Neonatal recognition in sheep
Date
2013
Authors
Burger, B. V.
Viviers, Marlize Z.
Le Roux, Niel J.
Morris, John
Bekker, Jan P. I.
Le Roux, Maritha
Journal Title
Journal ISSN
Volume Title
Publisher
Springer New York
Abstract
The strong bond formed between ewe and lamb shortly after parturition is
an important factor in lamb survival. Evidence exists that the ewe can distinguish her
lamb by its unique smell, but the constituents of such a putative pheromone have not
yet been identified. We have identified 133 volatile organic compounds in the cranial
wool of Dohne Merino lambs that are presumably constituents of the neonatal recognition
cue of this sheep race. Quantitative analysis and comparison of the odour
profiles of the twins of 16 ewes of a flock of 165 twin-bearing ewes (9 .69% sample
group) revealed that the wool volatiles of twins are qualitatively as well as quantitatively
practically identical, but differ from those of other twins or non-twin lambs in
the flock. The 88 constituents present in at least 20% of the analysed wool samples
were considered as variables for multivariate analysis. A ?-value <0.0001 was calculated,
indicating that the pairing of twins according to the qualitative and quantitative
composition of the wool is statistically highly significant. Bioassays carried out during
the lambing seasons of 2009 and 2010 confirmed the previously established role
of the odour of lambs in ewe-lamb recognition. However, ewes rejected alien lambs
dressed in jackets that were sprayed with mixtures formulated with synthetic analogues of the identified wool volatiles according to the qualitative and quantitative compositions
of the experimental ewes' own lambs. This is probably due to the volatiles not being
released into the atmosphere in quantitative ratios emulating the odour of the lambs
accurately enough to satisfy the experimental ewes.
Description
The original publication is available at http://link.springer.com/chapter/10.1007%2F978-1-4614-5927-9_5 but only in print format
Keywords
Olfactory cues, Ewe and lamb, Fostering in sheep, Volatile organic compounds
Citation
Burger, B. V. et al. 2013. Neonatal recognition in sheep. In East, M. L. & Dehnhard, M. (eds.), Chemical Signals in Vertebrates XII (pp. 61-75). Springer New York, doi:10.1007/978-1-4614-5927-9_5.