The effects of cow-calf-contact rearing on dairy animals' social traits - a pilot study

Early separation of the calf from the dam, mostly within 24 h after birth, is common for dairy cows, but cow-calf contact (CCC) rearing gets increasing interest from both practice and science. CCC rearing allows calves suckling their dam or foster cows for several weeks after birth. The early social environment can impact the development of social behaviour and personality traits. In this study, we investigated the effect of CCC as compared to early separation and rearing in a calf group during the first three month of life on social traits. Eighteen female Blackand-White-German-Holstein heifers and calves reared in a CCC system (Contact, n = 9) or with early separation and milk from an automated milk feeder (Automat, n = 9) in the first 12 weeks of life were studied after weaning (at least 6 months old) in two situations - in their respective social group and in a sociality test. The spontaneous social behaviour was recorded for 5 h per animal in the home pen via direct observation. The sociality test was performed in a familiar environment and comprised an isolation phase of 5 min followed by a 5 min reinstatement phase. Behaviour during the sociality test was analysed from video recordings. In addition, video material from the calving pens provided insights into the type and quantity of maternal care six Contact animals had received on the 1st and on the 3rd day of their life. Treatments were compared using linear mixed models for observations in the home pen and ANOVA for the sociality test with treatment, group and, partly, their interactions, as well as age and weight as independent variables. Potential associations of maternal contact behaviour with Contact animals' affiliative interactions later in life were analysed by Spearman rank correlations. Contact animals showed more subordinate behaviours in the herd (P = 0.004). In isolation they were vigilant more often (P <0.001) and looked longer towards the exit (P =0.014) than artificially reared animals. However, we found no treatment effect on the frequency and duration of affiliative behaviour, nor animals' latency to re-join their peers during the reinstatement-phase. There was a positive correlation between the amount of maternal contact received in the first days of life and the initiated affiliative (P = 0.043) and received affiliative interactions (P = 0.016) of Contact animals later in life. The results of our pilot study add some evidence in line with earlier findings suggesting that the allowance of maternal contact affects animals' sociality and their social competence, i.e. reacting appropriately in social situations, later in life. In addition, the amount of maternal care seems to affect later affiliative behaviour. However, further research is needed with a larger number of animals and further social situations and challenges.