Tasmanian dairyfarmers Trevor and Tanya Saunders believe they get the ‘best of both worlds’ by using a combination of progeny test (PT) and proven bulls over their herd: the PT bulls offer potentially superior genetics at a reasonable price, while the proven bulls offer more reliable information to use in the selection process.

The Saunders dairy at Scottsdale in north east Tasmania, milking 230 cows with calving split equally between autumn and spring.

Mr Saunders has used a combination of progeny test and proven bulls for more than 20 years. And while he is pleased with the results, his main motivation to use PT bulls is to enable the industry to evaluate the next generation of proven bulls.

“It is really important to have accurate information about the performance of bull’s daughters under Australian conditions. That’s what the Australian Profit Ranking and Australian Breeding Values are. But the whole system relies on farmers using PT straws and herd recording. We can contribute to that and get good results in our herd at the same time,” said Mr Saunders.

Progeny test straws are used over 25-40% of the Saunders’ herd, depending on milk price which determines the breeding budget.

“PT bulls are very good value for money plus we get the latest genetics. The downside is they haven’t any daughters milking so information is limited. In theory there’s a chance some won’t live up to expectation but we’ve been very happy with the all of the cows we’ve bred from progeny test bulls,” said Mr Saunders.

For example, the Saunders’ used progeny test straws from Farm Dealer who is currently number five on the Australian Profit Ranking list and Carlos who is currently number four.

“We are delighted with the daughters from Farm Dealer and Carlos. Using them as progeny test bulls means we had their daughters in the milking herd several years earlier than people who waited for them to be proven. So we’ve fast-tracked genetic gain.”

Mr Saunders recognises that proven bulls have the benefit of coming with a lot of accurate information.

“When milk price is high, we tend to use more proven bulls, but we always use at least 25% progeny test bulls.”

A key to the Saunders’ success is using a team of 8-10 bulls which provide plenty of choice to avoid inbreeding and helps spread any risk associated with reliability.

Each season Mr Saunders chooses about five progeny test and about five proven bulls to use over the herd.

“Our long term breeding objective is to improve milk protein production while keeping workability above average.”

He tends to look mostly at pedigree when choosing progeny test bulls while proven bulls are selected on the basis of Australian Breeding Values (ABVs).

“I’ll often choose a progeny test bull who is the son of a really good proven bull. And I go for proven bulls with ABVs that are superior for the key production traits and workability,” he said.

To avoid inbreeding, Mr Saunders uses an inbreeding report screening service to match specific bulls to individual cows.

“The screening report takes the hard work out of avoiding in-breeding and also allows us to go back and re-use bulls that have performed really well over our herd.”

Overall, the Saunders are confident they are making progress towards their breeding objective.

Milk protein percent and type are improving every year.

“The improvement in protein is due to a combination of improved genetics and nutrition. The beauty about improving genetics is that it’s permanent and we get the benefits year after year,” he said.