Marco Aurélio Neves da Silva

Avaliação dos comportamentos de aves poedeiras utilizando seqüência de imagens

The concern about the use of cages is related to barren environment and the minimal space offered to the laying hens, which negatively affects bird welfare. The present study focused on the aspect evaluation related to the behavior and welfare of birds, making a comparison between the alternative housing system (with litter and nests) and the conventional cage system. Two groups of 20 laying hens (10 Hy-Line W36 and 10 Hy-line Brown) at the beginning of the production were divided in two breeding systems (litter+nest and cages). Both of them were kept in climatic controlled chambers: one group with an ambient temperature of 26 °C and 60% RH (Thermal Comfort Condition) and the other in a temperature of 35 °C and 70% RH (Heat Thermal Stress Condition). A system of video cameras recorded the behavior of the laying hens. According to the behavior analysis, it was verified that the housing system on litter led to the expression of all natural behaviors related to bird comfort, which permitted to improve welfare conditions. In conventional system (laying cages) it was verified that birds tried to show their natural behavior in spite of lacking condition for it. This impossibility for expressing natural behaviors may have increased stress caused by the housing system and ambient condition.

Influência do sistema de criação sobre o desempenho, a condição fisiológica e o comportamento de linhagens de frangos para corte

The objectives of this research were to evaluate the influence of rearing systems (intensive or semi-intensive) on the performance (body weight and feed efficiency), chicken physiological condition under heat stress (rectal temperature, respiratory frequency and hematocrit) and behavioural parameters (frequency in the pasture areas) of broilers lines. To evaluate broilers performance and physiological condition on the ages of 45, 55, 65 and 75 days one experiment was carried out in boxes with 4,5 m2 of inside area and 35 m2 of outside area were 35 broilers were reared in each box. Another experiment was carried out to evaluate the frequency of broilers it the pasture areas from 35 to 75 days of age. One of the evaluated lines did not show adaptation to the semi-intensive rearing system. Significant differences were found in broilers performance and physiological conditions in both systems. In the semi-intensive rearing system the rectal temperature, respiratory frequency, hematocrit and feed efficiency were smaller and body weight larger than in the intensive rearing system. It was concluded that the semi-intensive rearing system provided conditions that increased broilers welfare and positively influenced the physiological conditions and performance of the broilers.

Avaliação do estresse térmico em condição simulada de transporte de frangos de corte

This experiment aimed to simulate thermal-stress-environment conditions in climatic chamber during the transportation of birds to slaughterhouse to evaluate the influence of these conditions on physiological parameters and carcass conformation in broiler chickens. Thirty chicks with 42 days old were weighted and distributed to transportation crates (10 chicks by crate), and submitted to high stress conditions (35oC and 85% RH) to simulate the transport to the slaughterhouse. At each time of exposition to the stress conditions (0, 30, 60, 90 and 120 minutes), two birds from each crate was withdrawn for further analyses. Body weight, rectal temperature, respiratory frequency and hematocrit value were measured, and after that they were slaughtered to evaluate of carcass conformation (carcass, breast, legs (thighs and drumsticks), back and viscera weights). Physiological and carcass conformation characteristics (body weight loss and legs weight, wings and back weights) differed after be submitted to high stress conditions. The exposition time and the environment conditions of transport affected negatively the metabolism and thermal body equilibrium of broilers.

Síndrome ascítica em frangos de corte: uma revisão sobre a fisiologia, avaliação e perspectivas

Poultry genetic breeding programs which look for maximum weight gain, improved feed conversion, high viability, high carcass yield and low fat deposition may cause some physiologic syndromes, for example caloric stress, sudden death and ascites. Ascites is framed in concept of the multifactorial syndromes, once its manifestation happens when certain genetic and environment factors act together, determining the process. Anatomical and physiological limitations in blood circulation in the lungs give rise to pulmonary hypertension syndrome (PHS), producing great fluid accumulation in abdominal cavity, which is denominated ascites. Ascites causes reduction of blood circulation efficiency, leading broilers to death due to hypoxia, mainly between 30 and 40 days of age. Ascitic broilers have reduced body weight gain as a consequence of feed restriction. Additionally, there is increased abdominal cavity volume and internal organ congestion. Ascites is discussed through this manuscript based on physiological description, evaluation measures and perspectives.

Avaliação de materiais genéticos visando à produção de frango caipira em diferentes sistemas de alimentação

The aim of the current study was to evaluate the performance of experimental and commercial genotypes of chicken recommended for free-range rearing system submitted to two diet programs (conventional and alternative). The experimental design consisted of a randomized design applied until 28 days and a randomized factorial 8x2 design (eight genotypes: Paraiso Pedres, Caipirao da ESALQ, 7 P, Embrapa 041, Label Rouge, Paraiso Pelado, Caipirinha da ESALQ and Carijo Barbada and two diet programs), using two replicates with 30 chickens/box as experimental unit, from 29 to 84 days of age. Average body weight and feed:gain ratio were recorded during three periods: 1) 0-28, 2) 0-56 and 3) 0-84 days and submitted to the analysis of variance. The effect of diet was evidenced for all traits in periods 2 and 3. The effect of genotype was verified for all variables in period 1, but only for average body weight in periods 2 and 3. The interaction genotype and diet was observed for feed:gain ratio in period 2 and for all traits in period 3. Paraiso Pedres and Caipirao from ESALQ presented higher average body weight than the other genotypes in period 1. In period 2, Paraiso Pedres presented the highest average body weight and all genotypes differed for feed:gain ratio. Caipirao from ESALQ, Paraiso Pedres and 7 P presented higher average body weight than the other genotypes and all strains differed for feed:gain ratio in period 3. The full substitution of conventional diet by corn led to a worse chicken performance. Overall performance of the evaluated genotypes was conditioned by genetic and nutrition factors, with the lowest negative effects of substitution of conventional diet by corn on all traits in the Paraiso Pedres genotype.

Influência do sistema de criação nos parâmetros comportamentais de duas linhagens de poedeiras submetidas a duas condições ambientais

RESUMO - Este estudo foi realizado com os objetivos de avaliar o comportamento e o bem-estar de aves em um sistema de criacao em cama e ninho, em comparacao a um sistema de criacao convencional (bateria de gaiolas), e estudar a influencia das condicoes ambientais (estresse e conforto) no comportamento de poedeiras. Dois grupos de dez aves (dez Hy-line W36 e dez Hy-line Brown) em inicio de postura foram submetidos a duas condicoes ambientais (26°C e 60% UR e 35°C e 70%UR) e dois sistemas de criacao (bateria de gaiolas e cama) durante duas semanas consecutivas. Durante o periodo de avaliacao, um sistema de câmeras de video instaladas no teto da câmara climatica registrava o comportamento das aves. Os parâmetros comportamentais foram avaliados durante 2 horas no periodo da manha e 2 horas no periodo da tarde, com gravacoes feitas a cada segundo. Para melhor avaliacao individual do comportamento, as aves foram marcadas com tinta atoxica. Pela analise do comportamento, verificou-se que o sistema de criacao em cama propiciou a expressao de todos os comportamentos naturais e de conforto das aves, fornecendo melhores condicoes de bem-estar. No sistema de criacao convencional (gaiolas), mesmo sem nenhuma condicao, as aves tentaram executar seus habitos naturais e, certamente, a impossibilidade de expressarem esses comportamentos agravou o estresse provocado por este sistema de criacao.

Fatores de estresse associados à criação de linhagens de avós de frangos de corte

The aim of this study was to evaluate the performance and the variability between parental lines of broiler chicken reared in different environments, considering the genotype and environment interaction. Performance and morphometric traits of parental lines of commercial broiler chicken reared up to the age of 42 days in a complete-controlled environment of a breeding farm, in usual conditions of broiler chicken production system and in stress environment conditions were evaluated. Indexes of thermal comfort (temperature and humidity and enthalpy) were used to evaluate the internal microclimate of the instalations, where the birds were reared. Comparison of averages of performance (body weight and carcass yield) and morphometric (back and leg featherings) traits of parental lines indicated they differed according to the rearing environment. Body weight and carcass yield were higher for male than for female lines, which presented better back and leg feathering than the male lineages.

Influence of The Genotype and Sex on The Hematocrit Value of Meat-Type Chicken

The objective of this research was to evaluate the effect of the genotype and sex on the value of meat-type chicken hematocrit (percentage packed cells volume). One hundred and eighty breeders of 18 experimental genotypes were used. Individual samples of blood were collected and the percentage packed cells volume was determined. For the factor genotype, it was possible to distinguish two different groups with averages changing from 45,83 to 41,69% and 41,24 to 37,21%. For sex, the values showed significant difference with values of 46,20 ± 4,14% for males and 35,74 ± 3,16% for females. In conclusion the genotype and sex influenced the hematocrit value in meat-type chickens, above to cluster every genotypes in two groups.

Avaliação do desempenho zootécnico de genótipos de frangos de corte utilizando-se a análise de medidas repetidas

Objetivou-se avaliar genotipos de frangos de corte por meio do desempenho zootecnico utilizando-se medidas repetidas. Os tratamentos consistiram de quatro genotipos (A, B, C e D) e dois sexos avaliados em seis idades (7, 14, 21, 28, 35 e 42 dias). As variaveis analisadas foram: consumo medio de alimento (CONS), peso vivo medio (PV) e conversao alimentar (CA). O delineamento experimental foi em blocos incompletos desbalanceados, em esquema fatorial 4x2 nas parcelas experimentais, com seis medidas realizadas no decorrer do experimento. A analise estatistica foi realizada por meio do procedimento MIXED do SAS®, sendo testadas cinco estruturas de variância e covariância do erro. As medias foram estimadas por quadrados minimos e comparadas pelo teste Tukey-Kramer. Foram estimadas funcoes de resposta quadratica para CONS e CA e Gompertz para PV e seus respectivos coeficientes de determinacao, pelo procedimento NLIN do SAS®. Detectaram-se efeitos de algumas interacoes triplas ou duplas para todas as variaveis. Verificaram-se diferencas significativas entre genotipos dentro de cada idade e sexo para CONS e PV e para CA entre genotipos e sexos, dentro de cada idade, apenas aos 42 e a partir dos 21 dias, respectivamente. Constatou-se que o genotipo D, apesar de apresentar maiores medias de CONS e PV, nao mostrou menor CA, que foi verificada nos genotipos C e B. As funcoes de resposta estimadas explicaram adequadamente cada variavel em funcao da idade, constatando-se que o CONS e PV dos machos do genotipo D foram maiores a partir dos 14 dias e dos 28 aos 42 dias, distinguindo este tratamento dos demais. A melhor CA foi verificada nos machos e no genotipo C. E possivel avaliar o desempenho zootecnico de frangos de corte por medidas repetidas, sendo que os genotipos B e C apresentaram melhor desempenho zootecnico.

Welfare Evaluation by Image Analysis of Laying Hens in Different Breeding Systems and Environmental Conditions

This work aimed to evaluate aspects related to behavior and welfare of hens, comparing a conventional housing system (battery cages) with another system using litter, lair and roost. In addition, the effects of environmental conditions (stress or comfort) on final egg quality and behavior responses (analyzed by precision techniques) were evaluated using two laying hen lines. Two groups of 20 birds (10 Hy-line W36 and 10 Hy-line Brown) at the beginning of the production phase were submitted to two environmental conditions (26°C with 60% RH or 35°C with 70% RH) and two housing systems (battery cages or litter) during two consecutive weeks. During the evaluation period, bird behaviors were recorded by video cameras. Eggs produced during the whole experimental period were analyzed according to these quality parameters: egg weight, shell thickness, specific gravidity and Haugh unit. A significant (P<0.05) reduction in quality parameters was observed in eggs from laying hens raised under heat stress, mainly in those from the cage system. In relation to behavior, the housing system in litters proportioned the expression of all natural behaviors and those related to bird comfort, which permitted to improve welfare conditions. In the conventional system (laying cages), birds tried to manifest their natural behaviors in spite of lacking conditions for it. This impossibility for executing natural behaviors certainly promoted an increase of stress originated by this kind of housing system.