Lipids in the reproduction of sires

The main class of nutritional interest for lipids are fatty acids (FA), which correspond to 90% of triglycerides, the main form of lipid storage in both plants and animals. FAs serve as a source of energy in the diet of cattle; however, they also have an important non-caloric effect on animal organisms as they are important components of the physical and functional structures of cells and participate in the composition of steroid hormones. As such, research has studied the improvement of semen quality through the provision of polyunsaturated FAs in bull diets, as well as the use of FAs in semen extenders in order to reduce damage to sperm cells, which can alter lipid composition and the quality of frozen sperm. Therefore, the objective of this work was to review the effectiveness of lipids on reproductive efficiency, based on their effects on semen quality and hormonal production. Supplementation with polyunsaturated FAs positively alters semen composition and in vitro fertility; however, results vary according to the type of FA used, the method of administration, and its quality. Fish oil and linseed oil showed better results in qualitative parameters in fresh and thawed semen. The use of cyclodextrins to incorporate or extract cholesterol from plasma membranes can also improve the viability of cryopreserved semen.