Clinical signs vary from animal to animal and the severity of infection. Infections can be categorized into three classes:
- 1. Peracute
It is common in cattle and sheep and is characterized by fever, congestion of mucosa, dyspnea, muscle tremor, and convulsions followed by the death of the animal. The course of the disease is the shortest of other categories i.e., only 2 hours. Death is usually accompanied by bloody discharges from the animal’s natural openings like nostrils, mouth, anus, and vulva.
- 2. Acute
The disease course for the acute form of anthrax is about 2 days. The common symptoms in the case of cattle and sheep are fever, an interval of excitement, followed by depression, troubled breathing, cardiac distress, seizures, and at last death. ruminal stasis, reduced milk production, yellow milk or blood stains in milk, abortion in pregnant cows, diarrhea, and edema in ventral areas of the neck, shoulder, and thorax have also been observed.
- 3. Chronic
The chronic form of anthrax is common in swine though it can also occur in cattle, horses, cats, and dogs. Usual manifestations include extensive subcutaneous, localized, edematous swelling in anterior areas of the neck, shoulder, and thorax.