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Anaplasmosis is a worldwide hemolytic disease in cattle caused by a gram-negative obligatory intracellular bacterium, characterized by anemia and jaundice. Among the treatments used for anaplasmosis is a drug called imidocarb dipropionate, also indicated as an immunomodulator agent. However, it causes side effects associated with increased levels of acetylcholine. In view of this, the effects of imidocarb dipropionate on the purinergic system, and antioxidant enzymes in animals naturally infected by Anaplasma marginale were evaluated. Young cattle (n = 22) infected by A. marginale were divided into two groups: the Group A consisted of 11 animals used as controls; and the Group B composed of 11 animals. Imidocarb dipropionate (5 mg/kg) was used subcutaneously to treat both groups (the Group A on day 6 and the Group B on day 0). The treatment reduced acetylcholinesterase (AChE), and adenosine deaminase (ADA) activities, and increased the dismutase superoxide and catalase activities. No changes on lipid peroxidation (TBARS levels) and BChE activities were noticed. These results suggest that imidocarb dipropionate used to treat A. marginale infection in cattle has effect on antioxidant enzymes, and significantly inhibits the enzymatic activities of ADA and AChE., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

The objective of this study was to assess the influence of an asymptomatic experimental infection by Babesia bigemina on cholinesterase's as markers of the inflammatory process and biomarkers of oxidative imbalance. For this purpose, eight naive animals were used, as follows: four as controls or uninfected; and four infected with an attenuated strain of B. bigemina. Blood samples were collected on days 0, 7 and 11 post-inoculation (PI). Parasitemia was determined by blood smear evaluation, showing that the infection by B. bigemina resulted in mean 0.725 and 0.025% on day 7 and 11 PI, respectively, as well as mild anemia. The activities of acetylcholinesterase, butyrylcholinesterase and catalase were lower, while levels of thiobarbituric acid reactive substances and superoxide dismutase activity were higher in infected animals, when compared with the control group. This attenuated strain of B. bigemina induced an oxidative stress condition, as well as it reduces the cholinesterasés activity in infected and asymptomatic cattle. Therefore, this decrease of cholinesterase in infection by B. bigemina purpose is to inhibit inflammation, for thereby increasing acetylcholine levels, potent anti-inflammatory molecules., (Copyright © 2016. Published by Elsevier Ltd.)

The tick Rhipicephalus (Boophilus) microplus is a blood-sucking ectoparasite of cattle that severely impairs livestock production. Studies on tick immunological control address mostly single-antigen vaccines. However, from the commercial standpoint, so far no single-antigen vaccine has afforded appropriate protection against all R. microplus populations. In this context, multi-antigen cocktails have emerged as a way to enhance vaccine efficacy. In this work, a multi-antigenic vaccine against R. microplus was analyzed under field conditions in naturally infested cattle. The vaccine was composed by three tick recombinant proteins from two tick species that in previous single-vaccination reports provided partial protection of confined cattle against R. microplus infestations: vitellin-degrading cysteine endopeptidase (VTDCE) and boophilus yolk pro-cathepsin (BYC) from R. microplus, and glutathione S-transferase from Haemaphysalis longicornis (GST-Hl). Increased antibody levels against three proteins were recorded after immunizations, with a distinct humoral immune response dynamics for each protein. Compared to the control group, a statistically significant lower number of semi-engorged female ticks were observed in vaccinated cattle after two inoculations. This reduction persisted for 3 months, ranging from 35.3 to 61.6%. Furthermore, cattle body weight gain was significantly higher in vaccinated animals when compared to control cattle. Compared to the single-antigen vaccines composed by VTDCE, BYC or GST-Hl, this three-antigen vaccine afforded higher protection levels against R. microplus infestations., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

Anaplasmosis, a persistent intraerythrocytic infection of cattle by Anaplasma marginale, causes severe anemia and a higher rate of abortion, resulting in significant loss to both dairy and beef industries. Clinical diagnosis is based on symptoms and confirmatory laboratory tests are required. Currently, all the diagnostic assays have been developed with whole antigens with indirect ELISA based on multiple epitopes. In a pioneer investigation we demonstrated the use of critical motifs of an epitope as biomarkers for immunosensor applications. Mimotopes of the MSP1a protein functional epitope were obtained through Phage Display after three cycles of selection of a 12-mer random peptide library against the neutralizing monoclonal antibody 15D2. Thirty-nine clones were randomly selected, sequenced, translated and aligned with the native sequence. The consensus sequence SxSSQSEASTSSQLGA was obtained, which is located in C-terminal end of the 28-aa repetitive motif of the MSP1a protein, but the alignment and sequences' variation among mimotopes allowed us to map the critical motif STSSxL within the consensus sequence. Based on these results, two peptides were chemically synthesized: one based on the critical motif (STSSQL, Am1) and the other based on the consensus sequence aligned with the native epitope (SEASTSSQLGA, Am2). Sera from 24 infected and 52 healthy animals were tested by ELISA for reactivity against Am1 and Am2, which presented sensitivities of 96% and 100%, respectively. The Am1 peptide was incorporated onto a biolectrode (graphite modified with poly-3-hydroxyphenylacetic acid) and direct serum detection was demonstrated by impedance, differential pulse voltammetry, and atomic force microscopy. The electrochemical sensor system proved to be highly effective in discriminating sera from positive and negative animals. These immunosensors were highly sensitive and selective for positive IgG, contaminants did not affect measurements, and were based on a simple, fast and reproducible electrochemical system. [ABSTRACT FROM AUTHOR]