Cryptosporidium parvum (C. parvum)-caused calf diarrhoea (scours) is widespread and leads to calf mortality in cattle industries worldwide. A recent discovery of a glycopeptide epitope on the Cryptosporidium parasite recognized by a monoclonal antibody has led to the development of a new vaccine. It was designed for cows to pass on passive immunity to their neonatal calves. This vaccine has been demonstrated to be safe and efficacious in pre-clinical studies. In the process of marketing registration, two clinical studies were conducted with this vaccine on 16 commercial dairy and beef farms collecting data, assessed by the European Medicine Agency. In these studies, its effectiveness in the field was evaluated. The natural challenge and clinical disease caused by Cryptosporidium parvum in the calves in these studies was, however, not high enough to show a significant reduction of most of the clinical signs, although all trends were in favour of the vaccination groups. Nonetheless, the duration of the diarrhoea episodes of the dairy calves was significantly shorter in the vaccination group. Additionally, the levels of Gp40 antibodies in the blood of the calves was notably higher in the vaccination groups, demonstrating the principle of passive immunization. Overall, this vaccine, which can be used concurrently, non-mixed with Bovilis^® Rotavec^® Corona, introduces an additional approach to mitigate the impact of C. parvum infections in neonatal calves.

A commercial pig farm with no history of porcine circovirus 2 (PCV2) or porcine reproductive and respiratory syndrome virus (PRRSV) repeatedly reported a significant reduction in body weight gain and wasting symptoms in approximately 20–30% of the pigs in the period between three and six weeks after weaning. As standard clinical interventions failed to tackle symptomatology, viral metagenomics were used to describe and monitor the enteric virome at birth, 3 weeks, 4 weeks, 6 weeks, and 9 weeks of age. The latter four sampling points were 7 days, 3 weeks, and 6 weeks post weaning, respectively. Fourteen distinct enteric viruses were identified within the herd, which all have previously been linked to enteric diseases. Here we show that wasting is associated with alterations in the enteric virome of the pigs, characterized by: (1) the presence of enterovirus G at 3 weeks of age, followed by a higher prevalence of the virus in wasting pigs at 6 weeks after weaning; (2) rotaviruses at 3 weeks of age; and (3) porcine sapovirus one week after weaning. However, the data do not provide a causal link between specific viral infections and the postweaning clinical problems on the farm. Together, our results offer evidence that disturbances in the enteric virome at the preweaning stage and early after weaning have a determining role in the development of intestinal barrier dysfunctions and nutrient uptake in the postweaning growth phase. Moreover, we show that the enteric viral load sharply increases in the week after weaning in both healthy and wasting pigs. This study is also the first to report the dynamics and co-infection of porcine rotavirus species and porcine astrovirus genetic lineages during the first 9 weeks of the life of domestic pigs.