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Browsing by Author "Polanco, Andrea M."

Now showing 1 - 7 of 7
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    Bed Bug Biology and Behavior
    Miller, Dini M.; Polanco, Andrea M.; Rogers, Jeffrey (Virginia Cooperative Extension, 2013)
    This publication discusses bed bug biology and behavior.
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    Bed Bug Biology and Behavior
    Miller, Dini M.; Polanco, Andrea M.; Rogers, Jeffrey (Virginia Cooperative Extension, 2019-03-18)
    Discusses bed bug biology and behavior.
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    Como Identificar Infestaciones de Chinches
    Miller, Dini M.; Polanco, Andrea M.; Rogers, Jeffrey (Virginia Cooperative Extension, 2012)
    This publication discusses bed bugs, their behavior, and signs of infestation.
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    Life History of the Common Bed Bug Cimex lectularius L. in the U.S.
    Polanco, Andrea M. (Virginia Tech, 2011-01-11)
    This study quantifies the rate of bed bug nymphal development, mortality, fecundity and survivorship during starvation for wild caught resistant populations. I then compare some of these characteristics with two susceptible strains. I found that resistant populations develop faster and exhibit less mortality per life stage than susceptible populations. However, there were no significant differences in the total number of eggs produced by the resistant females from the field strains during the 13 feedings/oviposistion cycles (P = 0.106). On average, resistant females from the field strains produced 0.74 eggs per day. Susceptible strains survived a significantly longer time without feeding (89.2 d and 81.4 d) than the resistant strains (RR, ER). The mean duration of adult life (from the day the female becomes an adult until the day she dies) for (RR) strains was 118.7 d ° 11.8 SE. The intrinsic rate of increase r or average daily output of daughter eggs by female was 0.42. The net reproductive rate Rₒ, indicated that one live female egg would, on the average, be replaced by approximately 35 females. Resistant and susceptible populations were found to be different in terms of development, survivorship, and fecundity. The differences between susceptible and resistant strains could be explained by a trade-off between the alleles that confer resistance and the fitness in the population. When compare the stable age distribution of a pyrethroid susceptible strain (HS) and a resistant strain (RR) there were not significant differences (?°= 9.0066, df = 6, P = 0.1732) in the stable age distribution, basically both strains were dominated by the egg stage. No significant difference was found in the expected reproductive contribution of the various life stages to future population size between the two strains (?°= 1.5458, df = 6, P = 0.9564). Despite this, the reproductive contributions of life stages other than eggs were generally higher for the HS strain than for the RR strain. For both strains changes in P? for the adult stage are expected to have the greatest impact on?? compared with changes in P? for the other life stages. The key to the reduction of the populations of bed bugs lies with the reduction of survival of the adults.
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    Population Growth Potential of the Bed Bug, Cimex lectularius L.: A Life Table Analysis
    Polanco, Andrea M.; Brewster, Carlyle C.; Miller, Dini M. (MDPI, 2011-04-29)
    Experimental life tables were constructed and analyzed for three strains of the common bed bug: a pyrethroid-susceptible laboratory strain (HS), a highly resistant field strain (RR), and a field strain with a declining level of resistance (KR). Egg to adult survival in the RR strain was 94% compared with 79% and 69% in the HS and KR strains, respectively. The RR strain also developed significantly faster from egg to adult (~35 days) than the other two strains (~40 days). Analysis of a survivorship and fecundity life table for the RR strain produced the following results. The average life expectancy for a newly laid egg was ~143 days, and that of a newly molted adult was ~127 days. Females produced an average of 0.64 daughter eggs/day with the highest weekly production during the fifth week of adult life. Analysis of daily reproductive parity showed that females produced 1-3 and 4-6 eggs on 79 and 21% of the days, respectively, when egg laying occurred. The net reproductive rate (R0) of the RR strain was ~35, which represents a 35-fold increase in the population per generation (~92 days). The intrinsic rate of increase, r, was 0.054 indicating that the population multiplies 1.1 times/female/day (_) and doubles in size every 13 days. The stable age distribution (cx) was dominated by nymphs (54%), followed by eggs (34%) and adults (12%). Reproductive values (vx) for the strain increased from egg to the adult stage.
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    Reproductive Potential of Field-collected Populations of Cimex lectularius L. and the Cost of Traumatic Insemination
    Polanco, Andrea M.; Miller, Dini M.; Brewster, Carlyle C. (MDPI, 2011-07-05)
    Egg production was compared among three field-collected bed bug strains over the course of 13 feeding/oviposition cycles, each of which lasted ~10 days. No significant differences were found among bed bug strains in the mean number of eggs/female/day (~1.0 egg). However, significant differences were found among strains in their patterns of egg production throughout the study period. Specifically, differences were observed in the timing of peak egg production and the rapidity of egg production decline among the three strains. Egg production was also quantified for female bed bugs that were subjected to single or multiple traumatic insemination events over a period of six feeding/oviposition cycles. Significant differences were found in egg production between females exposed to single and multiple inseminations. Females mated only once produced 83.8 4.5 (mean SE) eggs over six feeding cycles. Females exposed to multiple inseminations produced 61.0 3.1 eggs, indicating that multiple traumatic inseminations may reduce female fecundity by as much as 27%. This study is the first to suggest that, in a new infestation (first ~6 weeks), a solitary, singly-mated female with access to regular blood meals is capable of producing greater numbers of offspring than the same female in the presence of a male.
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    Survivorship During Starvation for Cimex lectularius L.
    Polanco, Andrea M.; Miller, Dini M.; Brewster, Carlyle C. (MDPI, 2011-05-11)
    Four bed bug strains (Cimex lectularius) with different levels of pyrethroid resistance were evaluated to determine their ability to survive extended periods of starvation. First instar bed bugs of all strains were the most vulnerable to starvation (13.8-36.3 days mean survival time). Fifth instars and adults survived the longest during starvation (41.5-142.6 days). Significant differences in survivorship during starvation were observed between resistant and susceptible strains of bed bugs. Overall, all immature and adult stages of the resistant bed bug strains had significantly shorter survival times than those of the susceptible strains (P < 0.05).