Cow-calf contact in dairy farming - Norwegian cow-calf contact (CCC) farmers’ practice and perceptions, and effects of CCC on behavior and performance on pasture

Summary in the original language of the document

The separation of cow and calf within the first day after calving is common practice in dairy farming, but cow-calf contact (CCC) systems are receiving increased attention from different stakeholders. This interest is driven by consumers’ increasing concerns about animal welfare, and their desire for more ethical and natural rearing of animals. Surveys have shown that many consumers prefer to see cows together with their calves, and that cattle have access to pasture. At the outset of this PhD work in 2020, existing research on the experiences and perceptions of farmers regarding CCC systems was limited. Additionally, there was a lack of knowledge about keeping dairy cows and their calves together on pasture. The main aim of this thesis was to gain knowledge about how Norwegian dairy farmers practice and perceive their CCC systems and about the effects of CCC on calf behavior and cow-calf performance on pasture. To accomplish the study’s main aim, three specific objectives were defined. The first objective involved exploring how Norwegian dairy farmers with CCC systems practice these systems, along with how they experience and perceive the interrelationships between cows and calves and humans within these systems (Paper I). This objective was achieved through interviews with 17 Norwegian farmers (from 12 dairy farms) who practiced CCC systems where the calves remained with their dams for at least four weeks. The second objective aimed to compare the behavior of pastured dairy calves with or without their dams by examining their calf hide usage, lying behavior, grazing, playing, allogrooming between calves, and by describing their behavior in a food neophobia test. It also aimed to describe the calves suckling or sucking milk, allogrooming between cow and calf, and calf vocalizations post-weaning (Paper II). The third objective aimed to evaluate performance in pastured dairy cows and calves with or without CCC through cow machine milk yield and composition, and calf daily body weight gain. Additionally, it aimed to study cow body weight and condition, calf intake of concentrates, artificially reared calves’ milk intake, and cow and calf health (Paper III). For the second and third objectives, a pasture study was conducted with 20 cow-calf pairs allocated to two treatments with two groups per
treatment: Cow-calf contact (CC, n=10 pairs) and early separation (ES, n=10 pairs). The interviewed farmers had diverse practices and perceptions regarding CCC systems. All of them practiced CCC in the indoor cow areas, and seven of the farms also practiced CCC on pasture. The duration of CCC ranged from 6-8 weeks to 4 months, and the duration of full CCC from 2 days to 3 months. On 10 of the farms, calves were allowed to suckle throughout the milk feeding period, whereas the remaining two farms continued to provide milk to calves after separation from their dams. Generally, the cows were perceived as being good mothers. When the farmers
had developed good relationships with the cows so that cows and farmers felt safe around each other, they could develop good relationships with the calves as well. According to the farmers, the calves learned from the cows, e.g., feeding behavior and how to be a cow in their environment. Animal welfare was important to the interviewed farmers, and they enjoyed practicing these systems (Paper I). In the pasture study, calf behavior was influenced by CCC. CC calves spent less time using a calf hide compared to ES calves (mean across weeks 3, 6 and 9: 12.8 vs 56.2 %), but the differences were dependent on age for the other behaviors (Paper II). The lower machine milk yield in CC cows compared to ES cows (weeks 0-6: 10.8 vs 34.5 kg/cow/day) persisted at least till weeks 10-11 postpartum when CC cows nursed until week 8 (weeks 10-11: 23.7 vs 32.0 kg/cow/day). Inhibited milk ejection was a challenge during milking of CC cows. The challenge was prominent with primiparous cows, as well as during weaning and separation from their calves. The mean fat content in machine milk was lower in CC cows compared to ES cows, although not significantly (week 5: 2.6 vs 3.3 %). Lactose content was significantly lower in machine milk from CC cows than ES cows (4.5 vs 4.9 %). Post-treatment, composition of machine milk became similar in both treatments (Paper III). The interviewed farmers expressed that higher weight gain and improved health in their calves were among the main benefits of CCC systems. However, in the pasture study, artificially reared calves were fed milk close to ad libitum, and no difference was found between treatments in terms of calf weight gain during any of the examined periods (weeks 0-6, CC: 1.34 vs ES: 1.25 kg/calf/day, weeks 6-9: 1.05 vs 0.92 kg/calf/day, week 9 to 6-7 months: 1.06 vs 1.16 kg/calf/day). Similarly, there were no notable differences in calf health across treatments.
Further research is necessary to enhance milk ejection during milking of dairy cows rearing their calves on pasture and to minimize stress associated with weaning and
separation of pastured cows and calves.