Effects of structure and xylanase treatment of brewers’ spent grain on performance and nutrient availability in broiler chickens

1.?A factorial (2 × 3) feeding trial was set up to investigate the effects of coarse or finely ground brewers’ spent grain (BSG) and xylanase treatment, either with no xylanase, top-dressed with xylanase or pre-treated with xylanase.

2.?The experimental diets shared the same basal formulation and were fed to male broiler chickens (Ross 308) housed in individual cages from 12 to 29 d of age.

3.?Xylanase pre-treatment reduced the dietary concentration of arabinoxylan by 15–30%. Pellet durability increased when BSG was ground.

4.?Feed utilisation was significantly higher (6%) when the birds were given coarse BSG rather than ground BSG, whereas there was no significant effect of enzyme treatment. Apparent metabolisable energy was unaffected by the dietary treatments.

5.?The overall starch digestibility was high (99%), with no dietary differences, whereas ileal protein digestibility was low (57%). Xylanase top-dressing tended to improve ileal protein digestibility but, in general, xylanase treatment had no major effect on overall performance in male broilers given diets with BSG.     

DEVELOPMENT OF AN AUTOMATED 12-8 BIT CONVERSION ALGORITHM FOR DISPLAYING AND ARCHIVING SCANNED RADIOGRAPHS

The lossless capture of the entire range of optical densities encountered in a radiograph can require up to 4000 individual shades of gray. Most inexpensive computer displays, and most grayscale image formats contain only 256 gray shades. To use these systems, a look up table must be generated to display the scanned image, which maps the approximately 4000 gray shades in the digitized radiograph to the 256 gray shades on the monitor. However, if this conversion is inappropriately performed, much of the information contained in the original image could be lost. This study was undertaken to develop an histogram equalization algorithm that would automatically convert the 4000 gray shade digitized radiograph into a 256 gray shade image file, without perceptable loss of diagnostic information or image quality.     

小麦与褐斑病菌之间的分子互作──Ⅱ．受病原菌诱导的寄主抗性蛋白的研究

采用ＳＤＳ－聚丙烯酰胺凝胶电泳及双向电泳技术对小麦抗、感品系在接种褐斑病菌（Ｐｔｒ）８６－１２４小种后２４，４８，７２ｈ叶片细胞间洗脱液的蛋白质进行了系统的动态研究。结果表明，寄主植物在受到病原物侵染后，２２种病原相关蛋白（ＰＲ）被诱导合成，接种后４８ｈ，ＰＲ蛋白的表达量达最大值，７２ｈ后相应减少。其中２０种组分在抗、感品系间的表达动态没有差异。Ｗｅｓｔｅｒｎ杂交分析证明，其中有７种为β－１，３－葡聚糖酶，４种为几丁酶，１种为ＰＲ－１蛋白，属非特异性抗性反应。研究还发现ｐＩ５．２、２２ｋｄ和ｐＩ６．６、１９ｋｄ的两种蛋白仅在感病品系内被诱导合成，与特异抗性反应有关。从凝胶中回收了这两种组分，并完成其氨基酸序列分析。     

小麦与褐斑病菌之间的分子互作──Ⅰ．受病原菌诱导的寄主PR基因的表达

采用Ｎｏｒｔｈｅｒｎ杂交技术，对小麦抗、感品系在接种褐斑病菌（ｐｔｒ）８６－１２４小种后８，１６，２４，３２，４０，４８，５６，６４，７２小时叶片病原相关蛋白（ＰＲ）基因在ｍＲＮＡ水平上的表达动态进行了研究。结果表明，小麦受到病原菌的侵染后，β－１，３－葡聚糖酶，几丁酶，苯丙氨酸解氨酶等病原相关蛋白基因在抗、感品系内均被诱导表达，表现了一种非特异性的抗性反应。并且，以上３个基因的诱导表达具有大体相似的动态规律。β－１，３－葡聚糖酶（ＰＲ－２）基因在接种病原菌ｐｔｒ后１６小时开始表达，４８小时后表达量达高峰，６４小时后表达减弱；几丁酶（ＰＲ－３）基因在接种后８小时开始表达，４８小时后达最大值，７２小时后表达量下降；苯丙氨酸解氨酶（ＰＡＬ）基因于接种后８小时被诱导表达，４８小时后表达进入盛期，６４小时后开始下降，但直至７２小时后仍维持一定水平，这种趋势较病程的发展一般提前１６小时左右。