Isolation Coronavirus and Rotavirus Associated With Calves, in Central Part of Oromia, Ethiopia

Abstract

Background: Coronavirus and Rotavirus are most commonly associated etiologies for calves’ diarrhea resulting in loss of productivity and economy of farmers. However, various facets of diarrheal disease caused by coronavirus and rotavirus in calves in Ethiopia are inadequately understood. A cross sectional study was conducted with the aim of isolation and molecular characterization of coronavirus and rotavirus from calves in central part of Oromia (Bishoftu, Sebata, Holeta and Addis Ababa), Ethiopia from November 2018 to May 2019. The four study areas were purposively selected and fecal samples were collected by simple random sampling for diagnosis of coronavirus and rotavirus infection by using antigen detection Enzyme linked immunosorbent assay (Ag-ELISA) kit. In addition, this study was carried out to have insight in prevalence and associated risk factors of coronavirus and rotavirus infection in calves. Result: During the study 83 diarrheic and 162 non-diarrheic fecal samples collected from calves less than 4 weeks of age were screened for coronavirus and rotavirus. Of the 83 diarrheic samples, 1 sample (1.2%) was positive for coronavirus antigen (Ag) and 6 samples (7.2%) were found to be positive for rotavirus antigen (Ag) by Ag-ELISA. All the non-diarrheic samples were negative for both coronavirus and rotavirus Ag. The overall prevalence of coronavirus and rotavirus infection in calves were estimated as 0.4% (1/245) and 2.45% (6/245) respectively. All samples (7) of ELISA test positive of both coronavirus and rotavirus were propagated in Madin Darby bovine kidney cells (MDBK). After 3 subsequent passages, progressive cytopathic effect (CPE) i.e. rounding, detachment as well as destruction of mono-layer cell of five sample (1 sample of coronavirus and 4 sample of rotavirus) (71.4%) were observed. At the molecular stage, reverse transcriptase polymerase chain reaction (RT-PCR) technique was used to determine the presence of coronavirus and rotavirus nucleic acid by using specific primers. The 5 samples that were coronavirus and rotavirus antigen positive by ELISA and develop CPE on cell culture were also positive on RT-PCR technique. Infection prevalence peaked have been obtained at 1st and 2nd weeks of age in male calves. Conclusion: Diarrheal disease caused by coronavirus and rotavirus has a great health problem in calves that interrupts production benefits with reduced weight gain and increased mortality, and its potential for zoonotic spread. So the present findings show coronavirus and rotavirus infection in calves in Ethiopia that needs to be addressed by practicing early colostrums feeding in newborn calves, using vaccine, or improving livestock management.

Antigen Detection of Bovine Rotavirus Infection in Diarrheic Crossbred Dairy Calves Reared by Holeta Research Center, Oromiya Region Ethiopia

“…The prevalence of infection was 4.76 % in clinically diarrheic calves and 5.65% in calves without the history of calf scour was notified. This result could also match with the previous findings of Seid [11] who reported the prevalence of 7.23%…”

“…herd; the survival of rotavirus in air and on surfaces is influenced by the air humidity [7]. Limited and fragmented studies so far conducted in Ethiopia indicated that the incidence of neonatal calf diarrhea varies from 20.05% to 52.51% [10] and Seid [11] also reported 33.88% diarrhea and the prevalence of 2.45% rotavirus infection in calves less than four weeks of age. It has been indicated that about 75% of early calf mortality in the dairy herd is caused by acute diarrhea in the pre-weaning period [12].…”

Rotavirus in Calves and Its Zoonotic Importance

“…Another study showed the prevalence of rotavirus 25% in children less than five years in northwest Ethiopia by Gelaw et al [ 67 ]. Only two reports were found in Ethiopia by Abraham et al [ 15 ] and Geletu et al [ 68 ] that indicated presence of 16.7% and 7.2% in calves in central Ethiopia, respectively.…”

“…Diarrheal disease caused by rotavirus poses a great health problem in calves that interrupts production benefits with reduced weight gain and increased mortality, and its potential for zoonotic spread [ 68 ]. Rotavirus is a major pathogen responsible for diarrheal disease in calves resulting in loss of productivity and economy of farmers.…”

Prevalence of Bovine Rotavirus and Coronavirus in Neonatal Calves in Dairy Farms of Addis Ababa, Ethiopia: Preliminary Study

“…A cross-sectional study was conducted from November 2018 to April 2019 among randomly selected 110 neonatal calves in 57 dairy herds. The sample size was calculated using a single population proportion formula (X = Zα/22 * p * ð1 − pÞ/MOE 2 ), considering p = 7:2 [12], d = 0:05, and 10% none response rate (103 + 10 = 113). The calves were selected from 57 dairy herds using a probability proportional to size (PPS) sampling technique, and dairy farms were visited once.…”