Anthropogenic CO2 and ocean acidification in Argentine Basin Water Masses over almost five decades of observations.

The chemical conditions of the Argentine Basin (western South Atlantic Ocean) water masses are evaluated with measurements from eleven hydrographic cruises to detect and quantify anthropogenic and natural stressors in the ocean carbon system. The database covers almost half-century (1972-2019), a time-span where the mean annual atmospheric carbon dioxide concentration (CO2atm) increased from 325 to 408 ppm of volume (ppm). This increase of atmospheric CO2 (83 ppm, the 64% of the total anthropogenic signal in the atmosphere) leads to an increase in anthropogenic carbon (Cant) across all the water column and the consequent ocean acidification: a decrease in excess carbonate that is unequivocal in the upper (South Atlantic Central Water, SACW) and intermediate water masses (Sub Antarctic Mode Water, SAMW and Antarctic Intermediate Water, AAIW). For each additional ppm in CO2atm the water masses SACW, SAMW and AAIW lose excess carbonate at a rate of 0.39 ± 0.04, 0.47 ± 0.05 and 0.23 ± 0.03 µmol·kg-1·ppm-1 respectively. Modal and intermediate water masses in the Argentine Basin are very sensitive to carbon increases due low buffering capacity. The large rate of AAIW acidification is the synergic effect of carbon uptake combined with deoxygenation and increased remineralization of organic matter. If CO2 emissions follows the path of business-as-usual emissions (SSP 5.85), SACW would become undersaturated with respect to aragonite at the end of the century. The undersaturation in AAIW is virtually unavoidable.

Retrospective detection of Porcine circovirus 3 (PCV-3) in pig serum samples from Spain.

Porcine circovirus 3 (PCV-3) is an emerging circovirus species that has recently been reported in different countries around the world, suggesting a widespread circulation. In this study, sera samples originating from 654 pigs of different production phases and clinical/pathological conditions, submitted for diagnostic purposes between 1996 and 2017, were randomly selected. Detection of PCV-3 genome in such samples was attempted with a previously described PCR method, and the partial genome sequence was obtained from selected PCV-3-positive samples from different years. Compiled data confirmed that PCV-3 has been circulating in the Spanish pig population since 1996. The overall frequency of PCV-3 PCR-positive samples in the study period was 11.47% (75 of 654). Phylogenetic analysis of twelve PCV-3 partial sequences obtained showed a high nucleotide identity with the already known PCV-3 sequences, with minor variations among years. No significant correlation was found between the detection of PCV-3 and any production phase nor clinical/pathological condition. These results confirm PCV-3 circulation at least since 1996 in the Spanish pig population with a low/moderate frequency. Although the information obtained was limited, PCV-3 did not appear to be linked to any specific pathological condition or age group.