Words and images supplied by Beef + Lamb New Zealand
Dairy beef makes up the bulk of this country’s beef exports and by using the correct beef genetics, significant value can be added throughout the value chain.
The latest results from Beef + Lamb New Zealand Genetics’ Dairy Beef Progeny Test shows that up to 45kg of additional carcass weight can be achieved by mating dairy cows to the right beef bulls.
Dan Brier, General Manager of Beef + Lamb New Zealand Genetics says the latest results from the progeny test just reinforce the value of selecting the right beef genetics to use across dairy cows.
He says there is a huge pool of bulls available that can be safely used over dairy cows and offer an improvement in gestation length and calf value, hopefully reducing the number of calves that become bobbies.
“The progeny test shows we can have our cake and eat it. We can select bulls for short gestation and low birth weight, important for dairy farmers, and we can still get fast growth and superior carcass traits, important for beef finishers and processors.”
In the 2016 and 2017 seasons, 39 Hereford and 34 Angus bulls were mated via AI to crossbred dairy cows on Limestone Downs, Port Waikato. The resulting calves were run in large mobs until finishing at 23-31 months at an average of 500kg for heifers and 600kg for steers.
Bulls in the trial were selected on breeding values and the focus was on lighter than breed average birth weights, gestation length and 600-day weight.
Dan says they were conscious that while dairy farmers want short gestation, finishers want heavy carcasses, so the science team selected a range of EBVs to assess whether the numbers mirrored actual performance. This proved to be the case and EBVs were found to be good predicters of birth weight and gestation length. There were no calving problems reported.
Scientists found that while the majority of sires followed the expected pattern of heavier calves at birth growing into heavier carcasses, there were outliers that produced above average carcasses despite the calves being below average weight at birth. The inverse was also found.
“This means that while farmers can select sires to produce calves weighing 36-37kg, the final carcass can vary by more than 30kg. The key is targeting EBVs for both birthweight and 600-day weight.”
After being weaned at 90kg, the calves were run into their lifetime mobs based on weight and sex. The calves were weighed at 200, 400 and 600 days old before processing. The mean age from birth to processing was two years and four months.
Processing data showed 97 per cent of the 1017 cattle graded P2 while the remainder were L2. Again, genetics proved their worth with carcass weight, dressing-out percentage and eye muscle area all being affected by the sire.
“This means that for carcasses of the same weight, there was a variation in the weight of the high value muscles according to sires.”
A meat quality analysis carried out at Massey University found that the dairy beef meat was tender, had good colour and held its own against traditional beef.
“These results highlight the potential to increase the value of NZ’s dairy beef at every stage along the supply chain. It really is as simple as selecting the right beef genetics to use across dairy cows.”
The Dairy Beef Progeny test is on-going and B+LNZ recently announced a collaboration with LIC, this country’s largest supplier of genetics to the dairy industry.
This season, 26 bulls will be used across 1600 crossbred cows at Pamu’s Wairakei Estate. These cows are milked once-daily.
Each bull selected will be used across at least 60 dairy cows. A minimum of 45 straws will be used in the first year a bull is submitted.
Calves will be reared at Renown farm (or by a commercial calf rearer) and then transferred to Orakonui, within the Wairakei Pastoral Group, for growing out.