Introduction
Neonatal diarrhea (ND) is a common occurrence on Canadian pig farms. The cause of neonatal diarrhea in piglets is often multifactorial; many infectious pathogens can contribute to diarrhea. This includes E. coli, Clostridium perfringens type A and C (CpA & CpC), Clostridioides difficile (C. difficile), Rotavirus, and Porcine Epidemic Virus (PED)1
. However, the prevalence of C. difficile and CpA on Canadian pig farms has not been
recently investigated. C. difficile causes diarrhea in piglets less than 7 days of age, with high morbidity and variable mortality2. CpA is a normal inhabitant of the pig’s intestinal microbiota and has also been implicated as a cause of diarrhea in neonatal piglets3. Understanding the prevalence of C. difficile and CpA would allow for better control of
ND on Canadian farms.
Materials and methods
Piglets on 54 Canadian farms with ND were sampled with rectal swabs (Ontario [n=22], Quebec [n=11], West [n=21]). Testing was done by using Enterocheck kits, an FTA-card diagnostic kit based on PCR testing. Cycle threshold (Ct) values were determined, and the presence of A and B toxins of C. difficile were considered relevant when Ct value <30 and
α-toxin of CpA was considered relevant with Ct-value <26
Results
84.94% of the farms tested positive for C. difficile A toxin with high positivity on 41.57% of farms. In addition, 31.93% of the farms tested positive for C. difficile B toxin, with a high positivity on 2.41% of farms. It is noteworthy that both toxins A and B were coinfecting in 32% of the fecal samples. For C. perfringens, 100% of the farms tested positive for α
toxin, with high positivity (Ct<26) on 69.28% of farms (Figure 1). The most prevalent virulence factors of E. coli were F4 and LT toxin with 41% and 19% of positivity, respectively. 19 farms were also sampled against Rotavirus A and C, showing a 78.9% and 52.6% of positivity correspondingly.
Discussion & Conclusion
This study demonstrates that C. difficile and CpA are both highly prevalent on Canadian pig farms. Also, with high positivity C. difficile and CpA need to be considered as potential primary pathogens in cases of ND. Identifying C. difficile and CpA to implement control strategies, such as vaccination, can help reduce ND on Canadian farms which is
causing financial losses and increase antimicrobial use.
References
1. Vidal A, Martín-Valls GE, Tello M, Mateu E, Martín M, Darwich L. 2019. Prevalence of
enteric pathogens in diarrheic and non-diarrheic samples from pig farms with neonatal
diarrhea in the North East of Spain. Vet Microbiol.
2. Grześkowiak ŁM, Pieper R, Huynh HA, Cutting SM, Vahjen W, Zentek J. Impact of early-life events on the susceptibility to Clostridium difficile colonisation and infection in the
offspring of the pig. Gut Microbes. 2019;10(2):251-259.
3. Chan G, Farzan A, Soltes G, Nicholson VM, Pei Y, Friendship R, Prescott JF. The
epidemiology of Clostridium perfringens type A on Ontario swine farms, with special
reference to cpb2-positive isolates. BMC Vet Res. 2012 Sep 4;8:156.
