Clinical signs

CLINICAL SIGNS

  • Myasthenia.
  • Inability to swallow.
  • Progressive muscle paralysis with muscle weakness first in the hindquarters and then progressing to the forequarters, then the head and neck become involved.
  • Birds
    • signs start with the progressive paralysis of the neck, legs and wings. Birds gasp for air and sometimes pass greenish diarrhoea. Usually they die in coma within 24 - 48 hours due to respiratory and circulatory failure.
  • Dogs
    • show general weakness which is followed by an ascending paresis and paralysis with cranial nerve involvement (facial paralysis may be present). Remain alert and responsive, wag tail and move head even when paralyzed. Mydriasis with slow pupillary reflexes, decreased palpebral reflexes. May have secondary dehydration and/or urinary tract infections as well as secondary respiratory infections.
  • Cattle
    • Inability or decreased ability to stand. Sternal and sometimes subsequent lateral recumbency. Often down with head down or turned to the side, like a cow with milk fever, may die in sternal recumbency. Rumen motility decreased or absent.
    • Hypersalivation, Paralysis of muscles of mastication and cannot resist forced opening of the mouth. Tongue may have normal tone, but often exhibits varying degrees of flaccid paralysis. This is most apparent after pulling the tongue out of the mouth repeatedly.
    • Dry faeces with large amount of mucus. Slow pupillary response to light. Death occurs without agonal respiratory gasps. Deaths in a herd may occur in one to several cows per day every day or every few days. Hyperglycemia may be noted.
  • Foals and Horses
    • Progressive symmetrical muscle paralysis, with stilted gait. Muscle tremors, inability to remain standing for longer than 4 - 5 minutes, drop to sternum.
    • In foals, milk runs out of their mouths as they attempt to suckle. Difficulty in swallowing water; tongue and pharyngeal paralysis. Loss of tongue tone is often an early clinical sign in adult horses.
    • Reduced intestinal peristalsis.
    • Constipation.
    • Frequent attempts to urinate with voiding of only a few ml of urine.
    • Mydriasis.
    • Tachycardia. Respiratory arrest, generally after a period of lateral recumbency, with the neck extended.
Last modified: Sunday, 30 October 2011, 10:34 AM