The production characteristics of organic dairy herds in the UK

摘要

Thirteen organic dairy herds in the South of England and Wales were surveyed for three years (1997 to 1999). Monthly milk recording data (National Milk Recording Plc., UK) were analysed using the Interherd~(TM) software. Herds were visited at three-month intervals to collect supporting data. Individual case-studies were also conducted to describe feeding and breeding management. A total of 3,526 full lactations from 1,779 cows were analysed. The overall mean lactation yield was 6,027 (s.d. 1,398) kg.Mean 305-day lactation yield was 5,767 (s.d. 1,238) kg. Large between herd variations were observed in all these variables. Herd averages ranged from 5,080 to 7,670 kg /cow/lactation. The overall means of fat and protein content were 4.03% and 3.29% respectively. The mean of all lactation geometric averages of somatic cell count (SCC) measures was 171,000 cells/ml. Lactation trends were analysed and related to estimated fertility parameters. Average peak yield was 26.2 kg/day, and average lactation persistency was 0.78. Calving patterns were scattered, with both autumn and spring-calving herds. Average calving intervals were 385 (s.d. 14) days. The average interval from calving to first service and average services per conception were 80 (s.d. 9) daysand 2.3 (s.d. 0.4) services per conception respectively. There were large differences between the herds. The influence of genetic merit (PIN) on yield was also examined. A herd model was used to evaluate herd productivity and economic efficiency. Management and research recommendations were developed from the results.