SYSTEMS OF CALF REARING
There are a number of systems which can be used to rear calves, and these are divided into Natural Systems and Artificial Systems:
|Weaning: to remove a young animal from the milk source of its mother.|
Single Suckling, used for beef calves; and
- Multiple Suckling, used for beef and dairy calves.
- Whole Milk Bucket Feeding, weaning at :
- 4 weeks
- 5 weeks
- 8 weeks
- 12 weeks and used mainly for dairy calve;
- Milk Substitute Bucket Feeding; and
- Veal Production.
This is the basic, natural system for rearing a calf, and because of this, it is by far the best system; the main problem is that it is expensive, because a cow has to be fed and maintained for a year just to produce a single calf which she rears to weaning. The cost of the system depends on the amount of feed the cow needs, to see her through the winter, in good condition.
Single suckling means that the cow calves down and rears her calf on her own milk; one cow, one calf. All the beef calves in Southern Africa are reared by the use of this method, the great advantage being that they are making use of the veld which otherwise would not be used for anything other than game. The system depends on a number of factors which are given below:
THE TYPE OF LAND AND THE STOCKING RATE
As already mentioned, beef is produced mainly from the veld which cannot be used for any other type of enterprise. The veld exists already, requires no fertilizer, and the main expense is providing water and fencing. Fencing is necessary so that the cattle can be confined to certain areas of the veld, and can be checked and collected for dipping and counting. Stocking rate is important because, by overgrazing the veld, it can be damaged beyond recovery. The golden rule when grazing veld, is to take half and leave half, so that the grasses can renew themselves for the following year. Stocking rate is the number of hectares of veld required to carry one cow, and is given as 1 to 4; this means that one cow is being carried on 4 hectares of veld. 1 To 2 means one cow per 2 hectares. The stocking rate should be related to the carrying capacity of the veld.
The carrying capacity is the number of animals that can be carried on a given area of the veld, and this will depend on the type of veld, the grasses present, the area of the country, the rainfall and other factors. It requires an expert to calculate the carrying capacity of an area of veld. The stocking rate should never be more than the carrying capacity. If the carrying capacity has been calculated as being 1 to 4, that area of veld can be stocked at 1 to 4 or 1 to 5, but never 1 to 3, because this would be overstocking and overgrazing. Overgrazing leads to loss of performance of the animals, poor calving numbers, poor milking and therefore poor calves, the death of calves through lack of nutrients, and consequently poor profits.
THE TIME OF CALVING
This is important, because it affects the feeding that the cows will require, and therefore their performance. In commercial beef herds, the normal practice is to calve the cows just before the rains start, in September and October. At that time of the year, the grass is beginning to shoot away, and young green leaves appear in the bottom of the clumps of old, dead looking grass. Once the rains start, the whole veld soon becomes green with fresh growth, and this is the best food for the cows; by then, the cows will have calved, and they will be producing milk and young spring grass is the best possible nutrient for milk production. If the cows are calved just before the rains, this means that they are dry during the winter, and need only enough feed to maintain them in good bodily condition until they calve. The time of their greatest nutrient requirement will be when they are in full milk, about 3 months after calving; by then, the veld will be in full growth, and will be able to supply these requirements in full.
Some pedigree herd farmers ensure their cows calve in early winter, or even late summer, in February and March, in order to get bigger calves for the bull sales. In this case, the cows have to be very well fed during the long, dry winter period because they are then in full milk
THE COST OF WINTERING THE COWS
This will depend on when the cows are calved down. Provided they are calved down at the beginning of the rains, they can be wintered quite cheaply, using protein licks. The veld can supply enough energy in the form of carbohydrates in the winter, but it is deficient in protein, and extra protein should be supplied to the cows. Remember that cows in late winter will be heavily pregnant, and will need sufficient nutrients to maintain their own bodily condition, and to provide for the foetus.
THE BREED OR CROSS
The breed of the cows and calves will affect their performance depending on whether or not the breed is adapted to that environment.
MILK YIELD OF THE COW
This will depend on the breed or cross used and the way in which the cow has been wintered, and the time of calving. Cross bred cows will generally milk better than pure bred beef cows. If the cow has been wintered properly, and not allowed to lose too much weight, she should be in good condition when she calves down, and should milk well. If she has been badly wintered and is in poor condition when she calves down, she will have to make up that condition from the fresh grass. This means that she will not milk well until she has replaced her reserves of fat, and the calf will suffer because of lack of milk. Cows that calve down after the rains have started will be in good condition because they will have had plenty of grass before they calved; however, they will dry off when the grass loses its quality in the autumn and before the late born calf has gained the full benefit of the milk. A poor cow might give 700 litres only, during her lactation, and this will give a poor calf. If the birth-mass of the calf is known, and the 205 day mass, the daily live-mass gain of the calf can be calculated using the following formula:
205 day mass – birth mass = Average Daily Gain (A.D.G.)
The 205 days is a standard which is used to compare the performances of calves with each other. 205 Days is almost 7 months, and this is the time at which most calves are weaned from their dams.
For example, a calf weighed 35kg at birth, and 210kg at 205 days; its Average Daily Gain would be:
210 – 35 = 0.85kg per day
Suppose a second calf weighed 35kg at birth, and 175kg at 205 days, its A.D.G. would be:
175 – 35 = 0.68kg per day
CREEP FEEDING OF CALVES
|Creep feed: solid feed given to young animals in order to wean them.|
Some farmers, and particularly pedigree breeders, who want to improve the A.D.G. of their calves, will give them a creepfeed while they are still suckling their dams. This is done by putting some meal in a trough, which is fenced off from the cows, but allows the calves to get in and feed. It is usually a square area in the veld which is fenced off with wooden poles which the calves can get under, but which the cows cannot. This is quite an expensive operation because the calves will eat meal from one month old. They start by getting 0.5kg of meal a day, and this can be increased gradually to 2kg a day. It does mean that the calves grow much faster and look in better condition, but it is expensive and not many commercial farmers provide creep feed for calves; and
Under the single suckling system, losses of cows and calves should be very small, provided the animals are given a sound vaccination programme against the common diseases in the area. Most calf losses occur at calving, and most of these can be avoided by good supervision over the calving period. Cows should live for 8 – 9 years, and provided they are properly fed, they should produce a calf each year.
As we said at the beginning of the lecture, the Single Suckling system is by far the best method of rearing calves, because it is a natural method. The benefits of the system can be summed up as follows:
- The calf gets the colostrum from its own mother, and this is most important in giving immunity from certain diseases for the first two weeks of its life.
- The calf gets the milk in small quantities and at frequent intervals – little and often is the best way of feeding milk to all young animals, because they cannot handle large quantities of milk when they are young, as they have small stomachs.
- The calf gets the milk at the right angle; the teats of the cow are at the right height for the calf, i.e. at the level of its head. When it is drinking, the calf’s head and neck are stretched out in a straight line, so that the milk goes down the right tube, the oesophagus, and not into the trachea which leads into the lungs. One of the greatest difficulties of teaching a calf to drink milk out of a bucket is to overcome its natural inclination to put its head up to drink.
- The calf gets the milk at the right temperature, and again, this is most important. Half the trouble in artificial rearing is feeding milk that is either too hot or too cold.
- The milk is fresh and uncontaminated when drunk by the calf.
Young calves are weighed on a cattle scale or placed in a bag and weighed with a spring balance.
 The Birth-mass of the calf is a measure of the way the cow has been fed before calving, and it is also affected by the breed or cross of the calf. The 205 day mass, and the Average Daily Gain of the calf is a measure of the milking capacity of the cow, because, for the first few months of the calf’s life, it depends on the milk it receives from its dam. A good milker will produce a calf with a good A.D.G. and a poor milker will produce a calf with a poor A.D.G. An A.D.G. of 0.8 – 0.9kg is good, and 0.5kg is poor. Cows that usually produce a calf with a poor 205 day weight and a poor A.D.G. should be culled from the herd because they are poor milkers. It is often the cows that are fat and in good condition at weaning who are the poor milkers, not the cows that are rather thin and poor looking.
In this system a cow rears more than one calf. It is normally used to rear dairy calves, and cull cows from the dairy herd, are used as the mothers. They are better milkers than pure beef breeds, and the cow has more milk than one calf could drink anyway.
Cows that are used for multiple suckling are often cows that are chronic mastitis cases, poor butterfat cows, cows that have only three teats, slow milkers, etc. The most important thing is the temperament of the cow, because she is going to have calves taken away from her, and fresh calves given to her. A cow that is bad tempered, will not accept the fresh calves and is no use for this system. A quiet docile cow is the ideal animal.
Calves should be left on their own mothers for at least 4 days, so that they get the correct colostrum, and preferably for about a week, so that they are fairly strong before they are moved. They should be starved for 12 hours, and then introduced to the multiple suckling cow in a pen; the cow should be given feed of meal while the calves are drinking as this tends to keep her occupied while the calves have their first feed. A heavy milking Friesland cow, one giving 20kg or more a day can take 4 calves at once, and rear them well. Such a cow would require feeding some meal, and this can be done while the calves are suckling for the first few days. After that, once the cow has accepted the calves, she can be turned out into a paddock with them, so that they can drink when they require. The calves should all be about the same size, otherwise the largest calf will take most of the milk, and the others will suffer.
Under this system, the calves would be weaned, i.e. taken away from the cow at 12 weeks old, and another lot of calves would be given to the cow to rear. A good milker will rear 4 calves for the first 12 weeks of her lactation, then 3 calves for the next 12 weeks, then 2 calves and finally 1 calf, making a total of 10 calves. Provided she is on good grazing, by the time she has 3 calves she will not require any supplementary feeding. It is obvious that a poor milker will not be able to rear as many calves, and the farmer must use his judgement about how many calves he gives to a cow.
Since the calves are being weaned off milk and away from the cow at 12 weeks old, as opposed to the 7 months weaning of the single suckling system, it is necessary to get the calves to eat solid food before they are weaned. Some hay and a concentrate meal should be put out in a trough in an area of the paddock which has been railed off, so that only the calves have access to the trough, otherwise the cow will eat all the hay and meal. The diagram below will give you some idea of a creep feed. The hay and concentrate should be made available for the calves when they are about 3 – 4 weeks old, and the meal should be given to them ad lib (i.e. not rationed, but a small amount put in the trough which they can eat as often as they require). The trough should be cleaned and fresh meal given each day. By the time the calf is weaned at 12 weeks, it should be eating 1kg of hay and 2kg of concentrates each day, and provided it is eating approximately this amount, and the meal and hay are fed to it after weaning, the calf should carry on growing quite nicely. When they have been weaned, the calves will have to be shut in a pen for a few days, until they have got used to the idea of being away from the cow. After weaning, the hay and meal should be increased gradually until, at 24 weeks, the calf is getting 5kg of hay and 2kg of concentrate a day. The concentrate is kept at 2kg as this is enough for the calf, and silage can be fed instead of hay.
Figure 1: A Type of Creep Feeder for Calves