The objective was to evaluate industrial and research slaughter methods for Atlantic salmon (Salmo salar), gilt-head seabream (Sparus auratus) and eel (Anguilla anguilla) with respect to welfare and quality. As a general term of reference, an optimal slaughter method should render fish unconscious until death without avoidable excitement, pain or suffering prior to killing. For Atlantic salmon, commercial slaughter methods (carbon dioxide stunning followed by gill cutting, and gill cutting alone) are not in conformity with the general term of reference, as the fish are not rendered unconscious immediately and possibly experience stress. Evaluation of automated percussive stunning remained unconclusive. More research should enable us to ascertain whether loss of consciousness is instantaneous. Electrical stunning can be humane if applied properly. However, because flesh of electrostunned fish was characterized by occasional bloodspots, optimization of the electrical parameters is required. Prototypes for percussive and electrical stunning of salmon have been recently developed. This implies that humane slaughter of salmon is feasible for industry. For gilt-head seabream, neither aphyxia in air nor transfer of the fish to an ice slurry were considered to be humane: the methods did not induce immediate brain dysfunction and vigorous attempts to escape occurred. Percussive and electrical stunning can be in conformity with the general term of reference. However, conditions for stunning whole batches of seabream have not been established. Quality of the fish slaughtered by percussive stunning was similar to that obtained by the industrial method, i.e. immersion in an ice slurry. Further work is required to establish optimal stunning conditions and to develop prototypes. For eel, desliming in a salt-bath followed by evisceration, electrical stunning performed under the conditions prescribed by the German legislation, and live chilling and freezing were not considered to be humane. In contrast, it was established that a 10±20 kg batch of eels in fresh water could be rendered unconscious immediately and until death by applying electricity in combination with nitrogen gas. The conditions used were 0.64 A dm À2 for 1 s, followed by 0.17 A dm À2 combined with nitrogen flushing for 5 min. A preliminary assessment of flesh quality suggests that it may be improved by application of the latter method, compared with the salt bath. The results clearly indicated that humane slaughter of eels is possible in practice.

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Sensory assessment is one of the principal methods of measuring fish quality. One of the most interesting sensory methods at the moment is the quality index method (QIM). The QIM provides weighted evaluation of the key parameters in deterioration of individual species, assigning demerit points according to the importance of the parameter. This paper describes the development of a QIM for gilthead seabream (Sparus aurata). As result of this study, a QIM is proposed for this species . The appearance of skin and slime, flesh elasticity, odor of the fish, clarity and shape of the eyes, and color and odor of the gills are the parameters included which gave a total of 15 demerit points. The index scored lower when the fish was washed.

Natural actomyosin was extracted from frozen minced cod muscle stored for up to 62 weeks at −20 °C with 0.6 M NaCl, and the insoluble aggregates, when formed, were solubilized successively with 2% sodium dodecyl sulfate (SDS) and 2% SDS + 5% β-mercaptoethanol (ME) solutions, giving extracted fractions S1 (NaCl), S2 (SDS), and S3 (ME + SDS), precipitates insoluble in 0.6 M NaCl (P1) and 2% SDS (P2), and a precipitate not soluble in any of the agents used (P3). SDS polyacrylamide gel electrophoresis (SDS-PAGE) of fraction S1 showed that the proportion of the major proteins changed during frozen storage. Size exclusion chromatography showed a decrease in the peak containing myosin heavy chain (MHC) and actin (Ac). Transmission electron microscopy (TEM) of S1 showed at the outset a filamentous morphology associated with globules interconnected crosswise. As storage progressed, the number and size of aggregates increased. In fractions S2 and S3, the major proteins detected by SDS-PAGE were MHC and Ac. TEM showed a greater abundance of ring-shaped structures than in S1. TEM of the insoluble fractions showed a sarcomere-like structure, more pronounced the milder the solubilizing treatment and the longer the storage time. Keywords: Aggregation; frozen storage; actomyosin; cod; mince; Gadus morhua; microstructure

Monoconidial cultures of 15 isolates of Trichoderma harzianum were characterized on the basis of 82 morphological, physiological, and biochemical features and 99 isoenzyme bands from seven enzyme systems. The results were subjected to numerical analysis which revealed four distinct groups. Representative sequences of the internal transcribed spacer 1 (ITS 1)-ITS 2 region in the ribosomal DNA gene cluster were compared between groups confirming this distribution. The utility of the groupings generated from the morphological, physiological, and biochemical data was assessed by including an additional environmental isolate in the electrophoretic analysis. The in vitro antibiotic activity of the T. harzianum isolates was assayed against 10 isolates of five different soilborne fungal plant pathogens: Aphanomyces cochlioides, Rhizoctonia solani, Phoma betae, Acremonium cucurbitacearum, and Fusarium oxysporum f. sp. radicis lycopersici. Similarities between levels and specificities of biological activity and the numerical characterization groupings are both discussed in relation to antagonist-specific populations in known and potential biocontrol species.