Breeding Soundness in Rams
The Importance of Breeding Soundness Examinations in Rams
Why is it important?
A breeding soundness examination (BSE) is a very important tool to help identify rams that are fit to perform during the breeding season, those that should be treated for disease prior to the breeding season, and those that should be culled. Ideally, the BSE should be performed at least 60 days before breeding is intended to start. The 60 day period allows enough time for treatment of diseased rams, finding replacement rams, and is the amount of time it takes for semen to be produced.
What is involved?
A good BSE entails a full physical examination of the ram, body condition scoring, and detailed examination of the genitalia including testicular measurements. BSEs should also include semen evaluation and blood tests for common infectious diseases. Though done less frequently, an ultrasound of the testicles and associated structures can help to better identify the cause of abnormalities in this area. Additionally, a serving capacity test, also done less frequently, can help to predict pregnancy rates and lamb crop size as the higher the serving capacity of the ram, the higher the pregnancy rates, lamb crop, and weaning weights.
The numbers
When asked, farmers in a Spanish study reported that they believed their ram(s) only had an average of a 19% chance of failure of a BSE. In reality, this study found extreme variabilities between farms with chances of failure between 0 and 85%. The researchers classified 17% of rams as unsuitable to breed and 60% of rams had mild (43%) or severe abnormalities (17%) on physical examination.
An American study of over 14,000 rams failed 29% of the rams, which was similar to findings in studies carried out elsewhere.
The most common reasons rams fail BSEs are substandard semen parameters, genital abnormalities, and decreased body condition scores (BCS). Consistently the research has found that the older the ram and the lower the ram’s BCS, the more likely he would be to not only fail a BSE but the more likely he is to have a physical abnormality or disease, and poor semen quality Epididymitis occurs more commonly in ram lambs and shearlings, most likely due homosexual behaviour leading to transmission of ascending bacterial infections when young rams are housed together.
Why call the vet?
Besides low BCS as a cause of subfertility in rams, the other causes such as semen quality and genital abnormalities, are not typically easily discernible to a shepherd. Getting a veterinarian involved to complete BSEs on all new and old rams, including ram lambs intended to be added to the breeding flock, can lead to higher pregnancy rates, an earlier lambing season, more lambs on the ground, and higher weaning weights.
If you have any further questions
about Breeding Soundness in Rams,
or would like information about a more complete
Flock Health Plan,
please call or email the office
at 705-722-3232 and info@centralontariovet.com
For more helpful resources, check out our Small Ruminant News and Small Ruminants Flock & Herd Health Plans pages.