López-Gatius F, Santolaria P, Mundet I, Yániz J L
Departamento de Producción Animal, Universidad de Lleida, Escuela Técnica Superior de Ingeniería Agraria, Avda. Alcalde Rovira Roure 177, 25198 Lleida, Spain.
Theriogenology. 2005 Mar 15;63(5):1419-29. doi: 10.1016/j.theriogenology.2004.07.007.
Poor detection of estrus, still a major problem in the dairy industry, has prompted the development of electronic estrous detection technologies. One of the features of estrous behavior is a marked increase in walking activity. The objectives of the present study were to evaluate the effects of various management factors on walking activity increase at estrus, and the relationship between this trait and fertility. Data from 5883 artificial inseminations (AI) conducted in two high-producing dairy herds were analyzed. Detection of estrus was performed using a pedometer system. Of the total AI investigated, 2072 (35.2%) resulted in pregnancy. The following data were recorded for each animal at AI: herd, lactation number, milk production (average for the 3 days prior to AI), lactation stage (early, mid, and late lactation), previous estrous synchronization (cloprostenol or progesterone releasing intravaginal device [PRID] for animals showing estrus within 7 days of treatment), season (warm versus cool period), insemination number following parturition, inseminating bull, inseminator, and pedometer measurements. Variables were screened for associations with walking activity by analysis of variance (ANOVA) through generalized linear model procedures (PROC GLM). Increased parity and milk production, and insemination during the warm period were associated with lower pedometer measurements. No significant effects of the herd, estrous synchronization, and lactation stage were observed. The link between walking activity and fertility was determined by applying logistic regression models. We detected no significant effects of herd, milk production, estrous synchronization, lactation stage, and inseminator on pregnancy rate. A higher lactation and insemination number, and insemination during the warm period were negatively correlated with the pregnancy rate. The likelihood of pregnancy was greater when semen from one of the bulls was used and when physical activity at estrus was increased. Our findings indicate that cow and management factors contribute intensely to walking activity at estrus, and also reveal a close link between increased walking activity and fertility.
发情检测不佳仍是乳制品行业的一个主要问题，这促使了电子发情检测技术的发展。发情行为的一个特征是行走活动显著增加。本研究的目的是评估各种管理因素对发情时行走活动增加的影响，以及该性状与繁殖力之间的关系。分析了来自两个高产奶牛群的5883次人工授精（AI）数据。使用计步器系统进行发情检测。在所有调查的人工授精中，2072次（35.2%）导致怀孕。在人工授精时为每头动物记录以下数据：牛群、泌乳次数、产奶量（人工授精前3天的平均值）、泌乳阶段（泌乳早期、中期和晚期）、先前的发情同步情况（对在治疗后7天内出现发情的动物使用氯前列醇或孕酮释放阴道装置[PRID]）、季节（温暖期与凉爽期）、分娩后的授精次数、授精公牛、授精员以及计步器测量值。通过广义线性模型程序（PROC GLM）的方差分析（ANOVA）筛选变量与行走活动的关联。胎次增加、产奶量增加以及在温暖期进行授精与较低的计步器测量值相关。未观察到牛群、发情同步和泌乳阶段的显著影响。通过应用逻辑回归模型确定行走活动与繁殖力之间的联系。我们未检测到牛群、产奶量、发情同步、泌乳阶段和授精员对怀孕率有显著影响。较高的泌乳和授精次数以及在温暖期进行授精与怀孕率呈负相关。当使用其中一头公牛的精液且发情时的身体活动增加时，怀孕的可能性更大。我们的研究结果表明，奶牛和管理因素对发情时的行走活动有很大影响，并且还揭示了行走活动增加与繁殖力之间的密切联系。
