scholarly journals Assessing HeberFast® Line Gavac, a lateral flow immunochromatographic system for the rapid detection of anti-Bm86 antibodies in Gavac vaccinated cattle

Bionatura ◽  
2021 ◽  
Vol 3 (3) ◽  
pp. 1902-1908
Author(s):  
Milagros Vargas-Hernández ◽  
Yeni Hernández Lorenzo Hernández Lorenzo ◽  
Viviana Pluma Perez ◽  
Isabel Rosales-Garcia Rosales-Garcia ◽  
Sunamit Rodríguez-Mendez ◽  
...  

Rhipicephalus Boophilus microplus cattle tick is a scourge for livestock production. The infestations produced by this pathogen are incompletely contained by chemical treatments, with the associated environmental pollution risks. Vaccination against cattle ticks has emerged as a feasible and environmentally friendly strategy to control tick-borne diseases. In this setting, Gavac® vaccine has proven effective in decreasing cattle tick populations through antibody responses against the tick Bm86 antigen, as part of an Integrated Control Program. However, animal vaccination programs require easy and ready-to-use screening tests to follow up the immune response in vaccinated animals under field conditions. This study reports the evaluation HeberFast® Line Gavac, a lateral flow immunochromatographic system for the rapid detection of anti Bm86 antibodies in vaccinated cattle. The system was tested on 598 serum samples taken from immunized animals, arranged in three groups according to their anti-Bm86 antibody response in ELISA (209 high, 150 medium or 239 low and 100 samples from non-immunized animals. The HeberFast® Line Gavac system was assessed for sensitivity, specificity, and concordance against the ELISA reference test. Consistency was evaluated among production batches and inter-analyst reading-independent consistency at two moments: ten minutes after completing the test and after strip drying. The system showed high sensitivity (81.6%, 82.2%, and 81%), specificity (96.7, 94.6, and 93.3%), and agreement with the ELISA reference test (75%; 74%, and 71%) for high, medium and low anti-Bm86 sera, respectively. The effectiveness of the diagnosis was 87.6; 87.1; 85.9 for high, medium, and low antibody titers, respectively. Consistency among production batches and analysts was documented, and no significant differences between evaluation times were found. These results indicate that HeberFast® Line Gavac is a valuable tool for the serological surveillance of Gavac vaccinated cattle.

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Marina Popara ◽  
Margarita Villar ◽  
Lourdes Mateos-Hernández ◽  
Isabel G. Fernández de Mera ◽  
José de la Fuente

Cattle ticks,Rhipicephalus (Boophilus) microplus, are a serious threat to animal health and production. Some ticks feed on a single host species while others such asR. microplusinfest multiple hosts. White tailed deer (WTD) play a role in the maintenance and expansion of cattle tick populations. However, cattle ticks fed on WTD show lower weight and reproductive performance when compared to ticks fed on cattle, suggesting the existence of host factors that affect tick feeding and reproduction. To elucidate these factors, a proteomics approach was used to characterize tick and host proteins inR. microplusticks fed on cattle and WTD. The results showed thatR. microplusticks fed on cattle have overrepresented tick proteins involved in blood digestion and reproduction when compared to ticks fed on WTD, while host proteins were differentially represented in ticks fed on cattle or WTD. Although a direct connection cannot be made between differentially represented tick and host proteins, these results suggested that differentially represented host proteins together with other host factors could be associated with higherR. microplustick feeding and reproduction observed in ticks fed on cattle.


2018 ◽  
Vol 84 (0) ◽  
Author(s):  
Eduardo Oliveira ◽  
Manoela da Silva ◽  
Lew Sprenger ◽  
Daniela Pedrassani

ABSTRACT: Rhipicephalus (Boophilus) microplus, known as the cattle tick, is a cause of great economic losses for dairy cattle farming because of its high frequency of occurrence and the difficulty in controlling it. The aim of this study was to evaluate the in vitro activity of Chenopodium ambrosioides extract on R. (B.) microplus. For this purpose, 125 females were selected and classified into five groups according to their weight, in order to ensure that the females used presented homogeneous weight. The treatments comprised 40 and 60% extracts of Chenopodium ambrosioides, distilled water, ethanol (70ºGL) and 12.5% amitraz. The extracts of C. ambrosioides (40 and 60%) showed effectiveness of 99.7 and 100% and higher percentages of dead females than the other treatments: 64 and 96%, respectively (p<0.001). In the groups exposed to distilled water and ethanol (70º GL), 92 and 88% of the females maintained oviposition. In the females exposed to 40 and 60% extracts, oviposition of 36 and 4% occurred, respectively. It was concluded that the extract of Chenopodium ambrosioides, at both concentration evaluated, had high efficiency against engorged females of cattle ticks.


2012 ◽  
Vol 21 (1) ◽  
pp. 22-27 ◽  
Author(s):  
Maria Alice Zacarias do Amaral ◽  
Márcia Cristina de Azevedo Prata ◽  
Erik Daemon ◽  
John Furlong

With the objective of encouraging the use of rabbits as alternative hosts for the cattle tick, four rabbits were infested on the ears and back. From the second day of infestation the developmental stages were observed. e duration of larval engorgement and changes were estimated between six and eight days in the region of the back and between 've and seven days in the pinna. e nymphal engorgement and changes occurred at approximately 10.80 ± 2.65 days in the dorsal and 11.00 ± 2.52 days in the ear, with the engorgement of adults and copulation occurring at 7.03 ± 2.45 days, on the dorsal region and 8.55 ± 1.82 days in the region of the pinna. e parasitic period ranged from 21 to 29 days (back) and from 23 to 30 days (pinna). e engorged females of the back and ear weighed on average 34.43 ± 18.73 and 36.30 ± 18.10 mg, respectively. e nutritional and reproductive e/ciency indexes were 17.38 ± 14.27 and 26.85 ± 17.13% (back) and 17.42 ± 12.22% and 30.70 ± 19.80% (pinna). Although not appropriate to maintain successive generations of Rhipicephalus (Boophilus) microplus, rabbits can be used for di:erent stages of engorgement of the ixodid, allowing experimental studies.


2011 ◽  
Vol 20 (2) ◽  
pp. 103-110 ◽  
Author(s):  
Rodrigo Casquero Cunha ◽  
Renato Andreotti ◽  
Fábio Pereira Leivas Leite

The cattle tick Rhipicephalus (Boophilus) microplus is responsible for great economic losses. It is mainly controlled chemically, with limitations regarding development of resistance to the chemicals. Vaccines may help control this parasite, thereby reducing tick pesticide use. In this light, we performed subcloning of the gene of the protein Bm86-GC, the homologue protein that currently forms the basis of vaccines (GavacTM and TickGardPLUS) that have been developed against cattle ticks. The subcloning was done in the pPIC9 expression vector, for transformation in the yeast Pichia pastoris. This protein was characterized by expression of the recombinant Mut+ strain, which expressed greater quantities of protein. The expressed protein (rBm86-CG) was recognized in the Western-blot assay using anti-Gavac, anti-TickGard, anti-larval extract and anti-rBm86-CG polyclonal sera. The serum produced in cattle vaccinated with the antigen CG rBm86 presented high antibody titers and recognized the native protein. The rBm86-GC has potential relevance as an immunogen for vaccine formulation against cattle ticks.


1953 ◽  
Vol 1 (3) ◽  
pp. 345 ◽  
Author(s):  
PR Wilkinson

In larval cattle ticks the main sense organs which have been recognized are the eyes, Haller's organs, and the palpal organs; the four pairs of sensilla sagittiformia may also have a sensory function. Larvae were allowed to ascend supports simulating grass stalks and were tested for response to vibration, air currents, interrupted illumination, warm and moist objects, and odours from skin secretions of man and cattle. The strongest questing response was to the odours. Larvae which had been exposed to low humidities collected around and imbibed from drops of water. The main stimulus governing ascent of the grass blades appeared to be positive phototaxis to moderate light intensities. Larvae sheltered from direct sunlight. Larvae in the field were found to be more exposed in the early morning, often being at the tops of grass stalks. Measurements of light, air temperature, and humidity indicated that light intensity might govern this movement. This suggests that larval sampling in the pasture should take place in the first half of the morning. In a single series of observations, larvae which had hatched at the base of straws were observed to ascend them in the late afternoon. In a few experiments isolated larvae ascended artificial supports above the reach of a bovine host but groups were always found at heights within reach.


1988 ◽  
Vol 28 (4) ◽  
pp. 473 ◽  
Author(s):  
RW Sutherst ◽  
LJ Wilson ◽  
R Reid ◽  
JD Kerr

Stylosanthes viscosa and S. scabra cvv. Fitzroy and Seca have previously been shown to trap host-seeking larvae of the cattle tick Boophilus microplus and could provide a means of controlling cattle ticks in improved pastures. We assessed the ability of 229 accessions from 22 species of the genus Stylosanthes to trap larvae of B. microplus or to prevent them from ascending plant stems. The 3 species that were most effective were S. viscosa, S. scabra and S. guianensis. Only accessions which produced sticky secretions were able to trap tick larvae, but the extent of this ability was related primarily to the density and length of bristles on the stems rather than to the degree of stickiness. The highest percentages of larvae were trapped when stylo stems had short, dense bristles of average stickiness or long sticky bristles of average density. These features were also most effective at preventing larvae from ascending stems. A high density of fine, non-glandular hairs, in conjunction with average stickiness, also prevented larvae from ascending stems.


1959 ◽  
Vol 10 (1) ◽  
pp. 129 ◽  
Author(s):  
PR Wilkinson ◽  
JT Wilson

Observations on the gradual distension and shrinkage of cattle tick larvae (Boophilus microplus (Canestrini)) confirmed that they can take up water from, or lose water to, the atmosphere under suitable conditions. Further evidence was obtained that partially desiccated larvae can drink when in contact with free water. Consideration of the relative humidities recorded over sward adjoining a creek, during a drought, suggested that larvae would be able to absorb moisture during the 9-hr period before dawn. Dew m-as also available to the larvae in drought time, and on most mornings when observations were made. In the laboratory, larvae in cultures supplied with water droplets lived longer than those in similar cultures not supplied with water. Larval clusters on artificial supports out of doors lived longer if protected by fabric shades. At intervals over 2 years, female ticks were placed in grassland near Rockhampton and at Yeppoon, Qld., under simulated natural conditions. The times of hatching and periods of survival of the larvae were observed. In contrast with the marked decrease in tick fertility which occurs in the winter in south Queensland, ticks put out throughout the winter at Rockhampton laid large numbers of fertile eggs. Very few larval progeny of ticks put out in summer survived 3 months after the date of placement of the parent female. Progeny of ticks put out in the winter persisted up to 54 months after the date of placement of the parent. A graph of the 'pre-hatch' (pre-oviposition plus developmental) periods against screen temperatures followed the trend expected from laboratory data, but the difference between actual and computed hatching dates was large in some cases. Actual hatching date was usually later than computed hatching date, both for ticks in the soil and for ticks in humidified containers in a meteorological screen. The comparatively short survival periods of larvae in the central Queensland summer indicated the practicability of controlling the cattle tick by temporarily destocking pastures.


2013 ◽  
Vol 22 (3) ◽  
pp. 379-384 ◽  
Author(s):  
Márcia Cristina Mendes ◽  
Fernanda Calvo Duarte ◽  
João Ricardo Martins ◽  
Guilherme Marcondes Klafke ◽  
Leonardo Costa Fiorini ◽  
...  

Cattle ticks Rhipicephalus(Boophilus) microplus are mainly controlled in Brazil by means of acaricide products, without any official policies in this regard. Acaricides continue to be sold indiscriminately, and this has contributed towards making the problem of resistance widespread, thus making diagnosis and monitoring of tick resistance essential. Here, bioassays (larval packet test) were performed on tick populations from the states of Rio Grande do Sul and Mato Grosso do Sul regarding their susceptibility to cypermethrin, deltamethrin and flumethrin. All the tick samples tested showed resistance to cypermethrin (10) (resistance factor (RF) ranging from 5.6 to 80.3) and deltamethrin (10) (RF ranging from 2.4 to 83.1). Six out of eight populations were resistant to flumethrin (RF ranging from 3.8 to 8.2). PCR molecular analyses did not show any T2134A mutations in the voltage-gated sodium channel gene, in any of the sampled populations. The results from this study highlight the critical status of resistance of the cattle tick to synthetic pyrethroids in the regions studied. Further studies are needed to identify the mechanisms responsible for the resistant phenotypes observed in the bioassays. This was the first detection of flumethrin resistance in Brazil.


1977 ◽  
Vol 28 (2) ◽  
pp. 345 ◽  
Author(s):  
WJ Roulston ◽  
CA Schuntner ◽  
HJ Schnitzerling ◽  
JT Wilson ◽  
RH Wharton

Three new strains of organophosphorus-resistant cattle tick from central and northern Queensland named Bajool, Tully and Ingham are described. In dosage-mortality tests on larvae they all have relatively low levels of resistance but can be distinguished from one another and from other described strains. The levels of acetylcholinesterase activity in the three strains differ from those previously described, and all have enhanced ability to detoxify either coumaphos or chlorpyrifos or both. The Bajool strain came from a property reporting control difficulties with chlorpyrifos. Larvae were found to have a seven times increased resistance to chlorpyrifos, about 14% of the acetylcholinesterase activity present in the Yeerongpilly susceptible strain, and increased ability to detoxify chlorpyrifos. In spraying trials involving all parasitic stages, 0.025% chlorpyrifos produced mortalities of 92 and > 99% of the Bajool and Yeerongpilly strains respectively. The Tully strain came from a property using ethion, and the larvae had a six times increased reistance to ethion and coumaphos. The level of acetylcholinesterase activity was about 1.6 times that in the Yeerongpilly strain and the larvae had enhanced ability to detoxify coumaphos. Spraying trials with 0.075% ethion and 0.025% coumaphos produced mortalities of about 90 and > 99% in the Tully and Yeerongpilly strains respectively. The Ingham strain came from a property which had experienced control failures with coumaphos, clenpyrin and chlorpyrifos. The larvae had a four to five times increased resistance to coumaphos and chlorpyrifos, an acetylcholinesterase activity level 1.8 times as great as that of the Yeerongpilly strain, and enhanced detoxication of both chlorpyrifos and coumaphos. Spraying trials with the recommended concentrations of acaricides gave mortalities of 83% with chlorpyrifos, 78% with coumaphos and 93% with ethion compared with > 99% for the Yeerongpilly strain with each of these acaricides.


2020 ◽  
Author(s):  
Thomas R Shelite ◽  
Ashanti C Uscanga-Palomeque ◽  
Alejandro Castellanos ◽  
Peter C Melby ◽  
Bruno L Travi

Abstract The rapid detection of novel pathogens necessitates the development of easy-to-use diagnostic tests that can be readily adapted and utilized in both clinical laboratories and field settings. In December of 2019, novel coronavirus, SARS-CoV-2 (2019-nCoV), was isolated from a cluster of pneumonia patients in the Chinese city of Wuhan. The virus rapidly spread throughout the world and the first fatal cases of COVID-19 in the United States occurred in late February. The lack of testing and delay in diagnosis has facilitated the spread of this novel virus. Development of point-of-care diagnostic assays that can be performed in rural or decentralized health care centers to expand testing capacity is needed. We developed a qualitative test based on recombinase-polymerase-amplification coupled with lateral flow reading (RPA-LF) for rapid detection of SARS-CoV-2. The RPA-LF detected SARS-CoV-2 with a limit of detection of 35.4 viral nucleocapsid (N) gene copies/µL. Additionally, the RPA-LF was able to detect 0.25-2.5 copies/µL of SARS-CoV-2 N gene containing plasmid. We evaluated 37 clinical samples using CDC’s N3, N1 and N2 RT-real-time PCR assays for SARS-CoV-2 as reference test. We found a 100% concordance between RPA-LF and RT-qPCR reference test as determined by 18/18 positive and 19/19 negative samples. All positive samples had Ct values between 19-37 by RT-qPCR. The RPA-LF primers and probe did not cross react with other relevant betacoronaviruses such as SARS and MERS. This is the first isothermal amplification test paired with lateral flow developed for qualitative detection of COVID-19 allowing rapid viral detection and with prospective applicability in resource limited and decentralized laboratories.


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