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971.
The course of a disease due to Salmonella pullorum in laying chickens is described. The experimental application of enrofloxacin (Baytril) at a dosage of 100 mg/l drinking water for 10 days resulted in a stop of the mortality rate, increment of egg production and reduction of Salmonella excretion. A recurrence of the disease was observed in the fifth week following the end of treatment with high mortality and decreasing egg laying. The treatment lead to a short-dated success but a permanent elimination of the germ from the flock was not achieved.  相似文献   
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Two experiments were performed on sheep, receiving on maintenance level a pelleted straw ration high in crude fibre (straw, 70.5%; dried sugar beet pulp, 12%; cereals, 10%; urea, 2%; ammonium hydrogen carbonate, 3%; minerals 2,5%). The animals were fitted with ileo-caecal re-entrant cannulas. The effects of the introduction of HC1-partly hydrolysed straw meal into the digesta of the large intestine on the digestion processes in that segment were studied. Under these conditions the metabolism of 14C and 15N labelled urea, which was given into the caecum, was estimated. In experiment 1 (E 1; 2 animals) unlabelled, precollected digesta were hourly reintroduced together with 14C and 15N labelled urea via the caecal cannula. In experiment 2 (E 2; 3 animals) the digesta were supplemented with partly hydrolysed straw meal (10% of the mean daily DM-intake with the ration). The supplement of partly hydrolysed straw meal caused an increase of the 15N excretion with faeces from 13.4% (E 1) to 19.8% (E 2) of the dose. The 15N was mainly incorporated in the bacterial fraction (98% E 1; 96% E 2). As a reason for the increased 15N incorporation into the bacterial fraction of 106.4 mg15N' in E 2 vs. 67.3 mg15N' in the experiment without straw meal supplement the higher supply of energy as fermentable carbohydrates was assumed.  相似文献   
974.
In an internordic field study of the effect of the Ca dose (6, 9 and 12 g) on the therapeutic result in parturient paresis, considerably better results were recorded in Finland than in the other countries at all dose levels. In Finland a full effect was obtained with 6 g, while in all others 9 g Ca yielded a significantly better result than 6 g. Raising of the dose to 12 g produced no improvement. There was a significant difference in therapeutic results between the two Finnish breeds. A larger number of fatal cases was recorded among paretic cows with plasma Ca greater then 8.0 mg/100 ml.  相似文献   
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