TETANUS. 



Synonyms. Definition : infectious disease, due to bacillus, and shown by 

 tonic spasms of groups of voluntary muscles. Animals susceptible : warm- 

 blooded animals — dog and chickens least : § ds. solipeds, 1th cattle. Pa- 

 thology and Causes : Bacillus tetani : 4 to 5m by 0.2 to 0.3^1, often enlarged 

 by spore at one end ; anaerobic, liquefying, tardily motile, until spore forms, 

 grows in ordinary, alkaline media under hydrogen, death point 6o° to 65 

 C. (140 to 149 F. ), for spores 8o° C. (176 F. ), for an hour, dried it lives 

 for years, in putrid matter 2^ months, stains easily, saprophytic in garden 

 mould, in ingesta of man and horse, abundant in tropics ; infection local, 

 killed by oxygen in blood, toxins tetanize : tetanin, spasmotoxin, toxalbu- 

 men, diastase ; spasms first local near wound, then abruptly general, intra- 

 venously causes general spasms first, theory of fermentation in blood ; 

 changes in nerve cells, neuroglia, ependyma, peripheral nerves : muscles 

 soft, pallid, red, ruptured fibres, ecchymosis ; rigor mortis early, marked : 

 sarco-lactic acid. Accessory causes : traumas and their causes, parturition, 

 umbilical infection, alimentary. General symptoms : incubation 3 to 15 

 days, minimum 6 hours ; tonic contraction of muscle groups of locomotor 

 system beginning near infection wound, — trismus, orthrotonos, opisthoto- 

 nos, emprosthotonos, pleurosthotonos, ocular muscles ; costive, difficult uri- 

 nation, hyperesthesia, irritability, perspiration, hyperthermia, mastication, 

 deglutition, sucking : Symptoms in horse : neck raised concave above, nose 

 elevated, nostrils wide, eyes sunken, haw protruded, ears rigid, pricked, 

 facial muscles rigid, prominent, mouth drawn back, muscles of back hard, 

 tail elevated, trembles, limbs extended outward, stiff, stilty, jaws clenched 

 or open slightly, stands : Symptoms in cattle ; sheep and goat ; swine ; dogs ; 

 birds : Course : violent cases with short incubation are rapid and fatal ; mild 

 ones with prolonged incubation hopeful ; cattle slow, sheep, goats and dogs 

 acute. Mortality : sheep and pigs 100 per cent. ; horses 75 to 85 ; cows 70 

 to 80 ; lambs very fatal. Death from asphyxia, hyperpyrexia, or exhaus- 

 tion. Lesions : trauma, often healed ; congested nerves, gray horns of my- 

 elon, increase of cells and granules in nervous matter of cord, corpus stria- 

 tum, cerebellum ; blood extravasations at torn muscle fibres, intestinal and 

 cystic congestion : Diagnosis : from strychnia poisoning by slow advance, 

 and persistence of spasm ; from rabies by absence of bite, the continuous 

 masseteric spasms, by absence of resentment, mischief, hallucinations or de- 

 praved appetite ; from rheumatism by the persistent trismus, hyperesthesia 

 and excitability ; from meningitis by the trismus, perfect mentality, ab- 

 sence of clonic spasm ; from tetany by shorter and less perfect remissions, 

 failure to develop under nerve pressure, or improve under thyroid extract ; 

 from laminitis by the absence of high early hyperthermia, heat and tender- 

 ness of the feet, and advance of hind legs under the body. Treatment : 

 best in slight cases, after long incubation, with slow progress ; antispas- 

 modics ; rest, darkness, absolute quiet, no litter, nor visitors, slings, sloppy 



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