Short project description

Background:
Progeny born to primiparous sows (gilt progeny) are born lighter, grow slower, have higher rates of mortality and are more susceptible to diarrhoeic disorders than piglets born to multiparous sows. Several factors such as nutritional status of the gilt/sows at the farrowing time and potential difference in milk composition could be considered as contributing factors. In general, milk consists of fat, lactose, protein, and minerals. Synthesis of the components for colostrum and milk production occurs a few weeks before parturition and keeps going during parturition. Sows gain fat during the gestation period and lose their reserve fat during lactation for colostrum and milk production.

Therefore, the backfat depots play an important role as energy reserve and influence colostrum and milk production of the sow. Considering that gilts are leaner than older sows, the lack of substantial backfat depots can be the limiting factor for sufficient milk production during the lactation period. Thus, it is important to establish if there is an association between backfat thickness, milk composition and litter performance, in case of development of management strategies that improve the health and welfare of first-litter piglets and increase their production efficiency.

The overall aim of the present project is to investigate how sows’ backfat thickness is associated with milk composition and performance of litters born from primiparous and multiparous sows.

Activities:
An observational field study will be performed on one of the conventional pig herds in Denmark (Jutland), where the milk samples will be collected from primiparous and multiparous sows, and a measure of backfat thickness will be performed. The concentrations of fat, protein, lactose, and dry matter in milk samples will be analysed by infrared spectroscopy (Milkoscan 4000, FOSS, Hillerød, Denmark). The litter and sow performance will be monitored during the whole experiment.