Heifer care and management

Systems Of Production For Male Calves From The Dairy Herd

Researchers at the Animal and Grassland Research and Innovation Centre, Teagasc, Ireland, look at the different production methods for male calves from the dairy herd.

Summary

  • The main systems currently available for beef production from male dairy calves include: rosé veal (less than 12 months), 15, 19 and 22 month bull systems, and the conventional 24 month steer system.
  • Inputs and animal performance in rosé veal production systems are predictable and repeatable. Typically, carcase weights range between 200 and 220 kg.
  • Market demands dictate that young bulls are slaughtered at less than 16 months of age with a 275 kg carcase.
  • Currently the majority of bull beef is produced from the 19 and 22 month systems. While these systems do utilise pasture in the second grazing season market demands dictate that, from a meat quality perspective, an upper age limit of 15 months is suitable for young bulls.
  • Irrespective of production system, the economics of production is sensitive to calf purchase price, concentrate costs and selling price.

Introduction

With the abolition of milk quotas in 2015 and the likely expansion in the national dairy herd it is forecast that there will be a substantial increase in the supply of dairy bull calves. Developing beef production systems, in Ireland, to make greater use of these male dairy calves would make an important contribution to the economy. Finding the most suitable beef production systems for these male dairy calves is a challenge for the industry resulting in renewed interest in bull beef production as an alternative for these calves.

Before decoupling of support premia, bull beef production was generally less profitable than well managed steer beef, partly because of the higher premium earning capacity of steers. Rearing males as bulls has inherent efficiencies due to improved feed conversion efficiency and growth rate. There are many systems of beef production for male calves from the dairy herd; rosé veal (less than 12 months), 15, 19 and 22 month bull systems, and the conventional 24 month steer system. Irrespective of production system, the economics of production is dependent on calf purchase price, concentrate costs and selling price.

Under twelve month bull production system

The less than 12 month system of bull beef production is based on the production of rosé veal. Dairy bull calves are reared in conventional calf rearing units. Intakes of ration are increased to ad-libitum with straw as a source of roughage. Animals are kept indoors through to slaughter and slaughtered at less than 12 months of age. carcase weights range between 200 and 220 kg and a finishing price/kilogram of carcase weight should be agreed before the finishing period. The advantages of this system are that large numbers of bull calves can be finished once there is housing available to accommodate them. Typically, concentrate input is 1.8 t. Inputs and animal performance in ad-libitum concentrate systems are predictable and repeatable. However, this is a very intensive system and is most sensitive to changes in calf purchase price, concentrate price and sale price.

Under sixteen month bull production system

Market demands dictate that young bulls should be slaughtered at less than 16 months of age. In this system calves are turned out to pasture for the first grazing season. Animals are then housed in late October/early November and finished on good quality silage plus concentrates or ad-libitum concentrates with a limited proportion of roughage. If silage is not of optimum quality, ad-libitum concentrates should be fed. Concentrate input in ad-libitum systems is 1.8 t. Finishing animals’ ad-libitum will increase finishing costs and consequently reduce farm profit. carcase specification requires bulls in this system to achieve carcase weights greater than 270 kg.

Nineteen and twenty-two month bull production systems

Management and performance for the first season at pasture is the same as described for the under 16 month bull system. These systems are less intensive than young bull systems and facilitate good average daily gains at pasture in the second season provided pasture is of adequate quality. In these systems animals are turned out to grass for the first summer and housed in mid-November. Animals are offered ad-libitum silage plus a limited proportion of concentrates (1.5 to 2 kg/day). They are then turned out to pasture again in late February/early March. Bulls in the 19 month system are turned out to pasture for a 100 day period and are housed in late May/early June. The animals are then finished on ad-libitum concentrates for a 100 day period. These bulls are slaughtered in September/October. In this system carcase weights of 300 kg should be achieved.

Bulls in the 22 month system are turned out to pasture for a 6 month period and are housed in September. Animals are then housed and finished on ad-libitum concentrates for a 100 day period and are slaughtered in November/December. In this system carcase weights of 320 kg can be achieved. Total concentrate input in these systems is about 1.4 t/bull excluding calf rearing.

At present the 19 and 22 month bull systems are the more common systems of bull beef production. However, they are considered an unattractive product from a meat quality perspective. Older animals produce tougher meat and market demands deem an upper age limit of 15 months suitable for bulls. Research is on-going to see if this holds true.

Twenty four month steer system

The inputs and performances associated with finishing Holstein-Friesians as steers at 24 months of age have been well documented. Typically, animals spend two summers at grass and are finished in the second winter. Concentrate input is around 1 t/animal. Typical target live weights for the system are 230 kg at first housing, 300 kg at turnout in spring and 490 kg at housing at the one and a half year-old stage. Lifetime daily gain (birth to slaughter) will be around 0.8 kg/day.

Growth rate for weanlings is normally about 0.5-0.6 kg/day during their first winter and this is done to lower production costs and to optimise subsequent performance at pasture (compensatory growth). Most finishing systems are based on a final finishing period in which 120 to 140 kg of live weight gain are achieved by feeding either good quality grass silage with 4-5 kg of meal or ad-libitum concentrates plus roughage. Live weight at slaughter for Holstein-Friesian steers is 620 kg with a 320 kg carcase (kill out proportion of 515 g/kg). Typical carcasees will grade 80 per cent O’s and 20 per cent P’s and the fat scores of three’s and four’s.

Autumn born animals

Autumn born animals represent 10 per cent of the total of dairy born animals. These animals can be finished as steers at the end of the second grazing. Concentrate supplementation is about 150 kg for the first winter and calves are turned out to pasture for the first season in early spring at around 160 kg live weight. Total concentrate input at pasture is about 110 kg (for the first 6 weeks in spring and six weeks in the autumn before housing). Target average daily liveweight gains at pasture of 0.80 to 0.85 kg/day should be achieved with a target body weight of 340 kg at housing. Animals are carried over the winter on a limited proportion of concentrates (1.5 to 2 kg/day) with silage ad-libitum.

Average daily gain over the winter period is 0.6-0.7 kg/day. Animals are turned out to pasture for the second grazing season at a target body weight of 425 kg with an average daily liveweight gain of 0.85 to 0.90 kg/day to mid-August. Concentrate supplementation is introduced for the final 2 months at pasture and animals are slaughtered in mid-October. The target weights outlined in the 24 month steer system of 620 kg body weight and 320 kg carcase weight should be achieved. The potential for slaughtering autumn born calves as bulls is currently being evaluated.

Source: The dairy site
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