tetrachlorvinphos and Poultry-Diseases

Treatment of Northern fowl mite (Ornithonyssus sylviarum) infestation on poultry in research facilities can be challenging. The mite has a rapid reproductive cycle (egg to adult in 5 to 7 d), and chemical treatments can be toxic to birds, personnel, and the environment. In addition, antimite treatment may interfere with experimental research designs. The current study evaluated the efficacy of topical application of an entomopathogenic fungus, Beauveria bassiana, in the treatment of a naturally occurring infestation of Northern fowl mites in pen-housed roosters (n = 14; age, 18 mo). Two groups of 7 roosters each were used in 2 experiments: Beauveria (30 mL, 2.9 × 10(10) spores per bird) compared with water (30 mL, control), and Beauveria compared with the common topical organophosphate agent tetrachlorvinphos-dichlorvos (30 mL). We also assessed a higher dose of Beauveria (300 mL, 2.9 × 10(11) spores per bird) in the 7 birds that were not exposed to tetrachlorvinphos-dichlorvos. Beauveria reduced mite levels relative to the control group but did not outperform tetrachlorvinphos-dichlorvos when used at an equal volume and frequency. Increasing the volume and frequency of Beauveria application improved outcomes such that visual inspection failed to detect any mites. The results presented here suggest that, when applied in sufficient doses, Beauveria effectively reduces mites on poultry and can be an important part of an integrated pest management program. Additional research is needed to document the most effective dose, frequency, and location of B. bassiana application to control Northern fowl mites in poultry.

Topics: Agriculture; Animals; Beauveria; Chickens; Dichlorvos; Housing, Animal; Insecticides; Mite Infestations; Pest Control, Biological; Poultry Diseases; Research; Tetrachlorvinphos; Time Factors

Establishment and spread of Ornithonyssus sylviarum were documented through time on sentinel hens (50 per house of 28,000-30,000 hens) in the first egg production cycle of three large commercial flocks (12 houses) of white leghorn hens. Mites were controlled using acaricide, and the impacts of treatment on mite populations and economic performance were documented. Mite prevalence and intensity increased rapidly and in tandem for 4-8 weeks after infestation. Intensity declined due to immune system involvement, but prevalence remained high, and this would affect mite sampling plan use and development. Early treatment was more effective at controlling mites; 85% of light infestations were eliminated by a pesticide spray (Ravap), versus 24% of heavy infestations. Hens infested later developed lower peak mite intensities, and those mite populations declined more quickly than on hens infested earlier in life. Raw spatial association by distance indices (SADIE), incorporating both the intensity and distribution of mites within a house, were high from week-to-week within a hen house. Once adjusted spatially to reflect variable hen cohorts becoming infested asynchronously, this analysis showed the association index tended to rebound at intervals of 5-6 weeks after the hen immune system first suppressed them. Large, consistent mite differences in one flock (high vs. low infestation levels) showed the economic damage of mite parasitism (assessed by flock indexing) was very high in the initial stages of mite expansion. Unmitigated infestations overall reduced egg production (2.1-4.0%), individual egg weights (0.5-2.2%), and feed conversion efficiency (5.7%), causing a profit reduction of $0.07-0.10 per hen for a 10-week period. Asynchronous infestation patterns among pesticide-treated hens may have contributed to a lack of apparent flock-level economic effects later in the production cycle. Individual egg weights differed with mite loads periodically, but could be either higher or lower, depending on circumstances and interactions with hen weight. Individual hen weight gains were depressed by high/moderate mite loads, but the heavier hens in a flock harbored more mites. This led to compensatory weight gains after mites declined. Tradeoffs between resource allocation to body growth or production versus immune system function appeared to be operating during the early and most damaging mite infestation period, when high egg production was beginning and the hens were gai

Topics: Animal Husbandry; Animals; Chickens; Dichlorvos; Disease Outbreaks; Female; Housing, Animal; Insecticides; Mite Infestations; Mites; Poultry Diseases; Prevalence; Tetrachlorvinphos; Time Factors

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.

Topics: Administration, Topical; Animals; Carbaryl; Chickens; Eggs; Female; Mite Infestations; Oils; Permethrin; Poultry Diseases; Pyrethrins; Tetrachlorvinphos

Formulations of permethrin (Ectiban), a synthetic pyrethroid, as an emulsifiable concentrate (EC), wettable powder (WP), and dust were nearly equally effective for 9 or more weeks for control of the northern fowl mite, Ornithonyssus sylviarum (Canestrini and Fanzago), on caged laying hens under environmentally controlled conditions. The permethrin was applied to the vent area as .05% active ingredient (AI) spray of the diluted EC or WP at 40 ml per bird, .1% AI mist of the diluted EC at 20 ml per bird, and 4.5 g per bird of the .25% AI dust. Dilute sprays of .05% permethrin prepared from the EC and WP and applied at 40 ml per bird were more effective in a commercial caged-laying hen house for northern fowl mite control than were .5% sprays of tetrachlorvinphos (Rabon), Ravap, and carbaryl (Sevin). Satisfactory mite control was obtained with .6% permethrin prepared from the EC and misted at the rate of 2.5 ml per bird. Low volume, high concentration misting of permethrin was a promising method for mite control with satisfactory control achieved with .2% AI at 5 ml per bird and .6% AI at 2.5 ml per bird.

Topics: Aerosols; Animals; Carbaryl; Chickens; Female; Housing, Animal; Insecticides; Mite Infestations; Oviposition; Permethrin; Poultry Diseases; Pyrethrins; Tetrachlorvinphos

Aqueous suspensions of malathion, stirofos, Ravap, and carbaryl formulations (.25 to 1.0%) were tested as dips for control of the northern fowl mite (NFM), Ornithonyssus sylviarum (Canestrini and Fanzago), on caged White Leghorn hens. Hens treated with Ravap showed symptoms of organophosphorus insecticide poisoning soon after treatment and some died as a result of the dip; however, dipping with the other insecticides did not result in any apparent toxic effects. Malathion gave residual control of mites for about 4 weeks posttreatment, but both stirofos and carbaryl dips gave complete control for at least 6 weeks against repeated challenges with the NFM. There were no significant differences in the percent hen-day egg production, feed consumption, or body weight of the hens that could be attributed to any of the chemical treatments.

Topics: Administration, Topical; Animals; Carbaryl; Chickens; Female; Insecticides; Malathion; Mite Infestations; Mites; Pest Control; Pesticide Residues; Poultry Diseases; Species Specificity; Tetrachlorvinphos

Laying hens were treated with a wettable powder formulation of stirofos [Rabon, 2-chloro-1-(2,4,5-trichlorophenyl) vinyl dimethylphosphate] by dipping in a .5 or 1.0% actual ingredient (AI) water suspension of a 50% wettable powder (WP) stirfos formulation. Stirofos residues were detected in eggs within 1 day after treatment and reached maximum levels 3 days after dipping (.021 and .035 ppm in the low- and high-dose birds, respectively). After that time, levels of residues in eggs declined rapidly and no sample contained detectable quantities (less than .004 ppm) of stirofos after 21 days. Dipping may be a practical control method for the northern fowl mite on chickens, because stirofos dips effectively control this mite on laying hens for at least 6 weeks and because resulting residues in eggs are well below established tolerances.

Topics: Administration, Topical; Animals; Chickens; Eggs; Female; Mite Infestations; Pesticide Residues; Poultry Diseases; Tetrachlorvinphos

Fluorescent pigments were used to measure plumage coverage when caged laying hens were dusted for northern fowl mite, Ornithonyssus sylviarum (Canestrini and Fanzago), control. Carriage type electrostatic or high velocity backpack equipment produced superior coverage 2 hr posttreatment when the rates of 454 g (1 lb) dust per 100 or 500 hens was employed. A redistribution of dust was noted 48 hr posttreatment, and a subsequent experiment demonstrated that this phenomenon resulted from intracage cross contamination dependent upon bird caging density. Carbaryl 80% wettable powder (WP) at 454 g/1600 hens and tetrachlorvinphos 50% WP at 454 g/1000 hens provided northern fowl mite control for 11 and 5 weeks posttreatment, respectively.

Topics: Animals; Carbaryl; Chickens; Dust; Female; Housing, Animal; Insect Control; Mite Infestations; Poultry Diseases; Tetrachlorvinphos

Carbaryl and tetrachlorvinphos provided longer lasting control of northern fowl mites, Ornithonyssus sylviarum (Canestrini and Fanzago), than did coumaphos or malathion when the materials were applied to caged laying hens as aqueous sprays. The average duration of residual control was ca. 5 weeks for carbaryl, 4.3 weeks for tetrachlorvinphos, 3.5 weeks for coumaphos, and 2 weeks for malathion. No presumptive evidence of northern fowl mite resistance to carbaryl or tetrachlorvinphos was encountered. In contrast, malathion often failed to produce satisfactory control, and difficulty with adequate dispersion of coumaphos wettable powder was noted.

Topics: Animals; Carbaryl; Chickens; Coumaphos; Drug Evaluation; Insecticides; Malathion; Mite Infestations; Poultry Diseases; Tetrachlorvinphos