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1.
Anim. Reprod. (Online) ; 20(2): e20230085, 2023. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1452316

Resumo

The establishment and maintenance of a pregnancy that goes to term is sine qua non for the long-term sustainability of dairy and beef cattle operations. The oocyte plays a critical role in providing the factors necessary for preimplantation embryonic development. Furthermore, the female, or maternal, environment where oocytes and embryos develop is crucial for the establishment and maintenance of a pregnancy to term. During folliculogenesis, the oocyte must sequentially acquire meiotic and developmental competence, which are the results of a series of molecular events preparing the highly specialized gamete to return to totipotency after fertilization. Given that folliculogenesis is a lengthy process in the cow, the occurrence of disease, metabolic imbalances, heat stress, or other adverse events can make it challenging to maintain oocyte quality. Following fertilization, the newly formed embryo must execute a tightly planned program that includes global DNA remodeling, activation of the embryonic genome, and cell fate decisions to form a blastocyst within a few days and cell divisions. The increasing use of assisted reproductive technologies creates an additional layer of complexity to ensure the highest oocyte and embryo quality given that in vitro systems do not faithfully recreate the physiological maternal environment. In this review, we discuss cellular and molecular factors and events known to be crucial for proper oocyte development and maturation, as well as adverse events that may negatively affect the oocyte; and the importance of the uterine environment, including signaling proteins in the maternal-embryonic interactions that ensure proper embryo development. We also discuss the impact of assisted reproductive technologies in oocyte and embryo quality and developmental potential, and considerations when looking into the prospects for developing systems that allow for in vitro gametogenesis as a tool for assisted reproduction in cattle.(AU)


Assuntos
Animais , Feminino , Gravidez , Bovinos/embriologia , Colo do Útero/embriologia , Células Germinativas/citologia , Técnicas de Reprodução Assistida/veterinária , Desenvolvimento Embrionário
2.
Rev. bras. reprod. anim ; 47(2): 238-243, abr.-jun. 2023.
Artigo em Espanhol | VETINDEX | ID: biblio-1444326

Resumo

A sazonalidade reprodutiva e a condição nutricional são os principais fatores que influenciam o desempenho reprodutivo em ovinos, principalmente em áreas onde a disponibilidade de alimentos é altamente sazonal. A desnutrição pode comprometer a competência folículo-oocitária, a função lútea e o desenvolvimento embrionário. Por outro lado, o tratamento com melatonina é um método eficaz para induzir ciclicidade, aumentando a ovulação e melhorando a viabilidade do embrião durante o anestro. Portanto, levantamos a hipótese de que a melatonina pode substituir os efeitos prejudiciais da desnutrição para melhorar o desempenho reprodutivo em ovelhas. A este respeito, esta revisão enfoca os efeitos da interação entre melatonina e nutrição na viabilidade do embrião e resume a informação disponível sobre o efeito da melatonina exógena na viabilidade do embrião em ovelhas desnutridas.(AU)


Reproductive seasonality and nutritional condition are the main factors that influence reproductive performance in sheep, particularly in the areas where the availability of food is highly seasonal. Undernutrition can compromise follicle-oocyte competence, luteal function and embryo development. On the other hand, melatonin treatment is an effective method for inducing estrous cycles, increasing ovulation and improving embryo viability during anestrus. Therefore, we hypothesized that melatonin can override the detrimental effects of undernutrition to improve reproductive performance in ewes. In this regard, this review focuses on the effects of the interaction between melatonin and nutrition on embryo viability and summarizes the available information about the effect of exogenous melatonin on embryo viability in undernourished ewes.(au)


Assuntos
Animais , Feminino , Ovinos/fisiologia , Desenvolvimento Embrionário , Estações do Ano , Folículo Ovariano/fisiologia
3.
Acta sci. vet. (Impr.) ; 51: Pub. 1922, 2023. tab
Artigo em Inglês | VETINDEX | ID: biblio-1443987

Resumo

Background: Enzootic bovine leukosis (EBL) is a widespread infectious disease caused by the bovine leukemia virus (BLV), which results in immune system dysfunction. The resulting immunosuppression may lead to an increased prevalence of other diseases. Dairy cows infected have altered immune function associated with decreased milk production and shortened lifespan and decreased immune response to immunization. BLV infection, however, is often asymptomatic, so any connection between subclinical infection and common reproductive diseases remains unknown. This study aimed to describe the relationship between naturally occurring subclinical BLV and infectious reproductive diseases seroconversion in the field. Materials, Methods & Results: The diseases investigated included Bovine viral diarrhoea (BVD), Bovine alfaherpesvirus 1 (BoHV-1), Bovine gammaherpesvirus 4 (BoHV-4), Chlamydiosis, Leptospirosis, Brucellosis and Neosporosis in dairy cattle. Six hundred fifty-five sera samples from the northern and south-central regions of Uruguay, from asymptomatic female Holstein and Holstein crosses without a history of vaccination against reproductive diseases were processed using reference diagnostic methods (Seronautalization, ELISA, MAT, Rose Bengal Plate test). The seroprevalence of BLV was 20.0%. Seroprevalence of reproductive diseases BVD, BoHV-1 and BoHV-4 were 99.3%, 41.2% and 27.3% of the populations, respectively, and the total seroprevalence of Leptospirosis, bovine Neospora caninum and Chlamydiosis were 19.8%, 29.8% and 33.0% respectively. The results revealed positive associations between naturally contracted BLV and the presence of antibodies against BoHV-1 (P = 0.002), as well as between naturally contracted BLV and presence of antibodies against Leptospira spp. (P = 0.028). Discussion: BLV infection can impact innate and adaptive immune system cells and alter the proper functioning of uninfected cells. BLV infection may also induce changes in the complex balance of cytokine expression, cell proliferation, and programmed cell death in T- and B-lymphocytes, which is critical for immune competence and effective response to infectious challenges. The progression of BLV infection has a substantial effect on host defense mechanisms. Indeed, lowmagnitude serologic responses to a commercial foot-and-mouth disease vaccine and a J5 Escherichia coli vaccine have been observed. These results are supported by recent trial studies showing a reduced immune response to vaccination against BoHV-1 and Leptospira spp. in asymptomatic animals infected with BLV. These are 2 of the most prevalent infectious reproductive diseases in cattle worldwide, and our results provide evidence that a link between BLV and susceptibility to these diseases may exist. Although there is evidence of the co-occurrence of these diseases, it remains unknown whether there is a direct or indirect effect of BLV on infertility, embryonic loss, or abortion. Another possibility is that natural infection with these reproductive pathogens (BoHV-1, Leptospira, or others) promotes BLV expression, negatively affecting the farms where these pathogens are endemic. Considering the high seroprevalence of BLV in dairy herds in North and South America where the infection is endemic, it was explored BLV's role as an immunosuppressant by quantifying its co-occurrence with diseases that affect reproductive performance in breeding herds. Future work should clarify the role of BLV and the co-occurring pathogens in causing infertility or abortions.


Assuntos
Animais , Feminino , Bovinos , Leucose Enzoótica Bovina/complicações , Vírus da Leucemia Bovina , Doenças dos Genitais Femininos/veterinária , Rinotraqueíte Infecciosa Bovina , Leptospirose/veterinária , Infecções do Sistema Genital/veterinária
4.
Anim. Reprod. (Online) ; 19(2): e20210074, mai. 2022. tab
Artigo em Inglês | VETINDEX | ID: biblio-1370131

Resumo

This study aimed to determine the effect of presence of the corpus luteum (CL) and its influence on cumulus­oocyte complexes (COCs) obtained from the ipsilateral or contralateral ovary in bovine on the recovery and capacity of the oocytes to sustain mono-spermic fertilization, undergo preimplantation development, and develop to the blastocyst stage. Ovaries were collected at a local slaughterhouse and kept in pairs corresponding to the same animal. In the first experiment the variables evaluated were compared between cows with (CCL+) and without (CCL- ) CL, and for the second experiment, comparisons were made between ovaries with an ipsilateral (CL+), contralateral (CL−), and no (NCL). The recovery rate of COCs was higher in ovaries from CCL− cows, and a higher proportion of grade 1 COCs were recovered from this group. A higher proportion of metaphase I oocytes at 7 h of maturation, and a higher rate of cleavage were observed in the CCL+ group; however, a higher proportion of embryos were obtained from the CCL− group. Besides, COCs from the CL+ group had a lower proportion of grades 1 and 2 morphological qualities, lower rate of metaphase II oocytes at 22 h of maturation, and lower rate of formation of two pronuclei, whereas a higher proportion of unfertilized oocytes after in vitro fertilization. On the other hand, the COCs from the CL− group displayed a lower proportion of oocytes with more than two pronuclei, higher cleavage rate, and higher final blastocyst production were obtained when compared to CL+. Thus, the effects of CL on the competence of bovine COCs are different depending on the anatomical proximity of their location in the animal, negatively affecting the quality of COCs located in the same ovary, but not having negative effects on the competence of COCs in the ovaries contralateral to their location.(AU)


Assuntos
Animais , Feminino , Bovinos , Oócitos , Fertilização in vitro , Corpo Lúteo , Estruturas Embrionárias
5.
Artigo em Português | VETINDEX | ID: biblio-1378431

Resumo

O Letramento Funcional em Saúde (LFS) é um dos determinantes sociais estabelecidos que indica a capacidade de se obter, analisar e aplicar as informações médicas, no entanto, ainda não existe um formulário aplicado à Medicina Veterinária. No presente trabalho, foi criado um teste de Letramento Funcional em Saúde Animal (LFSA) para ser avaliada a compreensão de tutores de cães e gatos a respeito de informações comumente utilizadas nas prescrições veterinárias. Apesar de entenderem as orientações verbais, 62% têm dificuldade para compreender os horários das medicações e termos técnicos (74%). Foi constatada a existência de associação entre o grau de LFSA e o nível de escolaridade e renda. Tutores com ensino fundamental e renda de até três salários-mínimos (58%) exibiram letramento de crítico (42%) a básico (61%), que foi associado à dificuldade de letramento (p<0,001 e p = 0,04). O teste apresenta questões rápidas e práticas e pode ser aplicado pelo médico-veterinário antes da prescrição e melhorar a comunicação com o tutor.(AU)


The Functional Health Literacy (FLH) is one of the social determinants that indicates the ability to obtain, analyze and apply medical information, however until now it was not applied in Veterinary Medicine. In the present paper it was created a Functional Literacy in Animal Health (FLAH) test to assess if dog and cat owner's can understand information commonly used in veterinary prescriptions. In spite of understanding the verbal guidelines, 62% have difficulty in understanding medication schedules and technical terms (74%). There was an association between the FLAH degree and the education level and income. The owners with complete primary education show critical (42%) and basic (61%) literacy along with an income of up to three minimum wages (58%), which are associated with literacy difficulties (p <0,001 and p = 0,04). The test presents quick and practical questions and can be applied by the veterinarian before the prescription, improving the communication with pet owners.(AU)


Assuntos
Compreensão , Avaliação Educacional/estatística & dados numéricos , Letramento em Saúde/métodos , Medicina Veterinária , Protocolo de Ensaio Clínico
6.
Anim. Reprod. (Online) ; 19(1): e20220009, 2022. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1367902

Resumo

The assessment of morphology and digital image opacity may provide valuable information on the present embryo quality. Time-lapse imaging has been employed in research to establish a means of monitoring the dynamic nature of preimplantation embryo development. The aim of present study was to use time-lapse imaging for assessing various prospective morphometric and phototextural markers of the developmental potential of in vitro-derived ovine embryos. Oocytes were obtained by scarification of ovaries from nine Polish Longwool ewes. After in vitro maturation (IVM) and fertilization (IVF) of oocytes with fresh ram semen, the development of embryos to the blastocyst stage was monitored and evaluated using Primo Vision time-lapse imaging technology. Commercially available Image-Pro® Plus software was used to measure zona pellucida thickness, embryo diameter, total area of the perivitelline space, cellular grey-scale pixel intensity and cellular pixel heterogeneity. Statistical assessment of all attributes was done at various time points during embryo development (i.e., presumptive zygote stage: t(0); first cleavage detected at t(2) or t(3); and second cleavage detected at t(4) or t(6)). Out of thirty-seven zygotes analyzed in this study, five did not divide, 26 arrested before and six developed to the blastocyst stage. Our present results indicate that most parameters analyzed did not differ among embryos varying in their developmental fate except for the perivitelline space area that was greater (P<0.05) for non-dividing zygotes than future blastocysts at the presumptive zygote stage (4040±1850 vs. 857±262 µm2, respectively; means±SEM). Consequently, the measurement of perivitelline space at t(0) can potentially be used to prognosticate developmental potential of in vitro-produced ovine embryos albeit further confirmational studies are needed.(AU)


Assuntos
Animais , Feminino , Oócitos , Técnicas In Vitro , Ovinos/embriologia , Desenvolvimento Embrionário , Fertilização , Imagem com Lapso de Tempo
7.
Anim. Reprod. (Online) ; 19(3): e20220035, set. 2022. ilus, graf, tab
Artigo em Inglês | VETINDEX | ID: biblio-1393230

Resumo

The purpose of this study is to investigate the role of some oxidative stress (OS), ceruloplasmin (Cp), and neopterin (NPT) as diagnostic biomarkers for dromedary camels endometritis as well as to explore the impact of ceftiofur treatment on endometritis. Camels were categorized into two groups; healthy control group (n = 20) and endometritis group (n = 60). She-camels with clinical signs of endometritis (CE) received 6.6 mg/kg BW of ceftiofur (i/m). On days 7, and 14, she-camels were evaluated and clinical cure or failure to cure was determined. The comparison of the groups for OS demonstrated that endometritis caused an increase in serum malondialdehyde (sMDA), Cp, and NPT levels (P<0.05), but decreased serum levels of superoxide dismutase (SOD), catalase (CAT), and glutathione (GSH) (P<0.05). The most prevalent pathogens involved in the etiology of CE are Arcanobacterium pyogenes, Streptococcus pyogenes, and Staphylococcus aureus. All examined biomarkers demonstrated a high degree of recognition between CE camel and healthy controls (the area under the curve (AUC) was 95.9 for NPT). A higher proportion of camels with CE that were treated with ceftiofur (90%, P<0.0001) showed clinical cure by the first dose, while 10% required a second dose. In conclusion, CE causes increased oxidative reactions and decreased antioxidant defense competence. Subsequently, the alteration in that balance that was represented by the biomarkers of OS could be beneficial for clinical practice and basic clinical research. Additionally, all trials demonstrated the efficacy of ceftiofur for the treatment of CE in she-camel.(AU)


Assuntos
Animais , Camelus/fisiologia , Biomarcadores/análise , Estresse Oxidativo/fisiologia , Ceruloplasmina/efeitos adversos , Neopterina/efeitos adversos , Endometrite/veterinária
8.
Anim. Reprod. (Online) ; 19(4): e20220119, 2022. ilus
Artigo em Inglês | VETINDEX | ID: biblio-1414520

Resumo

Arsenic exposure is a global health concern. This toxic metalloid is ubiquitous in the environment and contaminates food and drinking water. Once ingested, it undergoes a complex metabolic process within the body, which contributes to its accumulation and reactivity. Arsenic toxicity stems from the induction of oxidative stress, inhibition of thiol-containing proteins, and mimicry of inorganic phosphates. Arsenic poisoning is associated with the development of reproductive disorders. In males, arsenic causes a reduction in testicular weight and alterations in steroidogenesis and spermatogenesis. Moreover, it reduces the number and quality of spermatozoa harvested from the cauda epididymis. The mitochondria are targets of arsenic toxicity because of the production of free radicals and their high content of cysteine-rich proteins and fatty acids. Mitochondrial dysfunction may contribute to reproductive disorders because this organelle is crucial for controlling testicular and epididymal events related to sperm production and maturation. All of these alterations mediated by arsenic exposure contribute to the failure of male reproductive competence by reducing gamete viability. This review describes the potential mechanisms of arsenic toxicity, its detrimental effects on male reproductive organs, and consequences on sperm fertility.(AU)


Assuntos
Humanos , Animais , Masculino , Intoxicação por Arsênico/diagnóstico , Fármacos para a Fertilidade Masculina/análise , Mitocôndrias/química , Estresse Oxidativo/fisiologia , Epididimo/química
9.
Ciênc. Anim. (Impr.) ; 31(1,supl.1): 49-52, 2021. tab
Artigo em Português | VETINDEX | ID: biblio-1368996

Resumo

The bitch is an experimental model of wild and even endangered canids. Therefore, the study of the factors that influence your fertility benefits scientific advances in both segments. Knowing that pyometra is one of the common uterine pathologies in bitches, this work aimed to evaluate the effects of pyometra on the morphology and competence of canine oocytes through the use of Azul Cresil Brilhante (ACB). For this purpose, 1197 canine oocytes that were divided into 2 groups classified as control (healthy) and treatment (pyometra). They were morphologically classified into grade 1 (G1), grade 2 (G2) and grade 3 (G3) and according to the ACB stain as ACB (+) and ACB (­) (not stained). Bitches in the healthy group had higher amounts of total oocytes (795) and better quality (495 oocytes G1) and competence (45 ± 9.8 ACB (+)). The use of ACB was useful to distinguish the competence of the studied oocytes and can be an auxiliary tool for choosing the best oocytes.


Assuntos
Animais , Feminino , Cães , Oócitos/classificação , Recuperação de Oócitos/veterinária , Piometra/complicações , Piometra/veterinária , Indicadores e Reagentes
10.
Acta cir. bras ; 36(5): e360508, 2021. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278108

Resumo

ABSTRACT Purpose To develop and validate a chest cavity simulator for teaching video-assited thoracic surgery (VATS). Methods The first phase of the study consisted of developing a chest cavity simulator. A quasi-experimental study was performed in the second phase, and 25 surgeons and residents participated in a three-stage pulmonary suture experiment. The videos were recorded and timed. Generalized linear regression models for repeated measures were used to analyze the outcome change over time. Results The chest cavity simulator consists of a console simulating the left hemithorax. Among the participants, 96% rated the design, visual aspect, positioning ergonomics, and triangulation of the portals as very good or excellent (face validity). There was a decrease in suturing time in step 1 from 435.7 ± 105 to 355.6 ± 76.8 seconds compared to step 3 (p = 0.001). The evaluation of the simulation effectiveness and performance (content validity) was rated as very good or excellent by 96% ofparticipants. The most experienced surgeon showed significant reduction in procedure time (p = 0.021) (construct validity). Conclusions The thoracic cavity simulator is realistic, showing content and construct validity, and can be used in VATS training. The simulation model allowed skill gain in the endoscopic suture.


Assuntos
Cirurgia Torácica , Treinamento por Simulação , Simulação por Computador , Brasil , Reprodutibilidade dos Testes , Competência Clínica , Endoscopia
11.
Rev. Inst. Adolfo Lutz ; 80: e37420, dez. 2021. tab, graf
Artigo em Inglês | LILACS, CONASS, Coleciona SUS (Brasil), SES-SP, VETINDEX, SESSP-ACVSES, SES SP - Instituto Adolfo Lutz, SES-SP, SESSP-IALACERVO | ID: biblio-1377927

Resumo

Reference materials (RM) are tools used in the comparability and traceability of measurements. They are widely used by laboratories for method validation and quality control of assay. Chile must evaluate theperformance of laboratories that analyzing metals in fishery products, despite RM have high prices and are scarce. For that reason, a RM in a hydrobiological product was developed. Reference values for arsenic and cadmium elements for a fishmeal were assigned. The measurement methods for characterization of the material were Inductively Coupled Plasma Mass Spectrometry, Atomic Absorption Spectrometry and Neutron Activation Analysis. Reference values with their expanded uncertainty (U) were established for arsenic 2.64 ± 0.42 mg/kg (U; k = 2) and for cadmium 0.86 ± 0.16 mg/kg (U; k = 2). Homogeneity and stability of the RM allowed its use in a proficiency test for eleven food control laboratories. Results for median were 2.114 mg/kg for arsenic, and 0.863 mg/kg for cadmium. The performance values of the participants were evaluated with a z score obtaining 60% satisfaction for arsenic and 73% for cadmium.The material demonstrated to be suitable for use in interlaboratory proficiency assay. (AU)


Materiales de referencia (MR) son herramientas utilizadas en la comparabilidad y trazabilidad entre mediciones. Laboratorios los utilizan ampliamente en validación de métodos y control de calidad. Chile debe evaluar el desempeño de los laboratorios que analizan metales en productos pesqueros, a pesar de los altos precios y escasez del MR. Por esa razón, se desarrolló un MR en producto hidrobiológico. Se asignaron valores de referencia para arsénico y cadmio en harina de pescado. Los métodos de medición para la caracterización del material fueron Espectrometría de Masas de Plasma Acoplado Inductivamente, Espectrometría de Absorción Atómica y Análisis de Activación de Neutrones. Se establecieron valores de referencia con su incertidumbre (U) para arsénico 2.64 ± 0.42 mg/kg (U; k = 2) y para cadmio 0.86 ± 0.16 mg/kg (U; k = 2). La homogeneidad y estabilidad del MR permitieron su uso en una prueba de aptitud para once laboratorios de control de alimentos. Las medianas fueron 2,114 mg/kg para arsénico y 0,863 mg/kg para cadmio. Se evaluaron los rendimientos de los participantes con un estadístico de puntaje z satisfactorio del 60% para el arsénico y 73% para el cadmio. El material demostró ser adecuado para uso en ensayo de aptitud de intercomparación. (AU)


Assuntos
Arsênio , Cádmio , Ensaio de Proficiência Laboratorial , Farinha de Peixe , Laboratórios
12.
Artigo em Português | VETINDEX | ID: biblio-1489099

Resumo

Para fins de licenciamento sanitário, a portaria do Centro de Vigilância Sanitária Estadual de São Paulo, CVS nº 01/2020, classifica a Atividade Veterinária (CNAE 7500-1/00) como de alto risco no caso em que o estabelecimento mantenha estoque de medicamentos de uso humano para utilização em animais atendidos no local. Nessa situação, exige-se a presença de profissional responsável técnico pelo funcionamento do estoque de medicamentos, denominando-o de dispensário. Quando nesse estoque estiver incluída a guarda e fornecimento de medicamentos controlados (entorpecentes e psicotrópicos) de uso humano, a Vigilância Sanitária Estadual interpreta e orienta as Vigilâncias Municipais, que de acordo com a Portaria SVS MS nº 344/1998 apenas o profissional farmacêutico está habilitado a responder pelo dispensário, não reconhecendo a competência do profissional médico-veterinário como responsável pela guarda desses medicamentos no estabelecimento veterinário. Esse tema não está nacionalmente regulamentado, daí a importância de demonstrar a competência legal do médico-veterinário sobre a guarda de medicamentos controlados de uso humano, necessários para fins terapêuticos, clínicos ou diagnósticos realizados no estabelecimento veterinário.


For health licensing in the state of São Paulo, Brazil, the Veterinary Activity (CNAE 7500-1/00) is classified as being of high risk when the establishment keeps stock of human medicines used in animals treated in the place. In this situation, the presence of a technician responsible for what they consider to be a dispensary is required and, the State Health Surveillance consider that only a pharmaceutical professional is qualified for the custody and supply of human controlled medicines, and do not recognize the competence of the veterinary professional as responsible for the safekeeping these drugs in the veterinary establishment. This issue is not legally pacified; hence the importance of demonstrating the legal competence of the veterinarian on the safekeeping of medicines for human use, that the presence of a pharmacist cannot be required for veterinary establishment, even when there is a stock of human controlled medicines for therapeutic, clinical, or diagnostic purposes performed there.


Assuntos
Centros de Vigilância Sanitária Estaduais , Controle de Medicamentos e Entorpecentes/legislação & jurisprudência , Hospitais Veterinários/legislação & jurisprudência , Hospitais Veterinários/normas , Medicamentos de Controle Especial , Psicotrópicos , Brasil , Responsabilidade Técnica
13.
Rev. bras. reprod. anim ; 45(4): 655-668, out.-dez. 2021. ilus
Artigo em Português | VETINDEX | ID: biblio-1492719

Resumo

A exposição de bovinos a temperaturas elevadas pode causar hipertermia e alterações fisiológicas denominadas de estresse térmico. Este fenômeno tem sido caracterizado em várias espécies, sendo exacerbado em vacas leiteiras de alta produção. Apesar de estas alterações serem observadas em diversos órgãos e tipos celulares, oócitos e embriões pré-implantacionais são mais susceptíveis ao estresse térmico, resultando em reduções na fertilidade das vacas lactantes durante os meses mais quentes do ano. Os oócitos bovinos expostos ao estresse térmico apresentam alterações celulares e moleculares que reduzem a competência oocitária sendo carreados ao embrião pré-implantacional. A maturação in vitro de oócitos bovinos em condições de temperatura elevada (choque térmico) recapitula as principais alterações observadas in vivo, permitindo investigar em mais detalhes a susceptibilidade e os mecanismos de sobrevivência. O entendimento dos processos mediados pelo estresse térmico na fisiologia do oócito permitirá o desenvolvimento de estratégias para mitigar os efeitos negativos mantendo a competência oocitária


The exposure of cattle to high environmental temperatures may lead to hyperthermia and physiological changes known as heat stress. This phenomenon has been characterized in several species, albeit is a more profound problem in high-yielding dairy cows. Although these alterations are observed in several organs and cell types, oocytes and preimplantation embryos are more susceptible to heat stress, resulting in reductions in the fertility of lactating cows during the hottest months of the year. Bovine oocytes exposed to heat stress undergo cellular and molecular changes reducing oocyte competence which is carried out to the preimplantation embryo. In vitro maturation of bovine oocytes under conditions of high temperature (heat shock) recapitulates the main changes observed in vivo, allowing us to investigate the susceptibilities and survival mechanisms. Understanding the processes mediated by heat stress in oocyte physiology will allow the development of strategies to mitigate the negative effects while maintaining oocyte competence.


Assuntos
Feminino , Animais , Bovinos , Bovinos/embriologia , Desenvolvimento Embrionário , Oogênese , Transtornos de Estresse por Calor , Febre
14.
Rev. bras. parasitol. vet ; 30(3): e005721, 2021. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1288700

Resumo

Abstract Two lineages of Rhipicephalus sanguineus are known in Brazil: the temperate or southern and the tropical or northern populations. The distribution patterns of both lineages of R. sanguineus have epidemiological implications that can affect vectorial competence concerning Ehrlichia canis, the agent of canine monocytic ehrlichiosis. Intending to identify the microbiomes of both lineages and compare microorganisms in R. sanguineus, we used the 16S rRNA (V4-V5 region) gene-based metataxonomic approach, through NGS sequencing on the MiSeq Illumina platform. We selected specimens of females from the environment and samples of primary embryonic cell cultures, from both lineages, and this was the first study to investigate the prokaryotic microbiome in tick cell cultures. The results showed that many bacterial taxa detected in the samples were typical members of the host environment. A significant diversity of microorganisms in R. sanguineus females and in embryonic cell cultures from both lineages was found, with emphasis on the presence of Coxiella in all samples, albeit in different proportions. The Coxiella species present in the two lineages of ticks may be different and may have co-evolved with them, thus driving different patterns of interactions between ticks and the pathogens that they can harbor or transmit to vertebrate hosts.


Resumo Duas linhagens de Rhipicephalus sanguineus são conhecidas no Brasil: populações da linhagem temperada ou do sul, e tropical ou do norte. Os padrões de distribuição de ambas as linhagens de R. sanguineus têm implicações epidemiológicas, podendo afetar a competência vetorial de Ehrlichia canis, o agente etiológico da erliquiose monocítica canina. Com a intenção de identificar os microbiomas de ambas as linhagens e comparar microrganismos de R. sanguineus, foi utilizada a metataxonomia, baseada no gene 16S rRNA (região V4-V5), por meio do sequenciamento de nova geração na plataforma MiSeq Illumina. Foram selecionadas amostras de fêmeas do ambiente e cultivo primário de células embrionárias, considerando-se as duas linhagens conhecidas do Brasil. Este é o primeiro estudo que investiga o microbioma procariótico de células de cultura de carrapato. Os resultados mostram que muitos grupos de bactérias detectadas nas amostras são membros típicos do ambiente do hospedeiro. Uma diversidade significativa de microrganismos em fêmeas e cultura de células embrionárias nas duas linhagens de R. sanguineus foi encontrada, com ênfase na presença de Coxiella em todas as amostras, ainda que em diferentes proporções. Possivelmente, as espécies de Coxiella presentes nas duas linhagens de carrapatos são diferentes e co-evoluíram com essas linhagens, conduzindo a diferentes padrões de interação entre carrapatos e patógenos que podem abrigar ou transmitir aos hospedeiros vertebrados.


Assuntos
Animais , Feminino , Cães , Rhipicephalus sanguineus , Doenças do Cão , Microbiota , Brasil , RNA Ribossômico 16S/genética , Técnicas de Cultura de Células/veterinária
15.
Rev. bras. reprod. anim ; 45(4): 160-167, out.-dez. 2021.
Artigo em Português | VETINDEX | ID: biblio-1492654

Resumo

O período de transição das vacas leiteiras é marcado por diversas alterações fisiológicas, metabólicas e endócrinas. Essas alterações aumentam a susceptibilidade das vacas às infecções no pósparto o que compromete bem-estar, resultando em menor desempenho produtivo e reprodutivo, levando ao aumento dos custos relacionados ao tratamento das infecções e ao descarte de leite. Dentre as doenças que acometem as vacas leiteiras no período pós-parto destacam-se as patologias relacionadas ao trato reprodutivo (retenção de placenta, metrite, endometrite clínica e subclínica) ou em outros órgãos (mastite, claudicação, problemas digestivos e respiratórios), e os distúrbios metabólicos (cetose, hipocalcemia e deslocamento de abomaso). Embora o impacto negativo das doenças no pós-parto sobre a eficiência reprodutiva de vacas leiteiras já tenha sido demonstrado por diversos estudos, os mecanismos pelos quais os processos infecciosos e inflamatórios interferem direta e/ou indiretamente no funcionamento do trato reprodutivo das vacas leiteiras ainda não foram totalmente elucidados. Sabe-se que as respostas inflamatória e imunológica frente à infecção podem influenciar processos reprodutivos como a dinâmica folicular ovariana, a esteroidogênese, a competência ovocitária, a fertilização, o desenvolvimento embrionário e a manutenção da gestação. Portanto, a ocorrência de doenças no pós-parto é um obstáculo a eficiência reprodutiva, principalmente devido à alta incidência dessas infecções nas vacas de leite. Podese concluir que a prevenção é a melhor estratégia para combater os efeitos negativos da ocorrência das doenças do pós-parto na eficiência reprodutiva, pois mesmo após a cura clínica dessas patologias a eficiência reprodutiva não é reestabelecida, e seus efeitos persistem por toda a lactação.


The transition period of dairy cows is marked by several physiological, metabolic and endocrine changes. These changes increase the susceptibility of cows to postpartum infections, which compromises welfare, resulting in lower productive and reproductive performance, leading to increased costs related to the treatment of infections and milk disposal. Among the diseases that affect dairy cows in the postpartum period are pathologies related to the reproductive tract (retention of placenta, metritis, clinical and subclinical endometritis) or to other organs (mastitis, claudication, digestive, and respiratory problems), and metabolic disorders (ketosis, hypocalcemia and abomasal displacement). Although the negative impact of postpartum diseases on dairy cows reproductive efficiency has already been demonstrated by several studies, the mechanisms by which infectious and inflammatory processes directly and/or indirectly interfere in the reproductive tract of dairy cows have not yet been fully elucidated. It is known that inflammatory and immunological responses to infection can influence reproductive processes such as ovarian follicular dynamics, steroidogenesis, oocyte competence, fertilization, embryonic development, and maintenance of pregnancy. Therefore, the occurrence of postpartum diseases is an obstacle to reproductive efficiency, mainly due to the high incidence of these infections in dairy cows. It can be concluded that prevention is the best strategy to combat the negative effects of the occurrence of postpartum diseases on reproductive efficiency, because even after the clinical cure of these pathologies reproductive efficiency is not reestablished, and its effects persist throughout lactation.


Assuntos
Feminino , Animais , Bovinos , Endometrite/veterinária , Período Pós-Parto , Placenta Retida , Eficiência Biológica Relativa
16.
R. bras. Parasitol. Vet. ; 30(3): e005721, 2021. tab, graf
Artigo em Inglês | VETINDEX | ID: vti-31483

Resumo

Two lineages of Rhipicephalus sanguineus are known in Brazil: the temperate or southern and the tropical or northern populations. The distribution patterns of both lineages of R. sanguineus have epidemiological implications that can affect vectorial competence concerning Ehrlichia canis, the agent of canine monocytic ehrlichiosis. Intending to identify the microbiomes of both lineages and compare microorganisms in R. sanguineus, we used the 16S rRNA (V4-V5 region) gene-based metataxonomic approach, through NGS sequencing on the MiSeq Illumina platform. We selected specimens of females from the environment and samples of primary embryonic cell cultures, from both lineages, and this was the first study to investigate the prokaryotic microbiome in tick cell cultures. The results showed that many bacterial taxa detected in the samples were typical members of the host environment. A significant diversity of microorganisms in R. sanguineus females and in embryonic cell cultures from both lineages was found, with emphasis on the presence of Coxiella in all samples, albeit in different proportions. The Coxiella species present in the two lineages of ticks may be different and may have co-evolved with them, thus driving different patterns of interactions between ticks and the pathogens that they can harbor or transmit to vertebrate hosts.(AU)


Duas linhagens de Rhipicephalus sanguineus são conhecidas no Brasil: populações da linhagem temperada ou do sul, e tropical ou do norte. Os padrões de distribuição de ambas as linhagens de R. sanguineus têm implicações epidemiológicas, podendo afetar a competência vetorial de Ehrlichia canis, o agente etiológico da erliquiose monocítica canina. Com a intenção de identificar os microbiomas de ambas as linhagens e comparar microrganismos de R. sanguineus, foi utilizada a metataxonomia, baseada no gene 16S rRNA (região V4-V5), por meio do sequenciamento de nova geração na plataforma MiSeq Illumina. Foram selecionadas amostras de fêmeas do ambiente e cultivo primário de células embrionárias, considerando-se as duas linhagens conhecidas do Brasil. Este é o primeiro estudo que investiga o microbioma procariótico de células de cultura de carrapato. Os resultados mostram que muitos grupos de bactérias detectadas nas amostras são membros típicos do ambiente do hospedeiro. Uma diversidade significativa de microrganismos em fêmeas e cultura de células embrionárias nas duas linhagens de R. sanguineus foi encontrada, com ênfase na presença de Coxiella em todas as amostras, ainda que em diferentes proporções. Possivelmente, as espécies de Coxiella presentes nas duas linhagens de carrapatos são diferentes e co-evoluíram com essas linhagens, conduzindo a diferentes padrões de interação entre carrapatos e patógenos que podem abrigar ou transmitir aos hospedeiros vertebrados.(AU)


Assuntos
Animais , Feminino , Rhipicephalus sanguineus/embriologia , Rhipicephalus sanguineus/genética , Microbiota/genética , Coxiella/classificação , Coxiella/genética , Ehrlichiose
17.
Rev. bras. reprod. anim ; 45(4): 583-589, out.-dez. 2021.
Artigo em Inglês | VETINDEX | ID: biblio-1492712

Resumo

O estresse por calor (ET) ocorre quando a temperatura ambiente excede a zona de conforto térmico animal. Várias respostas corporais inespecíficas, capitaneadas pelos sistemas nervoso, neuroendócrino e imunológico são acionadas para manter a homeostase e resfriar o animal. O ET afeta o eixo hipotálamo-hipofisário-gonadal, comprometendo a liberação de gonadotrofinas, e promove o acúmulo de espécies reativas de oxigênio e proteínas anormais nas células ovarianas. Em resposta, as células ativam mecanismos antioxidantes e de reparação do DNA, que reduzem o metabolismo celular e aumentam as chances de sobrevivência; quando a reparação não é possível, acontece a apoptose. O ET impacta negativamente a produção de estradiol ovariano, o comportamento do estro, o desenvolvimento folicular, a competência dos oócitos e do embrião, as taxas de concepção, o estabelecimento e a manutenção da gravidez e até mesmo a eficiência reprodutiva da progênie. O combate ao ET inclui estratégias de combate ao aquecimento global progressivo e de manejo para resfriar os animais, e diminuir a produção de calor metabólico. O uso de biotecnologia reprodutiva e estratégias genéticas para gerar animais termotolerantes são também essenciais


Heat stress (HS), a harmful condition affecting animal production, reproduction, and welfare, occurs when an animal is exposed to temperatures that exceed its thermal comfort zone. Several nonspecific body responses involving neural, neuroendocrine, and immune systems are triggered to keep homeostasis in such conditions. These responses, primarily directed to cooling the body, also impact the hypothalamic-pituitary-gonadal axis, compromising the bovine female’s release of gonadotropins. Heat stress also promotes reactive oxygen species accumulation in ovarian cells, impairing protein folding and refolding, triggering antioxidant and DNA protection mechanisms. These mechanisms, directed to reduce cell metabolism and increase survival chances, are not always sufficient to protect the cell and result in apoptosis. Heat stress’s systemic and cellular consequences impact ovarian estradiol production, estrous behaviors, follicular development, oocytes and embryo competence, conception rates, pregnancy establishment and maintenance, and even the future reproductive efficiency of the progenies of cows exposed to HS during pregnancy. The combat of heat stress includes strategies to alleviate the effect of progressive global warming, management strategies to cool the animals, reduced metabolic heat, and methane production dietary approaches. The use of reproductive biotechs and genetic strategies to increase thermotolerant animals are also critical to overcoming the harmful effect of HS.


Assuntos
Feminino , Animais , Bovinos , Bovinos/fisiologia , Comportamento Reprodutivo , Transtornos de Estresse por Calor , Eficiência
18.
Acta sci. vet. (Impr.) ; 49(supl.1): Pub. 687, 2021. ilus, tab
Artigo em Inglês | VETINDEX | ID: biblio-1363214

Resumo

Background: Canine vector borne diseases (CVBD) are common in tropical countries where the climate favors arthropods abundance. Comorbidity with one or more CVBD are reported as clinical complication and worsen prognostic. Canine visceral leishmaniosis (CanL) is an endemic zoonotic disease in Brazil caused by Leishmania infantum, with several restrictions to canine treatment and suggestion of reservoirs euthanasia for disease control. Heartworm (HW) is a helminthic disease caused by Dirofilaria immitis infection in dogs. It is a chronic heart disease, which can lead to death by congestive heart failure. Canine ehrlichiosis (CE) is caused by Ehrlichia canis bacterial infection with a zoonotic potential and fatal to dogs in acute and chronic presentations. Exposed the above, this study aims to describe a successful treatment and management of a dog with CanL, CE, and HW comorbidity. Case: A 3-year-old male uncastrated black Labrador dog, weighing 35 kg, was admitted to the veterinary clinic due to immunochromatographic CanL positive test performed by municipal zoonosis control center active surveillance. Clinical exam showed a mild shedding, intermittent eye white/yellow discharge and popliteal lymph nodes enlargement. After positive for CanL, veterinary requested more laboratorial exams. IFAT and ELISA were positive for CanL, blood smear showed presence of microfilaria, and bone marrow cytology showed Ehrlichia spp. morulae and microfilaria. Initial treatment prescribed was oral doxycycline, omeprazole, ranitidine, and domperidone for 30 days, and allopurinol and ivermectin until further recommendation. Additionally, repellent collar, repellent spray and vitamin supplement was indicated. After first month, marbofloxacin for 30 days and three doses of immunostimulant drug were administrated. After three months of treatment, dog still positive for heartworm, ehrlichiosis, and CanL. Doxycycline protocol was repeated. Dog became consistently negative for all pathogens one year later with persistent thrombocytopenia but without clinical signs, ergo allopurinol and ivermectin were discontinued. After 4 years of follow up, the animal had an acute pancreatitis and died, with unremarkable total blood count and negative for all pathogens. Discussion: CVBD coinfections are commonly reported as worsen prognostic in endemic regions. The pathogens reported here share a host immunomodulation competence. L. infantum and Ehrlichia spp. downregulates Th1 response, whereas D. immitis increase as Th2 profile. The therapeutic protocol was iniciated by staging CanL. Since the patient had clinical signs, allopurinol was prescribed as a well-established drug for CanL. Marbofloxacin was added due to its high safety drug in clinical improvement of infected dogs with and without renal disease and in vitro effectiveness against L. infantum. Domperidone was used to promote Th1 cytokine profile as INF-γ, IL-2, IL-12, and TNF-α. We used an immunostimulant protocol to favor polarization to the Th1 profile comprised by 30 days of domperidone protocol followed by a vaccine and an immunomodulator. Doxycycline was used successfully for Ehrlichia spp. and HE clearance after 2 treatment courses and 1 year of ivermectin every 15 days. The animal presented intermittent coughing episodes on the first treatment course, but no medical intervention was needed besides exercise restriction. Our report shows the successful management of one dog with CanL, CE and HE comorbidity. This success was possible due to early detection and good therapeutic choice.(AU)


Assuntos
Animais , Masculino , Cães , Ehrlichiose/terapia , Ehrlichiose/veterinária , Dirofilariose/terapia , Coinfecção/veterinária , Leishmaniose Visceral/terapia , Leishmaniose Visceral/veterinária , Leishmania infantum/isolamento & purificação , Ehrlichia canis/isolamento & purificação , Dirofilaria immitis/isolamento & purificação , Doenças Transmitidas por Vetores/veterinária
19.
Ciênc. Anim. (Impr.) ; 30(4): 77-91, 2020. tab
Artigo em Português | VETINDEX | ID: biblio-1472667

Resumo

A domesticação alterou significativamente a capacidade cognitiva dos cães e permitiu que certos comportamentos sociais fossem selecionados e garantissem uma grande variação de possibilidades na organização e interação social destes animais. Juntamente com o diferencial de um ambiente compartilhado com a espécie humana, e diante do crescente interesse científico em compreender a cognição canina, vários modelos teóricos têm sido utilizados para respaldar a dinâmica da organização social canina, incluindo nossa relação com eles. Desde os primeiros modelos estabelecidos pela Etologia, inspirados na teoria transicional, até o modelo de hierarquia de dominância, as atuais tentativas de explicar a complexidade social canina parecem distantes de solucionar ou equalizar o que as evidências científicas vêm demonstrando sobre esta espécie em termos sociais. Mesmo após a desconstrução dos modelos de dominância, até o surgimento de alternativas teóricas, a emergência de teorias que possam formular uma nova visão que atenda a complexidade social dos cães é necessária Diante disso, este artigo propôs uma discussão da organização social canina na perspectiva do Behaviorismo Radical de Skinner, para a construção de um modelo denominado contingencial. Tal modelo pressupõe a capacidade múltipla dos cães em adaptar-se ao ambiente social partilhado com o homem e a partir da teoria Comportamental estabelecer as bases das dinâmicas sociais envolvendo a organização intra e interespécie por meio das habilidades sociais que irão compor os efeitos contingenciais sociais.


Domestication significantly altered the dogs' cognitive ability and allowed certain social behaviors to be selected and guaranteed a wide range of possibilities in the organization and social interaction of these animals. Along with the differential of an environment shared with the human species, and given the growing scientific interest in understanding canine cognition, several theoretical models have been used to support the dynamics of canine social organization, including our relationship with them. From the first models established by Ethology, inspired by the transitional theory, to the hierarchy model of dominance, current attempts to explain canine social complexity seem far from solving or equalizing what scientific evidence has been demonstrating about this species in social terms. Even after the deconstruction of dominance models, until the emergence of theoretical alternatives, the emergence of theories that can formulate a new vision that meets the social complexity of dogs is necessary. In view of this, this article proposed a discussion of the canine social organization from the perspective of Skinner's Radical Behaviorism, for the construction of a model called contingency. Such a model presupposes the multiple ability of dogs to adapt to the social environment shared with man and, based on Behavioral Theory, to establish the bases of social dynamics involving intra and interspecies organization through the social skills that will compose the contingent social effects.


Assuntos
Animais , Cães , Animais Domésticos , Comportamento Animal , Habilidades Sociais , Organização Social
20.
Ciênc. Anim. (Impr.) ; 30(4): 77-91, 2020. tab
Artigo em Português | VETINDEX | ID: vti-29986

Resumo

A domesticação alterou significativamente a capacidade cognitiva dos cães e permitiu que certos comportamentos sociais fossem selecionados e garantissem uma grande variação de possibilidades na organização e interação social destes animais. Juntamente com o diferencial de um ambiente compartilhado com a espécie humana, e diante do crescente interesse científico em compreender a cognição canina, vários modelos teóricos têm sido utilizados para respaldar a dinâmica da organização social canina, incluindo nossa relação com eles. Desde os primeiros modelos estabelecidos pela Etologia, inspirados na teoria transicional, até o modelo de hierarquia de dominância, as atuais tentativas de explicar a complexidade social canina parecem distantes de solucionar ou equalizar o que as evidências científicas vêm demonstrando sobre esta espécie em termos sociais. Mesmo após a desconstrução dos modelos de dominância, até o surgimento de alternativas teóricas, a emergência de teorias que possam formular uma nova visão que atenda a complexidade social dos cães é necessária Diante disso, este artigo propôs uma discussão da organização social canina na perspectiva do Behaviorismo Radical de Skinner, para a construção de um modelo denominado contingencial. Tal modelo pressupõe a capacidade múltipla dos cães em adaptar-se ao ambiente social partilhado com o homem e a partir da teoria Comportamental estabelecer as bases das dinâmicas sociais envolvendo a organização intra e interespécie por meio das habilidades sociais que irão compor os efeitos contingenciais sociais.(AU)


Domestication significantly altered the dogs' cognitive ability and allowed certain social behaviors to be selected and guaranteed a wide range of possibilities in the organization and social interaction of these animals. Along with the differential of an environment shared with the human species, and given the growing scientific interest in understanding canine cognition, several theoretical models have been used to support the dynamics of canine social organization, including our relationship with them. From the first models established by Ethology, inspired by the transitional theory, to the hierarchy model of dominance, current attempts to explain canine social complexity seem far from solving or equalizing what scientific evidence has been demonstrating about this species in social terms. Even after the deconstruction of dominance models, until the emergence of theoretical alternatives, the emergence of theories that can formulate a new vision that meets the social complexity of dogs is necessary. In view of this, this article proposed a discussion of the canine social organization from the perspective of Skinner's Radical Behaviorism, for the construction of a model called contingency. Such a model presupposes the multiple ability of dogs to adapt to the social environment shared with man and, based on Behavioral Theory, to establish the bases of social dynamics involving intra and interspecies organization through the social skills that will compose the contingent social effects.(AU)


Assuntos
Animais , Cães , Comportamento Animal , Animais Domésticos , Organização Social , Habilidades Sociais
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