Longitudinal study of bovine rotavirus group A in newborn calves from vaccinated and unvaccinated dairy herds.
Reports of rotavirus excretion in calves usually result from cross-sectional studies, and in face of the conflicting results regarding protection of calves born to vaccinated dams against diarrhea, the aim of the present study was to evaluate rotavirus excretion in dairy calves born to vaccinated or unvaccinated dams, to identify the genotypes of bovine rotavirus group A (RVA) strains isolated from these animals as well as to investigate characteristics of the disease in naturally occurring circumstances throughout the first month of life. Five hundred fifty-two fecal samples were taken from 56 calves, 28 from each farm and, in the vaccinated herd, 11/281 samples (3.91%) taken from six different calves tested positive for RVA while in the unvaccinated herd, 3/271 samples (1.11%) taken from 3 different calves tested positive. The genotyping of the VP7 genes showed 91.2% nucleotide sequence identity to G6 genotype (NCDV strain), and for the VP4 gene, strains from the vaccinated herd were 96.6% related to B223 strain, while strains from the unvaccinated herd were 88% related to P[5] genotype (UK strain). Genotypes found in this study were G6P[11] in the vaccinated herd and G6P[5] in the unvaccinated herd. All calves infected with rotavirus presented an episode of diarrhea in the first month of life, and the discrepancy between the genotypes found in the commercial vaccine (G6P[1] and G10P[11]) and the rotavirus strains circulating in both vaccinated and unvaccinated herds show the importance of keeping constant surveillance in order to avoid potential causes of vaccination failure.
Research Laboratory of the Department of Veterinary Medicine and Surgery, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Via de Acesso Prof. Paulo Donato Castellane, s/n, Jaboticabal, SP, CEP14884-900, Brazil. thaisgrocha@yahoo.com.br.|, Jaboticabal, SP, CEP 14870-720, Brazil. thaisgrocha@yahoo.com.br.
Thaís Gomes
TG
Rocha
Department of Preventive Veterinary Medicine and Animal Health, College of Veterinary Medicine, University of São Paulo (USP), Av. Prof. Dr. Orlando Marques de Paiva, 87, São Paulo, SP, CEP 05508-900, Brazil.
Fernanda Dornelas Florentino
FD
Silva
Department of Preventive Veterinary Medicine and Animal Health, College of Veterinary Medicine, University of São Paulo (USP), Av. Prof. Dr. Orlando Marques de Paiva, 87, São Paulo, SP, CEP 05508-900, Brazil.
Fábio
F
Gregori
Laboratory of Animal Virology, Department of Veterinary Preventive Medicine, Universidade Estadual de Londrina, Celso Garcia Cid Road, PR455 Km 380, P.O. Box 10.011, Londrina, PR, CEP 86057-970, Brazil.
Amauri Alcindo
AA
Alfieri
Department of Preventive Veterinary Medicine, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Via de Acesso Prof. Paulo Donato Castellane, s/n, Jaboticabal, SP, CEP 14884-900, Brazil.
Maria da Glória
MD
Buzinaro
Research Laboratory of the Department of Veterinary Medicine and Surgery, School of Agricultural and Veterinarian Sciences, São Paulo State University (Unesp), Via de Acesso Prof. Paulo Donato Castellane, s/n, Jaboticabal, SP, CEP14884-900, Brazil.
José Jurandir
JJ
Fagliari
D000818:Animals; D000831:Animals, Newborn; D001483:Base Sequence; D002417:Cattle; D002418:Cattle Diseases / Q000517:prevention & control / Q000821:virology*; D003430:Cross-Sectional Studies; D003967:Diarrhea / Q000821:virology; D005243:Feces / Q000821:virology; D005838:Genotype; D008137:Longitudinal Studies; D010802:Phylogeny; D012401:Rotavirus / Q000235:genetics / Q000302:isolation & purification*; D012400:Rotavirus Infections / Q000517:prevention & control / Q000662:veterinary* / Q000821:virology; D022243:Rotavirus Vaccines; D014611:Vaccination / Q000662:veterinary*
D022243:Rotavirus Vaccines
Calf diarrhea; Dairy calves; RVA; Sequencing; VP4 gene; VP7 gene