Male reproductive biotechnologies in South American Camelids Part II: Semen dilution, cryopreservation and artificial insemination.

Even though South American Camelids (SAC) are a rustic species, adapted to harsh environments, their ability to reproduce is low in their natural habitat. Conception and birth rates in camelids vary from 50 % to 90 %. This depends on the mating system used, sire and dam fertility, postpartum interval, environmental conditions, and nutrition. Reproductive biotechnology can reduce generation intervals and quickly spread high-quality genetics, addressing the growing need for genetically superior animals. The advantages of using artificial insemination (AI) and semen preservation are widely known. However, no cryopreservation protocol providing an acceptable sperm survival and pregnancy rate after thawing is currently available for SAC. Not having an effective semen cryopreservation protocol has hindered rapid genetic improvement and efficient use of males. For all these reasons, this biotechnology is currently only used for research purposes but not commercially in SAC. In Part I of this review on reproductive biotechnology, the initial steps of semen and/or sperm collection, evaluation and handling were discussed. The objective of Part II of the review is to describe the progress achieved in semen or sperm dilution, cooling and freezing. Current results obtained using AI in SAC will also be covered.