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The literature mostly indicates that docking fat-tailed lambs initially reduces growth but that post-weaning growth and feed conversion efficiency then increase. The amount of fat deposited, the total separable lean meat to fat ratio and the meat quality all increase, while the percentage of bone in the carcase either decreases or does not change in the carcases of the docked lambs. Wool growth and characteristics are, in general, not affected and reproductive traits in ewes and lambs are improved by docking. The rectal temperature, respiration rate and pulse rate are decreased following docking. The concentrations of immunoreactive beta-endorphin and cortisol in the plasma and the incidence of foot stamping and restlessness, as indicators of stress, increase after docking. Other constituents of the blood are not significantly altered following docking or by the methods of docking. Docking of fat-tailed sheep using rubber rings at one day of age can be recommended. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
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Twenty each of healthy lactating Friesian and Holstein cows were studied. They were of similar age and body weight, nonpregnant in their third lactation and 80–100 days post partum. The investigation was carried out for 8 weeks on two farms at the same time during the hot summer season in Egypt. The first farm was in Demietta (North east of the Nile Delta, 31° 40 N) on 20 Friesian cows and the second was in Fakous (East of the Nile Delta, 30° 40 N) on 20 Holstein cows. On each of the two farms, 10 cows were newly imported and 10 were born in Egypt.The average daily milk yield and total milk production in the third lactation of the newly imported cows were significantly higher than those of the locally born cows for both Friesians and Holsteins. At the same time, the T4, T3, urea-N, haematological values and AST enzyme activity in the newly imported cows were significantly lower than those in the locally born ones in both breeds, while the locally born cows showed significantly lower values for rectal temperature and respiration rate, as well as for AST and Alk-P enzyme activities, than the newly imported cows of either breed.Holstein cows surpassed the Friesians in milk production, as well as thyroid hormone secretion and cholesterol, haemoglobin, packed cell volume and erythrocyte count values. The opposite was found for serum total protein, urea-N and creatinine concentrations, leukocyte count and AST, ALT and Alk-P enzyme activities.  相似文献   
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Growth rate and efficiency of food conversion of Landes and Italian goslings, from hatching to 8 weeks of age, were measured. The goslings were fed on a starting ration containing 19.5% crude protein and 2877 kcal/kg (11.8 MJ/kg) for the first 3 weeks of age and then a growing ration containing 17.5% crude protein and 2877 kcal/kg (11.8 MJ/kg).

The mean body weight was similar in both breeds at 1 d of age, while at 8 weeks the Italian breed was slightly heavier than the Landes. The weekly percentage weight gain for the two breeds were similar, however.

The efficiency of food conversion was higher in the first 4 weeks than in the second 4 weeks in both breeds. The daily food consumption and the efficiency of food conversion of the Italian goslings were lower than those of the Landes throughout the period of the study.  相似文献   

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This review discusses the historical, developmental and practices of ostrich farming in Egypt. In the early 20th century, ostrich farming was very important for production of ostrich feathers and documents were produced to perfect the art of procuring the plumes from the birds and subsequently processing them. Pharaohs used ostrich feathers for adornment. Of 43 provinces, 12 were featured in 2003-2004 as farming ostriches: Alexandria, Al-Behera, Al-Dakahlia, Al-Wadi Al-Gadid, Aswan, Cairo, El-Sharkia, Geiza, Ismailia, Kafr-El-Sheikh, Matrouh and Nubaria. Abattoirs and tanneries specialising in ostrich handling are limited to two. Egypt has numerous strengths and opportunities to develop its ostrich sector. Rising meat prices suggest that fresh ostrich meat is unaffordable to many locals. Funds may be allocated to local advertising campaigns to promote ostrich meat; provision of incentives to farmers; and improving the capacity of abattoirs.  相似文献   
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The somatotrophic and thyrotrophic cells were originally developed in the adenohypophysis from undifferentiated chromophobic cells at the foetal age of 4-8 weeks. The follicle-stimulating hormone cells appeared at a foetal age of 24-28 weeks. Prolactin and luteinizing hormone cells were first seen at of foetal age levels of 32-36 and 40 weeks. The germinal epithelium of flattened and cuboidal cells in the ovary was changed to cubical and columnar types, 24-28 weeks of foetal age. The sex cords appeared at 8-12 weeks of foetal age. The primary and secondary follicles were observed at 8-12 and 20-24 weeks of foetal age, respectively. Follicular cavity was noticed at 32-36 weeks, while large follicles encapsulated by follicular sheath were seen in the 40th week of foetal age. Some ovarian follicles degenerated during or after their development. Surface epithelium in the uterus changed from cubical to columnar type at 8-12 weeks of foetal age. The endometrium was clearly distinguished from the myometrium at 16-20 weeks of foetal age. The uterine glands appeared at 16-20 weeks as short and straight tubular glands, and they began to branch in the 40th week of foetal age.  相似文献   
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Exposing growing and adult New Zealand White (NZW) female rabbits to severe heat stress (temperature–humidity index = 28.9) during summer adversely affected their growth and reproductive traits. The traits that declined significantly (p<0.01) were the live body weight, daily weight gain and feed intake of growing rabbits, and the litter size and litter weight at weaning (p<0.05) and the pre-weaning weight gain of pups (p<0.01) for adult females. The conception rate declined considerably with heat stress. The declines in the values of the digestibility coefficients due to heat stress were 7.9% (p<0.05) for dry matter (DM), 8.1% (p<0.05) for crude protein (CP) and 1.0% for crude fibre (CF). The traits that increased significantly (p<0.01) due to heat stress were water intake, water/feed ratio and rectal temperature in growing rabbits and pre-weaning mortality for adult females.Alleviation of heat stress in the growing and adult female NZW rabbits was more efficient with drinking cool water (10–15°C; between 10:00 and 17:00) than with supplementation with palm oil (as a source of energy) or natural clay (as a natural enhancer to growth and milk production). Supplying the animals with cool drinking water gave the highest body weight and weight gain, conception rate, litter size and weight and digestibility coefficients for DM and CP and the lowest rectal temperature, respiration rate and pre-weaning mortality.The loss in rabbit production pertaining to heat stress estimated from the percentages of decline in conception rate×pre-weaning mortality×litter weight at weaning was 73.0%. The provision of cool water restored 11/12 of heat loss.  相似文献   
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Thickness of epidermis, diameter and density of follicles as well as the ratio of secondary to primary follicles went up with significance (P less than 0.01) along with development. Medium concentrations of neutral and acid mucopolysaccharides were histochemically recorded from the corium, while high levels were present in basal stratum and hair pivots. High concentrations of alkaline phosphatase were recorded from basal stratum, hair pivots, and papillae and moderate concentrations from sweat and sebaceous glands, with the latter containing also glycogen and lipids.  相似文献   
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Tolerance of New Zealand White (NZW) and Californian (Cal) doe rabbits at the first parity to the sub-tropical environmental conditions of Egypt was evaluated. The study included 1090 parturitions: 601 NZW and 489 Cal. The does used were 5 months of age and 3.1 ± 0.10 kg mean body weight. The study was carried out during the different seasons of the year. The results showed that the effects of breed on the traits studied were not significant except on the doe kindling weight. However, the traits studied were, in general, higher in NZW than in Cal. The estimated temperature–humidity index (THI) average values were 19.8, 18.0, 23.7 and 25.7 during autumn, winter, spring and summer, respectively, indicating absence of heat stress during autumn and winter (less than 22.2) and exposure to severe (more than 23.3) and very severe heat stress (more than 25.6), during spring and summer, respectively. The effects of season of kindling were highly significant (P < 0.001 or 0.01) on conception rate, gestation period, kindling weight, litter weight at birth (live and total), 21 days of age and at weaning and kit weight at birth. The values were, in general, the lowest (P < 0.05) during the very severe heat stress in summer, while the kindling interval and pre-weaning mortality were the highest in summer. Adaptability was estimated (during the four seasons of the year) to be 93.3% and 95.1% for NZW and Cal, respectively. No interactions were observed in the analysis.  相似文献   
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