Viral gastroenteritis in pigs: current knowledge and challenges

Sa？etak Viral gastroenteritis in pigs is a continuous challenge for pig breeders, from the aspects of health management and the implementation of adequate biosecurity measures. The most important pathogens in its aetiology are coronaviruses and rotaviruses, having features such as excretion in high concentrations, low infective dose, extreme environmental stability and high contagiousness. Coronaviruses are the causative agents of important epizootics with high mortalities in nursing piglets (up to 100%), in particular the porcine epidemic diarrhoea virus (PEDV), which recently caused substantial losses for pig breeders in Croatia and worldwide. Apart from PEDV, notable coronaviruses in pigs are transmissible gastroenteritis virus (TGEV), porcine deltacoronavirus (PDCoV) and the recently described swine acute diarrhoea syndrome-coronavirus (SADS-CoV). Rotaviruses are also significant pathogens causing diarrhoea in young pigs, even though they are ubiquitous, with Rotavirus A (RVA) being the most important species among five rotavirus species known to circulate in pigs. Rotaviruses are known to possess a zoonotic potential which is also speculated for porcine deltacoronavirus, nevertheless coronaviruses of pigs have not yet been detected in humans. The example of SADS-CoV transmission from bats to pigs emphasizes the need for surveillance of wild animals known as a source of diseases that present a veterinary and public health threat. The pathogenesis, clinical appearance, autopsy and pathohistological findings are similar for all viral gastroenteritis in pigs. In case of an outbreak of watery and yellowish diarrhoea of high morbidity and mortality, especially in nursing piglets, the suspicion of viral aetiology is warranted. Therefore, early diagnosis is key for the implementation of adequate measures to prevent the disease from spreading and causing substantial losses. The therapy is only supportive and vaccines are not available on this market, therefore the control of these viral infections is based on good health management and the implementation of strict hygiene and sanitary measures, as well as internal and external biosecurity measures