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81.
The aim of this study was to evaluate the usefulness of trans-scrotal ultrasonography and testicular fine needle aspiration cytology in assessing bulls for breeding suitability. These two techniques were also compared with semen analysis. Bulls presented for breeding soundness evaluation were assessed using all three techniques. The findings of each technique were compared. There was agreement in classification of fertile bulls using all three techniques, suggesting that the combined use of these techniques enhances routine breeding soundness examination. Use of the three techniques also enhances detailed investigation of suspected sub-fertile bulls while accurately identifying testicular cause(s) of sire sub-fertility.  相似文献   
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Nutritional diarrhoea was induced in male Friesian calves by the addition of sucrose to their milk replacer diet in two experiments. In each study the calves were paired on the basis of the severity of the diarrhoea and each of a pair of calves was assigned at random to receive a course of six intramuscular injections (5 ml/50 kg body weight) of either a placebo or Buscopan compositum (morning and evening) over a period of 3 days. In an initial study, which involved 10 pairs of calves, daily faecal and urine output were collected separately for each calf on the day prior to the start of treatment and on each day of the 3 treatment days. The daily output of fresh faeces was reduced as a result of treatment with Buscopan compositum and the overall reduction for the complete 3 day period was 18.7%. This was also reflected in a reduced output of faecal water (18.4%) during the same period. The digestibility of the dry matter component of the diet was significantly increased by 5.8%.In a second experiment, which involved 24 pairs of calves, faecal samples were collected daily, commencing before initiation of treatment, for determination of faecal dry matter content. The pattern of change in the faecal dry matter content during the course of the study differed clearly for the two treatments. Faecal dry matter increased from its lowest level (11.7%), immediately prior to first treatment, to its maximum (21.8%) on the second day of treatment in the Buscopan compositum-treated calves. In the placebo-treated calves, however, the faecal dry matter content increased gradually until the end of the study, at which time it was still 9.8% lower than that of the Buscopan compositum-treated calves on the second day of treatment.The results of these studies show that Buscopan compositum has a useful role to play in the management of nutritionally induced calf scour.  相似文献   
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Sheep erythrocytes do not aggregate spontaneously but will sediment when mixed with a solution of hydroxyethylcellulose. The resulting leucocyte-rich supernatant can be used in the preparation of purified lymphocyte and granulocyte suspensions.  相似文献   
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