الفهرس 
Entomological studiesOnly 14 pages are availabe for public view
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Abstract
Sali\.ary glands of mosquitoas play an important role in the develop men: and transmission of protozoan and arbviral agents. They produce secretions which elicit allergic responses to the bites of these noxious insects, therefore, they recieved z great deal of attention. This attention has been somewhat restricted to their gross morphology and histology regardless of the mosquito age. In an attempt to fill this gap of knowledge, the histological and histochemical changes accompanying development and blood feeding were studied in two Egyptian mosquitoes, Culex pipiens and Aedes caspius. Morever, changes in total protein levels as well as protein fractions were also investigated. results obtained from the present study a r e summarized hereafter: Morpholagical changes: The salivary glands of both female mosquitoes consist of paired trilobed structure composed of one median and two lateral lobes. Daily examination of the mosquito salivary glands indicated that immediately after emergence these lobes were small, thin and unconvoluted. There were no obvious difference in size among the lobes and no division into a neck and acinus was apparent at this stage of development. By the third day post emergence the glands of both species were completely matured as the lobes increased in length and be c ame more convolured. spatially In -Ae. caspius. Each lateral lobe was di\.isible intothree regions: proximal (ac~nus). intermediate (neck) and distal (acinus). While the median lobe was divided into two regions: distal (acinus) and neck region. Histological changes: Histological preparations were stained with Ehrlish’s Haematoxylin and eosin which gave good results when examined daily post emergence. The epithelial cells were small, deeply stained and coarsely granulated with a centrally situated nucleus. In mature glands these cells were gradually distended with secretions which filled the g r e a t e r p a r t of the acinar cells while the nucleus became more peripherally situated. Immediately after blood feeding there was no significant change in the cytological picture, while after 24 hours the nucleus increased greatly in size and the basophilia increased around it. During the following daysthe nucleus returned to the resting s t a t e and the cytoplasm become more coarsely granular. Hitochemical changes in salivary gland proteins contents in Culer - Culex pipiem: The bromophenol blue method for protein staining gives satisfactory results. It was observed that 24 hours post emergence the cells of both median and lateral lobes of the test mosquitoes contained low intensity of protein. However the intensity of the blue colour was lower in the lateral lobes as compared to the median lobe. The colour increased gradually till t h e 3r- d- day post emergence.After blood feeding t h e protein intensity reached i t s maximum at t h e 5-t h day. - Aedes caspius One, two and three days post emergence the salivary gland cells stained blue, but thls colour was very faint in thelateral lobes as compared to the median lobe. However, the protein content i n t h t h lateral lobes increased nearly 2-3 folds during the 4- and 5- day post emergence. After blood feeding no changes occurred in the median lobe, while in the lateral lobes the protein content increased through t h e 2- nd and 3- r d days only. Total salivary gland proteins in Culex-iens and Aedes cas~iux The more rapidly and sensitive method of Bradford used in this study gave good results specially for the small quantity of the samples used. - Culex pipiens: Total protein increased gradually post emergence f rom 4.94 -+ 0.45 pglgland t o reach i t s maximum a t t h e 3-rd day 6.60 + 0.37 pglgland. Af t e r blood feeding i t decreased about 55-60% (2.37 -+ 0.44 pglgland). Dw-ing t h e 2- nd through t h e 4- t h day a f t e r blood feeding t h e protein increased again t o reach its value attained prior to blood feeding (7.46 -- 0.40 pglgland) t h e n in t h e r e s t t h r e e days t h e t o t a l protein remained nearly constant. - Aedes caspius: The protein content in &. caspius salivary glands was found t o be nearly similar during the first four days post emergence(range 3.13 -+ 0.27 - 3.91 -+ 0.36 &gland). The amount of protein then increased about 2-folds in t h e 5-t h day post emergence t o r e a ch 7.38 -+ 0.78 pg/gland. During the three days following blood feeding, protein contents increased sharply to amount as twice as much the amount determined before feeding (15.50 -+ 0.96 &gland). By day 4 post blood feeding, after oviposition, a great decrease in the protein contents (4.1 3 -+ 0.56 &gland) was observed. However, t h e level of proteins soon started to increase again slightly during the following three days.