Retrospective Evaluation of Breeding Management Data and Breeding Type and Correlation with Successful Breeding of Bitches

Abstract
Data were retrieved from medical records for breeding management of 576 dogs of 88 breeds. Pregnancy rate was highest with natural service and with surgical insemination with either chilled or frozen semen. Pregnancy rate was lower for vaginal insemination with any type of semen. Age of the bitch at the time of breeding was associated overall with success, with younger bitches (4.4 ± 1.7 years) more likely to be successfully bred than older bitches (5.2 ± 1.7 years) (p=0.04). For all semen types, litter size was significantly greater with surgical insemination than with vaginal insemination (p=0.0004). Serum progesterone concentration on the day of the luteinizing hormone (LH) surge was 3.1 ± 1.0 ng/ml, with a range of 1.3 to 6.2 ng/ml (n = 63). In general, a lower progesterone concentration was associated with success when using fresh semen and a higher progesterone concentration was associated with success when using frozen semen. This was a directed study project for a senior veterinary student. Collecting these data and talking through how the cases had been managed and significance of the findings were excellent learning opportunities for this student. [...]