Anthelmintic Resistance in Equine Nematodes – A Review on the Current Situation, with Emphasis in Europe

Since the introduction of the last equine broad-spectrum anthelmintic group in the 1980’s, the investment in new drugs to control horse’s parasites did not result in new advancements. These drugs allowed a very effective and extensive control of equine nematodes through successful interval dosing programs, firstly introduced in the 1960’s. However, the widespread and indiscriminate use of anthelmintics in these intensive treatments have led to increasing resistance in the major equine nematodes. Reports of reduced effectiveness are virtually worldwide and repercussions in livestock production farms have already been seen.Based on recent questionnaires about horse farm practices, preventive measures and international recommendations, it is clear that most of them are still not being widely implemented. It is also clear that these recommendations are outdated and new approaches must be considered to correctly tackle this rapidly evolving issue in horse management, as more accurate diagnostic methods are currently available, such as Mini-FLOTAC. This article intends to do a general review of the history and current situation of anthelmintic resistance in horses, with emphasis in Europe, as well as, how to diagnose and delay or even prevent its further development, mentioning new methods of diagnostic and directions in which to develop research

Parasitas gastrointestinais em produção de frango ao ar livre

A investigação em sanidade animal realizada a nível nacional em sistemas extensivos de produção de frango é essencial, atendendo à frequente longa exposição dos animais ao ambiente exterior e aos parasitas que o contaminam. Estudos parasitológicos são extremamente relevantes de forma a conhecer quais as espécies parasitárias mais prevalentes e ajudar os produtores a definirem melhores medidas profiláticas. Esta pesquisa procurou identificar os parasitas gastrointestinais associados a este tipo de produção aviária e ocorreu numa exploração agropecuária localizada na extremidade noroeste do distrito de Lisboa, onde foram avaliados Frangos do Campo através de amostragem fecal aos 75 e 85 dias de idade. O parasitismo gastrointestinal foi analisado através de métodos coprológicos qualitativos, quantitativos e coproculturas para obtenção de oocistos esporulados e larvas L3 de nematodes estrongilídeos. Na 1ª amostragem, a prevalência de Eimeria spp. totalizou 40,0%, sendo Eimeria mitis (13,3%) e E. maxima (11,7%) as mais prevalentes, tendo-se identificado também ovos de Capillaria sp., (1,7 % de prevalência). Nas coproculturas de oocistos, esporularam as seguintes espécies: E. necatrix, E. mitis, E. praecox, E. maxima, E. acervulina e E. tenella. Na 2ª amostragem, as coccídeas continuaram a ser o grupo mais prevalente, 90,0% de amostras positivas com oito espécies identificadas, sendo de novo E. mitis a espécie mais frequente (41,7%), seguida por E. acervulina (26,7%) e E. tenella (25%). Foram também observados ovos de Heterakis sp. (3,33%) e novamente de Capillaria sp. (10,0%) A carga parasitária fecal de oocistos na 1ª e 2ª amostragens foi de 370,8 ± 2055,3 OoPG e 599,2 ± 1289,2 OoPG, respetivamente, verificando-se um aumento superior a 60% do valor médio deste parâmetro parasitológico da 1ª para a 2ª colheita. O crescimento da erva, a idade e densidade animal, bem como o tempo de exposição a parasitas com períodos pré-patentes curtos, constituíram fatores chave para o aumento da prevalência de oocistos de Eimeria spp. e ovos de helmintes entre as duas amostragens, em particular de espécies com reconhecida patogenicidade. Isto permite-nos concluir que no final da fase de engorda, as cargas parasitárias são as mais elevadas detetadas neste sistema de produção de Frango do Campo, podendo desencadear patologia associada e interferir com a sua performance produtiva.info:eu-repo/semantics/publishedVersio

Biocontrol of Avian Gastrointestinal Parasites Using Predatory Fungi: Current Status, Challenges, and Opportunities

This review describes the current research status regarding the implementation of predatory fungi in the biological control approach of bird gastrointestinal (GI) parasitosis. The main GI parasites of Galliformes (e.g., broilers, layers, peacocks, pheasants) and Ratites (e.g., ostriches, emus, rheas) are addressed, as well as their impact on farms, zoos, and private collections. The main characteristics regarding biocontrol with predatory fungi are briefly described, such as their mode of action and efficacy against GI parasites of different animal hosts. The state of the art regarding the use of predatory fungi in birds is reviewed here by describing all associated articles already published in the main databases, techniques, and their main findings. Ovicidal fungi such as Pochonia chlamydosporia, Metarhizium spp. and Acremonium spp., and larvicidal fungi, namely Duddingtonia flagrans, Arthrobotrys spp. and Monacrosporium thaumasium, have shown promising predacious activity against ascarid eggs and nematode larvae from chickens and ostriches, both in vitro and in vivo, also revealing tolerance to the GI passage in chickens and maintenance of predacious capacity. Further studies are needed to understand the fungi–parasite–host gut microbiota interactions and target other avian GI parasitic species, such as nematodes, coccidia, cestodes, and trematodes.info:eu-repo/semantics/publishedVersio

Gastrointestinal parasitism in Miranda donkeys : epidemiology and selective control of strongyles infection in the Northeast of Portugal

Research Areas: Agriculture ; Veterinary Sciences ; ZoologyIn Portugal, equine parasitism in pasture animals is characterized by high parasitic burden and high helminthic biodiversity; both factors are potentially pathogenic for their hosts. The decrease in the number of donkeys over the last years in Portugal, their importance in rural lowland and mountain ecosystems and pastures and the scarce information regarding their parasitism led to this research, which aimed to evaluate the parasitological status of a Miranda donkey breed population, a native breed mainly located in the northeast of Portugal. This study provides better knowledge of their gastrointestinal parasitism, particularly strongyles, and the assessment of a targeted selective treatment (TST) as an alternative control approach of their parasitism. A longitudinal observational study was developed during a period of five years in a population of 62 Miranda donkeys. At first, strategic deworming of these animals was performed every semester, but this was progressively replaced by a TST approach according to the levels of Eggs per Gram (EPG). This new deworming strategy was conducted in association with a regular parasitological monitoring of the animals every three months, being dewormed with ivermectin when egg shedding was higher than 500 EPG. Over the study period, a decrease of the annual prevalence rate of infection by gastrointestinal strongyles was observed, from 35.5% to 19.4%, as well as a negative binomial distribution of parasitic strongyles in donkeys submitted to selective anthelminthic control. The prevalence rate of infection was higher in females (39.5%), in individuals under four years (46.7%) and in those presenting a lower body condition (40.8%). The egg output was higher in animals younger than four years (589.3 EPG) than in those older than 10 years (533.6 EPG) (p < 0.05). However, no differences were observed according to sex during the study period. Results from this study allowed to note the influence of swampy pastures and of the weather changes in the epidemiology of strongylosis in Miranda donkeys. Moreover, it was possible to establish the annual epidemiological curve of strongyle egg shedding, with June being the month with the highest EPG, December having the lowest EPG and March and September showing intermediate numbers. Overall, a lower biodiversity of gastrointestinal parasites was observed. Cyathostomum sensu lato was the most prevalent genus and Strongylus vulgaris was the most observed large strongyle of the Strongylidae family. Trichostrongylus axei and Parascaris sp. were other nematodes with a minor frequency. The higher prevalence of strongyles at the beginning of the study showed a progressive decrease throughout the research period, and also for parasite biodiversity. Therefore, a targeted selective treatment seems to be a rational anthelminthic control approach in Miranda donkey strongyle infection and in other gastrointestinal parasites, since it reduces the antiparasitic treatments, the parasite’ prevalence and the EPG level. However, a loss of parasite biodiversity was noted at the end of the study period, as Cyathostominae were the only isolated strongyles. This can be a challenging situation in the long run, taking the ability of these nematodes to adapt easily to any deworming program, meaning that fecal EPG monitoring should be kept as a rule to a rational parasite control program.info:eu-repo/semantics/publishedVersio

Preliminary findings on the gastrointestinal parasites of the brown bear (Ursus arctos) in the Cantabrian mountains, Spain

Research Areas: Parasitology ; Veterinary SciencesABSTRACT - No study is currently available on the parasitofauna of the population of brown bears (Ursus arctos) inhabiting the Cantabrian Mountains in Spain. The aim of the present study was to obtain novel information on diversity and prevalence of gastrointestinal parasites in these individuals. During August 2016 and from May to July 2017, 14 fecal samples were collected from the western Cantabrian bear subpopulation, in the Somiedo Natural Park, in the Spanish province of Asturias. The prevalence of parasites detected was 71% and two genera were identified: Dicrocoelium sp. and Trichuris sp. Since the impact that pathogens such as endoparasites can have on the health of bears, together with other stressors, is still poorly understood, research efforts that include disease surveillance are critical to the successful protection of this emblematic species. Our preliminary findings require further investigations, with a wider sampling effort, and bring awareness for the need of carrying further studies on this area as a part of a proactive species management plan.info:eu-repo/semantics/publishedVersio

Genetic variability, cryptic species and phylogenetic relationship of six cyathostomin species based on mitochondrial and nuclear sequences

Cyathostomins are important intestinal nematode parasites of equines and include 50 accepted species. Their taxonomy has been frequently revised and the presence of cryptic species suggested. Furthermore, usually molecular- and morphology-based phylogenetic analyses give divergent results. In this study, the nucleotide sequences of the nuclear second internal transcribed spacer (ITS-2) and the mitochondrial partial cytochrome c oxidase subunit I (COI) were determined for adults of six cyathostomin species (Coronocyclus coronatus, Coronocyclus labiatus, Cylicocyclus nassatus, Cylicostephanus calicatus, Cylicostephanus longibursatus, Cylicostephanus minutus) collected from different equine species within two geographic regions. Maximum likelihood trees were calculated for ITS-2, COI, and concatenated data. No obvious differentiation was observed between geographic regions or equine host species. As previously reported, Coronocyclus coronatus and Cylicostephanus calicatus revealed a close relationship. Cryptic species were detected in Cylicostephanus minutus and Cylicostephanus calicatus. Cylicocyclus nassatus and Coronocyclus labiatus showed diverse mitochondrial and nuclear haplotypes occurring in different combinations, while Cylicostephanus longibursatus was comparatively homogenous. In conclusion, a combined analysis of nuclear and mitochondrial haplotypes improved resolution of the phylogeny and should be applied to the remaining cyathostomin species and across additional equine host species and geographic regions

Feline thelaziosis caused by Thelazia callipaeda in Portugal

Thelazia callipaeda (Spirurida, Thelaziidae) is a nematode that lives in the conjunctival sac of domestic and wild carnivores, rabbits and humans causing mild to severe symptoms (e.g., conjunctivitis, lacrimation, epiphora, blepharospasm, keratitis and even corneal ulceration) in infected animals. This report describes an autochthonous case of thelaziosis in a cat from the central region of Portugal, representing the most occidental record of thelaziosis in Europe. Adult nematodes recovered from alive animal were morphological identified as T. callipaeda. A portion of the mitochondrial cytochrome c oxidase subunit 1 gene (cox 1) from nematode specimens was amplified by PCR. Cox1 sequences of all specimens were identical to T. callipaeda haplotype 1. Additionally to these findings, a recent description of thelaziosis in the northern region of Portugal suggests that T. callipaeda has successfully established in Portugal

Diagnosis of coccidiosis by Eimeria spp. in free-range chickens using Mini-FLOTAC and McMaster techniques - preliminary results

Mini-FLOTAC is emerging as a more sensitive and accurate tool to identify gastrointestinal parasites in faecal samples from domestic animals, in comparison with the McMaster method. However, research regarding its specific application in poultry samples, particularly from free-range chickens, is scarce. The current research aimed to test the use of Mini-FLOTAC for the identification of Eimeria spp. in free-range chickens and compare its results with McMaster. For this study, 40 faecal samples were collected from free-range chickens in a poultry farm located in North-Western Lisbon (Portugal). Each sample was processed with McMaster and Mini-FLOTAC techniques for the detection and count of coccidian Eimeria spp. oocysts. The resulting OPG (oocysts per gram of faeces) data obtained by the two techniques were compared using the Wilcoxon Test and correlated with the Spearman Test, and Mini-FLOTAC’s relative sensitivity was assessed, using a significance level of p<0.05. The average OPG was higher with Mini-FLOTAC and doubled the one obtained using the McMaster method (2669.3 OPG and 1220 OPG, respectively), although these results were not significant. Mini-FLOTAC’s relative sensitivity obtained in this study reached 86% (70.5-95.3%, 95%CI), although this result was not statistically significant. However, correlation of OPG counts between Mini-FLOTAC and McMaster, was significant. These preliminary results suggest the potential interest in the use of Mini-FLOTAC for the diagnosis of coccidiosis by Eimeria spp. in poultry, based on its assessment in a free-range poultry production system.info:eu-repo/semantics/publishedVersio

Gastrointestinal parasites of free-range chickens : a worldwide issue

Gastrointestinal parasites with direct and/or indirect life cycles, namely Eimeria spp., Ascaridia galli, Heterakis gallinarum and Capillaria spp., are responsible for the most frequent and heavy economic losses in aviculture. The current review aimed to collect information about gastrointestinal parasites affecting poultry, as well as, research studies regarding parasitic diseases in free-range chicken production. From the references used in this review, 20% highlight research studies correlating prevalence of gastrointestinal parasites in free-range chickens and factors such as the production system, age and animal density, hygienic conditions and weather. Coccidiosis is responsible for the major economic losses in poultry farms. Diseases have different clinical signs and result in variable impacts on animals. Control programs include mainly vaccination, anti-coccidia and anthelminthic drugs, as well as, house cleaning and disinfection. This review concluded that coccidia and helminths are a global threat to free-range poultry production. More research in this area is necessary in order to understand the major factors influencing the prevalence of parasitic diseases in this type of poultry production. Also the search for new control strategies must be a priority, mainly using natural antiparasitic compounds and biological control approaches.info:eu-repo/semantics/publishedVersio

Blended learning no ensino superior: um programa de formação em e-Learning para professores da Universidade Técnica de Lisboa

A convergência da tradicional sala de aula presencial com a educação online constitui uma das mais importantes tendências do ensino superior actual, nomeadamente sob a forma de blended learning, colocando novos desafios à função docente no Ensino Superior e criando novas necessidades de formação em contexto universitário. Nesse sentido, no âmbito da cooperação entre a Universidade Aberta e a Universidade Técnica de Lisboa, teve lugar o 1º Curso de Formação Integrada em e Learning, desenvolvido na Universidade Aberta por uma equipa do LEaD (Laboratório de Ensino a Distância), com vista à aquisição de competências no domínio do elearning por parte de docentes da UTL.info:eu-repo/semantics/publishedVersio