Borna disease, also known as contagious encephalomyelitis or head disease of ungulates, is a rare viral disease of the nervous system that mainly affects horses and sheep. However, other animals and humans are also susceptible to the Borna virus. The disease was first described in 1813, when a whole group of cavalry horses fell ill in the town of Borna.
The disease is caused by the Borna Disease Virus (BDV), a pathogen similar to the distemper, rabies, and measles viruses. The virus is present in the saliva and eye and nose secretions of infected animals, but also in their urine.
For a long time, it was assumed that transmission occurred through direct contact between animals. According to the latest scientific studies, small rodents, especially the common shrew, serve as a reservoir for the pathogen. It is therefore assumed that horses do not infect each other through contact, as previously assumed, but by sniffing infected mice. The virus first enters the olfactory region of the brain via the mucous membranes of the nose and throat. This would also explain the low regional spread of the disease, as common shrews always remain in the same area.
Borna viruses primarily attack the limbic system, the area of the brain that controls emotions and instinctive behavior and releases endorphins (the body's own opioids). This is where the pathogen multiplies and inflammatory reactions occur. It is also suspected that the virus causes an imbalance in brain neurotransmitters.
After an incubation period of several weeks to months, the exact duration of which is not known, a wide variety of clinical signs may appear, depending on the region of the brain affected. The most commonly observed symptoms include a wide range of behavioral changes, movement disorders, depression, empty chewing, nervousness, aggression, increased skin sensitivity, and teeth grinding.
Affected horses often push against walls or walk in circles, tremble, and may collapse. As the disease progresses, apathy, convulsions, and increased salivation occur. The final stage of the infection is characterized by recumbency, rowing movements, and fever spikes, eventually leading to death.
Due to the diverse and rather unspecific symptoms, which can also be signs of other infectious diseases such as rabies, herpes or botulism, diagnosis is not always easy for the veterinarian. After a thorough clinical examination and a detailed preliminary report from the owner, the veterinarian will be able to express an initial suspicion. Further blood or cerebrospinal fluid tests can be carried out to confirm the suspicion by providing possible evidence. However, the detection of antibodies in the blood serum alone is not sufficient, as this only indicates that the horse has already had contact with BDV.
A definitive diagnosis can only be made after the animal's death. In the histological examination of the brains of horses with Borna disease, the pathologist can find special inclusion bodies in the cell nuclei of the nerve cells, which are considered evidence of a Borna virus infection and are primarily detected in the olfactory brain.
Based on current knowledge, there is no known treatment that can cure the disease. In the event of an acute infection, the veterinarian can only attempt to alleviate the symptoms. In most cases, the disease leads to the death of the animal. Horses that survive the acute phase of the disease usually suffer from lifelong behavioral disorders.
Once the disease has broken out, there is little chance of recovery and it almost always ends in the death of the animal. Horses that have been tested positive for BDV antibodies but show no symptoms are referred to as seropositive animals. These animals are merely carriers of the virus and have a significantly better prognosis than horses that have fallen ill.
It is not possible to reliably prevent infection with the Borna virus. However, as the significance of the Borna virus for humans is still unclear, strict hygiene measures should be observed when handling animals that are likely to be infected.
However, Borna disease is particularly common in certain areas. These so-called endemic areas include Saxony, Saxony-Anhalt, Thuringia, Hesse, Baden-Württemberg, Bavaria, and Switzerland. For a long time, it was therefore recommended that horses from these areas be tested for the Borna virus before being transported to other areas. However, given that the most likely route of transmission is now believed to be via the field vole, this recommendation is no longer valid.
What is a fun night of dancing for many people is unfortunately a sensitive issue for a lot of dog owners: New Year's Eve fireworks frighten our noise-sensitive four-legged friends and can lead to major problems.
Uveitis is an inflammation of the uvea, the middle layer of the eye. It can be divided into anterior and posterior inflammation and manifests itself through a narrow pupil and reddened conjunctiva.
Due to its appearance, the neck lump is also known as a talpa, which means mole tumor. It describes all inflammatory enlargements of the soft tissues in the neck area of the horse. The majority of cases are due to inflammation of the bursa located under the neck band.
Fancy a little fun and games with your rabbit? Rabbits are intelligent animals. With patience and the right steps, they can even perform a "high five" or "sit."
The cuddly soft chinchillas are nimble climbers and jumpers. They are great fun to watch. And with a little patience, they will even become tame!
Thanks to improved preventive care, senior dogs are no longer a rarity. Similar to humans, they suffer from classic age-related ailments such as osteoarthritis, cataracts, and dementia. Around 20% of nine-year-old dogs and almost 70% of 15-year-old dogs suffer from dementia, also known as canine cognitive dysfunction syndrome (CDS or "dog Alzheimer's").
This little-known neurological disease of the spinal cord and spine mainly affects older, large dogs weighing 20 kg or more. The disease develops very slowly but is very painful for the dog and causes progressive paralysis in the hindquarters.
Periodic eye inflammation has been known for over 2000 years and is the most common eye disease in horses. It describes a recurring inflammation of the middle layer of the eye (uvea) in horses. In veterinary medicine, the term "equine recurrent uveitis" (ERU) is now used. The disease occurs repeatedly, initially at longer intervals and later at shorter intervals, and can lead to significant visual impairment. Since the affected horses often went blind from this disease and it was suspected that it was related to the phases of the moon, it was also commonly referred to as moon blindness.
Skin diseases are one of the most common reasons for visits to the vet, alongside gastrointestinal disorders. Pyoderma refers to purulent infections of the skin caused by various bacteria. In healthy animals, the skin provides good protection against infections through various defense mechanisms. There is a balance between the normal microflora of bacteria, yeasts, and parasites on the one hand, and the formation and breakdown of skin cells and their waste products on the other. The microflora feeds on the waste products of the skin and at the same time prevents the colonization of infectious germs.
It happens in the paddock or even in the stall: your horse injures itself and may be bleeding. What should you do? Is it just a small scratch, a bump, or even a huge, gaping wound? Do I need to call the vet, or can I treat it myself, and if so, how? How can I minimize the risk of injury in the future? Kicks, bites, falls, or foreign objects can cause cuts, puncture wounds, abrasions, bruises, contusions, or burns in horses, which may require veterinary treatment depending on their severity. The severity of an injury always depends on its location and the involvement of surrounding structures, such as muscles, tendons, or joints. As with humans, a distinction is made between covered and open injuries in horses. In covered injuries, the horse's skin is undamaged, which is why this type of injury is not always easy to detect. For example, a kick may have caused a bruise that we as owners may only notice when grooming or when the horse is lame. Damage to the skin is referred to as an open injury or wound. This results in bleeding of varying severity, but even here, smaller wounds can be overlooked due to the coat.
Is your dog moving more stiffly, reluctant to go down stairs or jump into the car? Is he limping or does he have a swollen joint? Around 20% of all dogs develop joint diseases such as arthritis and osteoarthritis during their lifetime. But what is the difference between them?
Ear infections in dogs are one of the most common reasons for visits to the veterinarian. However, the condition is often detected too late and not treated consistently. The anatomical structure of the ear canal in dogs and its length make it prone to inflammation. Due to various factors, some dog breeds are even more susceptible to inflammation in the ear area. Outer ear infections, also known as otitis externa, are the most common type. Middle and inner ear infections are less common. However, if not detected early, these can develop into chronic conditions that require intensive treatment.
