Causative agents and epidemiology of diarrhea in Korean native calves

Abstract

Calf diarrhea caused by infectious agents is associated with economic losses in the cattle industry. The purpose of this study was to identify the causative agents and epidemiological characteristics of diarrhea in Korean native calves (KNC). In total, 207 diarrheal KNC aged less than 7 months were investigated. Fecal samples collected from the rectum were examined for causative agents using polymerase chain reaction (PCR) or real-time PCR and the number of oocysts were counted. Fourteen causative agents were detected from 164 of the 207 diarrheal KNC. Rotavirus was the most common agent (34.8%), followed by Eimeria spp. (31.7%), Escherichia coli (22.0%), Giardia spp. (14.0%), Clostridium difficile (9.8%), bovine viral diarrhea virus (8.5%), coronavirus (7.9%), Cryptosporidium spp. (7.3%), torovirus (6.7%), parvovirus (5.5%), norovirus (4.9%), kobuvirus (1.8%), adenovirus (1.2%), and Salmonella spp. (0.6%). About 95 (57.9%) of 164 calves were infected with a single causative agent and 42.1% were infected by multiple agents. No significant difference was observed in mortality between calves infected with a single agent and multiple agents. The occurrence of diarrhea caused by rotavirus, Eimeria spp., kobuvirus, and Giardia spp. was significantly different based on onset age, and the prevalence of diarrhea caused by rotavirus or C. difficile was significantly different between seasons. This study help the understanding of KNC diarrhea for the development of an effective strategy for disease prevention and control, especially in Eastern provinces of South Korea.

Genes Encoding the Virulence and the Antimicrobial Resistance in Enterotoxigenic and Shiga-toxigenic E. coli Isolated from Diarrheic Calves

“…This study was aimed at determining the prevalence of STEC and ETEC incriminated in calf diarrhea, with special reference to the Shiga-toxins genes ( stx 1 and stx 2) and enterotoxins genes ( lt and sta ) that govern their pathogenesis, as well as the virulence genes; eae A and f 41, and the screening of their antimicrobial resistance profiles and antimicrobial resistance genes; aad B, sul 1, and bla- TEM. The overall prevalence of E. coli was 28.8%, which is lower than what was reported in diarrheic calves in Egypt (63.6%) [ 13 ], Ethiopia (36.8%) [ 14 ], Argentina (30.1%) [ 15 ] and India (85.04%) [ 16 ]; however, a lower prevalence was reported in other previous studies in Korea (22%) [ 17 ] and Switzerland (5.5%) [ 18 ]. Differences in the prevalence of E. coli may be due to the differences in geography, management practices, floor type, health conditions, and the calf’s age [ 2 , 13 , 15 ].…”

The prevalence of causative agents of calf diarrhea in Korean native calves

“…BRV was detected 15.2% in Korean native beef calves and significantly related to diarrhea ( p < 0.001). In other reports in Korea, BRV was detected in 34.8% from diarrhea feces in Korean native calves [ 14 ], which might be come from the difference of regions, research periods, and methodology. However, these results including previous reports demonstrate that rotavirus is an important pathogen that can negatively affect the health of calves, consistent with that of earlier reports [ 13 – 15 ].…”

Investigation and Analysis on the Pathogen of Calf Diarrhea in Henan Province

“…Lee et al [13] detected a total of 14 pathogens in 207cases of diarrhea calves in Korea by PCR. The most common pathogens were BRV (34.8%), E. coli (22.0%), BVDV (8.5%), BCoV (7.9%) and Cryptosporidium (7.3%).…”