Theriogenology and Veterinary Reproduction Flashcards

A 6-year-old intact female dog presents with polyuria, polydipsia, and a pendulous abdomen 6 weeks after estrus. Vaginal discharge is absent. The most likely diagnosis is:

Answer: Closed-cervix pyometra

Closed-cervix pyometra presents without vaginal discharge because the cervix remains closed, causing uterine distension with pus and systemic signs such as PU/PD.

Which organism is the most common cause of contagious equine metritis (CEM)?

Answer: Taylorella equigenitalis

Taylorella equigenitalis is the gram-negative obligate pathogen responsible for CEM, a reportable venereal disease causing endometritis and reduced fertility in mares.

In the bull, what scrotal circumference (SC) is the MINIMUM for satisfactory classification under Society for Theriogenology BSE standards for a 24-month-old bull?

Answer: 32 cm

A 24-month-old bull requires a minimum scrotal circumference of 32 cm to meet satisfactory classification, as SC correlates strongly with daily sperm output.

Which stage of parturition in the mare is considered an emergency if it lasts more than 30 minutes?

Answer: Second stage (delivery of foal)

In mares, second-stage labor (expulsion of the foal) should not exceed 20–30 minutes; prolonged second stage risks placental separation and foal hypoxia.

What is the term for the failure of one or both testes to descend into the scrotum in male dogs?

Answer: Cryptorchidism

Cryptorchidism describes the condition in which one (unilateral) or both (bilateral) testes fail to descend into the scrotal sac, predisposing to Sertoli cell tumors.

GnRH given at the time of artificial insemination in cattle is primarily used to:

Answer: Induce ovulation and improve conception rates

GnRH at AI triggers an LH surge that induces ovulation and ensures appropriate follicle rupture, improving conception rates especially in timed-AI programs.

Which breed of dog is most commonly affected by vaginal hyperplasia (vaginal prolapse) during proestrus/estrus?

Answer: Boxer and English Bulldog

Brachycephalic breeds such as Boxers and English Bulldogs are predisposed to vaginal hyperplasia, an estrogen-driven proliferation and eversion of vaginal mucosa during estrus.