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Comparison of calving data among Jersey, Jersey x Holstein crosses, and Norwegian Red x Holstein x Jersey crosses
The dairy at the Center for Environmental Farming Systems (CEFS) has been a pasture-based herd of Holstein (H), Jersey (J), and crosses of those breeds but now is transitioning into three breed groups: Group A includes pure J and mostly J being bred to become pure Jerseys; Group B includes a two-way criss-cross of H and J breeds by alternating sire breeds each generation; whereas Group C is a three-way rotational cross with Norwegian Red (NR) introduced as the third breed in 2014. The objective of the study is to examine differences in calving characteristics among breed groups across two calving years. Groups included: A (83 calves, J sires), Bh (48 calves, H sires), Bj (60 calves, J sires), and C (94 calves, NR sires), respectively. Breed group (P<0.05), interaction of parity x calving year (P<0.01), and the 3-way interaction (breed group x parity x year; P<0.05) significantly affected gestation length. Least squares means for birth weight for groups A, Bj, Bh, and C, respectively were: 26.8 kg ± 0.5 kg, 27.7 kg ± 0.7 kg, 32.9 kg ± 0.7 kg, and 34.5 kg ± 0.5 kg. Parity (P<0.001), breed group (P<0.001), and calf gender (P<0.001) all affected birth weight. Multiparous cows had heavier calves than first parity cows (P<0.001). Group C calves were heavier than Group Bj (P<0.001) and Group A (P<0.001) calves. Group Bh calves were also heavier than Group A calves. Male calves weighed more than female calves (P<0.001). Breed group was associated with calving difficulty (P<0.05). Cows delivering NR crossbred calves had more difficulty than cows having Group Bj calves (P<0.05). Based on current data and earlier studies, use of either NR or H sires results in heavier birth weights and potentially more challenges at calving.
Keywords: Crossbreeding, gestation, calving