CURRENT RESPIRATORY DISEASE PROBLEM AND THE
PROBES IN CHICKEN
S.Hasan. K. Ahmad, N. Fawad, B. Siddique and H
Rehman
Poultry Research Institute,
Murree Road,
Rawalpindi
Abstract
Recently,
high mortality was recorded in broiler flocks in various areas of Pakistan. The samples from six
broiler flocks were studied. The blood samples collected were analyzed for
antibodies to Newcastle Disease Virus (NDV), Avian Influenza Virus (AIV),
Infectious Bronchitis Virus (IBV), Infectious Bursal Disease Virus (IBDV),
mycoplasma gallisepticum (MG), Mycoplasma synoviae (MS) and
Salmonella organisms (SPG). It was found that the samples had no antibodies
against NDV, AIV, MG, MS and SPG but variable levels of antibodies were recorded
against IBV and IBDV. Bacteriological examination of the respiratory organs of
clinically sick birds yielded Haemophilus and pathogenic E. coli. The
absence of any pathogen activity in filtrates of 0.2 and 0.1 µm
inoculated through CAM and CAS routes in embryonated eggs ruled out the
possibility of the involvement of AIV and NDV. Unfiltered homogenate and 0.45
µmfiltrate activity indicated the presence of Mycoplasma in the
homogenate. It is concluded that: I. The problem primarily resulted from the
interplay of Mycoplasma, IBDV, IBHV and IBV, 2. Quality of the chicks in
carrying vertical Mycoplasma infection played basic role in the development of
the problem, 3. The associated bacterial pathogens i.e. Infectious Coryza and
Colibacillosis played precipitating role in the problem, 4. Extreme
environmental temperature played a conducive role in the episode and 5.
Predisposing role of mycotoxins in the malady cannot be overlooked.