Effects of amylin on egg quality traits of hens during the early laying period

This study was conducted to investigate the effects of amylin, a pancreatic hormone polypeptide, on egg quality traits in laying hens. A total of 40 birds (14 wk of age) were randomly divided into two treatments with two replicates, 10 birds in each replicate. Twenty birds were subcutaneously injected with amylin at 75 µg/kg every other day (treatment 1), and the remaining animals (20 hens) were given only water as the control group (treatment 2). Eggs collected from the two groups (140 eggs per group) were examined for several quality performance traits such as egg weight, specific gravity, shape index, eggshell strength, eggshell thickness, eggshell ash, eggshell weight, Haugh unit (HU), albumen index, yolk index, yolk color, and albumen height. The results indicated that amylin had a positive effect on some egg quality traits in laying hens. Specific gravity, eggshell thickness, eggshell weight, HU, albumen index, yolk index, and albumen height, which are all considered as important quality parameters from the consumer point of view, especially HU, were relatively improved in the amylin treatment group. These results showed that the injection of 75 µg/kg amylin has a significant effect on some egg quality traits. Considering that egg quality characteristics are crucial for the egg industry, this study can be a reference for the detailed investigation of the use of amylin in the different stages of egg production.

Effect of the Line and Age of Female Broiler Breeder on Hatchability Performance of Eggs

An experiment was conducted to assess how hatchability performance of eggs is affected by line and age of female broiler breeders. Response variables analyzed were hatchability, infertility, pipping (i.e., pipped shell but not emerged), embryonic mortality (1st, 2nd, and 3rd wk), and embryonic malposition. The trials involved a total of 2,880 fertile eggs from two broiler breeder lines (Ross 308 and Cobb 500) at two different ages (30 and 50 wk). A 2 x 2 factorial design was used, where the broiler breeder line and broiler breeder age were the main effects. The hatchability in the Ross 308 line was higher than the Cobb 500 line, but its infertility was higher than the Ross 308 line. Hatchability in interaction (50 wk age of the hen in the Cobb 500 line) was less, and their infertility was higher. Embryonic mortality, pipping, and embryonic malposition did not present differences for the interaction between factors. The results suggest that hatchability performance of eggs can be improved, if egg management and incubation procedures are adjusted to account for the interaction between broiler breeder line and broiler breeder age.(AU)

Diferentes densidades de alojamento de galinhas poedeiras em gaiolas e suas respectivas produção, qualidade de ovos e escore de penas / Different housing densities of laying hens in cages and their production, egg quality andfeather score

As poedeiras criadas em sistema degaiolas tem seu bem-estar afetado devido ao menor espaço disponível para elas, o que vai de encontro da crescente pressão por grande parte de consumidores preocupados com as condições em que essas aves são criadas. A consequência dessa menor densidade de alojamento sobre a produtividade, e a qualidade de vida da ave e dos ovos por elas produzidos deve ser avaliada. O objetivo desse estudo é avaliar a produção, qualidade de ovos, e bem-estar de galinhas poedeiras criadas em diferentes densidades de alojamentos em gaiolas. Às 28 semanas de idade, foram distribuídas, em delineamento inteiramente casualizado, 120 poedeiras leves da linhagem Novogen White, após debicagem, em 24 gaiolas com dimensões de 45 cm x 50cm, em três diferentes densidades de alojamento: 562,5 cm² /ave (quatro aves/gaiola), 450 cm² /ave (cinco aves/gaiola) e 375 cm² /ave(seis aves/gaiola), com 8 repetições cada. As dietas experimentais foram isoproteicas e isoenergéticas, formuladas à base de milho e farelo de soja. O período experimental será compreendido por seis ciclos de 28 dias cada. As variáveis analisadas foram: peso do ovo, índice de gema, unidade Haugh, pigmentação da gema, porcentagem dos componentes dos ovos e espessura de casca (em milímetros). Quando as aves atingiram 44 semanas de idade, foi realizada a medição do escore de penas. Foram avaliadas 40 galinhaspor tratamento, em quatro regiões: peito, dorso, asas e posterior. Essa análise consiste emcategorizar as aves de acordo com três diferentes escores, de acordo com o tamanho da área de ausência de penas em cada região. Espera-se que a redução da densidade de alojamento das galinhas nas gaiolas propicie maior produção com melhor qualidade dos ovos, promovendo também melhor bem-estar das aves.(AU)

The well-beingof laying hens raised in cages is affected due to the smaller space available for them,which is in line with the growing pressure from a large number of consumers concerned about the conditions in which these birds are raised.The consequence of thislower housing density on productivity and the quality of life of the bird andthe eggs produced by them must be evaluated. The aim of this study is to evaluate the production, egg quality, and welfare of laying hens reared in different housing densities in cages. At 28 weeks of age, 120 light Novogen White laying hens were distributed, after beak trimming, in24 cages measuring 45 cm x 50 cm, in three different housing densities: 562.5 cm²/bird (four birds/cage), 450 cm²/bird (five birds/cage) and 375 cm²/bird (six birds/cage), with 8 repetitions each. The experimental diets were isoproteic and isoenergetic, based on corn and soybean meal. The trial period will comprise six cycles of 28 days each. The variables analyzed were: egg weight, yolk index, Haugh unit, yolk pigmentation, percentage of egg components and shell thickness (in millimeters). When the birds reached 44 weeks of age, the feather score was measured. Forty chickens per treatment were evaluated in four regions: chest, back, wings and hindquarters. This analysis consists of categorizing the birds according to three different scores, according to thesize of the area without feathers in each region. It is expected that the reduction in the hen housing density in the cages will lead to higher production with better egg quality, also promoting better hen welfare.(AU)

Effect of monochrome light with different wavelengths on biochemical parameters of hens

Artificial light, as one of the environmental factors, plays a significant role in regulating the synthesis and secretion of hormones related to the coordination of parameters of life, growth, immunity, and reproductive functions of hens. The article aims to study the influence of monochrome light with different wavelengths on the biochemical parameters of hens` blood serum. Four groups of "Hy-Line W-36" crossbred hens were formed. Hens of the 1st group were kept using monochrome light with different wavelength lamps with a wavelength of ~ 460 nm, the 2nd group ~ 600 nm, the 3rd group ~ 630 nm, and the 4th group ~ 650 nm. It was found that the use of light with different wavelengths for keeping hens in cages of multilevel batteries affects hen' biochemical parameters, according to the research results. It was established that when using light with a wavelength of ~ 630 and ~ 650 nm, the indicators of clinical biochemistry of hens' blood serum were within the normal physiological values. Whereas, with the use of light with a wavelength of ~ 600 nm, an increase in the level of glucose, creatinine, total protein, total bilirubin, and phosphorus, a decrease in the ratio of calcium to phosphorus, in the activity of alkaline phosphatase, aspartate aminotransferase, and lactate dehydrogenase, were observed in the hens' blood serum. The use of light with a wavelength of ~ 460 nm was accompanied by a further increase in the level of glucose, creatinine, total protein, urea, total bilirubin, phosphorus, the activity of alkaline phosphatase, aspartate aminotransferase, lactate dehydrogenase, and gamma-glutamyltransferase, a decrease in the ratio of calcium and phosphorus.

Ascaridia galli: A report of erratic migration in eggs for human consumption in Bucaramanga, Colombia - case report / Ascaridia galli: Um relatório de migração errática em ovos para consumo humano em Bucaramanga, Colômbia - relato de caso

This case report describes how an erratic specimen of Ascaridia galli in the adult phase was recovered in an unusual way from a hen's egg intended for human consumption. Although the literature on similar events is limited, this appears to be the first case reported in Bucaramanga, Colombia. The parasite was identified directly under a light microscope as an adult female A. galli, 6.5-cm long with 3 trilobed lips. In addition, the remaining eggs of the same group were examined to determine if there were more cases of erratic migration in that same batch. This nematode can cause various pathological conditions, including enteritis, hemorrhage, diarrhea, anemia, weakness, and emaciation, that can lead to huge economic and production losses in the poultry industry.

Este relato de caso descreve como um exemplar errático de Ascaridia galli na fase adulta foi recuperado de uma forma incomum em um ovo de galinha destinado ao consumo humano. Embora a literatura sobre eventos similares seja limitada, este parece ser o primeiro caso relatado em Bucaramanga, Colômbia. O parasita foi identificado diretamente sob um microscópio leve como uma fêmea adulta A. galli, com 6,5 cm de comprimento e 3 lábios trilobados. Além disso, os ovos restantes do mesmo grupo foram examinados para determinar se existiam mais casos de migração errática nesse mesmo lote. Este nemátodo pode causar várias condições patológicas, incluindo enterite, hemorragia, diarréia, anemia, fraqueza e emaciação, que podem levar a enormes perdas econômicas e de produção na indústria avícola.

Cutaneous myxoma in broiler chicken detected during slaughtering

Background: A cutaneous or superficial myxoma is a benign neoplasm of dermal or subcutaneous fibroblast origin. Although rare, it has been previously described in several species, including poultry. It presents as a single node or soft mass with a gelatinous cut surface. Histopathological analysis is essential for diagnosis and to differentiate it from other mesenchymal neoplasms and inflammatory or degenerative processes. Microscopically, it consists of dermal or subcutaneous lobules of plump, stellate, or spindle-shaped, bland-looking cells embedded in a basophilic myxoid matrix. This report describes the pathological findings in a rare case of cutaneous myxoma in a 42-day-old broiler flock. Cases: During ante mortem inspection of a 42-day-old broiler flock at a slaughterhouse under the authority of the Federal Inspection Service (southern Brazil), nodular lesions or encrusted areas with yellow and black areas were observed in the head skin of less than 1% of animals. These lesions, approximately 0.5 cm in diameter, were observed on the comb, in the periocular skin region, and close to the animals' nostrils. During the breeding period, no health or epidemiological events were observed. Fragments of the lesions in the comb and periocular skin were collected and fixed in buffered 10% formalin. The samples were sent to the laboratory, routinely processed, and stained with hematoxylin and eosin and Alcian blue. Microscopically, the lesions consisted of irregular multifocal proliferation of connective tissue showing spindle cells with poorly demarcated borders and scarce cytoplasm in a slightly basophilic myxoid aspect matrix. The adjacent epidermis is compressed due to neoplastic proliferation. No areas of epithelial hyperplasia or inclusion bodies were observed. According to the pathologic description and considering its descriptive epidemiology, our main clinical suspicion was cutaneous fowl pox, a pathology characterized by the appearance of nodules in regions devoid of feathers. However, the microscopic changes observed were compatible with those described for cutaneous myxomas. In addition, the extracellular matrix was positive for Alcian Blue staining, which is an indicator of myxoma. In the present case, the SIF did not report the same macroscopic lesions in other flocks of the same origin. Discussion: Connective tissue tumors, including myxomas, occur considerably less frequently under field conditions. In addition, these neoplasms are more frequent in mature birds and are not usually described in broilers, as observed in this report. The cutaneous myxoma described in broilers is usually a sporadic neoplasm that does not cause zootechnical losses, as observed in the case report. Its etiology is unknown and has been associated with various factors, such as local trauma and foreign bodies. Some fragments of plant material from the breeding environment were microscopically detected in the encrusted areas, which may indicate previous trauma or a foreign body. Myxoma has been associated with avian leukosis virus (ALV) subgroup A, but SIF did not report the same macroscopic lesions in other flocks of the same breeder hen's origin in the present case. Furthermore, sporadic connective tissue tumors associated with the virus occur in mature chickens but not in broilers. Myxoma lesions should be considered in the differential diagnosis of other connective tissue tumors and infectious agents that cause lesions in the skin and subcutaneous tissue.

Voracity, reaction to stings, and survival of domestic hens when feeding on the yellow scorpion (Tityus serrulatus)

Abstract Background: Scorpionism is a worldwide problem that has already made thousands of victims, and multi-disciplinary approaches for controlling their populations are to be more successful. Hens are often mentioned as tools for controlling scorpions; however, systematic/experimental behavioral studies are not available. Moreover, there is no systematic information on the effect of scorpion venoms on hens. Using the venomous yellow scorpion Tityus serrulatus, the present study aimed to clarify the following aspects: (1) voracity of hens, (2) how hens react when stung, (3) the effect of scorpion stings on hen behavior during attacks, and (4) hen survivorship after feeding on scorpions. Methods: We attracted hens with corn powder, offered them scorpions and then recorded the hen-scorpion interaction. To test the effects of the sting we manually removed the scorpions telson. Results: We found that some hens ate up to six scorpions within minutes. By means of an ethogram and drawings, we showed that they exhibited several aversive behaviors when capturing scorpions. Removal of the scorpion telson stopped the aversive reactions, which was not observed in the control group. Finally, hens did not exhibit atypical behaviors after 1, 7 and 30 days and were all alive after 30 days. Conclusion: This is the first empirical and video recorded study providing evidence that hens are clearly affected by scorpion venom but do not die. Therefore, they may have potential to be used in biological control of these arthropods.

Multivariate analysis of sources of polyunsaturated fatty acids, selenium, and chromium on the productive performance of second-cycle laying hens

An experiment was conducted to evaluate the effect of the intake of a mixture of fish and sacha inchi oils (iOM), organic selenium (iSe), and organic chromium (iCr) on egg production (EP) and feed conversion ratio (FCR) of Isa Brown second-cycle laying hens (SCLH) for 16 weeks (91-106 weeks old). Egg production and FCR were evaluated using multivariate models that included conventional equations and artificial neural networks (ANN) to study multiple nutritional interactions as alternatives to univariate dose-response models. Based on the best models, iOM, iSe, and iCr levels were optimized, and a global sensitivity analysis was implemented to quantify their influence on EP and FCR. The modified logistic model was selected as the best strategy to represent EP. In the case of FCR, an ANN model with a feed-forward architecture and softmax transfer function was selected as the best alternative. One of the scenarios to simultaneously optimize EP (89.1%) and FCR (1.94 kg feed/kg egg) at 16 weeks of production was established with 3.3 g/hen·day of iOM, 0.132 mg/ hen·day of iSe, and 0.176 mg/hen·day of iCr. However, optimization considering only FCR results in much lower optimal iCr levels (between 0.083 and 0.105 mg/hen·day) with a slight decrease in EP (87.9%). The global sensitivity analysis showed that iSe is an essential factor associated with the increase in EP, and iCr is the most influential factor for the decrease in FCR. When both criteria were taken into account simultaneously from a desirability function, iSe was the most critical factor.(AU)

Voracity, reaction to stings, and survival of domestic hens when feeding on the yellow scorpion (Tityus serrulatus)

Scorpionism is a worldwide problem that has already made thousands of victims, and multi-disciplinary approaches for controlling their populations are to be more successful. Hens are often mentioned as tools for controlling scorpions; however, systematic/experimental behavioral studies are not available. Moreover, there is no systematic information on the effect of scorpion venoms on hens. Using the venomous yellow scorpion Tityus serrulatus, the present study aimed to clarify the following aspects: (1) voracity of hens, (2) how hens react when stung, (3) the effect of scorpion stings on hen behavior during attacks, and (4) hen survivorship after feeding on scorpions. Methods: We attracted hens with corn powder, offered them scorpions and then recorded the hen-scorpion interaction. To test the effects of the sting we manually removed the scorpion's telson. Results: We found that some hens ate up to six scorpions within minutes. By means of an ethogram and drawings, we showed that they exhibited several aversive behaviors when capturing scorpions. Removal of the scorpion telson stopped the aversive reactions, which was not observed in the control group. Finally, hens did not exhibit atypical behaviors after 1, 7 and 30 days and were all alive after 30 days. Conclusion: This is the first empirical and video recorded study providing evidence that hens are clearly affected by scorpion venom but do not die. Therefore, they may have potential to be used in biological control of these arthropods.(AU)

Evaluation of Analytical Sensitivity of Sdf I based PCR and Sandwich ELISA for Salmonella Enteritidis detection and On-Farm prevalence in Punjab, Pakistan

Salmonella Enteritidis (SE) is a dominant serotype among non-typhoidal Salmonella which renders poultry products unsafe for human consumption. Due to frequent reporting of egg associated outbreaks, broiler breeder flocks are understudied although farm environment present supporting conditions for the growth of SE. In this study, two rapid detection techniques for SE were compared in terms of analytical sensitivity and the extent of SE contamination in broiler breeder farm environment was determined. Analytical sensitivity as limit of detection (LOD) was evaluated quantitatively for serotype specific PCR based on amplification of Sdf I gene and a commercially available sandwich ELISA for antigen detection. In triplicate experiments, tenfold serial dilutions of SE were prepared and tested with each technique. Using pure cultures, analytical sensitivity of PCR and ELISA were found to be 18.6 CFU/ml and 2.77×105 CFU/ml respectively. PCR (LOD, log 1.2) was found to be more sensitive and rapid than ELISA (LOD, log 5.4). Environmental swab samples (n = 260) were collected from 22 hen houses representing 8 broiler breeder farms located in and around Lahore and Sheikhupura districts of Punjab province. From each hen house swab samples were collected from litter, nests, feeders, drinkers, fans, pads, ceiling, walls and walkways. Following selective enrichment, pooled swab samples were subjected to PCR. Results showed that 36.3 % (8/22) hen houses were detected positive for SE. These findings suggest improvement in farm biosecurity measures and advocate implementation of integrated Salmonellosis control programs in broiler breeder houses to minimize carcass contamination.(AU)

Assessment of coconut water added to Numida meleagris egg yolk as cryoprotectant for goat semen

Effects were assessed of the dilutants TRIS and ACP - 101c® with the addition of different guinea fowl (Numida meleagris) egg yolk concentrations. Fifteen ejaculates were collected from five goats of the Anglo Nubian breed. The ejaculates were pooled and then divided into 12 groups, two control groups (GC1 TRIS, with 2.5% Gallus gallus domesticus hen egg yolk GOGD), (GC2 Control Group ACP - 101c®, with the addition of 2.5% Gallus gallus domesticus hen egg yolk GOGD) and ten experimental groups (EG), containing TRIS and ACP added with different concentrations of egg yolk from guinea hen (Numida meleagris) (TRIS 2,5% GONM; TRIS 5% GONM; TRIS 10% GONM; TRIS 15% GONM; TRIS 20% GONM; ACP® 2,5% GONM; ACP® 5% GONM; ACP® 10% GONM; ACP® 15% GONM; ACP® 20% GONM). Then cryopreservation was carried out and the samples stored in liquid nitrogen (-196 °C). After seven days, the samples were thawed and assessed for spermatic kinetics, immunofluorescence and sperm morphology. Analysis of GOMN by the CASA system showed that the various parameters were similar to those of GOGD (P>0.05). The membrane integrity, mitochondrial potential and the acrosome were not influenced by the treatment (P>0.05) nor by the dilutant used for cryopreservation (P>0.05). The spermatic morphology was also preserved by the different GOGD and GONM concentrations in the ACP® and TRIS dilutants, with no statistically significant differences (P<0.05). It was concluded that Numida meleagris egg yolk, as external membrane cryoproctant added to the dilutants ACP-101c® and TRIS, improved goat semen quality.(AU)

Use of Mathematical Models in the Analysis of Growth and Commercial Performance of Brown Layers

Small and medium-sized table egg producers have a large volume of data and information on daily production, which is not used in the decision-making process. It is important to define the best mathematical model for the prediction of both the growth and the egg production of brown layers to relate pullet growth traits with productivity in a commercial cycle. For the above purpose, growth and production data were obtained from 15 brown layer flocks, six mathematical models of growth and five of egg production were tested. Correlations were made between the parameters of growth and egg production, as well as between the parameters derived from the mathematical models. The prediction equations for the egg production indicators were estimated.As a result,the best model for predicting layer growth (Gompertz) and for egg production was obtained (Yang). The growth parameters with the greatest influence on egg production were the maximum growth rate (MGR) and the theta value (TV). Body weight at 8, 9, 10, 12, and 16 weeks of age had effects on egg production. As a conclusion maximizing the growth of the brown layer in key stages of its development has positive effects on egg production.(AU)

Thermal environment characterization of laying hen-housing systems

This study systematically collected data on variables that influence the thermal environment characteristics in poultry houses. Laying poultry farming is a relevant economic activity in Brazilian agriculture and has been expressively growing mainly regarding genetics and nutrition. Thermal comfort in poultry houses is needed to achieve poultry's maximum productive potential. Therefore, laying aviaries previously naturally ventilated (positive pressure) are starting to be equipped with cage batteries and designed with lateral closures, using negative pressure ventilation and in some cases associated with adiabatic cooling. However, negative pressure ventilation systems' thermal efficiency in tunnel mode and its distribution in different cage levels is still slightly known. Consequently, this system's thermal efficiency needs to be investigated to ensure adequate climate indices recommendations and avoid costs and losses due to inadequate handling and facilities.

Behavior of domestic chickens: insights from a narrative review / Comportamento de galinhas domésticas: percepções de uma revisão narrativa

The intensification of poultry production systems has brought major changes in domestic fowls' physical and social environment. The management of these birds has received considerable attention in recent years due to new demands from consumers, especially those related to welfare. Behavior is the way that animals respond to the different stimuli they encounter in their environment. The behavioral expressions of poultry and the application of this knowledge in the care of the stock plays an important part in the maximization of the production efficiency of the poultry chain. Thus, defining ethical limits and guidelines for poultry production is essential to promote the development of new production practices, and by that ensure quality and productivity without putting bird welfare at risk. This review is based on scientific literature and highlights the main behavioral expressions of domestic chickens, including social, feeding, and reproductive expressions, in addition to stereotypes and strategies for social adaptation. Thus, it will promote to the reader and for the scientific community a better understanding about subjects that are not frequently discussed and by that help behavioral analyzes.

A intensificação do sistema de produção avícola trouxe profundas mudanças no ambiente físico e social das aves domésticas. O manejo dessas aves tem recebido considerável atenção nos últimos anos devido às novas demandas por parte dos consumidores, principalmente aquelas relacionadas ao bem-estar. O comportamento é a maneira como os animais respondem aos diferentes estímulos que encontram em seu ambiente. As expressões comportamentais das aves domésticas e a aplicação desse conhecimento no cuidado dos animais desempenha um papel importante na maximização da eficiência de produção da cadeia avícola. Assim, definir limites éticos e diretrizes para a produção avícola é fundamental para fomentar o desenvolvimento de novas práticas produtivas, e assim garantir qualidade e produtividade sem colocar em risco o bem-estar dos animais. Esta revisão destacará as principais expressões comportamentais das aves domésticas, dentre elas as expressões sociais, alimentares, reprodutivas, além de estereotipias, e identificará as estratégias de adaptação social. Assim, promovera ao leitor e a comunidade científica uma melhor compreensão de assuntos pouco discutidos para assim auxiliar em análises comportamentais.

The Protective Role of Silymarin to Ameliorate the Adverse Effects of Ochratoxin-A in Laying Hens on Productive Performance, Blood Biochemistry, Hematological and Antioxidants Status

This study was planned to examine the effect of silymarin on diminishing adverse effects of ochratoxin-A (OTA) in laying hens. A total number of 300 Inshas, local layer hens of 28 weeks of age were randomly distributed into 4 groups with 5 replicates each (15 hens). The birds were fed on the following treatments, (Control): fed a hen diet without any supplementation; (SL): fed the control diet supplemented with SL (1000 mg/kg feed); (OTA-diet): was fed the control diet contaminated with 1 ppm of OTA/kg diet, and (OTA+SL): fed the OTA-diet plus SL (1ppm OTA+1000 mg SL/kg feed). Results showed that feeding OTA at 1 ppm reduced productive performance compared with those fed the control diet. In OTA treated groups the total erythrocytes count, leukocytes count, PCV and Hb were decreased when compared to the control and SL groups. Albumin, globulin and serum total proteins in OTA treated groups were significantly lower when compared to the control and SL groups. Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were significantly increased in OTA fed groups in comparison with the control and SL groups. Creatinine and uric acid were increased in OTA treated groups but were almost normal in the SL group. The results showed that OTA had a severe effect on liver and kidney, but SL treated group had normal liver and kidneys showing its hepatoprotective effects.(AU)

A five-year surveillance study of vaccination schedules using viral-vectored vaccines against infectious laryngotracheitis in a high-density layer region / Cinco anos de monitoramento de esquemas vacinais com vacinas virais vetorizadas contra laringotraqueíte infecciosa em uma região altamente povoada por galinhas poedeiras

The effectiveness of vectored recombinant vaccines to control infectious laryngotracheitis (ILT) in chickens from a region (State of Minas Gerais, Brazil) with ~10 million layers was evaluated under field conditions from 2014-2018. During this period, only recombinant turkey herpesvirus (rHVT) or fowl poxvirus (rFPV) vaccines that express antigens of infectious laryngotracheitis virus (Gallid herpesvirus-1; GaHV-1) were used. Layer chickens (n=1,283), from eight different egg-producing companies, were individually sampled and examined (active surveillance), and in instances when government poultry health veterinarians were notified due to respiratory disease (passive surveillance). Clinical, macroscopic, and histopathology examinations were performed to diagnose ILT as well as molecular techniques for the detection and characterization of the GaHV-1 DNA from the trachea and trigeminal ganglia (TG). The layer hens sampled and examined belonged to flocks and farms that used different vaccination protocols (non-vaccinated, single dose vaccination, and prime/ boost vaccination). This is the first long-term field study of the effectiveness of ILT vectored vaccines in a high-density multiple age layer hen region. Using various diagnostic methods, the occurrence of GaHV-1 infection and ILT clinical disease in layer hens vaccinated with vectored recombinant vaccines in one quarantined region of Brazil were investigated. The number of ILTV positive chickens by PCR and ILT clinical disease cases was lower in farms when all chickens were vaccinated with at least one vaccine. However, the difference in the detection rates of GaHV-1 infection was significant only when compared farms with prime/ boost and farms using single dose of HTV-LT.

A efetividade das vacinas recombinantes vetorizadas para o controle da laringotraqueíte infecciosa (LTI) nas aves de uma região (Minas Gerais, Brasil) com aproximadamente 10 milhões de poedeiras foi avaliada em condições de campo, no período de 2014 a 2018. Durante este período, somente as vacinas recombinantes "turkey herpesvirus" (rHVT) ou "fowl poxvirus" (rFPV), que expressam antígenos do vírus da laringotraqueíte (Gallid herpesvirus-1; GaHV-1) foram utilizadas. Galinhas poedeiras (n=1.283), de oito diferentes granjas produtoras de ovos, foram individualmente amostradas e examinadas por monitoramento ativo e, na ocorrência de notificação de doença respiratória aos veterinários do serviço oficial, por monitoramento passivo. Exames clínicos, macroscópicos e histopatológicos foram realizados para o diagnóstico de LTI, bem como técnicas moleculares para a detecção e caracterização do DNA de GaHV-1 da traqueia e gânglio trigêmeo. As galinhas poedeiras pertenciam a lotes e granjas que usavam diferentes protocolos de vacinação (não vacinadas, uma dose ou tipo de vacina e duas doses ou tipos de vacina). Este é o primeiro longo estudo a campo sobre a efetividade das vacinas vetorizadas em uma região com população elevada de poedeiras de múltiplas idades. Utilizando vários métodos de diagnóstico, a ocorrência da infecção por GaHV-1 e a LTI clínica em poedeiras de uma região interditada do Brasil foi investigada. O número de galinhas positivas para o vírus GaHV-1 e para casos clínicos de LTI nas granjas foi menor quando todas as aves estavam vacinadas com, pelo menos, um tipo ou dose de vacina. Entretanto, a diferença na taxa de detecção da infecção por GaHV-1 foi significativa somente quando a comparação foi realizada entre granjas com aves vacinadas com duas doses e aves de granjas vacinadas com uma única dose de HVT-LT.

Effect of Dietary Tetramethylpyrazine on Egg Production, Nutrient Retention and Cecal Bacterial Diversity in Aged Laying Hens

This study aimed to investigate the effect of tetramethylpyrazine (TMP) supplementation on egg production, nutrient retention and cecal microbiota diversity using 288 commercial Hy-Line brown hens as of wk 75 to 86. Four treatments consisted of TMP addition at 0 (control, basal diet), 100, 150 and 200 mg/kg of diet. The results showed that diets supplemented with TMP addition improved egg-laying rate as of wk 77 compared to the control, which led to an increase (p<0.001) of egg mass by 97-225 g/hen throughout the whole trial, and a linear increase (p=0.003) of egg mass to the incremental TMP doses was found. At wk 86, the apparent digestibilities of dry matter and crude protein were enhanced (p<0.05), exhibiting consistent linear increases (p≤0.033) with the TMP doses. However, TMP did not cause alpha and beta diversity of cecal microbiota. The results suggest that TMP can be an additive to improve egg production and nutrient digestibility of aged laying hens.(AU)

Evaluation of actions of the official veterinary service to mitigate outbreaks of infectious laryngotracheitis and improve biosecurity on laying hen farms

ABSTRACT: Infectious laryngotracheitis (ILT), caused by an Alphaherpesvirus (Gallid herpesvirus-1; GaHV-1), has been noticed in the region of the Terras Altas da Mantiqueira, Minas Gerais. From 2010 to 2018, the Serviço Veterinário Oficial (SVO) of the Instituto Mineiro Agropecuário (IMA), implemented measures to prevent spread of the virus to other regions and control the disease in the area. Due to the close proximity and consequent epidemiological link among farms, the region was considered a unique epidemiological unit. To check the efficiency of the ILT control measures, we carried out: (1) a seroepidemiological survey, (2) questionnaires for evaluating biosecurity measures; and (3) an evaluation of the influence of farm population density on the occurrence of ILT. In 2016, 2017, and 2018, ILT was investigated using epidemiological and clinicopathological methods, along with GaHV-1 molecular detection. Serological survey was carried out on 24 farms in the quarantined region and on 13 farms from other regions of the state. In 2010 and 2018, questionnaires were applied to collect data and determine indicators of biosecurity practices in all farms of the quarantined area. The differences were then assessed (Wilcoxons p 0.05). The results indicated positive serology throughout the region, although only on four farms (16.6%) the chickens have clinical signs, macroscopic and histological lesions of ILT. The prevalence of viral infection increased from 2016 (27%) to 2017 (50%) and was higher in farms with a high stock density (p=0.033). No disease, virus or antibodies were detected in the farms outside of the quarantined area. Although the biosecurity indicators had improved on all farms in the quarantined area (p 0.05), the virus was active and circulating in the region. The contingency measures have contained the outbreak, but biosecurity practices are paramount in the control of new outbreaks. Official control will be maintained in the region, including surveillance of new cases and biosecurity procedures to mitigate the risk of the virus reaching other regions.

RESUMO: Laringotraqueíte infecciosa (LTI), causada por um alfaherpesvírus (herpesvírus Gallid-1; GaHV-1), foi observada na região das Terras Altas da Mantiqueira, Minas Gerais. De 2010 a 2018, o Serviço Veterinário Oficial (SVO) do Instituto Mineiro Agropecuário (IMA) implementou medidas para impedir a disseminação do vírus para outras regiões do estado e controlar a doença na região interditada. Devido à proximidade e consequente vínculo epidemiológico entre as granjas, a região foi considerada uma unidade epidemiológica única. Para verificar a eficiência das medidas de controle de LTI, foram realizados: (1) pesquisa soroepidemiológica, (2) questionários para avaliar medidas de biosseguridade; e (3) avaliação da influência da densidade populacional da granja na ocorrência de LTI. Em 2016, 2017 e 2018, a LTI foi investigada usando métodos epidemiológicos e clínico-patológicos, com a detecção molecular de GaHV-1. O levantamento sorológico foi realizado em 24 granjas da região interditada e em 13 granjas de outras regiões do estado. Em 2010 e 2018, foram aplicados questionários para coletar dados e determinar indicadores de medidas de biosseguridade em todas as granjas da área interditada. As diferenças foram avaliadas (p 0,05 de Wilcoxon). Os resultados indicaram sorologia positiva em toda a região, embora apenas em quatro granjas (16,6%) as galinhas apresentaram sinais clínicos, lesões macroscópicas e histológicas da LTI. A prevalência de infecção viral aumentou de 2016 (27%) para 2017 (50%) e foi maior em fazendas com alta densidade de alojamento (p=0,033). Presença da doença, vírus ou anticorpos foram detectados nas granjas fora da área interditada. Embora os indicadores de biosseguridade tenham melhorado em todas as fazendas da área interditada (p 0,05), o vírus está ativo e circulava na região. As medidas de contingência contiveram o surto, mas as práticas de biosseguridade são fundamentais para o controle de novos surtos. O controle oficial será mantido na região, incluindo a vigilância de novos casos e procedimentos de biosseguridade para mitigar o risco de transmissão do vírus para outras regiões.

Innate immunity in chicken lines developed by EMBRAPA Suínos e Aves: antimicrobial activity of macrophages and serum

The objective of this study was to compare the antimicrobial activity of macrophages and serum in laying hen (MM, CC, and CCc) and broiler chicken lineages (TT and LL). Macrophages were evaluated for phagocytic and antimicrobial activity. Microbicidal serum activity was evaluated by the resistance test for serum and the agar test. The results showed that phagocytic activity was higher in males of the MM strain, with 13% of macrophages presenting phagocytosis, while the other lineages studied, and even female MM, presented a rate of 6% of phagocytic cells. However, antimicrobial activity in macrophages from males of CCc lineage and females of TT lineage were higher, eliminating more than 30% of the Salmonella enterica inoculum, while in the other strains, the results were similar, with inoculum reduction below 30%. In the serum resistance assay, female laying lines presented higher antibacterial activity than female broiler lines. In the trials to evaluate the microbicide activity of the serum, females of both broiler and laying lineages presented higher performance when compared with males of the same lineage. Females of laying hen lines (MM and CC) present a greater antibacterium activity than males. These results can contribute to a better understanding of the immune response in broiler chicken and laying hen lineages, to aid development of lineages of birds more resistant to pathogens.

Production Layer Salmonella Enteritidis Control through Dry Fed Pre & Probiotic Products

ABSTRACT Increasing interest in multiple strain Bacillus probiotics and parietal yeast fractions as feed ingredients for egg laying hen diets has also led to food safety questions. This study was undertaken to evaluate the ability of these products to reduce Salmonella Enteritidis colonization. Sixty Hy-Line hens aged 56 weeks were placed in individual cages and fed a mash diet containing one of the following treatments, control, Bacillus spp. probiotic, yeast cell wall, or a combination of yeast cell wall and Bacillus probiotic. At 60 weeks of age all hens were challenged orally with 7 x 107 CFU/bird of Salmonella Enteritidis. At 61 weeks of age, birds were humanely euthanized, by cervical dislocation and the ceca aseptically removed and cultured for S. Enteritidis prevalence and number by the Most Probable Number method. There was no significant difference in prevalence of Salmonella Enteritidis between the control and any treatments. The control birds had 4.37 log10 MPN/g of S. Enteritidis detected in the ceca. The Probiotic group had 2.96 MPN/g, a reduction of 1.41(p 0.05) and the yeast cell wall group had 2.89 MPN/g a reduction of 1.48 (p 0.05). The combination had 3.60 MPN/g a numerical reduction of 0.78 (p=0.14). The yeast cell wall and Bacillus probiotic groups significantly reduced the amount of Salmonella Enteritidis in the ceca of the laying hens.