In 1944, the first National Research Council edition published swine requirements for vitamins A and D. It was not until 1978 that vitamin E was first recognized by the NRC as an essential nutrient in swine production. Today, the greatest problem with the NRC recommended vitamin levels is the lack of university research to determine the daily requirements for highly prolific sows and for rapidly growing pigs.
Vitamin E plays a key role in muscle integrity and function, immune system and reproductive health. Vitamin E also influences birthing time and the number of stillborns. Field and university studies have shown faster and smoother delivery times after pre-partum injection.
Changes in husbandry practices such as confinement feeding and early weaning have increased the need for fat-soluble vitamin supplementation, especially vitamin E supplementation. Sows are giving birth to larger litters and the pigs are now growing at a faster rate. Paul Armbrecht, a veterinarian from Rockwell City, Iowa, states, “Go back 30 years, and sows typically had eight to nine live pigs born in a litter. Today, the average number of pigs born live is closer to 15. Also, sows used to raise 20 pigs per year, but now it’s closer to 28 or 30 pigs per sow per year.”
Sows are injected two weeks prior to farrowing.
Research confirms an injection of vitamins E, A and D to gestating sows have reduced need of birthing assistance and faster delivery times.
Proper vitamin E supplementation prior to farrowing can improve uterine muscle function allowing sows to deliver faster and easier, however, inadequate levels of vitamin E can hinder the ability of the uterus. According to Armbrecht, “Good muscle tone means a farrowing time can be reduced up to 50 minutes.
“The uterus is a big muscle, and adequate vitamin E helps reduce stillborns, because the uterus can push pigs out faster. That is why we recommend injecting the sow one week pre-partum with multivitamins again one week pre-breeding.
Injection of vitamins A, D and E one week pre-breeding (at weaning) may reduce variation in embryo size, leading to more uniform fetal development during pregnancy (resulting in a more uniform litter at birth).