Frequency of antibodies class IgG anti-Rickettsia rickettsii in horses of Universidade Federal Rural do Rio de Janeiro, Seropédica campus

ABSTRACT. Cordeiro M.D., Raia V.A., Valim J.R.A., Castro G.N.S., Souza C.E. & Fonseca A.H. [Frequency of antibodies class IgG anti-Rickettsia rickettsii in horses of Universidade Federal Rural do Rio de Janeiro, Seropédica campus.] Frequência de anticorpos da classe IgG anti-Rickettsia rickettsii em equinos na Universidade Federal Rural do Rio de Janeiro, Campus Seropédica. Revista Brasileira de Medicina Veterinária, 37(1):78-82, 2015. Departamento de Epidemiologia e Saúde Pública, Instituto de Veterinária, Universidade Federal Rural do Rio de Janeiro, Campus Seropédica, BR 465, Km7, Seropédica, RJ 23890-000, Brasil. E-mail: [email protected] The aim of this study was to verify, through the indirect immunofluorescence assay (IFA), the frequency of anti-Rickettsia rickettsii antibodies in horses at Universidade Federal Rural do Rio de Janeiro (UFRRJ) Seropédica campus, state of Rio de Janeiro. We analyzed serum samples from 42 horses from Department of Breeding Equine of UFRRJ. All samples were tested using fixed slides with antigens for R. rickettsii, Rickettsia rhipicephali and Rickettsia parkeri. We observed an overall prevalence of Rickettsia spp. 83.33% (35/42). For the agent R. rickettsii revealed a prevalence of 66.67% (28/42), still being categorized in titers of 1:64 (19/28) and 1:128 (9/28). Nine of the 28 positives horses for R. rickettsii (21.43%) were no reactive to other agents, with titers 1:64 (8/9) and 1:128 (1/9). The only tick species found parasitizing horses on the campus of UFRRJ during the collection period were Amblyomma cajennense and Dermacentor nitens. The UFRRJ presents an environment that provides a ideal epidemiological niche for the permanence of Rickettsia bacteria. The high prevalence found in this study indicates that attention to epidemiological agent of Brazilian Spotted Fever in the study area is of utmost importance. The aim of this study was to verify, through the indirect immunofluorescence assay (IFA), the frequency of anti-R. rickettsii antibodies in horses at Universidade Federal Rural do Rio de Janeiro (UFRRJ) Seropédica campus, state of Rio de Janeiro. We analyzed serum samples from 42 horses Department Breeding Equine of UFRRJ. All samples were tested using fixed slides with antigens for R. rickettsii, Rickettsia rhipicephali and Rickettsia parkeri. We observed an overall prevalence of Rickettsia spp. 83.33% (35/42). For the agent R. rickettsii revealed a prevalence of 66.67% (28/42), still being categorized in titers of 1:64 (19/28) and 1:128 (9/28). Nine of the 28 positives horses for R. rickettsii (21.43%) were no reactive to other agents, with titers 1:64 (8/9) and 1:128 (1/9). The only tick species found parasitizing horses on the campus of UFRRJ during the collection period were Amblyomma cajennense and Dermacentor nitens. The UFRRJ presents an environment that provides an ideal epidemiological niche for the circulation of rickettsia bacteria. The high prevalence found in this study indicates a probable circulation of Rickettsia spp., having thus risk for human infection in the study are

Transovarial transmission and finding of Trypanosoma rhipicephalis in the hemolymph of Rhipicephalus sanguineus sensu lato

Trypanosoma rhipicephalis Marotta et al. (2018) is a species isolated from Rhipicephalus microplus ticks collected from native bovine Seropédica, in the state of Rio de Janeiro. This study aimed to investigate the interaction of the tick Rhipicephalus sanguineus s. l. with T. rhipicephalis by in vitro artificial feeding. Eight females of R. sanguineus s. l. partially fed on rabbits. Tick infection was performed by an artificial feeding system using plastic tips for 12 hours. Canine blood used for feeding the ticks test group was previously infected with T. rhipicephalis 108/mL. The hemolymph smear test was performed in all females after experimental infection. The daily posture was collected and organized in pools of each female per posture day. The eggs were divided into three groups, the first group for eggs PCR, the second for hatching and larval PCR, and the third group of eggs for isolation in cell culture. The evaluation of the presence of DNA in the macerated eggs of experimentally infected ticks showed two positive PCR samples. The evaluation of the presence of DNA in experimentally infected females showed all samples tested positive. For the hemolymph test, tick number 7 presented epimastigote developmental forms and amastigotes of T. rhipicephalis. Experimental infection by artificial feeding proved to be a suitable tool to study the interaction of T. rhipicephalis in R. sanguineus s. l. ticks. The results show the transovarial transmission of T. rhipicephalis by R. sanguineus s. l., as well as the interaction of the protozoan in the organism of this tick species

Detecção sorológica de Anaplasma marginale, Babesia bovis E Babesia bigemina em bovinos de corte das regiões Norte e Centro Oeste do Brasil

The objective of this study was to assess the occurrence of antibodies against Anaplasma marginale, Babesia bovis and Babesia bigemina in beef cattle of the northern and central-western regions of Brazil. A total of 1703 blood samples were collected from cattle from 100 farms distributed among 37 municipalities in the states of Mato Grosso, Pará and Tocantins. The search for antibodies was conducted using an indirect enzyme-linked immunosorbent assay (ELISA), and antibodies were observed for B. bovis, B. bigemina and A. marginale in cattle from Mato Grosso, Tocantins and Pará at rates of 99%, 90% and 41%; 99%, 70% and 52%; and 97%, 97% and 75%, respectively. The results show that the analyzed regions exhibit enzootic stability for infection with B. bovis and B. bigemina, whereas the same result was not observed with A. marginale.O objetivo deste estudo foi verificar a ocorrência de anticorpos contra Anaplasma marginale, Babesia bovis e Babesia bigemina em bovinos de corte das regiões Norte e Centro Oeste do Brasil. Foram selecionadas randomicamente 1703 amostras de sangue de bovinos em 100 propriedades rurais distribuídos em 37 municípios dos estados do Mato Grosso, Pará e Tocantins. A pesquisa de anticorpos foi realizada por meio do Ensaio de Imunoadsorção Enzimático (ELISA) Indireto. A ocorrência de anticorpos observada para B. bovis, B. bigemina e A. marginale em bovinos dos estados do Mato Grosso, Tocantins e Pará foi 99%, 90% e 41%; 99%, 70% e 52% e 97%, 97% e 75%, respectivamente. Os resultados mostram que as regiões analisadas apresentam estabilidade enzoótica para a infecção por B. bovis e B. bigemina, não sendo observado o mesmo para Anaplasma marginale

Use of plastic tips in artificial feeding of Dermacentor (Anocentor) nitens females Neumann, 1897 (Acari: Ixodidae)

The establishment of laboratory colonies of ticks is often hampered by their lack of adaptation to alternative hosts. The aim of this study was to artificially feed partially engorged Dermacentor (Anocentor) nitens females through plastic tips, and to identify what are the optimal conditions of application of this technique to get as much as possible close to the natural conditions. The technique of artificial feeding through plastic tips allowed the engorgement of D. nitens ticks to a final weight within the normal range for the species. (C) 2014 Published by Elsevier GmbH

Effects of fluazuron on the biological parameters of engorged females of Rhipicephalus microplus

The objective of this study was to evaluate the biological parameters of Rhipicephalus microplus engorged females exposed to the arthropod growth regulator fluazuron. A commercial formulation based on fluazuron (Acatak®, Novartis) was administered topically to stabled cattle artificially infested with R. microplus larvae. The infestations occurred on four alternate days (days -21, -17, -13 and -6) taking as day 0 (zero) the day of treatment with a single dose of fluazuron for the treated group. Fifteen engorged females from each group were collected from the floor of the stalls at the end of the engorgement period (21 days) on pre-established days: before (day 0) and after treatment (days 4, 8 and 15), respectively. After cleaning and preparation of the engorged females in the laboratory, the following biological parameters were analyzed: weight of the engorged female, weight of the female after laying (spent female), laying period, weight of the posture, egg production index, reproductive efficiency index, hatching percentage, and nutritional index. The average weight of engorged females showed a significant reduction on all days after treatment in the exposed group. Aside from the weight after laying, all other biological parameters showed a significant reduction on the eighth post-treatment day due to exposure to fluazuron. Knowledge of the effects of an active principle on biological parameters in a population of ticks is essential for appropriate implementation of integrated management practices for parasite control

Using plastic tips in artificial feeding of Rhipicephalus sanguineus sensu lato (Acari: Ixodidae) females

Abstract This study evaluated the influence of the initial weight, feeding period and temperature on weight gain and biological parameters of the non-parasitic phase of partially engorged Rhipicephalus sanguineus females that were artificially fed using plastic tips as feeding devices. The device did not alter the oviposition of the females or any other parameters evaluated. Furthermore, it was observed that the temperature of the feeding the group did not affect the weight gain and biology of ticks. This device has great potential for the development of studies on bioagent transmission because it provides higher intake of blood by ixodid ticks