By Teagasc Green Acres Programme advisor James Fitzgerald

As the autumn 2020 calf crop are now hitting the ground, the participants of the Teagasc Green Acres Calf to Beef Programme – who operate autumn-calf systems – are undergoing their yearly task of sourcing, purchasing and rearing autumn calves.

One such farmer is Aidan Maguire from Navan, Co. Meath, who is tweaking the way in which he sources his autumn calves in the hope of improving returns and reducing time input on his farm.

Aidan rears 120 Friesian, Angus and Hereford calves each year, in a 90 spring-born and 30 autumn-born split. He is aiming to bring all of these cattle through to slaughter between the ages of 20 and 24 months.

In the past, the autumn-born caves were purchased at calf marts and through cattle agents with varying success. This year, Aidan is putting an increased focus on herd health and the genetic makeup of the calves as he sources them to improve his farm profits down the line.

Reducing the number of sources

Having had trouble with calf health in previous autumn-born batches, Aidan has focused on reducing the number of different herds his autumn calves are coming from.

The reason for this is that the more different herds that calves are bought in from and mixed with, the higher the chance of buying in an unwanted herd health problem.

This year Aidan has 15 Angus autumn calves on the farm which he purchased off of one local dairy farmer and he is in talks with another local dairy farmer about buying 15 dairy-bred bull calves.

This is a huge change on the year previous, when the 30 autumn calves reared on farm had originated from 12 different herds. The reduction in different sources should help greatly in reducing the risk of a disease outbreak during the rearing stage.

In addition, being able to transport the calves directly from the dairy farm and getting them settled into their rearing area on Aidan’s farm – should also reduce the risk of respiratory problems over the rearing stages.

Calf Genetics

Understanding the genetic potential of the calves is extremely important in making the right decision on whether or not to purchase, and at what price.

Last year’s autumn calves purchased by Aidan were all dairy-bred male calves and nothing was known about their genetics prior to purchase. Now having the ability to look at the Irish Cattle Breeding Federation (ICBF) data, we have found that the average carcass weight figure for the 2019 autumn calves is -1.7kg.

This year Aidan is sourcing calves with positive figures for carcass merit. He has done so through gaining all the information he can about the genetics of both the dams and sires, of which the calves are out of.

Aidan Maguire

Having visited the farm and seen the cows, Aidan was happy with their size and shape, and knew that their genetics wouldn’t hamper his calves’ ability to meet the carcass specs required.

He was also given access to the ICBF indices of the Aberdeen Angus bull used to sire all of the autumn calves on the farm. This bull is a stockbull with a carcass weight index of +8.2kg and a carcass conformation index of +0.51.

These positive figures for carcass traits will help to increase the slaughter performance and potential income Aidan can generate for his farm.

Rearing and health management

The 15 calves already bought were collected off the dairy farm once the youngest calf was three weeks old. This gave Aidan a good start with strong calves which he vaccinated for pneumonia and IBR once they were settled.

The calves were fed 600g of milk replacer split into a morning and evening feed and given access to concentrates ad-lib. A deep bed of dry straw and clean water were kept with the calves at all time.

These calves were weighed on October 30 and weighed an average of 106kg – having an average daily gain (ADG) of 0.72kg from birth to now.

These calves are now being weaned off milk as they are well ahead of the target weaning weight of 95kg and are consuming over 1kg of concentrates/day.

Long-term plan

Looking more long term, the plan is to kill off the autumn-born stock off grass at two years old, following a 60-day finishing period.

The aim is for the Aberdeen Angus and Holstein Friesian steers to return an average carcass weight of 320kg at O=grading. The target for the Aberdeen Angus heifers is to return a 280kg carcass at an average grade of O+/O=.