Prevention of reproductive disorders in sows

Data collection related to production performances and health parameters was developed in 31 intensive pig farms in Portugal (from 100-800 sows each) in 1,580 of 10,000 sows over 7 yr (1985-1992). Using prospective surveys and subsequent preventive veterinary medicine programs in pig farms, we demonstrated the value of risk-factor analysis in the improvement of production performances: an increase in litter size from 9.15 piglets born/litter (sd 2.93) to 13.4 (sd 2.13); an increase in number of weaned piglets per sow per year: 15.73 (sd 1.93) to 20.46 (sd 1.92); and a decrease in returns to oestrus (25.3 to 2.3%).