Comparative effectiveness of cryoprotective diluents for rooster seed

Abstract

The preservation and use of frozen/ thawed male sperm is important for maintaining the biodiversity of poultry and will eventually play an important role in breeding, allowing greater flexibility in breeding programs. This use of thawed semen is advisable only at a high level of its fertilizing ability. Trehalose is a promising natural component in cryoprotective media for rooster semen due to its exceptional ability to neutralize cold stress. The purpose of the study was to determine the effectiveness of using trehalose as part of a medium for cryopreservation of rooster semen based on the Russian development - Leningrad cryoprotective medium (LCM-control). The composition of the LCM-T20 experimental medium with the addition of trehalose at a concentration of 9.5 mM has been developed. The mobility indicators of thawed rooster semen (Rhode Island Red breed, ♂n=10) did not differ significantly depending on the composition of the medium. Significant differences (p <0.05) were obtained in terms of egg fertilization: 86.0% when using the LCM-T20 medium and 79.0% using LCMcontrol and in assessing the state of the vitelline membrane of the egg yolk (p <0.001). The fertilization rate of eggs at a level acceptable for thawed semen of 50% was maintained until the 10th day (20th day of egg collection) from the last insemination when using the LKS-T20 medium. The functional usefulness of thawed sperm was maintained for 15 days (the 25th day of egg collection) from the last insemination when using the LCM-T20 media - egg fertilization was 15.0%, the average number of points of interaction of sperm with the vitelline membrane of the egg yolk was 345.2 pcs/cm2. When using the LCM-control diluent, the functional ability of thawed spermatozoa was absent during the same control periods. The achieved high level of egg fertilization when trehalose was included in the cryoprotective diluent in combination with the method of freezing rooster semen in pellets confirms the feasibility of introducing the LCMT20 diluent into the technology for preserving the genetic diversity of local and indigenous breeds of chickens using in vitro methods.