Search Results (31)

Vermipsyllid parasitize the body surface of sheep, feeding on blood and transmitting diseases, causing severe economic losses to the livestock industry. An outbreak of sheep Vermipsyllid fleas in the mountain pastures of Xinjiang’s Altai region showed that several commonly used commercial anthelmintic drugs had poor therapeutic effects on the prevalent flea species. This study first conducted species identification of Vermipsyllid through morphological analysis of 200 female and 40 male specimens collected from the Altai region, followed by molecular biological identification of 6 randomly selected fleas (3 females and 3 males). Finally, pharmacodynamic experiments were performed to screen for highly effective anthelmintic drugs. Ninety Altai multiparous ewes infected with Vermipsyllid were divided into six groups (fifteen sheep per group): an untreated control group (Ctr), avermectin injection group (Group I), ivermectin injection group (Group II), moxidectin pour-on group (Group III), cypermethrin pour-on group (Group IV), and dichlorvos pour-on group (Group V), with a 14-day trial period. On Day 0, each group received a single treatment according to drug instructions and specified dosages. The number of fleas, flea population reduction rates, and cure rates were measured on Day 0, Day 3, Day 7, and Day 14 to screen for effective anthelmintic drugs. Results showed that unfed female and male fleas were grayish-brown. Engorged females reached 14.15 mm in size, appearing pale white or yellow, with their sterna maintaining the original size and shape despite abdominal distension. Female fleas had 20–21 segments on the labium, while males had 16–19 segments. The hind tibiae featured four notches, and each side of the tergite had 13 ± 1 cup-like indentations. Molecular biological identification indicated that the identified fleas belonged to D. ioffi (Vermipsyllidae, Dorcadia Ioff), showing 99.13% sequence similarity with D. ioffi from Xinjiang, China. In pharmacodynamic experiments, the number of D. ioffi in Groups IV and V decreased to zero on both Day 7 and Day 14, which was extremely significantly lower than other groups (p < 0.01). The flea population reduction rates in Groups IV and V reached 100% on both days. By Day 14, the cure rates of Groups I, II, and III were 0%, while those of Groups IV and V were 100%. Avermectin injection, ivermectin injection, and moxidectin pour-on showed poor anthelmintic effects, whereas cypermethrin and dichlorvos pour-on exhibited high anthelmintic activity against this flea species. Full article

Background: The COVID-19 pandemic necessitated the urgent exploration of therapeutic options, including drug repurposing. Anthelmintic drugs such as ivermectin and mebendazole have garnered interest due to their potential antiviral and immunomodulatory properties. However, conflicting evidence from randomized clinical trials (RCTs) necessitates a comprehensive meta-analysis to determine their efficacy and safety in COVID-19 management. Objective: This meta-analysis evaluates the clinical efficacy of ivermectin and mebendazole in treating COVID-19 by analyzing their impact on viral clearance, symptom resolution, hospitalization duration, and safety profiles. Methods: A systematic search of Scopus, PubMed, Embase, and the Cochrane Library was conducted following PRISMA guidelines to identify RCTs published up to February 2025. Eligible studies included adult patients with confirmed COVID-19 who received ivermectin or mebendazole compared with a placebo or standard of care. Data extraction and risk of bias assessment were performed using the Cochrane Risk of Bias Tool. Statistical heterogeneity was evaluated using the I² statistic, and pooled effect sizes were calculated for primary clinical outcomes. Results: Twenty-three RCTs (n = 12,345) were included, with twenty-one studies on ivermectin and two on mebendazole. The pooled analysis suggested no statistically significant improvement in viral clearance (p = 0.39), hospitalization duration (p = 0.15), or symptom resolution (p = 0.08) with ivermectin or mebendazole. However, individual studies indicated potential benefits, particularly for mebendazole, in reducing viral load and inflammation. Both drugs exhibited favorable safety profiles, with no significant increase in adverse events. Conclusions: The promising propensities observed in selected studies underscore the potential of ivermectin and mebendazole as adjunct therapies for COVID-19. With well-established safety profiles, immunomodulatory effects, and affordability, these drugs present strong candidates for further exploration. Advancing research through well-designed, large-scale RCTs will help unlock their full therapeutic potential and expand treatment options in the fight against COVID-19. Full article

Evaluating different tactics to mitigate the effects of gastrointestinal nematode infection in growing stocker cattle is essential to better understand opportunities to optimize cattle health and performance. Due to the potential development of anthelmintic resistance, parasitologists and industry stakeholders have proposed maintaining refugia in cattle populations and combination treatment as tactics to delay anthelmintic resistance yet limited large-scale field data are available for practitioners to make evidence-based decisions. The objective of this experiment was to compare the effects of extended-release eprinomectin injectable and doramectin injectable on growth and fecal shedding of parasites in stocker calves grazing with non-treated (refugia) cohorts. Steers (n = 995; 243.38 kg) were randomized to one of two experimental treatment groups on Day 0, extended-release eprinomectin (ERE) or doramectin injectable (DOR). A subset of animals (n = 47) was selectively not treated with an anthelmintic to maintain refugia (REF). Individual body weights were recorded on days 0, 105, and 130 to calculate average daily gain and overall body weight gain during each of those time periods. Fecal samples were collected per rectum from approximately 10% of the same animals in each group on days 0, 105, and 130. Mean fecal egg count was significantly lower in the 10% of animals tested in the ERE group on days 105 and 130 when compared to 10% of the animals in the DOR group (Day 105—ERE: 46.45 eggs per gram, DOR: 155.30 eggs per gram, p < 0.01; Day 130—ERE: 9.65 eggs per gram, DOR: 22.51 eggs per gram, p = 0.02). From day 0 to 105, the mean average daily gain in the ERE group was 0.87 kg/day, which tended (p = 0.055) to be higher than the mean for the DOR group, 0.845 kg/day. Full article

Introduction: Grazing dairy ewes are often heavily challenged by parasitic infections, which represent one of the most important concerns in sheep farming due to their impacts on dairy sheep production. Objectives: The objectives of the present study were (i) to compare the short (i.e., albendazole) and long (i.e., eprinomectin) persistent effect of these anthelmintics in reducing infections by gastrointestinal nematodes (GIN) in ewes and (ii) to determine these effects on milk yield and quality in naturally infected with GIN dairy ewes. Methods: On each farm, 40 selected ewes were divided into four similar groups on Day 0 based on their fecal egg counts (eggs per gram of feces; epg) as follows: Group 1—control group; Group 2—albendazole-treated group; Group 3—pour-on eprinomectin-treated group; Group 4—injectable eprinomectin-treated group. Fecal egg counts and coprocultures were performed on Days 0, 15, 30, 45, 60 and 75. The milk yield and milk quality (i.e., fat and protein concentration and somatic cell counts) were estimated on the aforementioned occasions. Results: Eprinomectin outperformed albendazole in treating gastrointestinal nematode infections in dairy ewes. Both pour-on and injectable eprinomectin formulations provided long-lasting protection by reducing fecal egg counts (i.e., from 92.1% to 99.9%). Furthermore, eprinomectin-treated ewes exhibited increased daily milk yield and improved milk composition in terms of fat and protein concentrations and somatic cell counts. Conclusions: These findings highlight the benefits of long-persistent efficacy of eprinomectin as a preferred anthelmintic treatment for lactating dairy ewes, offering enhanced productivity and milk quality, while addressing parasite resistance concerns. Full article

There are numerous challenges associated with helminth control in captive animals. The aim of the present paper is to provide an overview of the research on deworming of captive herbivorous mammals, the associated problems and the solutions sought, in order to derive recommendations for practice in the relevant institutions. The research was conducted by searching electronic internet databases and following the bibliographies in the published articles. The articles found are presented in summarized form. Most of the results relate to herbivores of the family Bovidae, followed by the families Cervidae, Equidae, Elephantidae, Camelidae and Giraffidae. Systematic data are presented on the types of anthelmintics used, dosages and application regimens for different animal species. Anthelmintics were administered at doses similar to or even higher than those used in farm animals, with no evidence of side effects. Treatment results often depended on the animal and parasite species. Incomplete cure, reinfection, and resistance to anthelmintics were the most common problems in the field. Based on the literature reviewed, the optimal prevention measures include the following: quarantine of newly arrived animals; daily or as intensive as possible cleaning of droppings; regular change of substrate in the enclosures; and monitoring of possible infections and their qualitative and quantitative composition (monthly or at least every two months). For treatments and monitoring effectiveness, recommendations include the following: individual assessment of the need for treatment; selective choice of anthelmintics; post-treatment examination between the 10th and 14th day after deworming; carrying out a group treatment after a preliminary drug effect test; conducting mass deworming only in case of a significant increase in fecal egg counts, highly pathogenic helminth species and a deterioration in the condition of the animals. In the future, more attention should be paid to new approaches such as biological control by saprophytic fungi or natural compounds as an alternative to anthelmintics. This would help minimize the use of anthelmintics, protect refugia and allow animals to remain healthy by maintaining a balance with the low levels of parasites present. Full article

Soil-transmitted helminths (STHs) are a group of parasites that are globally distributed and are the most prevalent neglected disease (NTD) in Latin America and the Caribbean (LAC); their presence is associated with health and development problems. In Argentina, their distribution is heterogenous, and there are highly endemic areas in the north of the country. The World Health Organization (WHO) recommends the mass deworming of children as a first-line strategy for the prevention and control of STHs and recently also encourage the development of more sensitive diagnostic tests. The aim of this study was to determine the prevalence of STHs in Tartagal (Salta, Argentina) after four years of deworming interruption with albendazole and ivermectin. A total of 437 fecal samples were analyzed using standard coprological techniques, a subset of which were selected to molecularly typify protozoan parasites; 257 blood samples were analyzed for the presence of specific antibodies to the STH Strongyloides stercoralis. The most prevalent protozoan species were G. intestinalis (19.6–49.2%) and B. hominis (19.1–38.5%). Molecular characterization allowed us to evidence possible zoonotic or human-to-human transmission pathways for Giardia intestinalis or Blastocystis spp., while serology for S. stercoralis proved to be a useful screening tool for monitoring this parasite after treatment. In general, a decrease in the prevalence of STHs was observed in the area, from 60% to 2.9–20% for hookworms and from 51% to 1–9.3% for S. stercoralis four years after treatment, demonstrating the effectiveness and duration of anthelmintic treatment with these two drugs. Full article

Gastrointestinal nematodes are common in grazing sheep, but the intensity of the infection is not easily appreciated by farmers. For decades, they have relied on anthelmintic treatments to control these gastrointestinal nematodes. This has led to anthelmintic resistance and poor control of infection in most regions of the world. Using face-to-face semidirective interviews with farmers, we recorded their views on gastrointestinal nematode infection and its control. Ten organic and nine conventional meat sheep farmers from central France and 20 milk sheep farmers from the Basque region were interviewed and the data were analysed using a health model based on the importance of the disease and the barriers to implementing control. It was found that gastrointestinal nematodes were not the main health concern, and therefore farmers were not willing to invest too much time and money in their control. The conventional farmers relied on their veterinarians (the experts) to organise and select the anthelmintics, although they complained about the limited investment of their veterinarians in this matter. Organic farmers complained about their lack of knowledge about complementary and alternative medicines. Farmers rarely used faecal egg counts to build control of gastrointestinal nematodes and were unaware of the intensity of their infection. Knowledge of anthelmintic resistance was general (it exists) but farmers did not know if it existed on their farm. Resistance was often considered to have come from elsewhere, so the farmer did not feel at fault and did not take measures to prevent resistance. There is a need for all stakeholders to use faecal egg counts to assess the intensity of infection as well as the level of anthelmintic resistance to establish individual farm control programmes rather than standard blanket treatments. Full article

Gastrointestinal nematodes (GINs) are a major problem affecting sheep production systems worldwide. The flocks infected with GINs can undergo significant economic losses due to a decrease in productivity, the animals’ deaths, and the costs associated with treatments. The over-reliance on anthelmintics in the past years to eliminate GINs has resulted in the development of resistance against the available commercial anthelmintics. Genetically resistant animals can be used in mating systems to improve the overall flock resistance. This review aimed to summarize the estimated genetic parameters for resistance traits and genetic gains through the use of genetic/genomic selection for resistance to GINs in sheep. Heritability estimates from the literature ranged from 0.00 to 0.46 for fecal egg counts, 0.12 to 0.37 for packed cell volume/hematocrit, 0.07 to 0.26 for FAffa MAlan CHArt (FAMACHA©), from 0.10 to 0.37 for blood parameters, and 0.19 for Immunoglobulin A. Genetic correlations between traits measuring resistance to GINs and production traits ranged from negative to positive values in the literature. Genetic gains are possible when genetic/genomic selection for GIN resistance is applied. Therefore, genetic/genomic selection can be used to improve flocks’ resistance to GINs as a sustainable approach in sheep production systems. Full article

In Sweden, routine deworming has been used for several decades; however, to slow down the development of anthelmintic resistance, selective treatment is currently recommended. As part of a monitoring programme, equestrian premises submitted faecal samples to the National Veterinary Institute (SVA) twice per year between 2008 and 2017. Analyses for strongyles (small and large), tapeworms and ascarids, followed by premise-specific advice regarding deworming and parasite control strategies, were provided. In total, 43,330 faecal samples, collected from 26,625 horses on 935 premises in springtime (March to June), were analysed by quantitative or semi-quantitative flotation. Moreover, Strongylus vulgaris was detected by larval culture or PCR. Between 4 and 11% of individual horses tested positive for S. vulgaris and 3–10% were shedding tapeworm eggs. There were recurrent high and low egg shedders; 75% of horses with S. vulgaris appeared to have been recently introduced into the herd; the proportion of S. vulgaris-positive premises increased when individual samples rather than pooled samples were used. Based on the results of S. vulgaris diagnostics and strongyle egg-shedding level, 59% of the horses did not need to be dewormed. Full article

The anthelmintic resistance of gastrointestinal nematodes (GINs) poses a significant threat to sheep worldwide, but genomic selection can serve as an alternative to the use of chemical treatment as a solution for parasitic infection. The objective of this study is to conduct genome-wide association studies (GWASs) to identify single nucleotide polymorphisms (SNPs) in Rambouillet (RA) and Dorper × White Dorper (DWD) lambs associated with the biological response to a GIN infection. All lambs were genotyped with a medium-density genomic panel with 40,598 markers used for analysis. Separate GWASs were conducted using fecal egg counts (FECs) from lambs (<1 year of age) that acquired their artificial infections via an oral inoculation of 10,000 Haemonchus contortus larvae (n = 145) or naturally while grazing on pasture (n = 184). A GWAS was also performed for packed cell volume (PCV) in artificially GIN-challenged lambs. A total of 26 SNPs exceeded significance and 21 SNPs were in or within 20 kb of genes such as SCUBE1, GALNT6, IGF1R, CAPZB and PTK2B. The ontology analysis of candidate genes signifies the importance of immune cell development, mucin production and cellular signaling for coagulation and wound healing following epithelial damage in the abomasal gastric pits via H. contortus during GIN infection in lambs. These results add to a growing body of the literature that promotes the use of genomic selection for increased sheep resistance to GINs. Full article

Gastrointestinal nematodes (GINs) are a major health problem in tropical goat husbandry. The control of GIN has been nearly exclusively reliant on the use of anthelmintic treatments. Their wide use has provoked the appearance and diffusion of anthelmintic resistance. Therefore, there is a need to use anthelmintics only when they are really needed. This strategy of targeted selective treatment (TST) has been recommended. The selection of animals to be treated has been based either on the objective measures of GIN intensity (fecal nematode egg counts) performed in the laboratory or on indirect assessment such as anemia (FAMACHA©), diarrhea score or weight gains, particularly in sheep. The roughness of hair has also been proposed in goats. These indicators can be handled by the farmer. Their opinion on the importance of GINs, and the indicators that they are ready to accept and use have very rarely been studied. Goat for meat production is important in the French West Indies (especially in Guadeloupe) and GIN infection may significantly alter this production. Eighteen farmers participated in semi-directive interviews in order to appreciate their relation to goat GIN infection and the solutions they considered. Seventeen farms were investigated for fecal nematode egg counts, FAMACHA©, body score, and roughness of hair. The average infection by GINs was high (average fecal egg count 1562 and standard deviation 2028) with a wide range from one farm to another (from 0 to 25,000 eggs of GIN per gram of feces). The Haemonchus genera was predominant (54%), followed by Trichostrongylus (37%) and Oesophagostomum (9%). Young goats were less infected than adult goats since they were not yet grazing; males were more infected than females; and the Creole breed was more infected than the other breeds. Among the farming types, the professional ones were less infected compared with the traditional or mixed agriculture and husbandry farms. Those using targeted selective treatment did not have a significantly higher GIN infection than those treating the whole herd. Most of the characteristics were related and multivariate analysis could not match the intensity of GIN infection with any parameter. The frequency of anthelmintic treatments was negatively related to the use of body score, FAMACHA©, and hair roughness. The use of semi-directive interviews provided a wider understanding of the strategies and problems of farmers. The farmers valued their animals very much and diseases, in general, were a preoccupation, whereas parasites were not a major issue for traditional farmers. This is due to the important use of indicators and the belief in their value that gives comfort to the farmers that the parasites are being controlled. The extension services have well diffused the practice of indicators to the goat farmers of Guadeloupe, with some depending less on anthelmintics to control the gastrointestinal nematodes by using targeted selective treatments. Full article

Parasitic diseases are a major impediment to livestock production worldwide. However, knowledge about the epidemiology of gastrointestinal parasites in many low-income countries is still limited. An epidemiological survey on these parasites in traditionally reared cattle was performed in central Ethiopia (West Shewa Zone), from September 2019 to November 2021. Overall, 691 samples were analyzed qualitatively (flotation technique) and quantitatively (McMaster technique) to detect helminth eggs and Eimeria oocysts. Furthermore, coprocultures were conducted on pooled samples to identify the genera of gastrointestinal strongyles (GIS). The difference in prevalence according to agroecology, season, age, sex and body condition score (BCS) was investigated using univariable tests and through a multivariable logistic regression analysis, whereas abundance values were interpreted using a descriptive approach. The highest prevalence values were observed for GIS (50.2%) and Eimeria spp. (36.0%), whereas Moniezia spp. (16.3%), Strongyloides spp. (5.1%) and Schistosoma spp. (4.2%) showed lower values. Trichuris spp. and Toxocara vitulorum were sporadically found. A coproculture revealed that Haemonchus spp. (34.6%), Trichostrongylus spp. (25.9%) and Bunostomum spp. (19.1%) were the most frequent genera of GIS. A poor BCS was strongly associated with the occurrence of GIS, while seasonal variations were detected for Eimeria spp., GIS, Moniezia spp. and Schistosoma spp., with a higher prevalence and burden during the rainy season, and agroecology also strongly influenced different parasitic taxa. This present study increases the knowledge about the epidemiological features of gastrointestinal parasites in the context of a low-income country, suggesting a more tailored approach for their control. The use of a BCS as an indicator for the selective treatment of highly infested animals is supported by our findings, introducing a possible way to prevent anthelmintic resistance in areas where basic diagnostic services are rarely used by farmers. Full article

Trematode infections occur worldwide causing considerable deterioration of human health and placing a substantial financial burden on the livestock industry. The hundreds of millions of people afflicted with trematode infections rely entirely on only two drugs (praziquantel and triclabendazole) for treatment. An understanding of anthelmintic biotransformation pathways in parasites should clarify factors that can modulate therapeutic potency of anthelmintics currently in use and may lead to the discovery of synergistic compounds for combination treatments. Despite the pronounced epidemiological significance of trematodes, there is still no adequate understanding of the functionality of their metabolic systems, including xenobiotic-metabolizing enzymes. The review is focused on the structure and functional significance of the xenobiotic-metabolizing system in trematodes. Knowledge in this field can solve practical problems related to the search for new targets for antiparasitic therapy based on a focused action on certain elements of the parasite’s metabolic system. Knowledge of the functionality of this system is required to understand the adaptation of the biochemical processes of parasites residing in the host and mechanisms of drug resistance development, as well as to select a promising molecular target for the discovery and development of new anthelmintic drugs. Full article

Pancreatic ductal adenocarcinoma (PDAC) has one of the highest mortality rates and requires the development of highly efficacious medications that can improve the efficiency of existing treatment methods. In particular, in PDAC, resistance to conventional chemotherapy reduces the effectiveness of anticancer drugs, decreasing the therapeutic efficiency. Sphingosine 1-phosphate (S1P), produced by sphingosine kinase (SK), plays a vital role in cancer growth, metastasis, chemotherapy, and drug resistance. Focusing on the structural characteristics of mebendazole (MBZ), we studied whether MBZ would affect metastasis, invasion, and drug resistance in cancer by lowering S1P production through inhibition of SK activity. MBZ selectively inhibited SK1 more than SK2 and regulated the levels of sphingolipids. MBZ inhibited the proliferation and migration of cancer cells in other PDAC cell lines. To determine whether the effect of MBZ on cancer cell growth and migration is S1P-mediated, S1P was treated, and the growth and migration of cancer cells were observed. It was found that MBZ inhibited S1P-induced cancer cell growth, and MBZ showed a growth inhibitory effect by regulating the JAK2/STAT3/Bcl-2 pathway. The phosphorylation of focal adhesion kinase (FAK), a transcription factor that regulates migration, was inhibited by MBZ, so it was found that the effect of MBZ regulates the migration of cancer cells through the S1P/FAK/vimentin pathway. In conclusion, our study suggests that the anthelmintic MBZ can be used as a potential therapeutic agent for treating PDAC and for structural synthesis studies of its analogs. Full article

Vaccines are one of the most successful medical inventions to enable the eradication or control of common and fatal diseases. Environmental exposure of hosts, including helminth infections, plays an important role in immune responses to vaccines. Given that helminth infections are among the most common infectious diseases in the world, evaluating vaccine efficiency in helminth-infected populations may provide critical information for selecting optimal vaccination programs. Here, we reviewed the effects of helminth infections on vaccination and its underlying immunological mechanisms, based on findings from human studies and animal models. Moreover, the potential influence of helminth infections on SARS-CoV-2 vaccine was also discussed. Based on these findings, there is an urgent need for anthelmintic treatments to eliminate helminth suppressive impacts on vaccination effectiveness during implementing mass vaccination in parasite endemic areas. Full article