# Efficiency of a Modified Ovulation Synchronization Program in the Treatment of Ovarian Cysts in Dairy Cattle

## TL;DR

A modified synchronization protocol effectively treats ovarian cysts in dairy cows without needing to distinguish cyst types.

## Contribution

A modified ovsynch protocol is shown to be effective for treating ovarian cysts without requiring differentiation between cyst types.

## Key findings

- Cyst recovery was confirmed in 88% of cows treated with the modified protocol.
- Cyst size was the only factor negatively affecting recovery, according to logistic regression analysis.
- The protocol allows for timed artificial insemination and is practical for field use.

## Abstract

In dairy cattle, ovarian cysts represent a serious dysfunction of the ovaries. Thin-walled follicular cysts and luteinized cysts exhibiting thicker walls are described. The diagnosis is based on examination by ultrasound and serum or milk progesterone analysis. For a practitioner, therapies without differentiating cysts would be warranted. Therefore, the effectiveness of a modified ovsynch protocol in which differentiation was not needed was evaluated. Fourteen days after treatment, cyst recovery was confirmed in >88% of the cows treated. The median calving-to-conception interval was 95 d. A logistic regression analysis revealed that only larger cyst sizes negatively influenced cyst regression. The modified ovsynch protocol is a useful, practical option for treating ovarian cysts with the advantage of not needing to differentiate between the two cyst types. It can be applied under field conditions and allows for the possibility of timed artificial insemination.

In dairy cattle, ovarian cysts (COFs) represent a major cause of infertility. They can be divided morphologically into follicular and luteal cysts based on their wall thickness, which can be examined by ultrasound, and progesterone secretion, which can be analyzed in serum or milk. The aim of our study was to evaluate cyst recovery using a modified ovsynch protocol with no need to differentiate COFs. Additionally, the beta-hydroxybutyric acid level (BHB), progesterone values, and trace elements in the serum were measured when therapy started. Fourteen days after treatment, COF recovery was confirmed in 88% of the cases. The median calving-to-conception interval, number of artificial inseminations until pregnancy, and median number of days from treatment to pregnancy were not different between the modified ovsynch protocol group and all other COF treatments. The logistic regression for COF included the parameters group, the cyst type, breed, the number of artificial inseminations (AIs), calving to conception cut at 200 d p.p., the cyst size, and therapy. The backward (and also forward) variable selection of the logistic regression yielded only the cyst size as a significant negative impact factor for recovery. In conclusion, the modified ovsynch protocol is a useful, practical option for COF treatment with the advantage of not needing to differentiate between the two cyst types.