Bird Flu in China

It is reported that a new strain of bird flu H7N9 has infected over 100 people in China, twenty two patients have died because of the infection. Bird Flu epidemics often seem to start in China, where they have a large population of both poultry and people. Birds are often sold live at street markets so there are many opportunities for animal diseases to spread to people.

The new strain of Bird Flu is a cause of concern because it does not seem to have many adverse effects on poultry, they can carry the infection and not show any visible signs of illness so it is difficult to identify birds that are carrying the disease. Initial cases of the H7N9 were seen in Shanghai, it has now been found in Beijing and five other provinces. Scientist are having problems tracking the spread of the infection they think it is spread directly from poultry to poultry as they have so far failed to find the virus in wild birds. At this stage it is not clear how the virus is spreading. More than half of the patients have had no known contact with poultry and it is by no means clear if the disease is spreading person to person although this is the way that most flu viruses propagate.

The new virus is made up of components from three other virus strains found in birds from Asia. Available vaccines give no protection against this new virus and it will take several months before a vaccine can be developed to control it.

Bird Flu in Suffolk

Meanwhile a farm in Suffolk has been put under movement restrictions as Bird Flu has been discovered in a group of Turkeys. Investigations show that the strain involved is not either the H5 or the H7 strains that are potentially serious for humans. It is not though that there have been any significant losses, but all flu like diseases in poultry have to be investigated until it can be determined that they are safe.

Reporting Cattle Abortions

I have been asked by Animal Health Veterinary Laboratories Agency to remind you that you must report all cattle abortions to the Stafford Office by phone on 01785231900. It is for them to decide if samples need to be taken and an investigation is carried out. There are different rules for animals that have not originated from the UK and they are likely to ask for samples from animals at a first abortion that have aborted at a show or market

Further Investigations

Samples are normally taken if the animal was born outside of GB or Northern Ireland, has had no previous normal calving in the herd or when there was a previous abortion or premature calving in the herd within the past 30 days. Sometimes samples are taken if you are a herd that is thought to be at risk of exposure to Brucellosis.

 Problems from Silage.

At the moment we are getting reports of abortions because of Listeria from poor quality big baled silage, but these should decline now. There is a danger that Brucellosis will re emerge from imported breeding cattle and get established here as our cattle have no resistance to the disease.

Disclosing Infected Farms.

Farmers in South Wales are being asked to sign a disclosure if they go down with TB to allow AHVLA to tell their neighbours that they have lost their disease free status. I wonder if this is necessary as the chances are it will be something that they will already known and it would not encourage them to do anything different. Also there is a danger that the press and general public will hear about these breakdowns and, not understanding the disease process, making things even more difficult for those who are unfortunate enough to have infected animals at the moment. Perhaps it would be better to draw attention to the real culprits and put up posters in villages and roadsides warning of the presence of infected badgers in the area.

Laminitis

After the long winter the hope now is that the temperatures will improve and the grass will finally start to grow. When this happens it should start to ring alarm bells for horse owners as there is a high risk of you seeing laminitis. If you are unfortunate enough to trigger a flare up of laminitis you might end up treating it all summer so it is best to be careful now so you can relax your guard for the rest of the year.

Why it happens

The main cause of almost all laminitis is poor digestion of rich grass. Fertilised grass is particularly dangerous and fat ponies are the most at risk. Rapidly growing grass contains sugars called fructans that are not easy for a horse to digest. Fructans break down to  acids and toxins which leak into the body and damage blood vessels.  When blood vessels that feed the feet are affected in this way the amount of blood flowing down to the sensitive laminae is reduced and they become swollen, inflamed and very painful. Damage to the laminae means that they cannot do their job of holding the pedal bone in place properly and this results in pain. As the situation gets worse and if the flow of toxins is not reduced then the laminae can be so damaged that the pedal bone sinks through the sole of the foot and it might not be possible to salvage the situation.

Non Grass Causes                                   

Rarely grass is not the cause of the problem. Probably the most common ‘non-grass’ causes of laminitis is a disease caused ‘Cushings Disease’.  Many of the rare cases of laminitis that do not respond to normal treatment do so because of this problem.  Cushings disease is caused by a growth on the part of the brain, which controls the body’s normal production of steroids.  This condition is mostly seen in older individuals and the high levels of steroids in the body directly cause laminitis.  Cushings disease can be treated effectively.                         

Steroid Release.                                    

 In recent times other explanations have been put forward that explain the cause of laminitis in more detail.  In fat ponies the fat that is laid down disturbs the body’s metabolism and releases chemicals similar to steroid hormones.These steroids make the horse or pony even more prone to getting laminitis and the condition is often called ‘metabolic syndrome’. In addition, changes to the horse’s metabolism often mean that a hormone called insulin does not work properly.  Lack of good insulin causes diabetes but in horses with laminitis insulin does not work properly meaning that blood sugar levels get too high.  In this situation horses are said to be ‘insulin resistant’.  High levels of blood sugars damage cells in the laminae and make horses more prone to getting laminitis.Other rare causes of laminitis include: overeating grain, concussion from excessive work on hard surfaces, metritis and stress which can again release steroids into the blood stream.   

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