Clostridium botulinum is a spore (oval, sub terminal endospores) forming, gram positive organism and produces neurotoxins during their vegetative growth.
It has 7 antigenitically distinct types from A to G.
Farm animals are affected with toxin type B, C and D.
Source of infection
Preformed toxin (Forage botulism)
Contaminated feeds with toxin containing carrions(Carrion associated botulism)
Toxin production in wounds (Wound botulism)
Alimentary tract (Toxico infectious botulism)
Transmission
Ingestion of contaminated material or birds or blow flies are possible.
Spread of infection through injury.
2 of 3
Host affected:
Cattle and sheep are susceptible for type C and D while horses are susceptible for type B toxin.
Pigs, dogs and cats found to be resistant.
Human is also susceptible for bolutinum toxins.
Pathogenesis:
Organism→Botulism toxins (neurotoxin) → absorbed by the intestinal tract or the wound → traverse through the blood stream → peripheral cholinergic nerve terminals → neuromuscular junction→interfere the release of Ach→ leading to flaccid paralysis→Death due to respiratory paralysis.
Clinical findings:
Early muscle tremor,
progressive symmetrical weakness,
motor paralysis leading to recumbency.
Mydriasis
ptosis
walking (Limber neck).
3 of 3
weak tongue retraction
sensation and consciousness retained until death
In sheep, in early stage there is excitability, stiffness while walking and incoordination. The head may be held on one side or bobbed up and down while
Diagnosis:
Demonstration of toxin in serum or feed.
Demonstration of organisms in feed, intestinal contents or wounds
Treatment:
With type-specific antiserum and supportive treatment as fluid therapy and enteral feeding.
Control:
Avoidance of exposure by feed management and Vaccination.
Zoonotic implications:
Botulinum toxin is identified as a possible agent for bioterrorism.
The meat and milk from cattle that have botulism should not be used for human consumption.