Case 20: Artificial insemination in dogs

CASE 20: Artificial insemination in dogs

Case information:

You are presented with a 3 year old intact female Beagle for artificial insemination. The owners are interested in artificial insemination because the male to be used is over 10 years of age and has arthritis, precluding natural service. Below are the vaginal cytology specimens and serum progesterone concentrations over the last week.

The male has never before been used for breeding. You collect 0.5 ml of semen that is cloudy. Total number of spermatozoa in the sample collected is 150 million. Percentage progressively motile spermatozoa is 75%. Morphology shown below is representative of the sample.

Question:

On what date(s) should this bitch be bred?

Answer:

Optimal breeding dates are June 25 and June 27. Serum progesterone concentration suggests ovulation occurred on June 23 (serum progesterone on ovulation day varies from 4-10 ng/ml). Optimal breeding day for fresh or chilled semen is 2 days after ovulation. Conception rate is optimized with two breedings, ideally performed 2 and 4 days after ovulation.

Question:

Do you think this male's semen quality is adequate to effect pregnancy in this bitch?

Answer:

Total number of spermatozoa in the ejaculate is lower than normal (normal = 300 million to 2 billion). Of the three spermatozoa visible above, two are normal, suggesting that 2/3 of the spermatozoa are normal. This would give this dog 2/3 of 150 million, or 100 million normal spermatozoa in every ejaculate. A goal for insemination is to introduce at least 250 million normal spermatozoa into the bitch over her fertile period. That would require three inseminations from this male, assuming the semen quality from this first collection is representative of what he will produce in the future.