Comparison of Diagnostic Tests for Detection of Bovine Rotavirus a in Calf Feces

Abstract

Bovine rotavirus A (BRVA) is a frequent causative agent of diarrhea in neonatal calves. Accurate and rapid diagnosis is crucial to prevent calf mortality from BRVA induced diarrhea. Currently, variety of diagnostic methods are being used to detect BRVA from calves’ feces: antibody-based rapid test and ELISA, and molecular-based RT-PCR and RT-qPCR. The aim of the study was to evaluate the accuracy (sensitivity and specificity) of the rapid test (Immunochromatography), ELISA, and RT-PCR assays, using RT-qPCR as the gold standard, in detection of BRVA in diarrheic calves’ fecal samples. One hundred (n=100) clinically diarrheic fecal samples were tested with four different diagnostic tools. The percent of samples positive by rapid test, ELISA, RT-PCR and RT-qPCR was 10%, 16%, 17%, and 33%, respectively. The agreement between different assays was 75% to 99%. The highest agreement was observed between ELISA and RT-PCR assay (99%). The lowest agreement was recorded (75%) between rapid test and RT-qPCR. The sensitivity of the rapid test, ELISA, and RT-PCR were 30%, 49%, and 52%, respectively when compared to the reference test (RT-qPCR), whereas specificity was 100% for all assays. In conclusion, none of the frequently used diagnostic tests showed a satisfactory level of sensitivity to identify BRVA in calves’ feces. Therefore, the use of a more sensitive rapid test should be used to identify infected calves in field conditions in order to prevent calf mortality from rotaviral diarrhea.

Epidemiological study of Rotavirus infection in the diarrheic neonatal calves

“…The present study showed that 7 (8.54%) of 82 diarrheic fecal samples of investigated calves were positive by ICA. Our result of ICA was lower than those of other studies [1,12,13] in which rate of Rotavirus infection in serologically positive enteric calves by ICA was 15.63%, 12.50% and 10%, respectively.…”

“…Serologically, LAT and ICA are rapid and easy diagnostic tests keeping laboratory viral detection is convenient and simplistic [1]. The current serological tests indicated that 16.74% of fecal samples of examined calves were positive by LAT and this result was higher than result obtained previously [10,11] that indicated that rate of serologically positive calves to Rotavirus infection was 6.76% and 10.83%, respectively.…”

“…Neonatal calf enteritis is a multifactorial syndrome due to interaction between immune status of calves, environment, management, nutrition beside enteropathogens. The later appear to be the cornerstone of neonatal enteritis when the hygienic measures were sublevel [1]. The current work indicated the percentage of Rotavirus infection in enteric neonatal calves was 14.92 % and the majority of serologically positive cases were occurred during the neonatal stage (3 days-4 weeks post parturition) referring to Rotavirus infection is neonates-linked-disease.…”

“…Neonatal enteritis appears to be a major problem of calves' rearing causing a considerable level of economic losses [1]. Escherichia coli is frequently incriminated as an outstanding pathogen causing enteritis in neonatal cattle and buffaloes calves [2].…”

Clinical Study with Rapid Serological Detection of Rotavirus Infection in Diarrheic Neonatal Calves

“…Enteritis in newborn calves is an outstanding problem with an economic dimension to cattle herds [1]. Enormous pathogens were incriminated as an etiologic agent of neonatal calves' enteritis.…”