Lead Poisoning

Calves and lambs like to investigate new things that they come across and this can sometimes leave them vulnerable to poisoning. When the rumen is first developing it will readily absorb lead and other things that would not normally get into the blood stream. Animals find lead from the soil if heavy rains have disturbed the sediment from streams in the winter or contaminated ground has been dug over. Lead is also present in discarded batteries and older painted wood, it is particularly dangerous if any of these things have been burnt on the farm as calves and lambs are attracted to the ash.

Available Treatments

Animals that have been exposed to lead will become agitated, they often have uncontrolled muscle tremors and they may get stuck in corners as they have a tendency to loose their sight. At this stage we can usually get a good response to treatment. There is a drug called sodium calcium edatate that is given into a vein and binds to the lead in the blood stream so that it can be excreted through the kidneys. This will sometimes need to be repeated if the animal is still absorbing lead that is in the gastro intestinal tract. Once lead poisoning has been diagnosed temporary restrictions will be placed on the animals concerned so that they cannot go for human consumption. This does not usually cause too many problems as affected individuals are likely to be young and the risk of contaminating the food chain will be long gone before they are ready to leave the farm.

Live Fluke

From time to time even now we come across flocks that are suffering losses because of the fluke infection they picked up in the wet summer last year. Sheep give few indications that they are carrying fluke. If you are vigilant you might notice the membranes around the eye are pale, sometimes there will be swelling under the jaw, but the usual thing is to have an unexpected death either at lambing time or when the lambs are two to three weeks of age. It is always worth investigating ewe losses as this is a problem that can be resolved fairly easily.

DNA Testing for Cattle

When we are tuberculin testing cattle it is not unusual to come across animals that do not have a passport. BCMS seem to be inflexible if they receive a passport application after the 27 day deadline from time to time items do get delayed in the post and it is not easy to have proof of postage for all of the applications you make. Forensic science has move on a long way in the past few years and it is possible to identify individuals from just a few cells. This technology can now be used to prove the identity of a calf that does not have a valid passport, as long as the mother is still in the herd. Once you have the relevant form from BCMS we will need to come and take hair samples from both the cow and the calf so that the DNA of the few cells around the roots of the hairs can be compared from the two animals. This seems to be the only way to get a passport for unregistered cattle so that they can eventually get into the food chain.

Pig Flu

There is a great deal of interest in the flu epidemic that is spreading across the world. The flu virus does have the ability to mutate and sometimes pass between different animal species. Pigs do get type A influenza from time to time, but there have been no reported cases in the UK in recent months. It has been reported that the Swine Influenza virus that circulates in Europe have a different antigenic and generic make up to the ones seen in America. The H1N1 strain that is causing all of the interest seems to have elements from the pig, avian and the human flu virus. The exact origin of the infection in Mexico is unclear at the moment. This variant has never been isolated in pigs any where in the world. Until now it was not thought that pigs with influenza could pass the infection onto people, so there is no official monitoring system. Urgent investigations are under way. The decision of Egypt to slaughter all of the 300,000 pigs in the country does seem to be a bit of a panic reaction that is not based on any scientific facts.

Transmission

It would seem that this virus is readily transmitted between people and it is frightening how quickly it has been able to travel around the world. So far the only good thing about it is that it seems to be a mild disease outside of Mexico. This might be the way that some strains lose some of their virulence each time they are passed onto a new host. Another positive factor is that for people at least influenza is a seasonal problem in the winter and weaker strains do not tend to get established so readily in the summer months. We have been expecting a flu epidemic for some time, the one that was most feared is the Avian H5N1 strain as this is a virulent virus if it should find a way of infecting people. It is fortunate that the current strain that have been introduced is easier to deal with.

Itchy Horses

Sweet itch is a problem that affects thousands of horses each summer. It has been estimated that 5% of the UK horse population are affected to some degree. It is caused by an allergic reaction to the saliva of the culicoides midge. It the summer the female midge needs a blood meal before her eggs can mature. The midge will breed from late March through to the end of October, they seem to start breeding earlier after mild winters. Most horses will tolerate a few midge bites, it is when the numbers build up that problems occur. They do not like to fly in strong winds, when there is heavy rain or in bright sunlight. That is why they are most active at dawn and in the evenings. Midge numbers will increase dramatically during the summer when there have been wet spells interspersed with drier periods.

Sensible Precautions

It is a sensible precaution to try and limit the number of midge bite all horses are exposed to because once they have developed a sensitivity to the insect this will continue for the rest of their lives. In the summer if you can make the best use of exposed fields where there is minimal shelter and avoid fields next to muck heaps and wooded areas. On still days use your stable in the evening and over night as this significantly helps to reduce exposure to the bites. If none of this is possible use an insecticide. Benzyl benzoate is still available although it should be applied to the mane and tail head every day. Switch is an insecticide that you can pour onto the skin that should last for at least a week on most animals in dry conditions.

Cover up

If your horse has developed sweet itch long acting cortico steroids can sometimes help in an emergency to relieve the itching. The most effective way to stop midge bites is to use a Boett blanket. Most horses readily adapt to a midge blanket and are not troubled by biting flies when they are wearing one.

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