ABSTRACT

Maternal behavior has been related to ewe’s reactivity, as more reactive ewes might have greater risk of presenting worse maternal ability. This study aimed to determine the association between maternal behavior score (MBS) of Corriedale ewes with their physiological and behavioral variables measured at weaning of their offspring within two handling systems. Data from 335 ewes with average (± SE) age of 3.1 ± 1.8 years and 46.5 ± 6.1 kg of body weight were used. Experimental farms were classified into two handling systems: intensive (n = 3) and extensive (n = 2), based on stocking density and nature of human-animal relationships. Maternal behavior was evaluated in the field within 24 h after delivery, using a 6-rated scale (1 = poor to 6 = excellent). This scale takes into account the distance the ewe takes from the lamb when the lamb is restrained by an observer. The temperament of the ewes was evaluated during an arena test, at the weaning of the lambs, and was divided into two phases: social isolation and human presence. Data were subjected to principal component analysis and logistic regression. Logistic regression of principal factor (PF) scores in MBS showed that physical activity during the isolation phase increased in 1.57 (CI: 1.02 to 2.42; P < 0.05) the probability of extensively handling ewes showing high MBS (≥4), while in intensively handling ewes, logistic regression showed that the number of vocalizations in both phases of the arena test increased in 1.64 (CI: 1.12 to 2.4; P < 0.05) the probability of ewes having high MBS. Albeit the handling systems are not comparable, MBS was positively associated with some behavioral variables measured at the arena test.

摘要

母性行为与母羊的反应性有关，因为反应性更强的母羊可能有更大的风险表现出更差的母性能力。本研究旨在确定 Corriedale 母羊的母性行为评分 (MBS) 与其后代在两种处理系统中断奶时测得的生理和行为变量之间的关联。使用了来自 335 只平均 (± SE) 年龄为 3.1 ± 1.8 岁和 46.5 ± 6.1 kg 体重的母羊的数据。根据放养密度和人畜关系的性质，实验农场分为两种处理系统：集约化（n = 3）和粗放（n = 2）。在分娩后 24 小时内，使用 6 级量表（1 = 差到 6 = 优秀）在现场评估母体行为。这个比例考虑了当观察者束缚羔羊时母羊与羔羊之间的距离。母羊的性情是在羔羊断奶时的竞技场测试中评估的，分为两个阶段：社会隔离和人类存在。对数据进行主成分分析和逻辑回归。MBS 中主要因素 (PF) 得分的逻辑回归表明，隔离阶段的体力活动增加了 1.57（CI：1.02 至 2.42；P  < 0.05）广泛处理母羊的概率显示高 MBS（≥4），而在密集处理母羊时，逻辑回归显示竞技场测试两个阶段的发声次数增加 1.64（CI：1.12 至 2.4；P  < 0.05) 母羊具有高 MBS 的概率。尽管处理系统不可比，MBS 与竞技场测试中测量的一些行为变量呈正相关。