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Encalada-Mena L.,Autonomous University of Campeche | Tuyub-Solis H.,Autonomous University of Campeche | Ramirez-Vargas G.,National Research Center Disciplinaria en Parasitologia Veterinaria | Mendoza-de-Gives P.,National Research Center Disciplinaria en Parasitologia Veterinaria | And 2 more authors.
Veterinary Parasitology | Year: 2014

The aim of this study was to identify the presence of anthelmintic resistance to benzimidazole (BZ) in gastrointestinal nematodes (GIN) from naturally infected calves in the tropical regions of Campeche State of Mexico. The faecal egg count reduction test (FECRT) was conducted at 10 livestock farms localised in the Carmen, Candelaria, Champotón, Escárcega and Palizada municipalities of Campeche. The assessed anthelmintic was albendazole. The trial period was between August and November 2012. Infected calves were allocated into two groups, control and treated, on each farm. The number of eggs excreted per g of faeces was estimated by the McMaster technique at 0 and 14 days pre- and post- treatment, respectively. Recovered infective larvae (L3) (pre- and post-treatment) were identified using taxonomic keys and a genomic DNA (gDNA) template from a pool of L3 species prior to BZ treatment. Additionally, BZ-resistance polymorphisms in Haemonchus were determined by Allele Specific PCR (AS-PCR) at codon 200 and by end-point PCR at codons 200, 198 and 167 from isotype 1 of the β-tubulin gene. Morphological identification revealed Haemonchus, Cooperia, Trichostrongylus, Ostertagia and Oesophagostumum L3 species before BZ treatment, and Haemonchus and Cooperia L3 species after treatment. Additionally, of the GIN populations, three exhibited BZ resistance, and seven were BZ-susceptible by FECRT. Molecular analysis identified mutations in Haemonchus populations on nine farms at codon 200 (TTC to TAC) by AS-PCR, while no changes were observed at 167 (TTC to TAC) or 198 (GAA to GCA) codons in any population. In conclusion, resistance to BZ was determined in Haemonchus and Cooperia nematodes in infected cattle in five tropical regions of Campeche State. © 2014 Elsevier B.V.


PubMed | Metropolitan Autonomous University, National Research Center Disciplinaria en Parasitologia Veterinaria, Autonomous University of Baja California, University of Matanzas and 2 more.
Type: Journal Article | Journal: Tropical animal health and production | Year: 2016

Forty-five Pelibuey sheep were experimentally infested with nematodes to evaluate the effect of three free condensed tannin (FCT) levels of Lysiloma acapulcensis on fecal egg counts (FECs), packed cell volumes (PCV), ocular mucosa colors (OMC), average daily gain (ADG), and adult nematode count. Five treatments were used: 12.5, 25.0, and 37.5mg of FCT kg


Torres L.,Autonomous University of Tamaulipas | Almazan C.,Autonomous University of Tamaulipas | Ayllon N.,Institute Investigacion en Recursos Cinegeticos IREC CSIC UCLM JCCM | Galindo R.C.,Institute Investigacion en Recursos Cinegeticos IREC CSIC UCLM JCCM | And 4 more authors.
BMC Genomics | Year: 2011

Background: The horn fly, Haematobia irritans (Linnaeus, 1758) (Diptera: Muscidae) is one of the most important ectoparasites of pastured cattle. Horn flies infestations reduce cattle weight gain and milk production. Additionally, horn flies are mechanical vectors of different pathogens that cause disease in cattle. The aim of this study was to conduct a functional genomics study in female horn flies using Expressed Sequence Tags (EST) analysis and RNA interference (RNAi).Results: A cDNA library was made from whole abdominal tissues collected from partially fed adult female horn flies. High quality horn fly ESTs (2,160) were sequenced and assembled into 992 unigenes (178 contigs and 814 singlets) representing molecular functions such as serine proteases, cell metabolism, mitochondrial function, transcription and translation, transport, chromatin structure, vitellogenesis, cytoskeleton, DNA replication, cell response to stress and infection, cell proliferation and cell-cell interactions, intracellular trafficking and secretion, and development. Functional analyses were conducted using RNAi for the first time in horn flies. Gene knockdown by RNAi resulted in higher horn fly mortality (protease inhibitor functional group), reduced oviposition (vitellogenin, ferritin and vATPase groups) or both (immune response and 5'-NUC groups) when compared to controls. Silencing of ubiquitination ESTs did not affect horn fly mortality and ovisposition while gene knockdown in the ferritin and vATPse functional groups reduced mortality when compared to controls.Conclusions: These results advanced the molecular characterization of this important ectoparasite and suggested candidate protective antigens for the development of vaccines for the control of horn fly infestations. © 2011 Torres et al; licensee BioMed Central Ltd.


Almazan C.,Autonomous University of Tamaulipas | Lagunes R.,National Autonomous University of Mexico | Villar M.,Institute Investigacion en Recursos Cinegeticos | Canales M.,Institute Investigacion en Recursos Cinegeticos | And 5 more authors.
Parasitology Research | Year: 2010

The cattle ticks, Rhipicephalus (Boophilus) spp., affect cattle production in tropical and subtropical regions of the world. Tick vaccines constitute a cost-effective and environmentally friendly alternative to tick control. The recombinant Rhipicephalus microplus Bm86 antigen has been shown to protect cattle against tick infestations. However, variable efficacy of Bm86-based vaccines against geographic tick strains has encouraged the research for additional tick-protective antigens. Herein, we describe the analysis of R. microplus glutathione-S transferase, ubiquitin (UBQ), selenoprotein W, elongation factor-1 alpha, and subolesin (SUB) complementary DNAs (cDNAs) by RNA interference (RNAi) in R. microplus and Rhipicephalus annulatus. Candidate protective antigens were selected for vaccination experiments based on the effect of gene knockdown on tick mortality, feeding, and fertility. Two cDNA clones encoding for UBQ and SUB were used for cattle vaccination and infestation with R. microplus and R. annulatus. Control groups were immunized with recombinant Bm86 or adjuvant/saline. The highest vaccine efficacy for the control of tick infestations was obtained for Bm86. Although with low immunogenic response, the results with the SUB vaccine encourage further investigations on the use of recombinant subolesin alone or in combination with other antigens for the control of cattle tick infestations. The UBQ peptide showed low immunogenicity, and the results of the vaccination trial were inconclusive to assess the protective efficacy of this antigen. These experiments showed that RNAi could be used for the selection of candidate tick-protective antigens. However, vaccination trials are necessary to evaluate the effect of recombinant antigens in the control of tick infestations, a process that requires efficient recombinant protein production and formulation systems. © The Author(s) 2009.


Merino O.,Institute Investigacion en Recursos Cinegeticos IREC CSIC UCLM JCCM | Antunes S.,Institute Higiene e Medicina Tropical | Mosqueda J.,Autonomous University of Queretaro | Moreno-Cid J.A.,Institute Investigacion en Recursos Cinegeticos IREC CSIC UCLM JCCM | And 6 more authors.
Vaccine | Year: 2013

Tick-borne pathogens cause diseases that greatly impact animal health and production worldwide. The ultimate goal of tick vaccines is to protect against tick-borne diseases through the control of vector infestations and reducing pathogen infection and transmission. Tick genetic traits are involved in vector-pathogen interactions and some of these molecules such as Subolesin (SUB) have been shown to protect against vector infestations and pathogen infection. Based on these premises, herein we characterized the efficacy of cattle vaccination with tick proteins involved in vector-pathogen interactions, TROSPA, SILK, and Q38 for the control of cattle tick, Rhipicephalus (Boophilus) microplus infestations and infection with Anaplasma marginale and Babesia bigemina. SUB and adjuvant/saline placebo were used as positive and negative controls, respectively. The results showed that vaccination with Q38, SILK and SUB reduced tick infestations and oviposition with vaccine efficacies of 75% (Q38), 62% (SILK) and 60% (SUB) with respect to ticks fed on placebo control cattle. Vaccination with TROSPA did not have a significant effect on any of the tick parameters analyzed. The results also showed that vaccination with Q38, TROSPA and SUB reduced B. bigemina DNA levels in ticks while vaccination with SILK and SUB resulted in lower A. marginale DNA levels when compared to ticks fed on placebo control cattle. The positive correlation between antigen-specific antibody titers and reduction of tick infestations and pathogen infection strongly suggested that the effect of the vaccine was the result of the antibody response in vaccinated cattle. Vaccination and co-infection with A. marginale and B. bigemina also affected the expression of genes encoding for vaccine antigens in ticks fed on cattle. These results showed that vaccines using tick proteins involved in vector-pathogen interactions could be used for the dual control of tick infestations and pathogen infection. © 2013 Elsevier Ltd.


Torres-Acosta J.F.J.,Autonomous University of Yucatán | Molento M.,Federal University of Paraná | Mendoza de Gives P.,National Research Center Disciplinaria en Parasitologia Veterinaria
Veterinary Parasitology | Year: 2012

The widespread presence of anthelmintic resistant gastrointestinal parasitic nematodes in outdoor ruminant production systems has driven the need to identify and develop novel approaches for the control of helminths with the intention to reduce the dependence on commercial anthelmintic drugs. This paper identifies what has been done in Latin America (LA) in terms of estimating the prevalence of anthelmintic resistance (AR) in ruminant production systems and the application of different novel approaches for the control of helminths in those systems, including research and extension activities. Firstly, the paucity of knowledge of AR is discussed in the context of different countries, as well as, the available economic resources for research, the technical infrastructure available and the practical difficulties of the production systems. It is then proposed that the search for novel approaches is not only driven by AR but also by the need for techniques that are feasible for application by resource-poor farmers in non-commercial subsistence farming systems. However, the commercial benefits of these approaches are often limited and so are funding inputs in most countries. The workers participating in the research into different novel approaches are identified as well as the different methods being studied in the different areas of LA according to their published results. In addition, the difficulties experienced during extension efforts to reach farmers and help them to adopt novel approaches for the control of parasitic nematodes in LA are discussed. The role of regulatory authorities in these countries is discussed as some methods of control might need an official confirmation of their efficacy as well as authorization prior to application as they may affect animal products (i.e. residues) and/or impose a hazard for animal welfare. The role of the pharmaceutical companies is also discussed. © 2011 .


PubMed | Autonomous University of Queretaro, Instituto Nacional de Tecnologia Agropecuaria, National Research Center Disciplinaria en Parasitologia Veterinaria, U.S. Department of Agriculture and 2 more.
Type: | Journal: Veterinary parasitology | Year: 2016

Babesia bovis and Babesia bigemina are causative agents of bovine babesiosis, a tick-borne disease of cattle in tropical and subtropical regions. Babesia spp. infection adversely affects cattle health and can be fatal resulting in considerable economic loss worldwide. Under endemic stability conditions, herds contain high numbers of chronically infected, asymptomatic carrier animals, in which no parasitemia is detected by microscopic blood smear examination. In addition to bovines, also water buffaloes are infected by both Babesia spp. commonly leading to a subclinical infection. The infection rate (by nPCR) and herd exposure (by IFAT) of bovines and water buffaloes reared under similar field conditions in an area of endemic stability were determined and compared. In order to optimize direct parasite detection, highly sensitive nPCR assays were developed and applied, allowing the detection of as little as 0.1 fg DNA of each Babesia pathogen. Significantly lower percentages (p<0.001) of seropositive water buffaloes compared to bovines were observed for B. bovis (71.4% vs. 98%) and B. bigemina (85% vs. 100%). Interestingly, in comparison, differences noticed between water buffaloes and bovines were considerably larger with direct parasite detection by nPCR (16.2% vs. 82.3% and 24% vs. 94.1% for B. bovis and B. bigemina, respectively). As expected, bovines subjected to monthly acaricide applications exhibited a significant lower infection rate as determined by nPCR than bovines not subjected to these measures (B. bovis 33.3% vs. 90.7%, p<0.001; B. bigemina 80% vs. 96.5%, p<0.001, for treated vs. untreated animals). Interestingly no differences between these groups were observed with respect to seropositivity, suggesting similar rates of parasite exposure (B. bovis 100% vs. 97.7%, p<0.001; B. bigemina 100% vs. 100%, p<0.001). Importantly, a significantly higher number of water buffaloes as determined by nPCR were infected when reared jointly with bovines not subjected to tick control than when reared jointly with bovines subjected to tick control (B. bovis 31.6% vs. 9.5%, p<0.01; B. bigemina 42.1% vs. 9.5%, p<0.01, for water buffaloes reared with untreated vs. treated bovines) and/or when reared without bovines (B. bovis 31.6% vs. 11.6%, p<0.01; B. bigemina 42.1% vs. 20%, p<0.01). An accumulation of seropositivity and a decline of infection rates were observed in older animals, while differences observed with regard to gender may warrant further investigation. In summary, our findings suggest that water buffaloes are much more capable to limit or eliminate Babesia infection, possibly due to a more capable immune defense. Furthermore, an increased Babesia spp. parasite reservoir of bovines seems to increase the infection rate of water buffaloes when both are reared on the same pasture.


PubMed | Autonomous University of Yucatán, Colegio de Mexico, National Research Center Disciplinaria en Parasitologia Veterinaria and Autonomous University of the State of Morelos
Type: | Journal: Journal of helminthology | Year: 2016

Two groups of six Haemonchus contortus infected Saint Croix lambs each received different diets for 11 weeks: control group, commercial food, molasses and lucerne hay; and treated group, nutritional pellets (NPs) containing Duddingtonia flagrans at 2 106 chlamydospores/kg body weight (BW), sorghum and lucerne hay. Mean BW gain (BWG), body condition score (BCS) and packed cell volume (PCV) and also eggs/g of faeces (EPG) and recovered L3 were compared using a repeated measures across time model. Groups had similar BWG (control 139.7 0.035 g/day and treated 167.7 0.041 g/day), BCS (control 3.6 0.39 and treated 3.4 0.46) and PCV (control 32.5 1.68% and treated 30.0 1.68%). The mean EPG of the control group was 1215 1040 and in the treated group it was 2097.91 2050. No reduction in larval population was observed during weeks 2 and 3. The greatest larval population reduction in the faeces of treated lambs was observed during the first week (70.5%) and from weeks 6 to 11, with a mean value close to 70% (P < 0.05). In general, both experimental groups showed a similar feed conversion. It was concluded that both diets resulted in similar lamb growth, PCV, BCS and H. contortus EPG. However, NP consumption significantly reduced the H. contortus L3 population in lamb faeces.


Miranda-Miranda E.,National Research Center Disciplinaria en Parasitologia Veterinaria | Cossio-Bayugar R.,National Research Center Disciplinaria en Parasitologia Veterinaria | Martinez-Ibanez F.,Servicio Nacional de Sanidad | Bautista-Garfias C.R.,National Research Center Disciplinaria en Parasitologia Veterinaria
Medical and Veterinary Entomology | Year: 2011

Different laboratory cultures of the acarine tick Rhipicephalus (Boophilus) microplus (Canestrini, 1888) (Ixodida: Ixodidae) were infested by small Megaselia scalaris (Loew, 1866) (Diptera: Phoridae) flies. Larvae of this species exhibited opportunistic parasitism predominantly on engorged female ticks, causing severe damage to their cuticle through which the flies were able to reach R. microplus internal organs, on which they fed until developing into pupae in the tick's remains. The flies were kept by continuous propagation on fresh ticks over six generations during which the same parasitoid behaviour was observed. Here we report on an ixodid tick laboratory culture used for rearing M. scalaris. Medical and Veterinary Entomology © 2010 The Royal Entomological Society. No claim to original US government works.


PubMed | National Research Center Disciplinaria en Parasitologia Veterinaria
Type: Journal Article | Journal: Turkiye parazitolojii dergisi | Year: 2016

In the Mexican ethno-medicine, a number of plants have shown a successful anthelmintic activity. This fact could be crucial to identify possible green anti-parasitic strategies against nematodes affecting animal production. This research evaluated the in vitro and in vivo nematocidal effects of two single and combined plant extracts: bulbs of Allium sativum (n-hexane) and flowers of Tagetes erecta (acetone). The in vivo assay evaluated the administration of extracts either individually or combined against Haemonchus contortus in experimentally infected gerbils.The in vitro larvicidal activity percentage (LAP) of A. sativum and T. erecta extracts against H. contortus (L3) was determined by means of individual and combined usage of the extracts. Similarly, the extracts were evaluated in terms of reduction in the parasitic population in gerbils infected with H. contortus by individual and combined usage.The LAP at 40 mg/mL was 68% with A. sativum and 36.6% with T. erecta. The combination caused 83.3% mortality of parasites. The oral administration of A. sativum and T. erecta extracts at 40 mg/mL, caused 68.7% and 53.9% reduction of the parasitic burden, respectively. Meanwhile, the combined effect of both extracts shown 87.5% reduction.This study showed evidence about the effect of A. sativum and T. erecta plant extracts by means of individual and combined usage against H. contortus in in vitro and in vivo bioassays in artificially H. contortus-infected gerbils as a model.

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