Last update: August 16, 2011 11:16:47 AM E-mail Print

ALTERNATIVE WEANING PRACTICES SUGGESTED

PR King

 

New information indicates that there is little value in the practice among Angora goat farmers of swopping ewes to reduce the stress of weaning. This is the contention of Mr Paul King, animal production researcher at the Grootfontein College of Agriculture.

This finding was made during experiments conducted at Grootfontein and the Angora goat research station at Jansenville.

It is a well-known fact that a large percentage of young goats grow poorly after weaning. After goats are weaned under normal Karoo conditions, it can take up to 5 months before they regain their weaning mass.

According to Mr King, this poor growth gives rise to various problems for the Angora goat industry. The low lambing percentages of two-tooth ewes obtained by farmers can largely be attributed to the fact that the ewes do not reach at least 27 kg before mating, owing to poor growth after weaning.

 

Considerably higher

A further problem, which ostensibly is largely the consequence of this poor  growth after weaning; is the high mortality which occurs between weaning and two-tooth age. A survey among Angora goat farmers has revealed that losses during this period amount to 12,5 %, which is considerably higher than losses experienced by other small stock breeds.

The effect of weaning stress on growth after weaning was investigated by Mr King as a possible cause of poor growth.

During experiments under veld conditions, it was found that daily mass gain of weaned goats was 10,2 g/day as against the 12,4 g/day of goats whose mothers were swopped.

The control group, which was not weaned, showed an average daily mass gain of 34 g/day - that is, three times more than the weaned and swopped groups.

It would thus appear that weaning does indeed have an inhibiting effect on post-weaning growth and that the practice of swopping ewes at weaning time holds no advantages.

 

Unexplained

Mr King points out another very important unexplained observation in respect of growth after weaning. The average daily mass increase of ram and ewe Iambs is the same when they are not weaned. When they are weaned or swopped, the ram Iambs show a daily growth three times better than that of the ewe Iambs.

The average daily increase of the weaned ram Iambs was 28 g/day compared to the 9,4 g of the weaned ewe Iambs, while the daily increase of the unweaned ewe Iambs was 35,4 g/day.

In practice it would be advisable not to wean the ewe Iambs at the same time as the ram Iambs, but rather to wean them at 7 months of age just before the next mating season. During the experiments it was confirmed that the ewes had weaned their Iambs naturally at 5½ months.

Should farmers be compelled to wean Iambs because of other considerations, it is important that the weaned ewe Iambs receive supplementary feed to ensure an acceptable growth rate after removal from their mothers.

 

Published

Karoo Regional newsletter 2