Suchergebnisse

Enteromyxum scophthalmi, an intestinal myxozoan parasite, is the causative agent of a threatening disease for turbot (Scophthalmus maximus, L.) aquaculture. The colonisation of the digestive tract by this parasite leads to a cachectic syndrome associated with high morbidity and mortality rates. This myxosporidiosis has a long pre-patent period and the first detectable clinical and histopathological changes are subtle. The pathogenic mechanisms acting in the early stages of infection are still far from being fully understood. Further information on the host–parasite interaction is needed to assist in finding efficient preventive and therapeutic measures. Here, a RNA-seq-based transcriptome analysis of head kidney, spleen and pyloric caeca from experimentally-infected and control turbot was performed. Only infected fish with early signs of infection, determined by histopathology and immunohistochemical detection of E. scophthalmi, were selected. The RNA-seq analysis revealed, as expected, less intense transcriptomic changes than those previously found during later stages of the disease. Several genes involved in IFN-related pathways were up-regulated in the three organs, suggesting that the IFN-mediated immune response plays a main role in this phase of the disease. Interestingly, an opposite expression pattern had been found in a previous study on severely infected turbot. In addition, possible strategies for immune system evasion were suggested by the down-regulation of different genes encoding complement components and acute phase proteins. At the site of infection (pyloric caeca), modulation of genes related to different structural proteins was detected and the expression profile indicated the inhibition of cell proliferation and differentiation. These transcriptomic changes provide indications regarding the mechanisms of parasite attachment to and invasion of the host. The current results contribute to a better knowledge of the events that characterise the early stages of turbot enteromyxosis and provide valuable information to identify molecular markers for early detection and control of this important parasitosis. ; This study was funded by the Spanish Ministry of Economy and Competitiveness (AGL 2009-13282-C02-01 and -02; AGL2015-67039-C3-1-R and AGL2015-67039-C3-3-R), the European Regional Development Fund (ERDF, European Union) and Xunta de Galicia (Spain) local government (GRC2014/010 and GPC2015/34). Diego Robledo was supported by a FPU fellowship funded by the Spanish Ministry of Education, Culture and Sport. Paolo Ronza was supported by a grant from the scientific network "INMUNOGENOM", funded by Xunta de Galicia (REDES GI-1251). ; Peer Reviewed

The goal of this study was to compare the growth performance of growing/finishing pigs housed in a hoop barn system and in traditional confinement. A total of twenty Bísaro breed pigs, with 98.6±5.71 days of age, and 25.4±4.87 kg of BW were used (beginning of experiment). The pigs were equally distributed in two groups: Gr1 - hoop barn (3.0 m2/pig) with outdoor access (200 m2/pig); and Gr2 - traditional confinement with straw bedding (1.8 m2/pig). Both groups were fed with the same diet. During the next 98 days' period (growing phase) and until pigs reached approximately 80 kg LW, the animals were fed with a concentrate diet. In the finishing phase consisting of a final 70 days period until slaughter, the animals reached between 110-120 kg LW and were fed with concentrate and cornflour. The feed intake per group was registered daily and growth performances were collected every two weeks. During the growing phase no differences (P > 0.05) were observed in the average daily gain (ADG) between Gr1 (0.546±0.10 kg/day) and Gr2 (0.563±0.05 kg/day). However, a higher variability was observed in hoop barn group (CV of 18.1% vs. 8.8% in confinement). Similar results were observed during the finishing phase with ADG of 0.535±0.09 kg for Gr1 and 0.505±0.07 kg for Gr2 (P > 0.05). In both growing and finishing phases, the feed conversion rates (FCR) were 3.11 on the Gr1 versus 3.12 kg/kg on the Gr2, and 3.44 in Gr1 versus 3.53 in Gr2, respectively. Despite the different housing systems, ADG and FCR per period were identical in both systems. To the consumer's point of view, the positive aspects of the hoop barn system, such as the use of uncultivated land, product image and pig welfare, are sustainably attractive and therefore could be further reflected in the market. ; This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 634476 (Project acronym: TREASURE). The content of this paper reflects only the author's view and the European Union Agency is not responsible for any use that may be made of the information it contains. ; info:eu-repo/semantics/publishedVersion