EPIDEMIOLOGIC STUDIES OF PIG-DISEASES .2. POST-WEANING DIARRHEA AND PERFORMANCE IN WESTERN-AUSTRALIAN PIGS

Objective To determine in Australian pig herds the accuracy of French protocols for risk factor assessment of post-weaning diarrhoea and ill thrift. Procedure French protocols for the collection of data on healt h indicators and risk factors for post-weaning diarrhoea were conducte d on 54 batches of weaner pigs from 28 Western Australian pig herds du ring three years. Results Large variations in post-weaning performance were found. About one-third of the batches were growing at < 200 g/da y during the 3 weeks after weaning, and 54% had growth rates of < 250 g/day. Weaning age and weight of at least 30 days and 7.9 kg, respecti vely, optimised weaner performance. Other risk factors associated with little post-weaning diarrhoea and good weaner performance were high c reep feed intakes, relatively little diarrhoea as suckers, and, contra ry to expectations, large temperature fluctuations. Conclusion Overall , the 'predictability' of post-weaning problems as assessed by measure ment of risk status, was good. However, the model was less accurate at predicting the performance of a single batch of pigs.