Search results
Results from the WOW.Com Content Network
Pythiosis is a rare and deadly tropical disease caused by the oomycete Pythium insidiosum. Long regarded as being caused by a fungus, the causative agent was not discovered until 1987. It occurs most commonly in horses, dogs, and humans, with isolated cases in other large mammals. [1]
The disease is almost always seen in grazing animals, although there are isolated reports of the condition occurring in stabled horses. Grass sickness is most frequently seen in young horses aged between two and seven, and is particularly prevalent during April, May and June, and later in the autumn, after a spurt of grass growth.
An acute form of the disease, which is generally fatal unless treated, occurs in horses, donkeys, mules, cattle, buffalo, deer, camels, [2] llamas, dogs, [3] and cats. This form is caused by Trypanosoma evansi (Steel 1885) (Balbiani 1888), and is transmitted by horse-flies, and also by the vampire bat, Desmodus rotundus, in South-America.
Pituitary pars intermedia dysfunction (PPID), or equine Cushing's disease, is an endocrine disease affecting the pituitary gland of horses. It is most commonly seen in older animals, [ 1 ] and is classically associated with the formation of a long, wavy coat ( hirsutism ) and chronic laminitis .
Obese horses are usually fed hay at a level of 1.5% ideal body weight, which may be dropped to 1% of body weight if no weight loss is realized after 30 days. However, feeding less than 1% of body weight in forage is not recommended, since secondary problems such as hyperlipemia and stereotypies can occur, and insulin resistance may actually be ...
The disease has a similar cause to Hirschsprung's disease in humans. A mutation in the middle of the endothelin receptor type B ( EDNRB ) gene causes lethal white syndrome when homozygous . Carriers, which are heterozygous —that is, have one copy of the mutated allele , but themselves are healthy—can now be reliably identified with a DNA test .
Horses that develop purpura haemorrhagica usually have a recent history of strangles (infection with Streptococcus equi subsp. equi) or vaccination (intramuscular or intranasal) for strangles. It is thought to be caused by an auto-immune reaction where antibodies against the S. equi M- or R-protein cross-react with proteins on endothelial cells .
However, any horse that can store excess amounts of glycogen, usually genetic, can develop this form of ER. [1] Recurrent Exertional Rhabdomyolysis (RER) is commonly found in breeds that are high strung such as Arabians and thoroughbreds. However, any horse can develop this type of ER if it displays abnormal muscle contractions. [1]