Effect of In Ovo Ascorbic Acid Injection and Thermal Manipulation During Incubation on Intestine Morphology of Broilers Reared under Cold and Heat Stress

It was investigated if pre-incubation ascorbic acid (AA) injection in fertile eggs incubated at high temperature impacts the performance, the yield of carcass and parts, and the intestine morphology of broilers reared under heat stress. Three thousand Cobb® fertile broiler eggs were randomly distributed according to weight into three incubations treatments (eggs not injected with AA and incubated at 37.5°C; eggs not injected with AA and incubated at 39°C; and eggs injected with 6 µg AA/100 µL water prior to incubation and incubated at 39ºC). The hatched birds were reared at thermoneutral, cold, and hot house temperatures. Broilers reared under hot temperature presented lower feed intake and weight gain than the broilers of the different rearing temperatures. Egg incubation at 39.0 ºC and 39.0 ºC + AA reduced broiler viability. Carcass and cut yields were not influenced by incubation and rearing procedures. Duodenal goblet cell count was lower in broilers from eggs of the treatment 39ºC + AA than in broilers from the other incubation treatments and in broiler rearing in hot temperature. In the jejunum, the goblet cell counts were higher in broilers that were reared under hot than thermoneutral temperatures. The incubation treatment of 39 ºC+AA increased the goblet cell counts in the ileum of broilers reared under cold temperatures. Rearing temperature influenced the duodenal villi counts, which were lower under cold rearing conditions than in the two other rearing temperatures. The results showed that egg incubation at 39°C, independently of ascorbic acid injection, did not produce an effective epigenetic heat adaptation in broilers.(AU)

Optimization Algorithm Applied to Environmental Control in Broiler Houses

The present study aimed to apply the Simulated Annealing (SA) optimization algorithm to find the ideal control of broiler housing rearing environment at 21, 28, 35, and 42 days of growth. Data from four types of houses using environmental control and similar flock density were recorded weekly in the morning and afternoon, during two seasons (summer and winter). The variables related to environmental and air quality data (temperature, relative humidity, air velocity, ammonia, and carbon dioxide concentrations) were registered and organized into the database to provide a descriptive analysis. The ideal rearing conditions were established as a goal, and we used the Simulated Annealing optimization algorithm to process the data. Such an approach may be applied in the cases that the ideal condition of optimization has multiple objectives, and when each variable is the result of a process. The model was implemented considering the optimal controlled environmental condition that depends on the age of broilers. Results indicated that there was a large dispersion of the data collected from the environmental variables. The process suggested that the optimized functions lead to absolute values obtained by the algorithm for each of the environmental factors of the controlled environmental system, representing the optimal condition of the environment found for each broiler age, considering the interactions of the variables. The maximum optimization was prominent to 21 and 35-d old birds, representing 40-48% of the improvement of the process. 28 and 42-d old birds might benefit from the controlled environmental optimization process by up to 30%.(AU)

Optimization Algorithm Applied to Environmental Control in Broiler Houses

The present study aimed to apply the Simulated Annealing (SA) optimization algorithm to find the ideal control of broiler housing rearing environment at 21, 28, 35, and 42 days of growth. Data from four types of houses using environmental control and similar flock density were recorded weekly in the morning and afternoon, during two seasons (summer and winter). The variables related to environmental and air quality data (temperature, relative humidity, air velocity, ammonia, and carbon dioxide concentrations) were registered and organized into the database to provide a descriptive analysis. The ideal rearing conditions were established as a goal, and we used the Simulated Annealing optimization algorithm to process the data. Such an approach may be applied in the cases that the ideal condition of optimization has multiple objectives, and when each variable is the result of a process. The model was implemented considering the optimal controlled environmental condition that depends on the age of broilers. Results indicated that there was a large dispersion of the data collected from the environmental variables. The process suggested that the optimized functions lead to absolute values obtained by the algorithm for each of the environmental factors of the controlled environmental system, representing the optimal condition of the environment found for each broiler age, considering the interactions of the variables. The maximum optimization was prominent to 21 and 35-d old birds, representing 40-48% of the improvement of the process. 28 and 42-d old birds might benefit from the controlled environmental optimization process by up to 30%.

Evolução da produção e exportação de frangos de corte no estado do Mato Grosso do Sul / Brazilian State of Mato Grosso do Sul broilers production and exports evolution

O objetivo do trabalho foi realizar um panorama evolutivo da cadeia de produção e exportação de frangos de corte no estado do Mato Grosso do Sul considerando o período de 2007 à 2016. Posteriormente se fez uma comparação dos resultados com os encontrados no estado do Paraná e um levantamento das barreiras comercias impostas à importação da carne de frango do Mato Grosso do Sul. A pesquisa se trata de uma análise descritiva e foram utilizados dados do InfoAgro, Secretária do Estado de Meio Ambiente, Desenvolvimento Econômico, Produção e Agricultura Familiar, Estatística de Comércio Exterior do Agronegócio Brasileiro e Associação Brasileira de Proteína Animal. Os resultados apontam que o setor encontra-se em evolução dentro do Mato Grosso do Sul, com crescimentos significativos na produção e exportação. O Paraná possui um crescimento superior ao do Mato Grosso do Sul no período avaliado, o que evidencia o potencial de crescimento do estado. Verificou-se que as barreiras à importação da carne de frango comerciais impostas ao Mato Grosso do Sul não influem significantemente no crescimento da cadeia avícola no estado, e que atualmente o mesmo atende a todas as exigências. Conclui-se que o estado do Mato Grosso do Sul necessita de tempo para que ocorra a consolidação da avicultura, e que para tanto se faz necessário incentivo do governo para atração de novas empresas e fortalecimento da atividade junto aos produtores do estado.

The aim of this work was to bring out an evolutionary panorama of the broilers production and export in the Mato Grosso do Sul state, considering the period between 2007 and 2016. Subsequently a survey was made for the commercial barriers imposed on the importation of Mato Grosso do Sul broiler meat. The research is a descriptive analysis and data from InfoAgro, Famasul System and Agrostat and the Brazilian Association of Animal Proteins. The results indicate that the sector is in evolution within the Mato Grosso do Sul, with significant increases in production and exports. Paraná has a higher growth than Mato Grosso do Sul in this evaluated period, which shows the growth potential of the state. It has also been found that the barriers to the importation of commercial broiler meat, imposed on the MS do not influence significantly the growth of the poultry production chain in the state, that currently meets with all requirements imposed. It is concluded that the State of Mato Grosso do Sul needs time for the poultry industry consolidation, and that therefore, is necessary the encouragement and attraction of new companies to strengthen the activity of broilers production in Mato Grosso do Sul.

Multi-Attribute Evaluation and Selection of Broiler House for the Low Prevalence of Footpad Lesion

Intensive broiler production requires large flock density, which compromises litter quality and increases the prevalence of footpad lesions. The present study aimed at comparing the incidence of footpad dermatitis of broilers reared in two different rearing environments. Data from two broiler houses were recorded during 42 d. Air temperature and relative humidity; litter moisture, pH, and temperature; footpad surface temperature; and the incidence of footpad lesions was investigated. Litter quality was analyzed in a 2 x 4 factorial arrangement, with two house types (dark house or open-sided house) and four rearing phases (21, 28, 35, and 42 d of growth), with four replicates per treatment using 12 replicates. Four replicates were used for analyzing the air environment data. For the footpad lesion identification, a randomly factorial scheme of recording the surface temperature was built (2 x 2) using two houses, and the broiler sex using 15 replicates in the grow-out stages. The measures of association (odds ratio and risk ratio) were calculated. The multi-criteria analysis (Analytic Hierarchy Process - AHP) was applied for estimating the house that provided less prevalence of lesions. The field data did not provide enough evidence for selection of a particular house with less incidence of footpad dermatitis. However, when applying the measures of association data, and corresponding literature data to the AHP, there was an indication that the dark-house provided broiler rearing condition that reduced the incidence of footpad lesions.(AU)

Evolução da produção e exportação de frangos de corte no estado do Mato Grosso do Sul / Brazilian State of Mato Grosso do Sul broilers production and exports evolution

O objetivo do trabalho foi realizar um panorama evolutivo da cadeia de produção e exportação de frangos de corte no estado do Mato Grosso do Sul considerando o período de 2007 à 2016. Posteriormente se fez uma comparação dos resultados com os encontrados no estado do Paraná e um levantamento das barreiras comercias impostas à importação da carne de frango do Mato Grosso do Sul. A pesquisa se trata de uma análise descritiva e foram utilizados dados do InfoAgro, Secretária do Estado de Meio Ambiente, Desenvolvimento Econômico, Produção e Agricultura Familiar, Estatística de Comércio Exterior do Agronegócio Brasileiro e Associação Brasileira de Proteína Animal. Os resultados apontam que o setor encontra-se em evolução dentro do Mato Grosso do Sul, com crescimentos significativos na produção e exportação. O Paraná possui um crescimento superior ao do Mato Grosso do Sul no período avaliado, o que evidencia o potencial de crescimento do estado. Verificou-se que as barreiras à importação da carne de frango comerciais impostas ao Mato Grosso do Sul não influem significantemente no crescimento da cadeia avícola no estado, e que atualmente o mesmo atende a todas as exigências. Conclui-se que o estado do Mato Grosso do Sul necessita de tempo para que ocorra a consolidação da avicultura, e que para tanto se faz necessário incentivo do governo para atração de novas empresas e fortalecimento da atividade junto aos produtores do estado.(AU)

The aim of this work was to bring out an evolutionary panorama of the broilers production and export in the Mato Grosso do Sul state, considering the period between 2007 and 2016. Subsequently a survey was made for the commercial barriers imposed on the importation of Mato Grosso do Sul broiler meat. The research is a descriptive analysis and data from InfoAgro, Famasul System and Agrostat and the Brazilian Association of Animal Proteins. The results indicate that the sector is in evolution within the Mato Grosso do Sul, with significant increases in production and exports. Paraná has a higher growth than Mato Grosso do Sul in this evaluated period, which shows the growth potential of the state. It has also been found that the barriers to the importation of commercial broiler meat, imposed on the MS do not influence significantly the growth of the poultry production chain in the state, that currently meets with all requirements imposed. It is concluded that the State of Mato Grosso do Sul needs time for the poultry industry consolidation, and that therefore, is necessary the encouragement and attraction of new companies to strengthen the activity of broilers production in Mato Grosso do Sul.(AU)

Factors Affecting Broiler Production: A Meta-Analysis

The meta-analysis data were obtained from a survey of published articles over 15 years. The data were selected to classify the factors that impact broiler production and separated by influence aspects of animal production (thermal environment and other factors). The relevant data for each study were systematized, grouped and later tabulated and inserted into a database prepared in a spreadsheet. The variables used to analyze the thermal environment were temperature (comfort, high and low) and performance data (weight gain, feed intake, and feed conversion). The variables used for other features were ventilation (TER = tunnel + evaporative cooling, PP = positive pressure, NV = natural ventilation) and performance (feed conversion, live weight, mortality, and weight gain). The factors that may influence the production of broilers were tested by covariance analysis, Pearson correlation coefficient and divergence analysis, about the Cobb®, Ross® and Hubbard® strains. The results showed that the factors that most influenced the performance of broilers were temperature, ventilation rate, and genetic strain.(AU)

Multi-Attribute Evaluation and Selection of Broiler House for the Low Prevalence of Footpad Lesion

Intensive broiler production requires large flock density, which compromises litter quality and increases the prevalence of footpad lesions. The present study aimed at comparing the incidence of footpad dermatitis of broilers reared in two different rearing environments. Data from two broiler houses were recorded during 42 d. Air temperature and relative humidity; litter moisture, pH, and temperature; footpad surface temperature; and the incidence of footpad lesions was investigated. Litter quality was analyzed in a 2 x 4 factorial arrangement, with two house types (dark house or open-sided house) and four rearing phases (21, 28, 35, and 42 d of growth), with four replicates per treatment using 12 replicates. Four replicates were used for analyzing the air environment data. For the footpad lesion identification, a randomly factorial scheme of recording the surface temperature was built (2 x 2) using two houses, and the broiler sex using 15 replicates in the grow-out stages. The measures of association (odds ratio and risk ratio) were calculated. The multi-criteria analysis (Analytic Hierarchy Process - AHP) was applied for estimating the house that provided less prevalence of lesions. The field data did not provide enough evidence for selection of a particular house with less incidence of footpad dermatitis. However, when applying the measures of association data, and corresponding literature data to the AHP, there was an indication that the dark-house provided broiler rearing condition that reduced the incidence of footpad lesions.

Factors Affecting Broiler Production: A Meta-Analysis

The meta-analysis data were obtained from a survey of published articles over 15 years. The data were selected to classify the factors that impact broiler production and separated by influence aspects of animal production (thermal environment and other factors). The relevant data for each study were systematized, grouped and later tabulated and inserted into a database prepared in a spreadsheet. The variables used to analyze the thermal environment were temperature (comfort, high and low) and performance data (weight gain, feed intake, and feed conversion). The variables used for other features were ventilation (TER = tunnel + evaporative cooling, PP = positive pressure, NV = natural ventilation) and performance (feed conversion, live weight, mortality, and weight gain). The factors that may influence the production of broilers were tested by covariance analysis, Pearson correlation coefficient and divergence analysis, about the Cobb®, Ross® and Hubbard® strains. The results showed that the factors that most influenced the performance of broilers were temperature, ventilation rate, and genetic strain.

Factors that Influence the Production, Environment, and Welfare of Broiler Chicken: A Systematic Review

The objective of the present study was to characterize the scientific production regarding the factors that influence broiler chicken production, and that were published from 2000 to 2015 in journals indexed in the database of Google Scholar, Scielo, and ScienceDirect. The research was done in the Thermal Comfort Laboratory at FEAGRI- UNICAMP, and the concept of the systematic review was applied. The research criterion was initially defined (the keywords) aiming to identify and evaluate the variables that describe the experimental characteristics and the animals. The primary keywords identified were: broiler chicken from commercial strains, broiler production, rearing conditions, thermal environment, air quality, acoustic environment, light intensity, management, and heat stress. Those were the key words searched in the database of the online libraries. The selected articles were registered into an electronic spreadsheet with the title, the name of the authors, year of publication, language, the journal where it was published, the keyword, the period when the research was done, source/ database, and the abstract. A total of 167 articles were selected, and only 34 were added to the review. The use of the systematic review of the literature allowed identifying the main variables that positively influence the broiler performance, such as the temperature near the thermal comfort, the use of roof lining, besides the use of adiabatic cooling and cast bricks in the laterals. The presence of positive ventilation, as well as the use of yellow curtains and constant lighting, has also influenced a better performance to broilers.(AU)

Factors that Influence the Production, Environment, and Welfare of Broiler Chicken: A Systematic Review

The objective of the present study was to characterize the scientific production regarding the factors that influence broiler chicken production, and that were published from 2000 to 2015 in journals indexed in the database of Google Scholar, Scielo, and ScienceDirect. The research was done in the Thermal Comfort Laboratory at FEAGRI- UNICAMP, and the concept of the systematic review was applied. The research criterion was initially defined (the keywords) aiming to identify and evaluate the variables that describe the experimental characteristics and the animals. The primary keywords identified were: broiler chicken from commercial strains, broiler production, rearing conditions, thermal environment, air quality, acoustic environment, light intensity, management, and heat stress. Those were the key words searched in the database of the online libraries. The selected articles were registered into an electronic spreadsheet with the title, the name of the authors, year of publication, language, the journal where it was published, the keyword, the period when the research was done, source/ database, and the abstract. A total of 167 articles were selected, and only 34 were added to the review. The use of the systematic review of the literature allowed identifying the main variables that positively influence the broiler performance, such as the temperature near the thermal comfort, the use of roof lining, besides the use of adiabatic cooling and cast bricks in the laterals. The presence of positive ventilation, as well as the use of yellow curtains and constant lighting, has also influenced a better performance to broilers.

Lipid profile of immunocastrated, castrated male and female pigs / Perfil lipídico de suínos machos castrados e imunocastrados e fêmeas

A presente pesquisa foi realizada com o objetivo de avaliar os níveis de colesterol, extrato etéreo, perfil de ácidos graxos e o índice aterogênico e trombogênico da gordura intramuscular de suínos machos imunocastrados em relação às fêmeas e aos machos castrados cirurgicamente. Utilizaram-se 45 animais, com peso inicial de 25,2±2,8kg, distribuídos em delineamento inteiramente ao acaso, com três tratamentos (machos castrados, machos e fêmeas imunocastrados) e três repetições de cinco animais cada. Os animais foram abatidos a 90,3±2,7kg. As amostras de Longissimus dorsi foram coletadas, liofilizadas e analisadas quanto ao perfil de ácidos gordos, colesterol e extrato etéreo. Não foram observadas diferenças (P>0,05) para nenhuma das variáveis analisadas entre a gordura intramuscular de machos castrados cirurgicamente, machos imunocastrados e fêmeas. A imunocastração não alterou os níveis intramusculares de extrato etéreo, colesterol, composição de ácidos graxos ou o índice aterogênico e trombogênico do Longissimus dorsi.(AU)

Lipid profile of immunocastrated, castrated male and female pigs / Perfil lipídico de suínos machos castrados e imunocastrados e fêmeas

A presente pesquisa foi realizada com o objetivo de avaliar os níveis de colesterol, extrato etéreo, perfil de ácidos graxos e o índice aterogênico e trombogênico da gordura intramuscular de suínos machos imunocastrados em relação às fêmeas e aos machos castrados cirurgicamente. Utilizaram-se 45 animais, com peso inicial de 25,2±2,8kg, distribuídos em delineamento inteiramente ao acaso, com três tratamentos (machos castrados, machos e fêmeas imunocastrados) e três repetições de cinco animais cada. Os animais foram abatidos a 90,3±2,7kg. As amostras de Longissimus dorsi foram coletadas, liofilizadas e analisadas quanto ao perfil de ácidos gordos, colesterol e extrato etéreo. Não foram observadas diferenças (P>0,05) para nenhuma das variáveis analisadas entre a gordura intramuscular de machos castrados cirurgicamente, machos imunocastrados e fêmeas. A imunocastração não alterou os níveis intramusculares de extrato etéreo, colesterol, composição de ácidos graxos ou o índice aterogênico e trombogênico do Longissimus dorsi.(AU)

Grape (Vitis vinifera) pomace flour as pigment agent of quail eggs

The aim of the study was to evaluate the effect of dietary grape pomace flour (GPF) inclusion on the performance and egg quality of European quails (Coturnix coturnix coturnix) in lay. One hundred ninety-two (192), 42-day-old quails were distributed in a completely randomized design with four treatments (0, 2, 4 and 6% grape pomace flour inclusion) with six replicates of eight birds each. The performance parameters egg weight (g), average feed intake (g/bird), total feed intake (g/bird), egg production (%) and feed conversion ratio (kg/dozen) were evaluated, as well as egg quality traits Haugh unit, albumen weight (g), yolk weight (g), eggshell thickness (mm), egg specific gravity (g/cm3), and yolk pigmentation. There was no effect (p>0.05) of dietary GPF levels on egg production, feed intake, or feed conversion ratio. Egg weight, albumen weight, and egg specific gravity linearly decreased (p<0.05) as GPM levels increased in the diet. Haugh unit and eggshell thickness were not affected (p>0.05) by the treatments. A quadratic effect (p<0.05) was observed for yolk weight, with an estimated maximal inclusion level of grape pomace flour of 4.18% to obtain the highest yolk weight. A quadratic effect (p<0.05) was also observed on yolk pigmentation, with an estimated minimal level of 3.2% for this parameter. The minimal inclusion of 3.2% of grape pomace flour in quail diets influenced the egg yolk pigmentation, demonstrating its efficiency as a pigmentation additive.(AU)

Grape (Vitis vinifera) pomace flour as pigment agent of quail eggs

The aim of the study was to evaluate the effect of dietary grape pomace flour (GPF) inclusion on the performance and egg quality of European quails (Coturnix coturnix coturnix) in lay. One hundred ninety-two (192), 42-day-old quails were distributed in a completely randomized design with four treatments (0, 2, 4 and 6% grape pomace flour inclusion) with six replicates of eight birds each. The performance parameters egg weight (g), average feed intake (g/bird), total feed intake (g/bird), egg production (%) and feed conversion ratio (kg/dozen) were evaluated, as well as egg quality traits Haugh unit, albumen weight (g), yolk weight (g), eggshell thickness (mm), egg specific gravity (g/cm3), and yolk pigmentation. There was no effect (p>0.05) of dietary GPF levels on egg production, feed intake, or feed conversion ratio. Egg weight, albumen weight, and egg specific gravity linearly decreased (p0.05) by the treatments. A quadratic effect (p<0.05) was observed for yolk weight, with an estimated maximal inclusion level of grape pomace flour of 4.18% to obtain the highest yolk weight. A quadratic effect (p<0.05) was also observed on yolk pigmentation, with an estimated minimal level of 3.2% for this parameter. The minimal inclusion of 3.2% of grape pomace flour in quail diets influenced the egg yolk pigmentation, demonstrating its efficiency as a pigmentation additive.

Incidence of Pododermatitis in Broiler Reared under Two Types of Environment

Housing environment is essential to achieve good broiler performance and to prevent diseases, including footpad dermatitis (FPD). The objective of this study was to determine the incidence of footpad dermatitis in broilers chickens according to housing type. The study was carried out with broilers reared for 5, 12, 19, 29 and 40 days. Four houses were used in this observational study. House 1 (A1) had positive pressure and reused litter; house 2 (A2) had positive pressure and new litter (sawdust); house 3 (A3) had positive pressure and new litter (rice husks); and house 4 (A4) had negative pressure and reused litter. During the entire experiment, air environmental and litter surface temperatures, and litter compaction were recorded. Pododermatitis was assessed by visual scoring of the footpads. Footpads were scored as function of the severity of the lesion. The comparison of means by the test of Bonferroni at 95% confidence interval showed higher incidence of footpad dermatitis in A3, probably due to the particle size of litter substrate. The lowest footpad dermatitis incidence was found in A1, with reused sawdust litter.

Incidence of Pododermatitis in Broiler Reared under Two Types of Environment

Housing environment is essential to achieve good broiler performance and to prevent diseases, including footpad dermatitis (FPD). The objective of this study was to determine the incidence of footpad dermatitis in broilers chickens according to housing type. The study was carried out with broilers reared for 5, 12, 19, 29 and 40 days. Four houses were used in this observational study. House 1 (A1) had positive pressure and reused litter; house 2 (A2) had positive pressure and new litter (sawdust); house 3 (A3) had positive pressure and new litter (rice husks); and house 4 (A4) had negative pressure and reused litter. During the entire experiment, air environmental and litter surface temperatures, and litter compaction were recorded. Pododermatitis was assessed by visual scoring of the footpads. Footpads were scored as function of the severity of the lesion. The comparison of means by the test of Bonferroni at 95% confidence interval showed higher incidence of footpad dermatitis in A3, probably due to the particle size of litter substrate. The lowest footpad dermatitis incidence was found in A1, with reused sawdust litter. (AU)

Risk of incidence of hock burn and pododermatitis in broilers reared under commercial conditions

The most common lesions observed in commercial broiler farms are hock burns and pododermatitis, defined as necrotic lesions on the plantar surface of the footpads and in the hock of growing broilers, causing pain and compromising broiler welfare. The present study aimed at identifying the risks of hock burns and pododermatitis in broilers reared under commercial conditions on new or reused litter. Twenty-four 40-d-old broilers reared in two houses in a commercial broiler farm. The plantar surface of the footpads and the hocks of broiler were recorded using infrared thermal images. The incidence of hock burns in broilers reared on new litter was 0.72 times lower than those on reused litter. Broilers reared on new litter presented lower risk (0.75, RR < 1) of presenting pododermatitis when compared to those reared on reused litter. When simulating the risk using a larger sample, the simulated risk of broilers presenting footpad and hock lesions when reared on new litter was 38% higher those reared on reused litter.

Effect of led lighting colors for laying Japanese quails

Time of exposure and light intensity rearing house may affect the performance and egg quality of laying quails. This research aimed at evaluating the live performance, egg quality, biometry of the reproductive system, and the gastrointestinal tract of Japanese quails (Coturnix coturnix japonica) exposed to artificial light-emitting diodes (LED) of different colors in comparison with fluorescent lamps. A total of 240 Japanese quails were distributed in completely randomized experimental design with four treatments (fluorescent lamp, and green, red, or blue LED lamps) with six replicates of 10 birds each. Average egg weight and eggshell thickness were different (p 0.05). The oviduct of 64-d-old hens exposed to green LED lighting was shorter (p < 0.05) than those exposed to the fluorescent lamp. Red LED can be used to replace the fluorescent lamps, as they promote the same live performance, egg quality, and morphological development of the reproductive tract of laying Japanese quails.

Effect of embryo thermal stimulation on the serum levels of immunoglobulins and corticosterone, and organ histopathology of 1 day-old broilers

Embryo thermal stimulation has been studied as a means to promote epigenetic changes and to improve broiler health and performance. This study aimed at evaluating immunoglobulin (IgM, IgG, and IgA) titers, serum corticosterone levels, and organ integrity of day-old male Cobb(r) and Ross(r) broilers. Embryos were submitted to hot and cold stimuli (thermal stimulation) on days 14-18 of incubation. The thermal manipulation treatments did not affect immunoglobulin titers of 1 day-old Cobb(r) or Ross(r) chicks, and caused severe bursal lesions (scores 3 and 4) in both strains. However, serum corticosterone levels of Cobb(r) chicks were higher when embryos were submitted to hot stimulus (+1.39ºC) compared with cold stimulus (+36 ºC). Serum corticosterone levels of Ross(r) chicks were not affected by embryo temperature manipulation. The only effect of broiler breeder age was observed on IgM titers of Cobb(r) chicks, which were higher in chicks from 33-wk-old breeders. Further studies are needed to detect the optimal period of embryo thermal stimulation.