Cooled Storage of Canine Semen:in vitroEffects of Different Concentrations of an Antibiotic Combination on Growth of Mollicutes

Abstract

The aim of this study was to examine effects of an antibiotic combination at different concentrations on growth of mycoplasma and ureaplasma during cooled storage of canine semen (n = 20). Semen aliquots were diluted with Tris-citric acid-fructose-egg yolk extender containing either 1.0 g/l streptomycin and 0.6 g/l benzylpenicillin (control) or a combination of gentamycin, tylosin, lincomycin and spectinomycin (GTLS-1: 0.25, 0.05, 0.15 and 0.3; GTLS-2: 0.5, 0.1, 0.3 and 0.6; GTLS-3: 1.0, 0.2, 0.6 and 1.2 g/l). Samples were assessed for motility and membrane integrity by computer-assisted sperm analysis immediately after dilution and at 24, 48 and 72 h of cooled storage. Morphologically, normal spermatozoa were determined, and bacterial culture was performed at 24 and 72 h. Mycoplasma spp. were detected in 14 of 20 ejaculates (70%) with severe growth in 12 samples. A reduction but not total elimination of mycoplasma growth occurred in all GTLS extenders with the most pronounced reduction in group GTLS-3 (control vs GTLS-1 and GTLS-2 p < 0.05, control vs GTLS-3 p < 0.001). Ureaplasmas were detected in four ejaculates, and growth was reduced to the same extent in GTLS and control extender. Progressive motility in all groups, total motility in groups GTLS 1-3 and percentage of membrane-intact spermatozoa in groups GTLS 2 and 3 decreased slightly (p < 0.05) over time. In conclusion, dilution of canine semen with GTLS extender has no major detrimental effects on spermatozoa during cooled storage. It reduced the growth but did not totally eliminate mycoplasmas and ureaplasmas from cooled-stored dog semen.

Current and alternative trends in antibacterial agents used in mammalian semen technology

“…Due to the worries on the Mycoplasma sp. and Ureaplasma sp dissemination through canine semen exchange, Becher et al (2013) addressed the comparison of the effect of two antibiotic combinations, as benzylpenicillin (0.6 g/L) plus streptomycin (1.0 g/L) and the gentamicin-tylosin-lincomycin-spectinomycin (GTLS) combination at increasing concentrations (GTLS-1: 250, 50, 150 and 300 μg / ml; GTLS-2: 500, 100, 300 and 600 μg / ml; GTLS-3: 1000, 200, 600 and 1200 μg / ml), which was demonstrated for being more effective regarding the microbial control.…”

Survival capacity of Mycoplasma agalactiae and Mycoplasma mycoides subsp capri in the diluted semen of goat bucks and their effects on sperm quality

“…and Ureaplasma spp. are also thought to be transmitted via the venereal route [16]. Even in humans, the presence of U parvum, U urealyticum (Uu) or M hominis has been linked to infertility, and their venereal transmission has been reported [17][18][19].…”

Antibiotic resistance in microorganisms isolated in a bull semen stud

“…Additionally, our data indicated that more than 60% of the isolates would require concentrations greater than those recommended by the legislation to be safely reduced and only 3.9% of them would be impaired by the recommended antibiotic concentrations. Nevertheless, although antibiotics should be included in semen extenders at their recommended concentrations to allow effective control of bacterial growth (OIE, ), the efficiency of tested antibiotics appears to be decreased, as already reported elsewhere for GTLS (Becher et al, ; Gloria et al, ; Visser et al, ). Thus, periodical tests of the antibiotics regularly included in extenders are recommended at bull semen studs, especially due to the evidence that the presence of certain bacterial strains and the occurrence of some spermatozoa abnormalities attributed to bacterial contamination may be more characteristic in some bulls and may also vary across different ejaculates from the same individuals (Gonzalez‐Marin et al, ).…”

“…During sperm cryopreservation, cooling itself and the inclusion of antimicrobials in extenders may help to minimize bacterial growth (Eaglesome, Garcia, & Bielanski, ; Wentink et al, ). However, in the presence of large contamination levels (Stringfellow & Givens, ) or of bacterial resistance to commonly used antimicrobials (Becher et al, ; Gloria et al, ; Visser, Laak, & Jansen, ), such processes cannot fully assure microbiological safety to the final product. Thus, extenders avoid bacterial growth until a given threshold that may induce negative effects on sperm quality (Althouse, ).…”