Vaccine-related protection against PCV2 fetal infection in conventional gilts

摘要

From our previous investigations a low antibody titre and a prolonged viraemia in non-vaccinated compared to vaccinated gilts revealed to be the higher risk factor associated to foetus infection in conventional animals inseminated with PCV2 spiked semen.3 PCV2 is involved in reproductive failure in swine that includes clinical and subclinical form.2 The former is characterized by early termination of pregnancy, increased numbers of mummified foetuses, still born or weak-born piglets, microscopic lesions within foetal tissues (heart, liver or lymphoid tissues) and PCV2 antigen or PCV2 DNA within foetal tissues. In contrast, subclinical PCV2 in utero infection is identified by the detection of PCV2 DNA or specific antibodies in foetal tissues, pre-suckling serum or foetal thoracic fluid without the presence of microscopic lesions or indication of reproductive failure.2 For these reasons, it is important to collect data on the protective role of PCV2 vaccination against this two clinical entities.