Changes in the aerobic vaginal bacteria load and antimicrobial susceptibility after different oestrous synchronisation treatments in goats

Abstract

The objectives of this study were to determine (i) the variation in the bacterial population, (ii) the changes in the number of aerobic bacteria, and (iii) in vitro bacterial susceptibility to different antibiotics after the use of two different intravaginal devices (silicone devices or polyurethane sponges) for 6 or 11 days in goats. During the breeding season, 25 multiparous Saanen goats were randomly allocated to four treatments. Group IS-6 (n = 6) and Group IS-11 (n = 6) goats received a polyurethane intravaginal sponge (60 mg medroxyprogesterone acetate with oxytetracycline in powder) during 6 or 11 days, respectively. Goats from groups SD-6 (n = 7) and SD-11 (n = 6) received an intravaginal silicone device (0.3 g progesterone) during 6 or 11 days, respectively. Before the introduction of the devices, at device withdrawal, and the day of oestrus we performed standard bacteriological procedures on vaginal mucus samples. The predominant bacterial flora at device insertion was gram-positive (77%), and the most frequent strain was Bacilllus sp. The samples obtained on Day 6 [SD-6: 9/12 (75.0%); IS-6: 5/9 (55.5%)] and Day 11 [SD-11: 3/4 (75.0%); IS-11: 5/5 (100%)] were predominantly gram-negative, and the most frequently isolated bacteria was Arcanobacterium pyogenes. The total number of aerobic bacteria forming colony units (CFU/mL) was greater in goats treated with inert silicon device that those treated with intravaginal sponges (P = 0.028). On device removal (Days 6 and 11), we observed more CFU/mL than on device insertion. We observed no difference in CFU/mL on day of oestrus with respect to the day of device insertion (Day 0: 41.1 ± 19.3; Day 6: 187.1 ± 51.3; Day 11: 169.1 ± 27.8; day of oestrus: 20.1 ± 25.8 CFU × 103/mL; P < 0.05). The in vitro studies demonstrated that most samples were resistant to oxytetracycline. We concluded that the use of intravaginal devices, regardless of their composition, provoked an increase in the normal vaginal bacterial flora, but values returned to pre-insertion numbers by the day of oestrus. According to in vitro results, amoxicillin, ampicillin and streptomycin were the most effective antibiotics to prevent vaginal bacterial growth.

Efficacy of anti-microbial agents on vaginal microorganisms and reproductive performance of synchronized estrus ewes

“…In some laboratories and commercial products manufacturers recommend that to avoid vaginitis and decreases the perceived odour at sponge withdrawal, antibiotics should be added to sponges before insertion to the vagina. Although tetracycline is antibiotic, most widely used in association with sponge treatments, there are several studies reporting that it is the antibiotic with the greatest number of resistant colonies [7,9,10] and this may explain the decrease in conception rates after its application. Others observed the application of gentamycin to vaginal sponges is efficient in preventing vaginal infections provoked by intravaginal sponge [11].…”

Investigation of the Effect of Intravaginal Device-type and Treatment-duration on Vaginal Features in Ewes and Determination of Antibiotic Susceptibility

“…The present study results showed that the use of intravaginal devices increased the bacterial number to them despite being stayed in the vagina for different durations. Manes et al (2013) stated no significant difference between devices' in vagina stay durations in terms of the number of vaginal bacteria. Al-Hamedawi et al (2003) stated some changes in the number of vaginal bacteria as a result of the physical actions exerted by the devices that retained and absorbed vaginal secretions throughout their stay in the vagina.…”

“…types as the most common species in vagina of the ewes. Manes et al (2013) reported that G + bacteria as the dominant colony before insertion of the vaginal devices and Bacillus spp. as the most commonly observed species.…”

Importance of Characterization of the Vaginal Microbiota in Ewes and Nannies

“…This decline in CFU/ ml arises from elimination of the irritant and also from the increase in local immunity response caused by estrogenic phase during proestrus and estrus (Martins et al, 2010). Manes et al (2013) stated that there was no significant difference between the application dates in terms of numbers of vaginal bacteria, however; that the number decreased to the levels before devices were installed on the day estrus were observed. Yeşilmen et al (2008) reported that progesterone had no significant effect on the increase in number of bacteria in vaginal flora and that the number of bacteria also increased in the ewes to which empty sponge was attached.…”

“…They recommended a drug named Ciprofloxacin for treatment of vaginitis caused by Gram positive or Gram negative bacteria. reported Cephalothin and Gentamicin type antibiotics, and Manes et al (2013) reported Amoxicillin, Ampicillin and Streptomycin as the most effective antibiotics in preventing bacterial growth. As Martin et al (2009) included in the study they made only the healthy animals which do not have antimicrobial treatment history, they expected the members of normal vaginal microflora to be rather sensitive to antibiotics that were tested.…”