How to prevent and treat sheep streptococcosis? All the practical methods are here
Sheep streptococcosis is a disease that seriously harms goats and sheep. It is an acute febrile infectious disease caused by hemolytic streptococcus, occurring mostly in the cold seasons of winter and spring (from November each year to April of the following year). It is mainly transmitted through the digestive tract and respiratory tract, and its clinical features are mainly swelling of the submandibular lymph nodes and throat. Sheep are the most susceptible, and goats are also very easily infected. It mostly shows endemic prevalence in the winter and spring seasons when sheep are in relatively weak body condition, and in old epidemic areas it is generally sporadic. The clinical features are fever, swelling of the lower jaw and throat, enlargement of the gallbladder, and fibrinous pneumonia.
Symptoms of sheep streptococcosis
At the beginning of the disease, the sheep is listless, has reduced appetite or stops eating, stops ruminating, walks unsteadily, has conjunctival congestion, tears, later purulent discharge, serous nasal discharge from the nasal cavity that later becomes purulent, drooling, body temperature rising above 41°C, swelling of the throat and tongue, soft feces with mucus or blood, abortion in pregnant ewes, and some sick sheep have swelling of the eyelids, lips, cheeks, and udder, and groan, grind their teeth, and twitch before death. Acute cases have difficulty breathing and die within 24 hours. Under normal circumstances, death occurs in 2 to 3 days.
Diagnosis of sheep streptococcosis
A preliminary diagnosis can be made based on clinical symptoms and necropsy changes combined with epidemiology. Confirmation can be made through laboratory tests. Microscopic examination shows that this bacterium is mostly diplococcal, occurring in chains or singly, with a capsule around it, and is Gram-positive. Smears are made from the liver, kidney, and lung tissues of dead sheep, stained by Gram stain, and examined under the microscope. Gram-positive cocci that are diplococcal and have capsules can be seen, occasionally with short chains of 4 to 6, and individual single cocci are occasionally seen. There is a capsule around them, and Gram staining is positive. The diseased material is aseptically inoculated on a blood agar plate and cultured for 24 hours. Fine, grayish-white, glossy, transparent, moist, viscous colonies resembling dew drops can be seen, with an obvious β hemolytic zone around the colonies. The culture is then smeared, stained, and examined under the microscope, and mostly long-chain Gram-positive cocci can be seen. 1 ml of a 24-hour culture in Martin broth is injected subcutaneously or intravenously into rabbits, and most die in 24 to 28 hours, and bacteria can be isolated from their heart blood and various organs.
Prevention and treatment of sheep streptococcosis
1. Improve grazing management conditions, keep warm and prevent wind, prevent freezing, prevent crowding, and prevent the introduction of pathogens.
2. Regularly eliminate internal and external parasites of sheep.
3. Do a good job in disinfecting sheep pens, sites, and utensils. Before the beginning of winter, use streptococcus aluminum hydroxide formaldehyde vaccine for preventive injection. Regardless of size, all sheep are injected subcutaneously with 3 ml, and lambs within 3 months of age are immunized again after 14 to 21 days.
4. After the disease occurs, sick sheep and suspected sheep should be isolated and treated separately. Sites, utensils, and so on should be strictly disinfected with 10% lime milk or 3% Lysol. Sheep manure and contaminated materials should be piled up for fermentation, and dead sheep should undergo harmless disposal.
5. Each sick sheep is injected intramuscularly with 300,000 to 600,000 international units of penicillin once a day for 3 consecutive days. Intramuscular injection of 10 ml of 10% sulfathiazole once a day for 3 consecutive days. Sulfadiazine or chlorobenzenesulfonamide can also be given orally at 4 to 8 grams twice a day for 3 consecutive days.
6. For those with high fever, each is injected intramuscularly with 3 ml of 30% analgin. For severe cases with complete loss of appetite, give cardiac stimulants and fluid replacement: 500 ml of 5% glucose saline, 5 ml of caffeine sodium benzoate, 5 ml of vitamin C, and 10 ml of dexamethasone by intravenous drip twice a day for 3 consecutive days.
7. Strengthen feeding management, do a good job in fattening and maintaining body condition, and keep warm, prevent wind, prevent freezing, and prevent crowding. Regularly eliminate internal and external parasites of sheep. Do a good job in disinfecting sheep pens, sites, and utensils. Before the beginning of winter, use streptococcus aluminum hydroxide formaldehyde vaccine for preventive injection. Regardless of size, all sheep are injected subcutaneously with 3 ml, and lambs within 3 months of age are immunized again after 14 to 21 days. In epidemic areas, injecting each healthy sheep with anti-sheep streptococcus serum or antibiotics such as penicillin has a certain effect.