Topic:Poisoning
Poisoning in horses refers to the ingestion, inhalation, or absorption of toxic substances that can adversely affect their health. These substances may include plants, chemicals, medications, or environmental toxins. Poisoning can lead to a range of clinical signs, from mild gastrointestinal upset to severe neurological or systemic effects, depending on the toxin involved. Common toxic substances for horses include certain plants like oleander and yew, heavy metals such as lead and arsenic, and specific pesticides or herbicides. This page compiles peer-reviewed research studies and scholarly articles that investigate the causes, effects, diagnosis, and management of poisoning in horses.
Poisoning with equine phenylbutazone in a racetrack worker. Phenylbutazone is a potent nonsteroidal, anti-inflammatory drug often used by veterinarians to treat racetrack animals. Its use in human beings is limited because of significant adverse effects and the availability of newer, safer drugs. We report the case of a 24-year-old man who ingested 17 g of equine phenylbutazone over a 24-hour period to treat the pain of a toothache. He developed grand mal seizures, coma, hypotension, respiratory and renal failure, and hepatic injury. Serum phenylbutazone concentration obtained approximately eight hours after presentation was 900 micrograms/mL. The pati...
[Animal nutrition for veterinarians–recent cases of clinical disorders in horses after intake of ionophore-containing feed]. Anamnesis and clinical signs of horses form five different stables after ingestion of ionophores are reported and techniques of feed examination are described. Within a few hours or days after feeding of new types or batches of concentrates horses fell ill. They showed colic-like symptoms with intense sweating and ataxia. Most of the sick animals died within a short time span. Samples of the concentrates were analysed and different types and amounts of ionophores were detected. In four cases contamination by monensin in concentrations of less than 5 mg to 679 mg/kg feed were found. One feed sa...
Mineral and vitamin intoxication in horses. Horses are subject to poisoning from many sources. This article considers poisonings from minerals and vitamins of nutritional significance and from minerals as environmental contaminants.
[Meadow saffron (Colchicum autumnale) in hay and colic in horses]. Following feeding of a new delivery of hay (bought in Southern Germany) 3 horses out of a unit of 17 developed colic within a few days one horse died. Post-mortem there was an intensive accumulation of serous or serous-haemorrhagic fluid in the thorax and abdomen. The hay was heavily contaminated by autumn crocus (colchicum autumnale)--about 1.48% of total mass. Other feedstuffs were of good quality and following removal of the affected hay no further cases of colic occurred. The pathological findings also indicated a colchicine intoxication.
Secondary gastric impaction associated with ragwort poisoning in three ponies. Poisoning with Senecio jacobaea (ragwort) is a common cause of chronic liver disease in horses in Britain. The major clinical signs are the result of hepatic failure but gastric impaction has recently been associated with the disease. The present paper describes three cases of secondary gastric impaction associated with ragwort poisoning. In each case the impaction was the cause of death or necessitated euthanasia.
The toxic factor in white snakeroot: identity, analysis and prevention. White snakeroot (Eupatorium rugosum Houtt) has been known to cause trembles in animals and milk sickness in humans since the American Revolution. It still continues to poison animals. Horses and goats are particularly sensitive to white snakeroot poisoning. Resurgence of livestock production on small farm units, and utilization of fresh raw milk may result in milk sickness; if the animals have white snakeroot exposure. The goat is the only animal with good toxicity threshold data. In other animals and humans the toxicity thresholds of white snakeroot are not known, and that until responsible t...
Cantharidin content of two species of Oklahoma blister beetles associated with toxicosis in horses. Cantharidin content of male and female Epicauta occidentalis and E conferta was determined. Aspects of the life cycle of blister beetles, taxonomy, pheromonal and adaptive functions of cantharidin relative to the medico-legal aspects of cantharidin poisoning, prevention and control in horses are discussed.
Black walnut toxicosis in ten horses. Black walnut toxicosis was diagnosed in 10 horses at one stable. The time from exposure to shavings to development of clinical signs was 8 to 12 hours. Most common clinical signs were moderate to severe laminitis (Obel grade 2 or 3), pitting edema of the distal portion of the limbs, and rapid respiratory rate. Two horses had clinical signs of colic and 2 other horses had anorexia and lethargy. All 10 horses recovered without complications.
Tremorgenic syndromes in livestock. Grasses that are essential components of livestock grazing programs sometimes are the source of tremorgenic toxicants to the animals consuming them. Morbidity can be high but mortality need not be if management closely observes the cattle daily and removes them at first sign of trouble. Specific treatment generally is not available nor needed. Survivors recover completely within a few days or weeks, except in chronic phalaris poisoning, where sheep and cattle may die after prolonged illness--or at least not make an economical recovery. Certain poisonous plants are responsible for tremorgenic s...
Alsike clover poisoning: A review. Trifolium hybridum (alsike clover) has been implicated as the cause of two diseases of the horse. One of these is photosensitivity, of which alsike clover is only one of a number of presumed causal agents. The other is a fatal syndrome which is known as "alsike clover poisoning" and which is manifest by progressive loss of condition, signs of hepatic failure, and varying degrees of neurological impairment. The underlying lesion of alsike clover poisoning is fibrosis and proliferation of the biliary tree. The experimental evidence implicating alsike clover as the cause of this syndrome comes en...
Monensin poisoning in horses – an international incident. Several hundred Michigan horses were accidentally exposed to varying levels of monensin. Severity of effects was proportional to the level of feed contamination; sudden death resulted on at least two premises. Acute signs of cardiovascular impairment occurred on one premises having received feed containing over 200 grams of monensin per tonne. Gross and histological postmortem lesions consisted of acute myocardial necrosis. Although only circumstantially confirmed, investigations led to the suspicion that the source of poisoning was a ration formulation error in a feedmill in southwestern Onta...
Iron toxicity in neonatal foals. Newborn Shetland foals died of acute hepatic failure following oral administration of approximately 16 mg/kg body weight ferrous fumarate. Lesions in these foals were indistinguishable from lesions in foals given an oral digestive inoculant containing ferrous fumarate and were also similar to the syndrome characterised as 'toxic hepatopathy' in foals in the United States in 1983. We conclude that foals are susceptible to toxicity from low doses of iron compounds in the first few days of life. Vitamin E and selenium deficiency may contribute to this susceptibility.
Salinomycin poisoning in horses. Six cases of accidental salinomycin poisoning in horses are described. The horses were fed a contaminated ration and presented clinical signs which were extremely varied in nature and severity. However, the range of signs, including anorexia, colic, weakness and ataxia bore similarities to those described in horses poisoned with the related ionophore monensin. Other similarities became apparent in serum biochemical profiles of the clinical cases. Although ionophore toxicity is rarely reported in horses they appear to be particularly susceptible, and it should therefore be considered as a diffe...
[Alder buckthorn poisoning in horses]. Seven cases of poisoning in horses are reported. This was caused by ingestion of branches of the alder buckthorn (Frangula alnus (mill.) syn. Rhamnus frangula L.), which had been thrown on the pasture. The biological characteristics and the toxic action of the plant are discussed more fully.
Clinicopathologic study of horses surviving pyrrolizidine alkaloid (Senecio vulgaris) toxicosis. Twenty horses of various ages had inadvertently ingested alfalfa hay contaminated with Senecio vulgaris. Among them, 4 died of liver disease. Blood was collected from affected horses at monthly intervals for 7 months and at the 9th and 14th months. The following serum enzymes and chemical items were assayed: aspartate aminotransferase, lactate dehydrogenase, alkaline phosphatase, gamma-glutamyl transferase, sorbitol dehydrogenase, total bilirubin, BUN, glucose, cholesterol, inorganic phosphate, calcium, total protein, and albumin. Amino acid profiles, conjugated bile acids, sulfobromophthalein...