Infestation

About: Infestation is a research topic. Over the lifetime, 8308 publications have been published within this topic receiving 82305 citations.

Host–parasite interactions in natural holes: marsh tits (Parus palustris) and blow flies (Protocalliphora falcozi)

Abstract: Infestation of marsh tit (Parus palustris, Paridae, Passeriformes) broods by bloodsucking larvae of Protocalliphora falcozi Seguy 1928 (Calliphoridae, Diptera) was studied over an 8-year period in a population breeding in natural holes, in the primeval forest (Bialowieza National Park, eastern Poland). Overall 54% of 222 marsh tit nests were parasitized. Prevalence (27–88%) significantly changed across years. This variation did not depend on the timing of the marsh tit breeding season, or winter/spring temperatures. Frequency of infestation did not depend on forest type or hole attributes. Infestation intensity was rather low (median 8, max. 75 flies/nest, 85% of nests with <3 flies/young). Intensity and prevalence were weakly, but positively, correlated. Larger broods contained significantly more blow flies, but per nestling load did not depend on brood size. No effect of infestation on nestlings was recorded – their mortality did not increase, nor was fledging delayed. In response to the presence of blow flies, parents apparently attempted to increase their feeding rate. There was a clear reproductive cost: 60–63% of female and 68–69% of male marsh tits that had none up to eight blow flies, survived to the next spring, but only 34% of females and 44% of males with more than eight flies/brood did so. It is suggested that the small clutch size of marsh tits could have evolved, inter alia, to reduce the fitness costs of ectoparasites.

Prevalence of anaemia and worm infestation in tribal areas of Madhya Pradesh.

Abstract: The study was conducted among school going children (6-14 years) of Baiga, Abuihmadia and Bharia tribes of Madhya Pradesh to assess the prevalence of anaemia and intestinal parasitic infestation among themselves. A total of 776 school going children were included in the study of whom blood samples of all and stool samples of 409 were collected. Their haemoglobin was measured and stool samples were examined under microscope for ova and cysts. The results revealed that 30.3% of the children had severe anaemia (Hb < 7g/dl) and 50% children had intestinal parasites. The most common parasites were hookworn (16.3%) and A lumbricoides (18.5%). Though hookworm ova loads indicated mild to moderate infestation in most of the children, the continued presence of worms in marginally nourished children could contribute significantly to blood loss in the intestine with resultant anaemia.

Pea aphid infestation induces changes in flavonoids, antioxidative defence, soluble sugars and sugar transporter expression in leaves of pea seedlings.

Abstract: The perception of aphid infestation induces highly coordinated and sequential defensive reactions in plants at the cellular and molecular levels. The aim of the study was to explore kinetics of induced antioxidative defence responses in leaf cells of Pisum sativum L.cv. Cysterski upon infestation of the pea aphid Acyrthosiphon pisum at varying population sizes, including accumulation of flavonoids, changes of carbon metabolism, and expression of nuclear genes involved in sugar transport. Within the first 96 h, after A. pisum infestation, flavonoid accumulation and increased peroxidase activity were observed in leaves. The level of pisatin increased after 48 h of infestation and reached a maximum at 96 h. At this time point, a higher concentration of flavonols was observed in the infested tissue than in the control. Additionally, strong post-infestation accumulation of chalcone synthase (CHS) and isoflavone synthase (IFS) transcription products was also found. The levels of sucrose and fructose in 24-h leaves infested by 10, 20, and 30 aphids were significantly lower than in the control. Moreover, in leaves infested by 30 aphids, the reduced sucrose level observed up to 48 h was accompanied by a considerable increase in the expression level of the PsSUT1 gene encoding the sucrose transporter. In conclusion, A. pisum infestation on pea leads to stimulation of metabolic pathways associated with defence.

Combining Abilities for Maize Stem Antibiosis, Yield Loss, and Yield under Infestation and Non Infestation with Pink Stem Borer

Abstract: Research supported by the Committee for Science and Technology of Spain (project AGF92-0161) and by the Department of Education of the Autonomus Government of Galicia (project XUGA 40301B95).

Heligmosomoides polygyrus reduces infestation of Ixodes ricinus in free-living yellow-necked mice, Apodemus flavicollis

Abstract: Free-living animals are usually inhabited by a community of parasitic species that can interact with each other and alter both host susceptibility and parasite transmission. In this study we tested the prediction that an increase in the gastrointestinal nematode Heligmosomoides polygyrus would increase the infestation of the tick Ixodes ricinus, in free-living yellow-necked mice, Apodemus flavicollis. An extensive cross-sectional trapping survey identified a negative relationship between H. polygyrus and I. ricinus counter to the prediction. An experimental reduction of the nematode infection through anthelmintic treatment resulted in an increase in tick infestation, suggesting that this negative association was one of cause and effect. Host characteristics (breeding condition and age) and habitat variables also contributed to affect tick infestation. While these results were counter to the prediction, they still support the hypothesis that interactions between parasite species can shape parasite community dynamics in natural systems. Laboratory models may act differently from natural populations and the mechanism generating the negative association is discussed.