The use of combined ringer diluent on calcium concentration, malondialdehyde levels, and ultrastructure of gaga chicken’ sperm post-freezing

The Gaga chicken, an indigenous Indonesian breed with distinctive vocal characteristics, is facing a population decline. Sperm cryopreservation is a potential method to preserve its genetic resources. This study aimed to evaluate the effects of different base diluents on calcium ion (Ca2+) concentration, malondialdehyde (MDA) levels, and sperm ultrastructure after freezing. Four diluents were tested: Ringer’s Lactate-egg yolk (RLEY), Ringer’s Acetate-egg yolk (RAEY), Ringer’s Lactate-skim milk (RLSM), and Ringer’s Acetate-skim milk (RASM). Semen was collected from male Gaga chickens using the massage method, diluted with each treatment, and packed into mini straws. The samples underwent equilibration at 5 °C for 2 h, pre-freezing for 10 min, freezing for 24 h, and thawing at 37 °C for 30 s. Results showed that RLEY produced the highest intracellular Ca2+ concentration post-thaw. MDA levels increased after freezing-thawing but were lower in RLEY than in RASM. Ultrastructural analysis revealed sperm head damage in all treatments except RLEY. Based on these findings, RLEY was more effective than RASM for preserving Gaga chicken sperm during cryopreservation, offering better protection against freezing-induced damage.

Highlights
sperm preservation of Gaga chicken is important to develop a breeding program

the use of ringer diluent Ringer’s Lactate-egg yolk (RLEY) found to be effective as cryoprotectant