Advances in the diagnosis of bovine besnoitiosis: current options and applications for control

Abstract Background Besnoitia besnoiti is an Apicomplexan protozoa causative of bovine besnoitiosis, a chronic and debilitating disease of cattle, with a variety of pathological findings that could alter some laboratory parameters. A study was conducted in a bovine besnoitiosis endemically infected dairy herd located in Italy characterized by high intra-herd seroprevalence and cattle with clinical signs of the disease. In the study, alterations in laboratory parameters, i.e. hematological and biochemical parameters, enzyme activities and serum cortisol levels, in Besnoitia besnoiti naturally infected cows were investigated in depth. Methods Laboratory parameters in 107 cows, of which 61 were seronegative and 46 were seropositive to B. besnoiti, including 27 with clinical signs of bovine besnoitiosis, were compared. Generalized linear models were used to evaluate the effect of Besnoitia infection on the considered laboratory parameters. Results Hematological analyses revealed that B. besnoiti infection determined a significant alteration to the leukocyte differential, with a higher percentage of granulocytes and a lower percentage of lymphocytes in seropositive and clinically affected animals (Mann–Whitney U-test, P = 0.022); erythrocyte and platelet counts did not show any difference between the considered groups of cows. Biochemistry tests evidenced that the parasite infection influenced serum protein values in seropositive cows and glutamate dehydrogenase values in clinically affected animals. No or only slight differences were revealed for all of the other biochemical and enzyme activity parameters in B. besnoiti-infected animals. In addition, despite the lack of statistical significance, seropositive and clinically affected cows evidenced higher concentrations of serum cortisol values compared to seronegative animals. Conclusions Although physiological, pathological and farm-related factors could have influenced the results in investigated animals, further studies involving more animals from different farms would be advisable to infer the role of B. besnoiti on these alterations, since laboratory parameters could help veterinarians in the diagnosis of bovine besnoitiosis in cattle.

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Real-time PCR on skin biopsies for super-spreaders’ detection in bovine besnoitiosis.

10.21203/rs.3.rs-37696/v2 ◽

2020 ◽

Author(s):

Christelle Grisez ◽

Leslie Bottari ◽

Françoise Prévot ◽

Jean-Pierre Alzieu ◽

Emmanuel Liénard ◽

...

Keyword(s):

Real Time ◽

Control Strategy ◽

Real Time Pcr ◽

Treatment Success ◽

Acute Stage ◽

Besnoitia Besnoiti ◽

Skin Sample ◽

Production Type ◽

Bovine Besnoitiosis ◽

Skin Biopsies

Abstract Background: Bovine besnoitiosis, an emerging disease in Europe that can be transmitted by vectors, is caused by the Apicomplexa Besnoitia besnoiti. Bovine besnoitiosis is difficult to control due to the complexity of its diagnosis in the acute stage of the disease, poor treatment success and chronically asymptomatic cattle acting as parasite reservoirs. When serological prevalence is low, detection and specific culling of seropositive cattle is feasible; however, economic considerations preclude this approach when serological prevalence is high. The aims of this study were to evaluate the accuracy of detection of super-spreaders in highly infected herds and to test their selective elimination as a new control strategy for bovine besnoitiosis. Methods: Previous real-time PCR analyses performed on skin tissues from 160 asymptomatic animals sampled at slaughterhouses showed that the tail base was the best location to evaluate the dermal parasite DNA load. All seropositive animals (N = 518) from eight dairy or beef cattle farms facing a high serological prevalence of besnoitiosis were sampled at the tail base and their skin sample analysed by real-time PCR. A recommendation of rapid and selective culling of super-spreaders was formulated and provided to the cattle breeders. Subsequent serological monitoring of naïve animals was used to evaluate the interest of this control strategy over time.Results: Among the 518 seropositive animals, a low proportion of individuals (14.5%) showed Ct values below 36, 17.8% had doubtful results (36 < Ct ≤ 40) and 67.8% had negative PCR results. These proportions were grossly similar on the eight farms, regardless of their production type (beef or dairy cattle), size, geographic location or history of besnoitiosis. Within two weeks of the biopsy, the rapid culling of super-spreaders was implemented on only three farms. The numbers of newly infected animals were lower on these farms compared to those where super-spreaders were maintained in the herd. Conclusions: Real-time PCR analyses performed on skin biopsies of seropositive cattle showed huge individual variabilities in parasite DNA load. The rapid culling of individuals considered as super-spreaders seems to be a new and encouraging strategy for bovine besnoitiosis control.

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Molecular survey of Besnoitia spp. (Apicomplexa) in faeces from European wild mesocarnivores in Spain. Short running title: Molecular survey of Besnoitia spp in faeces from wild carnivores.

10.22541/au.162083175.56553530/v1 ◽

2021 ◽

Author(s):

David González-Barrio ◽

Pamela C. Köster ◽

Miguel Habela ◽

Manuel Martín-Pérez ◽

José Fernández-García ◽

...

Keyword(s):

Definitive Host ◽

Red Foxes ◽

Besnoitia Besnoiti ◽

Free Living ◽

Wild Carnivores ◽

Molecular Survey ◽

Faecal Samples ◽

Bovine Besnoitiosis ◽

Western Spain ◽

Free Ranging

Numerous studies have unsuccessfully tried to unravel the definitive host of the coccidian parasite Besnoitia besnoiti. Cattle infections by B. besnoiti cause a chronic and debilitating condition called bovine besnoitiosis that has emerged in Europe during the last two decades, mainly due to limitations in its control associated to the absence of vaccines and therapeutical tools. Although the exact transmission pathway of B. besnoiti is currently unknown, it is assumed that the parasite might have an indirect life cycle with a carnivore as definitive host. Current lack of studies in wildlife might underestimate the importance of free-living species in the epidemiology of B. besnoiti. Thus, the aim of the present study is to assess the presence of Besnoitia spp. in free-ranging mesocarnivores in Spain. DNA was searched by PCR on faeces collected from wild carnivores as a first approach to determine which species could be considered as potential definitive host candidates in further research. For this purpose, a total of 352 faecal samples from 12 free-living wild carnivore species belonging to the Canidae, Felidae, Herpestidae, Mustelidae, Procyonidae, and Viverridae families were collected in seven Spanish regions. PCR testing showed that Besnoitia spp. DNA was present in four faecal samples from red foxes collected in western Spain, an area with the greatest density of extensively reared cattle and associated to high incidence of bovine besnoitiosis in the country. To date, this is the first report of a Besnoitia besnoiti-like sequence (99.57% homology) from carnivore faeces in a worldwide context. Red foxes might contribute to the epidemiology of B. besnoiti, although further studies, mostly based on bioassay, would be needed to elucidate the accuracy and extent of these interesting findings.

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Added value of IgM detection and low avidity index as markers of acute bovine besnoitiosis

Veterinary Parasitology ◽

10.1016/j.vetpar.2019.109012 ◽

2020 ◽

Vol 277 ◽

pp. 109012 ◽

Cited By ~ 1

Author(s):

Carlos Diezma-Díaz ◽

Ignacio Ferre ◽

Begonia Saldias ◽

Javier Blanco-Murcia ◽

Luis Miguel Ortega-Mora ◽

...

Keyword(s):

Added Value ◽

Avidity Index ◽

Bovine Besnoitiosis

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First confirmed case of bovine besnoitiosis in Rwanda

Veterinary Parasitology Regional Studies and Reports ◽

10.1016/j.vprsr.2019.100294 ◽

2019 ◽

Vol 17 ◽

pp. 100294

Author(s):

Gervais Habarugira ◽

Charles Nkuranga ◽

Benon Asiimwe ◽

Jean Bosco Turikumwenayo ◽

Lonzy Ojok

Keyword(s):

Bovine Besnoitiosis

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Draft Genome Sequence and Annotation of the Apicomplexan Parasite Besnoitia besnoiti

Genome Announcements ◽

10.1128/genomea.01200-17 ◽

2017 ◽

Vol 5 (46) ◽

Cited By ~ 3

Author(s):

Gereon Schares ◽

Pratap Venepally ◽

Hernán A. Lorenzi

Keyword(s):

Genome Sequence ◽

Causative Agent ◽

Definitive Host ◽

Draft Genome ◽

Sequence Assembly ◽

Apicomplexan Parasite ◽

Draft Genome Sequence ◽

Besnoitia Besnoiti ◽

Genome Sequence Assembly ◽

Bovine Besnoitiosis

ABSTRACT The apicomplexan parasite Besnoitia besnoiti is the causative agent of bovine besnoitiosis that affects livestock, particularly cattle. The definitive host of B. besnoiti is unknown and its transmission only partially understood. Here, we report the first draft genome sequence, assembly, and annotation of this parasite.

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First highly sensitive and specific competitive ELISA for detection of bovine besnoitiosis with potential as a multi-species test

International Journal for Parasitology ◽

10.1016/j.ijpara.2019.12.010 ◽

2020 ◽

Vol 50 (5) ◽

pp. 389-401

Author(s):

Gereon Schares ◽

Daniela Nascimento ◽

Andrea Bärwald ◽

Charles Jutras ◽

Stephane Rivard ◽

...

Keyword(s):

Competitive Elisa ◽

Highly Sensitive ◽

Bovine Besnoitiosis

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From the mainland to Ireland – bovine besnoitiosis and its spread in Europe

Veterinary Record ◽

10.1136/vr.i3175 ◽

2016 ◽

Vol 178 (24) ◽

pp. 605-607 ◽

Cited By ~ 5

Author(s):

Gema Álvarez-García

Keyword(s):

Bovine Besnoitiosis

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Biting behaviour of Tabanidae on cattle in mountainous summer pastures, Pyrenees, France, and effects of weather variables

Bulletin of Entomological Research ◽

10.1017/s0007485314000170 ◽

2014 ◽

Vol 104 (4) ◽

pp. 471-479 ◽

Cited By ~ 14

Author(s):

F. Baldacchino ◽

L. Puech ◽

S. Manon ◽

Lionel R. Hertzog ◽

P. Jay-Robert

Keyword(s):

Mixed Models ◽

Climatic Conditions ◽

Weather Variables ◽

Protection Measures ◽

Defensive Reaction ◽

Feeding Sites ◽

Wind Speeds ◽

Bovine Besnoitiosis ◽

Biting Behaviour ◽

Observation Period

AbstractIn France, during the summer, cattle in mountainous pastures can be highly exposed to tabanid bites. The persistent biting behaviour of tabanids not only causes disturbance, but is also responsible for transmitting diseases, such as bovine besnoitiosis. The purpose of this study was to better identify the level of tabanid annoyance on cattle by means of insect trapping and direct observation of cows. Tabanids were active during the entire daily observation period (10:00–16:00), except for Haematopota sp., which were less active in the morning. The tabanids collected in Nzi traps were generally representative of those that landed on cattle, except for Haematopota sp., as Nzi traps were not very effective for these species. The preferred feeding sites for most species appeared to be cow's legs or udder. Leg stamping was the defensive reaction most related to a tabanid alighting on a host. Generalized linear mixed models showed that the parameters associated with tabanid landings on hosts were related to weather and altitude, but not to landscape structure. Increased landings were mostly associated with the higher temperatures and lower wind speeds at midday, but some differences were observed between species. The results indicate that cattle-protection measures should be taken during the peak of tabanid abundance when climatic conditions favour intense biting activity. Nzi traps set close to livestock were very effective to catch tabanids and could help in reducing the annoyance caused by horse flies.

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