Diagnosis of Toxicology
Diagnosis of poisoning in animals & birds is not easy task. Therefore ,it
should never be made in haste based on any signal observation. The first step
should be rapid assessment to the vital body function, particularly the
respiration & cardiovascular function. Once the vital signs are stable &
adequate , further evaluation of the poisoning may be taken up.
Diagnosis In case of poisoning may be of three types namely- tentative,
presumptive, confirmative base on the history, physiological examination of
the affected animals, circumstantial evidence , pathological & laboratory
observations & investigations & analytical evidence.
 History of poisoning:History of the poisoning should be extract from the owner of the animals.
Sometimes it may not to be possible to get all the details, or at times it may be
inaccurate & misleading . While taking history ,identity of the subject ,age
,toxic agent, its vehicle, how it has entered the body-through ingestion, spray
on the skin /dermal application, inhalation or parenteral route i.e. mode of
exposure, location of exposure, amount of exposure ,poisoning was accidental,
advertent, inadvertent or malicious & how mach time has elapsed between
exposure & onset of toxicity symptoms (latent period) & typical signs of
toxicity etc.
 -Physical examination and clinical evidence:Effected animal should be systemically examined for all body organs.
Observation of the vital clinical parameters namely-temperature, pulse,
 Organophosphate compounds induce hypothermia.
 Chlorinated hydrocarbon insecticides & belladona induce hyperthermia.
 Barbiturates & Mushroom poisoning cause bradycardia.
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 Belladona & cocaine cause tachycardia.
 Carbon monoxide ,hydrocyanic acid & fluoroacetate poisoning cause
increase respiratory rate.
 Narcotic analgesic & sedative poisoning cause decrease respiratory rate.
Similarly observation like miosis in opium poisoning, mydriasis in
belladona poisoning. dryness mouth, colour of urine and diarrhea,
constipation, ect. May aid in diagnosis.
 Circumstantial diagnosis:Through investigation of the owner regarding sudden change in feed
pasture, administration of drugs, pasture treatment with fertilizer or
herbicide ,spray of agrochemicals/pesticides on the animals or premises
painting of the building with lead based painting , then other containers of
agrochemicals ,petroleum production ,fertilizer, disinfected & rodenticides
containing some chemicals ect.
Similarly ,drinking water should note be ruled out as the possible source of
poisoning . higher levels of nitrite, fluorine, arsenic in ground water or the
contamination of water with salts, lead & industrial effluents
 Pathological evidence;Gross and microscopic examination of tissue organ aid in diagnosis of
some of poisoning case. Pathological investigation including necropsy
findings provide definite clue to the nature of poisoning &/or the system
involved & affected e.g.: Jaundice indicate hepatic damage.
 Cyanotic mucosa membranes indicate carbon monoxide, nitrite, nitrate
or chlorate poisoning.
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 Odor of the abdominal contents e.g. ;- bitter almond in cyanide & rotten
eggs in hydrogen sulfide .
 Color of the ruminal abdominal contents e.g. greenish blue in copper.
 Signs of generalized hemorrhage may indicate sweet clover poisoning.
 Laboratory investigation:Diagnosis of poisoning may be confirmed by routine hematological and
biochemical tests, the results of which further depend on the appropriate
biological samples.
 Analytical evidence;Confirmative diagnosis of poisoning of poisoning depend on qualitative
and quantitive detection of a significant amount of the toxic agent in biological
sample e.g. blood, faeces, vomitus, urine and environmental sample e.g. food,
forage, water & baits. Confirmatory diagnosis can only be made on the basis
of qualitative & quantitative detection of the toxicant in feed, water, ruminal
contents/gastrointestinal contents , animal blood or other biological samples.
 General
principles of the treatment of poisoning:-
Poisoning is always an emergency & need to be managed immediately with
appropriate measure using specific antidote whenever available. Intensity of
toxicity depends on the dose of poisoning & concentration at the
receptor/target site. Translocation of the drugs/poisoning depend on the
absorption, distribution, metabolism & excretion. In order to treatment the
poisoning cases effectively, a clear understanding of the basic principles of
toxiconkinetic, toxicodynamics & specific therapeutic goals is essential e.g.
absorption of toxic substances be minimized, antagonize the effects of
absorbed toxicants, metabolic biotransformation of poisoning with reduce
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toxicity be enhanced while biotransformation into toxic substances be
inhibited/reduce & elimination from the body be enhanced.
Gastrointestinal tract is an important site where from maximum absorption
of toxicant takes place. Thus, prevention of gastrointestinal absorption is an
important aspect in initial treatment of acute poisoning. It can be achieved
by :I. Removal of the poisoning from the stomach.
II. Hastening the passage through bowel.
III.
Neutralization of the poisoning within the gastrointestinal tract.
.
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Toxicity of agrochemicals
Pesticides:are any or mixture of substances intended for preventing, destroying
repelling or mitigating any pest. Pesticides are one of the most widely used
agrochemicals of toxicology importance, are also used extensively as
acaricides/ectoparasiticides in veterinary medicine to control insect pests of
both the animals & birds, pesticides are also widely used to control insect
vectors of public health importance.
A-Insecticides:Insecticides are a heterogeneous group of chemicals whose desired activity
is killing of insects in a very selective & specific manner. It, usually employed
as sprays-applied from ground or air, the hazard to man & animals occur due
to percutaneous absorption or by ingestion.
Common used of insecticides:I. Increase the production & quality of agriculture production.
II. To minimize the damage caused by insects during storage of food
grains.
III.
Control of ectoparasites of domestic animals.
IV.
Control of certain vector borne diseases.
V. Repel household pests & as anthelmintics.
B-Herbicides or weedicides:Are agents which are used to destroy undesirable plants/weeds e.g. dinitro
compounds,
Phenoxyacetic
acid(2,4-D,2,4,5-T),
(dalapon) ,Triazenes (Atrazine ,simazine ).
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chloroalipathic
acids
Class
Chemical nature
A-Insecticides
a-Organochlorines
Examples
I. Dichlorodiphenylethanes
DDT, dicofol aldrin, dieldrin,
II. Chlorinated cyclodienes
endosulfan lindane.
III. Hexachlorocyclohexanes
b-Organophosphates
I. Phosphate
II. Phosphonate
III. Phosphorothionate
c-Carbamates
Carbaryl, aldicarb
d-Pyrethrins & pyrethroides
I. Natural Pyrethrins
Pyrethrum extract
II. Synthetic pyrethroides
Allethrin, permethrin,
B-herbicides
or weedicides
I. Dinitro compounds
Dinitrophenol
II. Phenoxyacetic acid
2,4-D,2,4,5-T
III. Bipyridinium compounds
Paraquat, diquat
IV. Triazenes
Atrazine, propazine
C-Rodenticides
Zinc phosphate, flouroacetate
I. Inorganic agents
II. Dicoumarol derivatives
Warfarin
Red squill
III. Glycosides
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