By BOB BROWN
This is normally the time of year when you are well into the lambing and kidding season. However, I want to jump ahead and discuss replacement selection, because most of you will be selling lambs and kids off into the spring markets.
You don’t want to sell off animals you should be keeping for replacements because you didn’t incorporate data into a more thoughtful decision making process. Selecting your replacement males and females is one of the most important management decisions that you make.
The decisions you make this year affect the gene pool and genetic improvement of your flock and herd for many years. A wise old man once told me that the most important tool on a livestock farm is a scale to weigh your animals.
I have often tried to refute that, but have never been quite able to do so.
Fencing pliers
Certainly, whoever invented fencing pliers was the Einstein of agriculture. Likewise, there are times I would doubt the quality of life without duct tape.
But, I have to support the fact that a scale is our most important tool. The scale enables us to evaluate rate and efficiency of weight gain.
Performance is the basis of our livestock industry.
There are other important criteria besides weight to consider when selecting which lambs and kids you will keep to enter your flock and herd. You should visually evaluate structural and muscular conformation, correctness of feet and legs, breed characteristics for purebreds and fleece quality for fiber types.
But, how do evaluate rate of gain? Do you simply weigh them and the biggest ones are the best?
The answer would be an emphatic NO!
Starting point
The scale weight only gives you a starting reference point to begin the selection process. If you were to weigh your lambs and kids and simply select the biggest ones in the pen for replacements, you would probably pick a lot of singles born in the first week or two of your birthing season.
Although these may be lambs and kids that look the best (phenotype), these are not necessarily your best offspring genetically.
It is the lambs and kids with the best genetics (genotype) that you want to keep for replacements to improve your flock and herd.
There will be lambs and kids that scale weigh lighter, but when you adjust their weights using the following factors, they will be genetically heavier than those that scale weigh higher.
(Bob Brown is a Penn State Livestock and 4-H Extension Educator in Bucks County. He can be reached at rab37@psu.edu or 215-345-3283.)
