The Studies on the Aetiology of Diarrhoea in Neonatal Calves and Determination of Virulence Gene Markers ofEscherichia coliStrains by Multiplex PCR

Abstract

The purpose of this study was to determine aetiological agents of diarrhoea in neonatal calves and to investigate virulence gene markers of Escherichia coli strains isolated from calves by multiplex polymerase chain reaction (PCR). Eighty-two diarrhoeic calves and 18 healthy calves were used as subjects. Faeces were taken from the rectums of all the calves and were subjected to bacterial culture. Antigen enzyme-linked immunosorbent assay (ELISA) was performed to detect rotavirus, coronavirus and E. coli K99 in faeces of all the calves. A multiplex PCR was used to characterize E. coli strains in all the calves. Escherichia coli was isolated from 37 faeces samples, Enterococcus ssp. was isolated from 22 faeces samples and Salmonella was isolated from one faeces sample in diarrhoeic calves. Furthermore, only E. coli was isolated from all 18 faeces samples of healthy calves. Of the 37 E. coli isolated from diarrhoeic calves, K99 (18.9%), F41 (18.9%), heat-stable enterotoxin a (STa) (18.9%), Shiga toxin 1 (Stx1; 13.5%) and Shiga toxin 2 (Stx2; 5.4%) and intimin (8.1%) genes were identified by multiplex PCR. Of the 18 E. coli isolated from healthy calves, K99 (16.6%) and intimin (55.5%) genes were identified by PCR. A total of 15 rotavirus, 11 coronavirus and 11 E. coli K99 were detected in diarrhoeic calves by the antigen ELISA. As a result, this study shows that rotavirus, coronavirus, E. coli and Enterococcus ssp. were determined to play a role in the aetiology of diarrhoea in the neonatal calves. K99, F41, STa, Stx1 and Stx2 were found as the most common virulence gene markers of E. coli strains isolated from calves with diarrhoea. Multiplex PCR may be useful for characterization of E. coli isolated from calves.

<i>Escherichia coli</i> Isolates from Calf Diarrhea in Korea and Their Virulent Genetic Characteristics

“…K99 and/or F41 fimbriae, the major adhesion factors, mediate adherence to the ileum [3,12] and have been found in most E. coli isolates from diarrheic calves [3,10]. In this study, however, fanC and fim41a, the genes for F4 and F41 fimbriae, were detected in 9.9 and 8.3%, respectively, which are relatively lower rates compared to those previously reported [3,12,14]. Recently, the F17 fimbrial family has been known to be prevalent in PEC strains isolated from calves with diarrhea or septicemia [12,15].…”

“…Although virulence factors such as intimin and Shiga toxins are associated with diarrhea in calves [12,13], the virulence factors are in high rate isolated from feces of healthy calves and cattle [3,5,14,16]. However, the strain containing virulence factors of Shiga toxins and intimin are associated with cases of gastroenteritis in humans, which could progress to hemorrhagic colitis and hemolytic uremic syndrome [4,13].…”

Hemato-biochemical and therapeutic studies on Escherichia coli associated with concurrent enteric infection in lambs

“…Epidemiological studies on the 'Guidelines for Animal Experimentation' approved diarrhoea in lambs have shown that Escherichia coli is by the Institutional Animal Care Committee. an important cause of neonatal mortality [2,3].…”

Acid-base disorders in calves with chronic diarrhea

“…The cryptosporidial colonization of the small and large intestine results in destruction of enterocytes. Contrary to isolated bacterial or viral infections, mixed infections with C. parvum are associated with shortening of intestinal villi and persistent severe disorders of digestion and absorption (Coutinho et al 2008, Ok et al 2009). …”

“…While the diarrhea of neonatal calves is usually associated with bacterial (E. coli) or rotaviruses and coronaviruses infections, Cryptosporidium spp. seems to be the most common cause of diarrhea in older, 3-week-old animals (Coutinho et al 2008, Foster and Smith 2009, Ok et al 2009). Clinical signs of diarrhea include loose watery stools, lack of appetite and abdominal pain.…”