White Jack Research Articles

Development of Highly Efficient Universal Pneumocystis Primers and Their Application in Investigating the Prevalence and Genetic Diversity of Pneumocystis in Wild Hares and Rabbits.

Despite its ubiquitous infectivity to mammals with strong host specificity, our current knowledge about Pneumocystis has originated from studies of merely 4% of extant mammalian species. Further studies of Pneumocystis epidemiology across a broader range of animal species require the use of assays with high sensitivity and specificity. To this end, we have developed multiple universal Pneumocystis primers targeting different genetic loci with high amplification efficiency. Application of these primers to PCR investigation of Pneumocystis in free-living hares (Lepus townsendii, n = 130) and rabbits (Oryctolagus cuniculus, n = 8) in Canada revealed a prevalence of 81% (105/130) and 25% (2/8), respectively. Genotyping analysis identified five and two variants of Pneumocystis from hares and rabbits, respectively, with significant sequence divergence between the variants from hares. Based on phylogenetic analysis using nearly full-length sequences of the mitochondrial genome, nuclear rRNA operon and dihydropteroate synthase gene for the two most common variants, Pneumocystis in hares and rabbits are more closely related to each other than either are to Pneumocystis in other mammals. Furthermore, Pneumocystis in both hares and rabbits are more closely related to Pneumocystis in primates and dogs than to Pneumocystis in rodents. The high prevalence of Pneumocystis in hares (P. sp. 'townsendii') suggests its widespread transmissibility in the natural environment, similar to P. oryctolagi in rabbits. The presence of multiple distinct Pneumocystis populations in hares contrasts with the lack of apparent intra-species heterogeneity in P. oryctolagi, implying a unique evolution history of P. sp. 'townsendii' in hares.

Ratio Variation of Maltodextrin and Gum Arabic as Encapsulant on White Jack Bean Tempe Protein Concentrate

The physical and chemical properties of encapsulated substance is directly influenced by the choice of the encapsulant. Different ratios of maltodextrin (MD) and Gum Arabic (GA) produce varying material properties. Therefore, this study aimed to obtain the optimal encapsulant ratio for white jack bean tempe protein concentrate based on physical and chemical characteristics. To achieve this, a descriptive method was employed along with One-Way ANOVA. The results showed that varying encapsulant ratio led to distinct protein content, moisture content, encapsulation efficiency, and yield. The treatment with maltodextrin and Gum Arabic ratio of 20:80 showed the highest effectiveness, with protein content, moisture content, encapsulation efficiency, and yield at 26.10 ± 0.45%, 7.93 ± 0.42%, 95.84 ± 0.71%, and 14.27%, respectively.

Potential of White Jack Bean (Canavalia ensiformis L. DC) Kefir as a Microencapsulated Antioxidant.

Oxidative stress plays a major role in the pathogenesis and progression of noncommunicable diseases. Kefir is a fermented food that has been reported to repress oxidative stress. This study aimed to assess the antioxidant activity, bioactive composition, and encapsulation efficiency of white jack bean (WJB) kefir. The following procedures were conducted: WJB was prepared and converted into juice using water solvent. The sterilized WJB juice was then fermented with kefir grain (10%) for 24∼72 h. Every 24 h, the kefir was evaluated for antioxidant activity, and the dominant bioactive component suspected to be the source of the antioxidant activity was identified. The final stage was the encapsulation process. WJB kefir showed high antioxidant activity, inhibiting DPPH radicals by 90.51±4.73% and ABTS radicals by 86.63±2.34% after 72 h of fermentation. WJB kefir contained 0.35±0.01 mg GAE/g total phenolics and 0.08 mg/g total flavonoids. The LC/MS identification suggested that the bioactive antioxidant components of the WJB kefir were from the alkaloid, saponin, phenolic, and flavonoid groups. The encapsulation with maltodextrin using freeze drying resulted in microencapsulation of WJB kefir with a particle size of 6.42±0.13 μm. The encapsulation efficiency was 79.61%, and the IC50 value was 32.62 ppm. The encapsulation method was able to maintain the antioxidant stability of the kefir and extend its shelf life. WJB kefir, a nondairy, lactose-free kefir, can be used as an antioxidant functional food.

Panorama actual de la pesca ribereña en la desembocadura del río Actopan, Chachalacas, Veracruz (periodo 2014-2023)

Currently, human activities such as tourism, human settlements, agricultural and industrial activities have generated an alteration of the biological communities associated with the coastal zone, particularly fish communities. The coastal zones of the State of Veracruz in the Gulf of Mexico are characterized by their high biodiversity and include a great variety of fishery resources, occupying fourth place in national fish production. However, there are no recent records on the ichthyofauna of the area of Chachalacas, Veracruz. In the present study, 12 samplings were carried out from February 2014 to March 2023 at the mouth of the Actopan River in both the marine and brackish water zones. Twenty species were recorded, highlighting the white jack mackerel (Carax latus), snook (Centropomus undecimalis), ocellated croaker (Sciaenops ocellatus) and mullet (Mugil liza), as frequent species, in all sampling periods, being the latter. The mullet is the only species that has remained relatively constant in terms of the abundance of organisms caught, in contrast to the white jack mackerel, which has reduced its abundance in the area. In addition, in relation to the cpue, there is a constant decrease over the years. The results of this study will help lay the groundwork for designing management plans for fishery resources in the area of Chachalacas, Veracruz. Key words: Ichthyofauna, Biodiversity, Fishing, Veracruz, CPUE

The evolution of white-tailed jackrabbit camouflage in response to past and future seasonal climates

The genetic basis of adaptive traits has rarely been used to predict future vulnerability of populations to climate change. We show that light versus dark seasonal pelage in white-tailed jackrabbits (Lepus townsendii) tracks snow cover and is primarily determined by genetic variation at endothelin receptor type B (EDNRB), corin serine peptidase (CORIN), and agouti signaling protein (ASIP). Winter color variation was associated with deeply divergent alleles at these genes, reflecting selection on both ancestral and introgressed variation. Forecasted reductions in snow cover are likely to induce widespread camouflage mismatch. However, simulated populations with variation for darker winter pelage are predicted to adapt rapidly, providing a trait-based genetic framework to facilitate evolutionary rescue. These discoveries demonstrate how the genetic basis of climate change adaptation can inform conservation.

Decadal trends in a population of urban white-tailed jackrabbits at the northern edge of its range

Decadal trends in a population of urban white-tailed jackrabbits at the northern edge of its range

WHITE-TAILED JACKRABBITS: A REVIEW AND CALL FOR RESEARCH

White-tailed jackrabbits (Lepus townsendii) were once abundant in North America and provided a number of ecosystem services such as seed dispersal, nutrient cycling, facilitating the persistence of other species, and serving as a prey species for predators, including golden eagles (Aquila chrysaetos), bobcats (Lynx rufus), and numerous others. Reports describe declines and extirpations across much of their range, but given the extremely limited research available, it is difficult to determine what factors have led to reductions of white-tailed jackrabbits. Researchers have investigated few areas of white-tailed jackrabbit ecology, including the possible effects of climate change, habitat degradation and loss, competition with black-tailed jackrabbits (Lepus californicus), and changes in predator composition. We review the life history and research available on white-tailed jackrabbits, discuss possible causes of their decline, suggest areas that require additional research, and make recommendations regarding their management.

Formulasi food bars berbahan baku koro pedang putih (Canavalia ensiformis) autoclaving - cooling

White jackbean is type of bean that grows in tropical and subtropical areas. White jackbean has large protein and complex carbohydrate content. The autoclaving - cooling process can be used to change starch into resistant starch in the white jackbe an flour through gelatinization and retrogradation processes. White jackbean flour treated with autoclaving – cooling process can be used as a raw material for the formulation of food bars. Currently food bars have been in great demand along with the needs to consume healthy and nutritious ready-to-eat food. This study aims to determine the appropriate formulation of white jack bean flour treated with autoclaving – cooling process to produce food bars with the best physical, chemical and organoleptic properties.The results showed that the best formulation is the formulation of white jackbean flour : wheat flour = 60 : 40 with 48.81% carbohydrate content, 14.87% protein content, 16.57% fat content, 17.07% moisture content, 2.68% ash content, 2269.3 gf breaking strength, 6.43 N texture, 79.59 color (L), 15.71 color (a), 17.21 color (b), 4.02 color organoleptic, 3.88 flavor organoleptic, 3.83 aroma organoleptic, 3.83 texture organoleptic. and 11,38% resistant starch content.

A Review of the Ongoing Decline of the White-Tailed Jackrabbit

The distribution and abundance of the white-tailed jackrabbit Lepus townsendii have declined significantly since 1950, continuing a trend that began in some regions of its range in the late 1800s. We reviewed museum records and the literature to evaluate the status of the white-tailed jackrabbit in each state and province in its historical range and evaluated possible reasons for its decline. Our evaluation revealed its extirpation or decline throughout much of its range, but its legal or conservation status does generally not reflect this precarious status. We note its extirpation in Missouri, Kansas and Oklahoma, and potential extirpation in British Columbia, Oregon, Illinois, and Wisconsin. We classified the white-tailed jackrabbit to be broadly extirpated in Iowa, Minnesota, Washington, Nebraska and California, and declining with local extirpations in Wyoming, Nevada, Utah, Colorado, New Mexico, and South Dakota. We consider it to be a relict in Ontario, and possibly declining in Alberta, Saskatchewan, North Dakota, Idaho, and Montana. We consider only Manitoba to have a possibly stable population. Determining the reasons for the species' reduced distribution is difficult, as the decline appears to be due to multiple factors, none of which provide a universal explanation. We dismissed road kills, recreational hunting, disease and parasites, and competition with black-tailed jackrabbits Lepus californicus as causes of the widespread population declines and extirpations. We concluded that habitat alterations and climate change are overriding factors, and that past depredation measures and increased predator populations have likely contributed to the decline. These hypotheses require further testing. We recommend more research on the distribution, abundance, ecology, and population dynamics of white-tailed jackrabbits, and management that includes a frank appraisal of the species' status, the potential for grassland restoration, and programs to reintroduce populations into prairie preserves and restored grasslands.

A Review of the Ongoing Decline of the White-Tailed Jackrabbit

Abstract The distribution and abundance of the white-tailed jackrabbit Lepus townsendii have declined significantly since 1950, continuing a trend that began in some regions of its range in the late 1800s. We reviewed museum records and the literature to evaluate the status of the white-tailed jackrabbit in each state and province in its historical range and evaluated possible reasons for its decline. Our evaluation revealed its extirpation or decline throughout much of its range, but its legal or conservation status does generally not reflect this precarious status. We note its extirpation in Missouri, Kansas and Oklahoma, and potential extirpation in British Columbia, Oregon, Illinois, and Wisconsin. We classified the white-tailed jackrabbit to be broadly extirpated in Iowa, Minnesota, Washington, Nebraska and California, and declining with local extirpations in Wyoming, Nevada, Utah, Colorado, New Mexico, and South Dakota. We consider it to be a relict in Ontario, and possibly declining in Alberta, Saskatchewan, North Dakota, Idaho, and Montana. We consider only Manitoba to have a possibly stable population. Determining the reasons for the species' reduced distribution is difficult, as the decline appears to be due to multiple factors, none of which provide a universal explanation. We dismissed road kills, recreational hunting, disease and parasites, and competition with black-tailed jackrabbits Lepus californicus as causes of the widespread population declines and extirpations. We concluded that habitat alterations and climate change are overriding factors, and that past depredation measures and increased predator populations have likely contributed to the decline. These hypotheses require further testing. We recommend more research on the distribution, abundance, ecology, and population dynamics of white-tailed jackrabbits, and management that includes a frank appraisal of the species' status, the potential for grassland restoration, and programs to reintroduce populations into prairie preserves and restored grasslands.

Changes of Complex Carbohydrates of White Jack Bean (Canavalia Ensiformis) During Autoclaving-Cooling Cycles

The extraction of white jack bean (Canavalia ensiformis) protein isolate frequently leaves a lot of precipitates containing complex carbohydrates such as starch, dietary fiber, and resistant starch. Repeated autoclaving – cooling cycles can increase the content of soluble fiber and resistant starch. The aim of this study was to determine changes of dietary fiber and resistant starch content of complex carbohydrates of white jack bean during autoclaving-cooling cycles and characterization of its chemical composition and functional properties. The experiment was conducted by applying the autoclaving process at 121oC for 15 minutes followed by cooling at 4oC for 24 hours up to 5 times. Sample was taken from each cycle of autoclaving – cooling. The best treatment was the sample with the highest total soluble fiber and resistant starch content. The best sample will be determined its chemical composition and functional properties. This study used a one-way analysis of variance to subject the data according to Completely Randomized Design. Duncan’s Multiple Range Test was applied to determine significant differences among 5 treatment means at the 5% significance level. The highest value of total soluble fiber and resistant starch content was obtained from autoclaving-cooling cycles of 3 times. The treatment increased the soluble fiber and resistant starch by 14.37% and 18.34%, respectively, but decreased 14.41% insoluble fiber. The complex carbohydrates of white jack bean treated with autoclaving-cooling cycles of 3 times had chemical composition: 10.68% moisture content, 0.92% ash content, 0.02% fat content, 1.85% protein content, 97.20% carbohydrate content (by difference), 68.42% starch content, and 14.90 ppm HCN. It also had functional properties: 351.67% WHC, 115.67% OHC, 775.33% SC, 84.63 meq/kg CEC. The conclusion was the white jack bean carbohydrate complex treated with 3 times autoclaving-cooling cycles was the best treatment to produce the highest value of total soluble fiber and resistant starch content. We suggest to examine another autoclaving temperature and cooling time to compare the result.

Black-Tailed and White-Tailed Jackrabbits in the American West: History, Ecology, Ecological Significance, and Survey Methods

Abstract. Across the western United States, Leporidae are the most important prey item in the diet of Golden Eagles (Aquila chrysaetos). Leporids inhabiting the western United States include black-tailed (Lepus californicus) and white-tailed jackrabbits (Lepus townsendii) and various species of cottontail rabbit (Sylvilagus spp.). Jackrabbits (Lepus spp.) are particularly important components of the ecological and economic landscape of western North America because their abundance influences the reproductive success and population trends of predators such as coyotes (Canis latrans), bobcats (Lynx rufus), and a number of raptor species. Here, we review literature pertaining to black-tailed and white-tailed jackrabbits comprising over 170 published journal articles, notes, technical reports, conference proceedings, academic theses and dissertations, and other sources dating from the late 19th century to the present. Our goal is to present information to assist those in research and management, particularly ...

Integrating Recent Land Cover Mapping Efforts to Update the National Gap Analysis Program's Species Habitat Map

Abstract. Over the past decade, great progress has been made to develop national extent land cover mapping products to address natural resource issues. One of the core products of the GAP Program is range-wide species distribution models for nearly 2000 terrestrial vertebrate species in the U.S. We rely on deductive modeling of habitat affinities using these products to create models of habitat availability. That approach requires that we have a thematically rich and ecologically meaningful map legend to support the modeling effort. In this work, we tested the integration of the Multi-Resolution Landscape Characterization Consortium's National Land Cover Database 2011 and LANDFIRE's Disturbance Products to update the 2001 National GAP Vegetation Dataset to reflect 2011 conditions. The revised product can then be used to update the species models. We tested the update approach in three geographic areas (Northeast, Southeast, and Interior Northwest). We used the NLCD product to identify areas where the cover type mapped in 2011 was different from what was in the 2001 land cover map. We used Google Earth and ArcGIS base maps as reference imagery in order to label areas identified as "changed" to the appropriate class from our map legend. Areas mapped as urban or water in the 2011 NLCD map that were mapped differently in the 2001 GAP map were accepted without further validation and recoded to the corresponding GAP class. We used LANDFIRE's Disturbance products to identify changes that are the result of recent disturbance and to inform the reassignment of areas to their updated thematic label. We ran species habitat models for three species including Lewis's Woodpecker (Melanerpes lewis) and the White-tailed Jack Rabbit (Lepus townsendii) and Brown Headed nuthatch (Sitta pusilla). For each of three vertebrate species we found important differences in the amount and location of suitable habitat between the 2001 and 2011 habitat maps. Specifically, Brown headed nuthatch habitat in 2011 was −14% of the 2001 modeled habitat, whereas Lewis's Woodpecker increased by 4%. The white-tailed jack rabbit (Lepus townsendii) had a net change of −1% (11% decline, 10% gain). For that species we found the updates related to opening of forest due to burning and regenerating shrubs following harvest to be the locally important main transitions. In the Southeast updates related to timber management and urbanization are locally important.

Distribution and Population Density of Jackrabbits in South Dakota

Distribution of white-tailed jackrabbit ( Lepus townsendii ) and black-tailed jackrabbit ( L. californicus ) populations have been thought to be shifting throughout the Northern Great Plains. Anecdotal reports of population declines of white-tailed jackrabbits in recent years have created concern for wildlife managers. We established 21 spotlight line transects (64.4 km) across South Dakota to evaluate jackrabbit distribution as well as to facilitate future survey efforts. We conducted surveys during 2004 and 2005 to obtain baseline information about jackrabbit distribution and population density throughout the state. We observed white-tailed jackrabbits throughout the state, and estimated the highest population density in the northwestern part of the state and lowest in east-central South Dakota. We only observed black-tailed jackrabbits at very low densities in south-central South Dakota in Tripp and Gregory Counties.

The hidden history of the snowshoe hare, Lepus americanus: extensive mitochondrial DNA introgression inferred from multilocus genetic variation.

Hybridization drives the evolutionary trajectory of many species or local populations, and assessing the geographic extent and genetic impact of interspecific gene flow may provide invaluable clues to understand population divergence or the adaptive relevance of admixture. In North America, hares (Lepus spp.) are key species for ecosystem dynamics and their evolutionary history may have been affected by hybridization. Here we reconstructed the speciation history of the three most widespread hares in North America - the snowshoe hare (Lepus americanus), the white-tailed jackrabbit (L. townsendii) and the black-tailed jackrabbit (L. californicus) - by analysing sequence variation at eight nuclear markers and one mitochondrial DNA (mtDNA) locus (6240 bp; 94 specimens). A multilocus-multispecies coalescent-based phylogeny suggests that L. americanus diverged ~2.7 Ma and that L. californicus and L. townsendii split more recently (~1.2 Ma). Within L. americanus, a deep history of cryptic divergence (~2.0 Ma) was inferred, which coincides with major speciation events in other North American species. While the isolation-with-migration model suggested that nuclear gene flow was generally rare or absent among species or major genetic groups, coalescent simulations of mtDNA divergence revealed historical mtDNA introgression from L. californicus into the Pacific Northwest populations of L. americanus. This finding marks a history of past reticulation between these species, which may have affected other parts of the genome and influence the adaptive potential of hares during climate change.

NUTRIENT UPTAKE AND USE EFFICIENCY BY TROPICAL LEGUME COVER CROPS AT VARYING PH OF AN OXISOL

Oxisols comprise large soil group in tropical America. These soils are acidic and have low fertility. Use of tropical legume cover crops in cropping systems is an important strategy to improve fertility of these soils for sustainable crop production. Data are limited on nutrient uptake and use efficiency of tropical cover crops under different acidity levels. The objective of our study was to evaluate growth and nutrient uptake parameters of sixteen tropical legume cover crops under three soil pH (5.1, 6.5, and 7.0) of an Oxisol. Shoot dry weight was influenced significantly by pH and cover crop treatments and their interactions, indicating that cover crops used had differential responses to changing soil pH levels. Overall, shoot dry weight decreased when soil pH was raised from 5.1 to 7.0, indicating acidity tolerance of cover crops. Nutrient concentration (content per unit of dry weight), uptake (concentration X dry weight), and nutrient use efficiency (dry weight of shoot per unit of nutrient uptake) varied significantly among cover crops. The variation in nutrient uptake and use efficiency among cover crop species was associated with variation in shoot dry matter production. Significant variation among crop species in dry matter production and low C/N ratios (average value of 14.25) suggest that cover crops which produced higher dry matter yield like white jack bean, gray mucuna bean, black mucuna bean, mucuna bean ana, and lablab are important choices for planting in tropical soils to recover large amount of macro and micronutrients, and to prevent such nutrient leaching in soil plant systems.

Soil Phosphorous Influence on Growth and Nutrition of Tropical Legume Cover Crops in Acidic Soil

In tropical regions, use of cover crops in crop production is an important strategy in maintaining sustainability of cropping systems. Phosphorus (P) deficiency in tropical soils is one of the most yield-limiting factors for successful production of cover crops. A greenhouse experiment was conducted to evaluate influence of P on growth and nutrient uptake in 14 tropical cover crops. The soil used in the experiment was an Oxisol, and P levels used were low (0 mg P kg−1), medium (100 mg P kg−1) and high (200 mg P kg−1). There was a significant influence of P and cover crop treatments on plant growth parameters. Phosphorus X cover crops interaction for shoot dry weight, root dry weight and root length was significant, indicating different responses of cover crops to variable P levels. Based on shoot dry weight efficiency index (SDEI), legume species were classified into efficient, moderately efficient or inefficient groups. Overall, white jack bean, gray mucuna bean, mucuna bean ana and black mucuna bean were most P efficient. Remaining species were inefficient in P utilization. Macro- and micronutrient concentrations (content per unit dry weight of tops) as well as uptakes (concentration x dry weight of tops) were significantly (P < 0.01) influenced by P as well as crop species treatments, except magnesium (Mg) and zinc (Zn) concentrations. The P x crop species interactions were significant for concentration and uptake of all the macro and micronutrients analyzed in the plant tissues, indicating concentrations and uptake of some nutrients increased while others decreased with increasing P levels. Hence, there was an antagonistic as well as synergetic effect of P on uptake of nutrients. However, uptake of all the macro and micronutrients increased with increasing P levels, indicating increase in dry weight of crop species with increasing P levels. Overall, nutrient concentration and uptake in the top of crop species were in the order of nitrogen (N) > potassium (K) > calcium (Ca) > Mg > sulfur (S) > P for macronutrients and iron (Fe) > manganese (Mn) > zinc (Zn) > copper (Cu) for micronutrients. Interspecific differences in shoot and root growth and nutrient uptake were observed at varying soil P levels

Serum lipid profile of hyperlipidemic rabbits (Lepus townsendii) treated with leaf extracts of Hibiscus rose-sinesis, Emilia coccinea, Acanthus montanus and Asystasia gangetica

There are efforts directed towards the search for medicinal plants capable of ameliorating hyperlipidemia. The present study sought to investigate the capacity of ethanolic leaf extracts of Hibiscus rose-sinesis, Emilia coccinea, Acanthus montanus and Asystasia gangetica to ameliorate hyperlipidemia in animal model. Hyperlipidemia was induced by placing experimental animals on lipogenic diet containing 2.5% cholesterol, 20% sunflower oil and 0.5% sodium cholate. Separate leaf extracts of the four plants (dose = 400 mg/kg) were administered to various groups of the experimental animals by intra peritoneal injection at regular time intervals of 12 h for 14 days. At the end of treatment, blood samples of the rabbits were measured for total cholesterol (TC), triacylglycerol (TAG), low-density lipoprotein cholesterol (LDL-C) and high-density lipoprotein cholesterol (HDL-C) concentrations. Generally, treatment of hyperlipidemic rabbits (HyL-Rs) with the four plant extracts caused different levels of lowered serum lipid components with concomitant elevation of HDL-C concentration. Specifically, the capacities of the four plant extracts to reduce serum levels of TC in the experimental animals were in the order: H. rose-sinesis > A. montanus > A. gangetica > E. coccinea. In addition, serum lipid profile (SLP) of HyL-Rs treated with extract of H. rose-sinesis was comparable with the control groups. The present study showed that the tendency but varied capacities of the four experimental plant extracts to alter SLP of HyL-Rs were associated with their phytochemical peculiarities, which suggested that certain phytochemicals exhibit hypolipidemic activity in vivo. Key words: Serum lipid profile, Hibiscus rose-sinesis, Emilia coccinea, Acanthus montanus and Asystasia gangetica.

Urban White-tailed Jackrabbits (&lt;em&gt;Lepus townsendii&lt;/em&gt;) Eat Spike Plants (&lt;em&gt;Cordyline australis&lt;/em&gt;) in Winter

We observed White-tailed Jackrabbits (Lepus townsendii) eating spike plants (Cordyline australis), a non-native ornamental garden plant, in our front yard within the city of Edmonton, Alberta. We have noted this persistent behaviour every winter between 2006-2007 and 2011-2012. By late January, the plants were usually eaten right down to the stem base. We suggest that the White-tailed Jackrabbits turn to this food source in winter when more preferred foods are lacking, are in short supply, or are not as readily accessible. Our observations add another plant species to the list of non-native plants consumed by White-tailed Jackrabbits.

Ectoparasites of rabbits and hares in Manitoba, Canada, with observations on age-specific dispersal in Haemodipsus setoni (Phthiraptera: Anoplura: Polyplacidae)

AbstractDuring 1994–2008, 58 adult and 195 juvenile eastern cottontail rabbits (Sylvilagus floridanus (Allen)), one adult and 23 juvenile snowshoe hares (Lepus americanus Erxleben), and eight adult white-tailed jackrabbits (Lepus townsendii Bachman) (Mammalia: Leporidae) were examined for ectoparasites. The most abundant ectoparasite on cottontails was the sucking louse, Haemodipsus setoni Ewing (Phthiraptera; Polyplacidae), recorded from this host for the first time. Infestations in adult and juvenile cottontails were highly aggregated, k = 0.136 and 0.153, respectively. Prevalence of infestation in adult cottontails was 70.6%, with a mean intensity of 5614.1 (range: 1–166 249); 10 adults had more than 1000 lice. In juvenile cottontails, prevalence was 34.8% and mean intensity was 6.2 (range: 1–87). On adult cottontails, 73.4% of the total lice were nymphs, while on juvenile cottontails only 11.6% were nymphs. It appears that dispersal from parents to offspring is overwhelmingly achieved by adult lice. Seventeen adult cottontails were infested with the tick, Haemaphysalis leporispalustris (Packard) (Acari: Ixodidae). No fleas specific to rabbits were collected but small numbers of the rodent fleas Monopsyllus vison (Baker), Orchopeas caedens (Jordan), and Aetheca wagneri (Baker) (Siphonaptera: Ceratophyllidae) were recorded. Only one snowshoe hare was infested with H. setoni and three were infested with H. leporispalustris; no fleas were found on snowshoe hares. Two white-tailed jackrabbits were infested with H. leporispalustris; one carried Pulex irritans Linnaeus (Siphonaptera: Pulicidae), and none carried lice.