Bluetongue Control in Europe

At a recent seminar about the spread of Bluetongue (BT) in Europe it's crystal clear that the disease had a devastating effect in 2007, and in the countries with no defined winter period such as Spain and Italy, continues to have cause significant losses in cattle and sheep. In Holland and Belgium, a compulsory vaccination policy for the summer of 2008 brought about a massive reduction in the outbreaks of disease and hopefully halted the spread of infection to neighbouring countries. Unfortunately neither of these countries has plans to continue with compulsory vaccination, and it is to be hoped that the livestock owners will continue to vaccinate in sufficient numbers to achieve the 80% vaccination target needed to halt spread. France is an important country to the UK in terms of threat of disease spread. Last year some 40 million doses of a BTV8 vaccine were used in France to control disease; despite these numbers disease was widespread in central and southern areas. The only areas to escape disease was northern France, where an aggressive vaccination campaign was successful in controlling disease; this area had suffered big BTV losses the year before and were ready for it in 2008. Complacency and failure to vaccinate cost French livestock producers a great deal.

Much concern was raised about the future roll of the 2 new strains, 1 and 6. The case of BTV1 now in Brittany was imported from the south of France, and the case of BTV6 in Belgium was picked up on a routine abortion screen. It appears that both these strains might show only limited spread in an area and might not be capable of causing such severe disease as BTV8. If they indeed only spread slowly then rapid identification and local movement restrictions will help contain any outbreaks.

Much research is being done on new BTV vaccines - as it stands it is likely that the very safe and effective inactivated vaccines currently in use will be all that is available for some time, and probably protect against only one strain. It is hoped improved vaccines will be low cost, be able to distinguish between vaccinated and infected animals, cover many different sero-types and be in a single dose. 

To summarise - midges are the way this disease is spread, and BTV infected midges will make it to the UK. BTV8 crept into the UK via imported animals, and unless movements are voluntarily restricted, could happen again. Vaccination works.

Calf Scour Risk Assessment

With this newsletter is a scour risk assessment form Intervet Schering Plough, the makers of Rotavec Corona, the market leading scour vaccine for beef and dairy calves controlling scour caused by E.coli, Rotavirus and Coronavirus. Given approximately 1 month pre-calving (but in cases of an outbreak protection had occurred in 10 days) it is a superb vaccine in the control of these infections. I apologise for the late delivery of the assessment forms, but they were late in reaching the practice. The main reason for sending them out is the chance to win a really excellent cattle crush. Downside is you have to give your personal details to the company, but if you fancy a chance to win the crate complete the forms and drop them into the practice, we will take care of the final posting. The information you give on how you handle your calves will remain with the practice. If you have already received a form directly please ignore this one. For April calving cows it is still not too late to vaccinate with Rotavec Corona: flexible and convenient - superior and prolonged protection - only single shot scour vaccine available.

Calf Scour Diagnostics

From the same company we have a supply of calf scour test kits. They allow us to test within 20 minutes samples of calf scour for evidence of the 4 main causes of scour - E.coli, Rotavirus, Coronavirus and Cryptosporidium. It's vital you know what is going on, early diagnosis could allow you to vaccinate in the face of even a moderate outbreak (costs of £3000 for a 100 cow herd), use preventative antibiotics to reduce E.coli infections and in the case of Cryptosporidiosis change to the only effective treatment. As ever fluid therapy is the cornerstone of any scour treatments, and Effydral tablets still come tops for ease of use and effectiveness. Depending on the degree of dehydration calves will need a minimum of 4 litres daily and in some cases up to 8 litres per day, in feeds of 2 litres at a time. If a calf can't stand or is very wobbly then an i/v drip will be required to give any hope of recovery. These kits are free to use, compared to £25+ in other labs. We can either do the testing on the farm or you can bring samples to the clinics. Please use this resource, it will help control disease and improve calf survival and performance. 

Lambing Notes 

What's going on so far? Enzootic still top of abortion agents, but recently a few outbreaks of Campylobacter infections. It is vital to isolate/remove aborted ewes and set up between pen hygiene to stop spread of disease. Despite the poor weather twin lamb disease has not been a huge issue in general, but had caused individual losses. It's usually been in hard up twins, and as ever treatment has been difficult and results poor. Early days yet but few reports of watery mouth, Spectam Scour Halt does seem to work well, and as yet few reports of any major problems with joint ill. Remember if you have any questions or concerns about any livestock issue then please give your usual vet a call.

April Newsletter

I have to apologise for the unusual newsletter presentation last month. The newsletter starting with Bluetongue Control was meant to be sent out with the Rotavec Corona cattle crush flier - this didn't happen so some of the articles may not be as relevant as then but some elements might be of use. Good news to start this month. Natalie gave birth to a baby boy last week, Ewan James, a brother for Eleanor Rose. We are delighted for Natalie and Alasdair and wish them all the very best for the future. Hopefully we will see the family at Kelso before too long. Although taking an extended break from practice Natalie is running the Merlin website and can be contacted on the web link.

New Wormers for Cattle and Sheep

Cydectin LA for sheep - useful product for "lambing worm dose" giving 97 days hoovering effect - effectively the ewes hoover up the larvae on the pasture, reducing the challenge for the lambs in early-mid summer. This can mean that lambs may never need wormed if they go for slaughter before mid summer. Won't control Nematodirus so watch out for that one. This product also very useful for treatment of sheep scab, single injection preventing re-infestation for 60 days, allowing sheep to be returned to infested pasture straight after treatment. The product must be administered with an approved applicator at the base of the ear. Withdrawal period is long at 104 days, so use only with caution in feeder lambs.

Cydectin 10% LA for cattle - an effective alternative to Autoworm boluses, especially for autumn born calves at turnout. Single injection at the base of the ear gives up to 150 days protection against gut worms (varies with species), and 120 days protection against lungworm. Withdrawal period at 108 days is much less than the boluses, so could give you more versatility. Both Autoworm and Cydectin 10% LA work most effectively if cattle are set stocked.

For lighter beasts there will be a cost saving using Cydectin LA compared to the boluses. If interested vets will demonstrate the injection process on farm. (M Kyle)

Bull Semen Testing

Just getting into the season, appointments being taken daily. So far bulls have been testing well, especially those kept in small groups; the natural aggression seen in these situations encourages good physical conditioning, a good flushing effect to remove "old" semen from the pipework, and helps establish good semen production in the testicles. If kept in groups bulls need to be of a similar age and size. At approximately £2 per cow mated having confidence that all your bulls are up to scratch will give you peace of mind and set the scene for a successful mating period. To cope with demand Dave and Neil at Kelso and Pete at Gala have been getting training in the technique. It looks like David will be back working at Gala from the middle of May, will be good to have him back on the farm team.

Bluetongue Vaccination Deadlines

The April 30th deadline for completing vaccination draws close. For sheep needing only a single injection the end of the month must be your target for all sheep over 3 months at that time. For cattle the initial priming injection should have been given by now. Latest figures are that 5.5M doses have been used in Scotland, out of a population of approximately 8M to be vaccinated. This gives a figure of just under 70% which is a great achievement by Scottish Livestock owners. The last 3 weeks of April should lift that figure close to the necessary 80% coverage needed to effectively control the disease. This will leave 4M doses of the subsidised Merial vaccine for use during the summer.

What to do in the summer? So much will depend on how the disease behaves in Europe and England. If the French in particular adopt a very strong and robust vaccination policy then all of Europe will benefit. However Holland and Belgium have lifted compulsory vaccination so disease could re-appear there big style. Despite a compulsory programme in Germany disease has been recorded in March. So the risk to Scottish calves and lambs will still be very real. As it takes time for calves to develop a full immunity after vaccination then a wait and see policy is of little use. Advice must be to protect your calves and lambs as best you can - there will be hundreds of thousands unvaccinated lambs and calves on the ground by the end of June, just when disease can be expected. Different vaccines allow vaccination at a younger age - this may tie in easier with other management handlings - but the price is not subsidised. Best bet is to give your usual vet a call to go through the options.

Strep Joint Ill in Lambs

This is a real horror story for some flocks. Conventional joint ill develops when bugs get into the lamb via the navel. From there the bacteria spread into the joints and cause what we see as classic joint ill. Strep Dysgalactia infection is very different in that it occurs in flocks that have a high level of hygiene in the lambing shed and follow on fields. So despite double dipping navels, controlling watery mouth, keeping pens clean and disinfected between lambings, making sure all feeding tubes are clean and disinfected, many many cases of joint ill develop. Can be as many as 10% of lambs. The infection is oral, and is not influenced by achieving high hygiene standards. The bacteria are present in and on ewes, and the lambing areas quickly become contaminated. So far practical prevention relies on giving antibiotics to all lambs at birth by injection in high doses. This is not a substitute for the oral prevention of watery mouth. If you think you may be getting cases of this disease it is vital you speak to us about prevention. We need to establish a diagnosis at the lab. We plan to see for future years if a vaccine can be prepared. If so we will need a culture of the bacteria from lambs on your farm. Another test is to blood sample some affected lambs when 3 months old for evidence of Erysipelas infection. This disease has a high impact on profitability and is a major welfare concern for affected farms.

Bravoxin 10 - a new 10 way Clostridial Vaccine

Clostridial diseases are among the oldest diseases known to livestock and farmers. The bacteria responsible are found everywhere in the animals environment. They form resistant spores that can lie dormant for decades. These spores are consumed by cattle and sheep where they lodge in the muscle tissues around the body. When some bruising (can be as simple as running up a race) occurs the reduced oxygen supply to that area allows the spores to develop and create severe toxins, and we see diseases such as Blackleg, Braxy and Tetanus. There is no cure for these conditions. Often death occurs without warning. These carcasses tend to bloat very quickly and to extreme levels.

Often the infection appears after routine tasks such as dehorning, castration, even after simple I/M injections. Sudden feed changes causing acidosis can damage the rumen wall and allow the diseases to develop. Dairy cattle with ulcers often die suddenly due to Clostridial disease.

Vaccination in the UK has never really caught on, but with the increasing value of cattle and the rising costs and hassle of disposal perhaps we need to consider herd vaccination more closely. The new vaccine Bravoxin 10 has been developed to protect against the important Clostridia - a small two dose programme in cattle might just be the answer to stop the all too common sight of a dead beast at point of finishing or a dead cow in the autumn nursing her young calf. Avoiding the death of a single finisher could cover the costs of vaccinating 500 cattle. Again please give your usual vet a call to discuss further.

 

 

 

 

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