Fertilizing ability and survivability of rooster sperm diluted with a novel semen extender supplemented with serine for practical use on smallholder farms.

Semen extenders are essential for maintaining the quality of sperm during storage and assuring the success of fertility after insemination. The objective of this study was to examine the effect of a new rooster semen extender (hereinafter, NCAB) supplemented with serine on the survivability and fertilizing ability of sperm following storage. NaCl solution, the NCAB extender, and IGGKPh extender were used as treatments. In Experiment 1, different storage temperatures (5°C and 25°C) and durations of storage (0, 12, and 24 h) were used to compare the semen quality and determine the suitable storage temperature. The fertility test was performed in in-station tests and on-farm experimental trials in Experiments 2 and 3, respectively. The results indicated that the interaction effect of duration, treatment, and storage temperature on all sperm parameters was highly significant. The NCAB extender significantly improved rooster semen quality during storage for 24 h at 5°C (P < 0.01). The sperm diluted in saline solution could not survive 24 h of storage at 25°C. The fertility and hatchability rates obtained for sperm diluted with the NCAB extender were higher than those diluted with other extenders. In addition, the fertilizing capacity of the NCAB extender-diluted sperm under field conditions was significantly higher than that of the saline solution-treated sperm. In conclusion, the NCAB extender supplemented with serine and stored at a low temperature (5°C) positively affects sperm quality and fertilization.