Mid-pregnancy shearing of autumn-lambing ewes in New Zealand
G. deNicolo A , P. R. Kenyon A B , S. T. Morris A , P. C. H. Morel A and A. J. Wall AA College of Sciences, Massey University, Private Bag 11222, Palmerston North, New Zealand.
B Corresponding author. Email: P.R.Kenyon@massey.ac.nz
Australian Journal of Experimental Agriculture 48(7) 957-960 https://doi.org/10.1071/EA07405
Submitted: 10 December 2007 Accepted: 2 April 2008 Published: 20 June 2008
Abstract
The aim of the present experiment was to ascertain if mid-pregnancy shearing of autumn-lambing ewes would increase the birthweight of the lambs. Following pregnancy diagnosis, 123 pregnant ewes were randomly allocated to one of two treatment groups. One group was shorn on day 74 of pregnancy (P74) and both treatment groups were managed as one mob. Ewe liveweights were recorded on day 53 of pregnancy (P53), day 141 of pregnancy (P141), and 45 (L45) and 75 days (L75) after the start of the lambing period. Lamb liveweights were recorded within the first 24 h of birth, L45 and L75. In addition, girth circumference, crown–rump length, fore leg length and rear leg length were measured within the first 24 h of birth. Ewe liveweight, inclusive of the removed fleece, did not differ between treatment groups at P53, P141, L45 or L75. Lambs born to shorn ewes were heavier at birth compared with lambs born to unshorn ewes (P < 0.05; 4.56 v. 4.24, respectively), but not at L45 or L75. Girth circumference (P < 0.01), crown–rump length (P < 0.05) and fore leg length (P < 0.01) were also longer in lambs born to shorn ewes. It was concluded that ewes shearing ewes in the summer–autumn period can be used as a means of increasing lamb birthweight.
Acknowledgements
The authors wish to thank Massey University, Meat and Wool New Zealand and the C. Alma Baker Trust for financial support.
Cam MA, Kuran M
(2004) Shearing pregnant ewes to improve lamb birth weight increases milk yield of ewes and lamb weaning weight. Asian-Australasian Journal of Animal Sciences 17, 1669–1673.
[Verified 8 April 2008]
Revell DK,
Morris ST,
Cottam YH,
Hanna JE,
Thomas DG,
Brown S, McCutcheon SN
(2002) Shearing ewes at mid-pregnancy is associated with changes in fetal growth and development. Australian Journal of Agricultural Research 53, 697–705.
| Crossref | GoogleScholarGoogle Scholar |
Sasaki Y, Takahashi H
(1980) Insulin secretion in sheep exposed to cold. The Journal of Physiology 306, 323–335.
|
CAS |
PubMed |
Sherlock RG,
Kenyon PR,
Morris ST, Parkinson TJ
(2003) Metabolic changes in ewes shorn during mid-pregnancy. Proceedings of the New Zealand Society of Animal Production 63, 144–148.
Symonds ME,
Bryant MJ, Lomax MA
(1986) The effect of shearing on the energy metabolism of the pregnant ewe. The British Journal of Nutrition 56, 635–643.
| Crossref | GoogleScholarGoogle Scholar |
CAS |
PubMed |
Symonds ME,
Bryant MJ,
Shepherd DAL, Lomax MA
(1988) Glucose metabolism in shorn and unshorn pregnant sheep. The British Journal of Nutrition 60, 249–263.
| Crossref | GoogleScholarGoogle Scholar |
CAS |
PubMed |
