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991.
Replacement of the drinking water of chicks maintained on a normal mixed protein diet with an aqueous extract containing the equivalent of 5 g of the dried leaves of Solanum malacoxylon (DLSM) per 100 ml for one month produces a hypercalcaemia (23-49 per cent), hypomagnesamia (28-37 per cent), hypophosphataemia (26-34 per cent), hypouricaemia (29-34 per cent) and a decrease in plasma alkaline phosphatase activity (54-98 per cent). The ash content of the defatted, dried tibiae and the body weight of the DLSM treated chicks were also significantly lower (37-7 per cent and 17-79 per cent respectively) than the corresponding values for the untreated birds. The results obtained are similar to those reported for hypervitaminosis D3 in the chick. 相似文献
992.
Uterine motility was recorded for several weeks in 10 ovariectomised goats, using small intra-uterine balloons, to study the effects of female sex hormones on uterine activity and reactivity to oxytocin. Oestradiol stimulated uterine contractions and increased both the sensitivity and intra-uterine pressure response to oxytocin. When progesterone was administered in addition to oestradiol, spontaneous uterine motility became irregular with low amplitude contrations; the sensitivity and reactivity to oxytocin was significantly depressed. 相似文献
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1. Hens fed on a diet containing 0–05% calcium virtually ceased egg laying (production <4%) whereas those fed on a diet containing 0–5% Ca maintained production at between 20 and 30%.
2. After a return to a normal diet (3% Ca) egg weight, shell weight, ovarian characteristics and oviduct size were of a similar nature in the two groups, though the differences in egg weight, shell weight and shell calcium were significant at the 1 % level.
3. Bone weight and bone ash did not differ significantly between the groups but after a return to normal rations, bone weight and bone ash became higher in the group that had received the 0.05% Ca diet.
4. There were no clinical signs of bone demineralisation during the experiments. 相似文献
999.
A large-scale trial was carried out under commercial conditions to investigate to which extent the feeding of rations with varying lysine content to young hens would influence the crude nutrient content of the body fractions and might change the pattern of amino acid composition and the activity of GOT in the blood. Four rations were fed each containing 14.2% crude protein, 626-633 EFh units/kg and 0.59%, 0.61%, 0.54% and 0.46% lysine. The crude protein and crude fat content of the total body and of body fractions were in no case found to be related to the feeding regime. The proportion of crude ash in the "remainder of non-utilizable parts", in "bones", "intestinal and abdominal fat", "ovaries" and "small intestine" decreased with the decreasing lysine content of the rations. The concentrations of free lysine, histidine, arginine, and phenylalanine in the deproteinized blood plasma of the young hens were significantly (a = 0.01) lower in the birds of the lysine deficient group than in the hens of the other groups. Positive regressions were calculated for the lysine content or the content of aspartic acid in the ration and the pattern of free amino acids in blood plasma. Positive and negative linear relationships were found to exist between the concentrations of free lysine, and those of histidine, arginine or threonine, and serine. A close correlation existed between the total amount of essential amino acids in blood plasma and the lysine concentrations of the plasma. Increasing lysine supplementation produced a decline in the N content of the whole blood and blood corpuscles but a rise in the N content of blood plasma. The activity of GOT in the blood of young hens was not found to be useful as an indicator of the quality of dietary proteins. 相似文献
1000.
Lesions induced in each of 9 young colostrum-deprived calves closely resembled lesions seen in naturally occurring "weak calf syndrome" of eastern Idaho and southwestern Montana. The disease was experimentally induced by intravenous injection of bovine adenovirus type 5 that had been isolated from a calf with weak calf syndrome... 相似文献