Pathogens Detected in 205 German Farms with Porcine Neonatal Diarrhea in 2017

Abstract

Neonatal diarrhea (ND) is still a frequently observed problem in modern industrial pig production. ND is predominantly caused by bacterial and viral pathogens. The objective of this study was to give an overview of different pathogens involved in ND in Germany. In 2017, a total number of 555 litters from 205 German pig farms with clinical ND were sampled with pooled fecal samples. All samples were analyzed regarding bacterial pathogens by culture and viral pathogens by polymerase chain reaction (PCR). Isolated strains of Clostridium (C.) perfringens, Escherichia (E.) coli, and C. difficile were further characterized by molecular techniques (e.g., PCR). There were 200 litters (36%), out of 555 sampled litters of 205 farms, which were positive for at least one, while most of them were positive for two or more pathogens. Toxin-producing C. perfringens type A could be detected in 122 farms (59.2%), C. difficile in 116 (56.1%), pathogenic E. coli in 79 (38.6%), and Rotavirus type A in 72 (35%). Among E. coli isolates, enterotoxigenic (8.8%) (F4 fimbriae positive (60.0%)) and necrotoxigenic E. coli (5.3%) were the most frequently detected pathotypes. In conclusion, in most of the farms with porcine ND it turned out to be a disease mainly caused by multiple pathogens, predominantly C. perfringens type A, pathogenic E. coli, and Rotavirus type A. Nevertheless, C. difficile and necrotoxigenic E. coli might be emerging pathogens in ND.

Co-infection of porcine epidemic diarrhea virus and Clostridium perfringens type A enhances disease severity in weaned pigs

“…Furthermore, more than 80% of the CPA isolates that encode the cpa (α-toxin) and cpb2 (β2-toxin) genes can be virulent or potentially virulent. Comparable to recent studies [3,22,23], our data also supported that the toxin-producing CPA was the most frequently detected type of C. perfringens in pre-and post-weaning diarrhea. By contrast, CPC is less commonly involved in neonatal diarrhea, albeit it causes highly fatal necrohemorrhagic enteritis [4].…”

“…In this regard, post-weaning pigs with PEDV single-infection or coinfection that cannot approach suitable slaughter weights at a certain age is not favorable for the swine industry. C. perfringens is a part of the pig intestinal microbiome and is considered an enteric bacterial pathogen in pre-and post-weaning piglets [3,22,23]. However, whether C. perfringens is involved in diarrheal disease in domestic pig farms is still unclear.…”

“…C. perfringens isolated from pigs is divided into ve toxinotypes (A-E) based on the ability to produce a combination of six toxins: α-(cpa), β1-(cpb), β2-(cpb2), entero-(cpe), ε-(etx), and ι-toxins (iap) [2]. Although all types of C. perfringens can be found generally in the gastrointestinal tract of piglets, only C. perfringens types A (CPA) and C (CPC) are considered pathogenic in nursing pigs [3]. In particular, CPA is the most frequently detected bacterial pathogen in porcine neonatal diarrhea [3,4].…”

“…Although all types of C. perfringens can be found generally in the gastrointestinal tract of piglets, only C. perfringens types A (CPA) and C (CPC) are considered pathogenic in nursing pigs [3]. In particular, CPA is the most frequently detected bacterial pathogen in porcine neonatal diarrhea [3,4].…”

“…The suspensions were vortexed and centrifuged for 10 min at 4,500 × g (Hanil Centrifuge FLETA5, Incheon, South Korea). The clari ed supernatants were initially subjected to conventional PCR for the detection and typing of C. perfringens as described previously [2,3]. To determine if any other diarrhea-causing viral pathogens were present in clinical samples, we performed virus-speci c RT-PCR analyses for PEDV, transmissible gastroenteritis virus (TGEV), porcine deltacoronavirus (PDCoV), and porcine rotaviruses (PRV), as described previously [14,15,16].…”