Babesia: a world emerging

Babesia are tick-transmitted hemoprotozooans that infect mammals and birds, and which are acknowledged for their major impact on farm and pet animal health and associated economic costs worldwide. Additionally, Babesia infections of wildlife can be fatal if associated with stressful management practices; and human babesiosis, also transmitted by blood transfusion, is an increasing public-health concern. Due to the huge diversity of species reported to serve as Babesia hosts, all vertebrates might be potential carriers, as long as they are adequate hosts for Babesia-vector ticks. We here provide a comprehensive overview of the most relevant Babesia species, and a discussion of the classical taxonomic criteria. Babesia, Cytauxzoon and Theileria parasites are closely related and collectively referred to as piroplasmids. A possible scenario for the history of piroplasmids is presented in the context of recent findings, and its implications for future research avenues are outlined. Phylogenetic trees of all available 18S rRNA and hsp70 genes were generated, based on which we present a thoroughly revised molecular classification, comprising five monophyletic Babesia lineages, one Cytauxzoon clade, and one Theileria clade. Updated 18S rRNA and beta-tubulin gene trees of the B. microti isolates agree with those previously reported. To reconcile estimates of the origin of piroplasmids and ticks (∼300. Ma, respectively), and mammalian radiation (60. Ma), we hypothesize that the dixenous piroplasmid life cycle evolved with the origin of ticks. Thus, the observed time gap between tick origin and mammalian radiation indicates the existence of hitherto unknown piroplasmid lineages and/or species in extant vertebrate taxa, including reptiles and possibly amphibians. The development and current status of the molecular taxonomy of Babesia, with emphasis on human-infecting species, is discussed. Finally, recent results from population genetic studies of Babesia parasites, and their implications for the development of pathogenicity, drug resistance and vaccines, are summarized.Fil: Schnittger, Leonhard. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Patobiología; ArgentinaFil: Rodriguez, Anabel Elisa. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Patobiología; ArgentinaFil: Jacobsen, Monica Ofelia. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Patobiología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Morrison, David A.. Swedish University of Agricultural Sciences; Sueci

Standardization of the model of experimental infection in cattle with Anaplasma centrale for the production of immunogens

La anaplasmosis bovina es una enfermedad infecciosa transmisible causada por la rickettsia Anaplasma marginale. La profilaxis se puede lograr mediante la vacunación con eritrocitos infectados con A. centrale obtenidos a partir de terneros esplenectomizados. La estandarización de las condiciones para la infección de bovinos con A. centrale puede conducir a un sistema de producción eficiente, que es particularmente importante cuando la vacuna se produce como una formulación trivalente que también contiene eritrocitos infectados con formas atenuadas de los parásitos Babesia bovis y B. bigemina. En este estudio, se inocularon bovinos (n = 26) con diferentes dosis de eritrocitos infectados (EI) con A. centrale (2, 3, 4 o 5 x 108 EI por animal). El curso de la infección se analizó con respecto al período prepatente, la rickettsemia y la disminución del hematocrito, y se evaluaron las posibles correlaciones entre estos parámetros. El inóculo más bajo dio como resultado períodos de prepatencia más largos con respecto a los otros tres grupos. Además, se observó una moderada correlación negativa entre la duración del período prepatente y la rickettsemia. La sangre de cada uno de estos terneros se usó para la producción de vacunas comerciales. Se confirmó la respuesta humoral contra Anaplasma sp sesenta días post-vacunación mediante ELISA competitivo en un grupo representativo de bovinos inoculados con cada lote de vacuna producida. Por lo expuesto, concluimos que el inmunógeno obtenido mantuvo las características inmunoprofilácticas en todas las series de vacunas producidas. Además, esta descripción del modelo de infección experimental puede serútil para futuras investigaciones.Bovine anaplasmosis is an infectious transmissible disease caused by the rickettsia Anaplasmamarginale. Prophylaxis can be achieved by vaccination with A. centrale-infected erythrocytes (IE) obtained from splenectomized calves. Standardization of conditions for A. centrale infection of bovines can lead to a more efficient production system, which is particularly important when the vaccine is produced as a trivalent formulation that also contains erythrocytes infected with attenuated forms of Babesiabovis and B. bigemina parasites. In this study, bovines (n=26) were inoculated with different doses of A. centrale-infected erythrocytes (2, 3, 4 or 5 x 108 IE per animal). The course of infection was analyzed with regards to pre-patent period, rickettsemia, and maximal hematocrit decrease, and possible correlations between these parameters were evaluated. The lowest inoculum resulted in significantly lengthier pre-patent periods with respect to the other three groups. Also, a moderate negative correlation was observed between the length of the pre-patent period and rickettsemia. Blood from each of these calves was used to produce commercial vaccines. A humoral response against Anaplasma spat sixty days post vaccination was confirmed by competitive ELISA in a representative group of bovines inoculated with each batch of vaccine produced. Therefore, we conclude that the obtained immunogen maintained itsimmunoprophylactic characteristics in all the series produced. Also, this description of the experimental model could be useful for future investigations.Fil: Lozina, Laura Analía. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; Argentina. Litoral Biologicos SRL; ArgentinaFil: Rios, Elvio. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; ArgentinaFil: Barbieri, Antonela. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; ArgentinaFil: Bogado, Edgar Fabián. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; ArgentinaFil: Teibler, Gladys Pamela. Universidad Nacional del Nordeste. Facultad de Ciencias Veterinarias; ArgentinaFil: Jacobsen, Monica Ofelia. Instituto Nacional de Tecnologia Agropecuaria. Centro de Investigacion En Ciencias Veterinarias y Agronomicas. Instituto de Patobiologia Veterinaria. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Patobiologia Veterinaria.; Argentin

A novel type 1 cystatin involved in the regulation of Rhipicephalus microplus midgut cysteine proteases

Rhipicephalus microplus is a cattle ectoparasite found in tropical and subtropical regions around the world with great impact on livestock production. R. microplus can also harbor pathogens, such as Babesia sp. and Anaplasma sp. which further compromise cattle production. Blood meal acquisition and digestion are key steps for tick development. In ticks, digestion takes place inside midgut cells and is mediated by aspartic and cysteine peptidases and, therefore, regulated by their inhibitors. Cystatins are a family of cysteine peptidases inhibitors found in several organisms and have been associated in ticks with blood acquisition, blood digestion, modulation of host immune response and tick immunity. In this work, we characterized a novel R. microplus type 1 cystatin, named Rmcystatin-1b. The inhibitor transcripts were found to be highly expressed in the midgut of partially and fully engorged females and they appear to be modulated at different days post-detachment. Purified recombinant Rmcystatin-1b displayed inhibitory activity towards typical cysteine peptidases with high affinity. Moreover, rRmcystatin-1b was able to inhibit native R. microplus cysteine peptidases and RNAi-mediated knockdown of the cystatin transcripts resulted in increased proteolytic activity. Moreover, rRmcystatin-1b was able to interfere with B. bovis growth in vitro. Taken together our data strongly suggest that Rmcystatin-1b is a regulator of blood digestion in R. microplus midgut.Fil: Lu, Stephen. Universidade Federal de Sao Paulo; BrasilFil: da Rocha, Leticia A.. Universidade Federal de Sao Paulo; BrasilFil: Torquato, Ricardo J.S.. Universidade Federal de Sao Paulo; BrasilFil: da Silva Vaz Junior, Itabajara. Universidade Federal do Rio Grande do Sul; BrasilFil: Jacobsen, Monica Ofelia. Instituto Nacional de Tecnologia Agropecuaria. Centro de Investigacion En Ciencias Veterinarias y Agronomicas. Instituto de Patobiologia Veterinaria. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Patobiologia Veterinaria.; ArgentinaFil: Tanaka, Aparecida S.. Universidade Federal de Sao Paulo; Brasi

A new piroplasmid species infecting dogs: Morphological and molecular characterization and pathogeny of Babesia negevi n. sp.

Introduction: Babesiosis is a protozoan tick-borne infection associated with anemia and life-threatening disease in humans, domestic and wildlife animals. Dogs are infected by at least six well-characterized Babesia spp. that cause clinical disease. Infection with a piroplasmid species was detected by light microscopy of stained blood smears from five sick dogs from Israel and prompted an investigation on the parasite's identity. Methods: Genetic characterization of the piroplasmid was performed by PCR amplification of the 18S rRNA and the cytochrome c oxidase subunit 1 (cox1) genes, DNA sequencing and phylogenetic analysis. Four of the dogs were co-infected with Borrelia persica (Dschunkowsky, 1913), a relapsing fever spirochete transmitted by the argasid tick Ornithodoros tholozani Laboulbène & Mégnin. Co-infection of dogs with B. persica raised the possibility of transmission by O. tholozani and therefore, a piroplasmid PCR survey of ticks from this species was performed. Results: The infected dogs presented with fever (4/5), anemia, thrombocytopenia (4/5) and icterus (3/5). Comparison of the 18S rRNA and cox1 piroplasmid gene sequences revealed 99-100% identity between sequences amplified from different dogs and ticks. Phylogenetic trees demonstrated a previously undescribed species of Babesia belonging to the western group of Babesia (sensu lato) and closely related to the human pathogen Babesia duncani Conrad, Kjemtrup, Carreno, Thomford, Wainwright, Eberhard, Quick, Telfrom & Herwalt, 2006 while more moderately related to Babesia conradae Kjemtrup, Wainwright, Miller, Penzhorn & Carreno, 2006 which infects dogs. The piroplasm forms detected included tetrads (Maltese cross), merozoite and trophozoite stages whose average size was larger than stages of other canine Babesia spp. belonging to the Babesia (s.l.) and B. gibsoni Patton, 1910, and smaller than other canine Babesia (sensu stricto) spp. Of 212 O. tholozani ticks surveyed, 11 (5.2%) harbored DNA of the new species of Babesia. Conclusions: Babesia negevi n. sp. is described based on morphological and genetic characterization and phylogenetic analyses. The species is named after the Negev desert of southern Israel, where the first infected dog originated from. Despite co-infection in four dogs, the fifth dog had fatal disease attesting that B. negevi n. sp. infection requires clinical attention. Incriminating O. tholozani or another tick species as the vector of Babesia negevi n. sp., would require additional studies.Fil: Baneth, Gad. The Hebrew University of Jerusalem; IsraelFil: Nachum Biala, Yaarit. Koret School Of Veterinary Medicine; IsraelFil: Birkenheuer, Adam Joseph. North Carolina State University; Estados UnidosFil: Schreeg, Megan Elizabeth. North Carolina State University; Estados UnidosFil: Prince, Hagar. North Carolina State University; Estados UnidosFil: Jacobsen, Monica Ofelia. Instituto Nacional de Tecnologia Agropecuaria. Centro de Investigacion En Ciencias Veterinarias y Agronomicas. Instituto de Patobiologia Veterinaria. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Patobiologia Veterinaria.; ArgentinaFil: Schnittger, Leonhard. Instituto Nacional de Tecnologia Agropecuaria. Centro de Investigacion En Ciencias Veterinarias y Agronomicas. Instituto de Patobiologia Veterinaria. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Patobiologia Veterinaria.; ArgentinaFil: Aroch, Itamar. Koret School Of Veterinary Medicine; Israe

Validation and field evaluation of a competitive enzyme-linked immunosorbent assay for diagnosis of Babesia bovis infections in Argentina

Infections by Babesia bovis limit cattle production and cause important economic losses in tropical and subtropical areas around the world. Monitoring of calf sera can be used to detect unprotected cattle herds and to decide on strategic control measures, as well as for epidemiological studies. Merozoite surface antigen 2c (MSA-2c) is an immunodominant surface protein expressed in B. bovis merozoites and sporozoites and contains B-cell epitopes that are conserved among geographic isolates. A monoclonal antibody against recombinant MSA-2c (rMSA-2c) was previously shown to inhibit the binding of anti-B. bovis antibodies to a parasite B-cell epitope in a competitive enzyme-linked immunosorbent assay (cELISA) format. In the work at hand, the parameters of this cELISA were reevaluated and adjusted when necessary, and a cutoff value was determined by receiver operator characteristic (ROC) curve analysis of a total of 357 bovine sera of known reactivity, as assessed by indirect immunofluorescence assay (IFAT). The established rMSA-2c cELISA demonstrated a specificity of 98% and a sensitivity of 96.2%. An additional set of 303 field bovine sera from regions where ticks are endemic and tick-free regions of Argentina was tested by both rMSA-2c cELISA and IFAT, and the results were shown to be in very good agreement (kappa index, 0.8325). The performance shown by rMSA-2c cELISA in the detection of B. bovis-specific antibodies and its suitability for standardization and large-scale production, as well as the possibility of its application in most veterinary diagnostic laboratories, make the assay a powerful tool for the surveillance of herd immunity as a strategic measure for the control of bovine babesiosis.Fil: Dominguez, Mariana Gabriela. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Patobiología; ArgentinaFil: Echaide, Ignacio Eduardo. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; ArgentinaFil: Torioni de Echaide, Susana Marta. Instituto Nacional de Tecnología Agropecuaria. Centro Regional Santa Fe. Estación Experimental Agropecuaria Rafaela; ArgentinaFil: Wilkowsky, Silvina Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Biotecnología; ArgentinaFil: Zabal, Osvaldo Alfredo. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Virología; ArgentinaFil: Mosqueda, Juan J.. Universidad Autonoma de Queretaro.; MéxicoFil: Schnittger, Leonhard. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Patobiología; ArgentinaFil: Jacobsen, Monica Ofelia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Patobiología; Argentin

A novel neutralization sensitive and subdominant RAP-1-related antigen (RRA) is expressed by Babesia bovis merozoites

Objective. The Babesia bovis genome encodes a rap-1 related gene denominated RAP-1 related antigen (RRA). In this study, we analysed the pattern of expression, immunogenicity and functional relevance of RRA. Methods. Phylogenetic analysis was performed using the program Phylip. Expression of rra was analysed by Northern blots, RT-PCR, immunoprecipitation, Western blots and immunofluorescence. RRA antigenicity was tested by T-cell proliferation and Western blot analysis, and functional relevance was determined in an in vitro neutralization assay. Results. RRA is more closely related to RAP-1b of Babesia bigemina than to B. bovis RAP-1, and it is highly conserved among distinct strains. Transcriptional analysis suggests lower numbers of rra transcripts compared to rap-1. Immunoprecipitation of metabolically labelled B. bovis proteins with antibodies against synthetic peptides representing predicted antigenic regions of RRA confirmed the expression of a ∼43 kDa RRA in cultured merozoites. Antibodies present in B. bovis hyperimmune sera, but not in field-infected cattle sera, reacted weakly with recombinant RRA, and no significant stimulation was obtained using recombinant RRA as antigen in T-cell proliferation assays, indicating that RRA is a subdominant antigen. Antibodies against RRA synthetic peptides reacted with merozoites using immunofluorescence, and were able to significantly inhibit erythrocyte invasion in in vitro neutralization tests, suggesting functional relevance for parasite survival. Conclusion. B. bovis express a novel subdominant RAP-1-like molecule that may contribute to erythrocyte invasion and/or egression by the parasite.Fil: Suarez, Carlos E.. United States Department of Agriculture. Agriculture Research Service; Estados Unidos. Washington State University; Estados UnidosFil: Laughery, Jacob M.. Washington State University; Estados UnidosFil: Bastos, Reginaldo G.. Washington State University; Estados UnidosFil: Johnson, Wendell C.. United States Department of Agriculture. Agriculture Research Service; Estados UnidosFil: Norimine, Junzo. Washington State University; Estados UnidosFil: Asenzo, Gustavo Daniel. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas; ArgentinaFil: Brown, Wendy C.. Washington State University; Estados UnidosFil: Jacobsen, Monica Ofelia. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas; ArgentinaFil: Goff, Will L.. United States Department of Agriculture. Agriculture Research Service; Estados Unido

Introduction into Parasitic Protozoa

Parasitic protozoans are protists—i.e., unicellular eukaryotes. Besides, they share the common features of being heterotrophic, motile in at least one of their stages, and dependent on a host for survival. Protists are a highly diverse evolutionary unrelated grouping that is at present taxonomically divided into at least five supergroups or eukaryotic kingdoms: SAR, Excavata, Amoebozoa, Archaeplastida, and Ophistokonta. The protozoan parasites that infect farm animals and pets, and are the subject of this book, belong to the first three supergroups. These organisms can cause significant morbidity and mortality in domestic animals, thus provoking substantial economic losses associated with livestock production or major concern for pet owners. Additionally, some are zoonotic and of public health relevance. Human domestication has led to a huge world population of a few selected farm and pet animals, usually raised in close proximity. This has provided an ideal and spacious ecological niche for parasitic protozoans that invade and thrive in these hosts. In addition, international travel has promoted global distribution of most parasitic protozoa. A long history of coadaptation has existed between parasites and their wild ancestor hosts, whereas adaptation to domestic animals has been much shorter from an evolutionary perspective. While the first scenario resulted in unapparent infections that ensured parasite perpetuation, the second represents an unbalanced situation resulting in clinical signs and mortality. This calls for continuous efforts in the development and application of control measures.Fil: Schnittger, Leonhard. Instituto Nacional de Tecnologia Agropecuaria. Centro de Investigacion En Ciencias Veterinarias y Agronomicas. Instituto de Patobiologia Veterinaria. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Patobiologia Veterinaria.; Argentina. Universidad de Morón; ArgentinaFil: Jacobsen, Monica Ofelia. Instituto Nacional de Tecnologia Agropecuaria. Centro de Investigacion En Ciencias Veterinarias y Agronomicas. Instituto de Patobiologia Veterinaria. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Patobiologia Veterinaria.; Argentina. Universidad de Morón; Argentin

Rhipicephalus microplus ticks can complete their life cycle on the water buffalo (Bubalus bubalis)

Rhipicephalus (Boophilus) microplus is considered one of the most important ectoparasites ofcattle worldwide. Due to the increase in the number of water buffaloes (Bubalus bubalis) in R. microplus-infested areas, this studywas designed to determine whether these ruminants are able to sustain the complete tick life cycle. To this aim, a seven-month old water buffalo of the Mediterranean breed and a Holstein bovine of the same age, both tick-naïve, were infested with R. microplus tick larvae, and the parasitic and non-parasitic tick stages were analyzed and compared. The studied parameters include the number of recovered engorged females, the time points at which the first and last engorged females fell to the ground; the pre-oviposition duration, the percentage of hatching and the reproductive efficiency index. No statistically significant differences were found between the buffalo and the bovine in all parameters measured. It was concluded that the water buffalo can act as a suitablereservoir for R. microplus ticks. These results should be taken into account when implementing tick control and eradication campaignsin water buffalo grazing lands.Fil: Benitez, Daniel Francisco. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Corrientes. Estacion Experimental Agropecuaria Mercedes. Agencia de Extension Rural Mercedes.; ArgentinaFil: Cetrá, Bibiana. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Corrientes. Estacion Experimental Agropecuaria Mercedes. Agencia de Extension Rural Mercedes.; ArgentinaFil: Jacobsen, Monica Ofelia. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Patobiología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Sarcocystis

Sarcocystis (derived from the Greek words sarx, which means flesh, and kystis,which means bladder) are apicomplexan protozoans that cause sarcocystosis orsarcocystiosis. Infections are characterized by the formation of numerous sarcocysts, which are essentially parasite-full sacs ranging in size from micrometers to several centimeters, in the muscles or nervous tissue of a great variety of animals. The genus is composed of more than 100 species that differ in pathogenicity, host specificity, and sarcocyst structure and location. Sarcocystis are obligatory intracellular, with a typical coccidian life cycle, consisting of merogony, gametogony, and sporogony. The life cycle involves an intermediate and a definitive host, usually an herbivore and a carnivore, respectively. At first, a series of asexual reproduction steps culminate with sarcocyst formation. Ingestion of cyst-infected tissues by the definitive host leads to sexual reproduction of the parasite in the digestive tract, followed by excretion of infective forms in the feces. The cycle is closed when an intermediate host becomes infected by the fecal-oral route. Most Sarcocystis are species-specific for intermediate and family-specific for definitive hosts. Infection of farm animals is sometimes associated with the reduction in quality and quantity of meat, wool, and fiber, resulting in important economic losses. Additionally, some Sarcocystis species are zoonotic. Thus, the study of sarcocystosis constitutes an active field of research.Fil: Decker Franco, Cecilia. Instituto Nacional de Tecnologia Agropecuaria. Centro de Investigacion En Ciencias Veterinarias y Agronomicas. Instituto de Patobiologia Veterinaria. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Patobiologia Veterinaria.; ArgentinaFil: Schnittger, Leonhard. Instituto Nacional de Tecnologia Agropecuaria. Centro de Investigacion En Ciencias Veterinarias y Agronomicas. Instituto de Patobiologia Veterinaria. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Patobiologia Veterinaria.; ArgentinaFil: Jacobsen, Monica Ofelia. Instituto Nacional de Tecnologia Agropecuaria. Centro de Investigacion En Ciencias Veterinarias y Agronomicas. Instituto de Patobiologia Veterinaria. - Consejo Nacional de Investigaciones Cientificas y Tecnicas. Oficina de Coordinacion Administrativa Pque. Centenario. Instituto de Patobiologia Veterinaria.; Argentin

Rhipicephalus microplus ticks can complete their life cycle on the water buffalo (Bubalus bubalis)

Rhipicephalus (Boophilus) microplus is considered one of the most important ectoparasites ofcattle worldwide. Due to the increase in the number of water buffaloes (Bubalus bubalis) in R. microplus-infested areas, this studywas designed to determine whether these ruminants are able to sustain the complete tick life cycle. To this aim, a seven-month old water buffalo of the Mediterranean breed and a Holstein bovine of the same age, both tick-naïve, were infested with R. microplus tick larvae, and the parasitic and non-parasitic tick stages were analyzed and compared. The studied parameters include the number of recovered engorged females, the time points at which the first and last engorged females fell to the ground; the pre-oviposition duration, the percentage of hatching and the reproductive efficiency index. No statistically significant differences were found between the buffalo and the bovine in all parameters measured. It was concluded that the water buffalo can act as a suitablereservoir for R. microplus ticks. These results should be taken into account when implementing tick control and eradication campaignsin water buffalo grazing lands.Fil: Benitez, Daniel Francisco. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Corrientes. Estacion Experimental Agropecuaria Mercedes. Agencia de Extension Rural Mercedes.; ArgentinaFil: Cetrá, Bibiana. Instituto Nacional de Tecnologia Agropecuaria. Centro Regional Corrientes. Estacion Experimental Agropecuaria Mercedes. Agencia de Extension Rural Mercedes.; ArgentinaFil: Jacobsen, Monica Ofelia. Instituto Nacional de Tecnología Agropecuaria. Centro de Investigación en Ciencias Veterinarias y Agronómicas. Instituto de Patobiología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin