Sheep breeding and cultivation

The Athens disk, ready for tillage.

With only one ewe left to deliver, everyone at The Farm School is eagerly looking forward to the end of this year’s lambing season. We have had a great season so far, though there have been some real complications and challenges.

We are transitioning our sheep flock from Border-Leicester ewes to Dorset, and at the same time, trying to develop a younger profile in the group. Our flock was older and was not genetically strong or well defined, and our production numbers clearly showed that a significant change was called for. We have been culling older ewes for a few years, and last year we started using a Dorset ram from Sweetwater Farm, in Petersham, Massachusetts for breeding. We ended up purchasing the ram last fall, and he came with his larger and more assertive cousin. So both rams, named Dirk and Atticus, by the student-farmers, went in with the ewes on Halloween of last year, and we have been seeing more and larger lambs throughout the season. Dorset sheep are known for their strong breeding abilities and prodigious milk production, and they are the second most popular white-faced sheep in the U.S. behind only the Suffolk. Since we wanted more and larger lambs, these two strengths really appealed to me when I went looking for a new ram.

There are many ways to approach a change in livestock breeds on a farm, with different challenges, costs, risks and benefits to each. The simplest and fastest approach is to sell or slaughter all the animals that you currently have, and replace them with those of the breed you want. This can be difficult if you cannot find a local producer who has the type you’re after, and it can cost a lot to buy good female animals. This approach also opens you up to the danger of unknowingly buying someone else’s unwanted or less-desirable stock, and putting the genetics of your flock in the hands of another farmer. Farmers typically are not eager to sell their best animals, especially if they have been working for years to develop genetics that they really like.

Getting the Flat Field ready for planting.

A second approach to breed transition, called ‘grading up’, is simply to repeatedly match your ewes to a ram or rams of the breed you want to transition to, and replacing the older original ewes with replacement crossbreeds until the whole flock has switched over. This is a slower method, taking several generations, and it gambles on putting most of your genetic eggs in the single basket of that individual male, but it does not require total flock replacement. (The phrase ‘putting all your eggs in one basket’ is peculiar when discussing male breeding stock, but I can’t think of anything clearer.) This transition method can also flirt with line breeding or inbreeding since you are repeatedly breeding ewes to the same ram. If I decide to change breeds, and go out and find and purchase a ram with exactly the genetics that I want, I will be inclined to breed him for several years to ensure that his genetics runs throughout my flock. His daughters will share half of his genetics, and if he breeds them, the offspring will be 3/4, and his great grand-daughters will be 7/8. This type of line-breeding is an effective way to spread the desired genetics in the flock, but it has all the risks inherent in such close breeding, especially if the ram has hidden genetic weaknesses. The solution is to change rams every year or two, buying and selling rams of the same breed as needed, and incurring the added cost, risks and work that comes along.

Finally, a farmer can develop their own genetic lines, keeping ram lambs from their own ewes, and developing several different genetic lines. This multiple-line approach will allow a farmer to avoid inbreeding and line breeding, but will require very specific record keeping and breeding management to ensure that each ewe is bred to a specific ram that has been selected to match her genetic history. This will likely mean using artificial insemination to manage the breeding.

We have had a nice run of warm and dry weather, before today, and we have been able to do some of the initial cultivation in our veggie fields in preparation for the first round of planting. This process begins with pulling all the cultivation equipment up to the shop, checking it all over, ordering and repairing parts as needed, and getting everything into running order. Our fields all dry-down at different rates, depending on soil type and location, and Tyson checks them regularly through the early spring until he decides that the soil can handle the tractor. We also had a chance to spread some manure and grass seed before the rain today, and hopefully that will help get our hay fields growing strong this summer.



Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )


Connecting to %s