Effects of dietary supplementation of Vitamin A on fertility and biochemical characteristics of oviductal and uterine flushings

Abstract

We decided to study the effects of dietary vitamin A supplementation on the fertility and the characteristics of the oviductal and uterine flushing’s of gilts because in our thermally harsh environment pigs tend to consume less feeds than needed and so expose themselves to some nutritional stress. The experimental diets contained 12,373.8 and 16,373.8 IU of vitamin A per kg. Although supplemented gilts came into puberty 21 days later, they were significantly heavier at puberty with higher conception rate than their counterparts and had a higher embryo mortality resulting in highly reduced litter size. Results on the AChE, protein and cation levels of the oviductal and uterine flushings indicate that supplementation adversely affected the quality of these tubal environments for proper embryogenesis. The results of this study thus show that dietary vitamin A supplementation above 10,000  I.U. per kg of feed is not a commercially important factor and cannot be recommended for pig production in the humid tropics.  Key words: Vitamin A, diet, gilts, fertility, Tropics