Aquaculture is the fastest growing animal production sector. However, the production of marine fish is still hampered by the high mortality rate in the first few weeks after hatching. Mortality in larvae is often caused by microbial infections. Today, the incorporation of immunostimulants into microparticles provides us new tools to enhance disease resistance in marine larviculture. In this study, we prepared alginate microparticles loaded with the model antigen fluorescein isothiocyanate conjugated-bovine serum albumin. Optimum concentrations of alginate and CaCl, the correct alginate viscosity and the appropriate preparatory conditions led to the creation of desirable microparticles with the correct size for oral feeding in gnotobiotic European sea bass larvae. The prepared alginate microparticles were stable in sea water and were successfully ingested by gnotobiotic sea bass larvae at day after hatching 7 without causing any negative effects. Results suggest the suitability of this drug delivery system for targeting the innate immune system of fish larvae in order to enhance disease resistance and thus reduce mortality in larviculture.

The total volatile basic nitrogen fraction (TVB-N) is often used as a quality parameter in the fish industry to assess spoilage. This parameter often leads to discussions between producers and retailers when it comes to defining clear limits of acceptability for modified atmosphere (MA) packed fish and fishery products. Suggested product limits (mg N/100 g fish) do not always correlate with the presence of off-odors. Gray shrimp are an economic valuable, very perishable niche product, where the TVB-N fraction plays an important role considering its shelf life. This research focuses on the effect of a shrimp matrix and its pH on the volatilization of these formed bases, revealing the relationship between concentrations in the fishery product and the concentrations of these bases present in the headspace of the packed product. Especially, the pH of the product, which is lowered when fishery products are packed under a carbon dioxide enriched atmosphere, appeared to have an immense effect on the volatilization of these bases. The effect of the fish matrix itself is established by means of calculated equilibration constants (dimensionless) being 2.13 Â 10 -4 ( 0.38 Â 10 -4 for trimethylamine, 6.34 Â 10 -5 ( 1.71 Â 10 -5 for dimethylamine, and 2.58 Â 10 -5 ( 0.49 Â 10 -5 for ammonia. Comparison of these constants with the equilibration constants of an aqueous solution indicated the retention of these bases in the product. This article provides not only the important insights for the interpretation of TVB-N values in modified atmosphere packaged gray shrimp but also the methodology to extend these findings to other fish and fishery products.

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Internet of Animal Health Things is an upcoming domain in both professional and domestic fields related to animal welfare monitoring including dairy cows, racehorses and domestic dogs. Wireless Body Area Networks represent a large allotment in the realization of these applications. Characterization of the path loss between on-body nodes in various surroundings is required when deploying such network. In this paper, the path loss between various on-body transmitting sensors and an on-body receiver is investigated at 2.45 GHz. Simulations using the Finite-Difference Time-Domain method are performed using a representative, homogeneous canine model on which two half-wavelength dipoles are placed at short distance from the body of the dog. Several combinations of transmitter and receiver locations and orientations are explored and for each transmitter location, the orientation and receiver location resulting in minimal path loss is determined. All path loss results are fitted to a log-normal path loss model with path loss exponent n ranging from 2.7 to 3.5. A link budget is composed with the wireless technologies ZigBee. The battery lifetime for several modules is determined. The ZigBee device XB24CAPIT-001 assures 237 days without recharging when using a battery capacity of 5000 mAh with an awake time period of 25%.