Mônica Calixto Ribeiro de Holanda

Evaluation of minimal ventilation and animal performance of broiler chickens in poultry houses during winter

The objective of this work was to evaluate a system of minimal or hygienic ventilation and its influence on thermal comfort, air quality and broiler zootechnical performance of poultries raised during the winter. Two similar sheds were used, with 9,500 Cobb broiler chickens per shed, during a complete productive cycle. In one of the sheds, a positive ventilation system that met minimal need of air renovation, composed by three fans with flow of 300 m3/min, was installed on the ceiling parallel to the floor. The other shed was considered control and did not have a ventilation system. For the first two weeks of age of the broilers, temperature and air relative humidity differed, and the system with minimal ventilation showed the worst comfort conditions. Broilers kept in no ventilation system showed the best results for slaughter weight (with ventilation - 1.549; with no ventilation - 1.577 kg), food conversion (with ventilation - 1.63 kg/kg and with no ventilation - 1.59 kg/kg) and productive efficiency (with ventilation - 285 and without ventilation - 297). There were some differences for concentration of contaminant gases, which were lower in the system with minimal ventilation. The system with minimum ventilation, the way it was designed in the experiment, significantly decreases the temperature inside the poultry shed, compromising the thermal comfort and damaging animal performance. Although the system with minimum ventilation results in lower gas concentrations, none of systems promotes average concentration of carbon dioxide and carbon monoxide harmful to birds.The objective of this work was to evaluate a system of minimal or hygienic ventilation and its influence on thermal comfort, air quality and broiler zootechnical performance of poultries raised during the winter. Two similar sheds were used, with 9,500 Cobb broiler chickens per shed, during a complete productive cycle. In one of the sheds, a positive ventilation system that met minimal need of air renovation, composed by three fans with flow of 300 m3/min, was installed on the ceiling parallel to the floor. The other shed was considered control and did not have a ventilation system. For the first two weeks of age of the broilers, temperature and air relative humidity differed, and the system with minimal ventilation showed the worst comfort conditions. Broilers kept in no ventilation system showed the best results for slaughter weight (with ventilation 1.549; with no ventilation 1.577 kg), food conversion (with ventilation 1.63 kg/kg and with no ventilation 1.59 kg/kg) and productive efficiency (with ventilation 285 and without ventilation 297). There were some differences for concentration of contaminant gases, which were lower in the system with minimal ventilation. The system with minimum ventilation, the way it was designed in the experiment, significantly decreases the temperature inside the poultry shed, compromising the thermal comfort and damaging animal performance. Although the system with minimum ventilation results in lower gas concentrations, none of systems promotes average concentration of carbon dioxide and carbon monoxide harmful to birds.

Modelos de predição da natimortalidade em suínos

A total of 335 records of swine litters from 102 Large White females that farrowed between 1985 and 1996, born in the seasons of september to february and march to august, in the Recife city, in Pernambuco state (Brazil), were analysed. The objective was to compare regression equations to predict stillborn rates. Angular transformation (TA), a generalized linear model (GLM) with binomial distribution and logit link (BL), a Poisson GLM with log link (PL), a mixed GLM (GLMM) with binomial distribution and logit link (BLM) and a Poisson GLMM with log link were compared. Were considered the following sources of variation: average weight of piglets at birth in kilograms (P), age of the mother at birth in years (I), number of males (M) and females (F) born. Selection criteria for best model were prediction capacity and residual analysis. The best model was the GLM with binomial distribution with logit link with de variables age of the mother, number of males, and number of females.

Desempenho de frangos caipiras alimentados com farelo integral de mandioca

This study aimed to evaluate the performance and carcass characteristics of rednecks chickens fed diets containing the cassava root meal in increasing levels of inclusion of 12, 24, 36 and 48%. 360 chicks male, lineage Label Rouge were used, with eight days old, in a completely randomized design with five treatments and six replications of 12 birds each. The birds were fed isocaloric and isonitrogenous from eight to 84 days. Was evaluated feed intake, weight gain and feed conversion. Were killed two birds per cage with 5% ± standard deviation of the mean weight of the cage for evaluation of carcass yield and retail cuts, wings, breast, drumstick, thigh, back, abdominal fat and edible offal (liver, heart and gizzard). Data were subjected to analysis of variance and regression at 5 % probability using the computer program SAS (2001). Concluded that there was a linear increase in weight gain of birds and feed intake with increasing levels of inclusion of the cassava root meal, can be used up to 48% in the diet without prejudice to animal performance.

Rendimento de Carcaças de Frangos Caipiras Alimentados com Farelo de Algodão em Substituição à Proteína do Farelo de Soja

Objetivou-se avaliar o rendimento de carcacas de frangos caipiras alimentados com dietas contendo farelo de algodao em substituicao a proteina do farelo de soja. Foram alojadas 200 aves da linhagem Label Rouge, machos, distribuidos em um delineamento inteiramente casualizado com cinco tratamentos e cinco repeticoes com oito aves por parcela, totalizando 25 unidades experimentais. Os tratamentos constaram de uma dieta referencia a base de milho e farelo de soja e de quatro dietas teste (25, 50, 75 e 100%). A analise de regressao apresentou significância para as variaveis: peso da carcaca, peito, coxa, sobrecoxa, asas, dorso e gordura abdominal. As mesmas apresentaram comportamento quadratico quando o nivel de substituicao dos ingredientes da dieta avaliados atingiram os niveis otimos de 38,42; 32,46; 36,50; 35,35; 25,34 e 36,44%. A substituicao da proteina do farelo de soja pela proteina do farelo de algodao em dietas para frango caipira pode ser realizada ate o nivel de 38% sem afetar o rendimento de carcaca dos animais. DOI: 10.15528/2176-4158/rcpa.v14n1p65-68