Improving nutrition a few weeks before calving is successfully boosting health outcomes for calves and heifers in the trying weather conditions of Australia’s north.
The Calf Alive project led by The University of Queensland and funded by Meat and Livestock Australia is trialling ways to overcome the impacts of poor diet and heat stress on beef properties in North Queensland and the Northern Territory.
Project lead associate professor Luis Prada e Silva says the results are extremely promising.
“For two years now, we’ve been improving nutrition in the last four to six weeks before calving and we are seeing very clear benefits on the milk delivery to the calves.
“At weaning, both the supplemented cows and calves are heavier, resulting in an extra 19 kg of weight production per lactating cow,” Dr Prada e Silva said.
Calf loss in beef breeding herds is a problem globally and a significant productivity challenge for the Australian beef cattle industry.
Low fertility is another issue, with first-lactation heifers struggling to maintain decent milk production and return to fertility.
“We are seeing a significant increase in the conception rate of these first-calf heifers.
“Without good nutrition, it’s not easy for a cow to become pregnant again shortly after calving,” he says.
“We’ve found extra nutrition in those last critical weeks is boosting pregnancy rates in the four months after calving from 50 to 65 per cent.”
Extra nutrition is resulting in a heavier calf at weaning and a cow that has better body reserves to become pregnant again the next year – so it’s a carry-over effect.
“It gives producers the benefit of better production this year and even better production next year.”
Dr Prada e Silva said producers were excited by the possibilities of the research, but the team still had more goals to achieve.
“We want to be able to quantify the impact of improving the nutrition of pregnant cows so producers can make their own decisions on whether it’s worthwhile, and the best way to make it happen,” he said.
“A second outcome would be an index for heat stress in northern beef systems.
“We're using sensors to evaluate how animals respond to heat stress, the impact on calf survival and the overall productivity of herds.
"By monitoring how cattle behaviour changes in response to climate events and the impact on production, we can determine the appropriate heat stress index associated with loss of production.
"We are also testing a new tail hair test for early identification of cows with better reproductive efficiency and higher liveweight production.
"One goal of the project is the verify if nitrogen isotopes in the tail hair can be used to predict future performance of cows.
"Early identification of more productive cows can have a significant impact on the industry.
"We're excited to see where the Calf Alive project takes us and can't wait to share more good news soon.”
