What’s a Pretty Good Ram?
- Kelley Yates & Sarah Carr
- 18 minutes ago
- 7 min read
By Kelley Yates, Executive Director, Kentucky Sheep and Goat Development Office
Sarah Carr, Ph.D., Assistant Professor, Kentucky State University
Purpose of the Ram
The rams in our operations do not get all the attention they deserve because we use them for a short amount of time each year. However, the rams are the ultimate deal breakers for producers, because 50% of genetics of their offspring come from the ram (and 50% from the ewe). Therefore, rams need to be in our thoughts throughout the entire year. The sole purpose of a ram is to instill his genetics into your flock. Money-making rams are those that can produce either quality replacement females OR pounds of lamb. Therefore, when selecting the best ram for our operation, we have these two goals to choose from to maximize their genetic potential. In a commercial operation, we could ask, “Can a ram produce quality replacement females AND pounds of lamb?” Well, yes he can, but is that truly getting the most out of his genetic potential? This is why, you want to set clear goals to maximize production.
Producing Replacement Females
Seedstock Producers
When we think of quality replacement animals we think of seedstock producers. The goal of a seedstock operation is to consistently replicate quality genetics that exemplify specific traits. Those traits are what lead to different market goals like producing pounds of lamb, parasite resistance, finer wool diameter, etc. For breeding females, we want maternal traits that will allow the females to raise lambs that are heavier at weaning, more parasite resistant, or have fine wool, for example. A ewe’s ability to raise lambs will depend on traits like prolificacy, good mothering ability, milk production, etc. Therefore, when selecting a ram for producing quality replacement females, it is critical to select a ram that would pass on these maternal traits.
Generally, a seedstock producer is going to produce ewes and rams that fit one or two specific traits. You can’t breed for several traits at once and make a difference in any of them; that’s not how genetics works.
In a seedstock operation, you will oftentimes see linebreeding in the mating systems where rams do breed back to their offspring or relatives (not daughters but granddaughters or half-sisters). Over time, a single ram could contribute up to 80-90% of a flock's genetics through this breeding approach. Now think about that. In linebreeding, the goal is to concentrate select high quality genetics, and seedstock producer may have a flock with high percentage of genetics with maternal traits. It is clear that the ram has a significant contribution to the genetic potential of replacement females.
Notice though that in selecting for the maternal traits, traits that promote pounds of lambs such as growth rates, weaning weights, and survival are not as high of a priority on this list. In this scenario, breeding emphasis can be put on maternal traits, but that generally lowers the traits allowing for producing pounds of lamb, and vice versa which is another reason why it is important to focus on a production goal.
Commercial Producers
It is possible for commercial producers to raise their own replacement females. The key is using a mating system that prevents a ram from breeding his closest relatives. Dr. Debra Aaron, University of Kentucky, explains mating systems in Crossbreeding Considerations in Sheep- ASC 224. In this publication, she explains how to use a criss-cross and a three-breed rotational cross system. The criss-cross system would require using at least two different rams each breeding season- one for maternal traits and one for production of lamb. By alternating these traits, you can balance them within your flock, thus creating offspring for both the purpose of producing replacements and pounds of lamb.
Pounds of Lamb
Subsequently in commercial operations, since we are primarily concerned with ewes raising pounds of lamb, we want to mate prolific females to rams with desired performance traits like growth rates, weaning weights, and survival. Therefore, the combination of quality maternal trait ewes on quality carcass trait rams will get us more fast-growing lambs weaned.
In a commercial operation, a ram will contribute half of the genetic influence within a flock in a terminal cross system. In this case, terminal cross systems are optimal because the combination of maternal traits in the females need to be mated with the performance traits of males to produce the kinds of lambs profitable for commercial production.
It is important to note that if replacement females are retained from a terminal sire cross, those females cannot consistently replicate their maternal traits when mated to a performance trait male because the percentage of maternal traits will be more diluted in the offspring. The same is true that a replacement female cannot replicate her performance traits if mated to a maternal trait male. Subsequent matings will result in offspring that are not prolific or produce enough milk to raise fast growing, quality lambs. Therefore, it would be best for all the females in a terminal cross mating system to be sold for slaughter.
As you can see to get the most out of a ram’s genetic potential, his purpose needs to either focus on creating quality replacement females or pounds of lamb.
Number of Rams
Ram power is the superpower. Having an optimum number of rams to service your ewes protects you from seasonal infertility, illness of a ram, loss of a ram, etc. If you think you just need one ram, get two.
Additionally, you may need more than one ram if you are focusing on performance traits, and you want to create your own replacement females. In the criss-cross mating system, you will need two types of rams at each breeding season: one maternal and one performance. The three based system, as discussed by Dr. Aaron (Crossbreeding Considerations in Sheep- ASC 224), requires three rams at each breeding season: one maternal, one performance, and one dual purpose, for example. If you have a large flock, you may need to have more than one of each type in order to service the number of ewes.
Here is the recommended number of rams needed per number of ewes:
Mature Ram: 35-50 ewes
Yearling Ram: 20-35 ewes
Ram Lamb: 15-20 ewes
It is important to note that some factors can greatly change the ratio or rams to ewe recommendations. For example, larger flocks can have a ratio as high as 1:100 or 1:150 for a mature ram. However, if estrus has been synchronized, more rams are needed to efficiently breed all of the ewes because they will all be in heat at the same time. The ratio may be as low as one ram for every 5-10 ewes.
Value of a Ram
Since a ram is a significant portion of the genetics in your flock (50-90%), it is better to get quality instead of inexpensive. An inexpensive ram can cause you a great deal of problems down the line by introducing mediocre traits that do not meet production or breeding goals.
Typically, a purebred ram is going to cost more than a commercial ram because you are purchasing years of genetic influence and reputation. Mating purebred rams to commercial ewes can create high hybrid vigor allowing you to see significant changes more quickly.
Hybrid vigor or heterosis is where cross two different breeds can result in superior genetics than either the dam or the ewe and can be used as an efficient production strategy.
Quality commercial rams should be priced 4-5 times higher than the cost of a slaughter lamb, hence, you see more variation in prices for commercial rams depending on the time of year or overall slaughter market environment.
Purchasing Based on Visual Appraisal
Most of the time you are choosing a ram based on visual appraisal. If you can get more information like birth type, birth weight, weaning weight, 120-day weight, etc., that information can help you better determine if the ram will meet your production goals. Below are things you need to evaluate while you are looking at the animal:
Fertility Indicators
You can evaluate indicators of fertility with a physical inspection. The easiest way to is to analyze the scrotal circumference directly around the scrotum at the largest distance. Testicular and scrotal size is closely related to fertility and in this case, the bigger the better. When visually inspecting the testicles, it is important to also verify that they are symmetrical, and there are no lumps or injury.
Structural Soundness
Once you know that the ram has desired fertility indicators, it is important to determine whether or not he has the structural and physical capacity to do the job by inspecting their feet, legs, and shoulders conformation. It is necessary to ensure they are in good body condition, and their mouths are such that they can eat well enough to keep condition while breeding. Basically, if a ram does not have sound feet, legs, shoulders, and a correct mouth, he won’t last long. You need rams that can move smoothly, mount correctly, and eat feed efficiently.
Environment
Rams have a lot of work to do, and you want to set them up for success. When purchasing, you need to look for a ram that has been raised in an environment similar to yours because a great looking ram who has been on feed most of his life is going to completely fall apart in a pasture-based system. When purchasing a new ram, we must identify the environment they have been in including their state, location, and climate, if they are from a feedlot or pasture, what they have been fed, and their previous exposure to parasites.
When to Replace
When you purchase a ram, you may ask, “How long can I keep him?” Fair question since you are making an investment. Keep your ram as long as he is making genetic improvement, breeding ewes that are the least related to him and meeting production goals. For genetic improvement, remember these tips:
1) Linebreeding should only be used to continue exceptional genetic quality. When males without exceptional genetic quality are mated to his close relatives, he generally creates more problems than improvements.
2) The only true way to know if you are making genetic improvements in your flock is through records which help create benchmarks and goals. Data can then be used to determine if and when a ram is no longer moving the flock towards your market goals.
3) If you start with a mating system plan, you will know at least the minimum amount of time you will keep the ram, barring he is still meeting your expectations. For example, in a terminal cross mating system where all the lambs go to slaughter, you can use a ram until he is no longer serviceable.
Conclusion
The purchase of a ram is the most significant choice you can make in your flock. Marketing goals will establish the type of ram you need, as well as the purpose he will serve in your operation. Creating a solid mating system and production goal prior to purchase will help you get the most out of a ram’s genetic potential, making him a valuable asset.
