Wednesday, 17 March 2010

Twin Lamb Disease

Not a disease as such at all, the posh name being Pregnancy Toxeamia. Often linked with ewes carrying multiple births, but not always the case.

As ewes get heavier in lamb the lambs inside them ask more of their mothers. The lambs are growing and require more sustenance from their mothers, the ewes then use more of their built up reserves and this is when the problem may arise.

The reserves that the ewe has built up in her body are stored as fat or take the form of sugar and glycogen throughout the liver and muscles of the body. If she uses up the sugar reserves this will cause her blood sugar levels to drop, she will then call upon her fat reserves in an attempt to raise the blood sugar levels, unfortunately as the fats are broken down by the liver ketones are formed. Excessive ketones end up poisoning the system eventually producing an effect similar to alcohol abuse in humans.

Well managed feeding of the sheep ought to help keep twin lamb disease at bay, however, there are always the odd ones which may well succumb. The ewe just needs to have an 'off' day, not eat as well as usual, and the body will automatically begin to draw upon its own reserves and try to make up the deficit. Almost any form of stress, be it the weather, a day through the sheep pens or even a change in feed could well be enough to trigger twin lamb disease in a ewe.

I have always found two symptoms which draw me direct to the conclusion of twin lamb disease. Blindness and sweet breath.

The blindness does not affect the appearance of the eye (unlike snow blindness)but you'll find if you wave your hand past the eye or move your finger towards the eye there will be no reaction shown, the ewe ought to at least blink - but she wont.

As for the breath - it has a definite sweet odour about it which I believe arises from the ketosis. The next time you see a shepherd seeming to wave at a sheep then smell it's breath they haven't lost their marbles, they are diagnosing.

The sheep I had the pleasure of finding 'off' the other morning were showing some of these signs, fortunately for them they were still mobile and with the rest of the flock, however a built in sense of 'something not right' came to the fore.

The early signs may have a ewe lying off from the flock, or not coming in to the cake. These particular sheep were on ad lib blocks, it is always possible that some ewes were not eating the blocks or maybes were getting pushed out by greedier sheep. One ewe was lying behind the wall, looking as though she was sheltering and did rise and join the rest of the flock with encouragement but there was no doubt about it that something was wrong. The other was still with the main flock but something about her demeanour made alarm bells ring in my head. Interestingly enough we had had a hard frost the previous morning followed by a strong cold relentless wind all day - could it be possible this was sufficient stress to cause these ewes to call upon their own bodily reserves? Who knows.

In both cases the ewes appeared to be blind and one most definitely had a sweetness about its breath. A home made glucose drench was administered with an injection of calcium and magnesium also given. Calcium and magnesium deficiencies cause lambing sickness and staggers, a poorly sheep can easily succumb to this and it never does any harm to cover the possibilities.

Unfortunately it is difficult to pull a ewe back from full blown twin lamb disease. The success rate is only a few percent. She will be off her feet, off her food and reliant on you to keep her re hydrated and trying to raise her sugar levels whilst the poison of the ketones gets to work on the rest of her body. The best chance of survival is to get rid of the cause - that being the lambs inside her.

Now women can suffer from the same problem. They will find themselves in hospital, closely monitored, drip fed to keep glucose levels up. Once the condition of the expectant mother is stabilised she will probably be given a ceasarian section with the premature baby heading for an incubator in the special baby unit. A hugely worrying and dangerous time for all involved.

The ewe is less fortunate. It is often hoped that they will keb (abort), the ewes last resort to saving her life, one which may happen naturally or injections from the vet can be administered, however, these don't always work. Which ever scenario it is highly unlikely the lambs will survive unless they are close to being full term. As for a ceasarian? Yes it is an option available but one which is rarely considered. Should the lambs inside her already be dead (which is highly probable if she has been sick for a while) the chance of subsequent infection and death of the ewe is high. A great risk when the cost of a ceasarian will be well above the value of a normal hill sheep. Unfortunately there is not a national health service for sheep which means weighing up the pros and cons before heading for major surgery on an animal valued at less than the cost of the treatment, especially if the outcome has a high probability of being unsuccessful.

Should the ewe not be able to be rid of her lambs life looks bleak for her indeed and after a duration it is always kinder to put her out of her misery. Put her down. Which is never easy as you always remain optimistic, keep treating the condition in the hope she may cast her lambs and rally, you have spent days nurturing the beast, hoping and praying that she will show some signs of rallying but there comes a time when realisation dawns and you know you have to do the right thing, let her leave this world peacefully, call the dead cart and pay £14.25 for the privilege.

There have been many reports of incidences of twin lamb disease, the weather has got to be a contributing factor, fields bare as a board - there is no substitute for the real thing, sheep are meant to eat grass and this year so far there is none. Those already lambing away further inbye are reporting problems due to there being nothing in the fields to turn the ewes out on to, these being fields that haven't been grazed for quite some time, fields that ought to be freshening up, growing grass and giving the ewes a boost as they are set out into them. The weather is due to warm up this week according to the forecast, hopefully this ought to set the grass on growing and give the sheep a sporting chance of remaining healthy.

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