羔羊供应属季节性性质,主要解释为绵羊繁殖的季节性性质,但产品需求全全年存在。 为了满足市场需求,进口产品和养羊家用绵羊延长供应季节可满足供应缺量。 在北美一些地区,持有绵羊有损产品质量,因为绵羊进入市场往往过度肥成熟。 填补供应缺量并避免产品质量顾虑的另一个策略是通过淡季羊肉生产实现的。淡季生产允许全年捕捉最成熟的绵羊,当结合产区间下降时,加速生产被称为加速生产,加速生产有可能提高生产效率并同时消除季节性供应造成的约束

加速生产或季节外生产的其他模式要成功,就必须想方设法克服季节性对绵羊繁殖的限制。幸运的是,有些品种季节性较弱,选择从季节性生长。然而,这些品种大都仍然表现出一定的季节性性性能并显示较低受孕和排卵率,介于不最优半冬至中夏育值周期中。 利用相对淡季遗传基值,管理这些种群可以提高不使用外生激素的不最优育季的生殖效果

季节性较强绵羊增肥可通过以下方式实现:

• 改善公羊和母牛的营养管理
• 改善育种管理实践
• 筛选雄性生育
• 增强雄性生物刺激,常称它为公牛效果

拉姆效果

视觉、嗅觉和行为提示对ewes可产生模拟效果一些人称此段为
非肥季与肥季之间的过渡效果常用称号为 Up效果浅度退产环境包括高度季节性种即将进出境典型退产周期(2月至7月北半球不育期)并在整个Aestruce周期内来自小季节性种

ewes从公羊分离至少30天后最强效果。ewes长段分离雄鸟时,雄鸟重引入或诱导行为演程17天后全循环,或引起ewes在接触4-6天后展示“静态”热量,ewe先播送但不显示行为演程。17天后行为演程继之以静热产生2种行为变换方式群中:一到17,一到23天群暴露后。由于变换时间和绵羊变容长度微小变化,人们看到集中产期约7天公关效果允许进取和同步estrus 。 多数制作者喜欢进取效果,但有些人不愿同步ewes,因为它集中放羊期到可以对设施或人工资源课税的程度。 减轻这一效果的一个选择可能是将ewe群分成二分制并错开并周向每个组群介绍肥马

最典型的分解公牛(非肥羊常被称为“牛羊 ” ) 用来产生这种效果。公羊表现出正常交配行为,但却无法成功浸泡少数显示行为变迁的ewes,导致肥公公羊更好地同步育种We are learning that most ewes, including those thought to be relatively aseasonal, stop cycling mid-winter to mid-summer and go into a light anestrus that can be rescued by ram introduction.  If teaser rams are not used, and fertile rams are simply turned in during this period, the ram effect is still at play.  It simply manifests in the majority of ewes settling on the second heat cycle following the fertile ram exposure.  If teaser rams are used, the process is "jump started" a cycle, with most ewes lambing during the first cycle following fertile ram exposure.  We do not know if the use of teasers rams necessarily improves ovulation rate or conception rate over that observed using fertile rams that settle ewes in the second cycle following exposure.  Some feel that use of teaser rams "spares" the serving capacity of fertile rams, since the fertile rams are not actively chasing as many ewes over an extended period to detect estrus, thereby conserving energy and improving conception rates.  What we do know is that the ram effect is a major factor in natural mating during what is considered the out-of-season period, it synchronizes mating, and is able to jump start breeding.

推荐滑板覆盖为2-3%,公羊介绍14天前引入计划肥马

筛排肥

Rams should be screened for fertility prior to any breeding season to reduce risk of breeding failure.  This becomes relatively more important during out-of-season mating.  The minimal screening method is to palpate the ram's testicles to record their firmness and to detect the potential presence of inflammation or scar tissue.  Fertile ram testes are firm and never soft, nor are they hard to the touch.  The presence of a distinct epididymis should also be present at both the head and tail of the testes.  Careful palpation screening can remove about 65-75% of infertile rams, but identification of the remaining 25-35% of subfertile/infertile rams requires a breeding soundness exam.  This procedure requires collection of semen, typically via electric ejaculation, and semen examination for gross semen motility, functional morphology and indications of male reproductive tract infection.  Rams with more than 80% normal semen morphology and strong waves of gross motility are the ones needed for the more challenging out-of-season breeding period.

保证大坝肥力

提高雄性生育能力的另一个方法就是接触光线协议。 照片周期操作证明提高公羊和ewe生育能力However, the feasibility of placing the entire ewe flock under photoperiod control is less practical than applying control to a smaller population of rams.  A light protocol that has been shown to improve ram fertility is a 120-day cycle consisting of: 30 days of 16h light/8h dark, followed by 30 days of 8h light/16h dark, followed by 30 days of 16h light/8h dark, followed by final round of 30 days of 8h light/16h dark followed by introduction of rams to ewes.  Rams maintained under this protocol for 4 months appear to maintain a high state of fertility thereafter for the breeding season.

拉姆覆盖

拉姆覆盖度推荐高于季节外播种期。这可产生更大的生物模拟效果(射线效果)。3-5%覆盖推荐无estros同步或4-8%与estrus同步方法并不清楚群交配机制中公羊竞赛的动态是否对羊群概念有益或有害。 人可以推理子肥但活性雄性的负面影响在群养法中会最小化bob体育登录增强竞争最终是否有害或改善生殖结果?

牛群营养管理

Well-fed, fine-wool rams have enhanced fertility over those fed a maintenance diet during the out-of-season period.  Therefore, it is recommended to increase the plane of ram nutrition to 2 times their maintenance energy intake for the 4-week period prior to mating so that rams are certain to reach a target condition score of 3.5 at mating.  It is also recommended to group rams according to nutritional needs during this period, with rams under 2 years, and especially those under 12 months, grouped separately from mature rams.  The working model to explain the beneficial impact of nutrition on male fertility during the out-of-season period is that the signals that enhance testosterone production and semen quality are amplified when rams are in positive energy balance (gaining weight) and able to overcome the negative signals present that lower fertility during the out-of-season period.

ees营养管理

BOB体育密歇根州立大学启动了一系列研究,以优化ewe营养提高加速生产中的生殖效果,其主要目的是提高总体生殖效果,特别是在淡季阶段。这项工作是在加速编程中完成的,该编程使用自然交配系统而不使用外生荷尔蒙理疗程。到目前为止,我们已经学到冲洗ewes提供二倍维护能摄取量

在此期间,我们还研究了喂养不足ewes对50%维护的影响,但有趣的是,我们没有看到营养不足对生育结果的影响,相对向百分之百维护能源需求提供ewes而言。这告诉我们补充进增量和权重增量(阳性能源平衡)对任何播种季节优化生殖结果都非常重要,但在淡季期间尤其如此。我们现在扩展这些研究以研究ewe营养在冲洗期前(回溯前哺乳期)对加速生产中牛群生产率的若干方面的影响。

简言之,我们强烈推荐在加速生产交配前3周向ewes提供优食。我们已经评估了收入比fece成本的变化,在加速生产前3周向ewes提供优食前3周使用2018年10月美国密歇根市市场模拟模型。分析显示收入比fe

相对季节性绵羊的生殖效果可以提高,通过筛选公羊肥力并增强雄性生物刺激效果(ram)

选择引用 :

卡梅隆J马尔波B和卡通夸F2010年通过图片周期定序加速放羊,全年交替四月长短日应用,《动物科学杂志》88:3280-90

Chemineau P, Malpoux B, Delgadillo J, Guerin Y, Ravault J, Thimoneier J和Pelletier J.1992 控制绵羊和山羊复制:使用光和melatonin.动物生殖科学30:157-184

Ehrhardt R开发管理策略改善绵羊季节性复制bob体育合法吗可持续农业研究教育报告http://mysare.sare.org/mySARE/ProjectReport.aspx?do=viewRept&pn=FNE05-544&y=2006&t=0

ForcadaF和AbeciaJ-A2006年 营养对Ewes复制的适配性复制、营养开发 46:355-265

hottzelM公司、Wakden-BrownS公司、FisherJ公司和MartinG公司成熟男性梅里诺和苏福克绵羊年度复制模式的决定因素:对育种和非育种季节神经刺激的反应。再生、生育与发展15:1-9

KarschFBittmanE RobinsonJYLONSWayneNOLSTERDKYNLERDA1986.Melatonin和相容性:对melatonin信号的反射

Menassol J-B、ColletA、ChesneauD、MalpouxB和ScaramuzziR.2012图片周期和营养之间的交互作用 及其对季节性节奏的影响 ewe复制生物86:52:1

ungerfedR、ForsbergM和RubianesE.2004年无名雌马响应概述