Researchers at UCD Lyons Estate are halfway through the six-year project looking at high-output, spring-calving, grass-based dairy systems. The project started in 2016 and will run until 2021.

There are 60 high-EBI Holstein Friesian cows in the study. The stocking rate is 3.4 cows/ha on the milking block (2.4 cows/ha overall) and the aim is to feed 1,500kg of meal per cow and produce 625kg of milk solids per cow.

The EBI of the herd was €161 in 2018, putting it in the top 1% of herds nationally. The EBI sub-index for milk was €56 while the sub-index for fertility was €61. The PTA for milk, at 78kg, was in the top 40% nationally. The EBI for 2019 is €179, which again is in the top 1% nationally.

Actual performance

The mean calving date in 2018 was 15 February. Cows are on a pre-determined diet based on their days in milk. They start off on 8kg of meal for the first two months of calving. This is reduced to 6kg for months two to four and they are on between 3kg and 4kg of meal for the rest of their lactation. During the drought in 2018, cows were fed a maize and grass silage partial total mixed ration (TMR) for five weeks. Total meal fed in 2018 was 1.76t/cow.

Cows get 60 days dry, but are dried off earlier if they are milking less than 9l of milk per day. In 2016 and 2017, all cows were given teat sealant and selective dry cow therapy but after observing an increase in SCC in 2018, all cows were given an antibiotic dry cow tube at the end of the 2018 lactation.

Actual milk yield and milk solids produced by the herd was approximately 5% below target in 2016 and 2017. In 2018, actual milk yield and milk solids produced was approximately 13% below the target at 544kgMS/cow and 6,790kg/cow. Milk yield and composition data are presented in Table 1.

Breeding

Body condition score (BCS) is assessed fortnightly. Average BCS was 3.02 in 2018. The breeding season started on 29 April 2018 and lasted for 12 weeks. A pre-breeding scan was carried out prior to the breeding season to identify and treat any problem cows. AI was carried out twice daily in 2018 and heat detection was carried out using Moomonitors, crayons and scratch cards.

Fertility performance of the herd is presented in Table 2.

Submission rate, conception rate and pregnancy rate are based on the number of cows bred. Empty rate is based on all cows in the herd, including those not bred.

Financial performance for the farm was back considerably in 2018 compared with 2017.

The net margin per cow fell by €674 to €579 in 2018.

Researcher Karina Pierce explained that this is due to a number of factors, such as “the extra concentrates, forages and associated contracting costs to feed the cows during the snow storm in February/March and the drought during the summer”. She said: “There was also lower milk production in 2018 compared with previous years due to a higher proportion of heifers in the herd (28% heifers), weather events and a lungworm problem that occurred in the summer.”