Sheep gastrointestinal parasitic disease is a common disease in sheep, which belongs to the hidden infectious disease and chronic wasting disease. When the sheep are infected by parasites, the parasites will compete with the body for nutrients, and even produce toxic substances, resulting in malnutrition in the sheep, slow weight growth, and reduced production performance; at the same time, due to parasitic diseases in sheep, the body's physique declines and immunity declines. The types of gastrointestinal parasites in sheep breeding mainly include nematodes, coccidiosis, tapeworms, trematodes, etc., of which coccidiosis and nematodes have the highest probability of infection in sheep breeding. Sheep breeding in the spring and other high temperature and high humidity seasons of gastrointestinal parasitic diseases are high probability, mainly due to the high humidity environment is suitable for the growth and development of parasites, while the winter temperature is cold, not suitable for the development of most parasitic eggs, the incidence is relatively low. Sheep digestive tract parasitic diseases have a high probability of occurrence in lamb breeding, and the disease problems usually caused by them are also more serious, mainly due to the lack of sound immune function and poor disease resistance in the lamb stage.
First, the harm of parasites in the digestive tract of sheep
1.1 After sheep infected with digestive tract parasitic diseases, they engulf histiocytes and trigger histiocytic reactions Sheep digestive tract infection will cause digestive system diseases, and parasites will absorb a large amount of nutrients in the body, so that some tissues will be inflamed and necrotic. At the same time, the parasite infects the digestive tract of the sheep after its own toxicity will bring irritation to the sheep's body, so that its original blood and cell function is lost, causing mechanical damage to the sheep, making the surrounding tissues compressed, and the blood vessels of the sheep are damaged with other tissues, causing various complications.
1.2 After a sheep is infected with a parasitic disease of the digestive tract, the parasites in their bodies will rob and absorb nutrients, resulting in slow growth, emaciation, and decreased resistance of the sheep. If sheep are malnourished for a long time, their livestock production will decline, which will affect the economic interests of farmers.
1.3 After sheep are infected with parasitic diseases, the skin tissues or mucous membranes in their bodies will be damaged to varying degrees, facilitating the spread of other pathogens. Coupled with the fact that parasites compete for nutrients after infection and reduce immune function, it will make sick sheep more susceptible to other diseases.
Second, the type of parasite in the digestive tract of sheep
There are many parasitic diseases in the digestive tract of sheep, and at present, the three major intestinal parasites such as nematodes, tapeworms and trematodes are the most harmful in the healthy breeding of sheep.
2.1 Tapeworm disease
The main infections of taeniasis in the sheep digestive tract include Taenia extended, Tapeworm ambulatory, Taenia acanoidoides aeolus, and Taenia benetii. It is widely distributed in China, often endemic, and the most serious harm to lambs, which not only affects their growth and development, but also can cause death. Tapeworms of each genus differ only in pathogenic morphology, with roughly the same life history and other aspects, and mostly mixed infections.
After the sheep digestive tract is parasitized by tapeworms, it shows loss of appetite and decreased intake, increased water intake, poor mental health, and slow growth. As the disease progresses, lambs develop diarrhea and diarrhea, exhaustion, mature tapeworm segments appear in the stool, and some also have neurological symptoms such as convulsions, spasms or whirlwinds. By the end of the period, the sick sheep will lie down, tilt their heads back, often do chewy movements, have many white foam around the corners of their mouths, and eventually die of exhaustion. When the parasite number is high, it can also cause intestinal obstruction, intussusception, intestinal volvulus, and intestinal rupture.
2.2 Nematode disease
In China's sheep breeding, the main ones are the following nematode diseases: twisted blood spear nematode, Marshall genus, Oster genus, hairy round genus and slender neck genus, serpentine hairy worm, back mouth nematode.
In sheep breeding, the appearance of gastrointestinal nematode disease infection mainly leads to digestive disorders, anemia, emaciation and diarrhea diarrhea in sheep, the production performance and health of the body of the sheep are significantly reduced, while the conjunctiva of the diseased sheep appears pallor lesions, jaw and lower abdomen appear edema, some sheep only appear constipation, and sheep with serious diseases will die.
2.3 Predominant trematodiasis
There are many kinds of flukes commonly seen in veterinary clinics, such as liver flake trematodes, ginger trematodes, Japanese schistosomiasis and Chinese mycodchidism, among which liver flakes flukes are the most harmful to sheep. Liver flakes flukes are mainly parasitic in the liver and bile ducts in sheep, causing different degrees of hepatitis and cholangitis. The liver of the sheep is enlarged, the semi-dull area of the percussion hepatic area is enlarged, and the tenderness is obvious. Some also have edema of the eyelids, chest, abdomen and jaw, alternating constipation and diarrhea, and in severe cases, death within a few days, especially sheep, has a high mortality rate.
2. 4 Common species of coccidiosis infection in sheep farming
Goat coccidiosis occurs more often in spring, autumn and summer, especially in the high temperature and humidity season, which is the high incidence of coccidiosis. Coccidioides infection in sheep breeding is mainly coccidiosis parasitism of the Emmel species, which is more common in sheep and goat breeding, mainly leading to diarrhea and diarrhea, anemia, emaciation and growth retardation in sick sheep, and serious conditions will lead to the death of sheep, and the probability of infection and death in lamb breeding is relatively high.
Although sheep of all ages can become infected with coccidioidal oocysts, adult sheep have no obvious clinical symptoms after the onset of the disease. Lambs aged 1 to 3 months are not only prone to infection due to oral ingestion of egg sacs, but also mild symptoms are manifested by soft stool, decreased appetite, and reduced feeding intake. Severely ill sheep have a sudden increase in body temperature at the beginning of the disease, and then begin to fall, with sharp diarrhea, with obvious blood-colored mucus in the feces, and a foul odor, with a large number of coccidiosis egg sacs.
3. Prevention and control measures
3.1 Strengthen breeding management
In the process of sheep rearing, adequate feeding and full price can enhance the quality of sheep and enhance their disease resistance. Environmental hygiene should be done well, the sheep house should be clean and dry, strictly prevent feces from contaminating feed and drinking water, regularly clean the pen, and thoroughly and strictly disinfect. Reasonably control the feeding density to avoid crowding in the house. Avoid grazing and resting in low wetlands and allowing sheep to drink flowing clean water, which is a prerequisite for preventing sheep parasitic diseases. Regular vaccination of petitary diseases of the digestive tract of sheep can be prevented or even eliminated by regular vaccination. For lambs with poor immunity and weak constitution, if they are infected with digestive tract parasites, it will have a more serious impact on their growth and development than adult sheep, so they should be given special attention after the birth of lambs, and regularly vaccinated lambs to improve their antiviral ability and reduce their infection rate.
3.2 Regular deworming
Nematodes are a digestive tract parasitic disease that sheep are more susceptible to infection with, and farmers can use propithiimidazole or mebendazole for deworming. According to the standard of 15 mg / kg · bw oral mebendazole, propythioniazole prepared as a suspension, or according to 8 mg / kg · bw oral levamisole, or subcutaneous injection of broad-spectrum anti-insecticidal avermectin, or combined sheep body weight according to 0.1 mg / kg · bw oral tetrachloroethylene.
Trematode is also a digestive tract parasitic disease that sheep are more susceptible to infection, and for sick sheep, nitroglophenol is taken orally according to 4mg/kg·bw, twice a year. If the degree of infection in the sick sheep is more serious, it can be injected subcutaneously with compound long-acting propiosulfoxide injection, and the standard of use is 0.2mL/kg according to the weight of the sick sheep, 1 time/day, for 3 days.
Tapeworm tapeworm is also a kind of digestive tract parasitic disease that sheep are more susceptible to infection, farmers can combine the weight of the sheep with 100mg/kg to irrigate thiodichlorophenol when deworming the sick sheep infected with tapeworm, and the thiodichlorophenol should be mixed with water when filling, and the drug should be used after dissolution. Or the weight of the combined sheep is fed niclosamide according to 50~ 75mg/kg; and the weight of the combined sheep can be fed with 1% copper sulfate solution according to the standard of 2mL/kg, which can achieve a more ideal deworming effect. Of course, if you want to prevent tapeworms, you can combine the weight of the sheep with 15 mg/kg of propylene thiazole.
Sheep coccidiosis adds amphelane or halomycin to the feed, adds 145 mg or 0.33 to 1.00 mg per kilogram of body weight, and uses it continuously for 2 to 3 weeks, which has a better effect on the prevention of coccidiosis or early treatment. The addition of sulfamethoxypyrimidine to the feed for 5 days at 50 to 100 mg·d-1 per kilogram of body weight is more effective in acute cases. Sulfamethoxypyrimidine and synergists can also be used together in a ratio of 5:1, and given to sick sheep for internal use at 0.1 g·d-1 per kilogram of body weight, continuous use for 3 days, the treatment effect is better.