An outbreak of conjunctivitis and severe respiratory disease occurred in an integrated chukar partridge (Alectoris graeca) operation that involved about 8000 birds. The main clinical features were conjunctivitis and sinusitis and frequent mouth breathing, but almost no gasping or coughing. In 1000 breeders, egg production declined from 73% to 20%. Morbidity reached 100%, and losses from mortality and culling approached 60%. At necropsy, a conjunctivitis (often bilateral) and extensive caseated sinusitis were common. There was an occasional slight mucoid tracheitis, but no significant air sac lesions were noted. Mycoplasma gallisepticum, designated strain GM1125, was isolated and identified. Exposure of susceptible chukars to GM1125 reproduced the field disease. GM1125 was reisolated from the conjunctiva of all exposed birds 12 days postinfection, but infrequently from there or the respiratory system 36 days postexposure, even though clinical disease was still present. The experimental disease was confined to the conjunctiva and the upper respiratory tract. An occasional mucoid tracheitis was noted, but generally, the lungs and air sacs were not involved. Infection was followed by an appreciable serological response to M. gallisepticum.

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White leghorn hens naturally infested with northern fowl mites were selected from a producing flock in San Bernardino County. Hens were 31 wk old, well-feathered and in good condition at the start of the test. They were housed in suspended wire cages (3 birds per 30 by 45 cm cage) in an open-sided house typical of this region. The flock had been treated with permethrin for mite control approximately 6 wk earlier, but mites persisted on some birds. Sixty hens were selected which had mite rating scores of 2 or higher (see table). Ten hens of the 60 had mite scores of 5 or higher (a high-level infestation). Four cages of birds (12 hens) were used for each treatment, and empty buffer cages separated each cage of test birds. Treatments were applied with a backpack sprayer at 45 p.s.i., spraying upward toward the vent region of each bird (40 ml per hen). The 3 mite scores for the hens in a particular cage were averaged, and the 4 cage means/date were used as replications in the analysis.

Two field trials were conducted on different ranches to compare acaricides for control of northern fowl mite (NFM) on White Leghorn hens. In Trial 1 Ectiban spray and dust treatments were compared to Rabon and Sevin spray-treatments; egg oil, Rabon, and Sevin sprays were tested in Trial 2. Concentration and rates of application followed label recommendations for the registered compounds. In Trial 1 Ectiban spray gave excellent NFM control; Ectiban dust, Rabon, and Sevin spray treatments resulted in poor NFM control. Egg oil and Rabon sprays gave effective NFM control in Trial 2. Sevin, as in Trial 1, gave poor NFM control. The failure of Sevin to control mites both times suggests the possibility of NFM resistance to this chemical.