Main aspects in use of sexed semen in cattle breeding

The use of sexed semen in cattle breeding becomes increasingly important in worldwide. Up to date sexing technologies provide an ability to sort spermatozoa with acceptable sperm quality and ensure production of animals of the desired sex. Motivation for use of sexed semen can be the need for rapid renewal of the herd, the desire to increase the genetic level, the requirements for animal welfare and the reduction of costs for maintaining ecological sustainability. Many factors at different levels such as selection of female animals for insemination and type of sexed semen, technological features of the farm and reproductive management affect the conception rate. The current literature analysis shows that the introduction of artificial insemination with sexed semen is an effective tool to accelerate genetic progress. An additional benefit is improvement of the animal welfare by reducing difficult births and low production of the undesired male offspring. Optimization of the animal number in the herds leads to reduction of the greenhouse gases and the waste products from animal husbandry. The pregnancy rate after artificial insemination with sex-sorted sperm is variable and different reasons can lead to unsatisfactory results. This requires a preliminary analysis of their effects and taking measures to minimize their negative impact on the reproductive process. Achievement of economic profitability is related to choosing an appropriate strategy for use of sexed semen, taking into account the specific conditions in the farm. The presented information can be useful in the preparation of various policies for optimization of the reproductive process and development of sustainable cattle breeding in Bulgaria.