Spermatological and Bacteriological Evaluation of the Semen of Breeding Dogs

Abstract

Semen evaluation is an indispensable concept for prediction of fertility in animals. Here, we used 105 stud dogs of different breeds (German shepherd, Rottweiler and pit-bull) to investigate the spermatological characteristics (sperm motility, concentration, morphology and viability) and microbiological studies of dogs’ ejaculates. The results of spermatological characteristics revealed that sperm motility decreased to 25%, 40% and 30% and sperm cell concentration clearly decreased to 18 x 10⁶, 27 x 10⁶ and 50 x 10⁶ in the abnormal semen samples of German shepherd, Rottweiler and pit-bull dogs, respectively, while the sperm abnormalities increased in the abnormal ejaculates of different breeds of dogs. Moreover, percentages of sperm viability were 45%, 30% and 50% in German shepherd, Rottweiler and pit-bull dogs, respectively. Bacteria were isolated from abnormal semen samples either in single or mixed infections. S. aureus was the dominant bacteria causing single infection followed by E. coli. In mixed infections, S. aureus+ E. coli were the highest, followed by S. aureus + Streptococcus spp. Sensitivity of antibiotics against isolated bacteria revealed that levofloxacin was the most effective antibiotic against microorganisms, followed by ciprofloxacin. In conclusion, sperm patterns of abnormal semen deteriorated in motility, concentration, morphology, and viability. S. aureus is the predominate microbe contaminating dogs’ ejaculates. Levofloxacin and ciprofloxacin were the ideal antibiotics to be used against the bacteria in semen samples of stud dogs. The Comet assay could be used to assess dog sperm oxidative damage and, subsequently, evaluate semen quality.