| Abstract: |
The main objectives of this work was to investigate the effect of stocking density (80 or 50 birds / m2 during growing period and 40 or 25 birds / m2 during laying period) and four levels of feed additives (without supplementation as control, 1.0 g / kg diet sodium bicarbonate, 1.2 g / kg diet ascorbic acid and 1.0 g sodium bicarbonate + 1.2 g ascorbic acid / kg diet) on performance and some physiological traits of growing and laying Japanese quails.Obtained results can be summarized as the following:1- Growing experimental:High stocking density (80 birds/m2) significantly decreased body weight, body weight gain, feed conversion ratio and pre-slaughter weight of growing Japanese quails at 6 weeks of age, while, wing temperature at 1-3 weeks of age, haemoglobin value, plasma levels of, cholesterol, ALT, AST and A/G ratio were significantly increased under high stocking density.All feed additives significantly increased body weight at 6 weeks of age and body weight gain at 1-3 weeks of age and significantly decreased plasma level of AST. Dietary supplementation of sodium bicarbonate caused a significant increase in feed intake at 1-3 weeks of age and haemoglobin value. Ascorbic acid supplementation significantly increased body weight at 2 weeks of age, body weight gain and feed intake at 1-3 weeks of age, plasma level of total protein and globulin and significantly decreased rectal temperature at 3-6 weeks of age and wing temperature at 1-3 and 3-6 weeks of age as well as plasma level of cholesterol, A/G ratio and ALT. Moreover, the combination between sodium bicarbonate and ascorbic acid significantly increased body weight at 3 weeks of age, body weight gain at 1-3 weeks of age, haemoglobin value, plasma level of total protein, albumin, globulin and significantly decreased rectal temperature at 3-6 weeks of age and wing temperature at 1-3 and 3-6 weeks of age as well as plasma level of cholesterol, ALT and A/G ratio.2- Laying experimental:High stocking density (40 birds/m2) significantly decreased egg number and egg mass, feed intake at 14-18 weeks of age and plasma level of ALT.All feed additives significantly increased egg number, egg mass, egg weight at 10-14 weeks of age as well as fertility and hatchability percentages and significantly decreased plasma level of cholesterol and ALT. Dietary supplementation of sodium bicarbonate caused a significant improved in feed conversion ratio and significant increase in plasma level of AST. Ascorbic acid supplementation significantly increased feed intake, egg weight, USSW at 14-18 weeks of age and significantly decreased rectal temperature. Furthermore, the combination between sodium bicarbonate and ascorbic acid significantly improved feed conversion ratio and significantly increased USSW at 14-18 weeks of age and significantly decreased plasma level of total protein, albumin and globulin.In conclusion, the results of this study indicated that, through the hot summer of Egypt, the best Japanese quail performance could be obtained by supplementing 1.0 g sodium bicarbonate/kg diet or 1.2 g ascorbic acid alone or in combination of the diets under low stocking density (50 and 25 birds/m2 during growing and laying period, respectively).
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