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In the present study, the effect of different levels of magnetized water on the biochemical parameters of rainbow trout was investigated. 120 rainbow trout with mean weight (150±7 gr) were introduced to 12 tanks (500 L). Magnetizers in different intensities including 1500, 2500 and 3500 Gauss (3 replicates per treatment) were installed at the entry of every tank. Experimental period was eight weeks. The blood sampling was done at the beginning and end of the study to evaluate the biochemical blood parameters like Glucose, Lysozyme, total protein, Cortisol, aspartate aminotransferase (AST), alanine aminotransferase (ALT) and alkaline phosphatase (ALP). The results showed that the magnetized water had a significant effect on the biochemical parameters of the rainbow trout blood (P˂0.05). Totally, the liver enzymes (ALT, AST and ALP) decreased significantly (P˂0.05) with increasing of the magnetic intensity compared to the control treatment and in the case of lysozyme and total protein significantly increased (P˂0.05). The effect of magnetized water on stress-related parameters did not follow a specific pattern, however, the amount of glucose and cortisol in 2500- gauss treatment was 55.50±0.86 mg/dl and 11.65±0.08 ng/ml, respectively in which was decreased significantly (P˂0.05). In conclusion, some blood parameters of rainbow trout improved using different intensities of the magnetized water up to 2500 gauss.

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This study was conducted with two consequential experiments to investigate the effect of magnetized water on in-vitro limestone solubility and eggshell breaking strength in laying hens. The first experiment was conducted to investigate the effect of magnetized water and particle size on in-vitro limestone solubility. Three particle sizes including small particles, less than 0.125 mm; large particles, 2-4 mm and normal mix, 0.045-4.00 mm were tested. Magnetized water was generated by magnetizer of 0.65 Tesla magnetic fields. Scanning Electron Microscopy images (SEMi) were used to study the morphology of limestone crystals after dissolution in magnetized and tap water. Limestone solubility was measured by 0.2N HCl solution. The second in- vivo experiment was conducted to study the effect of magnetized water and dietary calcium on breaking strength of eggshell. Three dietary levels of calcium and phosphorus (normal, 10 and 20% reduced Ca and available P.) and two types of water (tap water and magnetized water) were used in Hy-line laying hens at 32 weeks of age. Breaking strength of the normal (safe and sound) eggs was measured with an Instron testing machine. The solubility of large limestone particles was less than those of small particles. Magnetically treated water did not change in-vitro limestone solubility but changed the morphology of limestone crystals. Precipitated limestone crystals in magnetized water tended to be larger and more uniform in size than those in tap water. Reducing dietary levels of Ca and P had no significant effect on egg breaking strength at 36 weeks of age. Magnetized water was able to numerically increase strength of the eggs. Therefore, based on the SEMi and the observed changes in crystalline structure of dissolved (exposed to water) precipitated limestone and observed changes in breaking strength of the eggs, it is hypothesized that magnetized water may have the potential to change the limestone availability and consequently egg strength in laying hens.