Can. J. Anim. Sci. Downloaded from by on 03/31/18

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1 COMPARISO OF ATURAL MATIG AD ARTIFICIAL ISMIATIO O RPRODUCTIV PRFORMAC OF THR STRAIS QF SHP HOUSD I TOTAL COFIMT A. J. HACKTT1 and M. S. WOLYTZ2 Can. J. Anim. Si. Dwnladed frm by n 03/31/18 tanimal Researh Centre, ATriuhure Canada, Ottawa, Ontari KtA0C6; and 2Statistial Researh Setin. ngineering antl Statistial Researh Institute, Agriulture Canada, Ottawa, Ont. KIA 0C6. Cntributin ns. 888t and I-1482, reeived 28 Jan. 1981, aepted 25 June I98l. Hererr, A. J. a Wr-vnr, M S Cmparisn f natural mating and artifiial inseminatin n reprdutive perfrmane f three strains f sheep hused in ttal nfinement. Can. J. Anim. Si. 6l: The reprdutive perfrmane (fertility, prlifiay and feundity) f nfined sheep was measured fllwing natural mating r artifiial inseminatin (AI) with 0.1 ml f unextended semen lleted by nrtifiial vagina r by eletrejaulatin. The estrus yles f the ewes were synhrnied in late summer using intravaginal spnges impregnated with flurgestne aetate. Pregnant mares' serum gnadtrphin (PMSG) was administered intramusularly t apprxirnately half f the ewes. There was n signifiant differene in the reprdutive perfrmane f ewes bred by natural mating (457) r Al (3O) r between the tw methds f semen lletin (30 vs. 29V). Fertility was greater (P<0.05) in ewes treated with PMSG (33 vs.llv) mainly beause f a tendeny fr higher fertility in ewes bred by AI. PMSG als signifiantly (P<0.01) inreased prlifiay and feundity, 1.8 vs. 1.5 and 58 vs. l6va, respetivell'. Les aptitudes reprdutries (f'ertilit6, prlifiit6 et f6ndit6) de mutns en laustratin nt 6t6 mesurdes aprds saillie naturelle u insdminatin artifiielle (ta) par 0.1 ml de sperme nn dilu6 pr6lev6 par la m6thde du vagin artifiiel u de l'6letr6jaulatin. Les yles estiaux des brebis nt 6td synhrnis6s ) la fin de l'6t6 au myen d'6pnges intravaginales impr6gn6es d'a6tate de flurgestne. On a administr6 de la gnadtrphine s6rique de juments gravides (PMSG) par vie intramusulaire d la miti6 des brebis envirn. On ne nstate auune diff6rene signifiative dans la perfrmane reprdutriedes brebis sailliesnaturellemenl(45v) uparla (30%),ni entrelesdeux m6thdes de pr6ldvement du sperme (30 ntre 297). Laferlilit6 des brebis trait6es d la PMSG (33 ntre I lva) est plus grande du fait que l'ins6minatin a tendane d I'aritre. L'administratin de PMSG arit aussi la prlifiitd et la f6ndit6 de faqn signifiative, sit 1.8 ntre 1.5 et 58 nlre l6va respetivement. In a ntrlled breeding prgram fr sheep, urently being used (Grdn 1915, 1917; many f the advantages f using artifiial Rbinsn 1965,1976;ThimnierandCgnie inseminatin (AI) depend upn the ntrl f 1977). Fllwing synhrniatin f estrus, estrus andvulatin (Clas 1975). Suessful rams in a rati f l:10 were jined with the prgrams develped fr synhrniing estrus ewes fr natural mating 48 h after spnge in sheep under varying physilgial states, remval and PMSG injetin (Grdn 1963, using plyurethane intravaginal spnges im- 1977)._ln ewes synhrnied fr estrus, 500 pregnated with flurgestne aetate (FGA) x 10" spermata have been inseminated and intramusular (IM) injetins f pregnant twie between 50 and 60 h after spnge remares' serum gnadtrphin (PMSG), are mval and PMSG injetin (Clas 1975; Grdn 1971, l9ll). When ewes were syn- Can. J. Anirn. Si. 6l: 907*912 (Deember 1981) hrnied fr estrus and inseminated with 90'7

2 908 CAADIA JOT,'RAL OF AIMAL SCIC Can. J. Anim. Si. Dwnladed frm by n 03/31/ ml unextended semen lleted by eletrejauiatin (), mre than 507 lambed (Rbinsn 1956). The ratinale fr establishing a ntrlled breeding prgram fr sheep hused year rund in ttal nfinement in a ntrlled envirnment has been reprted (Heaney et al. 1980). A prgram using synhrniatin f estrus and Al tehniques, already used in less intensive systems, has been established (Hakett et al. 1979). The purpse f this study was t mpare the reprdutive perfrmane f naturally bred sheep with that f artifiially inseminated sheep hused in ttal nfinement in whih estrus was synhrnied during late summer. At the same time the methd f semen lletin (artifiial vagina (AV) versus eletrejaulatin (), PMSG treatment, ram age and strain f sheep were evaluated. MATRIAL AD MTHODS Sheep used in this experiment were hused in ttal nfinement and were frm three syntheti strains (Sire, Dam I and Dam 2) being develped at the Animal Researh Centre (Hakett et al. 1979). Fr the 4 m prir t the start f treatment. 54 rams (7 m-3 yr f age at the time f breeding) and 39 I ewes ( 1-6 yr f age at the time f breeding) were maintained under a lighting regime f l0 h light:14 h dark t indue yling in rhe ewes (Duker et al. 1970). In late August 1974, during the late anestrus r early estrus seasn. ewes were treated with 40 FGA (Chrn-gest, Intervet S.A., Angers, Frane 49024) impregnated in intravaginal plyurethane spnges that were left in plae fr l2 days (Hakett et al. 1979). At the time f spnge remval, ne half f the ewes reeivd 500 IU PMSG (quinex, Ayerst Labratries, Divisin f Ayerst, MKenna and Harrisn, Ltd.. Mntreal, Quebe H3C 3Jl) IM. Fr natural mating, 34 rams (7 m-3 yr f age at the time f breeding) were plaed individually in pens with a grup f nine ewes n the day f spnge remval; 23 days later the rams wel'e rt:, mved. All ewes ame int estrus within 48 h after spnge remval. Training f 20 rams (l-3 yr f age) t serve an AV began in July. Only srx rams (fur frm the Sire and ne frm eah f the Dam I and Dam 2 strains) were willing t serve an AV n the day f breeding. Semen frm six ther rams, the distributin within strains rrespnding t that abve, was lleted by ; thus there was an imbalane in the experimental design between the number f rams serving thrugh natural mating and the number used in eah f the AI methds. The semen was kept in a warm pket until inseminated between 10 and t5 min after lletin. ah sample was mirspially examined fr rate f mtility and perentage live spermata. Only samples that had a mtility rate f at least 4 n a sale f G5, as used fr evaluating bull semen (Swansn and Herman 1944), and at least 707 live spermata were inseminated. wes were inseminated twie with 0. I ml f unextended semen, apprximately 500 x 106 spermata, at 48 and 60 h after spnge remval. Using a stainless-steel inseminating rd (45 mm, 12 gauge), semen was plaed as far frward as pssible int the ervix. The rati f ewes t rams was 9:1 similar t that f natural mating. Any ewe nt neivrng t servie at the synhrnied estrus had an pprtunity t be bred at a subsequent estrus. Fr ewes assigned t AI, the apprpriate rams were penned with the ewes 5 days after AI fr a perid f 16 days. Only data frm sheep frm whih spnges were remved. and whih were alive at the end f the gestatin perid were inluded in the analyses. The data were analyed fr fertility (number f ewes lambing per 100 ewes expsed t rams r bred by AI). prlifiay (number f lambs brn per ewe lambing) and feundity (number f lambs brn per 100 ewes expsed t rams r bred by AI) fr the synhrnied estrus, based upn lambing less than 154 days after spnge remval. Althugh these variables are disrete and nt nrmally distributed, prbability levels btained by analying suh data by analysis f variane shuld apprximate the rret prbability levels (Gabriel 1963;Li 1964). Beause there were data frm nly ne ram in eah f the Dam strains fr eah f the semen lletin methds, nly the Sire strain data were used t mpare reprdutive perfrmane under either natural mating r AI. A split plt mdel, with pens f ewes as the whle plts, was used t analyse these data. The whle plt fatrs were methd f breeding (natural mating, Al with semen lleted by AV, AI with semen lleted by ) and ram age ((yr r =1 yr), and the within plt fatr was PMSG appliatin. All first-rder interatins were inluded in the mdel. T btain mre infrmatin n the effet f PMSG and t evaluate strain differenes. the data

3 HACKTT AD WOLYTZ RPRODUCTIV PRFORMAC OF SHP 909 frm the naturally mated ewes in all three strains were analyed. Again, a split plt mdel was used with the whle plt fatrs being strain and ram age, and the within plt fatr being PMSG appliatin. All first-rder interatins amng these fatrs were inluded in the mdel. Results were nsidered t be statistially sienifiant whenever P<0.05. e' q 3 -rk F I + f - O@d i-- -O h -h Can. J. Anim. Si. Dwnladed frm by n 03/31/18 RSULTS AD DISCUSSIO Only 25 f 104 Sire strain ewes lambed (Table I ). Fr fertility, there was a signifiant ram age by PMSG interatin. The fertility f ewes reeiving PMSG and mated t lder rams (58%) was signifiantly higher rhan the fenility f ewes nt reeiving PMSG and mated t lder rams (l5%), r the fertility f ewes with r withut PMSG and mated t yung rams (8%). Fertility was smewhat higher in Sire strain ewes reeiving PMSG and artifiially inseminated than in thse nt reeiving PMSG and artifiially inseminated (Table 2). This is nsistent with ther data indiating that PMSG shuld be adminstered t ewes treated with FGA and mated by Al even during the breeding seasn (Clas r97s). Of the 251 ewes mated naturally, ll7 lambed (Table 3). There were n signifiant effets due t strain, ram age, PMSG r their interatins. The fertility was smewhat lwer than the range f btained frm mature ewes treated in the late anestrus seasn with FGA and PMSG (ewtn 1969; O'Reilly 1979). Althugh PMSG may have inreased fertility in Sire strain ewes, partiularly thse bred t lder rams, this same pattem was nt bserved fr the Dam 2 ewes (Table 2). The lwer fertility in the Sire strain was mainly due t the inability f the sexually inexperiened yung rams t breed the ewes synhrnied fr estrus (Table 2). This finding is similar t that frm a previus experiment with sheep hused in ttal nfinement in whih the yung rams in the Sire strain failed t breed ewes in estrus while thse yung rams in the tw dams strains dil s (Hakett et al. 1979). Fr the Sire strain. there were n signifiant effets in prlifiay due t mat- I F =,i _ F =a >= O q ':t Z aia - Z a 5 3-, Sh hh 3 f 9': "f - -+ n r 6+ n@ h) n) d d O C <O -- O -O 3 9Rg Sa f;il 6 2frl +F.-Y <tr VAr >H af hx J,^9. tr:vf J:: 3 d> ai 0<. 9P q* = itr Yq 7'r '6. 5 a - l4?.a p 9P Y6- H9" q9

4 910 CAADIA JOURAL OF AIMAL SCIC Table 2. Observed means fr fertility (%) and the numbers f ewes and rams invlved by age r ram, PMSG treatment, strain f sheep and mating methd. Can. J. Anim. Si. Dwnladed frm by n 03/31/18 PMSG il (1 yr treatmenl 5OO IU Age f ram. f rams Strain and Mating Methdf Sire Sire Sire Dam I Dam 2 ll(19) 0( s) 40( l 0) 40(15) 12(.17)-1 2s( 4) 60( s) 3106) 5 0 I 2 j t signifies natural mating, AV and signify semen lleted by respetively. fumbers in parentheses indiate the number f ewes expsed. ing methd, ram age r PMSG treatment (Table 1). Prlifiay was signifiantly greater fr naturally mated ewes treated with PMSG (2.0) than fr thse untreated (1.5) (Table 3). Primarily as a funtin f the bserved fertility pattem, the feundity f Sire strain ewes given PMSG (587) was signifiantly greater than that f ewes nt given PMSG (l6v) (Table l). Als, the feundity f ewes bred t lder rams (537) was greater than that f ewes bred t yung rams (.21V). As a result f the greater prlifiay fr naturally mated ewes treated with PMSG, feundity, a measure f verall prdutivity, was als signifiantly greater fr ewes treated with PMSG and mated naturally (Table 3). Bth the Dam I and Dam 2 strains were mre prlifi than the Sire sffain. Despite the smewhat lwer fertility, the results f breeding ttally nfined sheep in the late summer seasn were very enuraging. This was the first attempt t breed a large number f sheep hused in this speifi ntrlled lighting envirnment using hrmnes t synhrnie estrus. Interpretatin f the results must be made with autin beause f the numerus fatrs invlved. Fr example, the nature fthe phtperidi atin appears t be mplex (Maulen and Ruget 1962). In their study, there was a breed by envirnment (lighting) interatin. The interval frm PMSG il 2s( 4) u(12) 0(12) 43(40) 66G4\ >1 yr. treatment f 500 IU rams 80( s) 4t(17) 5s(1 l) s6(39) 60(37) I t1 artifiial vagina r by eletrejaulatin, the lngest day t first estrus was lnger in the bi-annual lighting regime (light:dark relatinships ndensed int 6 m) than in the annual lighting regime fr sheep f the Prealpes du Sud and Limusine breeds, whereas it was the same fr Texel ewes, whih nrmally have shrt perids f sexual ativity. In the present study, the lighting regime was designed t indue estrus yle ativity in ewes within 40 days pstpartum and appeared t be effetive. Hwever, by superimpsing the hrmnal treatment, FGA either with r withut PMSG, estrus uld be either indued r synhrnied depending upn the initial physilgial status f the ewe at the initiatin f treatment. Others have reprted innate seasnal effets in ewes kept under ntrlled lighting envirnments (Rbinsn et al. 1975). In this latter experiment, the lighting regime and hrmnal treatments were different t thse in the present experiment. In nlusin, the present study had demnstrated that satisfatry reprdutive perfrmane f ttally nfined sheep an be btained by using a ntrlled lighting envirnment in njuntin with hrmnal treatments. ither natural mating r AI may be used prvided sexually experiened rams r semen f gd quality are used. PMSG is neessary when AI is used.

5 HACKTT AD WOLYTZ RPRODUCTIV PRFORMAC OF SHP 91 1 Can. J. Anim. Si. Dwnladed frm by n 03/31/18 ' tr tr =- J F r - g.l a -P. br,: '9p J -9 -n n nt -+a- d d d - C- d r h r O +@ h -: =es I h -:j- -6O * r + -t+ - n t i + n$ d *6- d a TI Zq : 9-a > -AA V & - -7 O a9 ; 6 ; * :q qa +-+ ACKOWLDGMTS The authrs wish t thank J. F. Hunter, J. Arand and the sheep staff fr aring fr the sheep, Drs. L. Ainswrth and D. P. Heaney fr inseminating the ewes and Miss J. M. Llyd-Smith fr lleting the semen. The authrs appreiate the advie and enuragement extended by Dr. H. F. Peter. COLAS, G The use f prgestagen SC9880 as an aid fr artifiial inseminatin in ewes. Ann. Bil. Anim. Bih. Biphys.llt DUCKR, M. J., THWAITS, C. J. and BOW- MA, J. C Phtperidism in the ewe. 1 The effets f varius patterns f dereasing daylengths n the nset f estrus in Clun Frest ewes. Anim. Prd. 12: ll5-123 GABRIL, K. R Analysis f variane f prprtins with unequal frequenies. J. Amer. Statist. Ass. 58: ll GORDO, l The use f prgestagens in sheep bred by natural and artifiial inseminatin. Ann. Bil. Anim. Bih. Biphys. 15: GORDO, I Appliatin f synhrniatin f estrus and vulatin in sheep. Management f reprdutin in sheep and gats. Sympsium, Univ. f Wisnsin, Madisn, Wis. July 24-25, pp HACKTT, A. J.,ISKP,. K., ROBRT. SO, H. A., SHRSTHA, J.. B. and WOLYTZ, M. S Cmparisn f artifiial inseminatin and natural mating n reprdutive perfrmane f five strains f sheep during the anestrus seasn in an intensive system. Can. J. Anim. Si FIAY, D. P., AISWORTH, L., BATRA, T. R., FISR, P. SL., HACKTT, A. J., LAG- FORD. G. A. and L. A. J Researh fr an intensive ttal nfinement sheep prdutin system. Agri. Can. Anim. Res. Inst. Teh. Bull pp. LI, J. C. R Statistial inferene I (revised ed.). dward Brs. In., Ann Arbr, Mihigan. pp. 45G457. MAULO, R. and ROUGOT, J Regulatin des saisns sexuelles he des br6bis de raes diffdrentes au myen de divers rythmes lamineux. Ann. Bil. Anim. Bih. Biphys. 2: 209:222. WTO, J Mdern aspets f reprdutin in sheep. Teh. Rept.. 7, Grasslands Researh Institute. Hurlev.

6 9t2 CAADIA JOURAL OF AIMAL SCIC Can. J. Anim. Si. Dwnladed frm by n 03/31/18 O'RILLY, P. l Fertility resulting frm A.I. r natural mating using pessaries r implants t synhrnie estrus in ewes. Pr. 7th Int. Cngr. Animal Rprdutin and Artifiial Inseminatin (Munih). 2: 939. ROBISO, J. J., FRASR, C. and MHAT- TI. I The use f prgestagens and phtperidisrn in imprving the reprdutin rat f th ewe. Ann. Bil. Anim. Bih. Biphys. 15: ROBISO. T. J The artifiial inseminatin f the Merin Sheep fllwing the synhrniatin f estrus and vulatin by prgesterne injeted alng with pregnant mar serulr gnadtrphin (PMS). Aust. J. Agri. Res. 7: ROBISO, T. J Use f prgestagen impregnated spnges inserted intravaginally r subutaneusly fr the ntrl f the estrus yle in the sheep. ature (Lnd.) ROBISO, T. J. 19'76. Cntrlled breeding in sheep and gats. In G. J. Tmes, D.. Rbertsn and R. J. Lightft, eds. Pr. Int" Sheep Breed. Cngr. Muresk lnstrtute f Tehnlgy, W. Australia. SWASO.. W. and HRMA, H. A The rrelatin between sme harateristis f dairy bull semen and neptinrate. J. Dairy Si. 27t 29' THIMOIR, J. and COGI, Y Appliatin f ntrl f reprdutin f sheep (in Frane). Management f Reprdutin in Sheep and Gats Sympsium, University f Wisnsin, Madisn, Wis. July 24-25, pp

7 This artile has been ited by: Can. J. Anim. Si. Dwnladed frm by n 03/31/18 1. M.K. Shmehl, S.P. Andersn, I.A. Vaque,.F. Graham The effet f dialysis f extended ram semen prir t freeing n pst-thaw survival and fertility. Crybilgy 23:5, [Crssref] 2. A.J. Hakett, M. Hidirglu ffets f PMSG n prgesterne levels in ewes treated with flurgestne aetate r prstaglandin F2α. Animal Reprdutin Siene 6:3, [Crssref] 3. A.J. Hakett, M.S. Wlynet ffet f PMSG n the reprdutive perfrmane f ttally nfined ewes bred at synhrnied estrus. Therigenlgy 17:2, [Crssref]