Evaluation of quail and turkey egg yolk for cryopreservation of Nili-Ravi buffalo bull semen

Egg yolk is used as a cryoprotectant for semen in different mammalian species including buffalo. Egg yolk from different sources may affect freezability of buffalo bull semen. Quail egg yolk (QEY) and turkey egg yolk (TEY) in Tris-citric acid extender was evaluated for post-thaw quality and in vivo fertility rate of cryopreserved buffalo bull semen. Ejaculates were collected on weekly basis from six Nili-Ravi buffalo bulls (12 ejaculates/bull) for a period of 6 weeks and diluted at 37 °C with tris-citric egg yolk extender (50 × 106 motile spermatozoa mL−1) containing different levels of QEY or TEY (5%, 10%, 15%, and 20%) or 20% chicken egg yolk (CEY; controls) and cryopreserved. Percent post-thaw sperm motility (48.3 ± 3.8), plasma membrane integrity (67.9 ± 5.3), live/dead ratio (68.2 ± 5.0), and viability (50.5 ± 3.7) were recorded higher (P