Protein and energy for maintenance and gain of European quail fed different energy sources and housed at two temperatures

The objective of this study was to evaluate whether replacing corn starch (CS) energy with isolated soy protein (ISP) and soybean oil (SO) and the ambient temperature affect the protein and energy requirements for maintenance and gain of European quail. Thus, a total of 432 European quail from 10 to 30 days of age, distributed in a completely randomized design, were used to estimate the protein and energy requirements for maintenance through the comparative slaughter methodology. The treatments consisted of three diets formulated with the replacement of CS, corresponding to 15% of the metabolizable energy in the diet, with ISP and SO, two controlled temperatures (26 and 35 °C), and three levels of feed supply (ad libitum, and 70 and 40% of ad libitum intake), with four replicates of six birds. Protein and energy requirements for weight gain were determined from 160 European quail, slaughtered every five days at 10, 15, 20, 25, and 30 days of age. Birds were housed in four groups of 40 birds in a room with thermoneutral temperature (26 °C). The energy sources of the feed and temperatures studied affected protein and energy requirements for maintenance and gain of European quail. Replacing CS energy by 15% of dietary energy with SO results in lower protein and energy maintenance requirements for European quail at both temperatures. The protein and energy weight gain requirements of quail fed SO as an energy source is higher than CS and ISP.(AU)

Physiological variables and egg quality from quails (Coturnix coturnix japonica) that received water with increasing levels of NaCl and under different temperatures / Variáveis fisiológicas e qualidade de ovos de codorna (Coturnix coturnix japonica) que receberam água com teores crescentes de NaCl e sob diferentes temperaturas

The objective of this study was to evaluate the influence of water salinity and ambient temperature on the physiological variables and the quality of Japanese quail eggs (Coturnix coturnix japonica) in the laying phase. The quails received water with increasing levels of salinity (1.5, 3.0, 4.5 and 6.0 dS m-1) and were kept in climatic chambers under two different temperatures (24ºC and 32ºC). The design used was completely randomised, with a 2 x 4 factorial arrangement (temperatures and salinity levels), with six replicates of eight birds each. Data were submitted for analysis of variance and the means were compared by the Tukey test at 5%. There was no influence (P > 0.05) of water salinity levels on the physiological variables nor on the quality of the birds' eggs. At 32oC there was an increase (P < 0.05) in respiratory rate, cloacal and body surface temperature of the birds, and a slight reduction (P < 0.05) in the weight of eggs, shells, and percentage of shell. For laying quails, water with salinity levels of up to 6.0 dSm-1 can be used and the birds can be raised in an environment with temperatures up to 32ºC.(AU)

O objetivo do trabalho foi avaliar a influência da salinidade da água e da temperatura ambiente nas variáveis fisiológicas e na qualidade dos ovos de codornas japonesas (Coturnix coturnix japonica) na fase de postura, recebendo água com níveis crescentes de salinidade (1,5, 3,0 , 4,5 e 6,0 dS m-1), e mantidos em câmaras climáticas sob duas temperaturas diferentes (24 e 32ºC). O delineamento utilizado foi inteiramente casualizado, com arranjo fatorial 2x4 (temperaturas e níveis de salinidade), com seis repetições de oito aves cada. Os dados foram submetidos à análise de variância e as médias comparadas pelo teste de Tukey a 5%. Não houve influência (P > 0,05) dos níveis de salinidade da água nas variáveis fisiológicas e na qualidade dos ovos das aves. A 32ºC houve um aumento (P < 0,05) na frequência respiratória, temperatura cloacal e da superfície corporal das aves e uma pequena redução (P < 0,05) no peso dos ovos, cascas e porcentagem da casca. Para codornas em postura pode-se utilizar água com salinidade de até 6,0 dSm-1, podendo as aves ser criadas em ambiente com temperatura de até 32ºC.(AU)

Effects of different proteases on commercial laying hens at peak production

We evaluated the effect of adding proteases in diets of laying hens at peak production on the performance, egg quality, relative weight of digestive organs, and intestinal morphometry. Hy-Line W36 layer hens (390; 28-39 weeks old) were distributed in five treatments, with 13 animals each, with six replicates. The treatments were: control (standard formulation without nutritional reduction or protease inclusion), negative control A - NCA (nutritional reduction according to protease A matrix, without protease), negative control B - NCB (nutritional reduction according to protease B matrix, without protease), NCA + protease A, and NCB + protease B. The experimental period lasted 12 weeks, divided into three cycles of 28 days. Hens subjected to treatments (NCA and NCB) showed a decrease in feed intake. However, the addition of proteases A and B promoted improvement in this trait. The diets NCA and NCB had a negative influence on the production rate of the hens, but the diet supplementation with protease B resulted in significant improvement on egg laying rate. Hens subjected to nutritional reduction presented the worst results regarding mass and conversion by egg mass. However, the addition of enzymes reversed these results. Although the diets did not affect the relative weights of yolk, albumen, eggshell, Haugh unit, and specific gravity of the eggs, a higher eggshell thickness was observed in hens that received NCA, NCB, and NCB + protease B diets. The diets did not influence the relative weights of digestive organs and the small intestine morphometry. Hens fed diets supplemented with A and B have performance recovered in relation to those that received diets with reduced levels of nutrients.(AU)

Mathematical models to describe the growth curves of white-egg layers / Modelos matemáticos para descrever curvas de crescimento de poedeiras leves

The aim of this study was to compare mathematical models describing growth curves of white-egg layers at different population densities. To fit the models, 4,000 growing white-egg layers were utilized. The experimental design was completely randomized, with population densities of 71, 68, 65, 62, and 59 birds per cage in the starter phase and 19, 17, 15, 13, and 11 birds per cage in the grower phase, with 10 replicates each. Birds were weighed weekly to determine the average body weight and the weight gain. Gompertz and Logistic models were utilized to estimate their growth. The data analysis was carried out using the PROC NLMIXED procedure of the SAS® statistical computer software to estimate the parameters of the equation because mixed models were employed. The mean squared error, the coefficient of determination, and Akaikes information criterion were used to evaluate the quality of fit of the models. The studied models converged for the description of the growth of the birds at the different densities studied, showing that they were appropriate for estimating the growth of white-egg layers housed at different population densities. The Gompertz model showed a better fit than the Logistic model.(AU)

Esta pesquisa teve por objetivo comparar modelos matemáticos para descrever curva de crescimento de poedeiras leves em diferentes densidades populacional, por meio de equações de modelos de crescimento.Para o ajuste dos modelos foram utilizadas 4000 poedeiras leves em crescimento. O delineamento utilizado foi o inteiramente casualizado nas densidades populacional de 71, 68, 65, 62 e 59 aves por gaiola na fase de cria e de 19, 17, 15, 13 e 11 aves por gaiola na fase de recria, com dez repetições cada.Semanalmente, as aves foram pesadas para determinação do peso corporal médio e o ganho de peso. Para estimar o crescimento das aves foram utilizados os modelos de Gompertz e Logistic. A análise dos dados foi realizada pelo procedimento PROC NLMIXED do programa computacional estatísticoSAS®, para estimar os parâmetros da equação por se tratar de modelos mistos. O quadrático médio do erro, o coeficiente de determinação e o critério de informação de Akaike foram utilizados na avaliação da qualidade do ajuste dos modelos. Os modelos estudados atingiram a convergência para a descrição do crescimento das aves nas diferentes densidades estudadas, adequados para estimar o crescimento corporal das aves com alto grau de confiabilidade. Os modelos estimaram o crescimento de poedeiras leves, alojadas em diferentes densidades populacional, em que o modelo de Gompertz apresentou melhores ajustes em comparação ao Logistic.(AU)

Mathematical models to describe the growth curves of white-egg layers / Modelos matemáticos para descrever curvas de crescimento de poedeiras leves

The aim of this study was to compare mathematical models describing growth curves of white-egg layers at different population densities. To fit the models, 4,000 growing white-egg layers were utilized. The experimental design was completely randomized, with population densities of 71, 68, 65, 62, and 59 birds per cage in the starter phase and 19, 17, 15, 13, and 11 birds per cage in the grower phase, with 10 replicates each. Birds were weighed weekly to determine the average body weight and the weight gain. Gompertz and Logistic models were utilized to estimate their growth. The data analysis was carried out using the PROC NLMIXED procedure of the SAS® statistical computer software to estimate the parameters of the equation because mixed models were employed. The mean squared error, the coefficient of determination, and Akaikes information criterion were used to evaluate the quality of fit of the models. The studied models converged for the description of the growth of the birds at the different densities studied, showing that they were appropriate for estimating the growth of white-egg layers housed at different population densities. The Gompertz model showed a better fit than the Logistic model.

Esta pesquisa teve por objetivo comparar modelos matemáticos para descrever curva de crescimento de poedeiras leves em diferentes densidades populacional, por meio de equações de modelos de crescimento.Para o ajuste dos modelos foram utilizadas 4000 poedeiras leves em crescimento. O delineamento utilizado foi o inteiramente casualizado nas densidades populacional de 71, 68, 65, 62 e 59 aves por gaiola na fase de cria e de 19, 17, 15, 13 e 11 aves por gaiola na fase de recria, com dez repetições cada.Semanalmente, as aves foram pesadas para determinação do peso corporal médio e o ganho de peso. Para estimar o crescimento das aves foram utilizados os modelos de Gompertz e Logistic. A análise dos dados foi realizada pelo procedimento PROC NLMIXED do programa computacional estatísticoSAS®, para estimar os parâmetros da equação por se tratar de modelos mistos. O quadrático médio do erro, o coeficiente de determinação e o critério de informação de Akaike foram utilizados na avaliação da qualidade do ajuste dos modelos. Os modelos estudados atingiram a convergência para a descrição do crescimento das aves nas diferentes densidades estudadas, adequados para estimar o crescimento corporal das aves com alto grau de confiabilidade. Os modelos estimaram o crescimento de poedeiras leves, alojadas em diferentes densidades populacional, em que o modelo de Gompertz apresentou melhores ajustes em comparação ao Logistic.