【摘要】 选用24头空怀考力代母羊作试验,以激素处理,6头考力代怀孕后期母羊作对照。第8天起每日挤乳两次,测定乳量、比重并分析主要成分。放免测定对照羊分娩前后和试验母羊处理前后血浆中雌二醇（E₂）和孕酮（P）的浓度,同时还测定羔羊的生长速度。 结果表明,Ⅰ、Ⅱ组泌乳量显著高于Ⅲ、Ⅳ组（P<0.01）,并有半数母羊平均泌乳量超过300m¹,加注催乳素可使泌乳量较快上升,但与单独注射地塞来松（D）的母羊间无显著差异（P>0.05）。可的松对泌乳量无影响。处理期间血浆E₂和P的浓度与投药量呈正相关。但血浆E₂和P的投药比例相差甚远。乳产量与处理后血浆E₂的浓度呈负相关（r=-0.56）。诱导乳外观似常乳,除乳脂偏高、乳蛋白略低外,乳糖、干物质和比重与常乳相近。诱导泌乳母羊哺育孪生羔羊与亲母羊哺育的一头孪生羔羊体重间无显著差异（P>0.01）。更多还原

【Abstract】 Group Ⅰ and Ⅱ （6 ewes in each） were daily injected subcutanously with 25 mg estradiol-17 β （E₂）and 70 mg progesterone （P）for seven days; group Ⅲ and Ⅳ （6 in each） with 12.5 mg E₂ and 70 mg （P） for 14 and 7 days. At the 14th day, the ewes in group Ⅰand Ⅲ were injected intramuscutary with 20 mg dexaraethasone （D） and those in group Ⅱ and Ⅳ with 20 mg D and 20 mg prolactin. At the 18th day, half of the ewes in each group were injected intravenously with 100 mg cortisol and another half with 10 ml physiological saline solution. Ewes were milked twice daily from the 8th day, milk yields were recorded and sampled weekly for measuring specific gravity, total solid, fat, lactose and protein content. The concentration of E₂ and P in blood plasma collected 20 days before to 9 days after parturition, and 8 days before to 30 days after the beginning of hormonal treatment were mensured by RIA.The growth of lambs was investigated. Mean milk yield in group Ⅰ and Ⅱ was significantly higher than that in group Ⅲ and Ⅳ （P<0.01） , half of the ewes in group Ⅰ and Ⅲ produced over 300 ml milk daily. The milk yield of ewes injected with D and prolactin was higher than that of ewes injected with D alone, but there was no significant difference between them （P>0.05）. Injection of contisol had no effect on milk yield. The concentrations of plasma E₂ and P during hormonal treatment were positively correlated with the dosages, but the ratio between the two hormones in vivo differed significantly from that in vitro. The milk yield correlated negatively with the concentration of plasma E₂ after the end of hormonal treatment （r=-0.56）. There was no significant difference between body weights of the single twin lambs fostered by ewes induced lactation and the twin lambs nursed by their own mothers.更多还原