ABSTARCT
Propolis as natural antibiotic has lot of flavonoids, organic compounds, fatty acids steroids, amino acids and others. These ingredients may affect fertility and productivity. This study was designed to determine the effects of various concentrations of propolis powder extract or glue compared with synthetic antibiotic on motility (%), live spermatozoa (%), normality (%) and acrosomal intact (%) traits of ram spermatozoa (as indicator for semen quality), enzymatic activities of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP) and lactic dehydrogenase (LDH); penetration ability and resistance to bacterial contamination in ram semen extender. Ethanolic extract of propolis was prepared by dissolving either powder or glue (10 grams/100 ml ethanol, w/v) incubated at 37 °C for 6 hrs. Seven semen extenders included M1 (control), M2: 400μl pen-sterp and M3: 600μl pen-sterp as synthetic antibiotic; M4: 400μl and M5: 600μl propolis powder; M6: 400μl and M7: 600μl propolis glue as natural antibiotic, respectively. The results showed that semen quality traits decreased significantly (P<0.01) with incubation time in all extenders. On the other hand, all sperm parameters and penetration ability were improved (P<0.01) while enzymatic activities (ALT, AST, ALP and LDH) were significantly (P<0.01) decreased in extenders treated groups [(synthetic and natural antibiotic, either propolis powder or glue)] compared with control group. Furthermore, a higher antimicrobial activity (P<0.01) for M5 and M7 extenders were observed compared with other semen extenders. From the present results, it could be concluded that supplementation of propolis extracts either powder or glue in extended ram semen as natural antibiotic led to positive effect on different sperm characteristics, enzymatic activities, penetration ability and protection extender from bacterial contamination.