Development of a self-drafting system for oestrus ewes

L.R. Matthews, A.E. Uljee, K.J. Bremner, A.M. Painting, L.R. Cate, J.F. Smith

Ruakura Agricultural Centre, MAF Technology, Hamilton, New Zealand

Proceedings of the New Zealand Society of Animal Production. 1991, 51: 315-318

An efficient farm AI system for sheep requires ready identification of, and access to, oestrus ewes. It is well known that ewes in oestrus seek out and remain near rams. The present experiment evaluated a variety of systems for trapping oestrus ewes attracted to two decoy rams.

These systems included traps with one or two entrances, and traps sited 1.5 or 6 m from the rams. In each trial, 13 to 16 ewes in a flock of 45 mixed age and mixed breed sheep were artificially induced into oestrus and the proportions of oestrus ewes entering the trap was recorded. In addition, the trapping rate in a flock of naturally cycling 1‡ yr and 2‡ yr ewes was assessed.

Over all trials, half of the animals in oestrus were trapped. Trap configuration had no significant effect on catch rate. Trapping rates for two-tooth (primiparous) and four-tooth sheep were similar.

A trap system has been developed which attracts and captures a significant proportion of oestrus ewes. The catch rate is sufficiently high for practical use in farm AI programmes.

Keywords: NZSAPAB; Oestrus ewes; ram-seeking; self-drafting; trapping; behaviour; sheep

Download abstract in text format
Last Updated 25-01-1997