This month on Grazing with Cam, we took a closer look at ram selection and how choosing the right genetics can shape flock performance for years to come. We covered considerations for selecting rams for solar grazing operations, including site needs, genetic selection tools, and establishing clear selection criteria.
What Is Ram Selection?
Ram selection is a long-term flock management decision that can influence flock composition and performance for the next 4–5 years. For solar grazing operations, the goal is generally to prioritize functional, low-intervention productivity rather than simply maximizing lamb output. Without clearly defined breeding goals, ram selection can lead to gradual flock drift rather than meaningful genetic improvement.
What Performance Traits Matter for Solar Grazing?
Several traits can be particularly important when selecting rams for solar grazing systems. Parasite resistance is a high priority across regions and can be an indicator of broader immunological fitness. Seasonality is also important for operations using aseasonal or fall lambing programs, making rams with stronger out-of-season cycling genetics valuable. Structural soundness—including teeth, feet, and other indicators of longevity—can help select for a longer productive lifespan. Fertility is another key consideration, as tighter conception windows can reduce labor and make health management and marketing more efficient.
How Should You Match Rams to Your Production Goals?
Ram selection should begin with clearly defining the market and production system. For example, if lambs are sold at 60 pounds, weaning weight may be the most important economic measure, while additional post-weaning growth may add costs without increasing revenue. Prolificacy should also match the production system. Pasture lambing on solar sites may favor single- and twin-bearing ewes rather than extremely prolific animals. Selection should be based on genetic data and defined goals rather than anecdotes; for example, a ram being born as a twin does not reliably predict his genetic contribution to litter size.
How Can Data and EBVs Help?
The National Sheep Improvement Program (NSIP) tracks a range of traits that can help producers make more informed selection decisions, including birth weight, maternal weaning weight, weaning weight, post-weaning weight, eye muscle depth, fat depth, fecal egg count, scrotal circumference, number lambs born (NLB), and number lambs weaned (NLW). Scrotal circumference EBVs can be particularly useful because they are associated with earlier puberty and improved fertility in daughters, but this trait remains underused by many producers. Understanding heritability is also important: reproductive traits are approximately 10% heritable, while growth traits generally have moderate to high heritability. This means producers should have realistic expectations about how quickly different traits can change through selection.
How Should Producers Set and Measure Breeding Goals?
Successful genetic improvement starts with specific goals and a way to measure progress. Producers can establish improvement targets over 1-, 5-, and 10-year timeframes and consider having an outside person review flock records to identify opportunities for improvement. Extension enterprise budget templates, including resources from Missouri and Maryland Extension, can also provide an accessible starting point for tracking flock performance and economics.
What Are the Benefits of Crossbreeding?
Crossbreeding can increase production efficiency, including improving the weight of lamb weaned per ewe exposed. The larger flock sizes often associated with solar grazing operations may also make two-tier crossbreeding programs more practical from a management standpoint. However, successful crossbreeding still depends on the quality of the purebred genetics being used. Elite crossbred animals require elite purebreds—the purpose of crossbreeding is to amplify genetic quality and capture complementary traits, not to compensate for poor genetic selection.