Chronic Respiratory Disease (CRD) in Poultry

Mycoplasma gallisepticum is a bacteria and a major cause of Chronic Respiratory Disease (CRD) in poultry. The bacteria then causes major damage to the chicken respiratory system.

M. gallisepticum spreads via eggs, airborne transmission and indirect or mechanical routes such as introducing infected chicken to an existing flock, or via chicken transport containers. M. gallisepticum can reside in a flock with few indications of its presence until the flock or individuals in it are stressed sufficiently to show signs of respiratory disease.

SIGNS OF CRD

The most common symptoms of CRD are head shaking, clear weeping eyes and swelling around the head and sinuses. In more advanced cases of CRD in poultry see open mouth breathing, gurgling and a smelly pus build up in the oral cavity and eyes. Chicken are anorexia and slow growth, decrease reproductive rate up to 10-40%, low hatched rate and weak chicks.

Other diseases that have similar clinical signs are Infectious Coryza, Infectious bronchitis, Infectious laryngotracheitis and Fowl cholera.

PREVENTION

– Vaccine

+ Live-attenuated vaccine is usually use for broilers and laying hens from 2 weeks of age – single dose injection.

+ Inactivated vaccine is often use for breeder.

Nursing Care

– Housing must be well ventilated, periodic disinfection, the incubator must be disinfected well.

– Fully supply various kind of vitamin, especially is Vitamin A, Vitamin C, Bcomplex, Electrolytes to improve immunity.

TREATMENT

Antibiotics

Doxycycline – is a great antibiotic against Mycoplasma.

Tylosin can also be used alone but is usually use it with Doxycycline.

Lincomycin combined with Spectinomycin, is water antibiotic works well and has no withholding period for egg layers.

Chortetracycline – works okay not as good as Doxycycline but has no withholding period for egg layers.

Enrofloxacin – is a great antibiotic against Mycoplasma, and other secondary bacteria.

Amoxicillin and Clavulonic acid is often used in conjunction to treat secondary bacterial infections.

The poultry vets also use antibiotic eye drops and Antibiotic nose drops. This route of medication is brilliant as the drugs get right to the place of infection.