The challenges in reproductive management of South American camelids

Abstract

South American camelids are a major source of wealth for high Andean populations of Peru, Bolivia, Chile, Argentina and Ecuador. Reproductive management of any domestic species requires knowledge of its reproductive physiology. The reproductive performance of domestic camelids is quite poor, with reported birth rates not exceeding 50% in farming systems at the community level. One of the most important features in the reproductive physiology of the camelids has been determined: the condition of induced ovulation, which requires external stimuli such as copulation for ovulation to occur. Also pertinent is the presence of a protein called «Ovulation Inducing Factor» (OIF) in the seminal plasma of alpacas and llamas. The female camelids do not have estrous cycles like other species, rather in the absence of copulation they remain in a state of receptiv-ity to the male continuously for 40 d, with a short period of rejection not exceeding 48 h. Improved nutrition seems to have a relative importance in camelids unlike that in other species under conditions of grazing natu-ral pastures. In camelids, the development of artificial insemination is limited to use of fresh or chilled semen, which makes necessary the evaluation of protocols for cryopreservation of semen, thereby contributing to the spread of genetically superior animals. As for embryo transfer, experience has shown that hormonal stimula-tion with eCG or FSH enables obtaining 4.9 ± 1.1 and 4.3±2.3 embryos in llamas and alpacas, respectively. Reports in the literature on in vitro fertilization are still scarce. Use of the OIF of seminal plasma is an alterna-tive aid to improve reproductive indices, but studies are still needed on semen and embryo cryopreservation.