Samples from three different mating stages (before, during and after mating) of the Mediterranean fruit fly Ceratitis capitata were used in this experiment. Samples obtained from whole insects were subjected to extraction with the two mixtures of solvents (acetonitrile/water (A) and methanol/acetonitrile/water (B)) and a comparative study of the extractions using the different solvents was performed. Direct immersion-solid phase microextraction (DI-SPME) was employed, followed by gas chromatographic-mass spectrometry analyses (GC/MS) for the collection, separation and identification of compounds. The method was validated by testing its sensitivity, linearity and reproducibility. The main compounds identified in the three different mating stages were ethyl glycolate, α-farnesene, decanoic acid octyl ester, 2,6,10,15-tetramethylheptadecane, 11-tricosene, 9,12-(Z,Z)-octadecadienoic acid, methyl stearate, 9-(Z)-tricosene, 9,11-didehydro-lumisterol acetate; 1,54-dibromotetrapentacontane, 9-(Z)-hexadecenoic acid hexadecyl ester, 9-(E)-octadecenoic acid and 9-(Z)-hexadecenoic acid octadecyl ester. The novel findings indicated that compound compositions were not significantly different before and during mating. However, new chemical compounds were generated after mating, such as 1-iodododecane, 9-(Z)-tricosene and 11,13-dimethyl-12-tetradecen-1-acetate which were extracted with both (A) and (B) and dodecanoic acid, (Z)-oleic acid, octadecanoic acid and hentriacontane which were extracted with (A) and ethyl glycolate, 9-hexadecenoic acid hexadecyl ester, palmitoleic acid and 9-(E)-octadecenoic acid, which were extracted with solvent (B). This study has demonstrated that DI-SPME is useful in quantitative insect metabolomics by determining changes in the metabolic compounds in response to mating periods. DI-SPME chemical extraction technology might offer analysis of metabolites that could potentially enhance our understanding on the evolution of the medfly.

Optimization and Validation for Determination of Volatile Organic Compounds from Mediterranean Fruit Fly (Medfly) Ceratitis capitata (Diptera: Tephritidae) by Using HS-SPME-GC-FID/MS

This experiment was applied in animal production fields (Sheikh Saad district) which located in Wasit governorate, Wasit, Iraq for sheep rearing. The experiment was started 20/1/2022- 20/4/2022, proceeded for 14 days introductory period. The aim of study was to add four different levels of fast and slow decomposition of urea in blood samples of Awassi sheep. Sixteen males of Awassi sheep aged (3-4) months have been used, with an average initial weight of (16.5-18) ± 500 g. There was a significant difference (P≤0.05) in the pH value of the rumen fluid in relation to the 0/h before the morning feeding for the third treatment, which was added to its diets: fast and slow decomposition urea (0.5%-1.5%) mg/kg dry matter was 6.60 compared with the first, second treatment and the fourth one, as it reached 6.94, 6.82 and 6.86, respectively.The results also showed that the addition of different percentages of fast and slow decomposition urea to a significant increase (P < 0.05) in the concentration of volatile fatty acids in the rumen at 0/h, where the fourth treatment excelled which reaching 79.12 mmol compared to the first, second and third treatment, which were 65.01 and 68.24 and 73.64 mmol, respectively. There was a significant decrease (P<0.05) in the concentration of ammonia nitrogen in the rumen at 0 hour, as the fourth and third treatment recorded 7.89 and 8.82, respectively, while with the first and second treatment recorded 12.51 and 11.46, respectively. In addition, there are no significant differences in the concentration of urea in the blood between the experimental treatments added to it of fast hydrolyzed urea and slow hydrolyzed urea at different levels. Finally, there were significant differences (P≤0.05) in the concentration of triglycerides in the blood for the sixth week, where the first treatment, which added 2% urea, exceeded the rate of decomposition to its diet. It reached 69.16 mg/100 ml compared with the second, third and fourth treatment. They were ranged 68.24, 67.92, and 67.99 mg, respectively.