Timing of fertile period for successful pregnancy in American Bully dogs

Abstract

Determination of the timing of the estrus cycle is essential for fertile mating. There are physiological variations among breeds, between bitches, and between cycles of the same bitch [1, 2]. If serial monitoring and many tools applied, the exact moment of ovulation could be pinpointed. However, it leads to time and costly difficulties. Progesterone concentrations during estrus cycles follow a specific pattern, and it is largely used in the timing of the fertile period. Although it has a similar pattern in general, it is likely that breed-specific differences exist. The aim of this study was to investigate the way of timing the fertile period of successful pregnancy in American Bully dogs based on vaginal cytology and progesterone assay with minimized cost. To identify the empirical relations among reproductive characteristics, we performed statistical analyses on data from proestrus-to-estrus 27 American Bully dogs referred for 7 months. We found the significant correlations between the cyclic changes of vaginal cytology and progesterone assay. The relationship of serum progesterone concentrations with the days from the vaginal discharge onset was analyzed through linear regression assay. In conclusion, we addressed two standards in the timing fertile period with a minimal number of progesterone assays in the breeding management of American Bully dogs. We were able to provide some reproductive traits of American Bully dogs.