Seasonal infertility in UK pig production
2 TS » Health » Seasonalinfertility »
Research partners: University of Leeds
Sponsors: BPEX
Duration: 2009 – 2011
Seasonal breeding is known to occur in many mammalian species including the European wild boar, from which the domestic pig has descended. It is a recognised production problem in the pig industry, affecting herds mainly in the summer months and early autumn. Previous research has failed to provide a definitive answer as to how environmental factors affect pig production and when seasonal infertility is likely to occur on a unit.
Data collected between 2004 – 2009 from 29 UK outdoor pig units under similar management were prepared for analysis in relation to weather data (temperature, rainfall and day length) and geographical location.
To date, only farrowing rate has been examined in detail and it has been found that:
- Prolonged periods of dry weather around late lactation resulted in reduced farrowing rates (P<0.001)
- Wet weather improved farrowing rates
- Five consecutive days of temperatures below 19°C resulted in an improved farrowing rate
- More than three days of temperatures greater than 18°C during lactation reduced farrowing rates (P<0.01)
- Warm weather produced more variable farrowing rates than cool weather, irrespective of rainfall, suggesting that temperature is the main contributor to changes in farrowing rate
- Shortening day length resulted in an improved farrowing rate.
Other reproductive outputs such as wean-to-service interval, born alive piglets and return rates will also be analysed in relation to weather using various classification and modelling techniques.
There is the potential for more data to be acquired in regards to indoor herds, as well as stud data, which would allow investigation into seasonal effects on boar semen.
It is hoped that a predictive model will be able to be built and validated which would allow producers to alter their herd management in order to prevent or overcome the effects of seasonal infertility. This model will take into account all the variables which could affect sow fertility, predict whether the farm in question is likely to suffer from infertility problems and then test whether making changes, such as different gilt and sow culling management routines, will improve the situation. These changes would be easy to implement and hopefully work towards improving the consistency of pig productivity throughout the year.