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Production in mature corriedale ewes first mated at 7 to 11 or 18 months of age

Published online by Cambridge University Press:  02 September 2010

R. W. Ponzoni ,
M. Azzarini  and
S. K. Walker
R. W. Ponzoni
Affiliation:
Estacion Experimental Dr M. A. Cassinoni, Paysandu, Uruguay
M. Azzarini
Affiliation:
Estacion Experimental Dr M. A. Cassinoni, Paysandu, Uruguay
S. K. Walker
Affiliation:
Estacion Experimental Dr M. A. Cassinoni, Paysandu, Uruguay
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Abstract

Production in 210 mature Corriedale ewes first mated between 7 and 11 or at 18 months of age was studied at Paysandu, Uruguay. Ewes were classified into one of the following five classes according to their oestrous and lambing performance in 1968: (1) reared a lamb; (2) lambed but lamb died; (3) mated but did not lamb; (4) oestrus detected by vasectomized ram, true mating deferred for 12 months; and (4) no oestrus, mating deferred for 12 months. Records on flock performance and mortality were kept from all ewes from 1969 to 1973, when the dental status of all ewes present was assessed.

There were no significant differences between classes in number of ewes lambing per ewe exposed to the ram, number of lambs born per ewe exposed to the ram, number of lambs weaned per ewe exposed to the ram, weight of lamb weaned per ewe exposed to the ram, and pre-mating body weight.

Greasy fleece weight varied significantly (P < 0·01) with class of ewe. The least squares means for ewe classes 1 to 5 were 3·93, 3·99, 4·06,4·12 and 3·92 kg respectively. Class 4 ewes differed significantly (P < 0·01) from class 1 ewes and from class, 3 and 5 ewes (P < 0·05). Class 3 ewes differed significantly (P < 0·05) from class 1 ewes. Other differences were not significant.

Ewe mortality between 1969 and 1973 was independent of class of ewe. The dental status of ewes appeared to vary with class of ewe. Early mating of Corriedale ewes apparently had no adverse effects on mature reproductive performance, but somewhat reduced wool production. If mating is to take place for the first time at 18 months of age, ewes that have shown oestrus previously are likely to exhibit greater overall productivity (wool plus lambs).

Type
Research Article
Information
Animal Production , Volume 29 , Issue 3 , December 1979 , pp. 385 - 391
Copyright
Copyright © British Society of Animal Science 1979

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References

REFERENCES

Azzarini, M., Cardellino, R., Gaggero, C, Nicola, D., Oficialdegui, R. and Rodriguez, A. 1975. Relevamento basico de la production ovina en el Uruguay 1972/1973. Secretariado Uruguayo de la Lana, Montevideo, Uruguay.Google Scholar
Baker, R. L., Steine, T. A., Vabeno, A. W., Bekken, A. and Gjedrem, T. 1978. Effect of mating ewe lambs on lifetime productive performance. Acta Agric. scand. 28: 203–217.CrossRefGoogle Scholar
Briggs, H. M. 1936. Some effects of breeding ewe lambs. JV. Dakota agric. Exp. Stn Bull., No. 285.Google Scholar
Cannon, D. J. and Bath, J. G. 1969. Effect of age at joining on life-time production by Border Leicester × Merino ewes. Aust. J. exp. Agric. Anim. Husb. 9: 477–481.CrossRefGoogle Scholar
Dýrmundsson, Ó R. 1973. puberty and early reproductive performance in sheep. i. ewe lambs. anim. breed. abstr. 41: 273–289.Google Scholar
harvey, W. R. 1972. Least-squares and maximum likelihood general purpose program. Ohio State University (Mimeograph).Google Scholar
Hight, G. K. and Jury, K. E. 1976. Hill country sheep production. VIII. Relationship of hogget and two-year-old oestrus and ovulation rate to subsequent fertility in Romney and Border Leicester × Romney ewes. N.Z. Jl agric. Res. 19: 281–288.Google Scholar
Hulet, C. V., Wiggins, E. L. and Ercanbrack, S. K. 1969. Estrus in range lambs and its relationship to lifetime reproductive performance. J. Anim. Sci. 28: 264–252.CrossRefGoogle Scholar
Keane, M. G. 1974. Effect of previous lambing on body weight and reproductive performance of hoggets. Ir. J. agric. Res. 13: 191–196.Google Scholar
Levine, J. M., Vavra, M., Phillips, R. and Hohenboken, W. 1978. Ewe lamb conception as an indicator of future production in farm flock Columbia and Targhee ewes. J. Anim. Sci. 46: 19–25.CrossRefGoogle Scholar
Omar, I., Jordan, C. and Smith, C. 1977. A note on effects of lambing at 1 year and farm production level on the performance of prolific ewes. Anim. Prod. 25: 389–392.Google Scholar
Ponzoni, R. and Azzarini, M. 1968. Estacion de cria y eficiencia reproductiva de borregas Corriedale diente deleche. Boln tec, Estac. ExplPaysandu, Uruguay 5: 79–110.Google Scholar
Steine, T. A. 1974. [The effect of lambing at 1 year of age on production traits in sheep.] Meld. Norg. LandbrHoisk. 53: No. 11.Google Scholar
Suiter, R. J. and Croker, K. P. 1970. Mating weaners does not affect future ewe performance. J. Agric. West. Aust. 11: 92.Google Scholar
Tyrell, R. N. 1976. Some effects of pregnancy in eight-month-old Merino ewes. Aust. J. exp. Agric. Anim. Husb. 16: 458–461.CrossRefGoogle Scholar
Tyrell, R. N., Fogarty, N. M., Kearins, R. D. and McGuirk, B. J. 1974. A comparison of the subsequent production by Border Leicester × Merino ewes first joined as weaners or at 18 months of age. Proc. Aust. Soc. Anim. Prod. 10: 270–273.Google Scholar
Vavra, M., Hohenboken, W. and Phillips, R. L. 1978. Reports on breeding ewe lambs. I. The influence of age at first lambing on ewe production and longevity. Spec. Rep. 502, Agric. Exp. Stn, Oregon St. Univ., Corvallis, USA.Google Scholar