Achieving genetic progress and meeting your production goals depend in large part on selecting the right breeding ram for your flock. No animal has greater influence on genetic progress (or lack thereof) than your breeding ram. Selecting a new sire should be considered an investment in the genetic future of your flock. We all know that the ram provides 50% of his genetics to his offspring and we often hear the phrase that “your ram is half your flock”, so careful selection is important.
For many breeders it all starts with the phenotype. That is, the physical appearance of the animal, but technically it also includes its birth type, rearing type, and various weights and measurements which can be used to evaluate its performance relative to its peers. Just remember that appearance is roughly 80% environment (nutrition) and roughly 20% genetic. In production flocks, structural correctness is important. This is especially true for traits that have direct impact on function and longevity such as a sound feet and legs and a proper bite. And of course, for rams a breeding soundness exam, or at the very least, a basic inspection of his testicles – checking for uniformity in size, their size and firmness, and the presence of lumps – should always be done.
Too many shepherds base their decision on physical appearance alone and overlook even the most basic of production data. Although an emphasis (perhaps an overemphasis) on birth type of the animal is fairly common, a review of the reproductive history of his dam or paternal granddam would be much more informative. Other basic production data can be useful as well. Taking an “old school” approach by calculating 60 day adjusted weaning weights and average daily gains provides a measurement that’s easy to understand and allows direct comparison among lambs. Ask to see the raw data behind any ram you are considering purchasing (or planning to bid on). While you’re at it, ask for the average weights or fecal egg counts, for example, for his entire contemporary group.
Using estimated breeding values (EBVs) to determine which ram is best suited for your flock starts with understanding the strengths and weaknesses among your brood ewes. It’s not realistic to expect one ram to fix all of the limitations in your ewe flock. Rather, an incremental approach is often needed. Starting with your production goals, think about what is most limiting in your flock. What’s holding you back? Is it challenges from parasites on pasture, more rapid growth to market weight, or simply not enough lambs born per ewe? It helps to identify 2 or 3 traits that you think you need to improve on, then review the current NSIP percentile report to see what the range of possible EBVS are and importantly what’s the average EBV (i.e., the 50th percentile) for that trait. By keeping those parameters in mind when you’re perusing a sale catalog or sifting through the data on a series of candidate rams, you’ll be a lot more focused and less distracted by all the other data. The Eastern Alliance has a series of fact sheets that can help you understand what the various EBVs tell you and how to put them to work.
Selecting a ram is one of the most important decisions we make as shepherds. Even more so when we only use one ram per breeding season or plan to expand our ewe flocks by retaining ewe lambs. A thorough review of possible sires for production-oriented flocks should include visual inspection as well as any raw data that the breeder has collected. Finally, NSIP breeders will be happy to share their animal’s latest EBVs to further help you with your decision.
By: Tom Hodgman and Roxanne Newton, EAPK Members