Case 12: Abnormal estrous cycle in a bitch

CASE 12. Abnormal estrous cycle in a bitch

Case Information: You are presented with a 4 year old intact female Samoyed for breeding management. She has been bred at two other heat cycles, to proven males, and has not become pregnant. You see her on the seventh day from the onset of proestrus. Her vulva is swollen and serosanguinous vulvar discharge is present. Her vaginal cytology is as below. Serum progesterone concentration in this day is 1.1 ng/ml.

The owner's male is not interested in the bitch. He waits another three days before bringing her to you again. Her cytology is as below. Serum progesterone concentration on this day is 1.6 ng/ml.

Question:

Did this bitch have a normal estrous cycle?

Answer:

No, she did not. Normal bitches ovulate somewhere from late proestrus to mid-estrus and abruptly go into diestrus six days later. Serum progesterone concentration is 4-10 ng/ml on the day of ovulation and rises after that. This bitch had vaginal cytology indicative of late proestrus when first seen and had diestrus cytology three days later. Her serum progesterone concentration never was high enough to indicate ovulation had occurred. This bitch had an anovulatory cycle and was not fertile.