Amelioration of physical characteristics, antioxidant capacity, and fertilizing potential of cryopreserved buck goats’ spermatozoa through Amphora coffeaeformis microalga extract

Abstract

This investigation consisted of two sequential experiments. The first one attempted to explore the effect of various levels of Amphora coffeaeformis microalga extract (ACME) supplementation to the semen medium on buck’s sperm quality. Semen samples were collected with an artificial vagina from 6 fertile Damascus bucks and then were diluted with an extender containing ACME (2.5, 5, 7.5, 10, 12.5 µl/mL) or without (control). Aliquots of diluted semen were stored and maintained at 4°C for the subsequent 48 h during which sperm traits were assessed alongside total antioxidant capacity (TAC), alkaline phosphatase activity (ALP), reduction of the resazurin dye test (RRT), and sperm DNA fragmentation index using fluorescent imaging. In the second experiment, the optimum level of ACME supplementation was used to determine the fertilization ability of spermatozoa. The obtained results of the first experiment indicated clearly that level 12.5 µl/mL of ACME achieved higher (P< 0.05) values of progressive motility, live sperm, normal sperm, and intact acrosome at 48 h of chilled preservation than those of other experimental groups. Moreover, addition of 12.5 µl/mL ACME to the semen extender increased (P<0.05) TAC at T₄₈ of the preservation period. Correspondingly, ACME supplementation at level of 12.5 µl/mL reduced the secondary sperm abnormalities at 48 h of chilled preservation. The results of DNA fragmentation index (DFI) improved (P<0.05) with level of ACME (12.5 µl/mL), compared with the other levels or control specimens at T₄₈ h of storage period. Consequently, the optimum level of ACME (12.5 µl/mL) yielded higher (P<0.05) in fertilization rate compared to control. The emerged results accentuate the protective role of Amphora coffeaeformis microalga extract on cryopreserved spermatozoa. Furthermore, addition ACME at level of 12.5 μg/ mL to semen extender appeared to be the optimum level to express the valuable effects on the semen quality, antioxidant activities, DNA fragmentation index, and fertilizing potentials.