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2. Eggs incubated at 36.5°C hatched later than eggs incubated at 37.5°C but did not differ in age of mortality or incidence of malpositions and abnormalities.
3. Eggs incubated at 38.5°C hatched significantly less well than eggs incubated at 37.5°C and showed significant differences in time of embryo mortality. Overheated embryos had a mortality peak between 15 and 20 d of incubation and an increased mortality after 24 d of incubation.
4. Overheated eggs were characterised by a high incidence of embryos with head in small end, with excess albumen, ruptured yolk sacs, oedematous heads, eye cataracts and swollen down‐plumules. 相似文献
2. Broiler performance in terms of growth, food conversion ratio, carcase meat, fat and protein content was optimised on the 240 to 220 g/kg protein starter‐grower series of diets.
3. Birds of the slow line were significantly (P<0.05) heavier at 48 d of age and had the same food intake and food conversion ratio as birds of the fast feathering line.
4. The slow line birds had significantly (P<0.01) shorter feathers and less total plumage weight at 48 d. The slow line birds had significantly (P<0.001) less carcase fat and significantly (P<0.05) more carcase protein than the fast line. The slow line had significantly more carcase meat (P<0.01) within which a greater breast meat yield was evident (P<0.001). 相似文献
2. Body weight gain and food efficiency of chicks significantly increased with the supplement of dietary MCT compared with dietary LCT at all food intakes. Protein retention and the efficiency of protein utilisation (protein retained/protein intake) at all food intakes also significantly increased with dietary MCT, while body fat and fat retention were significantly reduced. Chicks fed the LCT‐supple‐mented diet, on the other hand, had a lower protein retention, but significantly higher fat retention. The value for energy retention and the efficiency of energy utilisation (energy retained/ME intake) were not significantly different between MCT‐ and LCT‐supplemented diets.
3. It was concluded that supplementing MCT to the chick diet would improve body weight gain and protein utilisation while regulating fat deposition compared to the LCT supplemented diet, under equalised feeding conditions. 相似文献
2. Initial mean body mass was similar for the two breeds: 1525 g for Bedouin hens and 1542 g for White Leghorn hens. White Leghorns lost 7–74 g/d, compared with 0.60 g/d for Bedouin hens and produced 0.36 eggs/d, compared with 0.54 eggs/day for Bedouin hens.
3. The heterophil/lymphocyte ratio for Bedouin hens was 0.28, which was lower than the 0.44 for White Leghorn hens. Phagocytic index was higher in Bedouin hens than in White Leghorns. Furthermore, wattle index measured 24, 48 and 72 h after PHA injections and anti‐SRBC antibody titres determined 10 d after challenge were also higher in Bedouin hens than in White Leghorns.
4. We concluded that the Bedouin hens were less stressed by the cold than were the White Leghorn hens. 相似文献
2. The growth of chickens on all diets were significantly (P<0.05) reduced.
3. Examining the weights of broiler organs as a proportion of body weight showed a significant (P<0.05) decrease in the weight of the liver and an increase in the weights of the kidney, brain and pancreas.
4. Serum urea concentrations were elevated (P<0.05) in all groups receiving base‐soluble protein (BSP), acid‐soluble protein (ASP), defatted jackbean (DJB) and raw jackbean (RJB) diets. Enzyme activities were similarly elevated (P<0.01), but serum protein and albumin concentrations were depressed while uric acid was not influenced by dietary treatment.
5. Histopathological examination revealed several pathological lesions in organs of chicks fed on the BSP, ASP, DJB and RJB diets. The presence of lesions was less marked in the organs of chickens fed on diets containing base‐insoluble residue (BIR), acid‐insoluble residue (AIR) and ethanol‐extracted meal (EEM), while those given the aqueous heated jackbean diet did not show any pathological effects. 相似文献
2. Daily water intake in the WARM hens (103 ml/kg) was similar to that of the CONR (93 ml/kg) and CONA hens (106 ml/kg).
3. There were no significant differences in either body mass change or egg production among treatment groups.
4. There was no difference among groups in heterophil/lymphocyte ratios. Similarly, there was no difference among groups in either phagocytic activity or wattle index after phytohaemagglutinin (PHA) injection. Total and IgG antibody titres to SRBC tended to be highest in the WARM hens and these titres were significantly higher than in CONR hens 14 d after challenge. 相似文献
2. Turkeys with lower weights between 13 and 30 d of age tended to have higher temperatures.
3. Turkeys with lower weights at 7 d exhibited depressed body temperatures.
4. Higher or lower body temperatures may be associated with poorer performance depending on the time of appearance. 相似文献