The fertility issue within the national dairy herd seems soon to be resolved and it is time for farmers to focus on breeding for health, according to Siobhan Ring from the Irish Cattle Breeding Federation (ICBF).
Ring was speaking at the European Holstein and Red Holstein Conference, hosted by the Irish Holstein Friesian Association (IHFA) in Dublin.
Ring outlined that great improvements have been made in fertility and production traits since the introduction of the economic breeding index (EBI), with an additional €200 profit/cow/lactation since its introduction.
But if we look at health, we are still seeing improvement, but not to the same extent as fertility and milk. Ring said that if the cow is not healthy, all her potential is absolutely wasted.
Health
Ring explained that by 2031, based on current trends, the fertility issue within the national dairy herd should be solved, with cows calving every 365 days.
She then posed the question that if we can breed for better fertility and production within our cows, can we also breed for better health?
According to the Ring the answer is yes, but the gains will be much slower and more health data is required on sires and their progeny.
Ring said many farmers see disease as the flip of a coin, with a 50:50 chance that the animal will be healthy or not, but she added that genetics disproves this, and some bulls have a better tolerance for diseases.
Using somatic cell count (SCC) as an example and using two different groups of bulls, Ring showed that only 10% of one group of bull’s progeny had high cell counts, whereas from the other group, 50% of the progeny had high cell counts.
“As a farmer I know that I do not want to be picking the bull from the high cell count group and I want to aggressively select a bull from the low group – which have few incidents of high SCC.”
Improvement
Ring posed the question as to why we are not seeing the same gains in health as we are in fertility.
She responded by stating that there are a couple of things we need if we are to breed for improved health – firstly there is the need for genetic variation.
The other area is selection intensity, within the EBI, health accounts for 8% – whereas production and fertility have a higher weighting and get more focus from farmers.
“Farmers need to be selecting aggressively on higher health bulls, if they want to improve health at a faster rate,” Ring said.
The other areas that require focus according to Ring is how precisely the health data is being recorded and that is influenced by the amount of data sent to ICBF.
Health traits are lowly heritable, which means that a lot more data is required, compared to milk traits to achieve high rate of progress. Just because we need a large amount of data, does not mean that we cannot make genetic gains according to Ring.
The ICBF representative also explained some analysis conducted by ICBF, where two groups of animals were compared. One group was said to be good for health traits versus the other group of animals that were not.
The analysis determined that the animals which were said to be of good genetic merit for health, did end up having lower incidents of health issues throughout their lifetime.
For tuberculosis (TB), there was a 26% reduction in incidents, between the poor and good genetic animals, while for mastitis there was a 58% reduction.
Even with low reliability, Ring said that improvements can be made if farmers want to and they select correctly.
Concluding her presentation, Ring said that she believes that fertility “is solved” within the national dairy herd.
That having a healthy animal is an necessity, that it is not a nice to have and that health is under genetic control, but gains will be limited without adequate data.