- Fatty acids
It has been described that supplementation with fish oil and soybean oil (in a 3.9% of the diet) during the last 90 days of pregnancy until weaning results in a significant increase in fat content and immunoglobulins IgG and IgM in colostrum, leading to an increase of the litter size, survival rate and weight of the piglets at weaning.
- Proteins and amino acids
It is estimated that gilts need 10 to 13 g / day of standardized ileal digestible lysine (DIS) during early pregnancy and up to 17-18 g / day in late gestation (Zhang et al, 2011).
Likewise, the contribution of optimal threonine during early pregnancy is estimated between 4 and 7 g / day and between 11 and 15 g / day in late gestation.
Isoleucine is also considered a limiting amino acid in typical diets based on cornmeal and soybean. The requirement of isoleucine for multiparous sows increases more than double from early to late gestation (from 3.6 to 9.7 g / day, respectively) and is necessary for the development of breast tissue and fetal growth in the last stage of pregnancy (Franco et al, 2013).
Piglets of sows fed diets high in fiber (up to 40%) based on pectin residues or sugar beet pulp have a higher consumption of colostrum, a greater weight during the period of colostrum intake (Theil et al, 2014), and lower mortality rate (Louis et, 2013).
For example, vitamin E (or α-tocopherol) is a nutrient of critical importance for all sows raised in confinement. Vitamin E is not synthesized by the body, therefore, all sows require dietary sources of vitamin E to meet their metabolic needs. The newborn pig is deficient in vitamin E due to the low placental transfer, and therefore, totally dependent on colostrum and milk for its obtention (Lauridsen et al, 2002).
Sows fed a basal diet supplemented with additional vitamin E, with a total content of 250 IU / kg, have an increase in the concentrations of immunoglobulin G (IgG) and immunoglobulin A (IgA) in colostrum and have piglets with a higher daily gain average weight (ADG) and better humoral immunity, compared with sows fed a basal diet (Wang et al, 2017).
It has been shown that sows fed with yeast derivatives (YD) produce 23% more colostrum, and with a higher percentage of fat than sows without YD supplement. In addition, the consumption of colostrum of piglets of these sows is 13% higher than piglets of sows without dietary supplementation. Dietary supplementation with YD also results in an improvement in the productivity of the sows, by means of the significant increase in the average weight of the piglets and the subsequent weight at weaning (Shah et al, 2017)