Changes in the group associations of free-ranging beef cows at calving

Abstract

Dyadic association between individuals forms the basis of group structures for herding animals. Group associations and social bonds are dynamic and can result in the establishment of new subgroups. The onset of parturition and the introduction of an offspring create a social change for a mother that is part of a herd. There is a need to nurture the young, develop and maintain a strong maternal bond, and build or maintain social networks within the larger herd. The present study explored associations within a herd of cattle that included pregnant cows and cows with calves (maternal cows). Group dynamics were determined by daily observations of group associations over an 11-week period. During the period, some pregnant cows calved and it was possible to quantify their associations before and post-calving. The associations between individual cows were quantified using a half-weight index (HWI). The HWI data for the maternal and pregnant class of cows were compared. The overall HWI data and the individual class data (pregnant or maternal) were tested against a random model, using data that were generated using permutation methods. There were significant differences in the associations of the pregnant and maternal cows; the maternal cows had stronger associations with other maternal cows while the pregnant cows showed evidence of weaker associations with other pregnant cows and the maternal cows. As pregnant cows calved, they developed stronger associations with other maternal cows. The present study provided evidence that pregnant cows prefer to maintain a degree of isolation, but strengthen their social bonds with other mothers as they enter a maternal phase.

Pregnant cattle associations and links to maternal reciprocity

“…The detailed observation data has previously been reported (Finger et al, 2014) and included detailed measures of association patterns. Over a series of three 4-week deployments, all adult cattle were fitted with a Sirtrack proximity logger to record the frequency and duration of close proximity encounters (Patison et al, 2010).…”

“…These events result in dynamic preferential associations, for example during an oestrus event cows will form sexually active groups (Orihuela, 2000). Observational studies have shown that cows during pregnancy preferentially associate with other pregnant cows but overall they have lower association levels compared to cows that have calves (maternal cows) (Finger et al, 2014).…”

Do Movement Patterns of GPS-Tracked Cattle on Extensive Rangelands Suggest Independence among Individuals?

“…The HWI is one the most commonly used measures of association in studies evaluating association patterns between individual animals [26], and has been used in understanding factors that affect associations of cattle [27] and bison [28]. The HWI calculated the proportion of the GPS location fixes where cattle were within 75 and 500 m distances from each other relative to the total number of GPS location fixes recorded for each animal [29].…”

Virtual herding for flexible livestock management – a review

“…However, a proper understanding of free-ranging animal behaviour requires both small plot-and landscape-based data in which the interactions among plants (Soder et al 2007) and livestock (Estevez et al 2007) influence foraging behaviour at both these scales. Foraging behaviour is affected by both the physiology of animals (Provenza et al 2007;Finger et al 2014) in addition to many factors external to the animal (Anderson 2010) and both are significant when large numbers of physiologically diverse animals forage on large heterogeneous landscapes (Barnes and Hild 2013;Norton et al 2013). Therefore, scale is a key to our understanding of the plant-animal interface as it influences the behaviour of livestock.…”