The abolition of the European milk quota system in 2015 paved the way for farms to expand production. However, the profitability associated with this extra production for individual farms needs to be examined and there must be a continuing focus on improving efficiencies, writes Karina Pierce, associate professor of dairy production, University College Dublin.
Given the significant costs associated with expansion and the fact that many farmers are operating in a scenario where land availability and building facilities are limiting the expansion of their business, a higher-output spring-calving grazing system may prove to be attractive. Such a system might facilitate the successful expansion of the farm business without the need to buy or rent extra land, buy stock, acquire extra labour or provide extra cow facilities. Furthermore, from an environmental point of view, continued increases in dairy cow numbers nationally may cause difficulty in meeting emissions targets.
The Lyons high-output herd
University College Dublin (UCD) Lyons Research Farm established a high Economic Breeding Index (EBI) herd of 60 cows in 2015 to investigate such a system, incorporating the most recent advances in grassland management for dairy farms and using a type of dairy cow that did not exist 15 or 20 years ago that has both high milk output and fertility in the genotype. The rationale is that a high-output, grass-based spring milk-production system can be profitable when built on a foundation of good grassland management and meeting both performance and fertility targets, and has a place in a sustainable Irish dairy industry. Importantly, there is little research into such a system in Ireland or internationally.
Targets of the system
The herd of 60 cows are in the top 1 per cent of EBI nationally, with an EBI of €161, a milk sub-index of €55 and a fertility sub-index of €62. The performance target is 625kg of milk solids (MS) per cow with a stocking rate on the milking platform of 3.4 live units (LU)/ha and a whole farm stocking rate of 2.4LU/ha. The performance target is 70 per cent higher than the national average figure of approximately 380kgMS per cow. Fertility targets are ambitious for a high-output herd and are the same as those used to benchmark for lower-output, high-fertility herds (75 per cent six-week in calf rate).
Feed budget 2018
From a feeding perspective, the focus is to maximise grass intake with 75 per cent of the diet coming from grazed grass and grass silage. However, achieving over 600kgMS will not happen on grass only and, therefore, cows are fed 1,500kg concentrates over the lactation to meet energy requirements. Cows are fed a flat rate with high feeding rates for the first four months post-calving and high overall intakes are achieved. Future research may compare different concentrate feeding levels or feed to yield.
Output and fertility
Output per cow is within 5 per cent of the target set at 595kgMS last year, resulting in just over 1,400kgMS per ha on the whole farm. Fertility performance, however, remains a challenge, with a lower than target six-week in-calf rate (54 per cent) and an empty rate of 15 per cent (13 weeks breeding) last year. The focus for the coming years will be to try to improve fertility performance of the herd. All areas, such as genetics, management, health and nutrition, will be considered to try to improve fertility performance.
There were 14 tonnes (t) of grass grown in 2017, 1t more than in 2016. Despite a wet spring in 2017, cows were out to grass full time on February 15 and only housed for five days during February and March. The herd utilised over 12t of grass DM per ha in 2017.
Learnings to date
From the research in Lyons over the past two years, it is evident that high levels of milk and MS output per cow and per ha are achievable in this system and, importantly, also that high levels of grass utilisation can also be achieved in higher-output grazing systems. However, the demonstration of high levels of milk production and fertility remains an issue and will continue to be our focus over the coming years of the study.