ABSTRACT
Electrophoretic studies were carried out on isozymes of 3 populations of Anopheles minimus collected from Guangxi and Yunnan Provinces of the People's Republic of China in 1993. Eight proteins were analyzed by 5% polyacrylamide gel electrophoresis. The most variable population, 'Yunnan-Field' (Y-F), was highly polymorphic at 14 of 20 loci (P = 0.700) with an average heterozygosity H of 0.340. P values of 0.500 and 0.700, and H values of 0.220 and 0.210 were obtained for each from 'Guangxi-Lab' (GX-L) and 'Yunnan-Lab' (Y-L), respectively, Nei's genetic distances (D) between Y-L and GX-L, Y-F and GX-L, and Y-F and Y-L were 0.1131, 0.1946 and 0.1069, respectively. These results suggest that GX-L is distant from the 2 other populations, Y-L and Y-F, and that this genetic differentiation between the 2 populations of Yunnan and Guangxi Provinces corresponds to the forms A and B, which were morphologically classified by Xu et al (unpublished).
Subject(s)
Animals , Anopheles/genetics , China , Electrophoresis, Polyacrylamide Gel , Female , Gene Frequency , Genetic Variation , Genetics, Population , Isoenzymes/geneticsABSTRACT
Electrophoretic studies were carried out on isozymes of 3 populations of Anopheles minimus collected from Guangxi and Yunnan Provinces of the People's Republic of China in 1993. Eight proteins were analyzed by 5% polyacrylamide gel electrophoresis. The most variable population, Y-F, was highly polymorphic at 14 of 20 loci (P=0.700) with an average heterozygosity H of 0.340. P values of 0.500 and 0.700, and H values of 0.220 and 0.210 were obtained for each from 'Guangxi-Lab' (GX-L) and 'Yunnan-Lab' (Y-L), respectively. Nei's genetic distances (D) between Y-L and GX-L, Y-F and GX-L, and Y-F and Y-L were 0.1131, 0.1946 and 0.1069, respectively. These results suggest that GX-L is distant from the 2 other populations, Y-L and Y-F, and that this genetic differentiation between the 2 populations of Yunnan and Guangxi Provinces corresponds to the forms A and B, which were morphologically classified by Xu et al (unpublished).
Subject(s)
Alleles , Animals , Anopheles/genetics , China , Electrophoresis, Polyacrylamide Gel , Genetic Variation , Insect Proteins/geneticsABSTRACT
Effect of different numbers of infecting Brugia malayi on the survival of Anopheles sinensis were quantitatively studied in our laboratory. Four groups of healthy adult female mosquitos were tested. They were named G-0, G-1, G-2 and G-3, in which the numbers of microfilariae (mf) infecting per mosquito were 0, 5, 10 and 50, respectively. The experimental infection was conducted by inoculating the mf into the bodies of mosquitos through the neck membrane with a microinjector. It was observed that, in the groups from G-0 to G-3, the maximal life-span postinoculation (PI) were 21, 21, 20 and 10 days, the average life-spans PI were 7.78, 7.98, 7.05 and 3.55 days, and the survival time at 50% mortality PI were 6.72, 6.80, 6.40 and 4.00 days, respectively. Daily survival rates in the groups G-0, G-1 and G-2 declined slowly, over 25% on the 10th day PI, whereas the one in the group G-3 dropped down quickly, to zero on the same day. Linear regression analysis on the daily survival rates against the days PI showed significant differences between the groups G-0 and G-3 (0.02 > p > 0.01), but no significant differences between the groups G-0 and G-1, or between G-0 and G-2 (p > 0.5).
Subject(s)
Animals , Anopheles/growth & development , Brugia malayi/pathogenicity , China , Female , Host-Parasite Interactions , VirulenceABSTRACT
Definite numbers of B. malayi mf were inoculated into An. sinensis and Cx. quinquefasciatus, and their subsequent development was observed. The relationships between the dosage and the L3 positive rate on the one hand and the average filarial maturity rate on the other were defined. At the same dosages of 4 and 10 mf/mosquito, the L3 positive rates and the average filarial maturity rates in An. sinensis were much higher than those in Cx. quinquefasciatus (p less than 0.01). It was demonstrated that the immune response to filariae of the mosquitos was the main factor resulting in these differences. The intensity of the immune response not only varied with the species, but also declined with the aging of mosquitos. The results of our experiment might be useful to studies on the dynamics of filariasis transmission and the interaction between filariae and their insect hosts.