Replacement heifers for the suckler herd
A GOOD, efficient suckler herd is the key to productivity, disease prevention and, ultimately, farm profitability.
However, it doesn't come about by accident. Instead, careful planning and selection is essential.
Efficient Suckler Herds should:
* Rear as many calves/cow as possible ( 95% +)
* Have good quality calves at weaning time (350 kgs+ at 8 months)
* Use grass efficiently to help control production costs
* Calve all cows in a three-month period.
* Replace cows not satisfying the above criteria with in calf heifers.
The replacement strategy for sucker herds needs to bear in mind the fact that herd size in Ireland is generally small, so breeding replacements from within the herd may not be feasible. This leaves the question of whether the existing cow base has a good proportion of 'milky cows'? The farmer will also need to consider whether the cows have gone too 'pure' in terms of breeding and are therefore losing out on hybrid vigour. Many suckler replacement heifers are 3/4 bred beef crosses with some being 1st crosses from the dairy herd.
Farm facilities also have to be considered. For example have you sufficient feed and housing? The ability to acquire replacements from a reliable source is another issue as is the question of whether you afford to go out, year-on-year, and buy in replacements?
However, there are substantial benefits tof rearing replacements from within the suckler herd. This allows a farmer to:
* Focus on maintaining or even improving the potential milking ability of replacement heifers
* Select heifers from best cows in terms of their calving ability, temperament, fertility and condition
* Avoid letting the herd become too purebred. A criss-cross breeding programme with at least two breeds will maintain hybrid vigour
* Keep a closed herd which leaves stock less exposed to disease risks
* Assess the temperament of potential replacements prior to breeding
The average age of suckler heifers calving down in Ireland is just over 32 months. Heifers calving at three years of age have a lower lifetime economic efficiency compared to those calving at two years of age. Cows do not reach their mature weight until they are five years old so heifers calving at two years will obviously be smaller than those calving older but by their third calving there would be no difference. If the average age at first calving could be reduced it would make a big addition to suckler beef output.
Puberty in heifers is more related to weight than age so a good plan of nutrition is important. Traditional breeds and crossbred heifers reach puberty earlier than purebreds. Particular attention needs to be paid to the heifers at housing - she needs to be dosed for fluke, worms and lice.
Heifers are generally a very fertile group and should be bred for eight weeks. This will allow each animal two services. Heifers that are not in calf after this are less fertile and may become problem breeders in the future.
Many autumn calving suckler farmers will be using AI to get their heifers in calf. It is important to have the heifer healthy and on a good feeding programme at this time so if silage is moderate the heifer will benefit from 1 to 2 kgs of meals during the breeding season.
Heifers should be observed twice per day for 20 minutes each time to identify animals on heat. If possible they should be turned out to an area with a comfortable floor where they can interact with each other. This often stimulates the heifer to show heat.
A recently castrated steer or a teaser bull is useful in helping identify heifers on heat.