Background: The objective of the present study was to explore the benefits of Porcine circovirus 2 (PCV-2) blanket vaccination in a sow herd on productive parameters, PCV-2 infection and immune status in sows and their progeny. For this purpose, 288 sows were distributed among four balanced experimental groups. One group remained as negative control group and the other three received 1 mL of PCV-2 Ingelvac Circoflex® intramuscularly at different productive cycle moments: before mating, mid gestation (42–49 days post-insemination) or late gestation (86–93 days post-insemination); phosphate buffered saline (PBS) was used as negative control item. Reproductive parameters from sows during gestation and body weight of their progeny from birth to weaning were recorded. Additionally, blood was collected from sows at each vaccination time and piglets at 3 weeks of age. Moreover, up to 4 placental umbilical cords (PUC) per sow were taken at peri-partum. Sera from sows and piglets were analysed for PCV-2 antibody detection using an enzyme-linked immunosorbent assay (ELISA). Sera from sows and PUC were tested to quantify viraemia using a real time quantitative polymerase chain reaction (qPCR) assay. Results: Globally, results indicated that vaccinated sows showed heavier piglets at birth and at weaning, less cross-fostered piglets, lower viral load at farrowing as well as in PUC, and higher antibody levels at farrowing, compared to non-vaccinated ones. When all groups were compared among them, sows vaccinated at mid or late gestation had heavier piglets at birth than non-vaccinated sows, and lower proportion of PCV-2 positive PUC. Also, cross-fostering was less frequently practiced in sows vaccinated at pre-mating or mid gestation compared to non-vaccinated ones. Conclusions: In conclusion, the present study points out that PCV-2 sow vaccination at different time points of their physiological status (mimicking blanket vaccination) offers benefits at production and serological and virological levels.

A wide range of animal species are susceptible to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. Natural and/or experimental infections have been reported in pet, zoo, farmed and wild animals. Interestingly, some SARS-CoV-2 variants, such as B.1.1.7/Alpha, B.1.351/Beta, and B.1.1.529/Omicron, were demonstrated to infect some animal species not susceptible to classical viral variants. The present study aimed to elucidate if goats (Capra aegagrus hircus) are susceptible to the B.1.351/Beta variant. First, an in silico approach was used to predict the affinity between the receptor-binding domain of the spike protein of SARS-CoV-2 B.1.351/Beta variant and angiotensin-converting enzyme 2 from goats. Moreover, we performed an experimental inoculation with this variant in domestic goat and showed evidence of infection. SARS-CoV-2 was detected in nasal swabs and tissues by RT-qPCR and/or immunohistochemistry, and seroneutralisation was confirmed via ELISA and live virus neutralisation assays. However, the viral amount and tissue distribution suggest a low susceptibility of goats to the B.1.351/Beta variant. Therefore, although monitoring livestock is advisable, it is unlikely that goats play a role as SARS-CoV-2 reservoir species, and they are not useful surrogates to study SARS-CoV-2 infection in farmed animals.

Four studies under preclinical and clinical conditions were performed to evaluate the efficacy of a new trivalent vaccine against Porcine circovirus 2 (PCV-2) infection. The product contained inactivated PCV-1/PCV-2a (cPCV-2a) and PCV-1/PCV-2b (cPCV-2b) chimeras, plus M. hyopneumoniae inactivated cell-free antigens, which was administered to piglets in a two-dose regime at 3 days of age and 3 weeks later. The overall results of preclinical and clinical studies show a significant reduction in PCV-2 viraemia and faecal excretion, and lower histopathological lymphoid lesions and PCV-2 immunohistochemistry scores in vaccinated pigs when compared to non-vaccinated ones. Furthermore, in field trial A, a statistically significant reduction in the incidence of PCV-2-subclinical infection, an increase in body weight from 16 weeks of age to slaughterhouse and an average daily weight gain over the whole period (from 3 days of age to slaughterhouse) was detected in the vaccinated group when compared to the non-vaccinated one. Circulation of PCV-2a in field trial A, and PCV-2b plus PCV-2d in field trial B was confirmed by virus sequencing. In conclusion, a double immunization with a cPCV-2a/cPCV-2b/M. hyopneumoniae vaccine was efficacious against PCV-2 infection by reducing the number of histopathological lymphoid lesions and PCV-2 detection in tissues, serum, and faeces, as well as reducing losses in productive parameters.

This study aimed to evaluate the efficacy of a new trivalent vaccine containing inactivated Porcine Circovirus 1-2a and 1-2b chimeras and a Mycoplasma hyopneumoniae bacterin administered to pigs around 3 weeks of age. This trivalent vaccine has already been proved as efficacious in a split-dose regimen but has not been tested in a single-dose scenario. For this purpose, a total of four studies including two pre-clinical and two clinical studies were performed. Globally, a significant reduction in PCV-2 viraemia and faecal excretion was detected in vaccinated pigs compared to non-vaccinated animals, as well as lower histopathological lymphoid lesion plus PCV-2 immunohistochemistry scorings, and incidence of PCV-2-subclinical infection. Moreover, in field trial B, a significant increase in body weight and in average daily weight gain were detected in vaccinated animals compared to the non-vaccinated ones. Circulation of PCV-2b in field trial A and PCV-2a plus PCV-2d in field trial B was confirmed by virus sequencing. Hence, the efficacy of this new trivalent vaccine against a natural PCV-2a, PCV-2b or PCV-2d challenge was demonstrated in terms of reduction of histopathological lymphoid lesions and PCV-2 detection in tissues, serum and faeces, as well as improvement of production parameters.