PSIV-17 Impact of vaginitis on a 14-day implant synchronization protocol and its effect on pregnancy rates in beef cattle.

Abstract Previous research on the effect of progesterone (P4) intervaginal implant cleanliness after removal using a 7-day synchronization protocol has shown no effect on pregnancy (Dias, W 2022). As the protocol becomes longer, there is an increasing concern about how much the implant could generate local inflammation and potentially decrease fertility in cattle. However, there is a lack of information regarding the use of a 14-day synchronization protocol and the effect of implant cleaning at removal on pregnancy rates. The objective of this study was to evaluate the effects of the cleanliness of the implant when using a 14-day CIDR (7&7) synchronization protocol on pregnancy rates. We hypothesized that cows with a higher CIDR score (3 or 4) would have a lower likelihood of pregnancy compared to those with a score of 1 or 2. Angus-crossed cows (n=133) across 2 farms were enrolled in a 7&7 co-synch protocol (Anderson et. al. 2021). Implants were inserted according to the manufacturer’s recommendations, with the applicators cleaned between animals. On day-14 the implant was withdrawn and a score, 1 through 4 was given by visually examining the implant. The classification was: 1 = no mucus, 2 = clear mucus, 3 = cloudy mucus, 4 = yellow or red/bloody mucus. Ultrasonography was performed 32 days after artificial insemination for pregnancy diagnosis, and cows were divided into groups, pregnant (n=84 and open (n=49). The open cows’ score average (3.06 ± 0.07) was numerically higher than the pregnant cows (2.95 ± 0.07) but there was no significant statistical difference (p = 0.3712). A high percentage of cows presented a score 3 (75.1%) and 4 (14.2%), which implies that even when following the manufacture’s instructions, mild vaginitis is likely to happen, in conclusion, this study shows that there is no effect of vaginitis on pregnancy status when undergoing a 14-day synchronization protocol. More analysis needs to be performed to evaluate the effect of the circulation hormonal concentration among scores and statuses.