Direct and associative effects for androstenone and genetic correlations with backfat and growth in entire male pigs.

In the pig industry, male piglets are surgically castrated early in life to prevent boar taint. Boar taint is mainly caused by androstenone and skatole. Androstenone is a pheromone that can be released from the salivary glands when the boar is sexually aroused.

Exploring breeding opportunities for reduced thermal sensitivity of feed intake in the lactating sow.

The aims of this study were, first, to evaluate the effects of climatic variables on daily feed intake of lactating sows and, second, to establish whether the response of sows to variation in temperature on feed intake during lactation was heritable. A total of 82,614 records for daily feed intake during lactation were available for 848 sows with 3,369 litters farrowing from January 2000 to December 2007. Climatic parameters available from the nearest weather station were maximum 24 h outside temperature, day length changes, and humidity.

Genetic parameters and predicted selection results for maternal traits related to lactation efficiency in sows.

The increased productivity of sows increases the risk of a more pronounced negative energy balance during lactation. One possibility to prevent this is to increase the lactation efficiency (LE) genetically and thereby increase milk output for a given feed intake and mobilization of body tissue. The benefits of selection for LE depend on its heritability and the relationships with other traits of interest.