Many small flock owners believe

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2 MKING NEW LOODLINES Using the Only Ram You Have CROL J. ELKINS CRITIERHVEN REGISTERED PoLLED RDOS LCKELLY HIR SHEEP Introdution Many small flok owners believe they need to replae their ram every ouple Of years to avoid problems with inbreeding. They may disover, however, that finding a suitable replaement ram is harder than they thought. If they have a good quality flok, it may be hard to find an unrelated ram that is equal to or better than the one they want to replae. Having found a great new ram, they may disover that he doesn't "nik" well with the ewes; their ombined genetis just don't tum out as well as planned. When the ombined genetis do reate great new lambs, the lambs may be surprisingly diffiult to sell. Customers wanting breeding stok or a starter flok may balk when they realize how hard it will be to find unrelated stok within driving distane when it is time for them to expand. If replaing rams every other year might reate as many problems as it does solutions, what are the options? This artile suggests that small flok owners onsider establishing two or more distint bloodlines on their farm. Owners an do this inexpensively using one ram and will end up with animals whose health, purity, and bakground they an feel onfident about while knowing the animals are not too losely related. January/February 2003 My Experiene: Starting Out Small When I aquired my first two ar.bados lakbelly ewes, they already had been bred at their previous owner's loation. I kept their lambs, one ram and one ewe, and thus began my flok of four. It didn't take me long to realize that my breeding options were limited-my ram ould be bred to his mother, but without knowing what good and bad traits suh inbreeding might be intensifying, I was unwilling to risk breeding him to his sister or half-sisters. I purhased an additional two unrelated ewes, but I was still stuk with the limitations of one ram. I thought about getting another ram, but the nearest unrelated polled ram was several thousand miles and several hundred air-freight dollars away. lso, as a newbie to raising sheep, I didn't have spae or pasture to aommodate a separate ram pen, whih I would need if I wanted to be ertain about whih ram had bred my ewes. What to do? Lukily, about that time I read an posted to the Sheep-L listserv that mentioned the merian Livestok reeds Conservany's (LC's) breeding plan for rare and endangered animals. I want to summarize their information in this artile so that it might help other breeders of unommon breeds who are stuk in a "one ram rut." ll information in this artile is liberally and thankfully borrowed from the merian Livestok reeds Conservany's book Conservation reeding Handbook authored by D. Phillip Sponenberg and Carolyn J. Christman (ISN , 136 pp, $12.9 +P&H). You an purhase this book diretly from the LC's Web store at < with my heartiest reommendation. You an ontat the LC at P.O. ox 4 77, Pittsboro, North Carolina 27312, telephone Small Is a Lot Like Rare There are almost 100 breeds of attle, goats, horses, asses, sheep, pigs, and poultry that are in danger of beoming extint. The arbados lakbelly sheep, although not threatened by imminent extintion, is onsidered a "wathed breed" beause there are fewer than 10,000 of them in the world and fewer than 2,00 of them registered annually in North meria. Many of the truly endangered breeds of livestok live in isolated lusters where a single male lives with a few females (the foundation male and females). Intense inbreeding ours as the male, and eventually his sons, breeds with the only available females, whih are all related to him. The LC has developed a breeding program to resue these endangered breeds from extintion. The resue breeding program is designed to inrease the animal ount in 19

3 a breed while also maintaining the bteed's geneti diversity and dereasing its inidene of inbreeding. For the small farmer hoosing to raise an unommon breed of sheep (in my ase arbados lakbelly), a flok of one ram and two or three ewes often resembles one of the "endangered" breeds. There may be no plae lose to obtain replaement livestok or funds to purhase good breeding stok. Without new blood, the flok will beome seriously inbred, reduing the value and vitality of the flok. Therefore, for the purpose of this artile, we will treat the small arbados lakbelly flok as if it were rare and desribe a resue breeding program useful for the small farmer. Step 1-Resue reeding If anything happens to your only ram, your "rare" flok is essentially extint. The goal of a resue program is to develop at least three distint male bloodlines from the original ram and ewes, thus preserving your male line while also reduing inbreeding. eause you have only one ram, it will be the ewes who ontribute most heavily to the geneti diversity in your breeding program. In order to develop three or four distint male bloodlines, you will need to breed your ewes to as many different rams as possible. Sine you have only one ram, you will need to make more. The following paragraphs explain how to do this using a sample flok of one ram and four ewes.* Throughout this artile, alphabeti letters are used to represent eah of the bloodlines in your flok. We start off in this example with ram and four ewes,, C, D, and E. Their offspring are identified by the ombination of letters from the ram and ewe. For example, ram + ewe C=lamb C. Table 1 illustrates the steps using alphabeti letters. s the number of generations inreases, so does the number ofletters used to identify the lambs. I found this to be very omplex and learned that I ould better understand what was going on by referring bak and forth between the text and the table. Hopefully, you will, too. Only the rams, the original ewes, and the ram lambs are listed in the table beause they are the most important members of the resue breeding program. When the daughters enter the breeding program, mate them to whatever ram lamb is sheduled to breed w~th their 20 mother. eause arbados lakbelly sheep will breed at any time throughout the year, you an breed the ewes bak shortly after yiu have weaned their lambs. First breeding yle: reed the foundation ram to all four ewes. Keep the foundation ram until the next generation of rams is ready to breed, then ull him (sell, buther, or transfer to a different breeding program). Keep all of the lambs for the third breeding yle. Seond breeding yle: Do the same thing you did with the first breeding yle beause your foundation ram is still the only ram old enough to be reliably fertile. Keep all of the lambs for the fourth breeding yle. Third breeding yle: Divide the flok into two small breeding groups (this an be a problem when spae is really limited, but it is neessary to at least temporarily ordon off a small area for eah breeding group (using eletri netting or reedln9 Generanon Cyle Ram used First 1 Tgble 1: Resue reeding Program ters are half-sisters of the rams, but as we progress through the resue breeding program, this inbreeding will be redued.) Cull the ram lambs used in this breeding after their offspring are born. lso ull any ram lambs born to the daughters of the foundation ewes in this group. Fourth breeding yle: s you did with the third breeding yle, divide the flok into two breeding groups, exept use the ram lambs from the seond breeding yle, all of the foundation ewes, and all of their daughters from the seond breeding yle. Cull the ram lambs used in this breeding after their offspring are born. lso ull any ram lambs born to the daughters of the foundation ewes in this group. Fifth breeding yle: This breeding yle ontinues to use rarri lambs born from foundation ewes rather than from the daughters of those foundation ewes (whih you should have ulled). This further redues inbreeding and inreases Ewes bred,c,d, E Young rams,e.roduj',d 2, C, D, E C, E unouuo uooo oouooon oooooowoooouoououoouooooooooouoooouuoouooonouu oououoooooooooouoooooououuounuuoouoo ohon oouo onouoou Seond 3 C, D (plus their daughters from the #1 IC breeding yle) D. E (plus their daughters from the'#1 DIE breeding yle} 4 C D. E (plus their daughters from the 112 CID breeding yle) E, C (plus their daughters from the #2 EI... ~~~~~~.~.. ~r.?.~j... Third IC E (plus her daughters from #1, 112, and ~ #3 breeding yles} DIE C (plus her daughters from #1, #2, and ~ #3 breeding yles) CID (plus her daughters from #1, #2, and ~ #3 breeding yles} EI D (plus her daughters from #1, #2, and IMliDQ #3 breeding yles) a) ll offspring of an animal are onsidered to be In the same generation, regardless of the breeding yle they were bom in. b) This model assumes that eah ewe produes one lamb and that half of the lambs bom will be rams. arbados lakbeily regularly produe twins; this will inrease the number of lambs to wori< with but will not speed up the time it takes to omplete five breeding yles. some other temporary fening that is sturdy enough, however, to prevent ram break-throughs). In eah group plae one of the best young rams born from the first breeding yle, two unrelated foundation ewes, and those ewes' daughters from the first breeding yle. (The daugh- *If you don't have four ewes, you an easily modify Table 1 to illustrate a situation with two or three foundation ewes and one ram. geneti diversity. gain, reate a small breeding group for eah of the rams born in the third and fourth breeding yles. Eah ram will be assigned one of the foundation ewes and her daughters from the #l, #2, and #3 breeding yles. (If there are more than four rams available that were born from foundation ewes, reate a separate breeding group for eah ram if you have spae.) The rams that result from this fifth breeding are quarter-brother rams and sheep!

4 only one-fourth the geneti influene of the foundation ram. Genetially, they an be onsidered to be four distint male bloodlines. In as little as three years, you have four rams instead of one, and at least 30 ewes! Eah foundation ewe now has daughters sired by different rams, and eah ewe's bloodline is distint from the other ewes' bloodlines. From a resue perspetive, the flok is no longer genetially endangered and an now progress to a onservation breeding program. Resue RamiD [/C]E [DIE]C [C!OJ [EI]D Table 2: Dividing The Flok Into loodlines Ewes 0 (plus her daughters from the resue breeding program) (plus her daughters from the resue breeding program) E (plus her daughters from the resue breeding program) C (plus her daughters from the resue breeqlng program} Table 3: Conservation reeding Program ment perspetive beause you no longer have to separate breeding groups. Instead, you need only house your rams in one area and your ewes in another. ' In the onservation breeding program, you will breed eah of the rams (from your three or more distint blood-, lines) sequentially to the entire flok of ewes. The following paragraphs desribe how to do this using three of the four bloodlines you established in the resue breeding program. (You an use the fourth bloodline too-or sell it- but it makes this artile too omplex, so I'm New Conservation loodline D(sell} Step 2-Conservation reeding One you have established several distint bloodlines, you an hange from a resue breeding program to a on~ervation breeding program. The goal of a onservation breeding program is to maintain those bloodlines over several breeding yles. The good news is that you an manage the flok as a single unit. This is muh easier from a manageleaving it out!) For simpliity, eah bloodline is assigned a new letter,,, or C, as shown in Table 2. Rather than desribing eah of the breeding yles in detail, have a look at Table 3 and study eah breeding yle arefully. You will see that for eah of the breeding yles, you breed one of the rams to all of the ewes in the flok. ssign an identity to eah lamb born based on its parents' bloodlines. For example, Lambs produed Llnebred reeding (save ewe and ram Llneross Cyle Ram used Ewes bred lambs) (save only awe lambs),,c I,NC 2,,C SI, IC 3,,C C/,C/, I,NC {C/C) C/ ;... ':s:... '... 'Ne:"f.j:..... N, JC (N, NC, NC SI, IC l),,c SI, SIC, N,/C (l, IC, 9/, 9/C I, 9/C, 9/C, SIC Cf, C/8, C/ /C) 6,,C C/,C/, I,NC (C/C, -C/, January/February 2003 SI, SIC C/C, CIS Cf, C/8, C/C. C/C, C/,NC C/C, CfC) beause ram sired all of the lambs in the first breeding yle, the lambs are labeled / (or simply ), /, or /C. Keep all of the female lambs from the breeding yle. Let the rams grow to buthering weight and selet the best /,, or CC ram lamb to use to replae his father. Sell or buther the remaining ram lambs as well as the mature ram (,, or C) beause he has made his geneti ontribution and you an replae him with his son. The ewe lambs from the immediately preeding breeding yle are too young to mate, so keep them separate, probably where you had them during weaning. Labeling the lambs after the seond breeding yle ~an get omplex beause of all of the letters involved. You an simplify things by using this rule of thumb: if a lamb is more than 0% of a line, you an ombine the letters used. For example, the lambs born from the third breeding yle are C/, C/, C/C, C/, and C/C. The C/C lambs are 100% of line C and the C/C lambs are 7% of line C, so you an simply all both groups. t the fourth breeding yle, you return to the line ram, who replaed his father after the first breeding yle. Now, however, he is breeding his sisters as well as his mother, whih alls for a disussion of inbreeding, linebreeding, and linerossing. Inbreeding, Linebreeding, and Linerossing Inbreeding and outrossing (outbreeding) are about breeding animals who are or are not related to eah other. To inbreed is to mate brother to sister, half-brother to half-sister, father to daughter, or mother to son. To outbreed (also o,utross) is to breed animals who are not related in any manner. Clearly, when you mate one ram to all the ewes in a flok, some inbreeding will naturally our. Father/daughter rosses will not happen beause you will retire a ram after breeding so that he never has a hane to breed his daughters. Likewise, there will never be more than one instane per breeding yle of a mother/son breeding. However, brother/sister and half-brother/half-sister matings will be somewhat ommon beause the ram you hoose to replae the line's sire will return to mate his own line 21

5 Table 4: Replaing Sheep y Linebreeding nd Linerossing Line or Llneross l IC 8/C Ewes per Line #of Ewes Soure of Replaements for Eah Line ~, «ll...'.'., -... ~. Total 30 three breeding yles later. Instanes of inbreeding are separated by time (at least three breeding yles), and managed in suh a way as to minimize inbreeding in any one bloodline. In ontrast, linebreeding and linerossing are about bloodlines, not relatives. To linebreed is to mate two sheep who have a ommon anestor but who are little, if at all, related to eah other.. lamb is onsidered line bred if it is more than 0% of a line's geneti makeup. 200% L~ CRC>P To lineross is to mate sheep of different bloodlines. For example, a lamb is onsidered linerossed if it is a mixture of,, and C but no one line ontributes more than 0% of the total geneti makeup. You need to inlude both linebreeding and linerossing in your onservation breeding program. Line bred ewes provide replaements only for their line. Lineross ewes provide replaements for other lines. Table 4 desribes how this replaement sheme works in your flok: The onservation breeding program requires only 30 ewes to adequately represent and maintain three separate bloodlines. This is a reasonable flok size for a small farmer. However, the most powerful aspet of the onservation breeding program is its rotation of rams and their replaement by their sons so that members of the flok-are alternating between an inbred and outbred ondition. This maximizes geneti diversity, strengthens the "good" geneti traits, and breeds out the "bad" geneti traits. The neessity of replaing rams with their sons, however, is the hardest part of this program for most breeders. really good ram, one obtained, is hard to part with, and a breeder is naturally inlined to maximize exposure of that ram to as many ewes through as many breeding yles as is possible, thus "making his good genes go a long way." This approah will work for a short time, but ultimately will leave the breeder in a "one ram rut" and will entail returning to a resue breeding program to one again establish three distint bloodlines. lthough the resue and onservation breeding programs may seem ompliated after reading them through the first time, I enourage you to read them again. Put pen to paper and reate your own breeding tables with the sheep in your flok. If you have spae for a larger flok, read more in LC's Conservation reeding Handbook about managing two parallel floks. Contat the LC with your questions about the resue and onservation bre~ding programs. ut most importantly, think about your responsibility to breed sound, vital, sheep and to strengthen your hosen breed's numbers and geneti diversity. The LC's resue and onservation breeding plan is a great tool to help you ahieve these goals, but the important thing is to have a plan... and to stik with it. Copyright 2002 by Carol J _ Elkiris. For permission to opy, repast, link-to, or redistribute this doument in any way, ontat the author at elkins@ ritterhaven.biz. Carol Elkins owns Written Word, a tehnial ommuniations ompany speializing in doumentation that normal people an understand. During breaks away from her omputer, she steps outside her bak door to wath her flok of registered polled arbados lakbelly sheep froliking in the pasture. For more information about arbados lakbelly sheep or to inquire about sheep for sale, all or . biz Jim & Marge Sheeder Somerset, P (814) sheederpolypays@ftoodeity.net 22 sheep!