Infectious Bronchitis (I.B.)
Causative Agent – Single stranded RNA virus from the family of coronaviridae.
SIGNS
The characteristic respiratory signs in chicks are gasping, coughing, sneezing tracheal rales and nasal discharges.
Wet eyes may be present occasionally along with swollen sinuses.
Huddlling under heat source.
Feed consumption reduces significantly.
ADULTS
Nasal discharges are absent.
In layers – decline in egg production in addition to respiratory signs is seen.
Poor shell, shell less eggs (Fig-12.1) and misshapen eggs during outbreak is a common feature. (Fig-12.2)
Severe decline in setting eggs and highly reduced hatchability.
Inferior quality of eggs with watery albumin, (Fig-12.3)
In broilers-depression, ruffled feathers,
Wet droppings and nephrosis is seen (Fig-12.4) apart from respiratory signs.
LESIONS
Catarrhal or caseous exudates in trachea, nasal passage and sinuses.
Airsacs cloudy, sometimes with yellow caseous exudates.
Caseous plugs may be seen in lower trachea or bronchi.
Nephropathic infection causes swollen and pale kidneys.
Fluid yolk material in the abdomen.
Permanent damage of oviduct in day old chicks making them non-layers.
DIAGNOSIS
Based on clinical history
Elisa
Immunofluorescence.
