Answer :
Final answer:
Blackhead disease is related to the symptoms of droopiness, darkening of the head, and diarrhea, and is caused by the protozoan Histomonas meleagridis. For severe dysentery, Entamoeba histolytica is the causative protozoan. The correct option is B.
Explanation:
The symptoms you are describing: droopiness, darkening of the head, and diarrhea, are associated with blackhead disease, which is also known as histomoniasis. This is a protozoan disease that affects poultry, particularly turkeys, and is caused by the protozoan Histomonas meleagridis.
Blackhead disease can also lead to lesions in the liver and cecal walls. In addition to the clinical symptoms, diagnosis is usually confirmed through necropsy and microscopic examination of the liver and ceca for the presence of the protozoa.
Regarding the other question, the protozoan that is known for causing severe dysentery is Entamoeba histolytica, which is the correct answer to the multiple-choice question.
