info:ar-repo/semantics/artículo
Changes in the vaginal microbiota in ewes after insertion of intravaginal sponges at different stages of the oestrous cycle
Date
2018Author
Manes, Jorgelina
Fiorentino, María Andrea
San Martino, Silvina
Ungerfeld, Rodolfo
Abstract
The aims of this study were to determine if the ewe’ vaginal bacterial load differs according to the stage of the
oestrous cycle; and thus, if the stage of the oestrous cycle when intravaginal sponges (IS) used for oestrous
synchronisation are inserted influences the vaginal bacterial biota present at sponge withdrawal. During the
breeding season, 45 Texel ewes were detected in oestrus and randomly allocated to one of three treatments of 15
ewes each according to the stage of the oestrous cycle when the IS were inserted. Intravaginal sponges were
inserted: the day of oestrus (GOes), or 2 (GMet) or 8 (GDie) days after oestrus. Samples for bacterial analysis
were collected the day of IS insertion (Day 0), at sponge withdrawal (Day 12), 24 h (Day 13) and 48 h (Day 14)
after sponge withdrawal. Vaginal bacteria amount increased at sponge withdrawal in all treatment (p<0.0001).
The number of different types of colonies was greater in GMet group than in GDie at sponge insertion (p<0.05),
without difference with GOes. At sponge insertion, the presence of Staphylococcus spp. was greater in GMet than
in GOe and GDi (p<0.05); the presence of Trueperella pyogenes and Haemophilus somni was greater after sponge
withdrawal than before sponge insertion (p<0.001), but without difference between days 12, 13 and 14.
Overall, we concluded that in ewes the normal vaginal bacterial load differs according to the stage of the
oestrous cycle. The continuous presence of the IS homogenised the vaginal bacterial microbiota at withdrawal,
with only slight and transient differences observed on day 13.