Cover combs put to test

But Eyre Peninsula Poll Merino stud breeder Sydney Lawrie, Collandra North, Tumby Bay, believes they may have a place at the opposite end of the temperature scale - hot, dry summers - and prevent sunburn of freshly shorn sheep.

Cover combs have wide gaps between their cutting edges, leaving about two to three weeks of wool growth on sheep.

This offers more thermal protection from adverse weather conditions compared to standard flat combs used in most sheds.

Earlier this month, three shearers shore 260 of Collandra North's young rams in what is believed to be the first on-farm trial using cover combs in the region.

Heiniger Shearing Supplies provided assistance during the shearing, supplying the nine-teeth, 94.5 millimetre-wide Heiniger Crusader combs used, and Australian Wool Innovation lended its expertise.

Sydney, who first saw the cover combs used about 12 months earlier in NSW, believed they could have significant benefits in their warmer climate, especially if the forecasts for more long, hot summers prove right.

"The fibres quite often, when they burn down in the skin, can be damaged, so it (cover combs) gives the sheep the opportunity to have that lanolin to use straight away," he said.

"If we can do something better from an animal welfare perspective by adopting a new shearing option, we really should be trying to do it."

Sydney was pleased with the final result of the shorn rams and hoped to trial the cover combs on his stud ewes in future.

He says shearing during a heat wave has a major effect on their ewes and in such weather, cover combs could keep them in a condition score higher than those in the same flock shorn with flat combs.

"We always shear two months before lambing and so if we can limit the recovery time and the ewes are in better condition score at lambing, it will help our lamb survival and growth rates," Sydney said.

Heiniger SA sales manager Darren McEvoy says the cover combs enter the wool easier than a flat comb, with their long bevel, and if the animals are in good condition are easy to use.

"You do hold the handpiece slightly differently but once you get used to it it takes about the same amount of time to shear," he said.

"We had two shearers in the shed who had never used them, and they soon picked it up."

Darren says the real benefit of using cover combs is at the peak of summer and winter when extra protection from the elements is needed.

"If you know that a huge change in weather is expected, either cold or heat, it is worth shearers and the producer discussing what type of comb might be best," he said.

For a comparison, one of Collandra North's rams was shorn with a flat comb and produced an extra 100 grams of wool than those shorn with cover combs.

AWI shearing industry development coordinator Jim Murray says cover combs are not the "magic bullet" for the sheep industry but another tool to use.

They have been around for "as long as shearing" but their design has significantly improved in recent years.

Although cover combs are mostly used in the New England area of NSW they are slowly being adopted by more shearers in other areas, providing advantages to shearers, growers and sheep.

"For sheep shorn with cover combs there is a tendency to be a little less skin damage so it is less stressful to the animals," Jim said.

"The advantages to the shearer are that they are easier to push through the wool and better for sheep which have a tendency to break the skin because the shearer is up off the skin more.

"And for growers, their sheep certainly go through tough conditions better."

* Full report in Stock Journal, March 27, 2014 issue.