| diseases of free-ranging chickens in the qwa-qwa district of the northeastern free state province of south africa. | a total of 177 free-ranging chickens from 19 qwa-qwa villages were bled from wing veins over a period of 6 months (june-november 2000). serological tests indicated that 5% of chickens tested had been exposed to newcastle disease, 43% to infectious bronchitis and 63% to mycoplasma gallisepticum infection. mcmaster and visser sieve techniques were used to determine helminth and coccidia from pooled fresh faecal samples. helminths isolated in 37% of the villages investigated were heterakis, ascarid ... | 2003 | 12836740 |