but acute outbreaks can occur within two days of infection. In some cases, birds die within a few hours of showing the first signs, which vary depending on the form of the disease. The respiratory form is characterized by gasping, coughing and sneezing, while in the septicaemic form there is diarrhea with wet grey, yellow, or green droppings. In the localized form, the signs are lameness and swelling of legs or wing joints.
In acute cases, the head and comb change colour to dark red or purple. If the infection is localized in the region of the ears, a twisted neck( torticolis) can sometimes be observed. In chronic cases, the comb is usually pale, with swellings around the eyes and a discharge from the beak or nostril. Fowl Cholera is common everywhere among free-range village flocks, because they are comprised of different species and are in continuous contact with wild birds.
( 9) Pullorum( Bacillary White Diarrhea) This is an egg-transmitted disease( caused by Salmonella pullorum) that spreads during incubation or just after hatching. White diarrhea can be seen from three days to several weeks of age. The chicks refuse to eat, keep their heads tucked in and their wings hanging down. They huddle together and make a peeping sound. Mortality in the acute form ranges from 20 to 80 percent, and in the chronic form is around five percent. In the chronic form, the signs are a marked swelling of the hock joints, poor feather development, lack of appetite and depression.
( 10) Fowl Typhoid Fowl typhoid is caused by Salmonella gallinarum, and commonly affects adult fowls. When it occurs in young birds, the signs are similar to those of S. pullorum. The incubation period is four to five days, and two days later the birds become depressed and anorexic. The colour of the comb and wattles becomes dark red; the droppings become yellow and the birds close their eyes and keep their heads down. Usually the affected chickens die within three to six days. Pullorum and fowl typhoid complex are both prevalent under free-range conditions.
( 11) Avian Salmonellosis( Paratyphoid) Salmonella infections may affect all domestic poultry, although adult birds often do not show any symptoms. Salmonella bacteria may also contaminate hatching eggs, which results in diarrhea, depression and death in young chicks. Paratyphoid is highly infectious and can be transmitted by
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