Rearing bobby lambs

October 2005
The Pendergrasts run sheep, cattle, deer and goats on a large hill country property. The lamb rearing operation began two years ago as an experiment, partly because the dry ewes from the milking flock (a totally separate business) are grazed on the property. The milking flock owner reared some replacement ewe lambs but didn't need the ram lambs apart from a few elite individuals to be kept for breeding.

Hans decided to have a go at rearing the ram lambs, did some homework and in July 2003 reared 180 which worked very well the lambs grew fast and he thought he had it sussed but they have not been able to repeat that level of success. The main problem is deaths from abomasal bloat.

There have been a lot of lambs reared by other people on calf milk powder but not with good results. However, Hans says they may be forced to try it because of cost. They have developed a system that uses less than 4 kg of powder per lamb, which is less than half that normally recommended in the industry. The lambs have access to 20% protein meal from the start. Labour costs are about the same as calf rearing so good systems are essential and you have to be prepared to put in long hours.

The biggest bugbear at the moment is losses at about two weeks of age they can get abomasal bloat, which is a gas accumulation in the abomasum and they literally explode. It is very unpleasant and happens very quickly. It is an aggressive anaerobic bacterium that lives on lactose. They still do not know what causes it to happen but there is some research being done. Hanss current theory is the large amount of meal travelling through the gut changes the chemistry of the abomasum to an environment suitable for the bacteria involved in bloat. On their mothers lambs have very small amounts (if any) of grass passing through their gut in the first 2 weeks. Yet to get the reared lambs off milk powder as quickly as possible they need to be eating meal from a young age.

He is finding that when the lambs are on once-a-day milk and the rumen is starting to function, bloat stops and growth rates rise considerably. The dilemma is how and when to introduce the meal.

Other animal health issues are:

Rolled-in eye lids easily solved by filling the eyelid with paraffin oil

Scabby mouth need to vaccinate the lambs early

Scours use dextrose and electrolytes. They use antibiotics if necessary. Their lamb Q.A. programme requires their premier lambs to have never had antibiotics in their life. They can still market lambs that have had antibiotics but they need to be tagged and then killed separately. For simplicity they are always trying to find non-antibiotic ways of dealing with problems.

Arthritis unless solved very quickly with antibiotics these lambs are not worth rearing.

Foot infections this is not scald nor footrot, but a very aggressive bacterium that invades the tissue between the cloves of the foot. Without treatment it can cause serious infection of the joints of the foot.

Clostridial bacteria on a vets advice they previously used a 10-in-1 vaccine at week 2. However, they have not seen any benefit from this programme. You cant vaccinate earlier than 2 weeks because of immune response interference caused by the antibodies the lamb receives from the colostrum. Then the vaccine takes a couple of weeks to have any value in the lamb. By this time the lamb is weaned and out on pasture. Now they dont vaccinate, but Hans is open to any evidence that it is of some value.

Selenium and cobalt the lambs are injected with a small dose of selenium and cobalt at weaning.

Worm drench the young lambs seem very susceptible to tape worms so they are drenched at weaning and every 3 to 4 weeks after that.

Probiotics as there are very limited research data on the value of probiotics it is simply a matter of trying and observing the results. As they have only 4 weeks to develop a fully functioning rumen then anything that aids that development is of value. They use Diamond XP on the meal in the shed and give the lambs biostart Ruminant at weaning. Its a bit like the vaccine situation great in theory but they dont see any obvious results.

Rearing process

The procedure is as follows:

At lambing each lamb is tagged to identify it with its mother, and left on the mother for day 1. The next day ewes and lambs are mustered, the lambs go to the lamb-rearing house and the ewes go into the milking shed. The ewes are colostrum-milked for two or three days, and once the milk is clear it goes to further processing. The colostrum is used to rear the lambs on the milking unit

Lambs come into the rearing shed on day two, perhaps 20 to 30 lambs per day, and occasionally over 100. Ella weighs them, checks their navels and puts iodine on them, does a general health check, and then late that day the new lambs are hand fed with a bottle to teach them to feed from a teat.

For the next three days they are given three milk feeds a day, and while the first couple of feeds are on the bottle, at about the third feed they are put onto the big feeder system that she has in place. Previously she fed them on the bottle for three or four days until they really settled down but there was a huge amount of work in that, so now the sooner they get out onto the big feeder the better.

So by day four they are on the long lamb feeder that has places for 15 lambs. The feeder is partitioned so that each lamb gets a set volume each feed. They are fed twice a day for 11 days, and for the next 14 days they go onto once a day. This combination of days is experimental and is still dependent on the rumen functioning well enough to use the meal that the lambs eat.

In total each lamb gets almost 4 kg of powder during their time in the shed.

At day 28 if:

1. they weigh at least 7.5 kg and

2. have grown at least 100gms/day for the last week, and

3. they have an obvious rumen

the lambs are taken completely off milk and put on 16% protein meal. At that stage they are housed in a big hay barn with ad lib access to the paddock where they can graze. They have access to meal for at least another two weeks because they take a while to settle down on grass but they do have very good growth rates once they come off powder because they are eating high-quality spring pasture, and they will be ready to kill by December.

Hans says they are really close to finding a commercial procedure for rearing lambs in this way and finishing them to killable weights. The only problems are the high cost of milk replacer, (which they can probably solve by buying cow colostrum at a reasonable price), and abomasal bloat death rate, which they dont have much of a clue on.

However, currently the economics of rearing them is quite marginal Hans can buy lambs on the store market for about the same price as he can rear them. There is little profit in doing it but it supplies the ewe replacement lambs and elite ram lambs needed for the milking flock breeding program

The milking operation has grown, and now the flock owner is milking all year round with three lambings in July, November and March. The first two are natural matings, and March one is hormonally induced. So there are lambs being born throughout the year.

The ewe flock is predominantly East Friesian, with some Polled Dorset in the background. Each flock is herd tested, and within five years the flock should be very high producing.

The lambs born on the milking platform are fed colostrum from the milking shed and have fewer problems with bloat. Lambs could be left on the mother for a few days longer, but whole lactation productivity is dependent on the amount of colostrum taken from the ewe in the first few days the more colostrum taken the greater the production for the season so it is better not to leave the lamb on the ewe but to take it away immediately and start milking the ewe completely. Even taking the lamb at day two, particularly with single lambs, probably compromises the total milk solids production for the season. It is tricky and they don't know for sure, were only going on what is known from the dairy cow industry and the way in which the individual animals production curve is established. That is the advantage of the lambs being born on the milking unit the ewes are milked but the lambs still have access to colostrum but that is not possible for the whole flock, so the compromise is that the lambs born elsewhere have colostrum for 24 hours on the mother and are then taken off. The ideal was probably having the lambs on their mothers for 4 or more days, while at the same time the ewe is milked.

Systems

There are now quite a number of farmers who are rearing 50 to 100 lambs perhaps taking one from multiple births as well as the orphans. It amounts to an additional chore for the farmer, or for his wife, at a very busy time of year. Hans says that to be successful they need to develop systems, along the lines of a modern large scale calf-rearing operations.

It wouldn't hurt to visit a calf rearing house just to get a feel for the systems they've got set up how they deal with feeding large numbers, treating sick calves, and so on, he says.

In addition there is the colostrum problem that many orphan or lost or small multiple lambs probably did not get colostrum or at most only got small amounts. This is generally not a problem for our system but is for many farmers.

The cost of lamb milk replacer is very high at 85c/litre and if you go by the recommendations on the powder bag artificial rearing of lambs is not viable. However if you are near to a dairy farm and could buy cow colostrum and /or you had some way of fortifying cows milk to make it more like sheep's milk (which has more fat and less lactose than cows milk) that could reduce the cost substantially even well below the system weve developed with minimal powder.

If people have the time, perhaps it is economic but it needs someone dedicated to it who can keep a close eye on everything. The general comment from the research that has been done is that if a lamb would die if it is not hand reared, then it is worth putting in the effort, but if it could survive on its mother, even if it was a small triplet, then it is better to leave them on the mother than trying to rear them on powder.

Management of triplet mothers has now become an art form and there are farmers who have become very skilled in triplet management and are getting fantastic results. It would be counter productive, I think, to take on hand rearing lambs and not become skilled at triplet management. The highest farm profit may well come from a combination of both.