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Improving dairy cattle reproduction through development of synchronization of ovulation protocols and economic decision support systems.

机译：通过开发排卵协议和经济决策支持系统来提高奶牛繁殖能力。

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摘要

A series of experiments were conducted to develop resynchronization of ovulation protocols to improve the fertility of timed artificial insemination services, assess the effect of circulating progesterone concentrations on LH secretion from the pituitary gland after GnRH treatment (Section I), and to evaluate the association between timing of embryonic demise and hormonal dynamics after induced pregnancy loss in lactating dairy cows (Section II). In addition, decision support systems to make economic based decisions at the time of selecting reproductive management programs for dairy herds were created based on simulation models (Section III). Results from three experiments in Section I showed that the use of presynchronization of the estrous cycle before the initiation of Resynch improved the fertility of resynchronized services in lactating dairy cows. Presynchronization was effective to improve fertility by increasing the percentage of cows with a functional corpus luteum at the initiation of Resynch and the percentage of cows responding to the protocol injections. Also, increased progesterone concentrations similar to those observed in cows with a functional corpus luteum at the time of GnRH treatment suppresses release of LH from the pituitary gland. This suppressive effect of progesterone on GnRH-induced LH release can be partially overcome by increasing the dose of GnRH. The experiment presented in Section II showed that cows induced to lose their pregnancy by progesterone depletion or embryonic demise at 39 d of gestation had a steady decrease in Pregnancy Associated Glycoproteins (PAG) after treatment when compared to cows maintaining their pregnancy. In Section III, two decision support systems created based on Markov-chain simulation models were described. These models are capable of simulating the dynamics of a dairy herd based on input reproductive, productive, and economic parameters. The resulting reproductive performance determines the economic value of the different reproductive management programs under consideration. Results from case studies performed using these decision support systems demonstrated that the economic value of a reproductive program is influenced by many factors. Among the most critical are the percentage of cows inseminated after a detected estrus versus timed artificial insemination and the outcome of these artificial insemination services.
机译：进行了一系列实验以发展排卵协议的重新同步，以提高定时人工授精服务的生育力，评估循环孕酮浓度对GnRH治疗后垂体腺垂体LH分泌的影响（第一部分），并评估两者之间的相关性。泌乳奶牛诱发妊娠流失后胚胎死亡和激素动力学的时机（第二部分）。此外，还基于模拟模型创建了决策支持系统，以在选择奶牛群的生殖管理计划时做出基于经济的决策（第三部分）。第一部分中的三个实验结果表明，在重新同步开始之前使用发情周期的预同步可提高泌乳奶牛重新同步服务的生育能力。预同步通过增加重新同步开始时具有功能性黄体的母牛的百分比和对方案注射作出响应的母牛的百分比，可以有效地提高生育能力。而且，与在GnRH治疗时具有功能性黄体的母牛体内观察到的黄体酮浓度升高相似，可以抑制LH从垂体的释放。孕激素对GnRH诱导的LH释放的这种抑制作用可以通过增加GnRH的剂量来部分克服。在第二部分中进行的实验表明，与维持妊娠的母牛相比，在妊娠39天时因黄体酮耗竭或胚胎死亡而失去妊娠的母牛在治疗后的妊娠相关糖蛋白（PAG）稳定下降。在第三节中，描述了基于马尔可夫链仿真模型创建的两个决策支持系统。这些模型能够根据输入的生殖，生产和经济参数模拟奶牛群的动态。由此产生的生殖绩效决定了所考虑的不同生殖管理计划的经济价值。使用这些决策支持系统进行的案例研究的结果表明，生殖计划的经济价值受许多因素影响。其中最关键的是在检测到发情后与定时人工授精后授精的奶牛百分比以及这些人工授精服务的结果。

著录项

  • 作者

    Giordano, Julio O.;

  • 作者单位

    The University of Wisconsin - Madison.;

  • 授予单位 The University of Wisconsin - Madison.;
  • 学科 Agriculture Animal Culture and Nutrition.;Biology Physiology.;Economics Agricultural.
  • 学位 Ph.D.
  • 年度 2012
  • 页码 435 p.
  • 总页数 435
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

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