title: Fatal Theileria orientalis N2 genotype infection among Asian water buffaloes (Bubalus bubalis) in a commercial dairy farm in Kerala, India.
abstract: Fifteen dairy buffaloes of a farm in the state of Kerala, India developed fatal oriental theileriosis within 2 months of their procurement. Typical piroplasms of Theileria orientalis were observed in the erythrocytes of all affected animals by Giemsa-Leishman staining of blood smears. Case fatality rate was 87·5% (seven out of eight) in the clinically progressed cases. Therapeutic management with anti-theilerial drugs buparvaquone and oxytetracycline led to recovery of seven other animals in less advanced stages of the disease. The aim of this study was to determine the reasons for increased virulence of this pathogen, hitherto considered to be benign. Acute haemolytic anaemia was the predominant haematological finding in the affected animals. Lymphocytic infiltration and degeneration of vital organs leading to functional derangement was the cause of the high mortality. Identification of T. orientalis was confirmed by polymerase chain reaction (PCR). DNA sequencing of the PCR products revealed close identity with already reported sequences of T. orientalis/buffeli N2 genotype. The sequences were deposited in GenBank with accession number KM609973 and KM043772. Rhipicephalus ticks, previously not reported as vectors for oriental theileriosis, were identified as the potential vectors. This is the first report of fatal oriental theileriosis in Asian water buffaloes.
authors.affiliation: Department of Veterinary Epidemiology and Preventive Medicine,College of Veterinary and Animal Sciences,Mannuthy,Trichur,Kerala, 680651,India.
authors.forename: Kulangara
authors.initials: K
authors.lastname: Vinodkumar
authors.affiliation: Department of Veterinary Epidemiology and Preventive Medicine,College of Veterinary and Animal Sciences,Mannuthy,Trichur,Kerala, 680651,India.
authors.forename: Varikkottil
authors.initials: V
authors.lastname: Shyma
authors.affiliation: Department of Veterinary Epidemiology and Preventive Medicine,College of Veterinary and Animal Sciences,Mannuthy,Trichur,Kerala, 680651,India.
authors.forename: Davis Kollannur
authors.initials: DK
authors.lastname: Justin
authors.affiliation: Department of Veterinary Epidemiology and Preventive Medicine,College of Veterinary and Animal Sciences,Mannuthy,Trichur,Kerala, 680651,India.
authors.forename: Sivasailam
authors.initials: S
authors.lastname: Ashok
authors.affiliation: Department of Veterinary Epidemiology and Preventive Medicine,College of Veterinary and Animal Sciences,Mannuthy,Trichur,Kerala, 680651,India.
authors.forename: Joseph Parassery
authors.initials: JP
authors.lastname: Anu
authors.affiliation: Department of Veterinary Epidemiology and Preventive Medicine,College of Veterinary and Animal Sciences,Mannuthy,Trichur,Kerala, 680651,India.
authors.forename: Kattilveetil
authors.initials: K
authors.lastname: Mini
authors.affiliation: Department of Veterinary Epidemiology and Preventive Medicine,College of Veterinary and Animal Sciences,Mannuthy,Trichur,Kerala, 680651,India.
authors.forename: Varikkottil
authors.initials: V
authors.lastname: Muhammedkutty
authors.affiliation: Department of Veterinary Epidemiology and Preventive Medicine,College of Veterinary and Animal Sciences,Mannuthy,Trichur,Kerala, 680651,India.
authors.forename: Suchithra
authors.initials: S
authors.lastname: Sasidharan
authors.affiliation: Department of Veterinary Epidemiology and Preventive Medicine,College of Veterinary and Animal Sciences,Mannuthy,Trichur,Kerala, 680651,India.
authors.forename: Sunanda
authors.initials: S
authors.lastname: Chullipparambil
mesh_terms: D000818:Animals; D001483:Base Sequence; D002020:Buffaloes / Q000469:parasitology*; D003612:Dairying; D004196:Disease Outbreaks / Q000662:veterinary; D005260:Female; D005838:Genotype; D007194:India / Q000453:epidemiology; D007303:Insect Vectors / Q000469:parasitology*; D008969:Molecular Sequence Data; D010802:Phylogeny; D016133:Polymerase Chain Reaction / Q000662:veterinary; D048494:Rhipicephalus / Q000469:parasitology*; D017422:Sequence Analysis, DNA / Q000662:veterinary; D016794:Theileria / Q000235:genetics / Q000302:isolation & purification*; D013801:Theileriasis / Q000453:epidemiology* / Q000469:parasitology
keywords: Asian water buffaloes; Theileria orientalis; fatal outbreak; genotype; pathology