The objective of this experiment was to study the feasibility of maintaing ewes in drylot on a limited ration during the postweaning - pre-flushing period. The cost of treatment and resulting ewe performance were used to evaluate the feasibility

Dearborn, D. D.

Minyard, J. A.

Public Research Access Institutional Repository and Information Exchange

South Dakota State UniversityOpen PRAIRIE: Open Public Research Access InstitutionalRepository and Information ExchangeSouth Dakota Sheep Field Day Research Reports,1967 Animal Science Reports1967Influence of Nutrition During the Postweaning-Preflushing Period on Ewe PerformanceJ. A. MinyardSouth Dakota State UniversityD. D. DearbornFollow this and additional works at: http://openprairie.sdstate.edu/sd_sheepday_1967This Report is brought to you for free and open access by the Animal Science Reports at Open PRAIRIE: Open Public Research Access InstitutionalRepository and Information Exchange. It has been accepted for inclusion in South Dakota Sheep Field Day Research Reports, 1967 by an authorizedadministrator of Open PRAIRIE: Open Public Research Access Institutional Repository and Information Exchange. For more information, pleasecontact michael.biondo@sdstate.edu.Recommended CitationMinyard, J. A. and Dearborn, D. D., "Influence of Nutrition During the Postweaning-Preflushing Period on Ewe Performance" (1967).South Dakota Sheep Field Day Research Reports, 1967 . Paper 12.http://openprairie.sdstate.edu/sd_sheepday_1967/12SOUTH DAKOTA STATE UNIVERSITY Brookings , South Dakota Cooperative Extension Servi ce Li vestoclt _Specl.alist� Section . INFLUENCE OF NUTRITION. DURmG THE POSTWE.ANING· -. . PBEFWSHING · · PERIOD ON EWE .PERFORMANCE J. A. M:inyardl and D. D.  Dear"t>orn2 Many sheep producers follow·-the practice of f'lushing--ewes- · prtor-· tct· -and- during breeding se .as on for the purp0s e  of improving reproductive performance .  Many' -exper­imental tri als. designed to evaluate the effectiveness.. of · flushing · have �hown that ewes whi ch are flushed drop a . higher . ,pre · cent lamb crop. However , some tr.ia.J.s·' have shown no beneficial. effect from flushing. One of the explanations .. frequently offered for a lack of· response t o  the tl.ushing treatment . is  that the. ewes -vere·-too .fat pri or to flushing . Many 'festern South Dakota sheep operators who formerly l ambed . late on - the - -re.nge have acquired lambing sheds and are lambing earlier . Since lambs are dropped earlier in the year they are of'tt;n weaned earlier . 'Ibis - sched11Je _alJ.ovs-.-tbe dry ewe , to graze for a longer period during the normal growing_ sea.son . Tb.is -s chedule under favorabl e pasture conditions m� allow the dry ewe to. become· -f'atter than neces sary before flushing and rebreed.ing. Pasture. costs per ewe during the summer are considerably hi gher than those which were common a few years ago . Present monthly pasture charges of $0 . 60 to $1. 00 per ewe are common . The objective of this experiment was to study the feas ibility of maintaining ewes in drylot on a limit ed r ation during the postweaning - pre-flushing period . The cost of treatment and resulting ewe performance were used to evaluate the feasibility. Procedure One hundred twenty-four .ewes of mixed ages and mixed breeding � primarily· Ram- . bouillet , Corriedale and Columbi a., ·were assi gned to thi s trial on August 8 ,  1964 . The ewes averaged · 125 pounds at the time the trial was init iated whi ch was approx­imately r we.�ks �ter their previous lambs were weaned . The ewes were strat ifi ed by age wi �h 7 5  ewes· as�igned to a drylot treatment a.nd the remaining 49 ewes· ·- al­lowed to graze ·fair to, ..good condition pastures at the Newell .station . The ·treatment period was · 54 dey-s in length with the ewes i.n the d?ylot receiving approximately 2 pounds of fair to poor quality prairie hay per head per dey- . It was estimated.. that this dai :ly' allowance of hay would provide approximately two-thirds· of'·· the total diges tible nutri ent requirement re commended by the National. Research. Council. for maintain ing the body weight of a 120 pound dry ewe. At the conclusion of the treat­ment period the two groups of ewes were weighed and re combined to r eceive the same flushing , breedin·g and wint ering treatment . 1 Extens ion Livesto ck Speci ali st 2Present Addres s :  Extension Livestock Spec ialist � University of Nebr aska, Lincoln. 63 - 2 -No supp lements other than minerals were fed to either group of ewes during the t.ri al . A mixture of trace-minerali zed salt and steamed bonemeal was available on a free-choice basis t o  the d.rylot ewes . The pasture ewes had acces s  to trace­mineralized salt . Following the tri al period both groups of ewes grazed the s ame pasture and received 3/4 to 1 pound of rolled barley per head daily as the flushing tr eatment . The flushing period started 19 deys before and extended 3 weeks into a 1 week breeding season . Approximately 1 pound of rolled barley per ewe per dS¥ was pro­vided the last 6 weeks before lambing.  The ewes were shorn approximately 2 weeks before the start of the lambing season . Thi s  s ame procedure was followed in 1965  with 163 ewes ass igned on June 29 , at the time their lambs were weaned .  Seventy-one ewes ,  mreraging 121 pounds , were ass igned to the drylot treatment and 92 ewes , averaging 115 pounds , were trucked to the Antelope Field Station and allowed to graze good condition native range . The 1965 tr!-� period was 94 deys in length. Results Experimental results for 1964 and 1965 are presented in Tab le 1. The Newell Station pastures ( 1964 ) and Antelope native range ( 1965 ) provided nutrients in exces s of that which i s  required for body maintenanc e by 120 pound dry ewes . The pasture ewes a'Veraged · ga.ins· · ·or 14 to 7 pounds during the 1964 and 1965 triaJ. periods respect ively.  In contrast , the drylot ewes whi ch were limited to approximately 2 pounds of fair to poor quality Prairie bay per ewe per day averaged losses of 5 to 8 pounds during the 1964 and 1965 tr ial periods , r espectively . All groups o f  ewes gained in weight during the prebreeding flushing period . '!be ewes which had received the limited ration in the drylot gained much more rapidly during the prebreedin g  flushing period than did the pasture ewes . Ewe death loss during the 1964-6 5 winter was greater for the ewe s which received the limi �ed rati on the previous summer .  Causes for the loss are not apparent and may or m� not be related to treatment . No differences were · noted in the 1965-66 trial. Per cent dry ewes and per cent lamb crop born was es sent ially the same for each group of ewes the first year . An exceptionally high ;, :::; 1� ce..::.ta.ge of dry ewes was noted the s econd year , the result apparently of an infertile ram . However 9  s ince the ewes were stratified by summer treatment group and as si gned t o  single­s ire breeding pasture s , comparis on of the treatment groups seems valid. More dry ewes were noted in the group mai ntained on a limited ration in the dry lot . Per cent lamb crop born was s imilar for the two groups of ewes during the second tr ial. Average lsmbing date was 4 d� earlier for the pasture ewes the first year and l dey earlier the sec ond. Grease fleece wei ght was approximately 3/ 4 to 1 pound per head greater for the pasture ewes when compared with the dry lot ewes which had received the iimi ted r ation . 64 - 3 -Discussion Tht body weight changes due to the treatments evaluated in this experiment did not -Jfect reproductive performance serious ly .  However , a larger per cent o f  dry ewes w�re noted in the:. drylot lim ted fed group the second year . The pasture ewes were in good condition at the end of the postweaning - prebreeding period but s till responded to  the flushing treatment with an additione.l. gain in body weight . The larger flushing gain by the drylot ewes did .not appear to offer any a�ditional benefits in per cent lamb crop.  Therefore , if condition limits  the effectivene ss ot flushing , it would appear to be at a. higher degree of condition than was en­countered in the pasture ewes of this experiment . Two pounds of poor to fair quality prairie hay did not meet the maintenance requirements of the ewes.  However ,. this only affected reproduction slightly. The limited ration did not provide sufficient nutrients for optimum wool produc­tion . Protein supplementation with the li.l!lited hay ration may correct this de­ficiency. '!he cost of providing e l imi ted ration of hay may be less than the cost of pasture. Assuming a $15 .  00/ton value for the hay , the ccst of providing ewes 2 pounds per hay per day would be appr oximately $0 . 45 per ewe per month. This doe s not include the cost of labor and equipment required for feedin�. Therefore � the feasibility of the drylot limit ed ration is dependent upon the co st and availabili­ty of the pasture . If the range is limited or if rental rates a.re $1. 00 or more per head per month the dryl.ot proc edure deserves consideration . It may be used some years to prevent over use of the available range . However , if pasture is available at reas cnable rates these data would indicate no advantage for caifin­ing ewes to a drylot on e l imited ration . Summary More than 100 grade western ewes were utili zed each year in a. 2-year study to evaluate the influence of nutr i tion during the pos twean in g  - prebreeding period on ewe performance . Each year one group of ewes was retained in dry lot and limited to approximately 2 pounds of prair ie bay per ewe daily . The remaining group was a.llowed to graze Newell Station pastures or native range . The drylot ewes lost wei ght during the trial period while the pasture ewes gained weight . Both groups of ewes gained weight during the prebreeding flushing period . No differences in reproductive performance were noted between treatments the first year however , there were mare dry ewes in the drylot group during the second trial . Wool pro­duction was greater for the pasture ewe s .  Feed costs  may be less for the drylot ewes on the r estricted ration . However , the additional labor required for feeding and less income fran wool indicate no economic advantage with conditions that were associated wi th thi s experi�nt . 65 � Table 1. Influences of Nutrition During the Postweaning - preflushing Per iod on Ewe Performance length of Postweaning - Prebreeding Period Period Covered Preceeding Lambs Weaned Initial Weight , tb .  Final Weight , Lb. Weight Changes , Lb . Weight at �tart of Breeding Season Weight Gain During Prebreeding, Flushing Period Death Loss During Winter , No . Per Cent Dry Ewes Per Cent Lamb Crop Born ( c f Ewes Lambing) Average Leatbing Date Average Grease Fleece Wei ght , LQ . j ( ) Indicates Number of Head " \ \ Newell Fi eld Station 1264 Dry Lot Pasture Dry Lot 54 days 8-8 to 10-1 6-22 126 ( 75 )  12 3  ( 49 ) 121 ( 71 )  1 21 {75 ) 137 ( 49 )  11 3 ( 71 )  _ c;  +14 -8 132 ( 75 )  141 ( 49 )  122 ( 7 1 )  11 4 9 3 0 3 5 4 23* 163 165 133 March 30 March 26 Apr il 7 8 . 98 9. 75  8 . 33 *All Ewes assigned to 1 breeding_ �asture were open , apparently the ram was infertile . \' \ . 1962 9 4  days 6-29 to 10-1 6-29 Pasture ll 5  ( 92 )  122 (92 ) +7 '° '° 125 ( 92 )  3 3 16* 131 April 6 9. 43 

Influence of Nutrition During the Postweaning-Preflushing Period on Ewe Performance

https://openprairie.sdstate.edu/cgi/viewcontent.cgi?article=1011&amp;context=sd_sheepday_1967

Influence of Nutrition During the Postweaning-Preflushing Period on Ewe Performance

Abstract

Similar works

Full text

Available Versions

Public Research Access Institutional Repository and Information Exchange