The lack of available vaccines against African swine fever virus (ASFV) means that the evaluation of new immunization strategies is required. Here we show that fusion of the extracellular domain of the ASFV Hemagglutinin (sHA) to p54 and p30, two immunodominant structural viral antigens, exponentially improved both the humoral and the cellular responses induced in pigs after DNA immunization. However, immunization with the resulting plasmid (pCMV-sHAPQ) did not confer protection against lethal challenge with the virulent E75 ASFV-strain. Due to the fact that CD8+ T-cell responses are emerging as key components for ASFV protection, we designed a new plasmid construct, pCMV-UbsHAPQ, encoding the three viral determinants above mentioned (sHA, p54 and p30) fused to ubiquitin, aiming to improve Class I antigen presentation and to enhance the CTL responses induced. As expected, immunization with pCMV-UbsHAPQ induced specific T-cell responses in the absence of antibodies and, more important, protected a proportion of immunized-pigs from lethal challenge with ASFV. In contrast with control pigs, survivor animals showed a peak of CD8+ T-cells at day 3 post-infection, coinciding with the absence of viremia at this time point. Finally, an in silico prediction of CTL peptides has allowed the identification of two SLA I-restricted 9-mer peptides within the hemagglutinin of the virus, capable of in vitro stimulating the specific secretion of IFNγ when using PBMCs from survivor pigs. Our results confirm the relevance of T-cell responses in protection against ASF and open new expectations for the future development of more efficient recombinant vaccines against this disease.

In endurance athletes who are native to moderate altitude, tHb and BV were synergistically influenced by training and by altitude exposure, which is probably one important reason for their high performance.

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14Torque teno virus (TTV) is a non-enveloped, single stranded DNA (ssDNA) 15 virus infecting human and non-primate species. Two genogroups of TTV (TTV1 and 16 TTV2) have been described in swine so far. In the present study, TTV1 and TTV2 17 prevalences in serum, and nasal as well as rectal swabs of 55 randomly selected piglets 18 from seven Spanish multi-site farms, were monitored from 1 to 15 weeks of age. Also, 19 blood from their dams (n=41) were taken at 1 week post-farrowing. Samples were 20 tested by means of two TTV genogroup specific PCRs. Although prevalence of TTV1 21 and TTV2 in sows was relatively high (54% and 32%, respectively), it was not directly 22 associated to their prevalence in the offspring. Percentage of viremic pigs for both TTV 23 genogroups followed similar dynamics, increasing progressively over time, with the 24 highest rate of detection at 11 weeks of age for TTV1 and at 15 weeks for TTV2. Forty-25 two (76%) and 33 (60%) of the 55 studied pigs were TTV1 and TTV2 PCR positive in 26 serum, respectively, in more than one sampling time. TTV1 and TTV2 viremia lasted in 27 a number of animals up to 15 and 8 weeks, respectively. Co-infection with both TTV 28 genogroups in serum was detected at all sampling points, but at 1 week of age. On the 29 contrary, there were animals PCR negative to both genogroups in serum at all sampling 30 times but at 15 weeks of age. During the study period, TTV1 and TTV2 nasal shedding 31 increased also over time and faecal excretion was intermittent and of low percentage 32 (<20%). In conclusion, the present study describes for the first time the infection 33 dynamics of TTV1 and TTV2 as well as the nasal and faecal excretion throughout the 34 life of in pigs from conventional, multi-site farms. Moreover, results indicate that both 35 swine TTV genogroups are able to establish persistent infections in a number of pigs. 36