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Dairy and AnimState University, The Western ureein Livestocx.sociation, Oregon Purebred Sheep Breeder's,Oregon Wool Growers Association.

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• • •

HARRY A. LINDGREN

Oregon lost a great friend of agriculture withthe death last January of Harry Arthur Lindgren.However, his pioneer work for the livestock in-dustry is as much alive as though he were sittinghere with us today.

As is true with any sound education, the foun-dation and growth of ideas and ideals are not lim-ited by one lifetime. Harry Lindgren knew thathis aspirations for our livestock industry wouldbest endure if woven into the structure of soundorganizations.

For 42 years he pursued this goal of helpingto create and strengthen Oregon livestock associ-ations devoted to self-help through education.

Harry Lindgren foresaw the present days ofopportunity for Oregon stockmen to expand andfill the needs of a west coast population boom. Hiswritings and teachings encouraged the industryto prepare for expansion.

His early experience as first superintendent ofOregon State University's branch experiment sta-tion at Astoria instilled the conviction that prep-aration and growth of the livestock industryshould be based on fact and sound research. His40 years (1920-1960) as Animal HusbandrySpecialist for the OSU Agricultural ExtensionService were dedicated to teaching, organizing,and re-teaching.

Rural meeting halls, livestock rings, andrancher's back porches were his classrooms. Thewhole state was his campus.

Contents

Page

Pasteurellosis in Sheep . 5

Anthelmintics for Controlling Sheep Parasites 7

Effects of Inbreeding on Performance Traitsin Suffolks . . . 10

Development of a Sheep for Western Oregon . 12

Responses Obtained from Selecting forTraits of Economic Importance . 14

Problems Encountered in Lamb Slaughter . 20

Lamb and the Trend Toward Greater Meatiness 22

Lamb Carcass Contests . 24

New Methods in Wool Marketing . . 27

4

Pasteurellosis in Sheep

DEAN H. SMITH, D.V.M.

Veterinary Diagnostic LaboratoryOregon State University

Pasteurellosis is an infection char-acterized by widespread capillary hem-orrhage. Septicemias or blood infec-tions can be produced by many differ-ent species of bacteria. However, hem-orrhagic septicemia is a term almostuniversally accepted as indicating aninfection with pasteurella organisms.It is a disease of world-wide economicimportance.

Pasteurella infection is the mostcommon cause of pneumonia in sheepand most often develops followingsome form of stress such as that aris-ing from shipping or from a suddensevere weather change. The disease ismost often seen in feeder lambs butmay occur in mature sheep. Acutecases usually show multiple hemor-rhages. More advanced cases developpneumonia, pleurisy, and inflamma-tion involving the heart and joints.

The infection occurs in other speciesof animals and produces a similar typeof disease. It is quite host-specific inthat it seldom spreads from one spe-cies of animal to another. However,disease can sometimes be introducedinto another species by injection of pas-teurella organisms. Pasteurellosis cancause respiratory infections in humansbut is more commonly found in woundinfections and abscesses.

The disease is thought to be causedby a small microorganism of the pas-teurella group. This group of organ-isms has the property of taking onstains more deeply at the ends than inthe middle, giving rise to the term

bipolar. These organisms are rathereasily destroyed by heat and germi-cides but can remain infective in ma-nure and dead animals for some time.Two organisms in the pasteurellagroup are involved in hemorrhagic sep-ticemia in sheep. Pasteurella multocidais more often responsible for out-breaks of the septicemic form of thedisease and for pneumonia in feederlambs recently shipped. The diseaseusually strikes within two weeks fol-lowing shipment. Pasteurella hemoly-tica is more prevalent in suckling lambsand breeding sheep that have beenthrough some form of stress such asbeing chilled or fatigued. Marsh de-scribes an outbreak occurring when aflock had to swim an irrigation ditch toand from pasture. The infection endedwhen this practice was corrected.

Many scientists believe these organ-isms live in the upper respiratory tractand cause trouble only when body de-fenses have been broken down. This issubstantiated by the fact that the or-ganisms can be isolated from appar-ently normal animals.

One or more viruses are probablyinvolved in this complex disease. Manyoutbreaks occur with typical historyand symptoms, and pasteurella organ-isms cannot be isolated in sheep. Viralagents have been isolated from ship-ping fever in cattle, and there is noreason to assume that they do notoccur in sheep.

In an acute outbreak, affected ani-mals appear depressed and stand with

drooping ears. They refuse to eat andsoon appear gaunt. There is usually arather thick discharge from the eyesand nose and considerable coughingmay be noted. Temperatures rangefrom 104° to 107° F., and the respira-tion and pulse are increased. Lamenessoccurs later if the joints are involved.An encephalitis sometimes occurs whenthe infection involves the brain. Earlyin an outbreak death will usually occurin one or two days. Later, most ani-mals survive for a week or more. It isnot unusual for half the flock to getsick but for only about 10% to die.The pneumonic form develops in ani-mals that live longer. If the factorcausing stress is removed, the outbreakusually subsides in a week or two.

Three forms of the disease havebeen observed. The acute form pro-duces hemorrhages, the subacute abronchopneumonia, and the chronic apleuropneumonia. One may progressto the other.

In the early stages of an outbreak,hemorrhages occur over the heart, theheart sac, the nose, throat, and some-times the stomach and intestine. Laterthe disease seems to localize in thelungs, producing a rather typical pneu-monia involving their lower portions.After this stage a painful pleurisy maydevelop, and the lining of the lungsmay adhere to the rib cage. If thishappens, there is usually a thick graypus present in the lung cavity. If theanimal survives, lung abscesses mayform. The liver may be spotted withvery small white abscesses. The Mon-tana Agricultural Experiment Stationreports that pasteurella organisms area very common cause of a serious formof ewe mastitis called blue-bag. It may

involve one ewe or a number in a flock.The udder is almost always lost anddeath often results.

Many errors are made in diagnosingthis disease. Poisoning from a numberof plants can produce hemorrhagesthat are similar to those seen in pas-teurellosis. A few of these plants arewild cherry, milkweed, death camas,and sneezeweed. Poisoning due to ar-senic, copper, or lead also can looksimilar. Anthrax and enterotoxemiaare sometimes confused with pasteurel-losis. Anthrax can be differentiated bydark blood, swollen spleen, and cul-tural means used at laboratories. En-terotoxemia occurs in animals on fullfeed and has no relation to shipping orexposure. Laboratory methods can beused to identify this disease, also.

The final diagnosis depends on iso-lation and identification of the pasteur-ella organism from the tissues of thediseased animal.

The most important part of treat-ment is good nursing. Affected ani-mals should be well bedded, protectedfrom the elements, and fed a goodquality feed. Serum is available fortreatment and may be effective in theearly stages. It is useless later if pneu-monia has developed. Broad-spectrumantibiotics and sulfa drugs are some-times effective.

Good nutrition, good housing, andadequate ventilation are most impor-tant in preventing pasteurellosis. Ifbacterins are to be used, they shouldbe given 2 weeks prior to shipment andnever while animals are in transit orduring an outbreak. Breeding animalsand show stock sometimes are vaccin-ated annually.

6

Anthelmintics for Controlling Sheep Parasites

S. E. KNAPPDepartment of Veterinary Medicine

Oregon State University

Occasionally, newspapers, agricul-tural journals, and other news mediacontain articles describing the develop-ment of a few anthelmintic (wormremedy). Usually this type of newsrelease describes the effectiveness of amaterial against specific groups of par-asites and also implies that it has beentested extensively by different groupsof scientists within the company re-sponsible for its development and byvarious outside agencies. Since thereis an incessant demand for better an-thelmintics, appearance of these arti-cles frequently stimulates considerableinterest and a number of requests forfurther information. The basic ques-tion concerns how soon the materialwill be available, followed by howmuch it will cost and how effective itis. Because of this situation, it may beinteresting to review what has beenaccomplished regarding the develop-ment of anthelmintic parasite controlin sheep, and to consider some of thefactors concerning the release of newdrugs.

Most people who raise sheep havebeen faced with problems of parasitecontrol. The usual approach when suchproblems occur is to treat the flockwith an anthelmintic suitable for thetype of parasite that is present. Thistreatment may follow a severe out-break of parasitism or be applied oneor several times during the year as ameans of preventing parasite buildupin a flock. The general categories ofsheep parasites which we attempt to

control with anthelmintics and thedrugs used in each case are: gastroin-testinal nematodes—phenothiazine, cop-per sulfate, tetrachlorethylene; lung-worms—emetine compounds, Dicty-cide, iodine compounds ; liver fluke—carbon tetrachloride, hexachlorethane ;tapeworm—lead arsenate, other arsen-ical compounds, and nicotine sulfate.

Before 1946 all but two of thesedrugs were available. Certainly less re-search was being done in developingnew compounds and the demand foreffective anthelmintics was not as greatas it is today. Also, until 1946 the Foodand Drug Administration did not en-force rigid testing requirements beforethe release of new anthelmintics.

Phenothiazine, first used as an in-secticide in 1934 and as an anthelmin-tic for controlling swine parasites in1938, was found to be effective againstsheep nematodes in 1939. Since 1939over 400 reports have been publishedinvolving its use in controlling sheepparasites, and approximately 1,600papers are available concerning pheno-thiazine as either an anthelmintic orinsecticide. Likewise, numerous re-ports have been published on the effec-tiveness of carbon tetrachloride againstliver fluke, and on copper sulfate-nicotine sulfate mixtures for removingstomach worms and tapeworms.

After World War II ended and thedemand for human medicines had beenmet, many chemical and pharmaceu-tical companies enlarged their researchand development activities to encom-

pass the problem of finding new ma-terials for controlling animal parasites.Part of this approach must have beenstimulated by recognition of a needfor more effective anthelmintics thanthose then available. Also, there waspressing need for compounds with abroad spectrum of activity, i.e., againsta wide range of parasites such as thegastrointestinal nematodes. In anyevent, the criteria for development ofnew anthelmintics were that they behighly effective, safe to handle, easy toadminister, and reasonable in cost. Agreat stimulus for new research re-sulted from the application of organicphosphate chemicals to parasite con-trol. These had been developed by theGermans during the war and originallywere intended for chemical warfare. Anumber of testing programs were ini-tiated to evaluate practical methods fortheir use.

Between 1946 and 1961 over 350publications appeared regarding thetesting of drugs for control of para-sites in sheep. To illustrate how thistype of research has been intensifying,53% of these reports involve workdone since 1957. From 1946 to 1957published anthelmintic studies averaged14 papers per year, and since 1957, theaverage has been 34. Furthermore,29% of the publications have involvedphenothiazine, 52% of all publicationsconcerned attempts to control nema-todes, and 19%, 15%, and 14% cov-ered flukes, lungworms, and tapewormsrespectively. At least 58 different com-pounds have been reported during this16-year period. Omitted from thesedata are the thousands of compoundsthat have been screened by differentdrug companies in their efforts to dis-cover effective materials with practicalcharacteristics. It is somewhat f rus-trating to learn that from this total ef-

fort only two compounds of recog-nized significance have been added tothe list of commercial anthelmintics.One of these is Dictycide for controlof lungworm and the other is hexa-chlorethane for liver fluke, which wasreported in 1946. Deleted from thislist are the mixtures or new combina-tions of old materials, which also re-ceived a certain amount of publicity atdifferent times.

After considering these figures, anatural question is, "What does thismean?" Why the recent increase inpublication? What about the news re-leases mentioning promising newdrugs ? What are the restrictions im-posed on the release of newly devel-oped anthelmintics ? Why so manypublications on phenothiazine? Afterall this research, are any new materialsabout to become available?

Several new compounds reportedsince 1957 may be approved in thenext 12 to 18 months, although any ef-fort to forecast such events is purelyspeculative. Two new materials are or-ganic phosphate compounds having anefficacy primarily against stomach andintestinal parasites. Compounds havingsimilar chemical properties and pro-duced by the same companies alreadyhave been approved for use againstcattle grubs. Two other chemicals de-veloped by United States drug com-panies show equal promise but un-doubtedly will have to be extensivelyfield-tested before they can gain ap-proval by the Food and Drug Admin-istration. The British, who apparentlyare not as strict as we are in permit-ting the use of new anthelmintics, haveproduced three new chemicals since1957. All are effective against gastro-intestinal nematodes and have beentested in this country. During the past12 months, three new compounds have

8

been reported effective against liverfluke. A number of new and perhapshighly effective anthelmintics for con-trolling parasites in sheep may beavailable soon. However, federal ap-proval is involved, and this is time-consuming and expensive. Before anynewly publicized anthelmintic can belicensed for general use by veterinar-ians or livestock producers it must passa rigid test to prove it does not causedamage to humans. These tests are themanufacturers' responsibility.

Once a material has been approved,investigations concerning its use andmode of action may be continued. Anexample of this is the work that hasbeen done with phenothiazine. In 1947several papers were published on thevalue of using this drug in salt. Thesepapers indicated that this form of con-tinuous administration would kill larvalnematodes hatching from eggs in thefeces. In 1951 and 1952 studies werepublished on the mode of action ofphenothiazine in the host and againstthe parasite. These data showed thatsome of the metabolites or byproductsof phenothiazine could be as effectiveas the parent compound. Also, in 1951,information was released indicatingthat finer particles of phenothiazinewere more effective than larger ones,and that divided doses were better thansingle doses, thus initiating the prac-tice of low-level administration. In1953 further papers concerning low-level administration appeared and somepublications indicated that for mosteffective treatment, emphasis should beplaced on pasture rotation and othermanagement factors. Seven years afterthe advocation of phenothiazine saltpreparations and two years after theinitial studies involving low-level ad-ministration, publications appeared onthe development of resistance to phen-

othiazine by certain species of gastro-intestinal nematodes. In 1959 the term"purity" became important and it wasshown that 10-micron particle sizepurified phenothiazine was just as ef-fective in removing parasites as non-purified material having a smaller par-ticle size. Most recently, in 1961, a re-port was published that indicated "syn-ergized" phenothiazine was also meri-torious in its anthelmintic accomplish-ments.

Likewise, other variations involvingphenothiazine have been encounteredwhile making this review. These in-clude mixing phenothiazine with vari-ous materials to make it more palatableor mixing it with other types of an-thelmintics to "promote" a wider rangeof effectiveness for different species ofparasites.

Another compound that has receivedmuch attention for many years is car-bon tetrachloride. This chemical, com-monly used for control of liver flukesin sheep, is sporadically more toxic tothe host than to the parasite. At least28 reports have been published duringthe past 16 years concerning the use ofcarbon tetrachloride. It is notable thatthe majority of these have discussedeither the toxicity of this compound ormethods of administering it so thetoxic effect could be reduced.

New compounds, more effective thanthose already available, ultimately willbe approved for general use by theFood and Drug Administration. Whenthis happens, we may be assured thatsuch compounds have been subjectedto suitable methods of evaluation toinsure the safety and health of animalsbeing treated, individuals administer-ing the drugs, and consumers of lambor mutton.

News releases on newly developedanthelmintics should be considered

carefully to determine whether theyare expressions of things to come orthings available. The use of any unfa-miliar anthelmintic should be used withthe advice of your veterinarian and/oryour county agent.

Finally, livestock producers and allother individuals associated with the

application of anthelmintics to live-stock should recognize that no anthel-mintic ever will be any better than themethod by which it is administered.This means that anthelmintic therapymust be considered as part of and notas the whole management program forparasite control.

Effects of Inbreeding on Performance Traits in Suffolks

RALPH BOGARTDepartment of Dairy and Animal Husbandry

Oregon State University

Four lines of purebred Suffolksheep have been developed from thesame foundation material. Each ofthree of the lines consists of 15 breed-ing ewes and 1 ram while the otherline consists of 45 breeding ewes and3 rams. All replacements were selectedfrom the young stock produced withinthe line. Weight and score of the lambat weaning and fertility of its damprovided the basis for selection. Thelines have been closed since 1954.Lambs produced have varied in levelof inbreeding from 0 to 45%. To givean idea of intensity of inbreeding inrelation to percentage figures presentedhere, a lamb resulting from two gen-erations of full brother x sister coat-ings would be inbred 37.5%.

A thorough study has been madeconcerning the effects of inbreeding ofthe dam and of inbreeding of the lambon birth weight, rate of gain, lambingpercentage, mature size, conformation,and lamb mortality. Inbreeding of thedam or of the lamb had no effect onbirth weight, rate of gain, mature size

(Figure 1), or conformation as indi-cated by score. However, inbreedingdid influence lambing percentage andmortality. The effect of inbreeding wasnot linearly related to these traits.That is, inbreeding above 5% causeda marked decline in twinning and thelevel of 6 to 15% inbreeding was as

Figure 1. Suffolk ewe J 153 produced a lamb in1961 weighing 80 pounds and scoring 86 in con-formation and 85 in condition. This ewe is repre-sentative of the Suffolks used in this research.

10

Table 1. Effect of three levels of inbreeding on mortality, birth type,and birth weight.

% Inbreeding 0-5% 6-15% 15% and over

Total number lambs 104 152 65Number dead 25 34 24Percent mortality 24 22 37Singles 54 108 45Twins 50 44 20Percent twins 48 29 31

detrimental to twinning as higher lev-els of inbreeding (Table 1). It ap-pears that a low level of inbreeding re-duces twinning but higher levels donot prevent ewes from producing sin-gle lambs.

Mortality was not increased by in-breeding until the level of inbreedingbecame relatively high and then in-breeding markedly increased mortality(Table 1). Some of the more highlyinbred lambs, though large at birth,were listless and showed no interest inliving.

It was thought that inbreeding mightresult in some lines showing a markedinferiority while others would performsatisfactorily. Results show that cer-tain traits became lower in certain

lines but that no line showed generalinferiority (Table 2). For example,line 2 was a very rapidly gaining linebut too low in fertility, while line 3was high in fertility but rather high inmortality and low in rate of gain.

It appears that great attention mustbe given to fertility and livability ifclosed-flock breeding is being used toproduce breeding stock that will trans-mit with regularity when used in com-mercial sheep production. The bestcare and management are required toassist in obtaining a good lamb cropand in keeping the lambs alive. Thesetwo traits would also need careful con-sideration in selection of replacementanimals in order to successfully main-tain a closed flock.

Table 2. Performance by lines.

Line Twins MortalityBirth

weight

(pounds)

Rate ofgain'

(pounds) All 35.51 25.86 9.26 0.540 30.79 26.79 9.24 0.531 40.74 25.45 9.09 0.552 28.57 19.05 10.08 0.58

3 50.00 29.00 8.86 0.54

Weaning weight minus birth weight divided by age in days.

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Table 3. Weaning weight and score of lambs in the four lines of Suffolks.

Weaning weight

Conformation

ConditionLine (120 days)

scorer

score2

pounds

1 77 79 802 80 78 783 78 81 790 79 80 81

90 is excellent, 80 is superior, 70 is good.= 90 is prime, 80 is choice, 70 is good.

Inbred sheep will not show as highfertility as outbreds or crossbreds andinbred lambs will be more adverselyaffected by undesirable environmentalconditions. However, inbred stock willtransmit with a greater degree of reg-ularity than outbred stock and will sireoffspring greatly superior to them-selves. Therefore, inbreeding, whenproperly used, is a valuable tool forlivestock improvement.

The performance of the inbred Suf-folks in conformation and condition at

weaning and in growth to weaning issatisfactory as is shown in Table 3.These figures include every lamb thatsurvived to 120 days of age in 1960.

Rams from each of the four lines ofSuffolks have been used on Columbiaand Targhee ewes at the Eastern Ore-gon Branch Station at Union. Thedata on lambs produced by these coat-ings are being analyzed at present. Av-erages indicate that rams from theline having the best gains have siredlambs with the best gains.

Development of a Sheep for Western Oregon

RALPH BOGARTDepartment of Dairy and Animal Husbandry

Oregon State University

Previous studies on the value of va-rious breeds of sheep for fat-lambproduction in western Oregon demon-strated that several breeds possess cer-tain very superior traits but also haveother mediocre traits. Thus, no breedappeared to show superiority in alltraits even though certain breeds weresuperior to others in overall merit. Itseemed desirable to combine the goodtraits of some of the breeds by first

combining breeds and then selectingfor fat-lamb producing ability in theclosed flock that was established fromthe crossbred foundation. The Cheviot,Dorset Horn, and Columbia breedswere combined by crossing Cheviotrams (Figure 1A) with Columbia ewes(Figure 1 B) and Dorset Horn rams(Figure 1C) with Columbia ewes.These crossbred sheep were then com-bined to provide a foundation which

12

Figure 1. (A) Cheviot ram, (B) Columbia ewe, and (C) Dorset ram—typical of those used in producinga foundation for the sheep being developed. (D) Ewe No. I 128 produced one lamb in 1960 weigh-ing 79 pounds at 120 days and scoring 83 in conformation and 81 in condition. In 1961 her Iambweighed 98 pounds and scored 94 in conformation and 94 in condition. This ewe is representative of

the animal being developed in the OSU research program.

has been bred and selected as a closedflock. The Dorset breed was used tobring in high fertility and good milk-ing ability. The Cheviot was used tointroduce open face, good mutton type,and extreme ruggedness. Columbiaswere used because a flock of older,good producing ewes that produced aheavy clip of good quality wool wasavailable.

This combination should make itpossible to develop an open, white-faced sheep that produces large, meaty

lambs carrying sufficient finish to makegood carcasses. Selection is based pri-marily on weight at 120 days of ageand scores for condition and conf or-mation.

Considerable variation exists in theflock under development. This varia-tion is both expected and desirablefrom a genetic standpoint. It is desir-able because variability is necessaryfor effective selection. In developmentof a breed, variation is necessary togive the kind of combinations required.

13

Undesirable combinations also willoccur but this is of little consequencebecause they can be culled. The desir-able combinations are essential forbuilding the kind of flock required. Itis the policy to use several rams (6 to8 each year) in the development ofthis sheep so that fixing of traitsquickly will not result. When traits be-come fixed selection becomes ineffec-tive. Also, several rams of the Cheviotand Dorset breeds were used in the

original matings to give a wide geneticbase.

Production in this sheep is good(Figure 1D). The 112 lambs producedin 1961 averaged 82 pounds at 120 daysof age and scored 88 in conformation)and 88 in condition 2 . No creep feedingwas practiced. The ewes were fed hayand some grain during the lambingseason.

90—excellent ,80—superior, 70—good.90—prime, 80—choice, 70—good.

Responses Obtained from Selecting forTraits of Economic Importance

C. W. Fox, J. A. B. MCARTHUR, RALPH BOGART

Department of Dairy and Animal HusbandryOregon State University

Results reported here are from onlyone of several sheep breeding researchprojects in progress at Oregon StateUniversity and its branch experimentstations.

Performance tests

Each year approximately 50% ofthe Hampshire lambs weaned at theCentral Station are utilized in per-formance testing. Also, Columbia andTarghee ram lambs are performancetested at the Eastern Oregon BranchExperiment Station at Union. Immedi-ately after weaning, the Hampshirelambs are placed on full feed for peri-ods of 55 and 34 days for rams andewes, respectively. Daily gain and feedefficiency records are obtained duringthis performance period. These rec-ords are utilized in an index for se-lecting four ram lambs to be progenytested with Columbia and Targheeewes at the Eastern Oregon Station.

For the past two years the most effi-cient gaining Hampshire ram lamb alsohas sired crossbred offspring whichwere more efficient when placed onperformance test. In 1959-60 the topram lamb was 7% more efficient thanthe other three selected rams and hisrespective offspring were 5% moreefficient than offspring from the otherthree selected rams. In 1960-61 similarresults were obtained and are reportedin Table 1.

Results in Table 1 illustrate thatram C-61 was 6% more efficient infeed utilization than the other threerams, and his selected crossbred ewelambs were 5% more efficient. Al-though these differences are not high,it should be pointed out that the fourram lambs progeny tested were firstselected on the basis of high perform-ance, and little variation existed amongthem for this trait. The conformationand size of the four ram lambs can be

14

Figure 1. Conformation and size of four ram lambs can be noted above. Top photos: C-13 (left),C-15; bottom photos: C-17 (left), C-61.

seen from their pictures taken the daythey came off the performance testJuly 21, 1960 (Figure 1).

This year, among four sire groups,differences in feed efficiency of 36 and20% were obtained for purebredHampshire ewe and ram lambs re-spectively.

Reproductive performance of cross-bred and purebred ewe lambs

Four crossbred offspring (Hamp-shire x Columbia) were selected fromeach progeny tested ram lamb and bredas lambs to further determine their

performance. It is possible to comparetheir performance with that made bypurebred Hampshire ewe lambs. Theincrease in reproductive efficiency ofthe crossbred dam over the purebreddarn is shown in Table 2.

Results from this first year of breed-ing ewe lambs clearly indicate the su-periority of the crossbred dams overthe purebred dams in all traits of eco-nomic importance. This significant in-crease in production can be illustratedfurther by assuming the number ofewe lambs as 100 and determining theeconomic return from both groups.

15

Table 1. Performance record of selected ram lambs and their respectivecrossbred offspring.

Ram number

C-13 C-15 C-17 C-61

Ram lambs (1960)Gain on performance test (lbs.') 62 62 66 65Feed efficiency (lbs. 2 ) 6.16 6.16 5.93 5.70

Four crossbred ewe lambs from each ram (1961)Gain on performance test (lbs. 3 ) 25.3 23.0 25.5 25.0Feed efficiency (lbs.4 ) 7.12 7.00 7.11 6.71

'55-day period immediately after weaning.2 Pounds of feed consumed to produce one pound of gain.'Mean of 4 lambs, 34-day period immediately after weaning.• Mean of 4 lambs.

Table 2. Average value of performance traits from purebred and cross-bred ewe lambs.'

Purebred CrossbredAdvantage of

Crossbred

Number 18 16Body weight 8-31-60 (lbs.) 132 130 NoneBody weight 10-21-60 (lbs.) 139 140 NoneAverage lambing date 3-1-61 2-13-61 1 estrus periodEwes lambing' (percent) 50 94 +44Lambing percentage 3 111 153 +42Death loss first 48 hours (percent) 30 17 +13Pounds lamb weaned per ewe4 56 82 26

'Bred as lambs.2 Based on ewes exposed to ram.'Based on ewes lambing.Lamb weight adjusted to 120 days of age.

Assuming lambs are selling at 15 centsper pound the 100 crossbred damswould return approximately $200 morethan a similar number of the purebreddams. It should be pointed out that theresults are only for one year and thatsuch differences may not be experi-enced with all crossbred ewe lambs.These crossbred ewe lambs were all

sired by Hampshire rams that hadbeen selected because of their highindividual performance. Both groupsof ewe lambs were on an excellentplane of nutrition at all times. Theextra care given both groups duringthe pasture period made it possible tosave some lambs that presumablywould have been lost.

16

Carcass traits

Besides increasing efficiency of hisunit the producer is becoming moreaware of marketing a product that willsatisfy the housewife and make her asteady buyer of lamb. Interest amongOregon producers in carcass valuescan be attested by the number of car-cass contests sponsored by our sheep-men in cooperation with their countyextension agents. More basic informa-tion is needed on the inheritance ofcarcass traits, cut-out-values, and con-sumer preferences before it will be

possible to produce the kind of lambthat will be the most acceptable to allconcerned.

During the past four years resultson carcass-cut-out values have beenobtained on weanling and fed lambs.More data have been obtained on wean-ling lambs and the results have beenextremely valuable in obtaining basicinformation for various carcass traits.Besides carcass data from wether off-spring of the four progeny testedHampshire ram lambs, and the Colum-bia and Targhee lambs, three other

Table 3. Average value of carcass traits by breed of ram

Breed of sheep

Ram breed Hampshire Columbia Targhee Southdown North Dorset HornCountryCheviot

Number of rams 4 2 2 1 1 1

Dam breed Columbiaor Targhee

Columbia Targhee Crossbredewe lamb'

Crossbredewe lamb'

Romney

Number ofcarcasses 20 6 6 5 9

Slaughter age(days) 148 157 151 118 118 124

Carcass grade' 3.6 2.7 2.8 4.0 3.4 4.2Carcass length

(cm.) 60.7 63.1 62.9 51.2 55.6 58.2Carcass weight

(lbs.) 43.1 40.4 41.6 29.9 33.1 38.8Trimmed loin

(lbs.) 4.6 4.5 4.5 3.5 4.2 4.4Meat in legs' (lbs.) 10.6 10.2 10.4 7.2 8.4 9.6Meat in legs' (per-

cent) 24.6 25.2 25.0 25.9 24.8 24.7Fat thickness at

11th rib (mm.) 4.4 2.8 4.4 5.0 3.6 4.8Loin-eye area'

(sq. in.) 1.74 1.54 1.53 1.61 1.73 1.70Loin-eye area ad-

justed to 120 daysof age (sq. in.)_. 1.45 1.18 1.21 1.64 1.76 1.62

I Crossbred ewe lambs were Hampshire rams on Columbia ewes.2 Scores from 5 (prime) to 1 (cull).3 Legs were boned out.

Based on carcass weight.Includes only longissimus dorsi muscle at 11th rib.

breeds of rams were included in 1961.The 1961 results from these six breedsare shown in Table 3.

Results in Table 3 are not compara-ble between breeds because data havenot been adjusted for known environ-mental effects. Hampshire, Columbia,and Targhee lambs were raised at theEastern Oregon station, and the otherthree groups were raised at the Cen-tral Station. At a comparable age theSouthdown sired lambs possessed ahigher carcass grade, thicker fat cover-ing, and slightly smaller loin-eyearea than did those from the NorthCountry Cheviot. As expected, theSouthdown-cross carcasses were shorterin length. Although the Southdown-cross lambs had the smallest weight ofboned leg meat they had the highestpercentage of meat when based oncarcass weight. Lambs sired by theNorth Country Cheviot or Southdownram constitute a three-breed cross andthese lambs had the largest adjustedloin-eye area.

Several trends have been consistentover the past four years. PurebredTarghee lambs have averaged higherin carcass grade and greater in thick-ness of fat at the 11th rib, and gener-ally have had a smaller loin-eye areathan purebred Columbia lambs raisedunder a similar environment. Cross-bred lambs from Hampshire sires havescored higher in carcass grade and car-cass conformation, have been shorterin carcass length, and have had a largerloin eye than purebred Columbia orTarghee lambs. Adjusting the loin-eyearea to 120 days of age, the differencebetween lambs from Hampshire, Co-lumbia, and Targhee sires is even moreapparent. There was a 25% differencebetween the average size of the loineye from lambs of the four Hampshirerams. This certainly indicates that

sufficient variation exists in this traitthat it could be improved by a selec-tion program. Heavier lambs at 120days of age probably will have a largerloin eye.

Various phenotypic correlations havebeen calculated for live animal andcarcass measurements. However, onlya few will be listed. Loin-eye area hasa correlation coefficient of .14, .23, and.34 with conformation score of thelamb, thickness of fat at 11th rib, andUSDA carcass grade, respectively. Thecorrelation was .94 between width ofcarcass hind legs and boned-out meatin legs. Some of these values are highenough that they may be of importancein selecting a lamb with more leanmeat.

Taste panel scores

It is important to know whether ornot eating qualities are significantlyinfluenced by sire or breed of lamb.The 1961 results on 64 roasts from 15sires indicated no significant differencefor any of the eating quality scores.Organoleptic tests were conducted on a7-rib roast and only the longissimusdorsi muscle was used for tasting.Over the past four years similar re-sults have indicated no significant dif-ferences for these taste panel scores.This seems to indicate that for wean-ling lambs of these ages the longissi-mus dorsi muscle is uniformally juicy,tender, and lacking in any strongaroma or flavor. If roasts from thelegs were used for taste scoring theresults could be different because ofthe exercise that leg muscles receive.Results in Table 4 were obtained froma trained taste panel committee of sixpeople. For aroma and flavor of leanand fat a low score is more desirablethan a high score. A high value is moredesirable for the other four scores.

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Table 4. Average value of organoleptic scores by breed of ram.'

Breed of sheep

Ram breed Hampshire Columbia Targhee Southdown North Dorset HornCountryCheviot

Number of rams 4 2 2 1 1 1

Dam breed Columbiaor Targhee

Columbia Targhee Crossbredewe lamb

Crossbredewe lamb

Romney

Number ofcarcasses 20 6 6 5 9 6

Aroma 4.63 4.49 4.52 5.0 4.7 4.9

Texture 4.97 4.46 4.62 5.3 5.0 4.9

Flavor lean 4.54 4.41 3.99 4.5 4.7 4.6

Flavor fat 4.42 4.55 4.66 4.6 4.8 4.6

Juiciness 4.89 4.56 4.61 5.0 4.8 4.8

Tenderness 5.25 4.89 5.21 5.4 5.3 5.2

Overall score 5.05 4.63 4.27 5.3 4.9 4.9

A scale of 1 - 7 is used for scoring.

Although the difference was not sig-nificant, the younger lambs from theSouthdown sire were finer in texture,more juicy, more tender, and weremore desirable overall than any lambsof the other breeds.

Crossbreeding research for 1961-62

Continued research is planned ondifferences in reproduction efficiency

and lamb production between crossbredand purebred ewe lambs and crossbredyearling ewes. This year Columbia andTarghee ewe lambs were included inthis research at the Eastern Oregonand Central stations. Research willcontinue on carcass evaluation andtaste panel scores for various pure-breds, two-breed, and three-breedcrosses.

19

Problems Encountered in Lamb Slaughter

NATE HURT

Regional Lamb Division ManagerArmour and Company

Portland, Oregon

The sheep industry in the Willam-ette Valley has come a long way in thepast 15 years. Lambs now being pro-duced are much better than when Ifirst came to Portland 16 years ago.At that time most of the lambs were abyproduct of the farmers here in theValley. Conformation was poor andnot too much importance was placedon finish or quality. In our opinion,tremendous strides have been made bypeople in producing a better kind oflamb.

Percentage of yield in the carcass isof great importance to the packer.From a yield standpoint, a lamb thatis properly finished, with good con-formation, and with a pelt or skin thatis not too thick or heavy, is the mostdesirable. Dressed carcass weight de-sired by most of his customers rangesbetween 40 and 55 pounds, with aslightly better demand for the 45 to 53pound carcass.

A moderately fat lamb, without toolarge a kidney and not a heavy, "barky"type, is most desirable. This is notmuch of a problem during the monthswhen genuine spring lambs are com-ing to market, but becomes so as weget into the feedlot season of Decem-ber, January, and February. This iswhen we encounter heavy, overfatlambs. It is unfortunate that theselambs cannot be marketed when theyreach a weight of approximately 100pounds and before they become over-

fat. I believe they would bring a betternet realization to the grower or feederthan if held until they weigh 110 to130 pounds, and are too fat and unde-sirable to the retail dealer and his cus-tomers.

As a general rule, heavy, overfatlambs have to be sufficiently discountedto the retailer (enough for him to cre-ate an outlet at a price desirable enoughfor the retail trade) so his customerswill buy cuts from this type animal.The discounted price is reflected inthe price growers and feeders get fortheir lambs.

A lamb that will yield 45% is notworth as much money as one that willyield 50%. Therefore, "filling" by thegrower or feeder is not recommendedbecause a high dressing percentage isdesirable. It might be worthwhile forthe packer to pay a cent or two perpound more to some growers than toothers because of the difference in theyields of their lambs.

Byproducts play a very importantpart in lamb prices. If the packer canget a good price for the pelt, from the"fancy" meats (such as liver, heart,and tongue), and from the green cas-ing, he can pay a higher price to thegrower or feeder.

You are well aware of the presentprice of wool compared to past prices.I remember one time we were getting$14 for a wool pelt. At that time wewere paying 27 to 28 cents a pound

live for lambs and selling the carcassfor 32 cents. But today's price of woolpelts is far, far below this. In fact,some of the pelts (such as a shearedpelt, called a No. 3) are not worth sav-ing. The price for green casings is notgood. Natural sheep casings for sau-sage have been replaced by syntheticcasings ; "fancy" meats (such as lambliver, hearts, and tongue) do not drawa premium price and, at times, aredifficult to dispose of.

Eastern markets have quite a bear-ing on prices in Portland and in thisarea. The only time we can movelambs out of the western area is whena surplus exists that lowers the priceof live lambs to the point where theycan be slaughtered and shipped intoeastern markets. Also, the demand forlamb in eastern markets must bestrong and the price sufficiently highto cover freight costs involved and stillreturn the lower price lambs cost inthe west. If it were not for this east-ern market, we probably would see livelambs priced so cheap during the sur-plus run that no one would want togrow lambs for market.

During the fall months lambs have aNew York warehouse-delivered priceapproximately the same as the Port-land price. Thus it is unprofitable atthis time of the year to ship lambsfrom this area. Not enough demandexists on the west coast to take care ofsupplies.

I have been asked to give my opinionof losses incurred through federal meatinspection. The only losses incurredby federal meat inspection are cer-tainly justified—animals that are dis-eased to a point where they should notbe used for food, and parts of animals(livers, hearts, and tongues) that areinfected with some form of disease orparasite. I am sure you all agree you

would not want to eat any of the meatfrom the kind of animals indicated. Inour opinion, federal meat inspectionshould be mandatory at every slaughter-house and packing house in the UnitedStates.

I would also like to touch briefly onwhat kind of a lamb we will need tomeet customer requirements in the fu-ture—possibly 10 years or so fromnow. This is something about whichwe can only guess but I can tell youwhat I personally think. Future cus-tomer demands will, in all probability,be for a lamb the same weight we arenow producing, with a minimum offat, but young and tender. At the retaillevel this lamb will need to be as bone-less as possible and trimmed so thereis no waste visible to the housewife asshe does her shopping.

I think the packer will have to makea change in the way lambs are dressed.It has been many, many years sincethere has been any change in the waylambs are slaughtered and carcasseshung on the rail for sale. It is possiblethat lambs will be streamlined in carcass form on the kill floor. We havedone some experimenting locally bydressing a lamb on the kill floor in aslightly different way than the generalmethod. We have removed the frontand rear shin bones, removed the tail,taken out the kidney and the skirtmeat, put a galvanized skewer up thespinal column to keep the neck straight.

Our reasoning for this type of dress-ing was : first, the neck curves upwardwhen a lamb is dressed, but by straight-ening it the retailer can get desirable,even, square neck cuts ; then, by re-moving the front and rear shanks,tails, kidneys, and kidney fat, we willbe doing only what the retailer doestoday after the carcass reaches hismarket. Instead of having the retailer

throw waste material in the bone barreland ship it back to the processing plantto be rendered and processed, the

packer keeps it at his plant. This ispossibly a little farfetched, but itsounds reasonable.

Lamb and the Trend Toward Greater Meatiness

ROY A. STEEN

Eugene Packing CompanyEugene, Oregon

ConformationA great deal has been said regarding

lamb, relative to its smooth, blockyconformation. We should discard theword "blocky" and substitute smooth,long-bodied conformation. By smoothwe mean a medium of fat cover, astraight rib carriage (not balloonedout), and a carcass covered with aminimum of fat. By conformation wemean thick muscled, with the minimumof fat covering necessary to createmarbling for tenderness, juiciness, andhigh quality.

Excess fatIn lamb, as in beef, pork, or veal,

you are faced with the problem ofgrowing what the consumer will buy.Also, a product needs to be processedprofitably. You are also faced with theproblem of small volume due to thelack of demand that has been createdby thin-muscled lamb with an excessof fat.

Processing of Iamb

To a processor of lamb, a carcassfrom 50 to 60 pounds is the most de-sirable if it has sufficient fat for mar-bling. The carcass should show a largeloin eye, long rib rack, short loin, thick

meaty shoulder, and a well-muscledleg. All of these indicate desirable con-formation. With a minimum of outsidefat to be removed there will be lesskidney knob fat for the renderingplant. Such a meat type carcass willyield a higher percentage return fromthe more desirable cuts. The breast andflank generally are of no more valuethan are handling costs in wrappingand freezing. Often they are moved ata "dump" price. More emphasis onmuscling of these cuts should be given.Often a well-muscled cut representsthe difference between profit or loss ina processing operation. With more leanmeat in these cuts, the possibility fortheir sale is unlimited. For example :(1) barbecued or charcoal broiled flankand breast would give pork spareribsa run for their money; (2) these cutswhen boned and sold as chopped lambcutlets, without excess fat, can be soldon a par with veal cutlets in self-service counters or on restaurantmenus ; (3) they may be boned andsold as boneless lamb stew.

Potential market

The potential market for processedfrozen lamb cuts seems unlimited.Lamb is tender, tasty meat that freezes

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well. It is a commodity that lends it-self to the processed meat industrywhich emphasizes speed and cost con-trol. It is up to you, the grower, toprovide the main ingredient—qualitycontrol. The time and money involvedin producing and marketing a desirablelamb are considerably less than forbeef. Also a more meaty carcass couldbe sold in volume for use in homefreezers. The cost of a lamb carcasswill fit the family budget of more peo-ple than the extra expense for half ofa beef or pork carcass. More lamb canbe placed on the table with a dollarspent for lamb than can be provided bythis amount in the purchase of pork.

Future trend

The bulk of beef sales in the last 10years has moved toward emphasis on

primal cuts, and this will occur inlamb. Today the super markets arebuying more primal cuts than car-casses. The breakdown into primalcuts of 32 lambs (including utility,good, and choice grades) when com-pared with 22 beef of good and choicegrade yielded 95.8% primal cuts forsix cuts of lamb against 88.04% forprimal cuts of beef. Although not con-clusive, it seems that by producing alonger bodied, meatier lamb, lamb canbe put in a favorable position withbeef and pork from a processingstandpoint.

Yes, the lamb has lost its place onthe American menu because of toosmall a bite of meat in the chop in pro-portion to the fat around it.

It is up to you to produce a meatierlamb.

23

Lamb Carcass Contests

WALTER H. KENNICK

Department of Dairy and Animal HusbandryOregon State University

The primary objective of a carcasscontest is to provide information andeducation to all people interested in themeat industry—producers, packers,marketing agencies, restaurant opera-tors, retailers, educators, and con-sumers.

The ideal carcass contest demon-strates the most desirable carcass foreveryone in the industry, and showsexamples of deviations from the ideal.The contest also should show the rela-tionship of desirable characteristics inthe carcass to those in the live animal.

First of all, the ideal carcass se-lected must be the type in demand bythose selling lamb products to consum-ers. Without further belaboring the"red meat-fat" problem, this carcassmust have a high yield of salable meatof a desirable quality. Studies withpork and beef carcasses, which indi-cate that 70-75% of the variation inyield of salable cuts can be accountedfor by variation in fat content of thecarcass, have shown us the way in se-lecting high yielding lamb cracasses.This same concept has been investi-gated with lamb carcasses and con-firmed by Hoke et al (1). Their inves-tigations pertaining to lamb carcassesof Prime, Choice, and Good grades aresummarized in Tables 1 and 2. Theirdata show that observations most ac-curately measuring waste fat accountfor most of the variation in yield ofretail cuts, while conformation ac-counts for a very small, generally in-significant portion of the variation in

retail cuts. Zinn (2) has confirmedthese results ( % retail fat trim corre-lated with % retail trim cuts gave a co-efficient of r –.78) and has furtherdemonstrated that loin-eye area ac-counts for very little (loin-eye areacorrelated with % retail trim cuts, r =--–.07) of the variation in yieldability.

It must be conceded at this pointthat we currently follow USDA grad-ing in which conformation plays amajor role in final grade, and also thata large loin-eye is a very desirabletrait to consumers—in those retail cutsin which the loin-eye is exposed.

Characteristics indicative of desira-ble quality, to the best of our knowl-edge, are : (youth, as indicated by colorand porosity of the bones, shape of theribs, and color of the lean; marbling,as indicated by fat streaking, feather-ing, and firmness of flank as seen inthe cut carcass ; and texture and firm-ness of the lean meat.

Once criteria for judging have beendetermined, as discussed above, themethod of application must be decidedon. In a carcass contest, one point ofinterest to many segments of the meatindustry is knowledge concerningmethods of selecting desirable carcasses. Therefore, selection should bedone in as expeditious a manner aspossible so that it not only facilitatesthe operation of a large contest butalso is applicable to the commercial se-lection of large quantities of meat.Based on the preceding considerationsand in part following recommendations

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Table 1. Simple correlations within grade-weight groups between yieldof retail trim cuts from the leg, loin, rib, and shoulder and various objec-

tive and subjective carcass measures.

Prime35-45

Prime55-65

Choice35-45

Choice55-65

Good35-45

Good55-65

Conformation .271 .282 .096 .183 .5151 .358Finish grade –.4321 –.7661 –.615 1 –.731 2 –.333 –.8112Fat thicknessover ribeye –.4832 –.853 2 –.785 2 –.6881 –.5742 –.8722

Significan at P< 0.05. 2 Significant at P< 0.01.

Table 2. Simple correlations within grades between various subjectiveand objective measurements and yield of retail trim cuts from the leg,

loin, rib, and shoulder.

Prime Choice Good

Conformation .227 .097 .4301Finish grade –.5811 –.600' –.5321Fat thickness over ribeye –.7741 –.7561 –.7961Total fat trimming –.9211 –.9151 –.8861Carcass weight –.4051 –.4791 –.4481Kidney fat –.7371 –.8481 –.8261

Significant at P< 0.01.

made by J. D. Kemp (3) to the Recip-rocal Meats Conference, the followingprocedures are recommended:

• When possible, all entries should beshown or displayed on foot and in thecarcass as a means of providing educa-tional information.

• Final placing should be based onlyon carcass considerations.

• The local contest committee shouldestablish classes by breed or on an all-breed basis.

• Carcasses should fall within a 40 to60-pound weight range. Where num-

bers warrant, it is advisable to havemore than one weight class with a narrow weight range.

• Judging should be done by a com-mittee of three, preferably one fromindustry, one from the USDA Grad-ing Service, and one from a college oruniversity.

• All carcasses should be code num-bered after slaughter to avoid the possibility of ownership identification bythe judging committee.

• Carcasses should be ribbed perpen-dicular to the long axis of the rib-eye

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muscle so that one rib remains on thehind saddle.

• Loin eyes should be traced andmeasured with a planimeter. Fat thick-ness over the loin-eye should be takenat the center of the long axis of the eye and at each end where the curvestarts. These three measures should beaveraged. An additional fat measuresshould be made 3 inches beyond thelateral edge of the loin-eye muscle.

while fat covering over the rib mustnot exceed the following specifications:

Min. loin-eyearea per 100 lbs. Max. fat

carcass wt. thickness

(square inches) (inches)

Carcassweight

(pounds)40 15 4.50 .3546-50 4.40 .3551-55 4.30 .4056-60 4.20 .40

• Judges should make their decisionsusing their estimate of-

Cutability based on : thickness offat cover ; amount of kidney and pelvicfat ; area of loin eye ; and relative pro-portion of cuts.

Quality based on : marbling; colorof lean and fat ; age as estimated bybone structure and color of lean; andfirmness of lean and fat.

• Carcasses should be grouped intofive categories as follows : 1-al . Highlydesirable carcasses with a uniform butnot excessive fat covering, thicklyfleshed, and possessing excellent qual-ity characteritics. They should be trimand not show excess kidney and pelvicfat and they should possess qualityequal to or exceeding USDA AverageChoice. The loin-eye area per 100pounds carcass weight should meet orexceed the following specifications

2-a. Carcasses with quality equal togroup 1-a but with slightly less thanminimum loin-eye area or slightly morethan maximum fat or both or one withconformation somewhat less desirable.3-a. High quality carcasses that arelacking in muscling and/or excessivelywasty resulting in low cutability.1-b. Carcasses with very desirable conformation and cutability but with qual-ity below the grade Average Choice.2-b. Carcasses lacking in both cutabil-ity and quality.

• Numerical placing of carcassesshould be on an individual basis using1-a carcasses first and then 2-a or 1-band so on through the groups, depend-ing on the degree to which they deviatefrom the most desirable.

1, 2 and 3 refer to cutability ; a and brefer to quality.

REFERENCES

1. Hoke, H. E., C. E. Murphey, W. E. Tyler, J. C. Pierce and M. M. Van Zandt. "FactorsAffecting Yield of Cuts in Lamb Carcasses." Presented at the 14th Reciprocal MeatConference, Knoxville, Tennessee. June 20, 1961.

2. Zinn, D. W., "Cutting Methods as Related to Lamb Carcass Evaluation." Presented atthe 14th Reciprocal Meat Conference. Knoxville, Tennessee. June 20, 1961.

3. Kemp, J. D., "Recommended Procedure for Quality Lamb Contests." Presented at the14th Reciprocal Meat Conference, Knoxville, Tennessee. June 20, 1961.

26

New Methods In Wool Marketing

R. A. WARD

General Manager, Pacific Wool GrowersPortland, Oregon

Core testing

Taking the guess out of wool mar-keting is now a possibility. It onlyremains for wool growers to availthemselves of the services of their ownorganization which is prepared andequipped to perform the various neces-sary technical tests which establish thereal and actual value of wool. Themanufacturer buys grease wool on thebasis of clean content or yield. In buy-ing grease wool in the field, clean con-tent is the controlling factor. Cleancontent means the amount of cleanwool that remains in a pound of greasewool, after the grease, suint, vegetable,and other foreign materials are re-moved.

It has been possible, for severalyears, to ascertain the clean yield orshrinkage of grease wool by core test-ing. Handlers have been using thismethod for some time. Cores aretaken from representative bales orbags, usually one core to the bale orbag. These core samples are then sentto one of the commercial testing com-panies that test wool on a commissionbasis. There the samples are carefullyscoured and the actual yield andshrinkage of the wool is obtained.

If the clean value of 4 blood valleywool is $1 a pound, and the woolshrinks 45%, the grease value natu-rally is 55 cents. In other words, 45pounds of clean wool is recovered from100 pounds of grease wool. If the woolis exceptionally light, for example

41% shrink and 59% yield, the greaseprice would be 59 cents. It is of eco-nomic importance for a grower toknow what his wool yields.

It is well known in the wool tradethat the possibility of profits, and muchof the profit in the wool buying in-dustry in the past has been due to"over-shrinking" of the wool by buy-ers. For example, the buyer estimatesthat the wool will shrink 45%, andadds a safety margin of 1 or 2% toprotect himself. If he buys it on thebasis of 48%, and the wool actuallyyields 55% or has a 45% shrinkage,the wool grower loses 3 cents a pound.In a practical operation of core testingit does not pay to core test small lotsof wool as the cost of coring runsapproximately $25 a sample.

How then can the small wool pro-ducer receive the benefits of coring?This can be accomplished by assem-bling large accumulations of similarwools, grading them, and them com-bining them into sizable lots of similarquality grade and shrinkage. Experi-enced graders and marketers who havehandled these wools for years are ableto estimate shrinkage and yield onmost wools within 1 or 2%. Thesewools are then placed in a lot with thesame shrinkage range and then cored.This gives a small grower the fairestpossible estimate of shrinkage andyield, and the nearest to an actualfigure that he can secure by anymethod.

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Grading by micron

The micron system is used to de-termine the diameter of fibers and thegrade of wool. It is a recent advancein wool marketing. The old method,commonly called the American system,of classifying grades of wool was tocall them fine, half-blood, *th's blood,I blood, low 4 blood, and braid. ThisAmerican system grew up in the earlydays when crossbreeding with Merinosheep resulted in the establishment ofthese grades. In our opinion it is avery imperfect method of gradingwool, and it is seldom used now bymanufacturers and marketing agencies.However, the grade names are stillused, but usually accompanied by thespinning count, which originally wasthe English system. Theoretically thenumerals used to designate gradessignified the spinning capacity of thewool. For example, a fine wool witha spinning count of 70s would spin70 hanks of yarn, weighing approxi-mately a pound. Each hank is 560yards in length. Braid wool with aspinning count of 36s would spin 36hanks of yarn, and so on. This methodis now being further refined by use ofa machine to determine the diame terof the fiber by microns. A micron is1/25,000th of an inch.

The following are the grades of wooland the micron measurements showingthe diameter:

Fine wools 21.4 m icrons 64's for fine

Half blood 25.0 microns 60's for half-blood

kith's blood 28.0 microns 50's for 43 th's blood

./t blood 31.4 microns 50's for blood

Low VI blood 34.0 microns 46's for low IA blood

Common and braid 37.3 microns 40's for braid

We now have facilities available for"microning" wools to determine thegrade. This method is available whendisputes arise as to the actual grade ofthe wool. This custom service is fur-nished, as is the coring method, andfor about the same price. Some millshave even suggested that they wish tobuy not only on the core test, but alsoon the micron test. However, this testhas not come into general use to anyextent.

Practically all mills maintain test-ing laboratories in which they havemachines for measuring the microndiameter of their wools. We use thecommercial testing companies whenwe find it necessary to determine themicron count of a particular lot ofwool.

Proposed micron specificationA specification using micron meas-

urements for grades of grease woolwas prepared by the U. S. Departmentof Agriculture Wool Laboratory, Den-ver, Colorado.

You can see that there are a numberof factors which determine the valueof wool. Making use of these factorsin marketing wool will increase thewool grower's income.

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