Influências da salinidade da água e temperatura do ar na produção de ovos de codornas japonesas.

Abstract

Water quality is a critical success factor for good animal performance, and birds consuming two to three times more water than feed, and in the semiarid region the demand for water for consumption is high, which favors practice of small activities, due to the lower water consumption. The objective of this study was to evaluate the influence of water salinity and air temperature on performance, egg quality, physiological parameters and organ morphometry of Japanese quails in the production phase. The research was developed in two climatic chambers with automatic temperature and relative humidity control, located in the experimental area of the Laboratory of Rural Constructions and Ambience of the Academic Unit of Agricultural Engineering, Federal University of Campina Grande. A total of 394 Japanese quails were distributed in a completely randomized design in a 2x4 factorial arrangement, with two temperatures (24 and 32ºC) and four salinity levels (1.5, 3.0, 4.5 and 6.0 dS/m), totaling eight treatments with six replicates and eight birds per experimental unit. The experimental period was 84 days divided into four periods of 21 days. At the end of each experimental period, the productive performance of the birds was evaluated: feed intake (g/bird/day), water consumption (ml/bird/day), egg production (%), egg weight (g), egg mass (g), and feed conversion (kg/kg and kg/dozen), egg quality: weight and percentage of yolk, albumen and bark, specific gravity (g/ml) and the physiological parameters: respiratory rate (FR), cloacal temperature (TC) and body surface temperature (TSC). At the end of the experimental period, two birds per plot were slaughtered, totaling 96 birds, which were submitted to fasting of solids for twelve hours, then sacrificed, plucked, eviscerated and subjected to individual weighing and weighing of organs: heart, liver and gizzard. The data were submitted to analysis of variance, having significant difference the averages were compared by the test of Tukey to 5%. Salinity levels did not affect productive performance, egg quality, physiological variables and body weight, except for bark thickness and gizzard weight, which presented a linear effect as salinity levels increased. The ambient temperature affected the performance and egg quality variables, with higher values for the animals kept at 32 oC. The respiratory rate, cloacal temperature and body surface temperature were higher at the higher temperature, but remained within the average considered normal for the species. The weight of the gizzard was affected by the stress temperature and by the higher salinity level, where the weight of the gizzard was higher. Japanese quails in the production phase can consume water with salinity levels up to 6.0 dS/m without having the productive performance, egg quality, physiological parameters and morphometry of their affected organs and be created in an environment with temperatures of up to 32ºC for a daily period of 12 hours, since even the temperature affected some of the studied parameters, the quail kept the homeothermy.