Friday, 23 June 2017 12:55

Breed for FE tolerance best answer

Written by  Pam Tipa
BLNZ’s genetics manager Max Tweedie. BLNZ’s genetics manager Max Tweedie.

You can treat facial eczema (FE) in various ways, but the only preventive measure is to breed for FE tolerance.

“It’s your first line of defence,” says Beef + Lamb NZ Genetics North Island extension officer Max Tweedie.

“Breeding for FE tolerance has 40% heritability so that is about as highly heritable as we can get. So much benefit is passed onto their lambs and if you choose for FE tolerance you get returns,” Tweedie told a Genetics Focus Day at Landcorp’s Kapiro Station.

By comparison, twinning rates are only 2% heritable.

Most of what occurs with FE is under the surface, so when the animals start breaking out in facial sores they are quite far gone, Tweedie says. If 5% are breaking out in the face, half your flock will have FE.

It acts on the liver which is one of the key organs for all production from growing to getting in lamb and getting back in lamb. Even sub-clinical effects can reduce productivity by up to 25%.

Tweedie says if you choose rams for FE tolerance it doesn’t compromise other traits. “You don’t lose your growth or your meat.”

However, there is no way to effectively benchmark unless you measure, which is an expensive process. The first measure used by breeders is through RamGuard, costing about $300 a head. A blood test is done to see how much of the enzyme GGT is in the blood, then a dose of the toxin is given by mouth.

Levels of GGT are measured after 21 days and this shows how much liver damage is occurring.

“Those that have less liver damage over 21 days are the ones you want to choose as parents,” Tweedie says.

The top breeders can have a rate of up to 0.6mg/kg LW; they are your top end and have a five star rating. Vice versa, at the other end those with 0.2mg/kg LW have a one star rating.

A group of top level guys call themselves ‘the FE Gold group’; they are testing at 0.6, have been testing for 10 years and are testing 10% of their sale rams.

“Ultimately we want to test as much as we can; 10% is a pretty good effort at $300 a head (for the test),” says Tweedie. It is a huge spend which will save you onfarm every year.

The other option is genomics – using DNA to see if the ram “has got the goods”.

“We do this when they are young; it is useful technology to give us more information to make better decisions to support that RamGuard tool. You can do heaps of them and get more information and the cost is about $43.

“So if your breeder is doing RamGuard and genomics, then good stuff.”

His first advice for farmer wanting to breed for FE tolerance is to choose their breeder using the flock star ratings. You can see the ratings in the RamGuard list on the Sheep Improvement Ltd (SIL) website -- from the five star rating to the one star. It will tell you how many years they have been testing and their dose rate.

“But the thing you must do is make sure you stick with them; you buy a new ram this year, you get the benefit; make sure you keep doing it.”

Look at not only their rating but how they are trending; ensure they are accelerating.

“With a good breeder, you can catch up pretty quickly as to where they are going and follow their genetic trend line as you use their rams,” says Tweedie.

But if you go with a flat-lining breeder and you are behind them you will make similar progress to them -- not much!

“You can’t just choose a high tolerance ram once; you must make sure you choose them every year. And you replace your flock with those rams to suit your breeding objectives.”

Tweedie recommends farmers use Flock Finder and other SIL web tools either on the SIL website or via an app which is easy to download on a smartphone.

“You can find where your breeders are in the ratings, whether they are recording the things you are keen on and how their rams are selling.”

He says the financial benefits of breeding for FE tolerance will depend on how heavy the FE burden is in your area and how regularly outbreaks occur, remembering that one animal with sub-clinical symptoms will have a 25% drop in production over its lifetime.

A trial in Ruakura in the 1990s ran two mobs – one FE tolerant and a control mob – on a toxic pasture with 400,000 spores. In the tolerant mob, 38% had clinical symptoms, i.e. were breaking out in the face and 23% were dead.

“This may not sound like a great result until compared to the control mob: 100% were clinical and 93% were dead.”

More like this

Farmer input needed to combat FE

Beef + Lamb New Zealand (B+LNZ) is calling on livestock farmers to take part in a survey measuring the financial impact of facial eczema (FE).

Red meat rebound

The red meat sector is poised for a strong rebound this season, with export receipts forecast to top $10 billion and farm profitability to almost double.

The future of beef breeding

Progeny testing at Pāmu’s Kepler farm in Southland as part of Beef + Lamb New Zealand’s Informing New Zealand Beef programme is showing that the benefits of hybrid vigour could have a massive impact on the future of beef breeding.

Methane targets disappoint farmers

Beef + Lamb New Zealand (B+LNZ) has reiterated calls for New Zealand to revise its methane targets after the Government's "disappointing" announcement of its revised Nationally Determined Contribution (NDC).

Featured

Farmer input needed to combat FE

Beef + Lamb New Zealand (B+LNZ) is calling on livestock farmers to take part in a survey measuring the financial impact of facial eczema (FE).

Editorial: Escaping Trump's wrath

OPINION: President Donald Trump's bizarre hard line approach to the world of what was once 'rules-based trade' has got New Zealand government officials, politicians and exporters on tenterhooks.

Wool pellets to boost gardens

With wool prices steadily declining and shearing costs on the rise, a Waikato couple began looking for a solution for wool from their 80ha farm.

National

Machinery & Products

Alpego eyes electric power harrow

Distributed by OriginAg in New Zealand, Italian manufacturer Alpego recently showed its three metre Alysium electric power harrow at the…

New seed drill tech coming

Incorporating Vaderstad's latest seed drill technology, the Proceed V 24, is said to improve precision and increase planting efficiencies for…

» Latest Print Issues Online

The Hound

Waffle man

OPINION: Prime Minister Christopher Luxon sometimes can't escape his own corporate instinct for evasion, and in what should have been…

Banks on notice

OPINION: Shane 'Matua' Jones, crusader against all things woke, including "woke banks", couldn't have scripted it better when his NZ…

» Connect with Rural News

» eNewsletter

Subscribe to our weekly newsletter