乏情母犬用溴隐亭处理后的发情表现与血清中孕酮和雌二醇水平变化

选择 3只年龄为 3岁处于乏情期的苏北红犬和 6只 1～ 2岁未发情的罗威纳犬 ,用溴隐亭处理后有 4只母犬发情 ,1只母犬受孕而后流产。分析犬血清中雌二醇和孕酮水平 ,发情受孕犬雌二醇和孕酮分泌呈现规律性变化趋势 ;发情未受孕犬在雌二醇分泌峰出现后孕酮分泌不稳定 ;而未发情犬雌二醇和孕酮没有变化。结果表明 ,溴隐亭能够有效地缩短母犬的乏情期 ,溴隐亭处理后不同生理状态母犬反应差异较大 ,发过情的母犬作用明显 ,对从未发过情的母犬效果较差     

Changes in plasma melanocyte-stimulating hormone,ACTH, prolactin,GH, LH,FSH, and thyroid-stimulating hormone in response to injection of sulpiride,thyrotropin-releasing hormone,or vehicle in insulin-sensitive and -insensitive mares

Six insulin-sensitive and 6 insulin-insensitive mares were used in a replicated 3 by 3 Latin square design to determine the pituitary hormonal responses (compared with vehicle) to sulpiride and thyrotropin-releasing hormone (TRH), 2 compounds commonly used to diagnose pituitary pars intermedia dysfunction (PPID) in horses. Mares were classified as insulin sensitive or insensitive by their previous glucose responses to direct injection of human recombinant insulin. Treatment days were February 25, 2012, and March 10 and 24, 2012. Treatments were sulpiride (racemic mixture, 0.01 mg/kg BW), TRH (0.002 mg/kg BW), and vehicle (saline, 0.01 mL/kg BW) administered intravenously. Blood samples were collected via jugular catheters at −10, 0, 5, 10, 20, 30, 45, 60, 90, and 120 min relative to treatment injection. Plasma ACTH concentrations were variable and were not affected by treatment or insulin sensitivity category. Plasma melanocyte-stimulating hormone (MSH) concentrations responded (P < 0.01) to both sulpiride and TRH injection and were greater (P < 0.05) in insulin-insensitive mares than in sensitive mares. Plasma prolactin concentrations responded (P < 0.01) to both sulpiride and TRH injection, and the response was greater (P < 0.05) for sulpiride; no effect of insulin sensitivity was observed. Plasma thyroid-stimulating hormone (TSH) concentrations responded (P < 0.01) to TRH injection only and were higher (P < 0.05) in insulin-sensitive mares in almost all time periods. Plasma LH and FSH concentrations varied with time (P < 0.05), particularly in the first week of the experiment, but were not affected by treatment or insulin sensitivity category. Plasma GH concentrations were affected (P < 0.05) only by day of treatment. The greater MSH responses to sulpiride and TRH in insulin-insensitive mares were similar to, but not as exaggerated as, those observed by others for PPID horses. In addition, the reduced TSH concentrations in insulin-insensitive mares are consistent with our previous observation of elevated plasma triiodothyronine concentrations in hyperleptinemic horses (later shown to be insulin insensitive as well).