Fatty acids and reproduction in the pig

摘要

Sow productivity is comprised of various components that determine the number of piglets attaining slaughter weight per annum. As far as direct effects of reproduction are concerned, the main factors involved are ovulation rate of the sow, successful fertilisation, the extent of pre and post natal mortality and parturition-rebreeding interval. In quantitative terms, ovulation and fertilisation is about 90 percent successful as judged by first service returns (MLC, 2001) and is therefore much less of a problem than in the dairy industry. Mortality between birth and weaning is around 10 percent of pigs born alive (MLC, 2001). Ante-natal mortality is more difficult to estimate, about 1 piglet / litter is borne dead or mummified (9 percent of pigs borne alive, MLC 2001) but this will only represent a small fraction of ante-natal mortality. Pope (1994) estimated a mortality of 27 percent before day 35 of pregnancy. There is therefore scope for improvement in all aspects of reproductive performance. The correct nutrition of the sow and to a lesser extent the boar has a major effect on reproductive success of the sow; however ration formulation has to date correctly focussed on major dietary constituents and trace elements and vitamins. Less attentionhas been paid to the type and quantities of fatty acids in the diet and their influence on reproductive success.