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The annual abundance of chewing lice (Phthiraptera) was recorded on great horned owls (Bubo virginianus (Gmelin), Aves: Strigidae) from 1994 to 2015 in Manitoba, Canada. Kurodaia magna Emerson (Amblycera: Menoponidae) had a mean annual abundance about half that for Strigiphilus oculatus (Rudow) (Ischnocera: Philopteridae). Mean intensity, rather than prevalence, explained the variation in annual abundance. Temporal variation (measured as population variability) in abundance and mean intensity were high and similar (0.62–0.67), but lower for nymph to female ratio (0.36–0.38). Temporal variation of prevalence and sex ratio were higher for K. magna (0.34–0.35) than for S. oculatus (0.21–0.22), and typical for other louse species. The high temporal variability for abundance and mean intensity suggest lower year-to-year stability than exhibited by other chewing lice, but over 80% of this variability was due to sampling error resulting from small sample sizes in some years and extreme intensities in the aggregated distributions of intensity. The remaining variation, < 20%, revealed no significant differences in annual abundance or mean intensity among years, and therefore stable populations over 22 years. Populations of 12 species of chewing lice show lower temporal variability and therefore greater stability than three other insect taxa.
Specimens (n = 508) of eight species of owl (Aves: Strigiformes) collected from 1994 to 2017 in Manitoba, Canada, were weighed and examined for chewing lice (Phthiraptera: Amblycera, Ischnocera). The relationship between host body mass and infestation by 12 species of lice was examined. Host body mass explained 52% (P = 0.03) of the variation in mean intensity of louse infestation among hosts, due primarily to a high abundance of lice on the heaviest owl species. The relationship was due to the mean intensity of lice, and neither species richness nor the prevalence of lice was related to host body mass. For individual louse species, the relationship was due primarily to Kurodaia acadicae Price and Beer, Kurodaia magna Emerson, and an undetermined species of Kurodaia Uchida (Phthiraptera: Menoponidae) (R2 = 0.997), but not the nine Strigiphilus Mjöberg (Phthiraptera: Philopteridae) species (R2 = 0.27). Louse intensity did not increase with body size for individual birds of any of the owl species. Mean intensity is expected to increase in proportion with the size, specifically the surface area, of the host. Why that relationship holds only for one louse genus, and not for the most abundant genus of lice on owls, and weakly compared with other families of birds, has yet to be determined.
Eleven of the 12 species of owls (Aves: Strigidae, Tytonidae) known to occur in Manitoba, Canada, were examined for chewing lice (Phthiraptera: Amblycera, Ischnocera) from 1976 to 2015: barn owl (Tyto alba (Scopoli); Aves: Tytonidae) (n = 2), snowy owl (Bubo scandiacus (Linnaeus); Aves: Strigidae) (n = 77), great horned owl (Bubo virginianus (Gmelin); Aves: Strigidae) (n = 262), great grey owl (Strix nebulosa Förster; Aves: Strigidae) (n = 142), barred owl (Strix varia Barton; Aves: Strigidae) (n = 10), northern hawk owl (Surnia ulula (Linnaeus); Aves: Strigidae) (n = 18), short-eared owl (Asio flammeus (Pontoppidan); Aves: Strigidae) (n = 74), long-eared owl (Asio otus (Linnaeus); Aves: Strigidae) (n = 67), eastern screech owl (Megascops aslo (Linnaeus); Aves: Strigidae) (n = 59), boreal owl (Aegolius funereus (Linnaeus); Aves: Strigidae) (n = 47), and northern saw-whet owl (Aegolius acadicus (Gmelin); Aves: Strigidae) (n = 44), a total of 802 owls. No lice were found infesting barn owl (Tyto alba (Scopoli); Aves: Tytonidae) or eastern screech owl (Megascops asio (Linnaeus); Aves: Strigidae). We collected a total of 113 810 lice of 12 species: Kurodaia Uchida (Phthiraptera: Menoponidae) – three species; and Strigiphilus Mjöberg (Phthiraptera: Philopteridae) – nine species. Overall prevalence of infestation ranged from 10.0% to 88.9%. Mean intensity for total lice ranged from 22.4 to 506.5. Infestation parameters for each louse–host combination are provided; prevalence and mean intensity were not related for louse–host species combinations. Distribution of louse infestations was highly aggregated. In all louse–host combinations but one, either females were more prevalent than males or there was no significant deviation from 50:50. Male Strigiphilus ceblebrachys Denny significantly outnumbered females in snowy owls. There was a tendency for louse species to co-occur on the same host specimen. Where sample sizes for owls were large enough, no seasonal patterns in abundance of lice were detected.
OBJECTIVES/SPECIFIC AIMS: In an effort to elucidate the role of potentially cancer chemopreventive drugs, we leveraged the Mayo Clinic-Karolinska Institute collaboration to create a multidisciplinary team that included an epidemiologist, statisticians, and physicians. We performed a population-based cohort study to examine the association between low dose aspirin, non-aspirin NSAIDs, statins, metformin, other risk factors and the risk of biliary tract cancer (BTC), while assessing confounding by sex. METHODS/STUDY POPULATION: We conducted a nationwide Swedish population-based cohort study using the Swedish Prescribed Drug Registry, which virtually completely enumerates use of prescribed medications nationwide since 2005. BTC diagnosis (intrahepatic cholangiocarcinoma [iCCA], extrahepatic cholangiocarcinoma [eCCA] or gallbladder cancer [GBC]) was ascertained from the Swedish Cancer Registry. Age-scaled Cox models, with exposure as time-varying covariates, were used to calculate hazard ratios (HRs), separately for men and women. RESULTS/ANTICIPATED RESULTS: In the 5.7 million person cohort, the risk of iCCA was significantly lower in men using statins (HR 0.62,95%CI 0.39-1.00, p = 0.05), with a non-significant reduction in women. Statin use was associated with a significantly decreased risk of eCCA in both women (HR 0.60,0.38-0.94, p = 0.03) and men (HR 0.47,0.28-0.80, p = 0.01). Low dose aspirin (HR 0.76,0.60-0.97, p = 0.03) was associated with a lower risk of GBC only in women, while statins (HR 0.72,0.55-0.93, p = 0.01) showed a significantly decreased risk of GBC in women and a non-significant reduction in men. For all BTC subtypes, combined use of low dose aspirin and statins did not confer additional risk reductions beyond those achieved by statins alone. Male and female users of non-aspirin NSAIDs appeared to be at increased risk of BTC and its subtypes. Metformin did not significantly affect risk of BTC. DISCUSSION/SIGNIFICANCE OF IMPACT: Our collaborative efforts allowed us to develop the largest population-based cohort evaluating risk and protective factors for BTC. Our results provide strong evidence in favor of the chemopreventive roles of low dose aspirin and statins in a subtype- and sex-specific manner. Individual risk factors contribute to development of BTC subtypes in different magnitudes. The next steps to translate these findings into clinical practice require randomized clinical trials that validate our results and provide a more complete picture of the risk-benefit ratio.
Absorbed residue studies have been used in subsistence research for decades. Only more recently have the chemical methods employed been used to explore the consumption of ritual concoctions such as those including cacao, yaupon holly, and alcohol. In this article we use mass spectrometry to identify Datura residues in prehistoric contexts from western Mexico and the American Southeast. Datura is a genus of flowering plants that contain hallucinogenic alkaloids. Their use in both regions is known historically and still continues today. This study sampled 55 pottery vessels and 18 shell vessels using both a traditional burr method and a water-based sonicator sampling method. Datura residues were found in 13 pottery vessels and 14 shell vessels using both sampling approaches. These results demonstrate that it is possible to identify Datura residue in pottery and shell vessels and that the use of Datura extends back into prehistory in both regions. The form and decoration of pottery vessels with Datura residues show correlations with specific motifs and themes. Historically, shell vessels were used in the Southeast for the consumption of another ritual beverage, called the Black Drink. The presence of Datura shows that those vessels were used for other kinds of beverages as well.
Strain rates are fundamental measures of ice flow and are used in a wide variety of glaciological applications including investigations of bed properties, calculations of basal mass balance on ice shelves, and constraints on ice rheological models. However, despite their extensive application, strain rates are calculated using a variety of methods and length scales and the details are often not specified. In this study, we compare the results of nominal and logarithmic strain-rate calculations based on a satellite-derived velocity field of the Antarctic ice sheet generated from Landsat 8 satellite data. Our comparison highlights the differences between the two common approaches in the glaciological literature. We evaluate the errors introduced by each approach and their impacts on the results. We also demonstrate the importance of choosing and specifying a length scale over which strain-rate calculations are made, which can strongly influence other derived quantities such as basal mass balance on ice shelves. Finally, we present strain-rate data products calculated using an approximate viscous length-scale with satellite observations of ice velocity for the Antarctic continent.
The annual abundance of chewing lice (Phthiraptera) was recorded from 1996 to 2015 in Manitoba, Canada, on two species of woodpeckers (Piciformes: Picidae). Yellow-bellied sapsuckers (Sphyrapicus varius (Linnaeus)) were infested with Menacanthus pici (Denny) (Amblycera: Menoponidae) and Penenirmus auritus (Scopoli) (Ischnocera: Philopteridae); northern flickers (Colaptes auratus (Linnaeus)) were also infested with M. pici, as well as two other Ischnocera, Penenirmus jungens (Kellogg) and Picicola porisma Dalgleish. The mean annual abundance varied from nine to 51 lice per bird for the four species, with prevalence, mean intensity, sex ratio, and nymphs per female also varying among louse species. Menacanthus pici populations on both hosts were unstable: abundance rose over two decades because of increasing prevalence, whereas the abundance of the other three louse species fluctuated around a mean. Population variability was similar for the lice on both hosts, with the metric, PV, ranging from 0.41 to 0.51 on a 0–1 scale, once the effect of the trend in abundance for M. pici had been removed. Although the population dynamics for species of lice on these two woodpeckers were distinct, inter-specific differences in population stability were less pronounced than observed in the few other species of bird lice studied in this way.
Specimens of five species of woodpeckers (Piciformes: Picidae) from Manitoba, Canada, were weighed and examined for chewing lice, 1998–2015: downy woodpecker (Picoides pubescens (Linnaeus), n=49), hairy woodpecker (Picoides villosus (Linnaeus), n=23), pileated woodpecker (Dryocopus pileatus (Linnaeus), n=10), northern flicker (Colaptes auratus (Linnaeus), n=170), and yellow-bellied sapsucker (Sphyrapicus varius (Linnaeus), n=239). The relationship between body mass of each host species and infestation by seven species of lice was analysed: Menacanthus pici (Denny) from all host species, Brueelia straminea (Denny) from Picoides Lacépède species, Penenirmus jungens (Kellogg) from northern flicker, Penenirmus auritus (Scopoli) from the other four hosts, Picicola porisma Dalgleish from northern flicker, Picicola snodgrassi (Kellogg) from Picoides species, and Picicola marginatulus (Harrison) from pileated woodpeckers. Mean abundance of lice increased with the mean mass of their host. Neither the species richness of lice nor the prevalence of lice were related to host body mass. Host body mass explained 98% of the variation in mean intensity of louse infestation among hosts. The positive association of mean intensity and body size was also detected for three genera of lice. Louse intensity also increased with body size for individual birds, more so for some species of lice and hosts than others. Body size matters, but the adaptations that allow higher mean intensity on larger host species remain to be determined.
Forested landscapes provide a source of micronutrient rich food for millions of people around the world. A growing evidence base suggests these foods may be of great importance to the dietary quality of people living in close proximity to forests – especially in communities with poor access to markets. Despite widespread evidence of the consumption of forest foods around the world, to date, few studies have attempted to quantify the nutritional contributions these foods make. In this study we tested the hypothesis that the consumption of forest foods can make important contributions to dietary quality. We investigated the dietary contributions of wild forest foods in smallholder dominated forested landscapes from 37 sites in 24 tropical countries, using data from the Poverty and Environment Network (PEN). We compared quantities of forest foods consumed by households with dietary recommendations and national average consumption patterns. In addition, we compared the relative importance of forests and smallholder agriculture in supplying fruits, vegetables, meat and fish for household consumption. More than half of the households in our sample collected forest foods for their own consumption, though consumption patterns were skewed towards low-quantity users. For high-quantity consuming households, however, forest foods made a substantial contributions to their diets. The top quartile of forest food users in each site obtained 14.8% of the recommended amounts of fruits and vegetables, and 106% of the reference quantity of meat and fish from forests. In 13 sites, the proportion of meat and fish coming from forests was greater than from domestic livestock and aquaculture, while in 11 sites, households procured a greater proportion of fruits and vegetables from forests than from agriculture. Given high levels of heterogeneity in forest food consumption, we identify four forest food use site typologies to characterize the different use patterns: ‘forest food dependent’, ‘limited forest food use’, ‘forest food supplementation’ and ‘specialist forest food consumer’ sites. Our results suggest that while forest foods do not universally contribute significantly to diets, in some sites where large quantities of forest foods are consumed, their contribution towards dietary adequacy is substantial.
Three species of woodpeckers (Piciformes: Picidae) in Manitoba, Canada, were examined for chewing lice (Phthiraptera): the resident downy woodpecker (Picoides pubescens (Linnaeus), n=55), and two migrants, yellow-bellied sapsucker (Sphyrapicus varius (Linnaeus), n=316) and northern flicker (Colaptes auratus (Linnaeus), n=225). Six species were collected: Menacanthus pici (Denny) (Amblycera: Menoponidae) from all hosts, and five species of Ischnocera (Philopteridae): Penenirmus auritus (Scopoli) from downy woodpeckers and sapsuckers, Picicola snodgrassi (Kellogg) and Brueelia straminea (Denny) from downy woodpeckers, and Penenirmus jungens (Kellogg) and Picicola porisma Dalgleish from flickers. Adults and nymphs were present on downy woodpeckers all year, and on migrant sapsuckers and flickers from when they arrived until they left, suggesting lice reproduce continuously on their hosts. Prevalence and mean intensities of louse infestations generally decreased from their respective springtime levels to their lowest values during or at the end of the breeding season of their hosts, and then increased in various degrees during the fall. No seasonal pattern in louse sex ratios was observed except on northern flickers, where male to female ratios for two of three species were lowest during the breeding season. Resident and migrant hosts had similar seasonal patterns of infestation by lice.
Five species of woodpeckers (Piciformes: Picidae) in Manitoba, Canada were examined for chewing lice (Phthiraptera: Amblycera and Ischnocera): downy woodpecker (DOWO) (Picoides pubescens (Linnaeus), n=56), hairy woodpecker (HAWO) (Picoides villosus (Linnaeus), n=32), pileated woodpecker (PIWO) (Dryocopus pileatus (Linnaeus), n=12), northern flicker (NOFL) (Colaptes auratus (Linnaeus), n=223), and yellow-bellied sapsucker (YBSA) (Sphyrapicus varius (Linnaeus), n=192). Seven species of lice were collected (total number=40 613): Menacanthus pici (Denny) from all species of woodpeckers, Brueelia straminea (Denny) from both species of Picoides Lacépède, Penenirmus jungens (Kellogg) from northern flicker, Penenirmus auritus (Scopoli) from all species of woodpeckers examined except northern flickers, Picicola porisma Dalgleish from northern flickers, Picicola snodgrassi (Kellogg) from both species of Picoides, and Picicola marginatulus (Harrison) from pileated woodpeckers. Prevalence for total louse infestation ranged from 32.3% to 85.7% (NOFL>YBSA>PIWO>DOWO>HAWO). Mean intensity for total lice ranged from 29.2 to 232.4 (PIWO>NOFL>HAWO>YBSA>DOWO). Infestation parameters for each louse/host combination are provided. Distribution of louse infestations was highly aggregated. In all louse/host combinations, either females were more prevalent than males or there was no significant deviation from 50:50. There was a tendency for louse species to co-occur on the same host specimen.
Populations of the chewing louse, Mulcticola macrocephalus (Kellogg) (Phthiraptera: Philopteridae), were investigated on its host the common nighthawk, Chordeiles minor (Forster) (Aves: Caprimulgiformes: Caprimulgidae), from 1992 to 2013 in southern Manitoba, Canada. The louse was present in all but one year with an annual prevalence of 0.52, mean intensity of 16 lice per infested bird, a ratio of 0.81 males and 1.89 nymphs to female (n=178). Intensity was the same in the first 11 and last nine years of the study, but prevalence dropped from 0.59 to 0.34 between the two decades. Population variability for annual abundance, measured as PV, was 0.49. In August, adults and newly fledged nighthawks had a prevalence of infestation similar to the adults that immigrated in the spring, but mean intensity did not reach spring levels until September–October. Samples of hosts were small in some years, reducing the precision of parameter estimates, particularly those based on ratios. The population parameters for M. macrocephalus on a native migrant host were intermediate in the ranges of parameters for four species of lice on non-migratory, introduced feral pigeons, Columba livia Gmelin (Aves: Columbiformes: Columbidae), but the distributions of M. macrocephalus among nighthawks was less severely aggregated than those from pigeons.
Seasonal dynamics of louse (Phthiraptera) populations on feral pigeons, Columba livia Gmelin (Aves: Columbiformes: Columbidae) were investigated from 2003 to 2012 in southern Manitoba, Canada. Pigeons were infested with: Philopteridae – Campanulotes compar (Burmeister), Columbicola columbae (Linnaeus), and Coloceras tovornikae Tendeiro; Menoponidae – Hohorstiella lata (Piaget). We consider the hypothesis that four species living on the same host show similar seasonal dynamics, coordinated by the life history of the host. Adults of both sexes and nymphs of all four species were present on pigeons throughout the year, consistent with continuous feeding and reproduction. Campanulotes compar and C. columbae populations were low in spring and peaked in September, with C. columbae showing greater seasonal changes for all population parameters. Coloceras tovornikae showed two annual peaks in abundance in spring and late summer, and H. lata was most abundant in the cold months of the year. Over 10 years, the four species showed distinct seasonal dynamics, although they live on the same birds. Seasonal patterns provided no evidence that louse reproduction or abundance is coordinated by the long breeding and moulting seasons of the host.
The Bovine Respiratory Disease Coordinated Agricultural Project (BRD CAP) is a 5-year project funded by the United States Department of Agriculture (USDA), with an overriding objective to use the tools of modern genomics to identify cattle that are less susceptible to BRD. To do this, two large genome wide association studies (GWAS) were conducted using a case:control design on preweaned Holstein dairy heifers and beef feedlot cattle. A health scoring system was used to identify BRD cases and controls. Heritability estimates for BRD susceptibility ranged from 19 to 21% in dairy calves to 29.2% in beef cattle when using numerical scores as a semi-quantitative definition of BRD. A GWAS analysis conducted on the dairy calf data showed that single nucleotide polymorphism (SNP) effects explained 20% of the variation in BRD incidence and 17–20% of the variation in clinical signs. These results represent a preliminary analysis of ongoing work to identify loci associated with BRD. Future work includes validation of the chromosomal regions and SNPs that have been identified as important for BRD susceptibility, fine mapping of chromosomes to identify causal SNPs, and integration of predictive markers for BRD susceptibility into genetic tests and national cattle genetic evaluations.
Population parameters of ectoparasites on feral pigeons, Columba livia Gmelin (Aves: Columbiformes: Columbidae), were estimated from 1995–2012 in southern Manitoba, Canada. The ectoparasites are chewing lice (Phthiraptera): Philopteridae – Campanulotes compar (Burmeister), Columbicola columbae (Linnaeus), and Coloceras tovornikae Tendeiro; Menoponidae – Hohorstiella lata (Piaget). We tested the hypotheses that both abundance and population stability are species-specific traits. Over 10 years, the four species of lice had distinct population dynamics. Campanulotes compar and C. columbae were more abundant than C. tovornikae and H. lata, had higher male to female sex ratios and higher ratios of nymphs to females, different levels of aggregation, and more stable populations. Campanulotes compar was more prevalent than C. columbae and its prevalence was more stable, and the two species also showed differences in the levels and stabilities of male and nymph to female ratios. Coloceras tovornikae had a higher prevalence and male to female sex ratio than H. lata, but the two species showed similar levels of stability for these parameters. The level of stability of these populations was relatively high compared with many other organisms, and in particular higher than for plant ectoparasites (Hemiptera: Aphididae). Although the four species occupy similar habitats, often on the same bird, and three of the four feed in a similar way, the population biology of each species is distinct. The life history traits that lead to these differences have yet to be determined.