How to observe and diagnose sheep diseases? These six methods you need to know
Inspection is the direct observation of the sheep's mental state and the various abnormal changes it presents. Healthy sheep generally compete for feed, move at the same speed, and react quickly; sick sheep often lag behind the flock, stop eating, stand still, or lie down.
Posture: healthy sheep have bright, spirited eyes and move lively and steadily; when sheep are sick they often show unsteady movement or are unwilling to walk, and some infectious diseases also present special postures, such as tetanus manifesting as stiff limbs, and sheep with coenurosis (brain tapeworm cysts) or sheep nasal bot fly turning in circles, and lameness.
Body condition: generally, in cases of acute anthrax, sheep bradsot (fast disease), sheep black disease, sheep sudden death disease, sheep enterotoxemia, etc., the sick sheep's body may still appear fat and strong; on the contrary, when generally suffering from chronic infectious diseases and parasitic diseases, sick sheep are mostly thin and weak.
Coat and skin: healthy sheep have a smooth coat that does not shed easily and has a glossy sheen; the coat of sick sheep is often rough, dull, brittle, and sheds easily, such as in sheep mange, which often shows coat loss and scabbing, thickening of the skin, and rubbing and scratching injuries. When examining the skin, in addition to noting its appearance, also note whether there is edema, inflammatory swelling, or trauma (parasitic diseases: edema appears under the jaw, on the chest, etc.).
Visible mucous membranes: in healthy sheep, the visible mucous membranes, such as the ocular conjunctiva, nasal cavity, oral cavity, vagina, and anus, are pink, moist, and smooth. If the mucous membranes become pale, it is a sign of anemia; if the mucous membranes are flushed, it is mostly due to elevated body temperature caused by febrile diseases; if the mucous membranes turn yellow, it indicates increased bilirubin in the blood, liver disease with bile duct obstruction, or hemolytic anemia, etc. For example, in sheep suffering from piroplasmosis, liver fluke, etc., the visible mucous membranes all show varying degrees of yellow staining; when the color of the mucous membranes is purplish red (also called cyanosis), it indicates increased reduced hemoglobin in the blood, a sign of severe hypoxia. This is commonly seen in respiratory difficulty diseases, toxic diseases, and the critical stage of certain diseases.
Examination of feeding and rumination: the quality of appetite directly reflects the health status of the sheep's whole body and digestive system. Loss of appetite indicates a serious condition; if it eats but does not dare to chew, the oral cavity and teeth should be checked for abnormalities. Healthy sheep usually have a moist muzzle, and rumination begins half an hour after feeding; each rumination lasts 30 minutes to 40 minutes, each bolus is chewed 50 times to 70 times, and there are 6 to 8 ruminations per day and night. A dry muzzle, and reduced or stopped rumination, are mostly due to high fever and severe inflammation of the forestomach and true stomach and intestines; in the early stage of febrile diseases, there is often increased thirst.