Jagadeeswaran Appusamy

Lead poisoning in livestock             Lead poisoning in animals and people is a major concern worldwide.             Poisoning in animal populations may serve as a sentinel to assess the extent of environmental contamination and human health problems related to lead.             In veterinary medicine, lead poisoning is most common in dogs and cattle. Lead is the most common cause of cattle poisoning. Lead poisoning in other species is limited by reduced accessibility, more selective eating habits, or lower susceptibility.             Animals die or perform poorly after accidentally ingesting lead. Gradual poisoning may also occur in areas with heavy industrial pollution. Causes           Old lead acid batteries are the most common cause of lead poisoning in livestock. Battery cases become brittle over time and are easily broken by inquisitive cattle. The lead and lead salts that they contain are easily accessed and readily eaten by stock. One broken tractor battery

MERCURY TOXICITY Epidemiology Sources of poison §                   Contamination of herbage and water by mercurial effluents from the metallurgy. §                  Accidental ingestion of seeds treated with mercurial fungicides (viz., phenyl-, methyl- and ethyl- mercury compounds) and seed dressings. The commonest agent used is a dust of 5.25% methoxy-ethyl mercury silicate. Methylmercury dicyandiamide is also used. Treated seed is usually not harmful if it comprises only 10% of the ration and must be fed in large amounts for long periods before clinical illness occurs. A single feeding even of large amounts of grain thought to be incapable of causing mercury poisoning in ruminants but a fatal case has been reported in horse. §                   Inadvertent use of mercurial ointments for skin lesions (common in dogs/cats due to licking of wounds). The continued administration of a strong mercuric ointment to horses can cause poisoning by inhalation of mercury vapor b