The present study was undertaken to determine the effect of chronic treatment with two sublethal doses of Dimethoate (organo-phosphorus) or Deltamethrin (pyrethroid) on body weight and semen characteristics in adult male rabbits. Pesticide treatment resulted in a decline in body weight, libido, ejaculate volume, sperm concentration and semen initial fructose; and an increase in abnormal and dead sperm and methylene blue reduction time. In this regard Dimethoate showed greater effects than Deltamethrin. The hazardous effect of these pesticides on semen quality continued during the post-treatment period, and was dose-dependent. This deleterious effect on sperm formation together with the decline in libido suggest a decrease in testosterone secretion by pesticide treatment.

The in vivo effect of dimethoate and deltamethrin on body and organ weights, serum proteins and on plasma acetylcholinesterase (AChE), aromatic esterase and ATPase were examined in growing male rabbits throughout five months period. Both compounds had no significant effect on body weight; however, adrenal, testis & pituitary weights decreased (P less than 0.01); the liver and spleen weights increased (P less than 0.01) in a dose dependent manner. Serum total proteins and globulin decreased (P less than 0.01) in a dose dependent trend, while serum albumin was not greatly affected. AChE activity was increased (P less than 0.01) after 1 month of treatment with the two doses of dimethoate and deltamethrin; thereafter, AChE activity showed 40% inhibition of the control level. The activity of aromatic esterase increased markedly after the first month, then declined gradually until the fifth month. High dose of dimethoate markedly inhibited this enzyme particularly after the 5th month of treatment. Both doses of deltamethrin increased ATPase activity after the first month of treatment, then the ATPase activity was normal. Dimethoate inhibited ATPase particularly at the end of treatment in a dose dependent manner.

Brown snails (Eobania vermiculata), one of the most abundant gastropod of Egyptian farms, which causes many damages for economic crops and ornamentals plants. Methomyl, pirimicarb, and oxamyl as a symbol of carbamates pesticides group, malathion as a symbol of organophosphates pesticides group, thiamethoxam, imidachloprid, and acetamiprid as a neonicotinoid pesticides group symbol, lambda-cyhalothrin as a pyrethroid pesticides group symbol, pymetrozine as a symbol of Antifeedant pesticides group, and the symbols of fungicide pesticides group were carbandazim, and copper sulfate were used against snails, by baiting techniques. Bioassay results showed high activity of methomyl, oxamyl, acetamiprid and lambda-cyhalothrin against E. vermiculata., all over the different times of exposure, after 24 hrs the LC50 values were = 0.259, o.358, 1.049 and 5.976 % respectively, the LC50 values after 48 hrs were = 0.058, 0.90, 0.37 and 0.305 % respectively, the LC50 values after 72 hrs = 0.024, 0.023, 0.129 and 0.187 % respectively, and the LC50 values after 96 hrs = 0.024, 0.004, 0.039 and 0.047 % respectively. Biochemical studies of the four mentioned pesticides showed significantly inhibition effect for snail enzymes: acetylcholinestrase (AChE), carboxyl esterase (CaE), catalase, glutathione-s-transferase (GST) and polyphenoloxidase (PPO). So, these pesticides is promising as a new identification as molluscicides, available in the markets with suitable prices for users, instead of classical molluscicides, which became rarely in the markets and very expensive.

No abstract

Background Spodoptera littoralis is mostly controlled by the use of synthetic insecticides. Nonetheless, the use of these insecticides causes a slew of issues. On this pest, the antifeedant activity of Melaleuca alternifolia essential oil (EO) and its two principal components was investigated. Results The gas chromatography–mass spectrometry (GC/MS) analysis revealed that the M. alternifolia EO was composed of eleven compounds. Terpinen-4-ol (40.1%) and γ-terpinene (21.9%) were chosen as the major constituents. In terms of antifeedant efficacy, treatment with M. alternifolia EO and these components reduced leaf consumption and the efficiency of food conversion in larvae in a concentration-dependent manner. When compared to untreated larvae, weight, growth, and pupation percentage were all significantly lower. Conclusions The findings show that M. alternifolia EO and its components, terpinen-4-ol and γ-terpinene can be effectively combined for cotton leafworm management.