Data from: Fitness consequences of altered feeding behavior in immune-challenged mosquitoes

Background: Malaria-infected mosquitoes have been reported to be more likely to take a blood meal when parasites are infectious than when non-infectious. This change in feeding behavior increases the likelihood of malaria transmission, and has been considered an example of parasite manipulation of host behavior. However, immune challenge with heat-killed Escherichia coli induces the same behavior, suggesting that altered feeding behavior may be driven by adaptive responses of hosts to cope with an immune response, rather than by parasite-specific factors. Here we tested the alternative hypothesis that down-regulated feeding behavior prior to infectiousness is a mosquito adaptation that increases fitness during infection. Methods: We measured the impact of immune challenge and blood feeding on the fitness of individual mosquitoes. After an initial blood meal, Anopheles stephensi Liston mosquitoes were experimentally challenged with heat-killed E. coli at a dose known to mimic the same temporal changes in mosquito feeding behavior as active malaria infection. We then tracked daily egg production and survivorship of females maintained on blood-feeding regimes that either mimicked down-regulated feeding behaviors observed during early malaria infection, or were fed on a four-day feeding cycle typically associated with uninfected mosquitoes. Results: Restricting access to blood meals enhanced mosquito survival but lowered lifetime reproduction. Immune- challenge did not impact either fitness component. Combining fecundity and survival to estimate the population- scale intrinsic rate of increase (r), we found that, contrary to the mosquito adaptation hypothesis, mosquito fitness decreased if blood feeding was delayed following an immune challenge. Conclusions: Our data provide no support for the idea that malaria-induced suppression of blood feeding is an adaptation by mosquitoes to reduce the impact of immune challenge. Alternatively, the behavioral alterations may be neither host nor parasite adaptations, but rather a consequence of constraints imposed on feeding by activation of the mosquito immune response, i.e. non-adaptive illness-induced anorexia. Future work incorporating field conditions and different immune challenges could further clarify the effect of altered feeding on mosquito and parasite fitness.Data: Altered feeding behavior in mosquitoes and associated fitness parametersData includes life history data for a total of 921 individual mosquitoes, each numbered with a unique id number given in the first column. Feed.D4-Feed.D16 describe feeding compliance with -1 meaning offered a blood meal but not taken, 1 meaning offered and fed, and 0 meaning not offered a blood meal and, thus not fed. DOD represents day of death and is the day a mosquito was observed to die, counting day 0 as the first day of the experiment and 24 as the last day of the experiment. Natural.LH indicates whether a mosquito died naturally (1) or not (0). Dying unnaturally include deaths by experimental handling or escape from container. Wing length is the length of the right wing in mm. Immune and Feeding treatments indicate which experimental group the mosquito was placed in. Replicate indicates which of two experimental replicates the mosquito was in, with "5" taking place in Spring 2015, and "6" taking place in Summer/Fall 2015. Replicate.end indicates the number of adult days over which experimental observations took place. Fitness is the estimate of individual intrinsic rate of increase, r, based on the survival and reproduction data for that individual (methods for modeling r described in Ohm 2016). Clutch1-Clutch5 are the sums of eggs produced for each individual after each blood meal, for example Clutch 1 is the sum of eggs an individual produced after the first blood meal Clutch 2, after the second, etc. d0-d23 list the number of eggs each individual laid for that day, from d0 (the start of the experiment) to d23 (last day of the experiment). Age is the final age of the mosquito on it's death day, adding the average length of time spent in the juvenile stage to it's observed death day. tot_r is a slightly different calculation of r that used different assumptions in its calculation not discussed in Ohm et al 2016.All life table data - all(1).cs