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Resistance to the anthelmintic drug monepantel (Zolvix ® ) has emerged in parasitic worms infecting sheep and goats. The mechanism of resistance in these cases is unknown. The drug targets nicotinic acetylcholine receptors belonging to the nematode-specific DEG-3 subfamily. We examined the receptor gene, Hco-mptl-1, in a highly Zolvix ® -resistant and a -susceptible isolate of the parasitic nematode Haemonchus contortus . cDNA coding for the full length receptor protein ( Hco -MPTL-1) was present in all clones prepared from a pool of susceptible larvae (21/21 clones) and approximately 50% of those from the resistant isolate (17/33). On the other hand, the remaining clones from the resistant isolate showed various mutations that resulted in truncated predicted proteins, missing at least one transmembrane domain. The most common mutation (11/33 clones) resulted in the retention of intron 15, a premature stop codon, and a truncated protein. Sequencing of intron 15 genomic DNA showed very few SNPs in susceptible larvae and in 12/18 clones from resistant larvae, alongside the presence of at least 17 SNPs in the remaining resistant clones. The present study shows that the highly resistant isolate has a number of mutations in the drug target gene that would most-likely result in a non-functional receptor, thus rendering the larvae insensitive to the drug. The presence of many wild-type sequences in this highly-resistant population suggests that there was a significant presence of heterozygotes in the survivors of the field drench treatment from which the isolate was derived, and hence that at least some of the mutations may be dominant. Alternatively, their presence may be due to the additional influence of mutations at another locus contributing to the resistance phenotype. The presence of multiple separate mutations in the Hco-mptl-1 gene in this viable field-derived worm isolate may at least partly explain why resistance to Zolvix ® has arisen rapidly in the field. [ABSTRACT FROM AUTHOR]

This paper outlines a redevelopment plan for downtown Lubbock, Texas, titled the Urban Courtyard Project, which draws upon the courtyard traditions of Spain to restructure urban alleys into a series of interconnected courtyards. In this paper, we share graduate student projects and argue for the benefits of this economically-viable, sustainable approach to urban redevelopment. [ABSTRACT FROM AUTHOR]

Triclabendazole (TCBZ) is the only chemical that kills early immature and adult Fasciola hepatica (liver fluke) but widespread resistance to the drug greatly compromises fluke control in livestock and humans. The mode of action of TCBZ and mechanism(s) underlying parasite resistance to the drug are not known. Due to the high prevalence of TCBZ resistance (TCBZ-R), effective management of drug resistance is now critical for sustainable livestock production. Here, we discuss the current status of TCBZ-R in F. hepatica , the global distribution of resistance observed in livestock, the possible mechanism(s) of drug action, the proposed mechanisms and genetic basis of resistance, and the prospects for future control of liver fluke infections using an integrated parasite management (IPM) approach. [ABSTRACT FROM AUTHOR]

Objective To test mediating effects of positive emotion and activity restriction on the associations of resilience and pain interference with distress reported by individuals with traumatic upper limb loss evaluated for prosthetics. Design Cross-sectional correlational study of several demographic and self-report measures of resilience, pain interference, activity restriction, positive emotions, and symptoms of depression and posttraumatic stress. Setting Six regional centers throughout the United States. Participants A total of 263 prospective participants consented to be evaluated for eligibility and need for upper extremity prosthetics; participants (N=202; 57 women [28.2%] and 145 men [71.8%]; mean age, 41.81±14.83y; range, 18.01–72.95y) who sustained traumatic injuries were retained in this study. Most of them were identified as white (70.8%; n=143), followed by black (10.4%; n=21), Hispanic (9.9%; n=20), Asian (3.0%; n=6), other (1.5%; n=3), and missing (4.5%; n=9). Interventions Not applicable. Main Outcome Measures Primary Care Posttraumatic Stress Disorder Screen and depression screen. Results Resilience and pain interference were significantly correlated in predicted directions with positive emotions, activity restriction, and the 2 distress variables. A path model revealed that the associations of resilience and pain interference with both distress variables were completely mediated by positive emotions and activity restriction. There were no significant direct effects of resilience or pain interference on either distress variable. Conclusions Resilience may facilitate adjustment via beneficial and predicted associations with positive emotions and active engagement with the environment. These relations are independent of the significant and inverse associations of pain interference with these same variables. Longitudinal research is needed to understand interactions between positive emotions and activity over time in promoting adjustment after traumatic limb loss. Individuals reporting depression and/or posttraumatic stress disorder symptoms may require interventions that reduce avoidance and promote activities that may increase the likelihood of experiencing positive emotions. [ABSTRACT FROM AUTHOR]

Highlights: [•] Triclabendazole resistant F. hepatica is confirmed in infected Australian cattle. [•] Resistance was observed on four beef properties and one dairy property. [•] Live drug resistant adult flukes were recovered from cattle after treatment. [•] A coproantigen reduction test was used to identify resistance. [•] We describe a method suitable for post-treatment analysis of fluke infection. [Copyright &y& Elsevier]

Abstract: Background: Like most caregivers, informal caregivers for children (typically parents) with special needs supply the majority of the care provided. Formal care is sometimes needed to supplement informal caregivers'' efforts. For those interested in children with special needs, there is a paucity of research on those factors affecting the amount of formal care that caregivers'' request. Objectives/Hypotheses: This research investigates factors affecting the amount of Medicaid personal care services (PCS) requested by primary caregivers for children with special needs. The research focuses especially on the roles played by the child''s functional status, intellectual abilities, and behaviors in determining the level of assistance requested by caregivers. Methods: The data used in this research are cross-sectional information on 262 children with special needs who were Medicaid recipients in a single southwestern state. These data were collected in 2007 by master''s trained social workers or registered nurses using a standardized assessment instrument. Results: The results indicate that a child''s ability to independently perform activities of daily living (ADLs) tasks plays the major role in determining caregivers'' perceptions of the need for PCS. The severity of a child''s intellectual disability, like some other factors investigated, has an effect on caregivers'' perceptions, but it is an indirect effect that operates through the level of the child''s ADL impairment. A child''s age and behaviors have direct effects on caregivers'' perceptions of need, as does the presence of barriers to the caregiver providing care. Discussion: Much of the research on children with special needs has emphasized the importance of the child''s medical or behavioral diagnoses. Little attention has been given to modeling caregivers'' perceptions of children''s needs. This analysis of caregivers'' requests for formal PCS brings to the forefront the role of ADL or functional status in this process. Many factors that one would expect to directly affect caregivers'' perceptions of need, instead, have indirect effects filtered through their impact on the child''s functional status. [Copyright &y& Elsevier]

Abstract: Objective: To examine the effectiveness of an individualized problem-solving intervention provided to family caregivers of women living with severe disabilities. Design: Family caregivers were randomly assigned to an education-only control group or a problem-solving training (PST) intervention group. Participants received monthly contacts for 1year. Participants: Family caregivers (64 women, 17 men) and their care recipients (81 women with various disabilities) consented to participate. Main outcome measures: Caregivers completed the Social Problem-Solving Inventory – Revised, the Center for Epidemiological Studies Depression scale, the Satisfaction with Life scale, and a measure of health complaints at baseline and in three additional assessments throughout the year. Results: Multilevel modeling was used to conduct intent-to-treat analyses of change trajectories for each outcome variable. Caregivers who received PST reported a significant linear decrease in depression over time; no effects were observed for caregiver health or life satisfaction. Caregivers who received PST also displayed an increase in constructive problem-solving styles over the year. Conclusions: PST may benefit community-residing family caregivers of women with disabilities, and it may be effectively provided in home-based sessions that include face-to-face visits and telephone sessions. [Copyright &y& Elsevier]

Abstract: Objective: To examine the effectiveness of an individualized problem-solving intervention delivered in videoconferencing sessions with family caregivers of persons living with a spinal cord injury (SCI) and possible contagion effects on care recipients. Design: Family caregivers were randomly assigned to an education-only control group or an intervention group in which participants received problem-solving training (PST) in monthly videoconference session for a year. Participants: Sixty-one caregivers (54 women, 7 men) and their care recipients (40 men, 21 women) consented to participate. Main outcome measures: The Social Problem-Solving Inventory-Revised was administered to caregivers. Caregivers and care recipients completed the Inventory to Diagnose Depression, the SF-36 and the Satisfaction with Life scale at pre-treatment, 6 months and 12 months. Results: Twenty-eight caregivers discontinued the study and their follow-up data were unavailable at the final assessment. Older caregivers were more likely than younger caregivers to remain in the study. Intent-to-treat analyses projected a significant decrease in depression among caregivers receiving PST; efficacy analyses indicated this effect was pronounced at the 6th month assessment. ITT analyses and efficacy analyses revealed that care recipients of caregivers receiving PST reported gains in social functioning over time. Conclusions: Community-based, telehealth interventions may benefit family caregivers and their care recipients, but the mechanisms of these effects are unclear. Attrition and sample issues should be considered in future studies with these populations. [Copyright &y& Elsevier]

Abstract: Rivera PA, Elliott TR, Berry JW, Grant JS. Problem-solving training for family caregivers of persons with traumatic brain injuries: a randomized controlled trial. Objective: To test the hypothesis that a problem-solving training program would lower depression, health complaints, and burden, and increase well-being reported by community-residing family caregivers of persons with traumatic brain injuries (TBIs). Design: Randomized controlled trial. Setting: General community. Participants: Of the 180 people who expressed interest in the study, 113 did not meet eligibility criteria. A consenting sample of family caregivers were randomized into a problem-solving training group (4 men, 29 women; average age, 51.3y) or an education-only control group (34 women; average age, 50.8y). Care recipients included 26 men and 7 women in the intervention group (average age, 36.5y) and 24 men and 10 women in the control group (average age, 37.2y). Intervention: Problem-solving training based on the D''Zurilla and Nezu social problem-solving model was provided to caregivers in the intervention group in 4 in-home sessions and 8 telephone follow-up calls over the course of their year-long participation. Control group participants received written educational materials and telephone calls at set intervals throughout their 12 months of participation. Main Outcome Measures: Caregiver depression, health complaints, well-being, and social problem-solving abilities. Results: Hierarchical linear models revealed caregivers receiving problem-solving training reported significant decreases in depression, health complaints, and in dysfunctional problem-solving styles over time. No effects were observed on caregiver well-being, burden, or constructive problem-solving styles. Conclusions: Problem-solving training provided in the home appears to be effective in alleviating distress and in decreasing dysfunctional problem-solving styles among family caregivers of persons with TBI. Methodologic limitations and the implications for interventions and future research are discussed. [Copyright &y& Elsevier]

Abstract: Grant JS, Elliott TR, Weaver M, Glandon GL, Raper JL, Giger JN. Social support, social problem-solving abilities, and adjustment of family caregivers of stroke survivors. Objective: To determine contributions of social support and social problem-solving abilities in prediction of adjustment of family caregivers of stroke survivors. Design: Descriptive. Setting: Two rehabilitation facilities (1 private, 1 state) in the southeastern United States. Participants: Fifty-two family caregivers (46 women, 6 men) of stroke survivors (28 women, 24 men). Interventions: Not applicable. Main Outcome Measures: Predictor variables were social support and social problem-solving abilities. Outcome measures of caregiver adjustment were depressive symptomatology, well-being, and general health. Participants completed these measures 1 to 2 days before discharge from inpatient rehabilitation and at 5, 9, and 13 weeks postdischarge in the home. Results: Trajectory analysis indicated higher levels of social support were associated with lower levels of caregiver depressive symptomatology and higher levels of well-being and general health, independent of social problem solving. A greater negative problem orientation was associated with higher levels of depressive symptomatology and lower levels of well-being. A more positive problem orientation was associated with greater increases in general health. The strength or slope of this positive relation lessened over time. Conclusions: Social support and the emotion-focused component of social problem solving, problem orientation, independently contribute to caregiver adjustment. Interventions that provide social support and assist caregivers to develop more adaptive abilities toward problem solving may be beneficial. [Copyright &y& Elsevier]

Triclabendazole (TCBZ) is widely used for control of Fasciola hepatica (liver fluke) in animals and humans and resistance to this drug is now widespread. However, the mechanism of resistance to TCBZ is not known. A T687G single nucleotide polymorphism (SNP) in a P-glycoprotein gene was proposed as a molecular marker for TCBZ resistance in F. hepatica (Wilkinson et al., 2012). We analyzed this Pgp gene from TCBZ-susceptible and TCBZ-resistant populations from Australia to determine if the SNP was a marker for TCBZ resistance. From the 21 parasites studied we observed 27 individual haplotypes in the Pgp sequences which comprised seven haplotypic groups (A–G), with haplotypes A and B representing 81% of the total observed. The T687G SNP was not observed in either of the resistant or susceptible populations. We conclude that the T687G SNP in this Pgp gene is not associated with TCBZ resistance in these Australian F. hepatica populations and therefore unlikely to be a universal molecular marker for TCBZ resistance. [ABSTRACT FROM AUTHOR]

Highlights • Sensitivity of nematode larvae to levamisole measured in larval development assay. • Susceptible and resistant Haemonchus contortus and Trichostrongylus colubriformis. • Larval data used to predict efficacy of levamisole against each isolate in vivo. • Predicted and actual in vivo efficacies very similar. • The assay with free-living life stages able to predict levamisole drench efficacy. Abstract The larval development assay has been used for many years to measure the sensitivity of the free-living life stages of trichostrongylid nematodes to anthelmintics. The assay has applications in both drug discovery and the diagnosis of drug resistance. We revisited the usefulness of the larval development assay for diagnosis of resistance to levamisole using field-derived isolates of Haemonchus contortus and Trichostrongylus colubriformis showing varying levels of resistance to this drug in vivo. Each of the resistant isolates showed a plateau in their larval development assay dose-response at the highest drug concentrations tested, representing a highly-resistant fraction, amounting to between 6.9 and 55.1% of the populations. The remaining population fractions for the resistant isolates showed IC 50 values from 1.4- to 17.8-fold higher than their corresponding susceptible isolate of the same species. We used a data set from the DrenchRite® test user manual to derive equations describing the relationship between the IC 50 values for these low / moderate resistance components of each population and in vivo drug efficacy, and then used these equations to estimate the expected in vivo efficacy of levamisole against this population component of each isolate. A combination of this expected efficacy, with the known zero efficacy of the drug in vivo against the highly-resistant population fractions in each isolate, allowed us to calculate a predicted drug efficacy for the whole population for each isolate. The predicted levamisole efficacies for the three resistant H. contortus isolates were 88.8, 84.1 and 43.7%. These compared favourably with the actual efficacy of the drug against these isolates as determined in faecal egg count reduction tests or total worm count studies: 79, 66.3 and 40.6%, respectively. Similarly, for T. colubriformis , predicted efficacies of 82.0 and 1.8% compared favourably with the actual efficacies of 65–92 % and 0%, respectively. This study illustrates the usefulness of the larval development assay as a diagnostic tool for predicting in vivo efficacy of levamisole against H. contortus and T. colubriformis. [ABSTRACT FROM AUTHOR]

The efficacy of commercially available anthelmintics against mature and immature stages (including ovicidal effects) of two Australian field isolates of Ascaridia galli was evaluated in two separate experiments. The anthelmintics tested were levamisole (LEV), piperazine (PIP) and flubendazole (FBZ) plus LEV-PIP. A total of 192 artificially trickle-infected young cockerels (96 birds per isolate) were randomized into sixteen experimental groups of 12 cockerels each (7 treatments and 1 untreated control per isolate). Chickens received label-recommended doses of LEV (28 mg/kg), PIP (100 mg/kg) or LEV-PIP co-administered at their full individual doses as a single oral dose or in group drinking water at recommended concentrations of 0.8 mg/ml or 2.5 mg/ml over eight hours for 1 and 2 days respectively and FLBZ (30 ppm) in the feed over 7 days. Anthelmintic efficacies were assessed by worm count reduction (WCR%) and excreta egg count reduction (EECR%) estimated by two methods. Ten days post treatment, all untreated control birds harboured mixed worm population of 10.1 and 12.3/bird for each isolate respectively which was significantly higher (P < 0.0001) than counts in all treatment groups. Luminal or histotrophic larvae comprised 50–57 % of the total worm count. For LEV, PIP and LEV-PIP, individual oral administration provided a somewhat higher efficacy than group medication in drinking water. EECR% values were inconsistent with WCR% and found to be only an indicator of efficacy against adult worms. All developmental stages of the two A. galli isolates were highly susceptible to FLBZ (100 %) followed by LEV-PIP (92.4–100 %) and LEV (87.7–100 %). PIP exhibited good efficacy against adult worms (92–97 %) but reduced efficacy against luminal (79–84 %) and histotrophic (61–72 %) larvae. Embryonation capacity of eggs recovered from worms expelled after treatment with LEV (47–54 %), PIP (44–54 %) or LEV-PIP (45–48 %) did not differ from those from untreated birds (50–51 %) whereas eggs from FLBZ treated worms had a significantly lower (P < 0.05) capacity to embryonate (≤ 2 %). Put together, our results demonstrate no evidence of resistance of the test A. galli isolates to the tested anthelmintics but a significant advantage of FLBZ, followed by LEV-PIP and LEV over PIP in the control of A. galli, specifically with regard to immature stages. A. galli worms expelled after treatment with LEV, PIP or their combination, but not FLBZ contain viable eggs. This has epidemiological implications and may also provide an option for isolating eggs from mature worms for A. galli propagation experiments without having to sacrifice birds. [ABSTRACT FROM AUTHOR]

• McMaster (MM) is faster than Mini-FLOTAC (MF). • MF is more sensitive than MM at ≤ 50 EPG levels. • MM was more accurate for > 50 EPG levels. • Both MM and MF methods underestimated true egg count in the hands of 4 observers. • Pooled or individual fresh floor excreta samples may predict the true population or flock infection levels. Excreta egg counting techniques are used for indirectly estimating the magnitude of gastrointestinal nematode infection in live animals. The aim of this study was to optimise laboratory and field sampling methods for routine monitoring of nematode infections in chickens by evaluating the sensitivity, accuracy, and precision of the Modified McMaster (MM) and Mini-FLOTAC (MF) methods using laying chicken excreta samples spiked with estimated true numbers of eggs (Experiment 1 = 5−1500 EPG (eggs/g); Experiment 2 = 5–500 EPG) without and with operator effects, respectively or using individual fresh excreta (n = 230) and fresh floor excreta (n = 42) from naturally infected free-range layer farms. The Coefficient of Variation (CV) was assessed within and between operators and the time spent on sample preparation and counting was also evaluated. MF was more sensitive than MM at ≤ 50 EPG level but not above this while MM had a significantly higher egg recovery rate than MF for ≥ 50 EPG levels (MM = 89.7 %, MF = 68.2 %; P < 0.0001). Operator factors did not have a significant effect (P = 0.358−0.998) on egg counts across methods and EPG levels. The CV between replicates of the MM and MF methods for ≥ 50 EPG was 43.4 and 36.5 %, respectively. The inter-observer CV of the MM and MF methods for ≥ 50 EPG levels was 63.8 and 44.3 % respectively. When the naturally infected free-range layers which were individual caged for excreta sampling, the proportion of samples positive for MM and MF were 91.7 and 96.5 %, respectively (P = 0.023). MM resulted in significantly (P = 0.029) higher excreta egg counts (604) than MF (460) with the difference between methods greatest at higher EPG levels. Fresh floor excreta (pooled or individual) and individual caged chicken excreta did not have significant effect on egg counts (P = 0.274). The total time taken for sample preparation and egg counting was significantly lower using the MM method (4.3–5.7 min) than the MF method (16.9–23.8 min) (P < 0.0001). In conclusion, MM was more accurate than MF, particularly at higher EPG levels, but slightly less precise and sensitive, particularly at low EPG levels, while taking less than 25 % of the laboratory time per sample. Our observations indicate that the MM method is more appropriate for rapid diagnosis of chicken nematodes in the field. Pooled fresh floor excreta samples would be sufficient to indicate infection level in free range farms. [ABSTRACT FROM AUTHOR]

Abstract: Purpose: Examination information gained from a simple tactile analogue scale technique (10 cc syringe) of measuring psychological aspects of coping in a low vision patient population. Methods: In routine low vision rehabilitation evaluations, patients were asked to estimate the impact of their vision loss on emotional factors. A 10 cc syringe was used by the patient with closed (0 cc level) indicating no problem and totally open (10 cc level) indicating greatest difficulty. Results: The sample included 25 male and 29 female low vision patients. Mean scores (x /10) for emotional distress variables were frustration 7.4, anxiety 5.5, depression 4.8, fear 4.1, and anger 4.1. Mean scores (x /10) for cognitive appraisal variables were: interference 7.8 and intolerance 4.4. Younger age was associated with greater anger (r =−0.45, p <0.01). No other significant correlations between age or gender and emotional reactions were found. The two cognitive appraisals were better predictors of emotional distress than visual acuity or demographic information. Discussion: This technique demonstrated patients to have a noteworthy amount of distress which is important clinical information in low vision rehabilitation programs. Visual acuity and demographic factors did not predict the distress. This 10 cc syringe technique is inexpensive and easy to administer. It opens a helpful dialogue that may not occur otherwise. Support: Helen Keller Foundation for Research and Education [Copyright &y& Elsevier]

• High prevalence of Fasciola hepatica identified in dairy herds in Victoria, South-eastern Australia. • Highest mean true prevalence of 80 % observed in the Macalister Irrigation District. • Triclabendazole resistance was confirmed in 3 herds. • 46 % of all dairy herds are likely to experience fluke-related production losses. • Total economic losses were estimated to be in the range AUD 38–193 million per annum. Fasciola hepatica (liver fluke) is a widespread parasite infection of livestock in Victoria, South-eastern Australia, where high rainfall and a mild climate is suitable for the main intermediate host Austropeplea tomentosa. The aims of this study were to quantify the prevalence and intensity of F. hepatica in dairy cattle in the irrigated dairy regions of Victoria and determine if triclabendazole resistance was present in infected herds. Cattle in 83 herds from the following six irrigation regions were tested for F. hepatica : Macalister Irrigation District (MID), Upper Murray (UM), Murray Valley (MV), Central Goulburn (CG), Torrumbarry (TIA) and Loddon Valley (LV). Twenty cattle from each herd were tested using the F. hepatica faecal egg count (FEC) as well as the coproantigen ELISA (cELISA). The mean individual animal true prevalence of F. hepatica across all regions was 39 % (95 % credible interval [CrI] 27%–51%) by FEC and 39 % (95 % CrI 27%–50%) by cELISA with the highest true prevalence (75–80 %) found in the MID. Our results show that 46 % of the herds that took part in this study were likely to experience fluke-associated production losses, based on observations that herd productivity is impaired when the true within-herd prevalence is > 25 %. Using the FEC and cELISA reduction tests, triclabendazole resistance was assessed on 3 herds in total (2 from the 83 in the study; and 1 separate herd that did not take part in the prevalence study) and resistance was confirmed in all 3 herds. This study has confirmed that F. hepatica is endemic in several dairy regions in Victoria: triclabendazole resistance may be contributing to the high prevalence in some herds. From our analysis, we estimate that the state-wide economic loss associated with fasciolosis is in the order of AUD 129 million (range AUD 38–193 million) per year or about AUD 50,000 (range AUD 15,000–75,000) per herd per year. [ABSTRACT FROM AUTHOR]

Abstract Resilience following traumatic events has been studied using numerous methodologies. One approach involves quantifying lower-than-expected levels of a negative outcome following trauma exposure. Resilience research has examined personality and coping-related factors. One malleable factor is psychological flexibility, or the context-dependent ability/willingness to contact the present moment, including emotional distress, in order to engage in valued actions. Among 254 war Veterans who participated in a longitudinal study, we operationalized resilience as lower-than-expected PTSD symptoms and PTSD-related functional impairment one-year following an initial post-deployment assessment based on lifetime exposure to childhood trauma, combat trauma, and sexual trauma during military service. We evaluated the contribution of personality factors, self-reported trait resilience, and psychological flexibility, measured using the Acceptance and Action Questionnaire-II, to PTSD-related resilience after accounting for lifetime and current PTSD symptom severity and depression symptom severity. In hierarchical regression analyses, neither specific personality factors nor self-reported resilience predicted PTSD-related resilience at follow-up after accounting for PTSD and depression symptoms. In the final step, psychological flexibility predicted unique variance and was the only significant predictor of PTSD-related resilience aside from baseline PTSD symptom severity. Findings indicate that psychological flexibility is a predictor of resilience that is distinct from psychiatric symptoms, personality, and self-reported resilience. Trauma survivors may benefit from interventions that bolster psychological flexibility. Highlights • Psychological flexibility, as indexed by the AAQ-II, was a significant predictor of PTSD-related resilience over time. • Psychological flexibility remained a significant predictor after covarying PTSD and depression symptom severity. • Neuroticism and self-reported trait resilience were not significant predictors in the full model. • Targeting psychological flexibility following trauma may bolster resilience and promote recovery. [ABSTRACT FROM AUTHOR]

Liver fluke ( Fasciola hepatica ) infection is an increasing threat to livestock production resulting in serious economic losses to the beef, dairy and sheep industries in Australia and globally. Triclabendazole (TCBZ) is the main drug used to control liver fluke infections in Australia and the widespread emergence of TCBZ resistance in cattle and sheep threatens liver fluke control. Alternative control measures to lower exposure of livestock to fluke infection would be useful to help preserve the usefulness of current chemical flukicides. Environmental DNA (eDNA) sampling methodology and associated molecular techniques are suited to rapidly assess the presence of pathogens on farms. In the present study, we developed a water sampling method in combination with a multiplex quantitative PCR assay to detect and quantify DNA of F. hepatica and Austropeplea tomentosa ( A. tomentosa ), a crucial intermediate snail host for liver fluke transmission in South-east Australia. The multiplex qPCR assay allows for the independent detection of F. hepatica and A. tomentosa DNA using specific primers and a probe targeting the ITS-2 region of the liver fluke or snail. The method allows the highly specific and sensitive (minimal DNA detection levels to 14–50 fg) detection of F. hepatica or A. tomentosa . The method allows the detection of both liver fluke and snail eDNA in water samples. The effective quantification of liver fluke and snail eDNA in water samples using this assay could potentially allow researchers to both identify and monitor F. hepatica transmission zones on farming properties in South-east Australia which will better inform control strategies, with potential application of the assay worldwide. [ABSTRACT FROM AUTHOR]

Sieve elements (SEs) degrade selected organelles and cytoplasmic structures when they differentiate. According to classical investigations, only smooth ER, mitochondria, sieve element plastids, and, in most cases, P-proteins remain in mature SEs. More recent proteomics and immuno-histochemical studies, however, suggested that additional components including a protein-synthesizing machinery and a fully developed actin cytoskeleton operate in mature SEs. These interpretations are at odds with conventional imaging studies. Here we discuss potential causes for these discrepancies, concluding that differentiating SEs may play a role by ‘contaminating’ phloem exudates. [ABSTRACT FROM AUTHOR]

• Day-old chickens are suitable for use in an infection model to propagate A. galli. • The most efficient dose for multiplying stocks of A. galli eggs was 300 eggs/chick. • Immunosuppression with dexamethasone increased worm load and worm egg counts. • galli worms attained high egg production capacity at 8 weeks post-infection. • galli infection caused a dose dependent reduction in body weight gain. With the continued growth of free-range egg production, the importance of the chicken roundworm Ascaridia galli is increasing. Investigations into this parasite would be facilitated by the availability of characterised strains and clear guidelines on optimal methods of multiplication and maintenance. Currently, there is lack of well-defined in vivo models for maintaining A. galli and the potential of using host immunosuppression to boost parasite development and worm egg output has not been investigated. To determine the most efficient way of propagating A. galli in young chickens an experiment with a 2 × 3 × 4 × 2 factorial design involving age of chicken at infection (day-old or 14 days old), immunosuppression (dexamethasone (DEX), cyclophosphamide (CY) or sham), infective egg dose (0, 100, 300 or 900 embryonated eggs/bird) and time of worm recovery after infection (8 or 10 weeks post-infection) was conducted. The experiment used a total of 384 layer cockerel chicks. Infection was delivered orally in 3 split doses over one week and immunosuppressants were administered by intramuscular injection concurrently with the infections. Body weight, excreta egg counts, intestinal worm count and worm establishment rate were assessed. The only sign of ascaridiosis noted was mild diarrhoea at the time of slaughter in some birds with a significant- positive association with worm count. Infection caused a significant dose dependent reduction in body weight in non-immunosuppressed birds but this effect was ameliorated by immunosuppression. Age at infection had no significant effect on the studied variables although both worm and egg counts were numerically higher in the day-old infected groups. Egg dose significantly influenced the prevalence of infection, worm establishment rate, worm egg production and mean worm count. The 300 and 900 egg doses resulted in significantly higher worm count and egg production than the 100 egg dose. A significant negative correlation was observed between egg dose and worm establishment rate indicating an inverse relationship. Immunosuppression with DEX, but not CY resulted in significantly higher mean worm burden than in control chickens with excreta egg counts also considerably higher in DEX treated birds. Our results suggest that trickle infection at day-old with infective doses of 300 eggs coupled with immunosuppression with DEX would provide the most efficient way to propagate A. galli worms in vivo , as using older birds or a higher egg dose did not provide any advantage. [ABSTRACT FROM AUTHOR]

Gastrointestinal helminth parasites are a concern for the poultry industry worldwide as they can affect the health, welfare, and production performance. A systematic review of the prevalence over time in different countries may improve our understanding of gastrointestinal helminthiasis in chickens and subsequently lead to improved poultry health. The aim of this systematic review and meta-analysis was to provide an overview of the published information regarding the epidemiology and the diagnostic approaches of chicken helminth infection. Six databases were searched for studies, and a total of 2,985 articles published between 1942 and 2019 were identified and subsequently screened for eligibility using title or abstract and full text assessment, resulting in 191 publications to be used in the study. Postmortem diagnostics (73.8%) and the flotation technique (28.8%) were commonly used to detect helminth infections with a pooled prevalence of 79.4% ranging from 4 to 100%. More than 30 helminth species in chicken populations were identified including Ascaridia galli (35.9%), Heterakis gallinarum (28.5%), Capillaria spp. (5.90%), and Raillietina spp. (19.0%) being the most prevalent. The reported prevalence of helminth infection decreased over time in developing countries while it increased in the developed world. Chicken kept in backyard and free-range systems had a markedly higher pooled prevalence of helminth infection (82.6 and 84.8%, respectively) than those housed in cage production systems (63.6%). This may indicate the need for more rigorous control and prevention measures in free-range and backyard production systems using regular deworming coupled with access to early and accurate diagnosis allowing for early intervention. [ABSTRACT FROM AUTHOR]

[Display omitted] • Treatment of Fasciola hepatica is problematic due to increasing drug resistance. • Alternative measures to lower exposure of livestock to fluke infection are needed. • We were able to detect F. hepatica and the snail host eDNA from field sampled water by qPCR. • Differential levels of liver fluke and snail eDNA changed over the year. • This method allows assessment of the liver fluke transmission zones on farms Livestock production around the world is impacted by liver fluke (Fasciola spp.) infection resulting in serious economic losses to the beef, dairy and sheep industries with significant losses of about $90 million per annum in Australia. Triclabendazole (TCBZ) is the most effective anthelmintic treatment available to control liver fluke infections; however, the widespread emergence of TCBZ resistance in livestock threatens liver fluke control. Alternative control measures to lower exposure of livestock to liver fluke infection would help to preserve the usefulness of current anthelmintic treatments. Environmental DNA (eDNA) based identification of liver fluke and the intermediate snail host in the water bodies is a robust method to assess the risk of liver fluke infection on farms. In this study, we used a multiplex quantitative PCR assay of water samples to detect and quantify eDNA of Fasciola hepatica (F. hepatica) and Austropeplea tomentosa (A. tomentosa), a crucial intermediate snail host for liver fluke transmission in South-east Australia. Water samples were collected from an irrigation channel for a period of 7 months in 2016 (February, March, May, September, October, November and December) at a dairy farm located at Maffra, Victoria, South-east Australia. Using an effective eDNA extraction method, the multiplex qPCR assay allows for the independent but simultaneous detection of eDNA released from liver fluke life stages and snails using specific primers and a probe targeting the ITS-2 region of the liver fluke and snail, respectively, with minimal inhibition from contaminants in field collected water samples. The sensitivity of this assay to detect eDNA of liver fluke and snails was observed to be 14 fg and 50 fg, respectively, in the presence of field collected water samples. Differential levels of liver fluke and snail specific eDNA in water were observed at the time points analysed in this study. The successful detection of eDNA specific to liver fluke and snails from the field collected water samples provides a precedent for the use of this method as a monitoring tool to determine the prevalence of liver fluke and liver fluke-transmitting snails in irrigation regions. Further, this method has the enormous potential to allow an assessment of the liver fluke transmission zones on farms and to inform the application of effective control strategies. [ABSTRACT FROM AUTHOR]