Using Proven Genetics in an AI Program*

Transcription

1 Using Proven Genetics in n AI Progrm* D.J. Schfer 1, J.K. Hden 1, S.R. Brtholomew 1, M.T. Griffin 1, M.E. John 1, J.L. Prcell 2, nd D.J. Ptterson 3 1 MFA Incorported, Columbi, MO; 2 Division of Agriculture Economics, University of Missouri, Columbi; 3 Division of Animl Sciences, University of Missouri, Columbi *Reserch supported by the Vlue Added Producer Grnts progrm from USDA Rurl Development nd Coopertive Progrms, Wshington, DC. Introduction The development of methods to synchronize estrus in beef cttle hs been refined to point tht is fesible s well s resonble to obtin pregnncy rtes in mixed popultions of cycling nd nestrous cows tht exceed 50% to single fixed-time rtificil insemintion, provided progestin bsed estrus synchroniztion protocol is used (Lmb et l., 2001; Kojim et l., 2002; Perry et l., 2002; Kojim et l., 2003, 2003b; Bremer et l., 2004; Stegner et l., 2004; Bder et l., 2005; Schfer et l., 2005; nd Lrson et l., 2006). However, despite this level of success, recent surveys indicte tht fewer thn 10% of beef cows in the U.S. re bred rtificilly. Perhps prt of the reson for the low doption rte of these technologies is due to the fct tht there is little if ny documented evidence of the economic vlue tht is dded s result of this chnge in breeding mngement. Furthermore, to the knowledge of the uthors there hs been no published dt regrding the differences in vlue tht my be ttined over time from both terminl groups of nimls nd replcement femles, sired by bulls: 1) in nturl service setting; 2) the result of AI to older sires with predictble expected progeny differences; or 3) younger AI sires with limited dt vilble to support their expected progeny differences. Therefore, the objective of this experiment ws to determine the economic impct of using proven genetics in n AI progrm. Terminology & Abbrevitions AI Artificil Insemintion EPD Expected Progeny Difference High Accurcy Sires (HAS) AI Sires with ccurcies 0.85 for BW, WW, nd YW EPDs t the time of synchroniztion nd AI Low Accurcy Sires (LAS) AI Sires with ccurcies < 0.85 for BW, WW, nd YW EPDs t the time of synchroniztion nd AI Clving Ese Sires (CES) AI Sires with high ccurcies tht were bred exclusively to virgin heifers NS Nturl Service used fter one round of fixed-time AI Experimentl Design The clves used in this project were the result of mtings from tril compring pregnncy rtes resulting from fixed-time AI to one of two estrus synchroniztion protocols t four loctions. A profile of the sires represented in this tril is summrized in Tble 1. A common, high-ccurcy AI sire ws used t Loctions 1, 2, nd 4. Clves t ll loctions were wened ccording to MFA Helth Trck requirements ( with the first round of vccintions given prior to wening. Clves were wened on the sme dy within ech loction, ll loctions wened within two week period, nd ll clves were shipped to the sme 181

2 feedlot on the sme dy. Clves from the 4 loctions were commingled nd ssigned to pens within breed type, by sire group (HAS, n = 96; LAS, n = 101; CES, n = 38, nd NS, n = 93), nd weight, nd fed common rtion throughout the durtion of the tril. The cttle were hrvested over 63 dy period nd determined to be finished ccording to ultrsound mesurement of bck ft thickness between the 12 th nd 13 th rib, live weight, nd visul observtion of ft deposition ptterns. All nimls included in the nlysis were hrvested t the sme commercil processing fcility nd individul crcss mesurements were collected. To eliminte mrket vrition tht my hve existed the yer during which the tril took plce, feeder clf vlue ws determined using the Knss Stte University price slide eqution (Dhuyvetter et l., 2001) bsed on the three-yer verge of fed cttle nd corn futures. Crcss vlue ws determined using dressed weight vlue bse of $137.32/cwt bsed on 50% of the gross hot crcss weight for pen of cttle grding Choice or better, with premiums nd discounts dded to the bse price for ctul performnce of cttle in their respective sire groups. The vlue of premiums nd discounts ws bsed on three-yer verge historicl USDA Agriculture Mrketing Service reported vlues (Tble 2; USDA, 2006) nd did not fluctute bsed on mrket sesonlity. Tble 1. Profile of breed mkeup nd number of sires used t ech loction. Loction Cow Breed Breed of Sires HAS LAS b CES c NS Sires d 1 Angus Angus 1 e Red Angus / Gelbvieh Red Angus Angus Angus 1 e Angus Angus 1 e Number of different high ccurcy (HAS) AI sires, which hd BW, WW, nd YW EPD ccurcies 0.85 t the time of breeding t ech loction. b Number of different low ccurcy (LAS) AI sires, which hd BW, WW, nd YW EPD ccurcies < 0.85 t the time of breeding t ech loction. c Number of different clving ese (CES) AI sires with high ccurcies but bred exclusively to virgin heifers t ech loction. d Number of different nturl service (NS) sires used t ech loction. e The sme high ccurcy AI sire ws used t Loction 1, 2, nd 4. Results Economic Vlue. The most importnt fctor contributing to the sustinbility of production griculture is the net economic return creted nd cptured by implementtion of production prctices bsed on decisions nd gols estblished by the mnger(s). Due to Tble 2. Historicl vlue of premiums nd discounts ($/cwt) reported by the USDA Agriculturl Mrketing Service for 50% Choice/50% Select pen of cttle. YG/QG Prime Certified Choice Select Stndrd 1 $25.91 $19.69 $9.84 ($3.88) ($16.39) 2 $24.42 $18.20 $8.35 ($5.37) ($17.88) 3 $22.93 $16.71 $6.86 ($6.86) ($19.37) 4 $14.63 $8.49 ($1.44) ($15.16) ($27.67) vrible mngement prctices on ech frm prior to wening tht cn not be ccounted for in the model, nd which my ffect production levels nd vlue of clves t wening, differences in vlue of clves t wening mong the different sire groups ws not nlyzed. Tble 3 illustrtes 182

3 for ech sire group the verge weight, clf vlue ($/hd) t the strt of the tril (entry into the feedlot), feedlot expenses, revenue, net return, nd the difference in net return reltive to the HAS group fter conclusion of the tril. Although the clves in the HAS group entered the feedlot t sttisticlly the sme vlue s the clves in the LAS nd CES groups, following the conclusion of the tril, the HAS clves hd n verge net return of $50.69 nd $53.83 greter thn the LAS nd CES clves respectively. Additionlly the HAS group hd $41.76 greter initil vlue thn clves in the NS group, subsequently the HAS clves finished with $89.66 more in net return which corresponds to $47.90 increse in vlue dded during the tril. Ech loction involved in the study mde pedigree records vilble on the cows in their respective herds, mking it possible to nlyze the differences in vlue tht existed between clves from the vrious sire groups tht were out of n AI sired or nturl service sired dm to estimte the lifetime vlue difference tht exists between different groups of replcement heifers. Tble 4 shows the expected differences in lifetime vlue tht exist between heifers from the HAS group compred to heifers from the NS group ssuming: 1) one round of rtificil insemintion to high ccurcy sire ws performed on the HAS sired dughters ech subsequent breeding seson; 2) rtificil insemintion ws not performed on NS sired dughters (trditionl mngement in most opertions); nd 3) the sme qulity of high ccurcy nd nturl service sires represented in these dt were mted to those femles over their productive lifetime. Tble 3. Averge pre-conditioned clf weight, vlue, totl fed cttle revenue, totl feedlot costs, nd net return for clves in the high ccurcy (HAS), low ccurcy (LAS), clving ese (CES), nd nturl service (NS) sire groups nd net return dvntge of the HAS group reltive to the other groups. HAS LAS CES NS Ave pre-conditioned clf weight 668 w 685 x 646 y 597 z Ave pre-conditioned clf vlue ($/hd) $ wx $ w $ x $ y Totl fed cttle revenue ($/hd) b $ w $ x $ x $ y Totl feedlot costs ($/hd) c $ w $ x $ x $ y Net return $70.50 x $19.81 y $16.66 yz ($19.17) z Net return reltive to HAS $50.69 $53.83 $89.66 Averge feeder clf vlue ($/hd) bsed on Knss Stte University price slide eqution using the threeyer verge of fed cttle nd corn futures. b Determined using dressed weight vlue bse of $137.32/cwt bsed on 50% Choice/50% Select pen of cttle, with historicl vlues for premiums nd discounts s reported by USDA Agriculturl Mrketing Service dded to the bse price for ctul performnce of cttle in their respective sire groups. c Includes yrdge, feed costs, ntibiotic costs, interest on the feeder clf vlue, nd interest on hlf of ll other costs. w,x,y,z Vlues with row contining common superscript re not different (P > 0.05). Tble 4. Estimted lifetime vlue dvntge of high ccurcy (HAS) sired replcement femles compred to nturl service (NS) sired replcement femles. Expected verge lifespn (yr) Lifetime vlue difference ($/replcement femle) 4 $ $ $ $ Net present vlue computed ssuming 3% discount rte. 183

4 Morbidity. Approximtely 60 to 70 dys into the strt of the tril there ws respirtory outbrek, which ws dignosed by veterinrins to be Bovine Respirtory Syncytil Virus (BRSV). Since there were no NS sired cttle from Loction 4 they were excluded from the nlysis of morbidity rte. A significntly lrger percentge of NS sired clves were treted for respirtory problems thn HAS clves, LAS clves, nd CES clves, but tretment rtes mong different AI sire groups were similr (Tble 5). Furthermore, clves from the sme sire group but originting from different loctions, hd similr tretment rtes, which suggests tht genetics my ply greter role in disese resistnce thn wht hs been previously reported (prewening, h 2 = 0.10; post-wening, h 2 = 0.06; Muggli-Cockett et l., 1992). Tble 5. Number of clves nd comprison of respirtory tretment rte mong high ccurcy clves (HAS), low ccurcy clves (LAS), clving ese clves (CES), nd nturl service clves (NS) from loctions 1, 2, nd 3. HAS LAS CES NS n Treted 6.3% 11.9% 16.0% 39.8% b,b Columns contining common superscript re not different (P > 0.05). Crcss Chrcteristics. Despite the fct ech sire group were hrvested t the sme verge yield grde (Tble 6), which suggests tht ll cttle were hrvested t the sme point reltive to being finished, there were significnt differences mong sire groups for verge qulity grde (Tble 6, Figure 1), ribeye re (REA) determined by instrumentl mesurement, hot crcss weight (HCW), nd ge t the time of hrvest (Tble 6). Tble 6. Number of cttle, percentge grding Prime, Certified Angus Beef (CAB) or better, nd Choice or better, men qulity grde (QG), yield grde (YG), ribeye re (REA), hot crcss weight (HCW), nd ge t hrvest for clves in the high ccurcy (HAS), low ccurcy (LAS), clving ese (CES), nd nturl service (NS) sire groups. Sire Group n Prime (%) CAB or better (%) Choice or better (%) QG YG REA HCW Age (d) HAS Choice LAS bc 18.8 b 76.2 bc Choice b b 690 b 430 b CES b b Choice c b 660 c 443 c NS 93 0 c 14.0 b 67.7 c Choice - b b 646 c 416 d Totl Choice ,b,c Vlues within column contining common superscript re not different (P > 0.05). 184

5 100 Percentge (%) b,c b c 20 0 b b b,c,b c Prime CAB or better Choice or better HAS LAS CES NS Figure 1. Distribution of qulity grdes by high ccurcy (HAS), low ccurcy (LAS), clving ese (CES), nd nturl service (NS) sire groups.,b,c Brs within set contining common superscript re not different (P > 0.05). Discussion The difference in net vlue between clves from the HAS group when compred to the other groups, illustrtes tht the current mrketing strtegies tht exist in the mrket plce tody for wened or preconditioned clves do not ccount for or py cow/clf producers for the true differences in economic vlue due to the genetic merit of their clf crop. If it is priority for producer to cpture the full vlue tht is creted from improved genetics through the use of rtificil insemintion one must first know the vlue of the genetic bse tht exists in his or her cow herd from which the AI sired clves were produced. To determine tht vlue nd position one s self to negotite fir feeder clf vlue for future clf crops, individul crcss dt must be cptured on subset of progeny. This mens in the beef production setting tht exists tody, producer must either retin full or prtil ownership of the clves or mke shring of production nd crcss dt contrctul term of sle. The economic nlysis of this tril ws designed so the bse price nd grid premiums/discounts were constnt, thus eliminting the potentil effect mrket sesonlity could ply on ny prticulr sire group reltive to when the respective cttle in group were hrvested. Historicl dt of qulity grde premiums illustrtes tht in spring mrkets for fed cttle there is stedy increse in qulity grde premiums reching pek sometime between mid-april nd mid-my before shrply decresing. Considertion of tht fct illustrtes to optimize net return 185

6 on spring born clves, with genetics cpble of chieving high percentge choice, nd which will be hrvested between 13 nd 18 months of ge, it is impertive for those clves to be finished nd redy to be mrketed t s young of n ge s possible. Clves in the HAS group when compred to ll other groups were hrvested t the sme yield grde with higher verge qulity grde t younger ge, which corresponds to the time of yer when trditionlly the choice/select spred would be t its highest point. Therefore, the differences in vlue tht existed mong sire groups my hve been mplified if the nlysis were to include the historicl sesonlity of fed cttle mrkets. The difference in expected lifetime vlue of heifers from the HAS group over heifers from the NS group further illustrtes the vlue tht is creted from reproductive mngement prctices, however, creting dded vlue is worth nothing, unless steps re tken to cpture prt of the dded vlue. The vlue differences shown between the two groups of heifers re bsed off of the vlue tht hd been dded in those herds through previous use of AI to sires with potentilly but not necessrily similr EPD ccurcies nd/or genetic merit in reltion to the high ccurcy sire used in this tril. Wht is unknown t this time is the potentil vlue tht cn be creted by dhering to strict mngement system tht includes AI only to sires with high ccurcies nd genetic merit similr to tht of the high ccurcy sire used in this tril, nd the extent to which tht vlue could be mgnified. While the intention of this tril ws not to determine the effect of different sires on the helth of cttle of different genetic bckgrounds, the differences in tretment rte tht existed mong the different sire groups is noteworthy point. The differences tht existed in this tril rise questions for future reserch to determine whether the heritbility of disese resistnce is higher thn the vlues reported by Muggli-Cockett et l., 1992, or if through the use of high ccurcy AI sires there cn be indirect selection pressure pplied to their progeny for disese resistnce. Conclusions nd Implictions Estrus synchroniztion nd rtificil insemintion to sires with high ccurcy re both reproductive mngement tools tht provide the opportunity to increse the profitbility nd mrketbility of terminl clf crops in ddition to incresing the vlue of cow herds. Furthermore, while rtificil insemintion to sires with high ccurcy my not lwys result it optimized performnce for every trit, it offers the gretest probbility of mking improvements in the trits to which selection pressure is pplied. 186

7 Literture Cited Bder, J.F., F.N. Kojim, D.J. Schfer, J.E. Stegner, M.R. Ellersieck, M.F. Smith, nd D.J. Ptterson A comprison of progestin-bsed protocols to synchronize ovultion nd fcilitte fixed-time rtificil insemintion in postprtum beef cows. J. Anim. Sci. 83: Bremer, V.R., S.M. Dmin, F.A. Irelnd, D.B. Fulkner, nd D.J. Kesler Optimizing the intervl from PGF to timed AI in the CoSynch+CIDR nd 7-11 Synch estrus synchroniztion protocols for postprtum beef cows. J. Anim. Sci. 82(Suppl. 2):106. Dhuyvetter, K.C., T. Schroeder, nd W. Prevtt Impct of corn nd fed cttle prices on feeder clf price slides. KSU Reserch nd Extension Guide MF Knss Stte University, Mnhttn, KS. Kojim, F.N., J.E. Stegner, B.E. Slfen, R.L. Ekins, M.F. Smith, nd D.J. Ptterson A fixed-time AI progrm for beef cows with 7-11 Synch. Proc. West. Sec. Am. Soc. Anim. Sci. 53: Kojim, F.N., J.E. Stegner, J.F. Bder, D.J. Schfer, R.L. Ekins, M.F. Smith, nd D.J. Ptterson A comprison of two fixed-time AI progrms for postprtum beef cows. J. Anim. Sci. 81(Suppl. 1):50. Kojim, F.N., J.F. Bder, J.E. Stegner, M.F. Smith, nd D.J. Ptterson. 2003b. A fixed-time AI progrm with 7-11 Synch. J. Anim. Sci. 81(Suppl. 1):51. Lmb, G.C., J.S. Stevenson, D.J. Kesler, H.A. Grverick, D.R. Brown, nd B.E. Slfen Inclusion of n intrvginl progesterone insert plus GnRH nd prostglndin F 2 for ovultion control in postprtum suckled beef cows. J. Anim. Sci. 79: Lrson, J.E., G.C. Lmb, J.S. Stevenson, S.K. Johnson, M.L. Dy, T.W. Gery, D.J. Kesler, J.M. DeJrnette, F.N. Schrick, A. DiCostnzo, nd J.D. Arseneu Synchroniztion of estrus in suckled beef cows for detected estrus nd rtificil insemintion nd timed rtificil insemintion using gondotropin-relesing hormone, prostglndin F 2, nd progesterone. J. Anim. Sci. 84: MFA Helth Trck Progrm Requirements, Muggli-Cockett, N.E., L.V. Cundiff, nd K.E. Gregory Genetic nlysis of respirtory disese in beef clves during the first yer of life. J. Anim. Sci. 70: Perry, G.A., M.F. Smith, nd D.J. Ptterson Evlution of fixed-time rtificil insemintion protocol for postprtum suckled beef cows. J. Anim. Sci. 80: Schfer, D.J., J.F. Bder, J.P. Meyer, J.K. Hden, M.R. Ellersieck, M.F. Smith, nd D.J. Ptterson A Comprison of progestin-bsed protocols to synchronize ovultion prior to fixed-time rtificil insemintion in postprtum beef cows. J. Anim. Sci. 83(Suppl. 1):85. Stegner, J.E., J.F. bder, F.N. Kojim, M.R. Ellersieck, M.F. Smith, nd D.J. Ptterson Fixed-time rtificil insemintion of postprtum beef cows t 72 or 80 h fter tretment with the MGA Select protocol. Theriogenology 61: United Sttes Deprtment of Agriculture. July Ntionl weekly direct slughter cttle premiums nd discounts. St. Joseph, MO, Agriculture Mrketing Service, Report No. LM_CT155: (vrious dtes). 187