The concentrations of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and coplanar-polychlorinated biphenyls (Co-PCBs) in muscle, back fat, liver and whole blood of castrated male pig (Landrace) were determined at 1, 3, 4.5 and 6 month of age to examine the transfer and the accumulation of dietary dioxin in fattening pig. Also the concentrations in four diets, replacer, starter, grower and finisher, fed to experimental animal were measured. Concentrations of each isomer in the three components were measured through capillary column gas chromatography-high resolution mass spectrograph system. They were multiplied by individual toxic equivalency factors (TEF), and each value was accumulated. Then toxic equivalency quantities (TEQ) were driven from them.
The concentrations of the dioxins (total TEQ of PCDDs, PCDFs and Co-PCBs) and the composition of the three components (PCDDs, PCDFs and Co-PCBs) in the four diets were different. The dioxin concentrations in replacer and starter were higher than that of grower and finisher. The finisher showed relatively low concentration, below 2fg-TEQ/g. The concentration of the dioxins in whole blood was detected at 1 and 6 month of age. Co-PCBs was observed. The concentrations of the dioxins in muscle declined as experiment animal grew. The concentration at 6 month of age was 57fg-TEQ/g. The same tendency was observed in back fat, but was not observed in liver. The concentration in the liver reduced less. And the composition of three components in the liver showed almost same pattern from 1 to 6 month of age. The dioxins concentration in the diets reflected in the concentrations of the muscle and the back fat. It is suggested that most of dietary dioxins were accumulated in the liver and were excreted hardly, although the dioxins in muscle was transferred easily to other tissues.

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In order to evaluate the application of tea grounds as bulking agents, the composted performance of swine feces mixed with dry tea grounds was investigated, and the effect of tea grounds was examined for material temperature, bulk weight, ammonia emission, and ingredients. Three sets of compost were mixed with a variety of bulking agents; tea grounds only (TG), sawdust only (S), tea grounds and sawdust mixed at a ratio of 1:1 (M). An admixture of swine feces and bulking agents was composted in an experimental composting apparatus for 28 days. The temperatures of M and S did not vary, although that of Tea grounds increased later than that of the other sets. Material temperatures of TG, M, and S were amounted to 7668.7, 8135.0 and 8024.6 C, respectively. Initial bulk weights were about 0.57kg/l. As time passed, bulk weights of M and S decreased to about 0.30kg/l, while that of TG remained at more than 0.40kg/l. Data indicate that with the addition of tea grounds only, swine feces fermentation decreased because of low ventilation inside compost of higher bulk weight, and that with the addition of both TG and S, fermentation did not decrease at all. Ammonia emission of TG decreased with the deterioration of fermentation under lower ventilation conditions because of the absence of deodorizing agents in tea grounds. There was no significant difference in the decomposition rate of organic matter during composting. The addition of tea grounds increased manure ingredients such as nitrogen, phosphate, and potash in the compost. Tea grounds did not interfere with Komatsuna seed germination tests. These results suggested that it is possible to make swine composts using tea grounds as bulk agents by supplementary mixing sawdust, and that this compost, which is rich in manure ingredients, does not pose a problem for crops.

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The aim of the present study was to develop an objective method for evaluating semen characteristics. Using various boar semen samples of different sperm concentrations, and samples stored at 15°C in liquid state, we compared the results of the rezasurin reduction test and sperm concentration, and sperm motility. Semen was collected from 14 boars. The seminal plasma was removed, and diluted with Modena to obtain 3×10⁸ sperm cells per ml. The rezasurin reduction test was performed as follows. One ml of a semen sample was added to 25μl of 2mM resazurin solution and mixed. The samples were cultured at 38°C for 1 hour, and then measured by spectrophotometer. In experiment-I, resazurin and resorufin solutions were scanned, respectively, to examine the peak absorbance at specific wavelengths by spectrophotometer. In experiment-II, we measured the relative absorbance of different sperm concentration samples. In experiment-III, we compared sperm motility and the relative absorbance of semen stored at 15°C. In experiment-I, the resazurin solution and the resorufin solution peaked at 600nm and 570nm, respectively. Based on the results of experiment-I, in experiment-II and-III, absorbance of the samples was measured at 570nm and 600nm. In experiment-II, the absorbance of samples measured at 600nm (resazurin) decreased as sperm concentration increased, whereas the absorbance of samples measured at 570nm (resorufin) increased as sperm concentration increased. In experiment-III, sperm motility decreased as semen storage periods increased, the absorbance measured at 570nm (resorufin) also decreased, whereas the absorbance of samples measured at 600nm (resazurin) decreased as storage periods increased. In conclusion, the resazurin reduction test used in the present study reflected the sperm metabolic state, concentration and motility. Therefore, the resazurin reduction test may be useful for objectively evaluating boar semen characteristics.

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