Effect of different proteolytic enzymes on liquefaction of semen of dromedary camel

Abstract

In most of domestic animals, semen biology is well studied, but it is not so well studied in camelids particularly in dromedary camels. In camelids, the ejaculated semen is highly viscous, so before its evaluation and processing for preservation, it is necessary to be liquefied. Our study was designed to evaluate the effect of three different enzymes (0.1% Collagenase, 0.5 X Accutase, 0.1% Trypsin-EDTA - Ethylene-diamine-tetra-acetic acid) on seminal viscosity at different time intervals along with its effects on seminal parameters. Semen was collected from the six adult healthy male camels using female camel as dummy. Bovine artificial vagina was used for the semen collection and ejaculate was kept at 37ºC for further processing after its collection. All three enzymes were diluted in 1x phosphate buffered saline (PBS) and the semen samples were kept at 37ºC. The samples were evaluated at different time intervals 0, 5, 10, 15, 30, 60, 120 and 240 min (T0–T240) for viscosity and it was evaluated by pipette method. Immediately after collection, the viscosity was very high, and no sperm mass motility was seen. However, after enzyme treatment viscosity was showed declining trend in all treatment groups compared to control. In trypsin treated group maximum motility was reached in 15 minutes. Live-dead percent was observed to be similar among treatment groups. Observations on liquefaction of semen revealed that use of enzymes decreasing the viscosity but with different rates.