Submission Number: NAS-4-5-2

Abstract Number: 105

EFFECT OF A NEW ANTIBIOTIC COMBINATION ON POSTTHAW SEMEN QUALITY OF BUFFALO AND SAHIWAL BULLS.

S Hasan, SMH Andrabi, R Munir, M Jehangir, P Shafique, Muhammad Anzar* and N Ahmad

Animal Sciences Institute, National Agricultural Research Centre, Islamabad, Pakistan. ¹

Abstract:
This study determined if the newly introduced antibiotic combination, i.e. GLT (gentamycin, linco-spectin and tylosin; CSS) is detrimental to postthaw motion characteristics, plasma membrane integrity, and sperm morphology (acrosomal and general), and reduces the total aerobic bacterial count in buffalo and Sahiwal bull semen. Ten first ejaculates, five each from a buffalo and a Sahiwal bull, with more than 60 % sperm motility were obtained in an artificial vagina under standard conditions. Ejaculates were split and diluted in Tris-citric acid extender (at 37C; 5010⁶ spermatozoa/ml), containing either GLT (gentamycin 500 g/ml, linco-spectin 300/600 g/ml and tylosin 100 g/ml), CON (streptomycin 1000 g/ml and penicillin 1000 iu/ml), or NCON (control with no antibiotics). Samples were cooled to 4C in 2 h, equilibrated at 4C for 4 h, filled in 0.5 ml straws and frozen in a controlled rate cell freezer before plunging them into liquid nitrogen. Frozen semen was thawed at 37C for 15 sec. Postthaw total aerobic bacterial counts in semen samples were determined using standard microbiological technique. Mean motilities (visual, computerized, linear and circular), velocities (straight-line, average path and curvilinear) and lateral head displacement did not differ due to antibiotics or species. Similarly, plasma membrane integrity did not vary due to antibiotics or species. Sperm cells possessing normal acrosomes (%) were higher (P < 0.01) in GLT (83.6 2.5) and CON (80.3 3.8) than in NCON (69.3 2.5). Morphologically abnormal spermatozoa (%) were lower (P < 0.05) in GLT (20.8 4.5) and CON (17.3 3.4) than in NCON (29.5 4.8). Total aerobic bacterial count (cfu/ml; median) was lower (P < 0.05) in GLT (0.65) than in CON (1.78) or NCON (3.13). In conclusion, GLT was not detrimental to postthaw motion characteristics rather had beneficial effects on sperm morphology of buffalo and Sahiwal bulls spermatozoa. Furthermore, it reduced the number of aerobic micro-organisms in buffalo and Sahiwal bull semen efficiently.

Keywords: antibiotics, semen quality, buffalo, Sahiwal

This abstract is being presented at: 8:00 AM in session:
Cryopreservation