Abstract: 【Objective】 To study the influence of melatonin on Duolang sheep pregnancy and lambing effect, to select the optimal amount to improve the pregnancy rate and lambing rate and improve the reproduction rate. 【Method】This study selected 57 Duolang sheep ewes with similar age, parity and body condition from November 2016 to April 2017 to conduct experiments in the professional farmers' cooperatives in Luopu County of Hotan area. Sheep were randomly divided into three groups at the same time for the same period of estrus, and after the withdrawal of 36 hours, the test group I was injected melatonin 1 mL (5 mg), the test group II 2 mL (10 mg), the control group 0ml. And before the burying bolt (12 o'clock midday), bolt withdrawal (12 o'clock midday), 36 hours after the bolt withdrawal (12 o'clock midnight), the breeding (48 hours after embolization, serum withdrawal) of the five time periods for 20 days after the acquisition of its breeding, melatonin contents were determined and analyzed by radioimmunoassay; forty-fifth days after mating, they went through B-monitoring assay in three groups' pregnancy for the lambing rate; After the birth, the lambing rate of the three groups was compared.【Result】The test results showed that the pregnancy rate of test group I was significantly higher than that of the test group II and the control group (P < 0.05), there was no significant difference between test group II and control group (P > 0.05); As for the the lambing rate, comparison between the three groups demonstrated no significant difference (P > 0.05).【Conclusion】When treating Duolang sheep estrus, subcutaneous injection of 1 mL, 2 mL melatonin 36 hours after the withdrawal of thrombus can improve the pregnancy rate. The pregnancy rate of 1 mL injection amount is higher than that of 2 mL injection, but no significant effect is found on the lambing rate.

Key words: melatonin; Duolang sheep; pregnancy effect; lambing

摘要： 【目的】研究褪黑素对多浪羊受胎及产羔效果的影响,提高多浪羊繁殖率。【方法】研究注射褪黑素提高受胎率和产羔率的方法,选择年龄、胎次、体况相似的57只多浪羊母羊,试验羊随机分为三组同时进行同期发情处理,并在撤栓36 h后皮下注射褪黑素注射剂。试验1组1 mL (5 mg)、试验2组2 mL (10 mg) 、对照组0 mL。并在埋栓前(中午12:00)、撤栓时(中午12:00)、撤栓后36 h(晚上24:00)、配种时(撤栓后48 h,中午12:00)、配种后20 d五个时间段采集血清,采用放射免疫法对其褪黑素含量进行测定与分析;配种后第45 d采用B超监测法检测三组的受胎率;在产羔后比较这三组的产羔率。【结果】试验1组受胎率显著高于试验2组和对照组(P＜0.05),试验2组与对照组之间差异不显著(P＞0.05);对产羔率而言,三组之间相互比较后无统计学差异(P＞0.05)。【结论】对多浪羊进行同期发情处理时,撤栓后36 h皮下注射1、2 mL褪黑素会提高受胎率,其中1 mL的受胎率高于2 mL ,但是对产羔率无显著影响。

关键词: 褪黑素, 多浪羊, 受胎效果, 产羔