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Comparative performance of dairy cows in low-input smallholder and high-input production systems in South Africa
S Abin1, C Visser2, C B Banga3
1Department of Animal and Wildlife Sciences, University of Pretoria, Pretoria, 0002, South Africa. samuelabini@gmail.com.
Abstract:
The aim of this study was to benchmark the performance of dairy cows in the low-input smallholder system against their counterparts in the high-input system, in South Africa. Data comprised of cow performance records from the national dairy recording scheme. Performance measures included production (305-day yields of milk, fat, and protein), lactation length, somatic cell count (SCC), and reproductive traits, represented by age at first calving (AFC) and calving interval (CI). Least squares means of each trait were compared between the two systems, and lactation curves for production traits and SCC were plotted for each production system. Mean yields of milk, fat, and protein were significantly (P < 0.05) lower in the smallholder (4097 ± 165, 174 ± 5.1, and 141 ± 4.5 respectively) compared to the high-input system (6921 ± 141, 298 ± 4.7, and 245 ± 4.1 respectively). Mean lactation length was significantly (P < 0.05) shorter for the smallholder (308 ± 15.1) than the high-input system (346 ± 12.8). Log-transformed somatic cell count (SCS) was, however, significantly (P < 0.05) higher in the smallholder (2.41 ± 0.01) relative to the high-input system (2.27 ± 0.01). Cows in high-input herds showed typical lactation curves, in contrast to the flat and low peaking curves obtained for the smallholder system. Cows on smallholder herds had their first calving significantly (P < 0.05) older (30 ± 0.5) than those in the high-input system (27 ± 0.5). There was, however, no significant difference (P < 0.05) in CI between the two systems. These results highlight large room for improvement of dairy cow performance in the smallholder system and could assist in decision-making aimed at improving the productivity of the South African dairy industry.
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