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K J Mcdowell - One of the best experts on this subject based on the ideXlab platform.
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eastern tent caterpillars Malacosoma americanum cause mare reproductive loss syndrome
Journal of Insect Physiology, 2004Co-Authors: Bruce A Webb, Walter E Barney, D L Dahlman, Stephanie N Deborde, Claire Weer, Neil M Williams, J M Donahue, K J McdowellAbstract:Abstract A new equine abortigenic disease, mare reproductive loss syndrome (MRLS), was recognized and significantly impacted the Ohio Valley in the springs of 2001 and 2002. MRLS caused ~$ 330 million in losses in 2001. An epidemiological investigation of MRLS associated occurrence of the disease with exposure to eastern tent caterpillars ( M. americanum ). This work investigates the epidemiological association between M . americanum and MRLS to determine if this association was correlative or causative. A pilot study and Experiment 1 simulated exposure to M . americanum and their excreta on pasture grasses. The pilot study advanced exposure of pregnant mares to M . americanum materials and 18 of the 29 mares in the study aborted with symptoms of MRLS before other cases were reported in the region. In Experiment 1 , three of seven mares exposed to M . americanum aborted, while mares in control ( n =6) and M . americanum frass ( n =7) treatments had no losses. In Experiment 2 , mares were fed frozen insect larvae in feed buckets mixed with oats. Abortions occurred in three of five mares receiving frozen M . americanum , while mares that were fed autoclaved M . americanum ( n =5) or frozen gypsy moth larvae ( n =4) had no abortions due to MRLS. In Experiment 3 , M . americanum larvae were dissected and fractionated. Statistically significant numbers of abortions occurred only in the positive control group and in association with the M . americanum exoskeleton. All abortions induced by exposure to M . americanum exhibited changes in echogenicity of fetal fluids and bacteriological findings post abortion that were consistent with MRLS. These studies support the hypothesis that ingestion of M . americanum larvae induces the MRLS-type equine abortions, and provide experimental evidence that this lepidopteran larva can cause an abortigenic disease in a vertebrate host.
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eastern tent caterpillars Malacosoma americanum cause mare reproductive loss syndrome
Journal of Insect Physiology, 2004Co-Authors: Bruce A Webb, Walter E Barney, D L Dahlman, Stephanie N Deborde, Claire Weer, Neil M Williams, J M Donahue, K J McdowellAbstract:A new equine abortigenic disease, mare reproductive loss syndrome (MRLS), was recognized and significantly impacted the Ohio Valley in the springs of 2001 and 2002. MRLS caused approximately 330 million US dollars in losses in 2001. An epidemiological investigation of MRLS associated occurrence of the disease with exposure to eastern tent caterpillars (M. americanum). This work investigates the epidemiological association between M. americanum and MRLS to determine if this association was correlative or causative. A pilot study and simulated exposure to M. americanum and their excreta on pasture grasses. The pilot study advanced exposure of pregnant mares to M. americanum materials and 18 of the 29 mares in the study aborted with symptoms of MRLS before other cases were reported in the region. In, three of seven mares exposed to M. americanum aborted, while mares in control (n=6) and M. americanum frass (n=7) treatments had no losses. In, mares were fed frozen insect larvae in feed buckets mixed with oats. Abortions occurred in three of five mares receiving frozen M. americanum, while mares that were fed autoclaved M. americanum (n=5) or frozen gypsy moth larvae (n=4) had no abortions due to MRLS. In, M. americanum larvae were dissected and fractionated. Statistically significant numbers of abortions occurred only in the positive control group and in association with the M. americanum exoskeleton. All abortions induced by exposure to M. americanum exhibited changes in echogenicity of fetal fluids and bacteriological findings post abortion that were consistent with MRLS. These studies support the hypothesis that ingestion of M. americanum larvae induces the MRLS-type equine abortions, and provide experimental evidence that this lepidopteran larva can cause an abortigenic disease in a vertebrate host.
Martin A Erlandson - One of the best experts on this subject based on the ideXlab platform.
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isolation and characterization of plaque purified strains of Malacosoma disstria nucleopolyhedrovirus
Canadian Journal of Microbiology, 2006Co-Authors: Martin A Erlandson, Doug Baldwin, Melissa Haveroen, Andrew B KeddieAbstract:Seven plaque-purified genotypic variants or strains, derived from a previously described field isolate of the Malacosoma disstria Nucleopolyhedrovirus (MadiNPV) from Alberta populations of forest tent caterpillar, were characterized based on distinctive restriction endonuclease fragment patterns. Two strains, MadiNPV-pp3 and MadiNPV-pp11, were selected for further characterization, as they represented strains producing high and low budded virus (BV) titres, respectively, in the M. disstria cell line UA-Md203. Analysis of restriction endonuclease fragment profiles indicated the genomes differed significantly in size, 133.8 +/- 2.4 kb for MadiNPV-pp3 and 118.1 +/- 3.5 kb for MadiNPV-pp11. These strains were characterized based on their BV production in three different cell lines derived from M. disstria haemocytes. Compared with MadiNPV-pp11, MadiNPV-pp3 produced two- to three-fold more BVs in UA-Md203 and 210 other cell lines; however, BV production was only marginally higher for MadiNPV-pp3 in the UA-Md221 cell line. Similarly, the yield of polyhedral inclusion bodies was significantly higher for MadiNPV-pp3 in UA-Md203 and 210 cell lines than for MadiNPV-pp11 but not in the UA-Md221 cell line. This data, although derived from a limited number of cell lines, suggested MadiNPV-pp3 may have a broader tissue tropism than MadiNPV-pp11.
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establishment and characterization of three Malacosoma disstria cell lines
Journal of Invertebrate Pathology, 1995Co-Authors: Andrew B Keddie, Martin A Erlandson, Gerald J HilchieAbstract:Three cell lines were established from Malacosoma disstria hemocytes. Although the morphology, growth rates, isozyme patterns, and adherence characteristics of these cell lines (UA-Md203, UA-Md210, and UA-Md221) were different, all supported virus replication (AcMNPV and MdMNPV-A92). One cell line, UA-Md221 was extremely adherent and could not be removed by enzymatic treatment. Few cells were loosened or damaged by 2-hr incubations in trypsin, collagenase or enzyme mixture. We hypothesize that these cells inactivate these enzymes.
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characterization of a nuclear polyhedrosis virus from the forest tent caterpillar Malacosoma disstria
Journal of Invertebrate Pathology, 1995Co-Authors: Andrew Keddie, Martin A ErlandsonAbstract:Abstract A nuclear polyhedrosis virus (NPV) isolated from Malacosoma disstria larvae was characterized biochemically and immunologically. Restriction enzyme patterns were compared with those of NPV from M. alpicola (MaNPV) and Autographa californica (AcMNPV). Polyclonal antibodies were made to M. disstria NPV and used for immunoblots. This virus isolate, designated MdMNPV, contains virions with multiple nucleocapsids, an estimated genome of 130.4 ± 3.3 kb, and a restriction pattern distinct from that of MaNPV. Immunoblotting detected cross-reactivity among numerous structural proteins of MdMNPV and AcMNPV.
Bruce A Webb - One of the best experts on this subject based on the ideXlab platform.
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eastern tent caterpillars Malacosoma americanum cause mare reproductive loss syndrome
Journal of Insect Physiology, 2004Co-Authors: Bruce A Webb, Walter E Barney, D L Dahlman, Stephanie N Deborde, Claire Weer, Neil M Williams, J M Donahue, K J McdowellAbstract:Abstract A new equine abortigenic disease, mare reproductive loss syndrome (MRLS), was recognized and significantly impacted the Ohio Valley in the springs of 2001 and 2002. MRLS caused ~$ 330 million in losses in 2001. An epidemiological investigation of MRLS associated occurrence of the disease with exposure to eastern tent caterpillars ( M. americanum ). This work investigates the epidemiological association between M . americanum and MRLS to determine if this association was correlative or causative. A pilot study and Experiment 1 simulated exposure to M . americanum and their excreta on pasture grasses. The pilot study advanced exposure of pregnant mares to M . americanum materials and 18 of the 29 mares in the study aborted with symptoms of MRLS before other cases were reported in the region. In Experiment 1 , three of seven mares exposed to M . americanum aborted, while mares in control ( n =6) and M . americanum frass ( n =7) treatments had no losses. In Experiment 2 , mares were fed frozen insect larvae in feed buckets mixed with oats. Abortions occurred in three of five mares receiving frozen M . americanum , while mares that were fed autoclaved M . americanum ( n =5) or frozen gypsy moth larvae ( n =4) had no abortions due to MRLS. In Experiment 3 , M . americanum larvae were dissected and fractionated. Statistically significant numbers of abortions occurred only in the positive control group and in association with the M . americanum exoskeleton. All abortions induced by exposure to M . americanum exhibited changes in echogenicity of fetal fluids and bacteriological findings post abortion that were consistent with MRLS. These studies support the hypothesis that ingestion of M . americanum larvae induces the MRLS-type equine abortions, and provide experimental evidence that this lepidopteran larva can cause an abortigenic disease in a vertebrate host.
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eastern tent caterpillars Malacosoma americanum cause mare reproductive loss syndrome
Journal of Insect Physiology, 2004Co-Authors: Bruce A Webb, Walter E Barney, D L Dahlman, Stephanie N Deborde, Claire Weer, Neil M Williams, J M Donahue, K J McdowellAbstract:A new equine abortigenic disease, mare reproductive loss syndrome (MRLS), was recognized and significantly impacted the Ohio Valley in the springs of 2001 and 2002. MRLS caused approximately 330 million US dollars in losses in 2001. An epidemiological investigation of MRLS associated occurrence of the disease with exposure to eastern tent caterpillars (M. americanum). This work investigates the epidemiological association between M. americanum and MRLS to determine if this association was correlative or causative. A pilot study and simulated exposure to M. americanum and their excreta on pasture grasses. The pilot study advanced exposure of pregnant mares to M. americanum materials and 18 of the 29 mares in the study aborted with symptoms of MRLS before other cases were reported in the region. In, three of seven mares exposed to M. americanum aborted, while mares in control (n=6) and M. americanum frass (n=7) treatments had no losses. In, mares were fed frozen insect larvae in feed buckets mixed with oats. Abortions occurred in three of five mares receiving frozen M. americanum, while mares that were fed autoclaved M. americanum (n=5) or frozen gypsy moth larvae (n=4) had no abortions due to MRLS. In, M. americanum larvae were dissected and fractionated. Statistically significant numbers of abortions occurred only in the positive control group and in association with the M. americanum exoskeleton. All abortions induced by exposure to M. americanum exhibited changes in echogenicity of fetal fluids and bacteriological findings post abortion that were consistent with MRLS. These studies support the hypothesis that ingestion of M. americanum larvae induces the MRLS-type equine abortions, and provide experimental evidence that this lepidopteran larva can cause an abortigenic disease in a vertebrate host.
Emma Despland - One of the best experts on this subject based on the ideXlab platform.
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thermal ecology and behaviour of the nomadic social forager Malacosoma disstria
Physiological Entomology, 2011Co-Authors: Melanie Mcclure, Elizabeth Cannell, Emma DesplandAbstract:The present study examines whether the nomadic social caterpillar Malacosoma disstria Hubner (Lepidoptera: Lasiocampidae) can thermoregulate despite the lack of a tent, and evaluates the role of thermoregulation in directing the colony's behaviour. The presence of a radiant heat and light source (i.e. a lamp in the laboratory experiments and the sun in the field observations) enables caterpillar colonies to increase body temperature by basking (remaining still under a heat source) and this is only effective when caterpillars cluster in groups. Body temperatures achieved when basking in a group coincide with the temperatures at which the development rate is maximal for this species. Indeed, in the laboratory experiments, the presence of a lamp results in higher growth rates, confirming that thermoregulation is an advantage to group living. When a radiant heat/light source is provided at a distance from the food in the laboratory, caterpillars behave to maximize thermal gains: colonies move away from the food to bivouac (i.e. group together and remain still on a silk mat) under the lamp, spend more time on the bivouac and cluster in a more cohesive group. Thermal needs thus influence habitat selection and colony aggregation. Malacosoma disstria relies on developing rapidly, despite low seasonal temperatures, aiming to benefit from springtime high food quality and low predation rates; however, unlike others in its genus, it does not build a tent but instead exhibits collective nomadic foraging (i.e. the whole colony moves together between temporary resting and feeding sites). In this species, collective thermoregulatory behaviour is not only possible and advantageous, but also drives much of the colony's behaviour, in large part dictating the temporal and spatial patterns of movement. These findings suggest that thermoregulation may be an important selection pressure keeping colonies together.
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collective foraging patterns of field colonies of Malacosoma disstria caterpillars
Canadian Entomologist, 2010Co-Authors: Melanie Mcclure, Emma DesplandAbstract:We monitored 12 colonies of the nomadic social caterpillar Malacosoma disstria Hubner (Lepidoptera: Lasiocampidae) on trembling aspen, Populus tremuloides Michx. (Salicaceae), under field conditions in spring 2007. We examined cohesion and synchronization of colonies and spatiotemporal activity patterns to compare foraging in the field with the results of laboratory studies and with foraging by central-place foragers. All colonies were highly cohesive; fragmentation was observed only three times. Activity was highly synchronous within colonies, with clear alternation between periods of activity and quiescence. Colonies performed 4.25 ± 0.12 (mean ± SE) activity bouts per day, and foraging was more likely to occur in the early morning than at midday. Colony activity was weakly correlated with temperature. In contrast to that of M. americanum (F.), the foraging schedule was flexible: foraging was observed at all recorded times and temperatures. Colonies searched for a new feeding site every 2.54 ± 0.37 days (mean ± SE) after a food source was depleted. Time spent at a food source decreased with colony size, and distance travelled between food sources increased with instar. Malacosoma disstria caterpillars on trembling aspen are not very selective; rather, they minimize movement, thus decreasing potential contacts with predators.
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consistent individual differences in the foraging behaviour of forest tent caterpillars Malacosoma disstria
Canadian Journal of Zoology, 2007Co-Authors: L Nemiroff, Emma DesplandAbstract:Outbreaking insects are often considered identical units despite recent work in behavioural ecology that shows repeatable differences can exist between individuals and can have important implications for individual fitness and population processes. However, although entomologists have neglected the hypothesis that differences between individuals can play an important role in the ecology of a species, it is not new. Wellington (1957. Can. J. Zool. 35: 293–323) suggested that consistent individual differences in behaviour may play a role in the population dynamics of Malacosoma (Hubner, 1820) species (Lepidoptera: Lasiocampidae). We used a novel approach to determine if individual larval Malacosoma disstria Hubner, 1820 exhibit distinct and repeatable behavioural traits. Second-instar caterpillars were placed on individual arenas for 1 h on 4 consecutive days, and the proportion of time spent walking, searching, quiescent, and eating was documented. Active and sluggish behavioural types were distinguished a...
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Ontogenetic changes in social behaviour in the forest tent caterpillar, Malacosoma disstria
Behavioral Ecology and Sociobiology, 2004Co-Authors: Emma Despland, Sara HamzehAbstract:Many animals, including gregarious caterpillars, begin life in groups and become increasingly solitary as they grow larger. These ontogenetic changes in social behaviour suggest that the costs and benefits of grouping change with increasing individual size. Forest tent caterpillar ( Malacosoma disstria ) colonies exhibit complex social behaviour during the early larval instars, using pheromone trails to move together between temporary bivouacs and feeding sites, and break up as the caterpillars grow. We demonstrate changes in individual responses to cues from conspecifics that explain changes in aggregation during caterpillar development. We used Markov chain analysis to test the influence of pheromone trails and colony-mates on an individual caterpillar’s tendency to switch between quiescence, searching, walking and spinning. Pheromone-laden silk trails increased the tendency to begin locomotion, whereas colony-mates increased switching from activity to quiescence. Trails also influenced the form taken by locomotor behaviour, and promoted directed walking over searching. Social cues thus increase the efficiency of individual locomotion. Younger larvae were more quiescent and more reluctant to walk in the absence of trails than were older insects. An increase in independent locomotion as the larvae grow provides a mechanism to explain colony break-up and points to an ontogenetic shift in the internal processes driving behaviour. Scaling relationships suggest that many of the benefits associated with group-living in caterpillars decrease as individuals grow larger, providing an adaptive explanation for observed ontogenetic changes in social behaviour.
Robert Progar - One of the best experts on this subject based on the ideXlab platform.
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Nuclear polyhedrosis virus as a biological control agent for Malacosoma americanum (Lepidoptera: Lasiocampidae)
2016Co-Authors: Robert Progar, M. J. Rinella, D. Fekedulegn, L ButlerAbstract:Eastern tent caterpillar [Malacosoma americanum (F.)] is a defoliator of trees and shrubs. Caterpillar popula-tions cycle over an 8–10 year period (Meyers 1990) and occasionally become so large that trees may b
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Malacosoma americanum (Lepidoptera: Lasiocampidae)
2010Co-Authors: M. J. Rinella, D. Fekedulegn, Robert Progar, L ButlerAbstract:Nuclear polyhedrosis virus as a biological control agent for Malacosoma americanum (Lepidoptera: Lasiocampidae
