Traylor S L, Cromwell G L, Lindemann M D
Department of Animal and Food Sciences, University of Kentucky, Lexington, 40546, USA.
J Anim Sci. 2005 Nov;83(11):2554-63. doi: 10.2527/2005.83112554x.
Meat and bone meal (MBM), when supplemented with tryptophan, is an excellent protein source for pigs. It is also a rich source of Ca and P, but some research has suggested that the bioavailability of P is variable. Three experiments were conducted to determine whether particle size, ash content, or processing pressure of MBM influences the bioavailability of P. Each experiment involved six replications of six treatments with individually penned pigs initially averaging 13 to 17 kg of BW. A low-P basal diet was fed with or without 0.1 or 0.2% added P (as-fed basis) from monosodium phosphate (MSP) or with three types of MBM added at levels that supplied 0.2% P (as-fed basis). The Ca level was 0.70%, and the lysine level was 0.95% in all diets. Pigs were allowed to consume their diets (meal form) on an ad libitum basis. At the end of the study, pigs were killed, and femurs and third and fourth metacarpals and metatarsals were removed for determination of breaking strength and ash content. Bone traits were regressed on added P intake for each P source, and slope-ratio procedures were used to estimate the bioavailability of P in MBM relative to that in MSP. In Exp. 1, a blended source of MBM ground to three particle sizes (amount that passed through 6-, 8-, or 12-mesh screens) was evaluated. In Exp. 2, low-ash MBM of porcine origin, high-ash MBM of bovine origin, and a 1:1 blend of the two sources were assessed. In Exp. 3, normally processed MBM was subjected to an additional 2.1 and 4.2 kg/cm2 of pressure for 20 min to determine whether excessive heat treatment would influence the bioavailability of P. Fineness of grind of MBM or processing pressure did not influence the relative bioavailability of P in this study; however, ash content of MBM affected P bioavailability. The relative availability of P in low-ash MBM of porcine origin (with composition typical of meat meal) was approximately 15 percentage units less than that in high-ash MBM of bovine origin. Overall, the bioavailability of P in MBM, relative to that in MSP, averaged 85%.
肉骨粉（MBM）在补充色氨酸后，是猪的优质蛋白质来源。它也是钙和磷的丰富来源，但一些研究表明磷的生物利用率存在差异。进行了三项试验，以确定肉骨粉的粒度、灰分含量或加工压力是否会影响磷的生物利用率。每项试验包括六个处理组，每组六头猪单独饲养，初始体重平均为13至17千克，共六个重复。饲喂低磷基础日粮，添加或不添加0.1%或0.2%的磷（以饲喂状态计），添加的磷来自磷酸一钠（MSP），或添加三种类型的肉骨粉，添加水平为提供0.2%的磷（以饲喂状态计）。所有日粮中的钙水平为0.70%，赖氨酸水平为0.95%。猪可自由采食日粮（粉料形式）。在研究结束时，处死猪，取出股骨、第三和第四掌骨及跖骨，测定其断裂强度和灰分含量。针对每种磷源，将骨特性与添加的磷摄入量进行回归分析，并采用斜率比法估计肉骨粉中磷相对于磷酸一钠中磷的生物利用率。在试验1中，评估了一种混合的肉骨粉来源，将其研磨至三种粒度（通过6目、8目或12目筛网的量）。在试验2中，评估了猪源低灰分肉骨粉、牛源高灰分肉骨粉以及两者1:1的混合物。在试验3中，对正常加工的肉骨粉施加额外的2.1和4.2千克/平方厘米压力20分钟，以确定过度热处理是否会影响磷的生物利用率。在本研究中，肉骨粉的研磨细度或加工压力并未影响磷的相对生物利用率；然而，肉骨粉的灰分含量影响磷的生物利用率。猪源低灰分肉骨粉（具有肉粉的典型成分）中磷的相对利用率比牛源高灰分肉骨粉低约15个百分点。总体而言，肉骨粉中磷相对于磷酸一钠中磷的生物利用率平均为85%。
