Vet against norm in leaving tails intact

Wanganui veterinarian David Rankin flies in the face of tradition by leaving the tails of his 220 lambs intact.

There are two main methods of docking lambs' tails, and much debate about how much to take off.

Mr Rankin says a large and unstitched wound on a young animal will slow its growth and is better avoided. He leaves the tails on lambs he sends to the works.

A young lamb on its mother should be growing 200g to 300g a day, he said. If it stops growing for 10 days while the wound heals that could cost more than 1.5kg in weight gain, which could be worth $10. Lambs that gain weight and are sold earlier fetch higher prices.

Most cut the tails too short, Mr Rankin says. The tail should cover a female lamb's vulva, with the equivalent length for a male lamb.

Sheep raise their tails when they defecate, and a longer tail raises the skin around their anus, so that any loose faeces are directed away from their bodies. Faeces that run down and stick in their wool can attract fly strike.

There are two usual ways of removing lambs' tails. One is by putting a rubber ring around the tail which cuts off blood supply until the tail dies and drops off. It takes about two weeks.

The advantage in that method is that the dying tails can be sprayed with fly repellent, protecting the sheep from fly strike.

The other, and usual, way is to cut off the tails with a large, hot blade. Lambs can bleed to death from the large wound. Flies are attracted to it as it heals, and repellent sprayed on it will not stick. It can also become infected.

Lamb survival is good this year but final numbers in Wanganui could be at least 5 per cent down, Mr Rankin said.

The drought last season meant ewes were in poorer condition than usual and carrying fewer lambs. But high survival rates may make up for the smaller number of births.

The high survival was mainly due to plenty of feed for the lactating ewes. Mr Rankin said feed counted for more than mild temperatures.

The region was drier than usual up until September 20. After a week's regular rain grass growth was taking off again.

Mr Rankin predicts the combined effect of plentiful feed and extra animals killed off last year will hike the prices of hill country sheep and cattle bought for fattening at the coast.

Hill country farmers had to sell or kill more sheep and cattle than usual during the drought because they couldn't feed them.

And with plenty of grass they are more likely to keep their lambs longer. By growing them to 22kg rather than 18kg they will get higher prices.

People putting in crops ready to fatten lambs need to brace themselves. "The only way you can draw them out of the hills is to pay more for them," Mr Rankin said.

He says the cattle fairs after Christmas will be lucrative.