Suchergebnisse

Small ruminant lentiviruses (SRLVs) are endemic in most areas of Europe, causing a chronic infection and a multisystemic disease affecting the udder, carpal joints, lungs, and central nervous system. Due to the lack of treatments and protective vaccination strategies, infection control is focused on the identification of infected animals through serological or molecular techniques. However, antigenic and genetic heterogeneity of SRLVs represent a clear drawback for diagnosis. Infected animals may present lower animal production parameters such as birth weight or milk production and quality, depending on productive systems considered and, likely, to the diagnostic method applied. In this study, four sheep flocks dedicated to dairy or meat production were evaluated using three different ELISA and two PCR strategies to classify animal population according to SRLV infection status. Productive parameters were recorded along one whole lactation or reproductive period and compared between positive and negative animals. SRLV was present in 19% of the total population, being unequally distributed in the different flocks. Less than half of the infected animals were detected by a single diagnostic method, highlighting the importance of combining different diagnostic techniques. Statistical analysis employing animal classification using all the diagnostic methods associated lambing size, lamb weight at birth, and daily weight gain with SRLV infection status in meat flocks. Milk production, somatic cell count, fat, and protein content in the milk were associated with SRLV infection in dairy flocks, to a greater extent in the flock showing higher seroprevalence. A multi-platform SRLV diagnostic strategy was useful for ensuring correct animal classification, thus validating downstream studies investigating production traits. ; This research was funded by the Spanish Ministry of Science, Innovation and Universities, grant number RTI2018-096172-BC31, and by the Government of Navarra and European Union ERDF program, grant number PDR (210160006). LD and IE were funded by Universidad Pública de Navarra. RR was supported by the Spanish Ministry of Science and Innovation Ramón y Cajal contract. Authors acknowledge APC funding by the CSIC Open Access Publication Support Initiative through its Unit of Information Resources for Research (URICI). RD was a Ph.D. student funded by the Department of Innovation, Research and University of Aragón.

Aluminum (Al) hydroxide is an effective adjuvant used in sheep vaccines. However, Al-adjuvants have been implicated as potential contributors to a severe wasting syndrome in sheep—the so-called ovine autoimmune-inflammatory syndrome induced by adjuvants (ASIA syndrome). This work aimed to characterize the effects of the repetitive injection of Al-hydroxide containing products in lambs. Four flocks (Flocks 1–4; n = 21 each) kept under different conditions were studied. Three groups of seven lambs (Vaccine, Adjuvant-only, and Control) were established in each flock. Mild differences in average daily gain and fattening index were observed, indicating a reduced growth performance in Vaccine groups, likely related to short-term episodes of pyrexia and decreased daily intake. Clinical and hematological parameters remained within normal limits. Histology showed no significant differences between groups, although there was a tendency to present a higher frequency of hyperchromatic, shrunken neurons in the lumbar spinal cord in the Adjuvant-only group. Although Al-hydroxide was linked to granulomas at the injection site and behavioral changes in sheep, the results of the present experimental work indicate that injected Al-hydroxide is not enough to fully reproduce the wasting presentation of the ASIA syndrome. Other factors such as sex, breed, age, production system, diet or climate conditions could play a role. ; This work was funded by grants from the Spanish Ministry of Economy, Industry and Competitiveness (AGL2013-49137-C3-1-R and AGL2013-49137-C3-2-R), the Ministry of Science, Innovation and Universities (RTI2018-096172-B-C31 and RTI2018-096172-B-C33) and the Recognized Research Groups of Government of Aragón (A17_17R, Animal Health and Reproduction). RdM was a PhD student funded by the Department of Innovation, Research and University of Aragón. JA and ARL were PhD students funded by the Spanish Ministry of Science, Innovation and Universities (formerly Spanish Ministry of Education). IE was a PhD student funded by the Universidad Pública de Navarra.