E-Learning Impact on Veterinary Medical Student's Mental Health during the COVID-19 Pandemic.

Veterinary medical students are known to have significant levels of mental illness. The COVID-19 pandemic and the shift to online learning have brought increased psychological stress. We used a web-based survey to ask 415 veterinary medical students from Portugal about the impact of the pandemic and online learning on their anxiety levels. Results were analyzed using logistic regressions and Spearman's correlation. Results indicated that 15.4% had no symptoms of anxiety, 39.5% experienced mild anxiety, 21.4% had moderate anxiety, and 23.6% experienced severe anxiety. Having difficulty sleeping, the stress associated with confinement, and family conflicts were risk factors for anxiety, while being male was found to be protective. Most veterinary medical students (77%) were satisfied with online learning. The university's adaptation to online teaching and time spent participating in online classes were significantly associated with anxiety. Due to the known fragility of veterinary medical students' mental health, this group should be monitored and supported closely during life-disrupting events such as public health emergencies.

Gene-culture coevolution between cattle milk protein genes and human lactase genes.

Milk from domestic cows has been a valuable food source for over 8,000 years, especially in lactose-tolerant human societies that exploit dairy breeds. We studied geographic patterns of variation in genes encoding the six most important milk proteins in 70 native European cattle breeds. We found substantial geographic coincidence between high diversity in cattle milk genes, locations of the European Neolithic cattle farming sites (>5,000 years ago) and present-day lactose tolerance in Europeans. This suggests a gene-culture coevolution between cattle and humans.

Immunization with a cocktail of antigens fused with OprI reduces Neospora caninum vertical transmission and postnatal mortality in mice.

OprI is an outer membrane lipoprotein from Pseudomonas aeruginosa, and when fused to a recombinant antigen, will exert adjuvant properties by engaging Toll-like receptor 2, leading to dendritic cell activation. Previous studies have shown that the Neospora caninum (Nc) antigens NcPDI, NcROP2 and NcROP40 are implicated in host cell interactions and are promising vaccine candidates. In two independent experiments, the efficacy of a polyvalent vaccine formulation composed of OprI-NcPDI, OprI-NcROP2 and OprI-NcROP40 (collectively named O-Ags) was assessed in non-pregnant and pregnant Balb/c mouse models challenged with tachyzoites of the high-virulence isolate Nc-Spain7. Parameters that were investigated were clinical signs, fertility, parasite burden in adult mice, humoral and cellular immune responses at different time-points prior to and after challenge infection, vertical transmission and post-natal survival of offspring mice, all to explore potential correlations with efficacy. Vaccination of mice with O-Ags induced a mixed Th1/Th2 immune response in adult mice and led to significantly increased protection against cerebral infection. Vaccination with O-Ags also resulted in reduced vertical transmission, and postnatal disease in offspring was significantly inhibited at a rate not observed in mice infected with a high-virulence isolate to date. However, O-Ags mixed with TLR ligands targeting TLR3 and TLR7, which are known to induce clear Th1-biased responses, or vaccination with OprI fused to the non-N. caninum antigen ovalbumin (OprI-OVA) did not confer protection.