scholarly journals Entomopathogenic Nematodes: Biological Model of Studies with Anthelmintics

2021 ◽  
Author(s):  
Oscar Barrón-Bravo ◽  
Ismael Montiel-Maya ◽  
Ana Cruz-Avalos ◽  
Fidel Avila-Ramos ◽  
Jaime Molina Ochoa ◽  
...  

Anthelmintics used in animals to combat parasitic infections are mainly excreted in manure and cause negative effects on the environment and decomposers. Nematodes are associated with the rhizosphere; some are gastrointestinal parasites of animals, and others regulate insects and other arthropods (entomopathogenic nematodes) and are considered beneficial. The habitat and the similarities that exist among them give the opportunity to use nematodes as a biological model. The availability of target organisms is not always feasible; therefore, experimental studies with models similar to those of the target organisms are a possibility. In veterinary clinics, the study of drug susceptibility is a fundamental tool to monitor the development of resistance. To conserve the biodiversity of the environment, it is necessary to make adequate use of anthelmintics, avoid resistance to these pesticides and prevent the used products from damaging populations of beneficial organisms.

2020 ◽  
Vol 79 (Suppl 1) ◽  
pp. 1633.2-1634
Author(s):  
F. Cosan ◽  
O. M. Gedar

Background:Reactive arthritis (ReA) is defined by 1999 ACR criteria as arthritis preceding a bacterial genitourinary (GUS) or gastrointestinal (GIS) infection in 3 days-6 weeks and evidence of triggering infection. Recently, ReA is classified as SpA and patients who do not fulfill SpA criteria are classified as undifferentiated spondyloarthritis (USpA) according to ASAS/EULAR SpA classification criteria.Objectives:In several case reports which are associated with other infective agents are reported and the definition is extended for some clinicians so that SpA which is occurred after any infection is called as ReA. On the other hand, some researchers still accept the classical definition of ReA. The problem with the heterogeneity of opinions and unstandardized definition of ReA hinders studies about pathogenesis and standardization of treatments. In this study, we aimed to determine the spectrum of the use of the definition of reactive arthritis in publications in PubMed between 2009-2019.Methods:The ReA keyword is searched in PubMed for the years between 2009-2019. 248 different publications have been identified and included in this research. 89 articles, 47 reviews, 108 case reports, 2 guidelines, and 2 editorials reviewed for the definition of ReA.Results:Only 42.7% (106 patients) of these publications meet the classical definition which suggests ReA after only GIS and GUS infections. In 4 (1.6%) of the publications ReA was defined after GIS, GUS and oropharyngeal infections; in 3 (1,2%) of the publications after any bacterial infection; in 9 (3.6%) of the publications after any infection. In 8 (3.2%) of the publications, ReA and USPA was used correspondingly. In 39 (15,7%) of the publications the term agent related, ReA was used without making a general definition for ReA. 79 publications (31,9%) have not defined ReA.According to causative agent and ReA relationship, in 64 (24,6%) general infective agents, in 75 (30,2%) classical agents, in 22 (8,9%) other bacterial agents, in 23 (9,3%) streptococcus, in 10(4%) intravesical BCG, in 6 (2.4%) HIV, in 6 (2.4%) tuberculosis, in 12 (4,8%) clostrudium difficle, in 2 (0.8%) parasites were reported. In 31 (12,5%) of the publications the causative agent for the ReA was unknown, the diagnosis was made clinically.Conclusion:In this study, it is aimed to draw attention terminology intricacy and the need for the standardization of the definition of ReA and USpA. It is clear that to standardize the definition of Rea and USpA is necessary. Between 2009-2019 there are reported cases diagnosed as ReA associated with bacterial infections (especially with Clostridium difficile, streptococcus and tuberculosis infections), and viral infections (by a majority with HIV), and parasitic infections. It is not clear if we need to define them classically or define them as USPA. Another important consideration is the necessity of extended laboratory investigations to find out the real causative agent even if the patient is clinically diagnosed with ReA. The requirement of the differentiation between ReA and USpA must be revealed for therapeutic researches.References:[1]A proposal for the classification of patients for clinical and experimental studies on reactive arthritis. Pacheco-Tena C, Burgos-Vargas R, Vázquez-Mellado J, Cazarín J, Pérez-Díaz JA. J Rheumatol. 1999 Jun;26(6):1338-46.[2]The Assessment of SpondyloArthritis International Society classification criteria for peripheral spondyloarthritis and for spondyloarthritis in general. Rudwaleit M, van der Heijde D, Landewé R, Akkoc N, Brandt J, Chou CT, Dougados M, Huang F, Gu J, Kirazli Y, et al. Ann Rheum Dis. 2011;70:25–31.Disclosure of Interests:None declared


2019 ◽  
Vol 15 (1) ◽  
Author(s):  
Si-Yuan Qin ◽  
Ming-Yang Yin ◽  
Guang-Yao Song ◽  
Qi-Dong Tan ◽  
Jin-Lei Wang ◽  
...  

Abstract Background Little information about the prevalence of gastrointestinal parasites in yaks (Bos grunniens) in northwest China is available. Therefore, the objective of the study was to quantify faecal egg counts of gastrointestinal parasites (helminths and coccidia) in free-range yaks from Gannan Tibetan Autonomous Prefecture, Gansu Province, Northwest China. Results Parasites were detected in 290 of 733 (39.56%) faecal samples. The results showed that Strongylidae, Trichuris spp. and Eimeria spp. were detected all year round, Strongyloides papillosus was detected in autumn and summer, and Nematodirus spp. was detected in both autumn and spring. In contrast, Fasciola spp. was only detected in spring. The prevalence rates of parasitic infections in different seasons were significantly different. Conclusions To our knowledge, this is the first investigation of gastrointestinal parasites in yaks (Bos grunniens) in Gansu, China. The results demonstrated a high prevalence of gastrointestinal parasitic infections, specifically GN infections, in yaks in GTAP and these infections can cause economic losses to the local cattle industry.


Parasitology ◽  
1989 ◽  
Vol 99 (S1) ◽  
pp. S21-S35 ◽  
Author(s):  
D. Wakelin

SUMMARYParasitic infections in man and domestic animals exhibit two striking characteristics (a) their prevalence is high, but infections are unequally distributed among individuals within populations and (b) immunity is often slow to develop and appears, at best, only partially effective. Recent immunological and epidemiological studies suggest that effective immunity can develop, but that high prevalence within populations reflects the operation, not only of socio-economic and climatic factors, or husbandry practices, but also of powerful environmentally induced constraints upon the development of resistance. Immunogenetic studies suggest the operation of additional constraints which reflect individual genetic characteristics, and which influence the ability to develop and express effective immunity. A full understanding of all constraints is necessary before levels of population and individual resistance to infection can be increased; the need for such understanding has become more pressing with the prospect that anti-parasite vaccines may become available. Two aspects of environmentally induced constraints are considered, those arising from nutritional inadequacies and those resulting from exposure to infection in early life. Both are discussed primarily in terms of helminth parasites. Genetically determined constraints are discussed with reference to MHC-restricted recognition of malarial peptide vaccines and in terms of Class II molecule-directed control of T-cell function inLeishmaniainfections. Genetic influences are also considered from the standpoint of inflammatory cell function, in immunity against intestinal nematodes and in vaccine-induced immunity againstSchistosoma. Finally, parasite-induced constraints, particularly those which down-regulate protective responses are discussed briefly.


2021 ◽  
Vol 1 (1) ◽  
pp. 72-78

The article presents the results of laboratory studies to assess the toxicological parameters of montmorillonite clay from the Pogadaevskoye deposit in the West Kazakhstan region in order to use them as an aluminosilicate sorbent in the composition of feeds that reduce the negative effects of mycotoxins on the body of animals and birds. The relevance of research is associated with the cultivation of healthy and highly productive animals and poultry in order to ensure the food security of the Republic of Kazakhstan.The studies carried out to assess the toxicological parameters of montmorillonite clay in order to use them as an aluminosilicate sorbent in experimental animals (rabbits and white rats) allowed the following results to be obtained: Visual study of the intensity of erythema when exposed to the test substance on the skin of rabbits showed their absence (0 points). The study of the intensity of edema (an increase in the thickness of the skin clutch of rabbits) when exposed to the test substance on the skin of rabbits showed no reaction (0 points). Studies evaluating the irritating effect of the test substances on the mucous membranes of the eyes of rabbits by symptoms of damage showed the absence of hyperemia (0 points). Weak eyelid edema (1 point), the minimum amount of discharge in the corner of the eye (1 point). The results of studies on the classification assessment of the test substance for the severity of the irritant effect on the eyes of rabbits showed that the average total score of the severity of the irritative effect corresponds to 1 point. A comprehensive analysis of the results obtained on the basis of scientific and experimental studies to assess the toxicological indicators of montmorillonite clay from the Pogadaevskoye deposit in relation to irritating effects on the skin and mucous membranes of experimental animals (rabbits) showed their harmlessness.


2017 ◽  
Vol 26 (4) ◽  
pp. 427-432 ◽  
Author(s):  
Plínio Aguiar de Oliveira ◽  
Beatriz Riet-Correa ◽  
Pablo Estima-Silva ◽  
Ana Carolina Barreto Coelho ◽  
Bianca Lemos dos Santos ◽  
...  

Abstract Gastrointestinal parasites represent an important cause of reduced productivity of sheep worldwide. As anthelmintic are still the main control tool for these parasites, this work evaluated the efficacy of commercially available active principles in 22 sheep flocks in the southern region of Rio Grande do Sul, Brazil. In each farm 10 sheep were randomly distributed in seven groups with the following treatments: abamectin; albendazole; closantel; levamisole; monepantel; trichlorphon and no anthelmintic (control). All flocks showed resistance to at least three anthelmintics and in 20 farms only two products demonstrated efficacy for parasitic control. In two farms, there was no susceptibility to the six active principles tested. The results of this study provide evidence that the common commercially available anthelmintic are not assuring effective chemical control of gastrointestinal parasitic infections in ovine flocks in the southern region of Rio Grande do Sul. Monepantel, the newest introduced drug in the Brazilian market was not effective in 18% of the flocks tested, confirming that the parasitic resistance can be established quickly after the introduction of new molecules mainly when alternative program of parasite control is not performed.


2020 ◽  
Author(s):  
Brandi Wren ◽  
Ian S. Ray ◽  
Melissa Remis ◽  
Thomas R. Gillespie ◽  
Joseph Camp

AbstractSocial grooming in the animal kingdom is common and serves several functions, from removing ectoparasites to maintaining social bonds between conspecifics. We examined whether time spent grooming with others in a highly social mammal species was associated with infection status for gastrointestinal parasites. Of six parasites detected, one (Trichuris sp.) was associated with social grooming behaviors, but more specifically with direct physical contact with others. Individuals infected with Trichuris sp. spent significantly less time grooming conspecifics than those not infected, and time in direct contact with others was the major predictor of infection status. One model correctly predicted infection status for Trichuris sp. with a reliability of 95.17% overall when the variables used were time spent in direct contact and time spent grooming others. This decrease in time spent grooming and interacting with others is likely a sickness behavior displayed by individuals with less energy or motivation for non-essential behaviors. This study highlights the need for an understanding of a study population’s parasitic infections when attempting to interpret animal behavior.


2021 ◽  
Author(s):  
Aurora L. Ursache ◽  
Adriana Györke ◽  
Viorica Mircean ◽  
Mirabela Oana Dumitrache ◽  
Andrei Răzvan Codea ◽  
...  

Abstract Gastrointestinal parasites are involved in the health and wellbeing of cats and some of them, due to their zoonotic character represent a problem for the public health. This study aimed to assess the prevalence of parasitic infections in cats with digestive symptoms. Faecal samples collected from 137 cats were analysed by the flotation method using sodium chloride saturated solution. The overall prevalence of gastrointestinal (GI) parasites was 56.6%. GI parasites were significantly (p=0.005) more common in cats with digestive symptoms (69.8%) than in clinically healthy ones (23.0%). Toxocara cati (40.2%) was the most frequently identified GI parasite, followed by Cystoisospora spp. (10.2%), Ancylostoma tubaeforme (3.7%), Taenia spp. (2.2), Giardia duodenalis (2.2%), and Toxoplasma gondii-like oocysts (0.7%). T. cati (53.3%, p<0.0001) and Cystoisospora spp. (15.6%, p<0.001) were significantly more frequently diagnosed in cats with digestive symptoms. Lack of deworming in the last three months (OR: 15.9), outdoor access (OR: 13.8), the presence of digestive symptoms (OR: 5.4), and young age (OR: 4.2) were identified as risk factors for T. cati infection by logistic regression analysis. Regardless of the age, symptoms like vomiting, diarrhoea, and inappetence were positively associated with T. cati.


2013 ◽  
Vol 42 (2) ◽  
pp. 139-142
Author(s):  
TC Nath ◽  
MJU Bhuiyan ◽  
MS Alam

To investigate the prevalence of gastrointestinal parasites of calves, 450 feacal samples were collected from Mirsarai Upazilla of Chittagong District of Bangladesh during the period from 2011 to 2012. Fecal samples of calves aged up to 6 months of three different genotypes were examined for gastrointestinal parasites. The results of faecal examination revealed that 54.22% calves were infected with some of the parasites. Toxocara spp (22.66%), Eimeria spp (17.33%), Strongyloides spp (6.44%), gastrointestinal strongyles (3.78%), Moniezia spp (01.78%), Trichuris spp (01.56%) and Fasciola gigantica (0.66%) were found. We found eggs of Toxocara spp eggs, Strongyloides spp eggs and oocysts of Eimeria spp during the age of first month, gastrointestinal strongyles eggs and Moniezia eggs at/during/within the age of 3 months and eggs of Trichuris spp and Fasciola gigantic during the age of five months of age. Prevalence of gastrointestinal parasites in Local, Shahiwal cross and Holstein Frisian cross were 46%, 52% and 62%, respectively. The age and genotype of the calves and the locality of investigations might have influenced the prevalence of the parasitic infections. DOI: http://dx.doi.org/10.3329/bjas.v42i2.18494 Bang. J. Anim. Sci. 2013. 42 (2): 139-142


2017 ◽  
Vol 26 (4) ◽  
pp. 521-524 ◽  
Author(s):  
Victor Fernando Santana Lima ◽  
Rafael Antonio Nascimento Ramos ◽  
Raphael Lepold ◽  
João Carlos Gomes Borges ◽  
Carlos Diógenes Ferreira ◽  
...  

Abstract Gastrointestinal parasites are important pathogens affecting animals, some of them are of medical and veterinary concern. Although the dynamic of parasitic infections is a complex phenomenon that has been studied under experimental conditions, it shows several gaps in knowledge, especially in insular regions where a confined population of animals and parasites co-exists. In this study was assessed the parasitism by endoparasite gastrointestinal in feral cats (n = 37) and rodents (n = 30) from the Fernando de Noronha Archipelago; in addition, the risk of human infection and ecological implications of these findings were discussed. Out of all samples analysed, 100% scored positive for the presence of gastrointestinal parasites in both feral cats and rodents. A total 17 genera and/or species of endoparasite gastrointestinal were identified, Ancylostoma sp., Strongyloides sp., Trichuris campanula and Toxocara cati were the parasites more frequently in feral cats. In rodents Eimeria sp., Strongyloides sp. and Trichuris muris were parasites more frequently herein detected. Human population living in this area are at risk of parasite infections due to the population of rodents and feral cats in the archipelago.


2005 ◽  
Vol 49 (9) ◽  
pp. 3794-3802 ◽  
Author(s):  
Manzour Hernando Hazbón ◽  
Miriam Bobadilla del Valle ◽  
Marta Inírida Guerrero ◽  
Mandira Varma-Basil ◽  
Ingrid Filliol ◽  
...  

ABSTRACT Mutations at position 306 of embB (embB306) have been proposed as a marker for ethambutol resistance in Mycobacterium tuberculosis; however, recent reports of embB306 mutations in ethambutol-susceptible isolates caused us to question the biological role of this mutation. We tested 1,020 clinical M. tuberculosis isolates with different drug susceptibility patterns and of different geographical origins for associations between embB306 mutations, drug resistance patterns, and major genetic group. One hundred isolates (10%) contained a mutation in embB306; however, only 55 of these mutants were ethambutol resistant. Mutations in embB306 could not be uniquely associated with any particular type of drug resistance and were found in all three major genetic groups. A striking association was observed between these mutations and resistance to any drug (P < 0.001), and the association between embB306 mutations and resistance to increasing numbers of drugs was highly significant (P < 0.001 for trend). We examined the association between embB306 mutations and IS6110 clustering (as a proxy for transmission) among all drug-resistant isolates. Mutations in embB306 were significantly associated with clustering by univariate analysis (odds ratio, 2.44; P = 0.004). In a multivariate model that also included mutations in katG315, katG463, gyrA95, and kasA269, only mutations in embB306 (odds ratio, 2.14; P = 0.008) and katG315 (odds ratio, 1.99; P = 0.015) were found to be independently associated with clustering. In conclusion, embB306 mutations do not cause classical ethambutol resistance but may predispose M. tuberculosis isolates to the development of resistance to increasing numbers of antibiotics and may increase the ability of drug-resistant isolates to be transmitted between subjects.


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