Detailed Explanation of Disease Diagnosis by Observing Colors in Cattle and Sheep and Prevention and Treatment Techniques
In long-term livestock and veterinary production practice, we have summarized nearly thirty years of experience and relevant reports. By observing the colors of cattle and sheep, diseases can be diagnosed quite accurately, and at the same time, effective new techniques can be adopted for prevention and treatment, achieving good therapeutic results.
1 "Cylinder color" disease diagnosis
1.1 Cattle and sheep "red eye disease"
The pathogen of this disease is Haemophilus or conjunctival Rickettsia, and both cattle and sheep can be infected.
1.1.1 Symptoms
Both eyes are affected simultaneously, eyelids are swollen, photophobia and tearing: conjunctivitis, diffuse flushing; corneal ulcer, no systemic symptoms, often occurring in large herds, showing endemic prevalence.
1.1.2 Treatment
Flush the affected eye with 2% boric acid aqueous solution, then apply chloramphenicol eye drops, 3-5 drops per eye; boil water with cypress branches and alum, and wash the eyes after it cools.
1.1.3 Prevention
After a few cases occur, immediately isolate and treat; maintain good barn hygiene and eliminate mosquitoes and flies.
1.2 Cattle "red nose disease"
Bovine infectious rhinotracheitis has 5 types, namely respiratory type, genital type, conjunctival type, abortion type and encephalitis type. The pathogen is bovine herpesvirus type I, among which the respiratory type is also called red nose disease, and it accounts for the largest proportion of cases among the 5 types.
1.2.1 Symptoms
Sudden onset, depression, reduced feed intake, rumination stops, fever rising above 40°C. Rapid breathing, large amounts of purulent nasal discharge, ulcers on the nasal mucosa, highly congested, fiery red in appearance, hence the name "red nose disease."
1.2.2 Treatment
There is no specific therapeutic drug; prevention is emphasized. To prevent secondary infection, antibacterial drugs may be used; to relieve symptoms, symptomatic treatment may be given.
1.2.3 Prevention
Vaccination with attenuated vaccine has a good preventive effect. Because maternal antibodies in colostrum can persist for 4 months, calves should begin immunization at 5 months of age.
1.3 Sheep "red hoof disease"
Sheep red hoof disease is a hereditary disease, mainly occurring in Scottish Blackface lambs and their first-generation crosses.
1.3.1 Symptoms
Severe lameness, hoof shells easily fall off, and after falling off they expose bright red hoof laminae, hence the name red hoof disease; some affected sheep also develop corneal ulcers.
1.3.2 Treatment
No specific treatment method.
1.3.3 Prevention
Because there is still no sheep breed in China prone to this disease, keeping foreign sheep breeds prone to this disease out of the country is the best preventive method.
2 "Blue" disease diagnosis
2.1 Infectious blue eye disease in cattle and sheep
2.1.1 Symptoms
Both eyes are affected, the cornea becomes cloudy and grayish blue, the blindness rate in cattle is 3.1%, and the blindness rate in sheep is 15.3%.
2.1.2 Treatment
Gentamicin sulfate 200,000 IU, dexamethasone 20 mg, atropine 200 mg, ribavirin 20 mg, distilled water 20 mL, dissolved and prepared as eye drops. Apply eye drops 6 times daily, 3-5 drops per eye each time; after symptoms lessen, apply 4 times daily, 2-3 drops each time. For those with corneal ulcer, use vitamin B2 instead of dexamethasone and prepare as eye drops, with the same usage as before.
2.2 Bluetongue disease in cattle and sheep
2.2.1 Bovine bluetongue disease
This disease is caused by bovine bluetongue virus, with Culicoides midges as the main transmission vector.
2.2.1.1 Symptoms
At the beginning of the disease, fever rises to 40.5-41.5°C, persisting for 2-3 d, the tongue swells and turns bluish purple, oral mucosa swells and ulcerates: large amounts of salivation, grazing and rumination are slow and cautious.
2.2.1.2 Treatment
Flush the oral cavity with 0.1% potassium permanganate solution; apply iodine glycerin or gentian violet to oral ulcers; feed fresh, tender and soft green grass.
2.2.1.3 Prevention
In summer, thoroughly eliminate blood-sucking flying insects, especially Culicoides midges; fill in low-lying areas with standing water; clear weeds from the ground; disinfect barns with 1%-2% sodium hydroxide solution.
2.2.2 Sheep bluetongue disease
The pathogen and symptoms of sheep bluetongue disease are basically the same as those of bovine bluetongue disease, but sheep additionally have symptoms of gastroenteritis, frequent diarrhea, and blood in the feces. In addition, when sheep suffer from this disease, pregnant sheep can transmit it to the fetus through the placenta, and rams can transmit it to ewes through semen. In addition to referring to the treatment methods for cattle, the treatment of this disease also requires treating digestive tract inflammation, such as gentamicin sulfate 1.5 mg/kg, intramuscular injection, twice daily. Prevention is the same as for the bovine disease.
3 "Black" disease diagnosis
Sheep black disease, also known as infectious necrotic hepatitis, is caused by Clostridium novyi type B.
3.1 Symptoms
Sheep, especially obese sheep aged 2-4 months, are more commonly affected, with sudden onset, rapid death, and very fast spread. A small number of subacute cases show depression, complete loss of appetite, cessation of rumination: difficult breathing, body temperature rising to 41°C, death in 1-2 d. After death, due to severe congestion of superficial blood vessels, the sheep's skin appears black.
3.2 Treatment
Use anti-Clostridium novyi serum, 2-4 mL per sheep, intramuscular injection.
3.3 Prevention
3.3.1 Pentavalent vaccine (sheep black disease, sheep bradsot, sheep struck, sheep enterotoxemia, lamb dysentery), regardless of size, 5 mL per sheep, subcutaneous or intramuscular injection, once every year.
3.3.2 Dead sheep from disease should be burned or deeply buried.
3.3.3 Sheep sheds should be disinfected with 20% bleaching powder solution.
3.3.4 Do not graze near low-lying water areas.