Development of a method for preparing alpaca semen by colloid centrifugation

Abstract: Alpacas belong to the South American Camelids and they share many characteristics with other camelids. The camelids have unique reproductive characteristics; one example of that is the high viscosity of their semen. The latter has caused problems for many years, since it causes difficulties in collecting, handling and processing the semen for artificial insemination. Several methods for handling alpaca semen have been attempted; One that has been doing particularly well in different studies is Single layer Centrifugation (SLC), which has shown promising results in species such as stallions, boar, goat, donkey, llama and camel. The aim of this study was to examine whether the semen could be liquefied in Tris-citrate-fructose to enable the spermatozoa to swim freely and whether SLC could be beneficial in processing alpaca semen as it has been in other animal species. This study took place at San Marcos University in Lima; a total of 9 ejaculates from 4 different alpaca males were assessed. The ejaculates were liquefied with tris-citrate-fructose, prepared with SLC and thereafter evaluated for volume, concentration, motility, membrane integrity, vitality and morphology. The assessments took place both directly after collection as well as after 24 hours of storage in 4 degrees Celsius. The evaluation were made manually with a light microscope. The results were compared to control samples. The results showed that it was possible to liquefy alpaca semen in Tris-citrate-fructose because all the samples had spermatozoa that swam freely after being subjected to Tris-citrate-fructose. Significantly better values (p<.05) in motility, in some aspects of vitality and abnormal tails, but not membrane integrity were shown for spermatozoa that had been processed with SLC. These results demonstrate that SLC might have a beneficial effect on the quality of alpaca spermatozoa, but to draw more reliable conclusions there is need for further studies.