Why lax calving patterns cost the average dairy farmer thousands

A spread out or lax calving pattern costs the average 100 cow dairy herd €27,000 a year, Teagasc’s Brendan Horan has said.

Speaking at the Positive Farmers Conference in Co. Cork, the Teagasc Research Officer said this is due to lost productivity through reduced grass utilisation and milk production combined with increased infertility.

Horan added that calving compactness on Irish dairy farms is far below target levels, with the average six-week calving rate on Irish dairy farms being 58% in 2016.

For efficient grass-based systems, he said, the target six-week calving rate is 90%.

This target is directly linked with farm profitability and research carried out by Teagasc shows that reduced calving compactness costs €8.50/cow for each 1% drop below the 90% target.

And as a result, he said that increasing the six-week calving rate should be one the main targets Irish dairy farmers have when trying to improve production from grazed grass.

When should farmers calve their cows?

The Teagasc Research Officer also discussed optimum calving date, and he said the the optimum date will be the earliest date which will allow the entire herd to be turned out to a predominately grass-based diet immediately after calving.

Many dairy farmers have chosen to delay calving because of higher stocking rates and more compact calving patterns on farms in recent years.

“While this will shorten the interval to magic day and consequently reduce the requirement for supplementation of pasture in spring, it will also shorten lactation length and require increased supplementation during the autumn,” he said.

Horan also said that the overall optimum calving date will be chiefly influenced by both farm soil type and spring growth capability.

This will range from February 10 to March 1 depending on specific characteristics of the farm.

“Ultimately, the ideal herd mean calving date for any individual farm will be the earliest date when a farm stocked at the correct overall farm stocking rate can be calved to facilitate a 280+ day herd mean lactation length and allowing for 90% of the herds feed requirements to be achieved from pasture,” he said.