3. Tetanus
•Tetanus is caused by the neurotoxin produced by
Clostridium tetani .
• Clostridium tetani is found in soil and intestinal
tracts and usually introduced into tissues through
deep puncture wounds.
4. Susceptibility
•Almost all mammals are susceptible.
•Horses and lambs seem to be the most sensitive of
all species.
•Dogs and cats are relatively more resistant than any
other domestic or laboratory mammal.
5. Pathogenesis of Tetanus in Animals
•C tetani, an anaerobe with terminal, spherical
spores, is found in soil, .
•It is introduced into the tissues through wounds,
particularly deep puncture wounds, that provide a
suitable anaerobic environment.
6. In Cattle
•In cattle introduction into the genital tract at the
time of parturition .
•In idiopathic tetanus it would appear that the
neurotoxin is produced in the rumen.
7.
8. The effect of the toxin
•The toxin causes spasmodic, tonic contractions of the
voluntary muscles by interfering with the release of
inhibitory neurotransmitters from presynaptic nerve
endings.
•The toxin causes a generalized muscular spastic
paralysis.
9. 1-Toxin enters the axons of the
nearest motor nerves at the
neuromuscular end plate and
migrates to the neuronal cell body
within the spinal cord .
2-Toxin ascends bilaterally until it
reaches the brain .
10. Why the animal die?
•The spasms may be severe enough to cause bone
fractures.
• Spasms affecting the larynx, diaphragm, and
intercostal muscles lead to respiratory failure.
• Involvement of the autonomic nervous system
results in cardiac arrhythmias, tachycardia, .
•Tympany in ruminant can cause death
12. Clinical Findings in Equines
•Localized stiffness, often involving the masseter
muscles and muscles of the neck, the hind limbs, and
the region of the infected wound, is seen first.
•General stiffness becomes pronounced ~1 day later,
and tonic spasms and hyperesthesia become
evident.
13. Clinical Findings of Tetanus in
Animals
• Lockjaw:
• Spasms of head muscles cause difficulty in prehension and
mastication of food, .
• The ears are erect, the tail stiff and extended,
• The anterior nares dilated, and the third eyelid prolapsed.
• Walking, turning, and backing are difficult.
• Spasms of the neck and back muscles cause extension of the
head and neck.
• Sweating is common.
23. Localized tetanus is the more common form of tetanus that
occurs in pets. Affected dogs develop muscle rigidity (stiffness)
in the limb or muscles closest to the wound. In addition to
muscle rigidity, muscle tremors may also be seen. Localized
tetanus can progress to generalized tetanus with time
Types of tetanus
24. Diagnosis of Tetanus in Animals
•The clinical signs and history of recent trauma are
usually adequate for a clinical diagnosis of tetanus.
•Toxin presence confirmed by PCR assay of wound
tissue
26. Differential Diagnosis
in cattle
1-Clinical hypomagnesaemia :
•Accompanied by tetany and convulsions, but there is
no prolapse of the third eyelid or ruminal tympany.
• Low blood calcium and magnesium levels .
28. Differential Diagnosis
in cattle
3-Lead poisoning :
May also show similar clinical signs, but elevated
blood and kidney/liver lead values are diagnostic.
4- Three day sicknes
42. Clinical signs in cattle
االبقار فى االساسية االعراض
•Stiffness and reluctance to move are normally the
first signs
•Twitching and tremors of the muscles
•Lockjaw
•Prominent protruding third eyelid
•Unsteady gait with stiff held out tail
•Bloat.
44. Line of Treatment
•Wound care( if present)
•Large doses of antibiotics, usually penicillin.
•Tetanus antitoxin injected usually intravenously and
intramuscularly.
•Sedative & Muscle relaxant
•Supportive treatment
45. Objective of Treatment
العالج من الهدف
•Cattle appear to respond better to treatment than
•horses and sheep.
•Three objectives:
1- Elimination of Cl. Tetani.
2- Neutralization of unfixed neurotoxin.
3- Induction and maintenance of muscle relaxation
48. 3- Tetanus Antitoxin
•Tetanus Antitoxin injected usually intravenously and
intramuscularly.
•For treatment, administer:
• 10,000 to 50,000 units to horses and cattle,
• 3,000 to 15,000 units to sheep and swine.
49. Example
Tetanus Antitoxin, Equine Origin is for
use in horses, cattle, sheep, goats and
swine for the prevention and
treatment of tetanus.
It is recommended for use whenever
a non-immunized animal,
51. 4-Sedative & Muscle relaxant
•Xylazine:
•is an analogue of clonidine and an agonist at the α2
class of adrenergic receptor.
• It is used for sedation, anesthesia, muscle
relaxation, and analgesia in animals such as horses,
cattle .
52. Dose of Xylazine
Intravenous (IV):
The dose of 0.12 mg/kg is effective
for most ruminants.
Intramuscular:
Cattle: 0.3 mg /Kg
Horse: 0. 6 mg /Kg
Sheep: 1 mg/Kg
53. 2-Chlorpromazine
Chlorpromazine (0.4mg/kg body weight intravenously.
1.0mg/kg body weight intramuscularly) three to four times
daily.
0r:
Acetyl promazine (0.05mg/kg):
body weight), administered twice daily for eight to ten
days or until the severe clinical signs have disappeared.
56. Keep in Dark place
•Animals should be kept in dark quiet surroundings
with ample bedding and sufficient space to avoid
injuring themselves if convulsions occur.
57. Control of Tetanus in Animals
الكزاز بمرض االصابة من الوقاية طرق
58. 1- Toxoid Vaccination
السموم مضاد تطعيم
•Mares should be vaccinated during the last 6
weeks of pregnancy, and foals at 5–8 weeks of
age.
•Two injections given approximately four to six
weeks apart followed by a booster at one year
and further boosters annually.
59. 2-Tetanus Antitoxin
الكزاز سم بمضاد األمهار تطعيم
• In high-risk areas, foals may be administered tetanus
antitoxin immediately after birth and every 2–3
weeks until they are 3 months old, at which time
they can be administered toxoid.
•It give immediate passive immunity lasting about 7
to 14 days.
• 1500 units administered subcutaneously or
intramuscularly is the recommended dose for
prevention.
