Evaluation of phosmet for the control of the common scabies mite on cattle.

Thirty-four young range cattle heavily infested with the common scabies mite, Psoroptes ovis, were dipped in phosmet (O,O-dimethyl phosphorodithioate S-ester with N-(mercaptomethyl)phthalimide) in 15 trials. All concentrations from 0.15% to 0.25% that were applied once failed in at least one trial, but all concentrations from 0.075% to 0.20% were successful in eradicating mites when used twice at 7- to 10-day intervals. One single dip tried at 0.30% also was successful. Uninfested yearlings were dipped in 0.30% phosmet without apparent intoxication, but 2-year-old cattle treated in a spray-dip machine at 0.40% active ingredient became depressed and stiff gaited.

Insect juvenile hormone mimics against the short-nosed cattle louse, Haematopinus eurysternus Denny (Anoplura), and their effect on warbles of Hypoderma sp. Latr. (Diptera:Oestridae).

Insect juvenile hormone mimics (IJH) at 0.1 and 0.01% were used as sprays for control of the short-nosed cattle louse, Haematopinus eurysternus Denny, on 11 heavily infested Hereford cows. A significant reduction of lice occurred although eradication was achieved in only one case. Severe reactions, apparently associated with the death or failure of complete development of cattle grub larvae, Hypoderma sp. Latr., were seen in the IJH-treated cows.