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Trichostrongylid nematodes can cause serious loss in the livestock economy; nevertheless, infections with these ubiquitous nematodes in animals from developing countries are largely neglected. The present paper provides a systematic review and meta-analysis to evaluate the status of trichostrongyle infections in domestic ruminants from Egypt. Out of 626 collected publications, 118 were defined suitable for inclusion in this review and represented trichostrongyle infections in 5 ruminant species (sheep, goats, cattle, buffaloes and camels) from Egypt. Published surveys have mostly focused on sheep, which had the highest (44.8%) pooled prevalence of trichostrongyle infections based on 95% confidence interval (35.9-53.6%) with no significant variations among sheep in different Egyptian regions. Goats had lower infection prevalence (31.2%, 21.5-40.8%) in comparison to sheep, and no significant regional differences were also found. The management and marketing practices likely account for the wide distribution of infection among small ruminants across Egypt. Variable trichostrongyle infection rates were estimated for camels (38.8%, 28.9-48.7%), cattle (27.4%, 14.4-40.3%) and buffaloes (12.2%, 8.0-16.4%). The prevalence of infection was significantly high during winter (52.1%, 32.2-72.1%), which provide favorable conditions for development and survival of larvae on pastures. The most common trichostrongyle identified in infected animals was Haemonchus contortus. The parasite was detected in 38.8% (29.9-47.6%) of infected sheep, 35.3% (24.8-45.7%) of infected goats and in 40.6% (18.6-62.5%) of infected camels. Clinical infections have been reported in a limited number of studies. Analysis of fecal egg counts (FECs) revealed that more than half (52.7%, 30.4-75.0%) of the tested sheep had low counts (<500 eggs per gram EPG), whereas only a few sheep (6.1%, 3.5-8.7%) had high counts >2000 EPG, implying that subclinical infections are common; however, the clinical infections cannot be completely ruled out. Anthelmintic resistance does not appear to be serious in trichostrongyle populations infecting ruminants from Egypt; nonetheless there have been a few cases of albendazole resistance in trichostrongyles infecting sheep. This paper contributes to a better understanding of the epidemiology and economic implications of trichostrongyle infections in ruminants from Egypt, which is crucial for establishing effective control strategies against these ubiquitous nematodes., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Background: West Nile virus (WNV), a global arbovirus, is the most prevalent mosquito-transmitted infection in the United States. Forecasts of WNV risk during the upcoming transmission season could provide the basis for targeted mosquito control and disease prevention efforts. We developed the Arbovirus Mapping and Prediction (ArboMAP) WNV forecasting system and used it in South Dakota from 2016 to 2019. This study reports a post hoc forecast validation and model comparison., Objectives: Our objective was to validate historical predictions of WNV cases with independent data that were not used for model calibration. We tested the hypothesis that predictive models based on mosquito surveillance data combined with meteorological variables were more accurate than models based on mosquito or meteorological data alone., Methods: The ArboMAP system incorporated models that predicted the weekly probability of observing one or more human WNV cases in each county. We compared alternative models with different predictors including a ) a baseline model based only on historical WNV cases, b ) mosquito models based on seasonal patterns of infection rates, c ) environmental models based on lagged meteorological variables, including temperature and vapor pressure deficit, d ) combined models with mosquito infection rates and lagged meteorological variables, and e ) ensembles of two or more combined models. During the WNV season, models were calibrated using data from previous years and weekly predictions were made using data from the current year. Forecasts were compared with observed cases to calculate the area under the receiver operating characteristic curve (AUC) and other metrics of spatial and temporal prediction error., Results: Mosquito and environmental models outperformed the baseline model that included county-level averages and seasonal trends of WNV cases. Combined models were more accurate than models based only on meteorological or mosquito infection variables. The most accurate model was a simple ensemble mean of the two best combined models. Forecast accuracy increased rapidly from early June through early July and was stable thereafter, with a maximum AUC of 0.85. The model predictions captured the seasonal pattern of WNV as well as year-to-year variation in case numbers and the geographic pattern of cases., Discussion: The predictions reached maximum accuracy early enough in the WNV season to allow public health responses before the peak of human cases in August. This early warning is necessary because other indicators of WNV risk, including early reports of human cases and mosquito abundance, are poor predictors of case numbers later in the season. https://doi.org/10.1289/EHP10287.

Trichostrongyle nematodes can be a major threat to the profitability of small ruminant producers depending of the species and intensity of trichostrongyles parasitizing their herd. Haemonchus contortus, Teladorsagia circumcincta, and Trichostrongylus colubriformis are typically the most common and clinically important species. Three lectins (PNA, LCA and AAL) have been reported to bind specifically to eggs from these three genera and therefore could be used to quantify the intensity of each species in individual animals. Peanut agglutinin (PNA) has been the most commonly tested lectin because it selectively binds intensely to eggs of the most pathogenic species, H. contortus. Lens culinaris agglutinin (LCA) and Aleuria aurantia agglutinin (AAL) have shown specificity to T. circumcincta and Trichostrongylus spp. respectively, however, these lectins have only been evaluated using eggs harvested directly from adult females, and not from fecal samples. The purpose of the present study is to describe a method to sequentially stain H. contortus, T. circumcincta and Trichostrongylus spp. fecal eggs with PNA, LCA and AAL, and then evaluate the resultant staining patterns seen with eggs collected from a naturally infected goat shown with PCR to contain H. contortus, T. circumcincta, Ostertagia leptospicularis, Trichostrongylus colubriformis and Trichostrongylus axei eggs. These results were also compared with patterns observed with eggs stained with single lectins and double combinations of lectins. The various patterns were then compared to those seen with egg samples collected from an ewe shown to only contain H. contortus. PNA bound intensely and uniformly to all eggs from samples containing only H. contortus eggs; however, some eggs additionally bound LCA and AAL in localized patches of varying size, and a few eggs exhibited intense and uniform binding of all three lectins. Single PNA-staining of goat samples containing the five trichostrongyles species identified most eggs as H. contortus, and triple-staining showed patterns consistent with those seen for H. contortus. Binding of AAL to non-Haemonchus eggs was uniform but showed significant variations in intensity. Lesser staining eggs tended to also stain intensely with LCA, which is consistent with published binding pattern for T. circumcincta. Most eggs that AAL bound intensely to did not bind with LCA, which is consistent with published binding pattern for Trichostrongylus spp. Autofluorescence was observed with the DAPI filter-cube among most non-Haemonchus eggs. This study demonstrates the need for additional field studies to further validate the specificity of these three lectins for use in identifying eggs from the three species of trichostrongyles., (Copyright © 2021. Published by Elsevier B.V.)

Mosquito surveillance has been conducted across South Dakota (SD) to record and track potential West Nile virus (WNV) vectors since 2004. During this time, communities from 29 counties collected nearly 5.5 million mosquitoes, providing data from over 60,000 unique trapping nights. The nuisance mosquito, Aedes vexans (Meigen) was the most abundant species in the state (39.9%), and most abundant in most regions. The WNV vector, Culex tarsalis Coquillett (Diptera: Culicidae), was the second most abundant species (20.5%), and 26 times more abundant than the other Culex species that also transmit WNV. However, geographic variation did exist between WNV vector species, as well as relative abundance of vector and nuisance mosquitoes. The abundance of Ae. vexans decreased from east to west in South Dakota, resulting in an increase in the relative abundance of Cx. tarsalis. Other species are reported in this study, with various relative abundances throughout the different regions of South Dakota. WNV infection rates of mosquitoes showed that Cx. tarsalis had the most positive sampling pools and the highest vector index of all the species tested. This study addressed the need for an updated summary of the predominant mosquito species present in the United States Northern Great Plain and provides infection rate data for WNV among these predominant species., (© The Author(s) 2019. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Parasite species infecting cattle throughout northern North American are generally the same as those found throughout North America. Throughout Canada, cattle are primarily infected with Ostertagia ostertagi and Cooperia oncophora, whose larvae survive cold winters within soil of pastures. Overwintering larvae of these species maintain a temporary population of refugia available in spring to grazing cattle. Cattle from northern United States are also infected with Cooperia punctata and Haemonchus placei, whose larvae cannot survive cold winters within pastures. Anthelmintics with persistent activity are used during spring to recover some of these losses; however, anthelmintic resistance limits effectiveness of this strategy., Competing Interests: Disclosure This review was supported by South Dakota State University Agricultural Experiment Station., (Copyright © 2019 Elsevier Inc. All rights reserved.)

Intestinal sub-epithelial myofibroblasts (ISEMFs) are mesenchymal cells that do not express cytokeratin but express α-smooth muscle actin and vimentin. Despite being cells with diverse functions, there is a paucity of knowledge about their origin and functions primarily due to the absence of a stable cell line. Although myofibroblast in vitro models for human, mouse, and pig are available, there is no ISEMF cell line available from young calves. We isolated and developed an ileal ISEMF cell line from a 2-d-old calf that expressed α-smooth muscle actin and vimentin but no cytokeratin indicating true myofibroblast cells. To overcome replicative senescence, we immortalized primary cells with SV40 large T antigen. We characterized and compared both primary and immortalized ileal ISEMF cells for surface glycan and Toll-like-receptor (TLR) expression by lectin-binding assay and real-time quantitative PCR (RT-qPCR) assay respectively. SV40 immortalization significantly decreased surface lectin binding for lectins GSL-I, PHA-L, ECL, Jacalin, Con-A, LCA, and LEL. Both cell types expressed TLRs 1-9 and showed no significant differences in TLR expression. Thus, these cells can be useful in vitro model to study ISEMF's origin, physiology, and functions.

Trichostrongylid nematodes are a common cause of gastroenteritis in sheep. Despite its worldwide distribution, Teladorsagia circumcincta has not been included in reports listing the various trichostrongyles infecting sheep from Egypt. Herein, we describe the presence of 2 T. circumcincta haplotypes infecting small ruminants from Egypt. For this study, fresh fecal samples were collected from 340 sheep and 115 goats reared at 5 districts in Dakahlia governorate and its surroundings, Egypt. Trichostrongyle eggs were harvested from the samples, and then subjected to DNA isolation and analysis. Polymerase chain reaction (PCR) amplification was carried out for the second internal transcribed spacer of ribosomal DNA ( ITS2 rDNA ). Purified PCR products of T. circumcincta were sequenced, and the revealed sequences were subjected to the nucleotide and phylogenetic analysis. A relatively high prevalence of trichostrongyles eggs was identified in sheep (33.2%) and a lower prevalence was found in goats (14.7%). Molecular analysis revealed, for the first time, 2 sheep herds from Egypt that were infected with T. circumcincta . Both infected herds were raised by the Bedouins in rural areas of El Mahalla El Kubra city. No T. circumcincta infections were found in any of the goats. Nucleotide sequence analysis revealed 2 haplotypes (Te1 and Te2) from 7 successfully sequenced samples (5 from the first and 2 from the second herd). Te1 was the major haplotype in both herds, and Te2 was retrieved from a single sample. Phylogenetic analysis displayed that the Te1 haplotype clustered with one from Cyprus, which might have been introduced to Egypt via goats imported from Cyprus due to a program to improve meat and milk production in Egypt. The present results could be beneficial in understanding the epidemiology of T. circumcincta and other trichostrongyles in Egypt, and have implementations in the effective control strategies used in this region.

The intestinal epithelium is a major site of interaction with pathogens. In bovine intestinal epithelial cells (BIECs), Toll-like receptors (TLRs) play an important role in innate immune responses against enteric pathogens. This study is aimed at establishing a stable bovine intestinal epithelial cell line that can be maintained by a continuous passage so that studies on innate immune responses against various enteric pathogens can be performed. The main goal was to establish pure cultures of primary and immortalized bovine intestinal epithelial cells from the ileum and then characterize them biochemically and immunologically. Mixed epithelial and fibroblast bovine ileal intestinal cultures were first established from a 2-day old calf. Limiting dilution method was used to obtain a clone of epithelial cells which was characterized using immunocytochemistry (ICC). The selected clone BIEC-c4 was cytokeratin positive and expressed low levels of vimentin, confirming the epithelial cell phenotype. Early passage BIEC-c4 cells were transfected with either simian virus 40 (SV40) large T antigen or human telomerase reverse transcriptase (hTERT), or human papillomavirus (HPV) type 16E6/E7 genes to establish three immortalized BIEC cell lines. The expression of SV40, hTERT and HPV E6/E7 genes in immortalized BIECs was confirmed by a polymerase chain reaction (PCR). Immunocytochemistry and immunofluorescence assays also confirmed the expression of SV40, hTERT and HPV E6 proteins. The immortalized BIECs were cytokeratin positive and all except HPV-BIECs expressed low levels of vimentin. A growth kinetics study indicated that there were no significant differences in the doubling time of immortalized BIECs as compared to early passage BIEC-c4 cells. All four BIEC types expressed TLR 1-10 genes, with TLR 3 and 4 showing higher expression across all cell types. These newly established early passage and immortalized BIEC cell lines should serve as a good model for studying infectivity, pathogenesis and innate immune responses against enteric pathogens.

Influenza viruses are a group of respiratory pathogens that have evolved into four different types: A, B, C, and D. A common feature is that all four types are capable of replicating and transmitting among pigs. Here, we describe the development of isogenous cell culture system from the swine respiratory tract to study influenza viruses. Phenotypic characterization of swine primary nasal turbinate, trachea and lung cells revealed high expression of cytokeratin and demonstrated tissue site dependent expression of tight junction proteins. Furthermore, lectin binding assay on these cells demonstrated higher levels of Sia2-6Gal than Sia2-3Gal receptors and supported the replication of influenza A, B, C, and D viruses to appreciable levels at both 33 and 37 °C, but replication competence was dependent on virus type or temperature used. Overall, these swine primary respiratory cells showed epithelial phenotype, which is suitable for studying the comparative biology and pathobiology of influenza viruses., (Copyright © 2018 Elsevier Inc. All rights reserved.)

Models that forecast the timing and location of human arboviral disease have the potential to make mosquito control and disease prevention more effective. A common approach is to use statistical time-series models that predict disease cases as lagged functions of environmental variables. However, the simplifying assumptions required for standard modeling approaches may not capture important aspects of complex, non-linear transmission cycles. Here, we compared a set of alternative models of human West Nile virus (WNV) in 2004-2017 in South Dakota, USA. We used county-level logistic regressions to model historical human case data as functions of distributed lag summaries of air temperature and several moisture indices. We tested two variations of the standard model in which 1) the distributed lag functions were allowed to change over the transmission season, so that dependence on past meteorological conditions was time varying rather than static, and 2) an additional predictor was included that quantified the mosquito infection growth rate estimated from mosquito surveillance data. The best-fitting model included temperature and vapor pressure deficit as meteorological predictors, and also incorporated time-varying lags and the mosquito infection growth rate. The time-varying lags helped to predict the seasonal pattern of WNV cases, whereas the mosquito infection growth rate improved the prediction of year-to-year variability in WNV risk. These relatively simple and practical enhancements may be particularly helpful for developing data-driven time series models for use in arbovirus forecasting applications., (Copyright © 2018 Elsevier B.V. All rights reserved.)

In 2016, we compared susceptibility to the insecticide, permethrin, between the West Nile virus vector, Culex tarsalis Coquillett, and a major nuisance mosquito, Aedes vexans (Meigen), using baseline diagnostic dose and time values determined using the CDC bottle bioassay protocol. Mosquitoes were collected in the wild in Brookings County, South Dakota, situated in the Northern Great Plains of the USA. The determined diagnostic dose and time were then used in 2017 to validate these measurements for the same 2 mosquito species, collected at a second location within Brookings County. The diagnostic dose was determined for multiple time periods and ranged from 27.0 µ g/ml at 60 min to 38.4 µ g/ml at 30 min. There was no significant difference detected in mortality rates between Cx. tarsalis and Ae. vexans for any diagnostic time and dose. For practical purposes, mosquitoes in 2017 were tested at 38 µ g/ml for 30 min; expected mortality rates were 93.38% for Cx. tarsalis and 94.93% for Ae. vexans. Actual 2017 mortality rates were 92.68% for Cx. tarsalis and 96.12% for Ae. vexans , validating the usefulness of this baseline at an additional location and year.

Introduction: Predicting the timing and locations of future mosquito-borne disease outbreaks has the potential to improve the targeting of mosquito control and disease prevention efforts. Here, we present and evaluate prospective forecasts made prior to and during the 2016 West Nile virus (WNV) season in South Dakota, a hotspot for human WNV transmission in the United States., Methods: We used a county-level logistic regression model to predict the weekly probability of human WNV case occurrence as a function of temperature, precipitation, and an index of mosquito infection status. The model was specified and fitted using historical data from 2004-2015 and was applied in 2016 to make short-term forecasts of human WNV cases in the upcoming week as well as whole-year forecasts of WNV cases throughout the entire transmission season. These predictions were evaluated at the end of the 2016 WNV season by comparing them with spatial and temporal patterns of the human cases that occurred., Results: There was an outbreak of WNV in 2016, with a total of 167 human cases compared to only 40 in 2015. Model results were generally accurate, with an AUC of 0.856 for short-term predictions. Early-season temperature data were sufficient to predict an earlier-than-normal start to the WNV season and an above-average number of cases, but underestimated the overall case burden. Model predictions improved throughout the season as more mosquito infection data were obtained, and by the end of July the model provided a close estimate of the overall magnitude of the outbreak., Conclusions: An integrated model that included meteorological variables as well as a mosquito infection index as predictor variables accurately predicted the resurgence of WNV in South Dakota in 2016. Key areas for future research include refining the model to improve predictive skill and developing strategies to link forecasts with specific mosquito control and disease prevention activities.

North American bison (Bison bison) producers face many challenges, including the potential clinical and economics problems caused by trichostrongyle nematodes within their herds. Little is known about the prevalence, intensity, geographical distribution and clinical significance of these parasites in commercial bison herds, even from regions where bison production has become popular. This study involved a large herd of bison from eastern South Dakota that was experiencing clinical parasitism due to a temporary over-stocking problem. After documenting fecal egg counts (FECs) and trichostrongyle genera present among the 3 main age-categories (i.e. adults, yearlings, calves) of bison during this heavily infected grazing season, the effects of doramectin treatment on the different age groups was also evaluated. This is the first bison study using PCR to identify genera of trichostrongyles in fecal samples. Virtually all 103 bison fecal samples from all 3 age classes were shedding trichostrongyle eggs by the end of the season, and the mean FECs were 34 eggs/g (EPG) among the cows, 125 EPG in the yearlings, and 186 EGP among calves. Based upon this heavily-infected herd, there is evidence that the susceptibility of bison to trichostrongyles is more similar to beef cattle than to sheep. Other parasites such as Moniezia, Nematodirus, Trichuris, and coccidians were also identified in these samples. All but 3 of the 51 samples analyzed with PCR shown at least 1 trichostrongyle genera. Ostertagia was detected in 68.6% of the samples, Cooperia in 80.39%, Haemonchus in at least 73% and Trichostrongylus in 16% of the herd. Most commonly, bison were infected with combinations of Haemonchus/Ostertagia/Cooperia. After treatment with doramectin, the mean FECs dropped by 99.9% for all of the bison age classes., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Filamentous cyanobacteria are currently being engineered to produce long-chain organic compounds, including 3rd generation biofuels. Because of their filamentous morphology, standard methods to quantify viability (e.g., plate counts) are not possible. This study investigated a dual-fluorescence assay based upon the LIVE/DEAD® BacLight™ Bacterial Viability Kit to quantify the percent viability of filamentous cyanobacteria using a microplate reader in a high throughput 96-well plate format. The manufacturer's protocol calls for an optical density normalization step to equalize the numbers of viable and non-viable cells used to generate calibration curves. Unfortunately, the isopropanol treatment used to generate non-viable cells released a blue pigment that altered absorbance readings of the non-viable cell solution, resulting in an inaccurate calibration curve. Thus we omitted this optical density normalization step, and carefully divided cell cultures into two equal fractions before the isopropanol treatment. While the resulting calibration curves had relatively high correlation coefficients, their use in various experiments resulted in viability estimates ranging from below 0% to far above 100%. We traced this to the apparent inaccuracy of the propidium iodide (PI) dye that was to stain only non-viable cells. Through further analysis via microplate reader, as well as confocal and wide-field epi-fluorescence microscopy, we observed non-specific binding of PI in viable filamentous cyanobacteria. While PI will not work for filamentous cyanobacteria, it is possible that other fluorochrome dyes could be used to selectively stain non-viable cells. This will be essential in future studies for screening mutants and optimizing photobioreactor system performance for filamentous cyanobacteria., (Copyright © 2015 Elsevier B.V. All rights reserved.)

An egg hatch assay (EHA) and a larval migration assay (LMA) involving Haemonchus contortus was used to evaluate the anthelmintic activity of methanol extracts from 40 plants that are native or naturalized within the U.S.A. Northern Great Plains. Only one of these 40 plants (i.e. Lotus corniculatus) had been previously evaluated for activity against any gastrointestinal nematode. The various extracts were initially screened at 50mg/ml diluted either in 0.5% dimethyl sulphoxide (DMSO) or 3-(N-morpholino) propanesulfonic acid (MOPS buffer), and plants showing 100% inhibition at 50mg/ml, were further evaluated at 8 other concentrations (25-0.19 mg/ml). Extracts with 100% activity with the EHA were again screened with the LMA (50mg/ml). Two extracts with the highest LMA inhibition were also evaluated at lower concentrations (25-3.1mg/ml). Of the 40 methanolic extracts screened, 7 (Chrysothamnus viscidiflorus, Ericameria nauseosa, Liatris punctata, Melilotus alba, Melilotus officinalis, Perideridia gairdneri, and Sanguinaria canadensis) showed significant egg-hatch inhibition in DMSO and MOPS buffer. Three extracts (Geranium viscosissimum, L. corniculatus, and Rhus aromatica) only showed significant inhibition in DMSO. The 8 extracts showing 100% efficacy at 50mg/ml exhibited dose-dependent effects at the 8 lower concentrations, and R. aromatica and E. nauseosa extracts had the lowest ED50 values. Similarly, when these 8 plant extracts were further evaluated with the LMA, the extracts of E. nauseosa and R. aromatica again exhibited the highest activity (p<0.001), with ED50 values of 4.0mg/ml and 10.43 mg/ml respectively. Three other extracts (C. viscidiflorus, M. alba and M. officinalis) also showed inhibitory activity in the LMA. These results support the need for additional evaluations of the nematocidal properties for at least these 5 plants., (Copyright © 2014. Published by Elsevier B.V.)

Despite a cold temperate climate and low human population density, the Northern Great Plains has become a persistent hot spot for human West Nile virus (WNV) disease in North America. Understanding the spatial and temporal patterns of WNV can provide insights into the epidemiological and ecological factors that influence disease emergence and persistence. We analyzed the 1,962 cases of human WNV disease that occurred in South Dakota from 2002-2012 to identify the geographic distribution, seasonal cycles, and interannual variability of disease risk. The geographic and seasonal patterns of WNV have changed since the invasion and initial epidemic in 2002-2003, with cases shifting toward the eastern portion of South Dakota and occurring earlier in the transmission season in more recent years. WNV cases were temporally autocorrelated at lags of up to six weeks and early season cumulative case numbers were correlated with seasonal totals, indicating the possibility of using these data for short-term early detection of outbreaks. Epidemiological data are likely to be most effective for early warning of WNV virus outbreaks if they are integrated with entomological surveillance and environmental monitoring to leverage the strengths and minimize the weaknesses of each information source.

Haemonchus contortus infections have been increasingly reported in ungulates from cold climates even though past studies have shown that the free-living juveniles from this species survive poorly under freezing conditions. Overwintering strategies of H. contortus have not been documented in the Unites States Northern Great Plains. A PCR survey identified H. contortus as vastly predominant trichostrongyle species present (in addition to occasional detections of Teladorsagia sp.) in a closed farm flock of sheep from Brookings County, SD. Benzimidazole (BZ) and avermectin (AV) anthelmintics had been used intensely for many years on this flock. During the autumn season, three fecal egg count reduction tests (doramectin, albendazole, and moxidectin) were performed over a 4 year span to assess drug effectiveness within the flock. Significant drug resistance was found in Haemonchus adults with doramectin (69% efficacy), marginal resistance was found with albendazole (90% efficacy) and no resistance was found in moxidectin (100% efficacy). The following spring, pre-lambing and post-lambing fecals were obtained from albendazole and moxidectin treatment years to assess the resistance of the tissue-dwelling fourth-stage juveniles (J4s) at those times. Albendazole treated pre-lambing fecals averaged only 4 EPG and treated post-lambing fecals increased to 454 EPG, indicating that many of the J4s were not killed during the autumn treatment. Moxidectin pre-lambing fecals averaged only 1 EPG, and post-lambing fecals only increased to 6 EPG in the treated moxidectin population and 1422 EPG in the untreated moxidectin population. In addition to evaluating the ability of H. contortus to overwinter as drug resistant tissue-dwelling J4s, this study also evaluated the overwintering ability of pasture-dwelling, free-living third-stage juveniles at this farm. In the summers of 2010 and 2011, naïve tracer lambs were placed on a H. contortus contaminated pasture for 3 weeks to assess J3 winter survival. In 2010, tracer lambs only averaged 7 EPG whereas drylotted control lambs averaged 2 EPG; in 2011, tracer lambs averaged 2 EPG while the control lambs averaged 1 EPG. These results suggest that at this northern plains farm, yearly transmission of H. contortus is predominately through drug-resistant J4s. This is consistent with other cold-climate, overwintering studies involving H. contortus from Europe., (Published by Elsevier B.V.)

α-Santalol is active component of sandalwood oil and has been shown to have chemopreventive effects against chemically and UVB-induced skin cancer development in mice. α-Santalol is also shown to have skin permeation enhancing effects. Honokiol and magnolol isolated from Magnolia officinalis bark extract have also been shown to have chemopreventive effects against chemically and UVB-induced skin cancer in mice. This study was conducted to investigate the combination effects of α-santalol, honokiol and magnolol to study any additive/synergistic effects to lower the doses required for chemoprevention. Pretreatment of combinations of α-santalol with honokiol and magnolol significantly decreased tumor multiplicity upto 75% than control, α-santalol, honokiol and magnolol alone in SKH-1 mice. Combination of α-santalol with honokiol and magnolol also decreased cell viability, proliferation, and enhanced apotosis in comparison to α-santalol, honokiol and magnolol alone in Human epidrmoid carcinoma A431 cells. Overall, the results of present study indicated combinations of α-santalol with honokiol and magnolol could provide chemoprevention of skin cancer at lower doses than given alone.

Environmental variability has important influences on mosquito life cycles and understanding the spatial and temporal patterns of mosquito populations is critical for mosquito control and vector-borne disease prevention. Meteorological data used for model-based predictions of mosquito abundance and life cycle dynamics are typically acquired from ground-based weather stations; however, data availability and completeness are often limited by sparse networks and resource availability. In contrast, environmental measurements from satellite remote sensing are more spatially continuous and can be retrieved automatically. This study compared environmental measurements from the NASA Advanced Microwave Scanning Radiometer on EOS (AMSR-E) and in situ weather station data to examine their ability to predict the abundance of two important mosquito species (Aedes vexans and Culex tarsalis) in Sioux Falls, South Dakota, USA from 2005 to 2010. The AMSR-E land parameters included daily surface water inundation fraction, surface air temperature, soil moisture, and microwave vegetation opacity. The AMSR-E derived models had better fits and higher forecasting accuracy than models based on weather station data despite the relatively coarse (25-km) spatial resolution of the satellite data. In the AMSR-E models, air temperature and surface water fraction were the best predictors of Aedes vexans, whereas air temperature and vegetation opacity were the best predictors of Cx. tarsalis abundance. The models were used to extrapolate spatial, seasonal, and interannual patterns of climatic suitability for mosquitoes across eastern South Dakota. Our findings demonstrate that environmental metrics derived from satellite passive microwave radiometry are suitable for predicting mosquito population dynamics and can potentially improve the effectiveness of mosquito-borne disease early warning systems.

Background: Magnolol, a plant lignan isolated from the bark and seed cones of Magnolia officinalis, has been shown to have chemopreventive effects on chemically-induced skin cancer development. The objectives of this investigation are to study the anticarcinogenic effects of magnolol on UVB-induced skin tumor development in SKH-1 mice, a model relevant to humans, and determine the possible role of apoptosis and cell cycle arrest involved in the skin tumor development., Methods: UVB-induced skin carcinogenesis model in SKH-1 mice was used for determining the preventive effects of magnolol on skin cancer development. Western blottings and flow cytometric analysis were used to study the effects of magnolol on apoptosis and cell cycle., Results: Magnolol pretreated groups (30, 60 μ g) before UVB treatments (30 mJ/cm2, 5 days/week) resulted in 27-55% reduction in tumor multiplicity as compared to control group in SKH-1 mice. Magnolol pretreatment increased the cleavage of caspase-8 and poly-(-ADP-ribose) polymerase (PARP), increased the expression of p21, a cell cycle inhibitor, and decreased the expression of proteins involved in the G2/M phase of cell cycle in skin samples from SKH-1 mice.Treatment of A431 cells with magnolol decreased cell viability and cell proliferation in a concentration dependent manner. Magnolol induced G2/M phase cell cycle arrest in A431 cells at 12 h with a decreased expression of cell cycle proteins such as cyclin B1, cyclin A, CDK4, Cdc2 and simultaneous increase in the expression of Cip/p21, a cyclin-dependent kinase inhibitor. Magnolol induced apoptosis in vivo and in vitro with an increased cleavage of caspase-8 and PARP. Phospho-signal transducers and activators of transcription 3 (Tyr705), B-Raf, p-MEK, and p-AKT were down-regulated, whereas phosphorylation of ERK was induced by magnolol in A431 cells., Conclusions: Magnolol pretreatments prevent UVB-induced skin cancer development by enhancing apoptosis, causing cell cycle arrest at G2/M phase, and affecting various signaling pathways. Magnolol could be a potentially safe and potent anticarcinogenic agent against skin cancer.

Transmissible spongiform encephalopathies (TSE) are a group of fatal neurodegenerative diseases that affect animals as well as humans. The oldest of these diseases is Scrapie seen in sheep. Scrapie is caused by an altered form (PrP(sc)), capable of inducing "self-replication" of the normal host prion protein (PrP(c)). There is currently no universal standard for antigen retrieval when using immunohistochemistry to simultaneously stain the PrP(c) protein and other cellular markers. The use of formalin-fixed tissue creates a challenge by concealing the antigenic sites where an antibody would bind, and lengthy antigen retrieval methods must be applied in order to facilitate staining. Further complicating sheep tissue immunohistochemistry is a significant lack of commercial antibodies to sheep cell markers available in research. Here we developed a novel immunohistochemical technique using trypsin, formic acid, and hydrated autoclaving using citraconic anhydride buffer to increase sensitivity of staining for scrapie proteins and immune cell subsets. This allowed us to stain and identify cells within lymphoid tissue associated with early lymphoid pathogenesis in scrapie., (Copyright © 2011 Elsevier B.V. All rights reserved.)

This study compared the spatial and temporal patterns of Culex tarsalis Coquillett and Aedes vexans Meigen populations and examined their relationships with land cover types and climatic variability in Sioux Falls, SD. Between 24 and 30 CDC CO2-baited light traps were set annually in Sioux Falls from May to September 2005-2008. Land cover data were acquired from the 2001 National Land Cover Dataset and the percentages of selected land cover types were calculated within a 600-m buffer zone around each trap. Meteorological information was summarized from local weather stations. Cx. tarsalis exhibited stronger spatial autocorrelation than Ae. vexans. Land cover analysis indicated that Cx. tarsalis was positively correlated with grass/hay, and Ae. vexans was positively correlated with wetlands. No associations were identified between irrigation and the host-seeking population of each species. Higher temperature in the current week and 2 wk prior and higher precipitation 3-4 wk before collection of host-seeking adult mosquitoes had positive influences on Cx. tarsalis abundance. Temperature in the current week and rainfall 2-3 wk before sampling had positive influences on Ae. vexans abundance. This study revealed the different influences of weather and land cover on important mosquito species in the Northern Great Plains region, which can be used to improve local vector control strategies and West Nile virus prevention efforts.

Background: Skin cancer is the most prevalent of all cancer types and its incidence is expected to increase substantially. Chemoprevention involves the administration of chemical agents to prevent initiation, promotion and/or progression that occurs during neoplastic development. Honokiol, a plant lignan isolated from bark and seed cones of Magnolia officinalis, has been shown to have chemopreventive effects on chemically induced skin cancer development., Aim: The objective of this investigation was to study the chemopreventive effects of honokiol on UVB-induced skin tumor development in SKH-1 mice, a model relevant to humans, and to elucidate the possible role of apoptotic proteins involved in the prevention of skin tumor development., Materials and Methods: Female SKH-1 mice were divided into two groups. Group 1 received acetone (0.2 ml, topical) and Group 2 received honokiol (30 microg in 0.2 ml acetone, topical) one hour before UVB treatment. Tumor initiation and promotion were carried out by UVB radiation (30 mJ/cm(2)/day), 5 days a week for 30 weeks. Tumor counts and mouse weights were taken weekly., Results: The honokiol-pretreated group exhibited a 45% reduction in tumor multiplicity as compared to the control group. Mechanistic studies showed the possible involvement of caspase-3, caspase-8, caspase-9, poly (ADP-ribose) polymerase (PARP) and p53 activation (p<0.05) leading to the induction of DNA fragmentation and apoptosis., Conclusion: Pretreatment with honokiol, at concentrations in micrograms per application compared with milligram applications of other potential chemopreventive agents, prevents UVB-induced skin cancer development, possibly by activating proapoptotic proteins through both intrinsic and extrinsic pathways.

Sarcophine-diol (SD), one of the structural modifications of sarcophine, has shown chemopreventive effects on 12-dimethylbenz(a)anthracene-initiated and 12-O-tetradecanoylphorbol-13-acetate-promoted skin tumor development in female CD-1 mice. The objective of this study was to determine the chemopreventive effects of SD on UVB-induced skin tumor development in hairless SKH-1 mice, a model more relevant to human skin cancer, and to determine the possible mechanisms of action. Carcinogenesis was initiated and promoted by UVB radiation. Female hairless SKH-1 mice were divided into two groups having 27 mice in each group: control and SD treatment. The control group was topically treated with 100 microL acetone and SD treatment group was topically treated with SD (30 microg/100 microL in acetone) 1 hour before each UVB radiation for 32 weeks. Tumor counts were recorded on a weekly basis for 30 weeks. Effects of SD on the expression of caspases were investigated to elucidate the possible mechanism of action. The proteins from epidermal homogenates of experimental mice were used for SDS-PAGE and Western blotting using specific antibodies against caspase-3, caspase-8 and caspase-9 respectively. TUNEL assay was used for determining DNA fragmented apoptotic cells in situ. Results showed that at the end of experiment, tumor multiplicity in control and SD treatment groups was 25.8 and 16.5 tumors per mouse respectively. Furthermore, Topical treatment of SD induced DNA fragmented apoptotic cells by upgrading the expressions of cleaved caspase-3 and caspase-8. This study clearly suggested that SD could be an effective chemopreventive agent for UVB-induced skin cancer by inducing caspase dependent apoptosis.

Aim of this study was to prepare polyamine-conjugated PAMAM dendrimers and study their permeability across Caco-2 cell monolayers. Polyamines, namely, arginine and ornithine were conjugated to the amine terminals of the G4 PAMAM dendrimers by Fmoc synthesis. The apical-to-basolateral (AB) and basolateral-to-apical (BA) apparent permeability coefficients (P(app)) for the PAMAM dendrimers increased by conjugating the dendrimers with both of the polyamines. The enhancement in permeability was dependent on the dendrimer concentration and duration of incubation. The correlation between monolayer permeability and the decrease in transepithelial electrical resistance (TEER) with both the PAMAM dendrimers and the polyamine-conjugated dendrimers suggests that paracellular transport is one of the mechanisms of transport across the epithelial cells. Cytotoxicity of the polyamine-conjugated dendrimers was evaluated in Caco-2 cells by MTT (methylthiazoletetrazolium) assay. Arginine-conjugated dendrimers were slightly more toxic than PAMAM dendrimer as well as ornithine-conjugated dendrimers. Though investigations on the possible involvement of other transport mechanisms are in progress, results of the present study suggest the potential of dendrimer-polyamine conjugates as drug carriers to increase the oral absorption of drugs.

Background: The incidence of West Nile virus (WNv) has remained high in the northern Great Plains compared to the rest of the United States. However, the reasons for the sustained high risk of WNv transmission in this region have not been determined. To assess the environmental drivers of WNv in the northern Great Plains, we analyzed the county-level spatial pattern of human cases during the 2003 epidemic across a seven-state region., Methodology/principal Findings: County-level data on WNv cases were examined using spatial cluster analysis, and were used to fit statistical models with weather, climate, and land use variables as predictors. In 2003 there was a single large cluster of elevated WNv risk encompassing North Dakota, South Dakota, and Nebraska along with portions of eastern Montana and Wyoming. The relative risk of WNv remained high within the boundaries of this cluster from 2004-2007. WNv incidence during the 2003 epidemic was found to have a stronger relationship with long-term climate patterns than with annual weather in either 2002 or 2003. WNv incidence increased with mean May-July temperature and had a unimodal relationship with total May-July precipitation. WNv incidence also increased with the percentage of irrigated cropland and with the percentage of the human population living in rural areas., Conclusions/significance: The spatial pattern of WNv cases during the 2003 epidemic in the northern Great Plains was associated with both climatic gradients and land use patterns. These results were interpreted as evidence that environmental conditions across much of the northern Great Plains create a favorable ecological niche for Culex tarsalis, a particularly efficient vector of WNv. Further research is needed to determine the proximal causes of sustained WNv transmission and to enhance strategies for disease prevention.

This study evaluated potential relationships between parasite egg/oocyst outputs in cow-calf beef herds located within the United States Northern Great Plains and herd longitude and latitude. Management of study herds was typical of herds from this region. Parasite egg/oocyst counts were measured from 10 cows and 5 calves selected from each herd near the end of the traditional grazing season (October 1993). The types and numbers of eggs and oocysts recovered from both cows and spring-born calves were consistent with those described in other studies. No significant relationship between fecal egg/oocyst counts and latitude was observed in calves or cows. Monezia egg output exhibited no significant correlation with longitude for calves or cows. In cows, a significant negative correlation was detected between coccidian oocyst counts and herd longitude but not between helminth egg counts and longitude. In calves, Nematodirus, trichostrongyle and Trichuris egg output and coccidian oocyst output were all negatively correlated with longitude. This negative correlation suggests that nematode populations within the study area decreased slightly from an east to west direction.

The purpose of this study was to evaluate the practicality of using real-time PCR for quantifying feces-derived trichostrongyle eggs. Haemonchus contortus eggs were used to evaluate fecal contaminants, time after egg embryonation, and the presence of competing and non-competing DNAs as factors that might interfere with generating reproducible results during simplex and multiplex quantitative real-time PCR (QPCR). Real-time PCR results showed linear quantifiable amplification with DNA from five to 75 eggs. However, threshold cycle (C (T)) values obtained by amplification of DNA from egg numbers between 75 and 1,000 did not differ significantly. Inhibitors of QPCR were effectively removed during DNA extraction as exemplified by the absence of any improvement in C (T) values with bovine serum albumin or phytase treatments. Changes from egg embryonation could only be detected during the first 6 h. Noncompetitive DNA did not appear to impact amplification; however, in a multiplex reaction a competing trichostrongyle such as Cooperia oncophora can hinder amplification of H. contortus DNA, when present at tenfold greater amounts. This study demonstrates the usefulness of QPCR for amplification and quantification of trichostrongyle eggs, and identifies potential limitations, which may be addressed through multiplex assays or the addition of a standard: exogenous DNA target.

Despite the development of several recent PCR assays for the egg stages of various trichostrongyles, there have been no protocols described for preserving field samples for PCR without refrigeration. In this study, Lugol's iodine (LI), sodium azide (SA), and neutral buffered formalin (NBF) were evaluated using Haemonchus contortus eggs to determine their potential as a preservative for trichostrongyle egg samples to be processed with real-time PCR. When egg recovery, embryo development, and egg morphology were evaluated from fecal samples preserved with LI, NBF, and SA, there was equally good recovery and preservation for the first month. Preserved eggs were detectable for 1 month, but after 6 months, none could be recovered. When real-time PCR analysis was performed on eggs isolated from faeces preserved with LI and SA, there was no detectable inhibition compared to fresh, non-preserved eggs; however, NBF significantly inhibited amplification. The results from this study demonstrate that for PCR applications LI and SA are effective preservatives for H. contortus eggs, resulting in good preservation of morphology while allowing for uninhibited PCR.

Bacillus is commonly isolated from soils, with organisms of Bacillus cereus sensu lato being prevalent. Knowledge of the ecology of B. cereus and other Bacillus species in soil is far from complete. While the older literature favors a model of growth on soil-associated organic matter, the current paradigm is that B. cereus sensu lato germinates and grows in association with animals or plants, resulting in either symbiotic or pathogenic interactions. An in terra approach to study soil-associated bacteria is described, using filter-sterilized soil-extracted soluble organic matter (SESOM) and artificial soil microcosms (ASM) saturated with SESOM. B. cereus ATCC 14579 displayed a life cycle, with the ability to germinate, grow, and subsequently sporulate in both the liquid SESOM extract and in ASM inserted into wells in agar medium. Cells grew in liquid SESOM without separating, forming multicellular structures that coalesced to form clumps and encasing the ensuing spores in an extracellular matrix. Bacillus was able to translocate from the point of inoculation through soil microcosms as shown by the emergence of outgrowths on the surrounding agar surface. Microscopic inspection revealed bundles of parallel chains inside the soil. The motility inhibitor L-ethionine failed to suppress outgrowth, ruling out translocation by a flagellar-mediated mechanism such as swimming or swarming. Bacillus subtilis subsp. subtilis Marburg and four Bacillus isolates taken at random from soils also displayed a life cycle in SESOM and ASM and were all able to translocate through ASM, even in presence of L-ethionine. These data indicate that B. cereus is a saprophytic bacterium that is able to grow in soil and furthermore that it is adapted to translocate by employing a multicellular mode of growth.

A multiplex PCR assay for differentiating strongyle eggs from cattle has recently been described; however, the egg disruption and DNA extraction procedures, though effective, are inadequate for large studies or clinical application. The purpose of this research was to evaluate methods for disrupting trichostrongyle eggs, then assess commercial kits for extracting egg DNA using Ostertagia ostertagi as a model species. Egg disruption procedures tested included probe sonication, bath sonication, bead beating, boiling, microwaving, proteinase K/SDS digestion, freezing, and various combinations of the above with the incorporation of sodium dodecyl sulfate. These procedures were evaluated in conjunction with four commercial DNA extraction kits: DNA Stool mini kit and DNeasy Plant kit (Qiagen), Fast DNA kit (QBiogene), and the MAP extraction kit (Tetracore). Results showed that egg disruption was best accomplished with the bead beater and ceramic beads, resulting in 100% disruption within 1min. When DNA extraction was preceded by the isolation of eggs from feces, all procedures except the Fast DNA kit produced PCR-ready DNA from at least two eggs. The DNeasy Plant kit allowed consistent detection of DNA released from one egg. Due to the morphological similarities among trichostrongyle eggs in ruminants, strongyle eggs in equids, and hookworm eggs, the methods described herein may have broad application to other nematodes.

Objective: To assess the effect of subclinical, naturally acquired gastrointestinal nematode infestation on weight gain in yearling cattle kept on pasture., Design: Prospective study., Animals: 799 Bos taurus yearlings kept on pasture with 2,805 herd mates in eastern and central South Dakota., Procedure: 11 trials were initiated at 9 sites from 1999 through 2001. For each trial, approximately 10% of cattle in each site's pasture group were identified, weighed, and administered a bolus of ivermectin (sustained-release formulation) prior to turnout. A similar subgroup of nontreated control cattle was identified and weighed prior to turnout. For each trial, treated and control groups remained with the larger pasture group throughout the entire grazing season. At the end of the grazing season, weight measurements and fecal samples were obtained from all treated and control cattle; average daily grazing gain was calculated and compared between these 2 groups., Results: Treatment of grazing cattle with ivermectin increased average daily gain by 0.0459 +/- 0.01 kg/head/d (mean +/- SEM; 0.1 +/- 0.02 lb/head/d), compared with that achieved in control cattle. Control cattle had significantly greater fecal egg counts at grazing season end than treated cattle., Conclusions and Clinical Relevance: Compared with anthelmintic-treated cattle, yearling cattle with naturally occurring gastrointestinal nematode infestations kept on pasture in the US Northern Plains had a decreased average daily gain equivalent to 6.6 kg (14.5 lb) less gain in a 143-day grazing season. Strategies for control of nematode populations in pastures should be considered to ameliorate this production loss.

Galectins are an evolutionarily conserved family of 15 different lectins found in various combinations in virtually every type of animal cell. One of the primary galectins expressed in intestinal epithelium is galectin-4, a tandem-repeat galectin with two carbohydrate-recognition domains in a single polypeptide chain. In the current study, we produced an anti-galectin-4 monoclonal antibody (MAb) for determining the distribution of galectin-4 in porcine small intestine to enhance our understanding of where galectin-4 performs its functions in the small intestine. In immunohistochemistry studies, this MAb detected galectin-4 primarily in the cytoplasm of absorptive epithelial cells lining intestinal villi. Mature epithelial cells at the villous tips stained the most intensely with this MAb, with progressively less intense staining observed along the sides of villi and into the crypts. In addition to its cytoplasmic localization, galectin-4 was also associated with nuclei in villous tip cells, indicating that some galectin-4 may migrate to the nucleus during terminal maturation of these cells. In intestinal crypts, a specific subset of cells, which may be enteroendocrine cells, expressed galectin-4 at a relatively high level. Galectin-4 distribution patterns were similar in all three regions (duodenum, jejunum, and ileum) of porcine small intestine.

Methods for killing Echinococcus multilocularis eggs within stool or intestinal samples, without damaging the diagnostic value of the sample, would significantly reduce the risk of animal health providers acquiring alveolar hydatid disease. The first objective of this study was to determine whether E. multilocularis eggs located in fox intestines can survive storage at -70 C for at least 4 days. Results showed that none of 72,000 E. multilocularis eggs remained infectious to defined strains of mice under these conditions, yet, similar eggs recovered from nonfrozen carcasses stored at 4 C for the same time period were viable. The structural identities of adult worms and eggs were not significantly altered by the freezing and thawing processes. These results indicate that ultracold temperatures can be used to kill or inactivate E. multilocularis eggs, making them safe to handle when diagnosing this parasite in definitive hosts. The second objective of this study was to determine whether E. multilocularis eggs could survive freezing to -70 C if commonly used cryopreservation protocols were used. The use of the cryoprotectant solution, 5% dimethyl sulfoxide-35% saline-60% lamb serum, with a -1 C/min freezing rate was unable to prevent the eggs from being killed by freezing to -70 C. Rapid cooling by plunge freezing into liquid nitrogen was also lethal to E. multilocularis eggs. Only a few of the many potential cryopreservation protocols were tested in this study, so it is not yet possible to completely rule out the possibility of preserving these eggs at ultralow temperatures, but it does indicate that temperatures below -70 C are lethal to eggs even under favorable storage conditions.

The main purpose of this study was to determine the effects of cortisone on the number and size of primary Echinococcus multilocularis cysts developing in a moderately resistant strain of mice, i.e., C3H/HeJ. Computerized image analysis was used to measure the surface area occupied by hydatid cysts 10 wk after inoculation of the mice with E. multilocularis eggs. Our second objective was to compare the infectivity of primary E. multilocularis hydatid cysts in C57BL/6J-Ay/a (lethal yellow) mice with that in C57BL/6J-a/a (non-agouti black) mice. The data obtained show no difference between the C3H/HeJ and C57BL/6J-a/a strains of mice; yet, the image analysis method was able to detect a slight increase in the total cyst size within the Ay/a mutant of the C57BL/6J strain. Treatment of C3H/HeJ mice with cortisone drastically increased both the number of cysts and the average size of each cyst when the treatment occurred early in the infection.

The objective of this study was to evaluate the use of a single pasture, limited treatment methodology to assess the impact of gastrointestinal nematodes on weight gain in grazing cattle. From a group of 450 British crossbred, yearling spayed heifers, 60 animals were randomly selected (prospective randomization) prior to placement on summer pasture. Each of these 60 animals was weighed, a fecal sample obtained for nematode egg count and a uniquely numbered ear tag applied. A randomly assigned group of 30 received treatment with one ivermectin sustained release bolus, while the remaining 30 served as non-treated controls. The treatment and control groups rejoined the remaining non-treated 390 animals, and were grazed as a single group for 165 days. At grazing conclusion, treatment and control cattle were individually weighed, and fecal samples obtained for nematode egg counts. Treatment was associated with a 0.064 kg per grazing day gain increase, or a 10 kg increase over the grazing season (P = 0.02). Nematode egg counts at grazing initiation were not different between treatment and control (P = 0.30), though egg counts in treated cattle at study end were lower than control (P < 0.0001). Results of this study support the use of a single pasture limited treatment approach for measuring the effect that internal nematodes have on weight gain in grazing cattle under commercial range conditions.

The strobilocercus stage of the cat tapeworm Taenia taeniaeformis is surrounded by a single syncytial sheet of cytoplasm called the tegument. The outer membrane of the tegument covers both the scolex/strobila (S/S) and the bladder portions of the strobilocercus, but only the S/S region is resistant to intestinal digestion. It has been suggested that the glycocalyx, the surface-exposed glycoconjugates of the outer membrane, may serve to insulate underlying surface membrane components from digestion. In this study, we used lectin binding to test the hypothesis that the glycocalyx of the S/S is different from that of the bladder and that this may serve as the resistance mechanism of the S/S to digestion. Biotin-labeled lectins and an avidin-glucose oxidase detection system were applied to whole strobilocerci and to 1-microm epon-araldite plastic-embedded sections. Lectins bound to either both regions of the strobilocerci, to the S/S regions only, or did not bind at all. The restriction of some glycoconjugates to the glycocalyx of the S/S region only is consistent with our hypothesis.

Echinococcus multilocularis causes a rare but potentially lethal zoonotic disease in humans. This tapeworm has been known to be endemic in foxes (Vulpes vulpes) and coyotes (Canis latrans) within the northern United States since the 1960s. One purpose of this study was to provide recent data on the prevalence of E. multilocularis in foxes and coyotes from eastern South Dakota. In a survey conducted from 1987 to 1991 and involving 137 foxes and 9 coyotes from this area, 74.5% of the foxes and 4 of the coyotes were infected. To assess the possible prevalence of alveolar echinococcosis in a group at presumptive high risk, we also conducted a serological survey of members of the South Dakota Trappers Association in 1990 and 1991. Serum samples from 115 trappers were evaluated for the presence of E. multilocularis antibodies using enzyme-linked immunosorbent assay tests involving a purified antigen called Em2, a crude E. multilocularis antigen, and a recombinant E. multilocularis antigen called II/3-10. None of the trappers showed antibody evidence for the presence of E. multilocularis. Roughly half of the surveyed individuals had trapped more than 50 foxes during their life, and almost one-fourth had trapped more than 1,000 foxes.

Two new species of Eimeria were observed in the feces of captive white-tailed deer fawns, Odocoileus virginianus, from Alabama. The first new species was easily recognized because of its small size. Sporulated oocysts are spherical, average 10.2 by 10.0 microm, and lack a micropyle and oocyst residuum. Oocysts contain a polar granule and elongate-ellipsoidal sporocysts that measure 6.7 by 3.1 microm. A Stieda body is present on the sporocysts. Oocysts were observed in the feces, and gamonts and oocysts were observed in the jejunum of a month-old fawn from Minnesota that died from enteritis due to this species. Oocysts of this small species were present in 5 of the 6 white-tailed deer fawns examined. Oocysts of a second new species are ellipsoidal and average 29.5 by 24.6 microm. The oocyst encloses an oocyst residuum, polar granule, and elongate-ellipsoidal sporocysts that average 16.0 by 9.0 microm. A Stieda body and substieda body are present on the sporocysts. Oocysts of the second new species were present in 4 of the 6 white-tailed deer fawns examined. Oocysts of E. ivensae are ovoid or flask-like and average 32.0 by 20.8 microm. The oocyst wall is rough, contains a micropyle, and encloses elongate-ellipsoidal sporocysts that average 16.5 by 7.8 microm. A Stieda body is present on the sporocysts. Oocysts of E. ivensae were present in 4 of the 6 white-tailed deer fawns. Oocysts of E. odocoilei are spherical or slightly subspherical and measure 24.7 by 21.5 microm. They enclose ovoid sporocysts that average 12.7 by 8.8 microm. A Stieda and substieda body are present on the sporocyst. Oocysts of E. odocoilei were present in 4 of the 6 white-tailed deer fawns.

Objective: To evaluate effectiveness of an allicin-based product in neonatal calves inoculated with Cryptosporidium parvum., Design: Randomized controlled study., Animals: 43 neonatal calves., Procedure: Calves were inoculated with 1.5 x 10(8) or 7.5 x 10(5) C parvum oocysts within 2 days after birth. Calves were given an allicin-based product once after inoculation or daily for 7 days after inoculation or were not treated. Calves that developed diarrhea were treated by administration of the product. Fecal consistency scores and weight gains were statistically evaluated., Results: Mean daily weight gain and severity of diarrhea in calves 4 to 21 days old were unaffected by prophylactic use of the product. However, intensive prophylactic administration may have delayed onset of C parvum-induced diarrhea in calves inoculated with the lower dose of oocysts., Clinical Implications: Administration of an allicin-based product did not alter duration of C parvum-induced diarrhea or enhance weight gain in neonatal calves. However, intensive prophylactic administration of an allicin-based product may delay onset of diarrhea in calves exposed to C parvum oocysts.

The effects of tunicamycin (TM) on the uptake and incorporation of tritiated galactose into the tegumental membrane and carcass from adult Hymenolepis diminuta were examined to assess the potential usefulness of this inhibitor for studying the function of the tapeworm surface glycocalyx. Hymenolepis diminuta adults (11 days old) were preincubated for 1 hr, pulsed for 30 min with [3H]galactose and [14C]leucine, and chased for 2 hr; replicate experiments were conducted in which all media contained no TM or TM at 10 micrograms/ml. Tunicamycin significantly inhibited the incorporation of tritiated galactose into the tapeworm's carcass and 30,000-g tegumental membrane fraction. Incorporation of tritiated galactose into the tapeworm's tegumental surface membrane also was inhibited significantly when expressed relative to the incorporation of [14C]leucine. Tunicamycin did not affect the amounts of free, i.e., soluble, [3H]galactose or [14C]leucine recovered from the tapeworms not did it affect the short-term (2 min) uptake of [3H]galactose by tapeworms. Thus, the inhibitory effect of TM appears to be at the level of protein glycosylation rather than carbohydrate (galactose) transport. The data indicate that TM might be useful for producing tapeworm surface membranes with diminished carbohydrate moieties.