Identification of third stage larvae of strongyles and molecular diagnosis of Strongylus vulgaris in the feces of Thoroughbred horses kept in training centers in Rio de Janeiro, Brazil.

The aims of the present study were to identify strongyles in the feces of Thoroughbred horses based on larval morphology; to detect Strongylus vulgaris using molecular diagnosis and compare results to those of feces culture; and to determine the association between the presence of S. vulgaris with corresponding animal information (age range, gender, and anthelmintic use). Feces of horses kept in six Training Centers in Rio de Janeiro State, that showed the presence of ≥500 eggs per gram of feces (EPG) were subjected to strongyle identification. Of the 520 fecal samples collected, 35 had an EPG ≥ 500. After fecal culture for L3 larvae identification, DNA was extracted, subjected to PCR to amplify the ITS2 region DNA fragment of S. vulgaris, and sequenced. A total of 3500 larvae were analyzed. Most were classified as small strong (99.7%), with an emphasis on the type A subfamily of Cyathostominae. Forms of S. vulgaris only corresponded to 0.2%. In all, 25 samples showed amplified S. vulgaris DNA products and 11 showed nucleotide sequences with high sequence identity. Fecal culture and PCR results showed poor agreement (kappa = 0.105) for S. vulgaris diagnosis. Age, gender, anthelmintic use, and anthelmintic administration interval were not statistically significant. The present study showed the presence of S. vulgaris in the feces of horses kept in Rio de Janeiro Training Centers, mainly seen via PCR, which has emerged as the most effective tool for diagnosis. This study made it possible to identify strongyles that infect horses in the region, emphasizing upon the necessity for constant monitoring of the animals.

Geographic expansion of Fasciola hepatica (Linnaeus, 1758) due to changes in land use and cover in Brazil.

Fasciolosis is caused by parasites of the genus Fasciola, affecting animals and humans worldwide. In South America, the disease is a result of infection with Fasciola hepatica and although animal infections are more frequently reported, the full extent of the impact on human health due to underdiagnosis remains uncertain. This study analyzed changes in land use and the distribution of F. hepatica in bovine livers in Brazil over 18 years. Data on land use and land cover were collected from the Mapbiomas Project. Data on 414,481,963 slaughtered cattle and condemned livers due to F. hepatica infection were obtained from 4,433 municipalities. Joinpoint analysis was used to study the time series, and the Susceptible-Infected-Recovered (SIR) model was utilized to explore the behavior of F. hepatica infection. In the North, pasture areas significantly increased (P = 0.000001), while forested areas decreased (P = 0.000001). The midwestern and northern regions concentrated the highest number (>290 million) of cattle slaughtered in Brazil. More than 2 million bovine livers were infected by F. hepatica. The infected cattle originated from 194 municipalities in 2002, increasing to 747 in 2020. We consider that the changes in land use and intense cattle transportation may have caused the expansion of F. hepatica. The SIR model analyzed the spread of the disease looking at all six biomes: Caatinga, Amazon Forest, Cerrado, Pantanal, Atlantic Forest, and Pampa. Moreover, this infection not only threatens the health of animals but is also a major concern to biodiversity and vulnerable human communities in South America. Emblematic biomes such as the Amazon basin already face challenges with logging, desertification, and loss of biodiversity. Therefore, strategies for mitigating infection should include controlling illegal pasture areas, establishing health inspections of animal transport, quarantine of newly arrived animals, and livestock zoning, as well as clear One Health policies.

First microscopic and molecular parasitological survey of Strongylus vulgaris in Brazilian ponies.

The frequency of gastrointestinal parasites with an emphasis on Strongylus vulgaris was investigated among the Brazilian Pony breed kept on farms in the municipality of Teresópolis, state of Rio de Janeiro. Fecal samples were collected in three stud farms: A (n= 22 animals), B (n= 3), and C (n= 2). Fecal samples were subjected to the quantitative Mini-FLOTAC technique, using three different solutions, and to qualitative techniques. The parasite prevalence was found to be 81.4%. Eggs from strongylids were identified in 74% of the ponies. Eggs of Parascaris spp. were detected in 22.7% of the animals, which were all females of farm A. At this locality, mares were kept with their foals in fenced paddocks all the time. The NaCl solution of d = 1.200 g/ml was generally the one that presented the highest frequency of diagnosis of nematode eggs and the highest mean of fecal eggs per gram. The fecal samples were also subjected to the polymerase chain reaction for amplification of DNA from the ITS2 region for Strongylus vulgaris. Twelve samples presented nucleotide sequences for S. vulgaris. In the end, this study revealed the high frequency (96.3%) of S. vulgaris among ponies on farms in Teresópolis, Rio de Janeiro, Brazil.

A systematic review of honey bee (Apis mellifera, Linnaeus, 1758) infections and available treatment options.

BACKGROUND: Honey bees and honeycomb bees are very valuable for wild flowering plants and economically important crops due to their role as pollinators. However, these insects confront many disease threats (viruses, parasites, bacteria and fungi) and large pesticide concentrations in the environment. Varroa destructor is the most prevalent disease that has had the most negative effects on the fitness and survival of different honey bees (Apis mellifera and A. cerana). Moreover, honey bees are social insects and this ectoparasite can be easily transmitted within and across bee colonies. OBJECTIVE: This review aims to provide a survey of the diversity and distribution of important bee infections and possible management and treatment options, so that honey bee colony health can be maintained. METHODS: We used PRISMA guidelines throughout article selection, published between January 1960 and December 2020. PubMed, Google Scholar, Scopus, Cochrane Library, Web of Science and Ovid databases were searched. RESULTS: We have collected 132 articles and retained 106 articles for this study. The data obtained revealed that V. destructor and Nosema spp. were found to be the major pathogens of honey bees worldwide. The impact of these infections can result in the incapacity of forager bees to fly, disorientation, paralysis, and death of many individuals in the colony. We find that both hygienic and chemical pest management strategies must be implemented to prevent, reduce the parasite loads and transmission of pathogens. The use of an effective miticide (fluvalinate-tau, coumaphos and amitraz) now seems to be an essential and common practice required to minimise the impact of Varroa mites and other pathogens on bee colonies. New, alternative biofriendly control methods, are on the rise, and could be critical for maintaining honey bee hive health and improving honey productivity. CONCLUSIONS: We suggest that critical health control methods be adopted globally and that an international monitoring system be implemented to determine honey bee colony safety, regularly identify parasite prevalence, as well as potential risk factors, so that the impact of pathogens on bee health can be recognised and quantified on a global scale.

Horse and donkey parasitology: differences and analogies for a correct diagnostic and management of major helminth infections.

In June 2022, at the XXXII Conference of the Italian Society of Parasitology, the parallels of the main endoparasitic infections of horses and donkeys were discussed. Although these 2 species are genetically different, they can be challenged by a similar range of parasites (i.e. small and large strongyles, and Parascaris spp.). Although equids can demonstrate some level of resilience to parasites, they have quite distinct helminth biodiversity, distribution and intensity among different geographical locations and breeds. Heavily infected donkeys may show fewer clinical signs than horses. Although parasite control is primarily provided to horses, we consider that there may be a risk of drug-resistance parasitic infection through passive infection in donkeys when sharing the same pasture areas. Knowing the possible lack of drug efficacy (<90 or 80%), it is advocated the use of selective treatment for both species based on fecal egg counts. Adult horses should receive treatment when the threshold exceeds 200­500 eggs per gram (EPG) of small strongyles. Moreover, considering that there are no precise indications in donkeys, a value >300 EPG may be a safe recommendation. We have highlighted the main points of the discussion including the dynamics of helminth infections between the 2 species.

l-carvone decreases breast cancer cells adhesion, migration, and invasion by suppressing FAK activation.

Breast cancer is one of the most common types of cancer in the world and current therapeutic strategies present severe drawbacks. l-carvone (CRV), a monoterpene found in Mentha spicata (spearmint), has been reported to have potent anti-inflammatory activity. Here, we examined the role of CRV in breast cancer cell adhesion, migration and invasion in vitro and how this component could suppress the growth of Ehrlich carcinoma-bearing mice. In vivo, treatment with CRV significantly decreased tumor growth, increased tumor necrosis area, and reduced the expression of VEGF and HIF-1α in Ehrlich carcinoma-bearing mice. Furthermore, the anticancer efficacy of CRV was similar to currently used chemotherapy (Methotrexate), and the combination of CRV with MTX potentiated the chemotherapy effects. Further mechanistic investigation in vitro revealed that CRV modulates the interaction of breast cancer cells with the extracellular matrix (ECM) by disrupting focal adhesion, which was shown by scanning electron microscopy (SEM) and immunofluorescence. Moreover, CRV caused a decrease in ß1-integrin expression and inhibited focal adhesion kinase (FAK) activation. FAK is one of the most important downstream activators of several metastatic processes, including MMP-2 mediated invasion and HIF-1α/VEGF angiogenesis stimulus, both of which were found to be reduced in MDA-MB-231 cells exposed to CRV. Our results provide new insight about targeting ß1-integrin/FAK signaling pathway with CRV, which could be a new potential agent in the treatment of breast cancer.

A Systematic Review of Apicomplexa Looking into Epigenetic Pathways and the Opportunity for Novel Therapies.

Interest in host epigenetic changes during apicomplexan infections increased in the last decade, mainly due to the emergence of new therapies directed to these alterations. This review aims to carry out a bibliometric analysis of the publications related to host epigenetic changes during apicomplexan infections and to summarize the main studied pathways in this context, pointing out those that represent putative drug targets. We used four databases for the article search. After screening, 116 studies were included. The bibliometric analysis revealed that the USA and China had the highest number of relevant publications. The evaluation of the selected studies revealed that Toxoplasma gondii was considered in most of the studies, non-coding RNA was the most frequently reported epigenetic event, and host defense was the most explored pathway. These findings were reinforced by an analysis of the co-occurrence of keywords. Even though we present putative targets for repurposing epidrugs and ncRNA-based drugs in apicomplexan infections, we understand that more detailed knowledge of the hosts' epigenetic pathways is still needed before establishing a definitive drug target.

Genome-wide association study in thoroughbred horses naturally infected with cyathostomins.

Cyathostomins are considered one of the most important parasites of horses. A group of horses within a herd can be responsible for eliminating the majority of parasite eggs. This phenotype might be explained by genetic factors. This study aimed to identify genomic regions associated with fecal egg count (FEC) and hematological parameters by performing a genomic-wide association study (GWAS) in Thoroughbred horses naturally infected with cyathostomins. Packed cell volume (PCV), differential leukocyte, and FEC were determined from 90 horses. All animals were genotyped using the Illumina Equine 70 K BeadChip panel containing 65,157 SNP markers. The five genomic windows that have explained the highest percentage of the additive genetic variance of a specific trait (top 5) were further explored to identify candidate genes. A total of 33, 21, 30, 21, and 19 genes were identified for FEC, PCV, eosinophils, neutrophils, and lymphocyte count, respectively. The top 5 marker regions explained 2.86, 2.56, 2.73, 2.33, and 2.37% of the additive genetic variation of FEC, PCV, eosinophils, neutrophils, and lymphocytes count, respectively. This is the first study correlating phenotypic horse health traits to GWAS analysis, which may be used for animal breeding activities, reducing losses due to parasite infections.

Allium sativum extract against free-living larvae of Rhipicephalus microplus: a potential environmental biocontrol.

The infestation of Rhipicephalus microplus (Acari: Ixodidae) (Canestrini, 1887) represents a significant health problem for cattle. Up until today, no consistent control has been recommended for the free-living larval stage of R. microplus. The objective of the present study was to determine the larvicidal effect of an Allium sativum (garlic) aqueous extract against R. microplus using the larval package test, LPT. Tick larvae were obtained from adult female ticks from naturally infected animals, and 200 larvae were exposed to each A. sativum extract concentration (5, 7, 10, 16, 25, and 50%). All garlic groups received the extract in three different volumes (2, 5, and 7 ml) to determine the levels of humidity that would affect the free-living stage. Larvae from the control group were treated with distilled water and the positive control used cypermethrin in a 5-ml volume. Live and dead larvae were determined after 24 h of exposure. There was a significant statistical difference (P = 0.041) at 5% between 2 and 5 ml and between 7 and 10% of the extract using 2 ml (P = 0.034). There was a significant larvicidal activity of 100% mortality for the 16, 25, and 50% concentrations for all volumes. We observed a clear concentration-dependent effect for the extracts with a correlation coefficient of R2 > 0.92. The lethal concentration of 50% (LC50) was 13.6, 9.8, and 7.6% for the 2, 5, and 7 ml. The present A. sativum solutions may be considered a viable biofriendly alternative to reduce the number of the free-living larval stage of R. microplus on pasture and the consequent reduction of cattle infestation due to its high larval mortality.

Comparative study of antioxidant properties of the extracts of Polygonum acre H.B.K

SUMMARY Aims: This study aimed to characterize and compare the antioxidative potential of extracts obtained by infusion, decoction, tincture, aqueous extraction, and hydro-ethanolic maceration from the aerial parts of Polygonum acre H.B.K., which has been traditionally used in herbal preparations, for different purposes. The therapeutic benefits are attributed to phenolic compounds and their antioxidant properties. Methods: All extracts were characterized considering their quantitative content of the total phenolics, flavonoids, condensed and, hydrolysable tannins, by colori-metric methods. EHW-PA was selected for HPLC analysis as it showed a higher yield (10.58 % w/m) and a phenolic content > 200 mg GAE/g dry extract. The phenolic profile showed a chromatogram with 20 peaks, and the presence of gallic acid, rutin, and quercetin was verified by comparison with the retention times of standard compounds. The antioxidant activities were determined by ABTS capture test, ferric reducing antioxidant power test (FRAP), and the superoxide anion scavenging test. Results: Tinctures showed a higher average content of phenolic compounds, present mainly as flavonoid content. A significant correlation coefficient was observed between the total phenolic content and its antioxidant activity, determining by ABTS and FRAP assays. Differently, a low to moderate correlation between the flavonoid content and antioxidant activity was verified. Conclusion: This study reinforces the ethnopharmacological relevance of the Polygonum genus and could contribute to the scientific basis for the use of P. acre preparations.

Objetivos: Este estudio tuvo como objetivo caracterizar y comparar el potencial antioxidante de extractos obtenidos por infusión, decocción, tintura, extracción acuosa e hidroetanólica de las partes aéreas de Polygonum acre H.B.K., que se ha utilizado tradicionalmente en preparaciones a base de hierbas, para diferentes fines. Los beneficios terapéuticos se atribuyen a los compuestos fenólicos y sus propiedades antioxidantes. Métodos: Todos los extractos se caracterizaron considerando su contenido cuantitativo de fenólicos totales, flavonoides, taninos condensados e hidrolizables, por métodos colorimétricos. Se seleccionó EHW-PA para el análisis de HPLC ya que mostró un rendimiento más alto (10,58% m/m) y un contenido fenólico > 200 mg GAE/g de extracto seco. El perfil fenólico mostró un cromatograma con 20 picos y se verificó la presencia de ácido gálico, rutina y quercetina por comparación con los tiempos de retención de los compuestos estándar. Las actividades antioxidantes se determinaron mediante la prueba de captura ABTS, la prueba del poder antioxidante reductor férrico (FRAP) y la prueba de eliminación del anión superóxido. Resultados: Las tinturas mostraron un mayor contenido promedio de compuestos fenólicos, presentes principalmente como contenido de flavonoides. Se observó un coeficiente de correlación significativo entre el contenido fenólico total y su actividad antioxidante, determinado por ensayos ABTS y FRAP. De manera diferente, se verificó una correlación de baja a moderada entre el contenido de flavonoides y la actividad antioxidante. Conclusión: Este estudio refuerza la relevancia etnofarma-cológica del género Polygonum y podría contribuir a la base científica para el uso de preparaciones de P. acre.

Objetivos: O presente estudo teve como objetivo caracterizar e comparar o potencial antioxidante de extratos obtidos por infusão, decocção, tintura, extração aquosa e maceração hidroetanólica da parte aérea de Polygonum acre H.B.K., tradicional- mente utilizado em preparações fitoterápicas, para diversos fins. Os benefícios terapêuticos são atribuídos aos compostos fenólicos e suas propriedades antioxidantes. Métodos: Todos os extratos foram caracterizados quanto ao teor quantitativo de fenólicos totais, flavonoides, taninos condensados e hidrolisáveis, por métodos colorimétricos. O EHW-PA foi selecionado para análise por HPLC por apresentar maior rendimento (10,58% m/v) e conteúdo fenólico > 200 mg GAE/g de extrato seco. O perfil fenólico apresentou cromatograma com 20 picos, e a presença de ácido gálico, rutina e quercetina foi verificada pela comparação com os tempos de retenção dos compostos padrão. As atividades antioxidantes foram determinadas pelo teste de captura do radical ABTS, ensaio do potencial antioxidante por redução férrica (FRAP) e teste de desativação do ânion superóxido. Resultados: As tinturas apresentaram maior teor médio de compostos fenólicos, presentes, principalmente, na forma de flavonoides. Foi observado um coeficiente de correlação significativo entre o conteúdo fenólico total e sua atividade antioxidante, determinado pelos ensaios de ABTS e FRAP. Diferentemente, verificou-se uma correlação baixa a moderada entre o conteúdo de flavonoides e a atividade antioxidante. Conclusão: Este estudo reforça a relevância etnofarmacológica do gênero Polygonum e pode contribuir para a fundamentação científica do uso de preparações de P. acre.

Acaricidal effect of major compounds to control Rhipicephalus microplus (Canestrini, 1887) in dairy cows and possible alternatives for reversing multidrug resistance.

Tick control represent a great challenge to animal health. The objective of this study was to evaluate the efficacy of acaricidal compounds against Rhipicephalus microplus from dairy cattle systems in Paraná State, Brazil. Six farms (PR1-PR6) were selected, where anti-tick products were applied at fixed intervals. Two other farms that adopted alternative protocols; target selective treatment (PRS), and individual-based agroecological protocol (PRA) were also included in the trial. Fully engorged R. microplus were collected for the in vitro adult immersion test (AIT), and the egg hatch test (EHT) in all eight populations. The larval packet test (LPT) was used on PR6 and PRA tick populations. The treatment groups were composed of G1: dichlorvos 45% plus cypermethrin 5%, G2: deltamethrin 2.5%, G3: cypermethrin 15%, chlorpyriphos 25%, plus citronellal 1%, and G4: amitraz 12.5%. The efficacy at PR1 to PR6 revealed that G3 and G4 achieved moderate to high efficacy, from 75.0 to 100.0% and 73 to 98%, respectively. In the LPT, the efficacy at PR6 was 76.0, 67.0, 93.0 and 30.6%, while PRA presented 100.0, 100.0, 100.0, and 54.0%, for G1, G2, G3 and G4, respectively. Sustainable parasite control strategies are discussed.

Macrocyclic lactone resistance in nematodes of cattle in Brazil: Blame it to the ticks!

Strategic helminth control in adult cattle would hardly impose sufficient selection pressure to parasite populations but reports of resistance against macrocyclic lactone (ML) based-products have been confirmed worldwide. The objective of this study was to evaluate the scientific literature of ML resistance (< 90.0% efficiency) in helminths of cattle from 2001 (the first report) to 2020 in Brazil. Additional to the data, we studied the correlation of parasite control practices based on a questionnaire given to 32 farmers. The search returned 246 reports and 21 full articles were selected. From these, a Wordcloud and a Keyword Co-occurrence Network graph were created. The published data revealed that most of the studies (19/21) reported multi-species (Cooperia spp., Haemonchus sp., Oesophagostomum radiatum, Trichostrongylus sp.) resistance to ML. None of the reports described the treatment frequency in the tested farms. As for the questionnaire, the majority of farmers (> 70.0%) responded that they rotate products after treatment, animals are treated monthly or biweekly (58.0%), treatments are based on visual evaluation (coat condition, ectoparasite infestation), and that in 94.0% of the times farmers treat all animals. Moreover, farmers use ML in association with potent acaricides (cypermethrin, chlorpyriphos, fluazuron) in more than 90.0% of the times (15/16). It was observed that this regimen was used to prevent and control the cattle-tick Rhipicephalus microplus (90.0%) and the horn-fly, Haematobia irritans (30.0%) infestations. We conclude that the most important factor for nematode resistance was the high level of ML exposure of up to 16 times/year, in combination with acaricides to control ticks and to a lesser extent to control horn-flies. Therefore, selection of helminth populations in cattle in Brazil can be considered secondary to ectoparasite control. The present analysis is critical, as one the most widespread recommendations to avoid drug resistance is to reduce the use of long-acting compounds, due to their extended persistent periods, increasing parasite selection. Moreover, a more serious attitude must be taken regarding parasite control strategies for livestock, reinforcing that health protocols should be based on single acaricidal products whenever possible. Complementary, selective evaluations based on transient threshold population abundance must be enforced to reduce treatment frequency, reducing parasite selection and animal distress.

Suppressive treatment with monepantel and the fast selection for phenotypically resistant trichostrongylids of sheep.

Gastrointestinal parasite control has been a major challenge to livestock due to the failure of anthelmintic treatments. Monepantel (MNT) was introduced in 2009 as an alternative treatment option showing a new mechanism of action against nematode parasites. To study the response of MNT in a suppressive regime, 45-Suffolk and White Dorper naturally infected sheep were divided into one of three groups, G1: control ­ with no treatment, G2: MNT at 2.5 mg kg−1 live weight (LW) PO every 30 days, and G3: MNT at 4.0 mg kgLW−1 PO every 30 days for 6 months. Every 15 days, the animals were individually weighed (body weight, BW) and checked for Famacha (FMC) and body condition score (BCS). The efficacy of MNT was evaluated weekly by fecal egg count (FEC) every month. FEC showed >97% efficacy at the start of the experiment, revealing a significant reduction for G2 (28%) and G3 (39%) in the following months. There was no treatment, BW or BCS effect between treatments; however, there was a period (P < 0.0001) and a treatment vs period interaction (P < 0.0001) for BW. The data revealed that MNT at a therapeutic and suppressive dose had a non-linear polynomial efficacy regression (R2) of 0.988 and 0.992, respectively. This original experiment demonstrates how short-interval and suppressive MNT treatments would rapidly select Haemonchus contortus, showing a fast susceptible-resistance phenotypic population replacement. Therefore, it is suggested that MNT might be carefully used in parasite control programmes alongside other management strategies (i.e. FMC, BCS) to reduce treatment frequency and the selection process for resistance.

In vitro anthelmintic activity of an aqueous extract of Glycyrrhiza glabra and of glycyrrhetinic acid against gastrointestinal nematodes of small ruminants.

This study evaluated the in vitro anthelmintic activity of a liquorice (Glycyrrhiza glabra) root aqueous extract and of glycyrrhetinic acid at 30, 10, 5, 1, and 0.5 mg/mL against sheep gastrointestinal nematodes (GINs), using the egg hatch test (EHT), the larval development test (LDT), and the larval migration inhibition test (LMIT). The compounds were applied on a mixture of GIN eggs and larvae, mainly Trichostrongylus spp. and Teladorsagia/Ostertagia spp. Cytotoxicity assays were also performed. In the EHT, both candidates showed significant concentration-dependent efficacy and were significantly more effective (p < 0.001) at the highest concentrations (30 and 10 mg/mL) than the lowest ones. In the LDT, only G. glabra showed a concentration-dependent effect (R2 = 0.924), but glycyrrhetinic acid (R2 = 0.910) had significantly higher efficacy than G. glabra root extract. Moreover, the efficacy of glycyrrhetinic acid at 30, 10, and 5 mg/mL was significantly higher (p < 0.001) than at lower concentrations. In the LMIT, G. glabra showed concentration-dependent efficacy (R2 = 0.971), while considerably reduced efficacy was observed for glycyrrhetinic acid (R2 = 0.855) at the lowest concentrations. These data suggest that the two compounds may have different mechanisms of action. In the LMIT, the 50% lethal concentration (LC50) of glycyrrhetinic acid (~5.12 mg/mL) was > 2.0-fold lower when compared to G. glabra (12.25 mg/mL). Analysis and previous findings indicated low toxicity for both compounds. The results obtained encourage in vivo studies aimed at evaluating the potential use of the tested compounds as natural de-wormers in ruminants.

TITLE: Activité anthelminthique in vitro d'un extrait aqueux de Glycyrrhiza glabra et de l'acide glycyrrhétinique contre les nématodes gastro-intestinaux des petits ruminants. ABSTRACT: Cette étude a évalué l'activité anthelminthique in vitro d'un extrait aqueux de racine de réglisse (Glycyrrhiza glabra) et de l'acide glycyrrhétinique à 30, 10, 5, 1 et 0,5 mg/mL contre les nématodes gastro-intestinaux (NGI) du mouton, en utilisant le test d'éclosion des œufs (TEO), le test de développement larvaire (TDL) et le test d'inhibition de la migration larvaire (TIML). Les composés ont été appliqués sur un mélange d'œufs et de larves de NGI, principalement Trichostrongylus spp. et Teladorsagia/Ostertagia spp. Des tests de cytotoxicité ont également été effectués. Dans le TEO, les deux candidats ont montré une efficacité concentration-dépendante significative et ont été significativement plus efficaces (p < 0,001) aux concentrations les plus élevées (30 et 10 mg/mL) qu'aux plus faibles. Dans le TDL, seul G. glabra a montré un effet concentration-dépendant (R2 = 0,924), mais l'acide glycyrrhétinique (R2 = 0,910) avait une efficacité significativement plus élevée que l'extrait de racine de G. glabra. De plus, l'efficacité de l'acide glycyrrhétinique à 30, 10 et 5 mg/mL était significativement plus élevée (P < 0,001) qu'à des concentrations plus faibles. Dans le TIML, G. glabra a montré une efficacité concentration-dépendante (R2 = 0,971), tandis qu'une forte réduction d'efficacité a été observée pour l'acide glycyrrhétinique (R2 = 0,855) aux concentrations les plus faibles. Ces données peuvent suggérer que les deux composés peuvent avoir des mécanismes d'action différents. Dans le TIML, la concentration létale à 50% (CL50) de l'acide glycyrrhétinique (~ 5,12 mg/mL) était > 2,0 fois inférieure à celle de G. glabra (12,25 mg/mL). L'analyse et les résultats précédents ont indiqué une faible toxicité pour les deux composés. Les résultats obtenus encouragent les études in vivo visant à évaluer l'utilisation potentielle des composés testés ici comme anthelminthique naturels chez les ruminants.

Cyathostomin fecal egg count and milk quality in dairy donkeys.

This study was performed to assess the possible relationship between gastrointestinal strongylid infections and milk quantity and quality in donkeys used for milk production. Individual fecal and milk samples were collected from 16 multiparous lactating jennies of Amiatina breed at their 6th month of lactation. Statistical analysis was carried out between strongylid eggs per gram of faeces (EPG) and milk parameters. All animals were found to shed cyathostomin eggs, with EPG ranging from 150 to 1900. A higher milk production was observed in animals showing an EPG< 250, but this result was statistically not significant. Conversely, significant higher concentrations of milk urea and pH values, and lower concentrations of milk lactose, were observed in jennies with an EPG >1000. In conclusion, results from this study suggest that cyathostomin EPG values > 1000 may affect milk quality in dairy donkeys. Considering the novelty of these findings, more data needs to be collected to determine EPG thresholds to be used as a good marker for parasite infections influencing milk performance and quality in donkeys.

Chemical characterization and in vitro anthelmintic activity of Citrus bergamia Risso and Citrus X paradisii Macfad essential oil against Haemonchus contortus Kirby isolate.

Haemonchus contortus, a blood-sucking parasite of small ruminants, produces very important economic losses in the productive sector. This abomasum parasite has become resistant to most commercial drugs worldwide, and alternatives to fight this problem are urgently needed. Essential oils (EO) are a complex mixture of volatile secondary metabolites, composed mainly by terpenoids and phenolic compounds, from plants that have several pharmacological properties, including anthelmintic activity. Particularly, citrus peel is a source of cold-pressed EO, where limonene is its major component, and can be used as an additional food component for ruminants. The aim of the present work was to determine the in vitro anthelmintic activity of EO from Citrus bergamia (EOB), C. x paradisii (EOG) and limonene against the benzimidazole-susceptible Kirby isolate of H. contortus, using the egg hatch test (EHT) and the exsheathed third stage larval motility test (XLMT) using a WMicroTracker equipment. Albendazole (ABZ) and monepantel (MON) were used as positive controls. The 50% inhibitory concentrations (IC50) in XLMT were 8.77 and 13.88 µg/ml for EOB and EOG respectively, after an incubation of 72 h. An interesting observation on XLMT resulted when the positive controls were tested on the same plate, but in different well of the EOB. The volatile components of the EO significantly influenced (P < 0.05) the percentage of larval motility, reducing values from 66.9 to 19.6% for ABZ, and from 72.8 to 33.7% for MON, when comparing the activity of positive controls in a control plate without EO. The in vitro anthelmintic activity of EOB and EOG shows that they could be interesting candidates for nematode control. It is still necessary additional studies against the adult stage of H. contortus in efficacy trials in infected animals to validate their anthelmintic activity.

Mentha villosa Hubs., M. x piperita and their bioactives against gastrointestinal nematodes of ruminants and the potential as drug enhancers.

Parasitic diseases caused by gastrointestinal nematodes (GIN) are responsible for a major impact on ruminant welfare. Although the available anthelmintics have a safe margin of toxicity to the animals, their indiscriminate use has increased the selection of resistant parasite populations. In this scenario, essential oils (EO) stand out as a promising ecofriendly therapeutic alternative against GIN. The objective of this work was to determine the effect of the EO of Mentha villosa Hubs (MVEO) collected in 2017 and 2018, M. x piperita (MPEO) and their main components, carvone and limonene, against the third stage larvae (L3) of Haemonchus spp. and Trichostrongylus spp. The solutions, including in nanoemulsion preparations, were tested in a range of concentrations using the larval migration inhibition test (LMIT). The EO and carvone were also tested in combination with nitroxynil (NTX) to determine their effect as drug enhancers (additive or synergy). MVEO/2017, MVEO/2018, MPEO and carvone showed 70.6 (73.4 mg/mL), 86.3 (74.9 mL/mL), 95.5 (143.6 mg/mL), and 88.2 % (38.3 mg/mL) efficacy against L3, respectively. Carvone alone had approximately a 3-fold higher efficacy when compared to its concentration in each EO: 68.8 % in MVEO/2017 and 83.9 % in MVEO/2018. Limonene did not show any significant effect on inhibiting L3 migration. The combination of MPEO and NTX, and carvone and NTX showed a statistically significantly (P <  0.05) synergic and additive effect, respectively, when compared to the isolated treatment. The nanoemulsion of MVEO/2017 at 0.367 mg/mL, inhibited L3 migration by 83.1 %, demonstrating to be highly effective (concentration ratio of 1:0.004), when compared to the MVEO/2017 (70.6 % at 73.4 mg/mL) extraction. The in vitro data from the combination of MPEO or carvone plus NTX suggest that these products can be considered for in vivo experiments against the most important GIN of ruminants as drug enhancers, possibly reducing the final concentration of NTX`. The efficacy of carvone was higher (EC50 = 1.96 mg/mL) than its expected efficacy, based on its concentrations on both EO. Therefore, this component does not need the entire EO composition to exert its L3 motility action. The remarkable efficacy demonstrated by the MVEO/2017/nanoemulsion (EC50 = 0.10 mg/mL), supports its potential to be a candidate to the next-generation therapy to alleviate clinical parasite infections and combat GIN resistant populations.

Health evaluation of donkeys: parasite control methods and a model for challenge infections / Avaliação sanitária de jumentos: métodos de controle parasitário e um modelo para o desafio das infecções

Donkeys, mules, and asses are domestic animals of worldwide distribution, found in all regions of Brazil. Although more health data is needed from these species, some sectors of today's society are exploring alternatives to use these animals for milk production and the use of donkeys in social events and onotherapy. Donkeys (Equus asinus) are used in many everyday activities, but the animals need better welfare conditions. Although it is well known that endoparasite infections (i.e. cyathostomins, Strongylus spp., Parascaris sp.) can harm the clinical condition of the animals, there are limited clinical and laboratory supporting data, including registered therapeutic drugs for their control. The objective of the present work was to review the existing literature about parasite infections of donkeys, including their clinical implications, and the drug efficacy test to help practitioners improve their health management programs. To assist with that, we have developed a questionnaire to identify the risk factors of donkey farming, which is presented here in English and in Portuguese. Lastly, the present article also includes an original simulation using the susceptible-infected-recovered (SIR) model with low, moderate, and severe scenarios to help visualize the risk of parasite infections. The SIR model was based on the disease condition of donkeys in Brazil, using transient interaction levels from 0.0015 to 0.0025, infectivity levels from 0.10 to 0.40, and distinct recovery rates (R) from 0.01 to 0.08. As milk production is an expanding new activity worldwide, we want to emphasize that the first comprehensive studies must take into account differences in animal age, breed, and body condition score, local climate, pasture quality, day of sampling, and the period of lactation within the lactation curve to measure the health condition of donkeys. (AU)

Jumentos, mulas e burros são animais domésticos de distribuição mundial, encontrados em todas as regiões do Brasil. Muito embora exista uma grande necessidade de produzir mais dados sobre estas espécies, atualmente alguns setores estão buscando alternativas de exploração para estes animais, como a produção de leite e o uso deles em atividades sociais e onoterapia. Jumentos (Equus asinus) participam de várias atividades sociais, porém os animais necessitam de melhores condições de manejo e bem-estar. Embora as endoparasitoses (ex. ciatostomíneos, Strongylus spp., Parascaris sp.) possam causar grave condição clínica para estes animais, dados clínicos e laboratoriais são escassos, incluindo a falta de produtos específicos para seu controle. O objetivo do presente trabalho foi revisar a literatura existente sobre infecções parasitárias em jumentos, incluindo as implicações clínicas e os testes de eficácia de drogas, visando auxiliar os profissionais e os seus programas de manejo sanitário.(AU)

Intestinal Strongyle Genera in Different Typology of Donkey Farms in Tuscany, Central Italy.

Intestinal strongyles are common helminths of donkeys, in which they may be responsible for disease and poor performance. This study aimed to identify intestinal strongyle genera in 55 naturally infected donkeys from three different farm typologies in Tuscany, central Italy, using morphological and metrical analysis of third stage larvae (L3) obtained from faecal cultures. Larvae were identified using two previous reported morphological identification keys. Moreover, eggs per gram (EPG) data were also evaluated to assess differences, if any, according to the farm typology, sex, and age of the examined donkeys. The results showed that small strongyles were prevalent in all donkey farms. In all examined farms, most (92-100%) of L3 were identified as cyathostomin species of the genera Cylicocyclus spp. and Cylicostephanus spp. Large strongyles of the genera Strongylus spp. and Triodontophorus spp., were identified at low percentage (8%), only in the single organic farm included in the study. A high agreement was observed between the two different morphometric keys used. No significant differences were found for EPG according to farm typology, and sex and age from the examined donkeys. This is the first report about genera identification of intestinal strongyles infecting donkeys in Tuscany, Italy.