Date Full Report Received

04/08/2015

Date Abstract Report Received

04/08/2015

Investigation

Institution:
Primary Investigator:

The take-home messages for producers are that simple feedback protocols induce good immunity, protection is durable for months, serology can be improved, and lactogenic immunity appears dependent on anti-spike antibodies. One feedback episode induces protective immunity in sows whether or not clinical illness is observed. Serum antibodies are short-lived and so do not provide a good predictor of protection. IgG is the dominant anti-PEDV antibody isotype in serum and colostrum, whereas IgA is dominant in milk. Thus, ELISA assays need to consider which isotype or both to detect depending on the sample source. Antibody responses in milk are expected to predict protection better than antibody responses in serum. Environmental sampling showed that clean-up could be achieved in 8-12 weeks and was facilitated by feedback protocols that reduced the amount of environmental shedding.