Bull Breeding Soundness Exam
What it is:
• Non-invasive exam of bull to determine fertility
• Aspects considered in exam are as follows
• Physical/General Health – Eyes, Heart, Lungs, Soundness (Feet and Legs)
• Palpation of Accessory Sex Glands
• Palpation and measurement of testes
• Collection and examination of semen for motility and morphology with a phase contrast microscope
• Does NOT assess libido of bull
• With a bull playing 50% of the equation in a breeding season it is a financial hardship if he is unable to impregnate cows. Testing bulls will assure that they are able to adequately perform their job.
• Determine if bull is fertile
• Save time, money and frustration if you wait to find out a bull is bad after a poor calving season
How does it work?
A complete bull breeding soundness exam is quite possibly the most effective management tool that a producer can implement to increase pregnancy rates and produce more calves faster. A bull with impaired fertility can cost breeders time, money, and in extreme cases an entire calf/lamb crop. The risk of this can be diminished with routine screening of all breeding bulls before the breeding season.
Decreased fertility or serving capacity of bull can lead to lower conception rates and pregnancy rates in affected flocks and herds. A complete breeding soundness exam 30-60 days prior to the breeding season can alert producers to problems with the male and prevent substantial pregnancy loss due to bull fertility problems.
Complete Breeding Soundness Exams include the following:
Brief physical exam
Scrotal circumference measurement (this is directly correlated with # of sperm produced)
Palpation of prostate, vesicular gland etc.
Semen evaluation using phase contrast microscopy
What is Phase Contrast and why is it important?
Sperm cells (spermatozoa) are microscopic; they must be examined under a microscope. Regular light microscopes have some degree of light refraction, which makes examination of membrane edges very difficult. The anatomy of the head of the spermatozoa (acrosome) and the appearance of the nuclear material within the head are very important in predicting the fertility of that bull. Using a phase contrast microscope one can clearly pick up most acrosomal and nuclear irregularities on spermatozoa. Unfortunately a regular light microscope commonly used does a poor job picking up these defects, we at VHHMS strive to do the bestand have gone the extra lengths to do so. This is important to note. The acrosomal and nuclear material defects are highly correlated to fertility performance in the bull. Phase contrast will pull out about 8-10% of bulls for being unsatisfactory that would be called satisfactory using regular light microscopes.
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