Replacement heifers - With good management the best asset class on your farm




With good management the best asset class on your farm

Unfortunately, it is this very important asset class which often does not perform as desired, with long-term negative financial consequences. In this article we will be looking at reasons for this problem and how to address the problem as asset managers.

THE REPLACEMENT HEIFER
By definition a replacement heifer is a female animal which naturally develops in such a manner as to reach approximately 66% of her mature weight at the age of approximately 18 months, by which time she can be mated successfully and will give birth to a live calf at approximately 85% of her mature weight. She should also have a 90% chance of reconception and she has to wean at least 45% of her own body weight. She is also expected to wean a calf every year for the next 10 to 12 years with a total TKP of < 400 days. It is clear from the definition of a replacement heifer that expectations are very high and we can understand why the return (calf percentages, weaning mass and reconception percentage) is often disappointing.
THE ROLE OF GOOD MANAGEMENT
The influence of the fund manager in respect of the specific asset class cannot be over-emphasised. It includes all aspects of herd management - from supervision and health management to nutritional management and selection. We see far too often in practice that heifers are kept in a hillside camp and almost forgotten about to make them 'tough' - definitely the recipe for poor returns. The same applies when the replacement group is incorporated with the rest of the cow herd too soon. The guideline is to manage replacement heifers as replacement heifers, until they have been certified by a veterinary surgeon as being pregnant for the second time. It involves a three-year program. The potential of the heifer as future herd cow, is established here.

WHERE DOES SELECTION START? 
Selection starts during the breeding season of the mothers. Give preference to heifers born early in the breeding season: Not only do they wean at a heavier weight, but there is also a high correlation between cows which calf early and at what stage during the season their daughters will calf. Ideally 60% of cows should calf within the first three weeks of the calving season and preference should be given to the heifers. 
After weaning the selection criteria such as weaning weight (at least 10% heavier than the average weaning weight of the heifers in the group), correct build, good femininity and sexual development must be taken into account. This can be seen as the first round of selection and for this reason it is recommended that producers should make provision at this stage for the number of heifers to be selected, since some of the heifers may fall out in the second round. 

The second round of selection is when weaning takes place, after replacement heifers have calved for the first time (taking into account that they must be examined rectally by a veterinary surgeon to ensure that they reflect satisfactory sexual development). Aspects such as reconception percentage (did she conceive within the first 42 days of the mating season), weaning mass (did she wean 45% of her own mass) and growth rate (did her own mass increase after she calved) must be taken into account - all these aspects are indicators of her ability to adjust.

THE ROLE OF YOUR VETERINARY SURGEON 
The role of your veterinarian and the establishment of a focused inoculation and deworming programme, cannot be over-emphasised. Heifers have to receive their most important inoculations even before weaning. Regard inoculations as a long-term investment in your heifers and act proactively. 

Actions are often taken too late, which then makes it necessary to play fireman and put out fires. Look carefully for venereal diseases. This applies particularly in respect of producers buying in replacement heifers from time to time. Insist on veterinary certification which confirms that the animals tested negatively for current venereal diseases. 

Don't forget about the annual boosters before the mating season. It is and remains the best investment in building resistance against disease.

MANAGEMENT OF GROWTH CURVE 
A number of studies have been done regarding the growth rate of replacement heifers and consequent reproduction performance of the herd. We know that the earlier a heifer calves for the first time, the higher her productivity will be for the rest of her life. However, it is closely correlated with her feeding level, particularly during the period before her first mating season.

Tests on three different breeds indicated that the heat observation percentage of heifers growing at an average of 700g/ day, compared to heifers growing at an average of 350g/day, was almost 25% higher at 14 months. Weigh your heifers regularly and follow a strategic supplement programme in order to reach the required target weights.
Take into account that environmental and breed variations do occur and that any feeding programme has to be adjusted accordingly. This will prevent, inter alia, that animals are in an excessive condition. Also remember that heifers have to achieve their goal weight before the commencement of the mating season - emphasis once again on proactive management. 

We often find that replacement heifers, particularly in their first winter, receive the same lick as the cow group (basic winter sustenance lick), while her requirements are more in the direction of a production formulated lick (guard against energy levels being too high). This is one of the main reasons why heifers do not reach their required target weights at the beginning of the mating season. It emphasises the point of view that replacement heifers should not be incorporated with the rest of the cow group too soon. Managing them separately until after the second mating season, leaves room for better feeding managements.

CONCLUSION 
Manage your replacement heifers as the most important asset class on your farm and regard the costs relating to an effective health and feeding programme as a long-term investment in the productivity of the heifer. Do not forget the role of the bull in as far as the absence of venereal diseases, mating skills and the correct choice with regard to easy calving are concerned.

Work closely with your veterinary surgeon in establishing a health programme adjusted for your area, as well as with your animal scientist regarding a supplementary feeding programme and the management of your feed flow programme. It will ensure the development of your animals at the correct growth curves. There are no secrets or instant recipes for success. Producers who manage to replace heifers successful in their herds, are producers keeping to the basic principles, who do not look for short-cuts.