Suicidal poisoning with mercaptodimethur-morphological findings and toxicological analysis.

In the western countries, the number of fatal intoxications with plant protecting agents has decreased to some extent due to laws restricting the use of highly toxic pesticides like halogenated hydrocarbons. Nevertheless, in consideration of the easy availability of most plant protectants, the small fraction of such fatalities among suicides and intoxications is astonishing. An 80-year-old woman died of an intoxication with methiocarb (mercaptodimethur), a carbamate type pesticide and as such a reversible inhibitor of the acetylcholinesterase. The case is presented because it is the first explicit report on a fatal poisoning of a human with methiocarb. The methiocarb concentrations detected were 6,100 microg/g in stomach content, 4.0 microg/ml in heart blood, 11 microg/g in kidney, 1.9 microg/ml in urine, 25 microg/g in liver, 2 microg/g in bile and 2.5 microg/g in brain tissue.

A suspected case of intermediate syndrome in a dog with carbamate toxicosis.

CASE REPORT: A 7-year-old female spayed Labrador Retriever was managed for suspected carbamate toxicosis after confirmed ingestion of a large amount of methiocarb. Therapy included decontamination, supportive care and management for aspiration pneumonia. On the third day of hospitalisation, after an initial clinical improvement, the dog developed respiratory muscle weakness, inspiratory dyspnoea and pronounced cervical muscle weakness. These delayed clinical signs were consistent with the 'intermediate syndrome' described in some cases of organophosphate and carbamate toxicoses in humans and also described in one case of organophosphate toxicosis in the dog. Intermediate syndrome has not been reported in carbamate toxicosis in the dog. CONCLUSION: This case report highlights the necessity for veterinarians to monitor for additional complications not commonly considered in acute carbamate toxicoses.

Avfail in color avoidance learning by starlings (Sturnus vulgaris) and red-winged blackbirds (Agelaius phoeniceus).

Certain unconditioned stimuli (UCS) in flavor avoidance learning sometimes become ineffective after pairings with relatively stronger UCS. This failure of avoidance learning (avfail) has been demonstrated only with rodents. The present investigations were conducted to determine whether avfail might also occur with avian species, the food selection of which is guided primarily by visual cues. In Experiment 1, starlings were given pairings of methiocarb (a relatively weak UCS) and LiCl (a relatively strong UCS). In Experiment 2, red-winged blackbirds were given pairings of two concentrations of methiocarb (relatively weak and relatively strong UCS, respectively). Pairings were followed by a conditioning trial (UCS gavage in the presence of a color cue) and two-choice tests. Conditioned avoidance was always observed except when methiocarb preceded LiCl and when the low preceded the high methiocarb dose in preconditioning pairings. Experiment 3 demonstrated that UCS habituation could not account for the results of Experiments 1 and 2. The data reflect avfail in the visual modality, and a biological implication of the results is that birds may not learn strong avoidance of aposematic prey containing varied levels of toxicant.

Pesticide poisoning of livestock: a review of cases investigated.

The cases of suspected poisoning of livestock by a range of organic chemicals, mainly pesticides, investigated at the Central Veterinary Laboratory during the period 1977 to 1980 are reviewed. The incidences of poisoning by various types of compound and the species most at risk are discussed. Organophosphorus pesticides and rodenticides were the commonest causes of poisoning. Pesticides accounted for one in 25 of all fatal poisonings listed by the veterinary investigation diagnosis analysis (VIDA) of the Ministry of Agriculture, Fisheries and Food.

Epidemiological features of snail and slug bait poisoning in dogs and cats.

Snail and slug baits were the most common cause of poisoning in dogs and cats in a survey of 34 veterinary practices. During a 7-month period, 280 dogs and 12 cats were poisoned by metaldehyde (57%) or methiocarb (43%) containing baits with case fatality rates of 8.1% and 9.1% in dogs and 16.7% and 50% in cats, respectively. The ages of poisoned dogs ranged from 2 months to 17 years and cats from 3 months to 5 years. There was no decrease in frequency of poisoning or case fatality rate demonstrated with increasing body size in dogs. Poisoning was most frequent in the month of October. Baits were eaten off the ground or obtained from storage areas, often despite a variety of preventive measures. It is suggested that these products should be reformulated to make them less attractive to domestic pets.

Methiocarb poisoning of a horse in Australia.

Snail bait poisoning is rare in horses. Cases have been reported, but clinical signs and subsequent prognostic indicators have been poorly documented and must be extrapolated from cases in companion animals. We describe in detail the poisoning of a horse that consumed a lethal dose of the carbamate, methiocarb. There are currently no guidelines for treating equine methiocarb toxicoses, but the principles of management are based on supportive therapy.