# terminal sire - can you explain this to me?



## cathleenc

the line ends here is all I can think of... but can't translate that to breeding. What does 'terminal sire' mean?

thanks!


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## Bearfootfarm

Instead of thinking of "terminal" as an "end", think of it as a "connection"

A "terminal" ram is normally a breed different from your ewes that is used to breed your whole flock to produce crossbreeds with traits that are BETTER than the animals you started with.

Its known as "hybrid vigor" or "heterosis", meaning a crossbreed is likely to get the best traits of both the parent breeds. The "terminal" sire is the one that connects all the lambs to a common set of genes, while the ewes are usually not related

Some breeds are know for being good mothers and having twins or triplets. Other breeds are more known for their muscling and growth rates. 
Take a ewe from the first group and mate it with a ram from the second, and theoretically youll get one that is a good mother, has twins or triplets AND grows fast and produces lots of meat

http://pods.dasnr.okstate.edu/docushare/dsweb/Get/Document-2156/ANSI-3800web.pdf


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## SilverVista

No. Bearfootfarm has described the concept of crossbreeding distinct separate breeds to produce heterosis, but the terminal sire is just that -- the final cross to produce lambs that grow to market grade and yield as quickly as possible. 

The idea of such a breeding program is to pursue maximum efficiency in two areas that don't support one another. The first efficiency is maternal. Ewes are selected from a cross that maximizes hybrid vigor in terms of fertility, fecundity, milk, and ease of birth while requiring lower than average inputs in terms of feed. In other words, the ewes should be prolific easy-keepers. Unfortunately, we know that selecting heavily for maternal traits in animals generally gives up strength in growth and muscling. It's possible to select carefully for a balance of all traits, but if you seek to maximize one end, you give up the other. So the terminal sire comes into play because he contributes the growth, muscling and finishing traits that the lamb crop needs to be more efficient for the market. You wouldn't keep back lambs from this crop because the physical traits inherited from the sire would make them less efficient than their dams as brood stock.


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## cathleenc

so a terminal sire is used as, let's say, step 2 in a cross breeding program? 
Step 1: super mom + super dad = super lambs but probably slow growth, slow ... 
Step 2: super lambs + terminal sire = extraordinary market lambs?

written out it seems clear that I've missed a step between the start and the finish, otherwise why not breed direct from terminal sire and super mom in step 1.

Genetics always require me to put on my thinking cap. Sigh. Need more coffee this morning.

thanks to both of you! I appreciate the tutorial very much.


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## beoircaile

You've almost got it but not quite. Simply put, the idea is to take a hearty breed- like a hill type sheep- with good mothering abilities and cross them with a bigger ram that adds quick frame growth. That gives you faster growing and bigger lambs than you would have gotten originally. Then you take those ewe lambs at 8m (roughly) and cross them with a heavier breed ram to give you fast growing and gaining lambs the following spring.

One of the crosses we are using right now is Shetland ewes crossed with our Bluefaced Leicester ram. For this year, the ewe lambs will be crossed with a Texel cross ram that we have. We'll see how those lambs develop next year and re-evaluate.


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## cathleenc

beoircaile said:


> One of the crosses we are using right now is Shetland ewes crossed with our Bluefaced Leicester ram. For this year, the ewe lambs will be crossed with a Texel cross ram that we have. We'll see how those lambs develop next year and re-evaluate.


Shel,
I read somewhere that shetland crosses still grow slowly.... but perhaps the third generation can escape the small size and slow growth. Do you know of any successful third generation shetland crosses? Would really love to find successful second generation shetland crosses as we just acquired 4 shetland ewe lambs and would love to end up with freezer meat in a single season to feed the family plus wool for me to spin.

thanks!
Cathy


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## beoircaile

We'll be breeding our Shetland BFL crosses that we retain this fall so I'll let you know how they are in the spring. But they didn't grow slowly! By 6m they are about the same size as their dams. I sold a couple that were of substantial size by then. The purebred Shetland lambs were much smaller.

Shetlands aren't a primarily meat breed so you really won't get as much meat from them as you would a Romney or Lincoln lamb. We had 3 yearling lambs butchered this year and the amount of meat that we got back won't last us more than a couple months (but then my kids are almost 6' tall!).

Here's a picture of one of the Shetland BFL ram lamb crosses- at 5 months old he was about 1/2-2/3 the size of his sire.


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## Somerhill

The idea of the British 3 way cross is this:

It starts with a hardy hill breed ewe such as Cheviot, Shetland, Scottish Blackfaced, etc. These are tough, easy lambing sheep with excellent mothering skills,but with smaller, slower growing lambs. The Bluefaced Leicester is a maternal crossing sire. The BFL ram is used on these tough little hill breeds to introduce prolificacy, milking ability, length of loin, rumen capacity, as well as improving fleece quality.
The resulting cross is called a "mule". These mule ewes will have a 200% lambing percentage, and the ability to raise fastgrowing twins on grass while producing a quality wool clip. They are by far the top producing commercial ewe in the UK. Hundreds of thousands of these mules are sold as replacement commercial ewes at huge sales there. 

The final step toward the perfect "butcher's lamb" is by breeding these mules to a terminal sire such as the Brittish Suffolk or Texel. These lambs are all sold for meat, and have the excellent meat carcass from their sire. 

The US Bluefaced Leicester breeders are working hard to explain this system to US commercial shepherds,and things are really starting to take off now as more and more hill breed flocks try a BFL ram to produce a more profitable commercial ewes.

Lisa
www.somerhillfarm.com


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## Maura

On a different note, and a bit picky: hybrid vigor is what you get when two different animals are bred to produce a "better" offspring. A mule results from crossing a jack with a mare. The mule will have the best traits of the horse and the best traits of the donkey, at least in the eye of a human.

Crossing a sheep with a sheep is not a hybrid, it is a cross. Crossing sheep of different varieties does not automaticly give you a better lamb, but it might. It might produce a sheep that is better for butchering, but not better for mothering, or better for fleece. Whoever is deciding which ram is being bred to which ewe needs to understand genetics and what is the intended end result.


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## beoircaile

...being even pickier- the word "hybrid" has two definitions. Hybrid vigor IS the same as heterosis or the enhancement you get by outbreeding. It is used to refer crosses of different lines or breeds within a species.

Most corn is hybrid. The new hybrids out produce the original parent strains.

And a mating of different genera creates a hybrid- in the example that you gave.

So- we're both right. I like win-win definitions!

And you are definitely right, the person doing the breeding really should have an understanding of genetics before they start making breeding decisions.


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## wendle

This page give a little better explanation of a terminal sire, and the mule. 

mulesheep.com


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## beoircaile

It's just a different kind of mule than what Maura described.


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## cathleenc

anyone ever hear of - or try - crossing tunis with shetland? Curious as to what the results might be, both have great mothering/multiple easy births/excellent tasting meat. Good wool. Tunis grow more quickly, not so seasonal in birthing patterns.


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## Liese

Don't the ewes start having lambing difficulties being bred to larger rams? I ask out of curiousity only.


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## beoircaile

They can if you aren't careful about the crosses. That's where the genetic knowledge is needed. You don't want a terminal sire that is too large or throws very large lambs. You want one that has a more narrow head, not big and blocky, and has narrow shoulders. The "money" cuts are in the rear, so you want a sire that has lambs that develop large hindquarters.

It takes management and knowledge of the animals involved.


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## Somerhill

Liese said:


> Don't the ewes start having lambing difficulties being bred to larger rams? I ask out of curiousity only.


That is one of the concerns we had when looking for a breed to cross on our Border Cheviots back in the late 80's. Most the research then showed that you could safely breed a larger breed ram to a smaller breed ewe so long as the weight difference in the mature animal was 100# or less. The logic is that the body size of the ewe to a certain extent controls the size of the fetus.
We decided upon the BFL to use in our cross because of its growth rate, milking ability and wool qualities. The resulting crossbred lambs weighed about 9-10# at birth for twins. (For comparison, the purebred Cheviot lambs averaged 7-9# for twins.) The beauty of the BFL is that its lambs are born very long and narrow, with long narrow heads. Therefore, there are no big foreheads or wide shoulders to hang up in the birth canal. We bred around 50 Cheviots to different BFL rams for several years, and had no more lambing difficulties than in the purebred Cheviot lambs. 
We bred the Cheviot mules to a medium sized wether type (as opposed the the frame type) Suffolk ram, and those brockle faced lambs were just lovely and sold well at auction.

Lisa at Somerhill
www.somerhillfarm.com

p.s. - Thanks, Wendel,for posting that link to mulesheep.com I usually mention that link when talking about mules -the link is on my website.  
Also, more info on BFLs at 
http://www.bflsheep.com 
http://www.bflba.com
These are the breed registry and promotional association websites.


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## FreeRanger

BAck the original question *terminal sire * really means end of the breeding line. Lambs from a "terminal sire" mating are *ALL *turned into meat. *None* of the lambs are are kept for breeding. If any  of the lambs are kept for breeding then you do not have a terminal sire mating, it's that simple.

As stated, this is when a ram is used on a ewe to make the off spring more valuable for meat. By definition "replacement ewes" could never come from a terminial sire mating because then it would not be terminal.....


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## Liese

Thanks Shel & Lisa, appreciate the education


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## roadrunner347

I've got a probably weird question. I have hair sheep. A Royal White is a breed from two different Hair sheep breeds. Dorper rams and St. Croix ewes. Would you get the same results using Dorper ewes and St. Croix rams?


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## baileysclublamb

I have to disagree with FreeRanger.... I raise Club lambs, Many people consider clublambs a terminal sheep. We breed our ewes to the most "terminal" ram we can to get extreme lambs, and keep the most extreme ewe lambs for breeding. We choose our ewe lamb replacements almost completely on extreme conformation, not maternal traits, and have very productive ewes with mostly twins. Yes, we don't have a ton of triplets, but lots of twins.


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## hastyreply

roadrunner347 said:


> I've got a probably weird question. I have hair sheep. A Royal White is a breed from two different Hair sheep breeds. Dorper rams and St. Croix ewes. Would you get the same results using Dorper ewes and St. Croix rams?



I believe the original cross was dorper ram on large frame St Croix ewes. After that they culled the characteristics they didn't want they would cross back in the ones they did. This goes on for many generations until there is a uniformity in the lamb crop. So it's not just a simple cross. You can't cross dorper ram on St Croix ewes and call them Royal white. The main reason they used St Croix ewes is they wanted the mothering ability of the St Croix. They are tougher moms with very little lambing problems. 

I have St Croix/Dorper crosses. There is probably some Royal White back there. This year I bought a St Croix ram to cross on them to get more St Croix back in them. I'll see what I get and how I like it. I am trying to breed some ewes from this cross. I like the badger faces that pop up in the St Croix even though they have tried to eradicate it for years. This is a grandmother and granddaughter. The one in between all white but she's produced color. I don't have enough ewes to cull ruthlessly yet. I may loose color as well with the St Croix ram but time will tell.


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## bergere

The original post was dug up from 2007, so some of the folks that posted years ago, might not be around to answer.


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