Calcium, Magnesium and Total Antioxidant Capacity (TAC) in Seminal Plasma of Water Buffalo (Bubalus Bubalis) Bulls and their Relationships with Semen Characteristics

In order to determine calcium (Ca), magnesium (Mg) content and total antioxidant capacity (TAC) of seminal plasma in buffalo and to study their associations with the semen characteristics, 54 semen samples were collected from 10 buffalo bulls; semen quality was evaluated, seminal plasma was then harvested by centrifugation and its Ca and Mg content were estimated and its TAC determined. The Ca and Mg content of the seminal plasma (Mean ± SEM) were recorded as 22.36 ± 0.52 mg dl-1 and 11.94 ± 0.36 mg dl-1 respectively, while, its mean TAC value was 1.50 ± 0.02 mmol L-1. The mean Ca value was highly associated with sperm progressive motility, gross motility, viability (P = 0.000 for all), negatively with semen volume (P = 0.01), and with Mg and TAC values (P = 0.000 for both). The mean Mg values was highly associated with sperm progressive motility, gross motility and viability and seminal plasma Ca and TAC (P = 0.000 for all) and negatively associated with semen volume (P = 0.014). The mean TAC values was highly associated with sperm progressive motility, gross motility and viability and seminal plasma Ca and Mg (P = 0.000 for all). For further clarification of these associations, the data was categorized in three groups of excellent (Ex, >90% motile, n = 33), good (Go, 80-89% motile, n = 15) and moderate (Mo, <79% motile, n = 6) according to their percentage of sperm motility. The mean progressive motility in Ex group was 92.24 ± 0.51%, in Go group it was 81.66 ± 0.62 %, and in Mo group it was 71.66 ± 1.05 %. The mean Ca, Mg and TAC values were respectively recorded as 25.12 ± 0.29 mg dl-1, 13.78 ± 0.20 mg dl-1, and 1.57 ± 0.009 mmol L-1 in Ex, 18.74 ± 0.63 mg dl-1, 9.14 ± 0.33mg dl-1, and 1.42 ± 0.044 mmol L-1 in Go, and 17.34 ± 0.18 mg dl-1, 8.06 ± 0.25 mg dl-1, and 1.23± 0.05 mmol L-1 in Mo groups. The associations in groups are discussed. These results show that seminal plasma Ca and Mg content and TAC are associated with semen characteristics, and synergistically have an effect on motility and viability of the spermatozoa after ejaculation, which are important factors in semen fertility.