Serological and molecular diagnostic surveys combined with examining hematological profiles suggests increased levels of infection and hematological response of cattle to babesiosis infections compared to native buffaloes in Egypt.

Mona S Mahmoud,Soad M Nasr,Omnia M Kandil,Seham H.M Hendawy,Carlos E Suarez,Salwa M Habeeb,Marta G Silva,Dalia M Mabrouk

doi:10.1186/s13071-015-0928-9

Mona S Mahmoud, Soad M Nasr + Show 6 more

Open Access

https://doi.org/10.1186/s13071-015-0928-9

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Journal: Parasites & Vectors	Publication Date: Jun 12, 2015
Citations: 67	License type: CC BY 4.0

Affiliation: Washington State University

Abstract

BackgroundBabesiosis threatens the development of the cattle and buffaloes industries in Egypt and improved control is needed. The main objectives of this study are surveying the presence of bovine babesiosis in distinct selected bovine and buffalo populations in Egypt using novel molecular and previously validated serological methods, while also comparing the occurrence of hematological alterations among Babesia infected cattle and buffalos.MethodsA total of 253 and 81 blood samples from apparently healthy cattle and buffaloes, respectively, were randomly collected from diverse locations in Egypt. All samples were tested for Babesia bovis and B. bigemina infection using blood film examination, competitive ELISA (cELISA) and PCR. Novel semi-nested and nested PCR assays for the detection of B. bovis and B. bigemina respectively, were developed and used to analyze DNA extracted from bovine and buffalo samples. Hematological profiles were studied using a hematological analyzer.ResultsBlood films examination revealed 13.8 % and 7.4 % Babesia infection rates in cattle and buffaloes, respectively. However, in cattle, the cELISA detected 32.8 %, 21.3 % and 10.7 % infection rates with B. bigemina, B. bovis and mixed infection, respectively. In addition, cELISA identified 22.2 %, 22.2 % and 6.2 % infection rates with B. bigemina, B. bovis and mixed infection, respectively in buffaloes. The semi-nested PCR assay showed that 15 % of the tested samples were positive for B. bovis in cattle, but just 3 % in buffaloes. Infections with B. bigemina were also found in cattle (32.4 %), but not in buffaloes upon nested PCR analysis. Sequencing analysis confirmed the identity of the PCR amplicons and showed that Egyptian genotypes of B. bigemina and B. bovis highly resemble sequences previously deposited in GenBank. Hemograms performed on the sampled animals revealed macrocytic hypochromic anemia associated with reduced platelet counts in infected cattle with babesiosis. In addition, marked increases in total leukocyte and granulocytic counts and decreases in lymphocytic counts were found in infected cattle. In contrast, no such hematological anomalies were found in presumably Babesia-infected buffaloes.ConclusionsFrequent occurrence of babesiosis among apparently healthy bovines in Egypt, suggests the need for appropriately designed prevalence studies in this country. Infected bovine, but not buffalo, populations often present hematological disorders compatible with intravascular hemolysis and thrombocytopenia.

Highlights

Babesiosis threatens the development of the cattle and buffaloes industries in Egypt and improved control is needed
Diagnosis of bovine babesiosis using direct blood film microscopic examination We examined a total of 253 cattle and 81 buffaloes’ microscopic stained slide samples
Serological diagnosis of bovine and buffalo babesiosis using competitive ELISA (cELISA) We performed cELISA tests for the detection of B. bovis and B. bigemina antibodies on serum samples obtained from the 253 bovines and 81 buffaloes as described above

Summary

Introduction

Babesiosis threatens the development of the cattle and buffaloes industries in Egypt and improved control is needed. In Egypt, bovine babesiosis is caused mainly by Babesia bovis and Babesia bigemina. Because of its significant economic impact on meat and milk production and on livestock management, it is currently considered as the most important endemic parasitic disease affecting cattle in Egypt [5]. Both B. bigemina and B. bovis are capable of causing acute disease resulting in lifethreatening hemolytic anemia as well as other severe clinical manifestations [7, 8]. There is a paucity of information on the overall impact that these hematological disorders may have in the development of cattle and buffalo industries in Egypt. Clinical evidence suggests that buffaloes are likely more tolerant to Babesia infections [10], the hematological response of buffaloes to Babesia infection in Egypt remains poorly investigated [10, 11]

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