Thursday, July 7, 2022

All breeds at risk of defects

Hereford breeders have also been given a reminder about the risk of genetic defects in their cattle, New Zealand association president Philip Shepherd says.

Angus NZ’s recent memo to members about the legal risk of failing to disclose potential genetic defects in sale stock could also apply to all sorts of animals, Shepherd said.

“Basically, most breeds of whatever species you’d like to talk about have recessive genes that cause problems.

We’ve got one (hypertrichosis) that we’ve been dealing with for the last two to three years. Then there’s two more that we’ve been testing for the last 12 months but we haven’t actually found a carrier animal in NZ.”

CAN DO MORE: Lincoln University geneticist Jon Hickford says it is fair to ask whether sheep and beef breeders are doing enough to act on possible genetic defects, in stock management or marketing.

The latter couple of problem genes are the diluter, which affects colour and coat formation, and idiopathic epilepsy, a fatal condition in Herefords that causes calves to die soon after birth.

The defects were present overseas and would be noted in Hereford sale catalogues if they were found in NZ, Shepherd said.

Any recorded cattle were tested. To deal with hypertrichosis it had been compulsory in the past 12 months for any transferred bull to be tested.

“And we’ve tacked on these other two (voluntary) tests, basically free, so everything is getting tested for these three things.”

Since the Angus story (Farmers Weekly, June 15), NZ Hereford had emailed its members, reminding them about stock management messages they had been given over the years, Shepherd said.

“It is important to understand the implications of genetic abnormalities across all breeds,” the association said in one email.

Shepherd said no matter the problem, there was always risk of a bull failing to live up to a buyer’s expectations.

If there was no reason to suspect a genetic defect, there was almost always agreement a faulty animal would be returned to the vendor and the purchase refunded if there were problems, he said.

“If it’s not been tested prior to sale it’s an unwritten agreement and I don’t think you’d find any sellers that wouldn’t stand by it and refund the money.”

Defects were likely to cause the most problems if they appeared in the middle of a selling season, possibly leaving buyers starved of alternative options.

Shepherd said breeders and buyers would probably want to know more about the status of animals now.

“It’s an interesting thing – it’s not something that’s just arrived. I’ve had (Hereford) breeders who’ve seen these things, you know, 50 years ago.”

Shepherd started delving into that history once his association initiated testing for hypertrichosis, which can turn a coat light and curly.

Breeders remembered calves looking like that in the 1960s, before the widespread arrival of North American bloodlines.

The modern mix of local and imported bloodlines could be expected to increase the risk of genetic defects coming into the country, he said.

“It is important to understand the implications of genetic abnormalities across all breeds.”

New Zealand Hereford Association

“It mixes with whatever you’ve got and bingo, out it comes – you get a double copy of the gene.”

Hypertrichosis affects only purebred stock, whereas the diluter gene appears in crossbreds.

Bull farmers relying on income from dairy farmers buying crossbreds would be relieved the diluter gene hadn’t been identified, Shepherd said.

While a $25 a head test was a cost a breeder should be able to bear, margins were often tight already and some operators would take the risk of doing without it, he said.

Lincoln University geneticist Jon Hickford said it was fair to ask whether sheep and beef breeders were doing enough to act on possible genetic defects, in stock management or marketing.

His Lincoln division runs a commercial gene marker lab to identify problems, including the risk of blindness in Texels and flaws in Australian Dorpers, which provide the base for most of the NZ flock.

If breeders had access to tests that could pick up faults why wouldn’t they?, Hickford said.

Related stories: Genetic defects afflicting Angus breed explainedBreeders ignore defect advice

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