Dr Richard Spelman, chief scientist at New Zealand herd improvement cooperative Livestock Improvement Corporation (LIC), and Dr Frank Buckley, Principal Researcher at Teagasc Moorepark, recently presented to more than 60 farmers at the Newpark Hotel in Kilkenny.
The New Zealand-based geneticist visited Ireland for three days to meet with industry stakeholders across the country.
The event focussed on the science underpinning crossbreeding with high-EBI Jersey in a seasonal pasture-based system and the critical importance of calf welfare.
Science and numbers
John Tobin, systems manager at LIC Ireland, said the event offered assurance to farmers regarding crossbreeding by showing the science and numbers behind the practice.
“Dr Buckley shared Irish trial results that reveal higher productivity and higher production efficiency through crossbreeding with elite high-EBI Jersey sires” explained Tobin.
"Frank also presented two breeding scenarios based on mating a typical (average EBI) Holstein-Friesian herd to either a team of the highest EBI Holstein-Friesian sires from the ICBF Active Bull List or a team of the top EBI Jersey sires from the ICBF Active Bull List.”
“While the EBI of the resulting Jersey cross-bred heifers will be lower than that of the Holstein-Friesian sired heifers, when the contribution of hybrid vigour is factored in the profit-generating potential of the Jersey crossbred heifers is expected to be greater, by approximately €100 per cow per lactation.”
Frank pointed out that hybrid vigour is maximised in the first cross and is reduced in later generations; its expression varies depending on breeding strategy after the first cross.
He said where criss-crossing of Jersey with Holstein-Friesian takes place in alternate generations, the level of hybrid vigour expressed will be, on average, 66% of that in the first cross or approximately €100 per cow per lactation.
The gains are largely due to a combination of the complementary breed traits, giving a higher milk price of up to 6C/L, and hybrid vigour which is worth up to €150 per cow per lactation in the first cross.
He did stress, however, that as herd EBI increases and particularly where herd fertility is excellent, the advantage of crossbreeding with Jersey is lessened.
Moorepark’s 2014-2017 crossbreeding trial at Clonakilty showed that compared to high-EBI Holstein-Friesian cows with excellent fertility performance, the Jersey-Holstein-Friesian cross cows produced 9kg more milk solids yield while being 50kg lighter in body weight. The net effect was an estimated difference in profit of €138/ha in favour of the Jersey cross-bred cows.
Fertility and longevity
Dr Spelman said New Zealand research shows that the crossbred cow also has the ability to last an extra 220 days longer in the herd.
“Fertility and longevity are important for reducing environmental footprint, and crossbreeding will continue to be important to generate profitable dairy cows,” said Spelman.
Both researchers stressed that calf welfare cannot ever be compromised, and farmers need to take individual responsibility; planning ahead, making the necessary provisions for 2020 is essential.