Physiological response of zaraibi Billy goats spermatozoa to soybean lecithin addition as an alternative to egg yolk varieties in semen extenders

الملخص EN

The present study was designed to determine the influence of cryopreservation action of extenders containing plant (soybean lecithin, SBL) or animal (domestic birds' egg yolk) origins on freezability and fertility of billy goat spermatozoa.

Thus, semen ejaculates (thirty-six ejaculates) were collected, evaluated and extended in Tris-citric acid with either SBL or egg yolk (EY) derived from hen (HEY), duck (DEY), goose (GEY), quail (QEY), turkey (TEY) and pigeon (PEY).

The diluted semen was packaged in 0.5 ml French straws, equilibrated for 3 hours at 5oC then frozen in liquid nitrogen (at -196°C).

The thawing of straws was attained at 37oC for 60 sec.

Percentages of progressive sperm motility, viability of sperms and injury of acrosome were evaluated at post - dilution (PD), post - equilibrium (PE) and post - thawing (PT).

Fertility rate was carried out with 24 nanny goats divided into two groups (N=12/ group) and inseminated with the best cryosurvival extenders.

The results revealed a non-significant difference between plant and bird origin extenders during PD and PE stages.

In contrast, the PT was higher (P<0.05) in motility and viability with SBL and DEY extenders than other EY species however, the same trend did not occur between SBL and DEY extenders.

The values of acrosomal abnormality was lower (P<0.05) in SBL and DEY extenders than other EY extenders.

The nanny goats inseminated by SBL and DEY extenders had a conception rate of 58.33 % and 50.00 %, respectively.

These results indicate that the spermatozoa that were preserved in either SBL or DEY extenders could protect the sperm cells during PD, PE, PT and results in the best fertility rate.

Furthermore, the present study demonstrates that SBL may represent a suitable alternative to egg yolk for semen cryopreservation in livestock species.