Setting the sights on milking quality silage in Co. Mayo
Donal Ronayne is in his third year of milk production, milking a herd of 194 spring-calving cows in south Mayo.
A participant in the Teagasc/Aurivo Joint Programme, he joined Teagasc Dairy Specialist James Dunne on a recent Let’s Talk Dairy webinar to discuss the performance of the farm this spring, his plan for silage and this year’s breeding programme.
After completing a degree in Agricultural Science in UCD and gaining experience on a number of grass-based dairy farms in the west, Donal entered a collaborative arrangement with his uncle. 2021 was the first year in which cows were cupped on the Mayo-based farm, having previously been a suckler farm.
Consisting of a total of 90ha (adj.), the milking platform stands at 53ha and carries 3.7LU/ha. With 24ha dedicated to silage production and 13ha of a heifer rearing block, the overall stocking rate is 2.7LU/ha. From a concentrate input of 1t/cow, 500kg of milk solids per cow were produced in 2022. This is an impressive level of performance given that the majority of cows milked were only in their second lactation. Over the coming years, Donal hopes to improve this production further, with the aim of producing 530-540kg of milk solids per cow at a cow liveweight of ~550kg.
Spring grass
Donal touched on the grassland performance of his farm this spring, noting that it was very much a “tale of two halves”. With a very compact calving pattern, having 80% of the cows calved in the first four weeks, grazing days up to March 10th were maximised.
“Obviously grazing conditions were so good we were full-time grazing from the get go. We had nearly 50% grazed by the 6-7th of March. We were gone ahead of target, but I kind of knew there was more than likely going to be a spell of weather where we would struggle to get out. At that point, the weather did change and we were forced to stop grazing for periods rather than choosing to stop.”
During this time, on-off grazing was employed, with cows given access to grass for three-hour blocks in the morning and evening. However, on some days when weather conditions didn’t permit grazing, cows remained indoors.
“Basically, we tried our best to get grass into them at least once a day if we could and anytime we saw a break in the weather to go at it a bit harder again, we did,” Donal explained.
Donal is targeting pre-grazing covers of 1,400kg DM/ha, but a dip in growth rates in late April resulted in farm cover slipping to ~500kg DM/ha. In a bid to extend the grazing rotation, the quantity of concentrate offered to cows was upped to 6kg/head/day to tide him over until growth rates recovered sufficiently to meet demand.
Silage production
Although the spring has been challenging, Donal’s focus on producing quality silage, capable of supporting milk production during the shoulders of the year, has not wavered.
As the farm is quite heavy, with the grazing season typically ending in the first week of November, and a high stocking rate is operated, cows are generally milked out of the shed for six weeks in the late autumn. With this comes the requirement for having high-quality silage stocks available. A reserve of silage is also targeted, with the aim of having 1-2 bales equivalent of high-quality silage available to buffer feed cows through difficult weather conditions such as those experienced this spring.
On April 22th, silage paddocks on Donal’s farm had a cover of ~3,000kg DM/ha. On silage harvesting this year, Donal commented: “If weather conditions allow, cutting will be completed around the 15th of May. The three cuts the last two years have tested in and around 74 up to 77 [Dry Matter Digestibility]. The first cut usually tests around 76-77.”
“If we get the weather at the cutting time it will be milking quality silage.”
When asked was he tempted to push out cutting date to the end of May to achieve a heavier bulk to help build silage stocks, Donal responded: “No, when you do that you’re definitely going to lose it at the other end in the second and third cut. Our third cut is in by the middle of August. You get a spell of weather at some stage and you get three good quality cuts, whereas if you push out the first cut to the end of May, you are probably going into September for the third cut and often September silage is poor dry cow feed.
“We have no issue with silage quantity. The stocking rate is very high overall and we still have surplus silage every year. This year again we have enough of silage in reserve for a two month winter as we are.
“We don’t have any issue, we’re getting 17-18t DM grass off ground in three cuts so and I don’t see it as an issue here,” he said.
Watch the recording of the webinar below where Donal also discusses his plan for breeding this spring:
Let's Talk Dairy is a weekly webinar series held every Thursday morning, offering timely, relevant and practical advice to allow you make better management decisions on your dairy farm. Watch back previous webinars or register for future webinars here.
This webinar is also available in podcast format below:
Also read: Managing late-calving cows to shorten calving interval