提高绵羊产羔率及缩短其繁殖周期的技术

根据国内外有关提高绵羊繁殖率的大量研究结果，阐述并总结了提高绵羊排卵率与缩短其繁殖周期的综合措施及关键技术，采用外源激素（孕激素类或降黑素）诱发发情，必须根据绵羊的品种及和了节确定孕马血清促性腺激素（ＰＭＳＧ）的剂量才能获得理想的排卵率，在遗传改良上，以排卵率和睾丸大小为选择性状可民认加快产羔的遗传进展，根据社会生态条件入罗曼诺夫羊或芬兰羊杂交改良亦能有效地提高产羔率，在饲养管理上，加强饲养管理，

New Techniques for Increasing Lambing Rate and Manipulation of Oestrus in Sheep

New techniques for increasing lambing rate and manipulation of oestrus in sheep are expounded. When induced onstrus is considered in anoestrous season with progestagen or melatonin,it is emphasised that the dosage of PMSG varies with sheep breeds and the season. When genetic improvement for lambing rate is considered,it is suggested that prolificacy be more quickly improved if selection for both rams on test is size and ewes on ovulation rate,or crossing with highly prolific sheep breeds such as Finn and Romanov. The role of nutrition is evaluated and it is pointd out that a high nutrition level pre-mating ie. eight to five days before expected ovulation will increase ovulation rate and embryo survival. The role of immunological techniques in ovulation is also discussed in the paper.