(1)Epidemiological characteristics The disease mainly occurs in 3 months of age, the most susceptible to infection within 15 to 45 days of age, and the morbidity and mortality rate is very high. 11 days of age of chicks rarely occurs, and adult chickens are mostly carriers of worms.
The disease can occur all year round, but it is more frequent in spring and summer when there is more rain and the temperature is 22-30℃. In broiler pullets, the onset of the disease is less pronounced in the season than in laying hens due to the warm and relatively humid microclimate in the coop. The main route of infection is the digestive tract. However, crowding, malnutrition, poor hygiene, humidity, and imbalance in brooding temperature are causative factors for the onset of the disease.
(2) The main symptoms and autopsy changes The sick chickens are afraid of the cold and crowded together, the hair is messy wings hanging, closed eyes dozing. Frequent dysentery, discharge of bloody thin feces or blood. Anemia, pale crown and beard, crop full of liquid, late movement disorder, collapse and spasm death. 3 months of age and above the young chickens are mostly chronic, not necessarily bloody feces, but progressive wasting, stagnation, later paralysis, exhaustion and death.
The mucous membranes and crowns of dead chickens are pale or blue, and the feathers around the cloaca are contaminated with liquid feces. The main lesion in the cecum, the cecum can be seen several times swollen, brown-red or dark red, the texture is firmer than normal, cut open the visible blood clot, or contains a yellowish-white tofu dregs-like, mixed with blood necrotic material. If the time is a little longer, there is an embolus in the cecum made of clots, necrotic material, sticky exudate coagulation, blocking the intestinal lumen. In chronic cases, the lesions are mostly in the anterior and middle portions of the small intestine, especially the duodenum is significantly enlarged. Inflammation and thickening of the intestinal wall, cut open the intestinal mucosa with small hemorrhagic areas, viscous exudate, often mixed with blood clots.
(3) Prevention and control The prevention of coccidia is mainly to strengthen the hygiene management, to keep the house dry, regular cleaning of feces, and all kinds of disinfection according to the requirements of integrated epidemic prevention measures. In order to reduce the infection of coccidia, it is best to use cage rearing or online flat rearing.
There are many types of anti-coccidial drugs, which should be chosen according to the specific situation. At the same time, pay attention to the drug resistance of the coccidia, there should be a plan to change the drug. The following is a list of commonly used species:
Ball diarrhea spirit: the amount of treatment is 25 grams per 100 kilograms of feed, used for 3 to 5 days, the amount of prevention is reduced by half, continuous use. The dosage and usage of Nicarbazin, Aminopyralid, and Kebodol are the same as that of bulbous dysentery.
Chlorphenylguanidine: the therapeutic dosage is 3 grams per 100 kilograms of feed, and the preventive dosage is reduced by half, and it is used continuously for 5 to 7 weeks. Because this product will make the meat with a strange odor, so broiler chickens should be discontinued 7 to 10 days before the market.
Salicylic acid: from 10 days of age before the start, every 100 kg of feed plus 5-7 grams of this product, mixed feeding. 7 to 10 days for a course of treatment, the interval of 5 days and then use.
Eversanone: the therapeutic amount is 0.4 grams per 100 kilograms of feed added to the mix, the preventive amount is reduced by half, used for 1 to 2 weeks.
Compound trichlorfon: the therapeutic amount is 20 grams per 100 kilograms of feed, mixed feeding.
Henamycin: 75 grams per 100 kilograms of feed, mixed feeding, preventive amount of 2/3 of the amount of treatment.
Additionally, new anti-coccidial drugs such as capreomycin, maduramycin, chlorzine phenyl ethyl cyanide are also widely used in the clinic. Others can also be used to prevent and control with gentamycin, broad bug spirit, chicken treasure-20, three words of coccidia powder and other mixed feeding or drinking water, and can also be used to prevent and control with penicillin intramuscular injection and other methods.