isolated in 14 (9.5%) of the analyzed samples, and the obtained isolates (n = 24) were identified as bio-serotype 4/O:3. All isolates presented the researched virulence and multidrug resistance related genes. The selected isolates presented high band matching after macro-restriction analysis, being grouped in two clusters with 33 (82.4 to 100.0% of band matching) and 4 (83.3 to 100.0% band matching) isolates. Then, a subset of these isolates (n = 24) and Y. enterocolitica 4/O:3 isolates obtained from human yersiniosis (n = 3) were subjected to whole genome sequencing, checked for genetic similarity and antibiotic resistance through the disk diffusion assay (14 antibiotics). Based on Single Nucleotide Polymorphism (SNP) analysis, isolates were grouped in two major clades: a single isolate (R31) was included in Clade A and other in Clade B, with a total of seven clonal groups. R31 presented several phage related genes, explaining its genetic differences when compared to other isolates. Thirteen isolates were characterized as multidrug resistant, once they presented resistance to three or more antibiotic classes. Genome analysis revealed the presence of 17 antibiotic resistance related genes among Y. enterocolitica isolates, and most of the isolates presented resistance to cephalosporins, despite the absence of the related genes. We were able to demonstrate the persistence of Y. enterocolitica 4/O:3 in the studied swine production chain, despite a high genetic similarity among the obtained isolates and human yersiniosis isolates, confirming the relevance of the swine in the maintenance and transmission of this pathogen.

Tifton 85 grass responses to different nitrogen levels and cutting intervals / Características estruturais e composição bromatológica de capim tifton 85 sob doses de nitrogênio e idades de rebrota

The objective of this study was to evaluate the influence of five levels of N and two regrowth intervals on the structural, productive, and nutritional characteristics of Tifton 85 grass (Cynodon spp). The experiment was conducted in a hay production field at the State University of West Paraná, planted in 2004 with Cynodon spp. cv. Tifton 85. The experiment was established in a randomized block design with factorial treatments of five N fertilization amounts (0, 25, 50, 75 and 100 kg ha-1 cut-1) applied as urea after each cut, and two regrowth intervals (28 and 35 d), with four replicates. N application promoted changes in plant structure, such as increased canopy height, stem length, leaf elongation rate, and dry mass (DM) production. The greatest N use efficiency, considering the four harvests, occurred in the plot with 25 kg N ha-1 cut-1 at the 35-d interval, with a production of 13.79 kg DM kg-1 of N applied. A nutritional analysis indicated that 100 kg ha-1 of N cut-1 promoted higher crude protein (CP) at 28 d, with the highest concentration observed in the fourth cut (208.2 g kg-1 DM) and the lowest in the second cut (140.12 g kg-1 DM). The content average in the four cuts for CP and LIG at 28 days of regrowth was 175.85 and 104.33 kg-1 g MS and at 35 days of regrowth interval was of 164.45 and 118.65 g kg-1 DM, respectively. No differences were found between regrowth in

O objetivo do trabalho foi avaliar a influência de cinco doses de nitrogênio (N) em duas idades de rebrota no capim Tifton 85 (Cynodon spp.) sobre as características estruturais, produtivas e na composição bromatológica. O experimento foi instalado no campo de produção de feno da UNIOESTE, campus de Marechal Cândido Rondon. O delineamento experimental foi em blocos casualizados em esquema fatorial 5x2, sendo cinco doses de nitrogênio (0, 25, 50, 75 e 100 kg ha-1) aplicados em cada corte, aplicadas na forma de uréia, duas idades de rebrota (28 e 35 dias) com quatro repetições e quatro cortes. As doses de nitrogênio promoveram alterações nas características estruturais das plantas, como maior altura do dossel, comprimento de colmo, taxa de alongamento das folhas e produção de MS. A maior eficiência de utilização de N ocorreu na dose de 25 kg N ha-1 corte-1, com 13,79 kg de MS kg-1 de N aplicado na idade de rebrota de 35 dias. Na composição bromatológica a dose de 100 kg N ha-1 corte-1 promoveu maior teor de proteína bruta na idade de 28 dias, sendo que a maior concentração ocorreu no quarto corte (208,2 g kg-1 MS) e a menor no segundo corte (140,12 g kg-1 MS). Os teores médios considerando os quatro cortes de proteína bruta e lignina foram de 175,85 e 104,33 g kg-1 MS aos 28 dias e de 164,45 e 118,65 g kg-1 MS aos 35 dias de intervalo de corte, respectivamente. Não houve diferenç

ASSOCIAÇÕES GENÉTICAS ENTRE PRODUÇÃO DE LEITE, PORCENTAGENS DE SÓLIDOS E FERTILIDADE EM VACAS DA RAÇA HOLANDESA

A tese teve como objetivos: (I) determinar modelos adequados que expliquem a curva de lactação e porcentagens de sólidos nas três primeiras lactações de vacas Holandesas, (II) avaliar como os efeitos de região, estação do parto e ordem de lactação interagem de maneira a alterar a curva de lactação em vacas da raça Holandesa, (III) estimar os parâmetros genéticos para as características da curva de lactação e avaliação da persistência de lactação empregando modelos de regressão aleatória em vacas da raça Holandesa, (IV) estimar a associação genética entre a produção de leite e características de fertilidade em vacas primíparas da raça Holandesa e (V) estimar a associação genética entre a relação gordura:proteína, produção de leite e fertilidade em animais da raça Holandesa e estimar as curvas de relação gordura:proteína em vacas categorizadas como acidose ruminal e cetose subclínica. Foram utilizados dados do serviço de controle leiteiro da Associação Paranaense de criadores de bovinos da raça Holandesa (APCBRH) referentes ao período entre 2010 e 2019. No capítulo I foram utilizados 11 modelos e ajustados separadamente à cada lactação (1ª, 2ª e 3ª lactação) pelo procedimento NLIN do programa SAS, depois comparados com base em diferentes medidas de qualidade de ajuste. Constatou-se que o melhor modelo segundo os critérios de ajuste foi o de Wood (1967), Rook (1993) e Wilmink (1987) para produção de leite, enquanto para as características de sólidos os melhores modelos foram o Rook (1993) e Dijkstra (1997). De maneira geral, o modelo Papajcsik e Bodero (1988) proporcionou o pior ajuste para todas as características. No capítulo II as curvas de lactação foram estimadas pelo modelo Wood (1967) de acordo com ordem de lactação, região e estação de parto. E por meio do procedimento GLM do SAS, avaliou-se a influência dos fatores ambientais sobre os parâmetros da curva de lactação (produção inicial (PI), tempo ao pico (TP), produção no pico (PP) e persistência (PER)) e a produção de leite estimada (L305). Os resultados indicaram que o formato da curva de lactação é dependente dos fatores ambientais, mostrando que os fatores ambientais influenciaram significativamente nos parâmetros da curva de lactação. No capítulo III a primeira parte os parâmetros genéticos para as características das curvas de lactação (PI, TP, PP e PER) e produção de leite estimada (L305) foram estimados em análises unicaracterística e bicaracterística. As herdabilidades foram de baixa magnitude (0,05 a 0,10), exceto para a PP (0,33). As correlações genéticas entre as características da curva de lactação foram de moderada a alta magnitude, variando de -0,35 a 0,99, e estas com o L305 foram todas positivas e de moderada a alta magnitude (0,38 a 0,86). Na segunda parte para as seis medidas de persistência os parâmetros genéticos foram estimados com um modelo de regressão aleatória utilizando o software GIBBS2F90. De modo geral entre as características da curva de lactação sugere que a PP como critério de seleção, e entre as medidas de persistências, a PS3 e PS4 são ideais para análise de persistência. No capítulo IV os parâmetros genéticos foram estimados com um modelo de regressão aleatória, utilizado o software Gibbs2f90. A herdabilidade para as PLDC foram de baixa a moderada magnitude (0,16 a 0,23), enquanto que para as características de fertilidade foram de baixa magnitude (0,04 a 0,07). A correlação genética entre a PLDC e as características de fertilidades foram positivas. Em geral, os resultados indicam que as PLDC são herdáveis e podem ser usadas como critério de seleção, enquanto que para as características de fertilidade, o melhoramento genético pode ser demorado e lento através da seleção direta. Além disso, a seleção para o aumento da produção de leite pode prolongar os dias do parto até a primeira inseminação, dias do parto até a inseminação com sucesso e intervalo de partos. No capítulo V os distúrbios metabólicos (acidose ruminal e cetose subclínica) foram avaliados com base na RGP e os parâmetros genéticos foram estimados com um modelo de regressão aleatória. Em geral, os resultados mostraram que 17,81%, das vacas estavam com algum nível de acidose ruminal (RGP < 1,0) e 8,42% com cetose subclínica (RGP 1,5), mas a maior parte permaneceu dentro da faixa ideal. A herdabilidade para RGP variou entre 0,17 e 0,27, e a correlação genética com a PLDC foi negativa ao longo da lactação, enquanto que as correlações genéticas com as características de fertilidades foram positivas no início da lactação e negativas no final da lactação (exceto com a PP1C). Além disso, os resultados indicaram que a RGP é uma característica herdável, animais geneticamente com menor RGP no terço inicial e final da lactação é desejável para a PLDC, por outro lado é indesejável para as características de fertilidade.

The thesis aim was: (I) determine appropriate models that explain the lactation curve and percentages of solids in the first three lactations of Holstein cows, (II) to evaluate how the effects of region, calving season and lactation order interact in order to alter the lactation curve in Holstein cows, (III) to estimate the genetic parameters for the traits of lactation curve and evaluation of persistence of lactation using random regression models in Holstein cows, (IV) to estimate the genetic association between milk production and fertility traits in primiparous Holstein cows and (V) to estimate the genetic association between the fat:protein ratio, and milk production and fertility in Holstein cows, and estimate the fat:protein ratio curves in cows categorized as ruminal acidosis and subclinical ketosis. Data from the dairy control service of the Paraná Holstein Breeders Association (APCBRH) from 2010 to 2019 were used. In Chapter I, 11 models were used and adjusted for each lactation (1st, 2nd and 3rd lactation) by the NLIN procedure of the SAS program, then compared based on different measures of fit quality. It was found that the best model according to the adjustment criteria was that of Wood (1967), Rook (1993) and Wilmink (1987) milk production, while for the traits of solids the best models were Rook (1993) and Dijkstra (1997). In general, the Papajcsik and Bodero (1988) model provided the worst fit for all traits. In chapter II, the lactation curves were estimated by the Wood model (1967) according to the lactation order, region and calving season. And through the SAS GLM procedure, the influence of environmental factors on the parameters of the lactation curve (initial milk production (PI), time in days to reach the peak of lactation (TP), Production at the peak of lactation (PP) and persistence (PER)) was evaluated and the estimated milk production (L305).The results indicated that the shape of the lactation curve is dependent on environmental factors, showing that environmental factors significantly influenced all parameters of the lactation curve. In Chapter III the first part, the genetic parameters for the traits of the lactation curves (PI, TP, PP and PER) and estimated milk production (L305) were estimated in univariate and bivariate analyzes. Heritabilities were of low magnitude (0.05 to 0.10), except for PP (0.33). The genetic correlations between the traits of the lactation curve were moderate to high magnitude, ranging from -0.35 to 0.99, and these with L305 were all positive and from moderate to high magnitude (0.38 to 0.86). In the second part for the six persistence measures, the genetic parameters were estimated with a random regression model using the GIBBS2F90 software. In general, among the traits of the lactation curve, it suggests that PP as a selection criterion, and among persistence measures, PS3 and PS4 are ideal for persistence analysis. In chapter IV the genetic parameters were estimated with a random regression model, using the Gibbs2f90 software. Heritability for PLDCs was low to moderate magnitude (0.16 to 0.23), while for fertility traits they were low (0.04 to 0.07). The genetic correlation between PLDC and fertility traits was positive. In general, the results indicate that PLDC are inheritable and can be used as a selection criterion, whereas for fertility traits, genetic improvement can be slow and slow through direct selection. In addition, selection for increased milk production can extend calving days until the first insemination, calving days until successful insemination and the calving interval. In chapter V metabolic disorders (ruminal acidosis and subclinical ketosis) were assessed based on RGP and genetic parameters were estimated using a random regression model. In general, the results showed that 17.81% of the cows had some level of ruminal acidosis (RGP <1.0) and 8.42% with subclinical ketosis (RGP 1.5), but most of them remained within the ideal range. Heritability for RGP ranged between 0.17 and 0.27, and the genetic correlation between RGP and PLDC was negative during lactation, while the genetic correlations between RGP and fertility traits were positive at the early of lactation and negative at the end of lactation (except with PP1C). In addition, the results indicated that RGP is an inheritable trait, animals genetically with lower RGP in the initial and final third of lactation are desirable for PLDC, on the other hand it is undesirable for fertility characteristics.

FATORES DE PATOGENICIDADE DE Staphylococcus spp. EM LEITE DE VACAS COM TRATAMENTO NÃO CONVENCIONAL DA MASTITE

Objetivou-se caracterizar e comparar a formação de biofilme, suscetibilidade a antimicrobianos in vitro, presença e distribuição de genes de virulência e de resistência antimicrobiana, além de determinar a diversidade clonal de estirpes de Staphylococcus spp. isoladas em leite de vacas tratadas e não tratadas com homeopatia. Os isolados de Staphylococcus spp. foram identificados por reação em cadeia da polimerase-espaço transcrito interno (ITS-PCR) e foram investigados quanto a presença dos genes sea, seb, sec, sed, see, tsst-1, pvl e eta codificadores de toxinas, dos genes icaABCD, bap, aap, atlE e bhp relacionados com a produção de biofilme e dos genes blaZ e mecA associados com a resistência antimicrobiana. Amostras mecA positivas foram tipadas para o tipo SCCmec por Multiplex Polymerase Chain Reaction (PCR Multiplex), enquanto a pesquisa de produção in vitro de bioflme ocorreu pelo método de aderência em placas de poliestireno. O perfil de resistência antimicrobiana foi determinado pelo método de disco-difusão em ágar e o perfil de restrição enzimática por Pulsed-Field Gel Electroforesis (PFGE). Clusters de S. aureus e S. epidermidis com três ou mais isolados tiveram uma linhagem selecionada para tipagem por Multilocus Sequence Typing (MLST), cujas sequências foram analisadas por banco de dados (http://www.mlst.net). Verificou-se prevalência de S. aureus (50,5%), que apresentou distribuição semelhante nos dois grupos, enquanto Staphylococcus spp. coagulase-negativos (CoNS) (70,8%) foram frequentes em vacas tratadas (p=0,036). O gene sec ocorreu apenas em S. chromogenes, com maior frequência em animais tratados (p=0,004) e o gene pvl foi encontrado em 66,7% de S. aureus. O operon icaADBC e os genes icaA e icaD associados prevaleceram em S. aureus, porém o gene icaD foi predominante no grupo de vacas tratadas (p=0,012). Os genes atlE e aap foram carreados apenas por S. epidermidis. Entre as estirpes com produção de biofilme in vitro, 76,8% continham pelo menos um gene relacionado com esta característica. Os genes mecA e Blaz apresentaram distribuição similar em vacas tratadas e não tratadas, porém mecA foi identificado apenas em S. epidermidis (12,1%), todos tipados como SCCmec tipo I. A susceptibilidade antimicrobiana revelou um perfil de multirresistência em 29,3% das estirpes. Houve predominância de um cluster majoritário em S. epidermidis e S. chromogenes, o que não ocorreu para S. aureus. A sequência do tipo (ST) 81 foi predominante em S. epidermidis, enquanto as STs 1, 5 e 126 em S. aureus. A presença de genes de toxinas, resistência antimicrobiana e biofilme, bem como a produção in vitro deste fator de patogenicidade, aliados à persistência de perfis clonais bacterianos, demonstram que sistemas em transição para manejos orgânicos podem representar risco à saúde pública pela circulação de patógenos zoonóticos em leite bovino. Medidas eficazes devem ser tomadas no controle dos produtos lácteos e manejo dos animais.

The present study aimed to characterize and compare biofilm formation, in vitro antimicrobial susceptibility, and the presence and distribution of virulence and antimicrobial resistance genes, as well as to determine the clonal diversity of Staphylococcus spp. strains isolated in milk from cows treated or not with homeopathy. The Staphylococcus spp. isolates were identified by polymerase chain reaction targeting the internal transcribed spacer (ITS-PCR) and were investigated regarding the presence of the sea, seb, sec, sed, see, tsst-1, pvl, and eta toxin-encoding genes, the icaABCD, bap, aap, atlE, and bhp genes, related to the production of biofilm, and the blaZ and mecA genes, which are associated with antimicrobial resistance. mecA-positive samples were typed for SCCmec by Multiplex Polymerase Chain Reaction (Multiplex PCR), while the assessment of in vitro biofilm production was carried out using the polystyrene plate adhesion method. The antimicrobial resistance profile was determined using the agar disc diffusion method, and the enzyme restriction profile, by Pulsed-Field Gel Electrophoresis (PFGE). Clusters of S. aureus and S. epidermidis with three or more isolates had one strain selected for typing by Multilocus Sequence Typing (MLST), and the sequences were analyzed on an online database (http://www.mlst.net). A 50.5% prevalence of S. aureus was observed, with similar distribution in both groups, while coagulase-negative Staphylococcus spp. (CoNS) were frequent (70.8%) in treated cows (p=0.036). The sec gene was found only in S. chromogenes and more frequently in treated animals (p=0.004), while the pvl gene was observed in 66.7% of the S. aureus. The icaADBC operon and the associated icaA and icaD genes prevailed in S. aureus, although the icaD gene was predominant in the treated cows group (p=0.012). The atlE and aap genes were carried only by S. epidermidis. Among the strains presenting in vitro biofilm production, 76.8% had at least one gene related to this trait. The mecA and Blaz genes exhibited similar distribution in treated and untreated cows, although mecA was identified only in S. epidermidis (12.1%), all of which were typed as SCCmec type I. The antimicrobial susceptibility assay revealed a multiresistance profile in 29.3% of the strains. There was a predominance of a major cluster in S. epidermidis and S. chromogenes, which did not occur for S. aureus. Sequence type (ST) 81 was predominant in S. epidermidis, while STs 1, 5, and 126 were prevalent in S. aureus. The presence of genes related to toxin production, antimicrobial resistance, and biofilm formation, as well as the in vitro production of this pathogenicity factor, combined with the persistence of bacterial clonal profiles, demonstrate that systems in transition to organic management can represent a risk to public health due to the circulation of zoonotic pathogens in bovine milk. Effective measures must be taken to control dairy products and animal management.

Efeito de diferentes intensidades de pastejo no estabelecimento do azevém anual (Lolium multiflorum Lam.) após sobressemeadura ou ressemeadura natural em sistema integrado de produção agropecuária

O azevém anual é uma das forrageiras mais utilizadas em sistemas integrados de produção agropecuária (SIPA) em regiões de clima subtropical por todo o mundo por apresentar rápido estabelecimento e fornecer forragem de excelente qualidade para os animais, mantendo o sincronismo dos processos produtivos. A ressemeadura natural é uma importante estratégia de manejo que, quando bem administrada, pode garantir o reestabelecimento do pasto ano após ano. Avaliou-se a capacidade de estabelecimento do azevém anual por ressemeadura natural ou via ressemeadura natural mais sobressemeadura mecânica (ressemeadura natural + 30 kg de semente ha-¹) em um protocolo experimental de longa duração, iniciado em 2001, de integração soja-bovinos de corte. Diferentes intensidades de pastejo, representadas por alturas de manejo de 10 cm (intensidade alta), 20 cm (intensidade moderada), 30 cm (intensidade moderada-leve), 40 cm (intensidade leve) e uma área sem pastejo, foram utilizadas para representar parcelas principais e comparar dois métodos de estabelecimento do pasto, com e sem sobressemeadura, que constituíram as subparcelas. O experimento foi delineado em blocos ao acaso com parcelas subdivididas, com 3 repetições de área. Durante o período de estabelecimento do pasto, foi determinada a altura média das plantas que, posteriormente foram quantificadas e pesadas para determinação da massa expressa em matéria seca. A liteira presente nas unidades amostrais, também foi avaliada. O número de plantas foi significativamente inferior em intensidades altas de pastejo e onde não houve sobressemeadura. Nas demais intensidades, essa variável não acusou diferença. A altura do dossel e a massa de plantas demonstraram inferioridade somente nas intensidades altas de pastejo. A massa da liteira não diferiu entre intensidades altas e moderadas, sendo superior apenas nas intensidades leves e áreas não pastejadas. A sobressemeadura restaurou a população do azevém nas intensidades altas de pastejo. Nas demais áreas de avaliação, não houve incremento no número de plantas e na capacidade de estabelecimento do pasto por acréscimo de sementes. Intensidades altas de pastejo inviabilizaram o estabelecimento satisfatório do azevém anual, evidenciando um processo de degradação na persistência do pasto manejado por ressemeadura natural. No entanto, intensidades moderadas e leves de pastejo não afetaram a persistência e o estabelecimento inicial dos pastos, após um ano de ressemeadura natural. A sobressemeadura anual é fundamental para recuperar a capacidade produtiva de pastos de azevém mantidos sob regime de intensidades altas de pastejo.

Italian ryegrass is one of the most widely used forage in integrated crop-livestock system (ICLS) in subtropical regions around the world because it has a fast establishment and provides excellent quality forage for animals, maintaining the synchronism of production processes. Self-seeding is an important management strategy that, when well managed, can guarantee the reestablishment of pasture year after year. The ability to establish Italian ryegrass was evaluated by self - seeding or self - seeding plus mechanical overseeding (self - seeding + 30 kg of seed ha-1) in a long-term experimental protocol (started in 2001) of soybean-beef cattle integration. Different grazing intensities, represented by sward management heights of 10 (high intensity), 20 (moderate intensity), 30 (moderate-light intensity) and 40 cm (light intensity) and an ungrazed area were used to represent main plots and compare two methods of pasture establishing, with and without overseeding, which constituted the subplots. The experiment was designed in random blocks with subdivided plots, with 3 replications of area. During the pasture establishment period, the average height of the plants was determined, which were later quantified and weighed to determine the mass expressed in dry matter. The soil litter, present in the sample units, was also evaluated. The number of plants was significantly lower at high grazing intensities, as well as in areas whith no overseeding. In the other intensities, this variable showed no difference. The canopy height and the plant mass showed inferiority only at high grazing intensities. The litter mass did not differ between high and moderate intensities, being higher only in light intensities and ungrazed areas. Overseeding restored the ryegrass population at high grazing intensities. In the other areas of evaluation, there was no increase in the number of plants and in the capacity to establish the pasture by adding seeds. High grazing intensities prevented the satisfactory establishment of annual ryegrass, showing a degradation process in the persistence of pasture managed by self - seeding. However, moderate and light grazing intensities did not affect the persistence and initial establishment of pastures, after one year of self-seeding. Annual overseeding is essential to recover the productive capacity of ryegrass pastures maintained under high grazing intensities.

Dinâmica da formação de biofilmes puros e mistos de Listeria monocytogenes e Salmonella Typhimurium em superfície de polipropileno

Biofilmes multiespécies são ecossistemas microbianos complexos que podem ser fonte de contaminação entre ambientes industriais e alimentos. O estudo, teve como objetivos realizar a caracterização molecular e avaliar expressão de genes relacionados à formação de biofilme, bem como, a dinâmica de formação e arquitetura de biofilmes puros e mistos de Listeria monocytogenes e Salmonella Typhimurium. Os três isolados de L. monocytogenes foram submetidos a caracterização de genes relacionados a formação de biofilme (flaA, prfA, luxS, agrA, agrB, agrC, agrD), a resistência a biocidas (mdrT, mdrM, mdrL, idE), a adaptação ao pH e a concentrações de sal (SSI-1 lmo 0444, SSI-1 lmo 0445, SSI-1 lmo 0446). Um isolado de S. Typhimurium foi submetido a avaliação de genes envolvidos na produção de fímbrias, adesão, virulência, formação de celulose e biofilme (adrA, lpfA, agfA, sipA), a quorum sensing (sidA) e a resistência ao amônio quaternário (qacE1). A dinâmica de formação de biofilmes puros e mistos foi avaliada nos tempos de 1 h, 24 h, 96 h e 120 h em superfície de polipropileno a 12 °C e 37 °C. Os biofilmes maduros de L. monocytogenes na condição pura e associada com S. Typhimurium em superfície de polipropileno a 12 °C e 37 °C foram submetidos a expressão dos genes flaA, prfA, luxS e agrABCD. Os isolados de L. monocytogenes apresentaram os genes flaA, prfA, luxS, agrA, agrB, agrC, agrD, mdrT, mdrM, mdrL e idE, e S. Typhimurium carreava os genes adrA, lpfA, agfA, sipA, sidA. O crescimento planctônico e séssil de L. monocytogenes e S. Typhimurium foi relacionado a temperatura de incubação, obtendo-se contagens mais elevadas em 24 h a 37 °C, e em 96 h e 120 h a 12 °C. A adesão inicial de L. monocytogenes e S. Typhimurium foi afetada negativamente pela condição mista (p<0,001). Biofilmes puros de L. monocytogenes e S. Typhimurium apresentaram contagens mais elevadas em 96 h e 120 h quando comparados as populações individuais em biofilmes mistos. Contudo, não foi observado diferença estatística na contagem entre biofilmes puros de L. monocytogenes, puros de S. Typhimurium e a população total em biofilmes mistos (Listeria+Salmonella) a 12 °C. Em MEV, pode-se observar estrutura de aspecto viscoso promovendo a adesão (1 h) bacteriana em biofilmes mistos, e a partir de 24 h a presença de matriz exopolissacarídeos (EPS). Biofilmes puros e mistos foram capazes de manter células viáveis por 3000 h a 10 °C com contagens superiores a 120 h (p<0,05). Biofilmes maduros de L. monocytogenes não sofreram interferência da temperatura, superfície e condição mista com S. Typhimurium sobre a expressão dos genes prfA, luxS e agrBCD, contudo houve interferência na expressão de flaA e agrA. Desse modo, a caracterização da dinâmica de formação de biofilmes mistos, juntamente com presença e expressão de genes relacionados a formação de biofilme, demostrou a associação desses patógenos para a formação e manutenção de biofilmes mistos, e além disso, torna-se resultados importantes para a indústrias de alimentos e saúde pública.

Multispecies biofilms are complex microbial ecosystems that can be a source of contamination between industrial environments and food. The study aimed to evaluate the molecular characterization and expression of genes related to biofilm formation and stressful conditions, and the dynamics of formation and architecture of pure and mixed biofilms of L. monocytogenes and S. Typhimurium. L. monocytogenes isolates were subjected to the characterization of genes related to biofilm formation (flaA, prfA, luxS), to stressful conditions (agrA, agrB, agrC, agrD), biocide resistance (mdrT, mdrM, mdrL, idE), adaptation to pH and salt concentrations (SSI-1 lmo 0444, SSI-1 lmo 0445, SSI-1 lmo 0446, LMOf2365_0481). S. Typhimurium was evaluated for genes linked to fimbriae production, adhesion, virulence, cellulose and biofilm formation (adrA, lpfA, agfA, sipA), quorum sensing (sidA) and resistance to quaternary ammonium (qacE1). The formation of pure and mixed biofilms was evaluated at 1h, 24h, 96h and 120h on the polypropylene surface at 12°C and 37°C. The mature biofilms of L. monocytogenes were subjected to the gene expression the flaA, prfA, luxS, and agrABCD. The isolates of L. monocytogenes presented the genes flaA, prfA, luxS, agrA, agrB, agrC, agrD, mdrT, mdrM, mdrL and idE, and S. Typhimurium demonstrated the genes adrA, lpfA, agfA, sipA, sidA. Planktonic and sessile growth was directly related to incubation temperature, obtaining higher counts in 24h at 37°C, and in 96h at 12°C. The initial adhesion of L. monocytogenes and S. Typhimurium was affected by the mixed condition (p<0.001). Pure biofilms from L. monocytogenes and S. Typhimurium showed higher counts in 96h and 120h when compared to individual populations in mixed biofilms. However, no statistical difference was observed between pure biofilms of L. monocytogenes, pure S. Typhimurium and the total population in mixed biofilms (Listeria+Salmonella), especially at 120h/12°C. It was observed that the dispersion of adhered cells directly affected the maintenance of planktonic cells, especially after 96h in both temperatures. In SEM, structure of the viscous aspect could be observed promoting bacterial adhesion (1h) in mixed biofilms, and after 24h with the presence of matrix exopolysaccharides (EPS). The pure and mixed biofilms were able to maintain viable cells for 3000h at 10°C with counts greater in 120h (p<0.05). Mature biofilms of L. monocytogenes were not affected by temperature, surface, and association with S. Typhimurium on the expression of prfA, luxS and agrBCD genes, interfering with the expression of flaA and agrA. Thus, the dynamics of the formation of mixed biofilms, linked to the presence and expression of genes related to the formation biofilms, are factors that prove the association of these pathogens for the formation and maintenance of mixed biofilms, it becomes important results for the food industries and the public health.

Pesquisa de Staphylococcus coagulase negativa em utensílios e queijos mussarela fatiados comercializados em Garanhuns-PE e sua capacidade de formar biofilme

Staphylococcus coagulase negativa (SCN) são bactérias encontradas em produtos de origem animal como contaminantes, capazes de produzir biofilmes e também enterotoxinas. O objetivo deste estudo foi investigar a presença dos genes de enterotoxinas sea, seb, sec e sed e a capacidade de formar biofilmes por isolados de Staphylococcus coagulase negativa em queijos Mussarela fatiados e fatiador de frios provenientes de panificadoras, mercados e minimercados da cidade de Garanhuns-PE. De um total de 85 isolados de SCN foram identificadas nove espécies bacterianas, sendo as mais frequentes: Staphylococcus (S.) saprophyticus 22 (25,9%), S. xylosus 14 (16,5%) e S. cohnii subsp. urealyticum 7 (8,2%). Não houve diferença significativa entre as espécies encontradas nas amostras de queijo Mussarela e nas superfícies dos fatiadores de frios. Desse total, 41 (48,2%) foram produtores de biofilme e 44 (51,8%) não produziram biofilme, com a maior frequência de detecção nas espécies S. saprophyticus e S. cohnii subsp. urealyticum. Os produtores de biofilme foram ainda, classificados como fraco produtores (61,0%), moderado produtores (22,0%) e forte produtores (17,0%). Quanto à presença de genes sea, seb, sec e sed, codificadores para enterotoxinas SEA, SEB, SEC e SED, respectivamente, em nenhum isolado foi detectada a presença destes genes. Mesmo com a ausência dos genes codificadores para enterotoxinas pesquisados nos isolados de SCN, estas espécies constituem importante fonte epidemiológica, pois além de apresentarem altas contagens nas amostras, o que indica uma má qualidade microbiológica, uma vez que são indicadores de contaminação, foram capazes de produzir biofilmes. Além disso, diferentes autores têm documentado a presença de genes para enterotoxinas nesse grupo de microrganismos. Assim pode-se concluir que os queijos Mussarela e os fatiadores de frios alvos deste estudo, estavam contaminados com SCN produtores de biofilme e que não possuem a presença dos genes de enterotoxinas clássicas estudadas. Entretanto ressalta-se a necessidade da aplicação de boas práticas de manipulação e higienização, uma vez que esse grupo bacteriano é um importante indicador da qualidade dos alimentos.

Coagulase-negative Staphylococci (CNS) are bacteria found in animal products as contaminants, and also capable of producing biofilms. The objective of this study was to identify CNS species in sliced mozzarella cheeses and cold-cut slicers from bakeries, markets and mini-markets of the city of Garanhuns-PE. Moreover, investigate the ability to form biofilms and the presence of enterotoxin genes sea, seb, sec and sed in the isolated bacteria. Nine bacterial species were identified from a total of 85 CNS isolates, with the most frequent being Staphylococcus (S.) saprophyticus 22 (25.9%), S. xylosus 14 (16.5%) and S. cohnii subsp. urealyticum 7 (8,2%). There was no significant difference between the species found in the samples of Mozzarella cheese and on the surfaces of cold-cut slicers. Of these, 41 (48.2%) were biofilm producers and 44 (51.8%) did not produce biofilms, with the highest detection frequency in S. saprophyticus and S. cohnii subsp. urealyticum. The biofilm producers were also classified as weak producers (61.0%), moderate producers (22.0%) and strong producers (17.0%). Regarding of sea, seb, sec and sed genes, enterotoxin encoders of SEA, SEB, SEC and SED respectively, the presence of these genes was not detected in the isolates. Even with the absence of enterotoxin encoding genes in CNS isolates, these species constitute an important epidemiological source, as they had high counts in the samples, indicating a poor microbiological quality, once they are considered indicators of contamination, it were able to produce biofilms. In addition, several authors have documented the presence of enterotoxin genes in this group of microorganisms. Thus, it can be concluded that the Mozzarella cheeses and the cold-cut slicers of this study were contaminated with CNS producing biofilms and did not carry the classical enterotoxin genes studied. However, the needed to apply good handling and hygiene practices is emphasized, since this bacterial group is an important indicator of the food quality.

XXX- EFEITO DA ADUBAÇÃO NITROGENADA E DA CONSORCIAÇÃO COM LEGUMINOSAS NA PRODUÇÃO E PERSISTÊNCIA DE HÍBRIDOS INTERESPECÍFICOS DO GÊNERO Paspalum

O grupo Pliculula é um grupo taxonômico pertencente ao gênero Paspalum que contém espécies importantes considerando sua diversidade genotípica para as características da forragem, e algumas dessas espécies foram melhoradas através da hibridação interespecífica artificial. O nitrogênio (N) é um importante fator limitante para a produção de biomassa. As leguminosas forrageiras contribuem com a fixação simbiótica do N2 atmosférico e podem aumentar a produção de biomassa e o valor nutritivo das pastagens. Os objetivos desta dissertação foram: (i) avaliar a produção de massa seca total de híbridos interespecíficos do gênero Paspalum, submetidos a diferentes níveis de adubação nitrogenada, tolerância ao frio e persistência de plantas; (ii) comparar a produção de biomassa sob níveis de adubação nitrogenada e no consórcio de leguminosas. Em razão disso, (iii) selecionar os melhores híbridos para as próximas etapas dentro do programa de melhoramento genético de plantas forrageiras da UFRGS. O estudo foi conduzido no período de agosto de 2017 a janeiro de 2019. O delineamento experimental foi em blocos casualizados, em arranjo de parcelas subdivididas com três repetições. Os tratamentos foram cinco doses de N (0, 60, 120, 240 e 480 kg N ha-1 N) e um consórcio com leguminosas (Trifolium repens + Lotus corniculatus) como parcela principal, e seis genótipos (1020133, 102069, 103084 , 103061, P. guenoarum ecótipo Azulão e Megathyrsus maximus cv. Aruana utilizados como controle) como subparcelas. As taxas de nitrogênio de 240 e 480 kg N ha-1 aumentaram a produção de MST, a tolerância ao frio e a persistência. A produção de MST no consórcio foi similar às doses de 120 kg.ha-1 de N. O híbrido 1020133 apresentou MST semelhante ao Azulão e foi superior ao cv. Aruana Portanto, existe a oportunidade de aumentar a MST, a tolerância ao frio e a persistência das plantas, além de melhorar o valor nutricional por meio da seleção de genótipos e do manejo de N. Além disso, o consórcio leguminosa pode apresentar melhor valor nutricional que o monocultivo de capim adubado com N, e pode ser uma prática alternativa para substituir a aplicação de adubação nitrogenada até a dose de 200 kg N ha-1. O híbrido 1020133 deve ser indicado para novos estudos, como produção de sementes e desempenho animal.

The Pliculula group is a taxonomic group belonging to the genus Paspalum that contains interesting species considering its genotypic diversity for forage characteristics, and some of these species were improved through artificial interspecific hybridization. Nitrogen (N) is an important limiting factor for producing biomass. Forage legumes contribute with symbiotic fixation of atmospheric N2 and may increase biomass production and nutritive value of pastures. The objectives of this dissertation were: (i) to evaluate the total dry mass production of interspecific hybrids of the genus Paspalum, submitted to different levels of nitrogen fertilization, cold tolerance and plant persistence; (ii) to compare biomass production under nitrogen fertilization levels and in the legume consortium. Because of this, (iii) select the best hybrids for the next steps within the program of genetic improvement of forage plants of UFRGS. The study was conducted in the period from August 2017 to January 2019. The experimental design was in randomized blocks, in arrangement of subdivided plots with three replicates. The treatments were five doses of N (0, 60, 120, 240 and 480 kg N ha-1 N), and a consortium with legumes (Trifolium repens + Lotus corniculatus) as main plot, and six genotypes (1020133, 102069, 103084, 103061, P. guenoarum ecotype Azulão and Megathyrsus maximus cv. Aruana used as control) as subplots. Nitrogen rates of 240 and 480 kg N ha-1 increased MST production, cold tolerance and persistence. Production of MST for the consortium was similar to the doses of 120 kg.ha-1 of N. The 1020133 hybrid had MST similar to Azulão and was superior to cv. Aruana. Therefore, there is an opportunity to increase MST, cold tolerance and plant persistence, as well as improve nutritional value through genotype selection and N management. In addition, the grass-legume consortium may present better value nutrient than the monoculture grass fertilized with N, and may be an alternative practice to replace the application of nitrogen fertilizer up to the dose of 200 kg N ha-1. The hybrid 1020133 should be indicated for new studies, such as seed production and animal performance.