The hypothesis tested was that randomization of palm oil would increase its digestibility, especially that of its palmitic acid (C16:0) component, with subsequent changes in the fatty acid composition in body tissues. Broiler chickens were fed diets containing either native or randomized palm oil. Diets with either native or a 50/50 mix of native and hydrogenated sunflower oil were also fed. Randomization of palm oil raised the fraction of C16:0 at the sn-2 position of the glycerol molecule from 14 to 32%. Hydrogenation of sunflower oil reduced fat and total saturated fatty acid digestibility, whereas no change in digestibility of total unsaturated fatty acids was found. Randomization of palm oil raised the group mean apparent digestibility of C16:0 by 2.6 and 5.8% units during the starter and grower-finisher phase, respectively. On the basis of the observed digestibilities in the grower-finisher period, it was calculated that the digestibility for C16:0 at the sn-2 and sn-1,3 position was 90 and 51%, respectively. The feeding of randomized instead of native palm oil significantly raised the palmitic acid content of breast meat and abdominal fat and lowered the ratio of unsaturated to saturated fatty acids. It is concluded that randomized palm oil may be used as vegetable oil in broiler nutrition with positive effect on saturated fatty acid digestibility when compared with native palm oil and positive effect on firmness of meat when compared with vegetable oils rich in unsaturated fatty acids.

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A hypothesis is proposed how Low Frequency Electromagnetic Field (LF EMF) exposure can stimulate an immune response, based on recent insights in immunology. We hypothesize that the Immunent EMF treatment induces mild stress to cells, which then produce cytokines that function as alarms or so called danger signals for the immune system. In this way EMF treatment takes the place of multiplying pathogens, and the damage these cause, in the triggering of an immune response. In a first series of experiments in vitro common carp head kidney-derived phagocytes were used to determine ROS production as a measure for immune activation. Exposure to LF EMF signals (200-5,000 Hz) at 5 lT or 1.5 mT led to 42 or 33% increase in immune activity, respectively, compared to negative control values. EMF could also additionally stimulate chemically pre-stimulated samples up to 18% (5 lT) or 22% (1.5 mT). Significance of increase in ROS production in the total series was: p < 0.0001. In a second series of experiments in vitro commercial goldfish were used. Groups of fish were housed under equal conditions in at least four control tanks and 8-16 EMF-exposed tanks. Exposure was done with a predominantly vertical field at field strengths (rms) between 0.15 and 50 lT. Without treatment mortality was about 50% after 18 days, while the treatment at 5 lT reduced it to 20% on average. At field strengths 0.15, 0.5, 1.5, 5, 15 and 50 lT an equally strong effect was found. Reducing the field strength to 0.05, 0.06, 0.01 and 0.003 lT showed a gradually decreasing effect, which only at 0.003 lT is no longer statistically significant. Finally, in vitro experiments were done with 560 commercial broiler chickens exposed to infection pressure from coccidiosis. EMF exposure at 6.5 lT reduced intestinal lesions by 40% and improved feed conversion by 8%.