Central to achieving 24 month old calving at 540-580kg live weight and the resultant economic benefits is a controlled feeding and management approach throughout the rearing period from 12 weeks old to the point of calving.

John Thompson and Sons Ltd. in collaboration with AFBI and CAFRE, have developed a series of rearing blueprints to achieve a liveweight gain of 0.7-0.8 kg/day from 12 weeks old to calving.

The blueprints take into account different management and feeding policies, land availability/accessibility, labour resources and in particular the season of birth of the calf, as this has a significant impact on the ease with which targets will be met on farm. This is particularly important with March-July born calves.

Three of the blueprints are based on winter diets using grass silage with an ME content of approximately 10.7 MJ/kg DM and summer grazing. The fourth is based around a housed system using straw as the forage. In each case a concentrate allowance of an appropriately balanced Heifer Rearing concentrate is recommended to enable target growth rates to be acheived.

Rearing the August-November born calf:- Key Points

12 Weeks old – mid April

• Achieve steady growth rate over the period - balanced nutrition required throughout

• Good ventilation and no draughts in the rearing house

• Good calf health requires good nutritional and housing management

From Mid April – Autumn

• Maintain a level pattern of concentrate supplementation at grass to ensure adequate calf growth

• Adopt management and veterinary routines to control parasites

• House sufficiently early in Autumn to ensure performance is maintained

Breeding Management

• Minimise stress around mating and maintain a steady nutritional regime before and throughout the breeding period

Post-Breeding and Pre-calving

• Maintain steady growth rate throughout pregnancy and calve down at Condition Score 2.5-3.0

• Acclimatise heifers to the post-calving diet for 3 weeks pre-calving

Feed Plan to Achieve targets with August – November born calves

Rearing the December-February born calf:- Key points

12 Weeks old – 9 months of age

• Calves should be kept inside until at least 12 weeks of age

• Pasture quality must then be very good, and good parasite control adopted

• Concentrate may be required throughout the summer to ensure controlled growth rates – this is primarily a factor of grazing management

• House in early Autumn to ensure a steady growth rate through this difficult period

Second winter

• Settle animals quickly onto full winter rations and adopt an appropriate parasite control programme

Second summer

• These animals must be kept growing at pasture and this may require supplementation with concentrates, depending on grazing management

• House in early Autumn to ensure animals maintain steady growth during pregnancy

Pre-calving management

• Maintain a steady growth rate throughout pregnancy and calve down at Condition Score 2.5 - 3.0

• Acclimatise heifers to the post-calving diet for 3 weeks pre-calving

Feed Plan to Achieve targets with December – February born calves

Rearing the March - July born calves:- Key Points

12 Weeks old – 11 months of age

• One option is to keep these calves inside until 11 months of age and preferably offered straw as the basal forage

• While this method adds costs it is essential if these calves are to calve down at 24 months of age

• This method also allows for pulling these calves towards 22-23 month old calving which may be beneficial in terms of herd calving pattern

Second Summer period

• These animals must be kept growing at pasture and depending on grass quality and grazing management supplementation with concentrates may be required

• At grass a good parasite control policy is vital

• House in early Autumn to ensure animals maintain steady growth during pregnancy

Pre-calving management

• Maintain a steady growth rate throughout pregnancy and calve down at Condition Score 2.5 – 3.0

• Acclimatise heifers to the post-calving diet for 3 weeks pre-calving

Feed Plan to Achieve targets with March - July born calves

Straw System:- Key Points

• Conventional grass silage and grazing systems have their advantages e.g. reduced variable costs. However in some farm situations e.g. shortage of land/labour or requirement to reduce bio-security risk with off-farm grazing, straw-based systems may offer an advantage

• Straw must be of good quality

• Allow animals access to grazing during some stage of the rearing programme to enable them to develop grazing skills

• Remember animals put to grazing after being housed for most of the rearing period are still susceptible to intestinal parasites despite their age

Feed Plan to Achieve Targets with a Straw-based System

Summary

Key issue is steady growth rate of 0.7-0.8 kg/day from 12 weeks old to calving at 540-580 kg, condition score 2.5-3.0