Center El Toruno
Center El Toruno
Garcia-Mesa S.,University of Granada |
Suarez M.D.,University of Almeria |
Rodriguez-Rua A.,Center El Toruno |
Cardenas S.,Center El Toruno |
Garcia-Gallego M.,University of Granada
Aquacultural Engineering | Year: 2014
To gain information concerning the optimal feeding conditions for meagre (Argyrosomus regius) culture at the juvenile stage (170. g initial wt), four experimental feeding regimes were tested in duplicate lots. All fish were fed with a similar total weekly ration but distributed in 7, 6, or 5 days per week in the morning (lots 7M, 6M, and 5M, respectively) or 5 days per week in the afternoon (lots 5A). Over the 45 and 90-day experiment, some biometric, productive, and metabolic parameters were determined. Growth rates were very similar in all lots, the highest being in 6M fish, which exhibited the best food utilization. No major differences were detected either in body morphometry or body composition. Differences in liver and muscle activities in certain enzymes involved in the intermediary metabolism appear to reflect the impact of the intermittent food deprivation in 5M and 5A fish. In general, the feeding regime based on weekly one-day food deprivation appeared to be favourable for fish and thus could be profitable for fish farming. © 2014 Elsevier B.V.
Labella A.,University of Malaga |
Manchado M.,Center el Toruno |
Alonso M.C.,University of Malaga |
Castro D.,University of Malaga |
And 2 more authors.
Journal of Applied Microbiology | Year: 2010
Aims: The aim of this study was to analyse the intraspecific variability of Photobacterium damselae ssp. damselae strains isolated from different cultured marine fish species using molecular typing methods. Methods and Results: Twenty P. damselae ssp. damselae strains isolated from marine fish species were used in this study. Phenotypic characterization of the strains was carried out using standard microbiological methods. Genetic characterization was conducted using three PCR-based methods [random amplified polymorphic DNA (RAPD), enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR) and repetitive extragenic palindromic-PCR (REP-PCR)]. Dice coefficient and the unweighted pair group method with average linkage were used for numerical analyses of banding patterns. At phenotypic level, the strains analysed showed seven different profiles, which could not be related to the host fish species, geographic area or outbreak of disease. Isolates were grouped into nine and eight clusters using the RAPD technique with primers 5 and 4, respectively. In both cases, the main cluster grouped 45% of strains. The techniques ERIC-PCR and REP-PCR were more discriminatory, both resulting in 14 different clusters, which grouped 15-20% of the isolates. Conclusions: In this study, the techniques tested are confirmed as good tools for molecular typing, because they allow discrimination between P. damselae ssp. damselae strains isolated within the same outbreak. In addition, ERIC-PCR and REP-PCR methods were more adequate for rapid typing of P. damselae ssp. damselae than RAPD, allowing the discrimination at strain level. Significance and Impact of the Study: The results, in agreement with previous studies, confirmed the high intraspecific variability among isolated P. damselae ssp. damselae strains at both phenotypic and genetic levels. This suggests the existence of different clonal lineages that coexist in the same geographic area, within a short period of time (2-3 years). The discrimination at strain level can be useful to study the traceability of infections. © 2009 The Society for Applied Microbiology.
Lopez-Jimena B.,University of Malaga |
Lopez-Jimena B.,Center El Toruno |
Garcia-Rosado E.,University of Malaga |
Infante C.,Center El Toruno |
And 5 more authors.
Journal of Fish Diseases | Year: 2010
A non-destructive procedure based on nested RT-PCR and dot-blot hybridization has been developed for the detection of asymptomatic IPNV-carrier fish. The pair of primers designed for RT-PCR amplified a 599-bp fragment of the pVP2 region within the polyprotein gene, resulting in the detection of IPNV genotype III.1. The use of a nested RT-PCR allowed the amplification of IPNV genotypes III.1 and I.2. In addition, a 191-bp probe was designed for hybridization studies used in combination with the nested RT-PCR. The application of the nested RT-PCR to analyse blood samples from asymptomatic redbanded seabream, Pagrus auriga, and common seabream, P. pagrus, specimens showed a 53.1% and 77.8% prevalence of IPNV-carriers, respectively. The combination of nested RT-PCR and dot-blot hybridization increased the detection rates up to 100% for redbanded seabream and 94.4% for common seabream. Therefore, the protocol described in this study is highly sensitive and specific for the detection of IPNV in asymptomatic carrier fish, and, in addition, the results demonstrate the carrier state in two newly cultured sparid species in southern Spain. © 2010 Blackwell Publishing Ltd.