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2. NKC was treated with sodium hydroxide at 10 (ANKC 1) or 20 g (ANKC 2)/kg and incorporated into the test diets at 135 or 300 g/kg to replace 50 (low—L) or 100 (High—H) % of the PNM protein of the reference diet.
3. Despite comparable retentions of dry matter and total carbohydrate on L‐ANKC 1 and 2, fibre on L‐and H‐ANKC 2 and nitrogen, calcium and acid detergent fibre on all experimental diets compared to the retentions of chicks on the reference diet, only the chicks fed L‐ANKG 2 were found to grow and utilise food as well as those on the reference diet.
4. The activities of serum alkaline phosphatase on H‐ANKC 1 and alanine amino transferase on all test diets were depressed (P < 0.05), but the activity of serum aspartate amino transferase, total erythrocyte count and concentration of blood haemoglobin and urea were similar in all chicks.
5. No significant differences were noticed in the qualitative and quantitative characteristics of the meat of chicks fed on the reference diet and on diets incorporating ANKC at the lower concentrations. Feeding ANKC protein did not impart any untoward taste as evaluated in pressure cooked meat by a semitrained panel on a 7 point Hedonic scale.
6. Except for duodenal and jejunal inflammation in chicks on both reference and test diets, all the vital organs were normal, ruling out any adverse affects caused by residual neem bitters.
7. Comparable performance and cost of chicks fed on the reference and L‐ANKC 2 diets, warrants the utilisation of hitherto wasted protein‐rich NKC after alkali treatment in broiler chick diets to spare peanut meal for human consumption in developing countries. 相似文献
2. Chicks from the two genotypes were reared in wire‐floored cages and divided at random into 3 groups. Birds were fed on high protein (HP, 12.99 MJ ME, 238 g crude protein/kg and 12.94 MJ ME, 216 g crude protein/kg from 0 to 3 and 3 to 7 weeks, respectively), medium protein (MP, 12.99 MJ ME, 219 g crude protein/kg and 12.87 MJ ME, 201 g crude protein/kg from 0 to 3 and 3 to 7 weeks), and low protein (LP, 12.94 MJ ME, 205 g crude protein/kg and 12.75 MJ ME, 184 g protein/kg from 0 to 3 and 3 to 7 weeks) diets.
3. The LP diets resulted in a significantly lower daily body weight gain of males from 0 to 3 weeks. Dietary protein content had no effect on body weight gain from 3 to 7 weeks, body weight at 7 weeks, and the food intake of birds. Carcase composition of birds from both genotypes was unaffected by dietary protein.
4. Naked neck birds had significandy higher body weights at 7 weeks. Yields of carcase and breast of Na/na males were significantly higher than those of na/na males. There were no significant differences between females from the two genotypes as regards carcase yield.
5. It was concluded that the dietary protein requirements of naked neck birds were similar to those for normally feathered birds. 相似文献