[NIRS method for determination of meat and bone meal content in ruminant concentrates]

Feed contaminated with MBM is commonly accepted as the main transmission carrier of bovine spongiform encephalopathy (BSE). To prevent BSE many countries have banned MBM as a feed ingredient. In the People's Republic of China, the ban was first applied to ruminant feed. In order to investigate the feasibility of near infrared diffuse reflectance spectroscopy method for rapidly quantitative determination of meat and bone meal content in ruminant concentrates, 225 representatively commercial ruminant concentrates samples and 75 meat and bone meal (including cattle, sheep, pig and poultry meat and bone meal) samples were collected in the People's Republic of China. Two hundred twenty five ruminant concentrates samples of adulterated meat and bone meal (0.5%-35%) were prepared including 135 calibration samples and 90 independent validation samples. For the calibration set samples, 3 samples were prepared at each concentration. For validation set samples, 2 samples were prepared at each concentration. Any one commercial ruminant concentrates was used once only. The spectra were scanned by raster near infrared diffuse reflectance spectroscopy instrument, and the effect of spectrum pretreatment methods (mathematic pretreatments and scatter correction) and spectrum region (visible and NIR) on the calibration results was considered. The calibration equation was established by modified partial least squares method. The result showed that the calibration gave r2 of 0.979, a standard error of calibration (SEC) of 1.522% and a standard error of cross validation (SECV) of 1.582%. The 90 independent validation samples were used to validate the quantitative equation. The r2, a standard error of prediction (SEP) and ratio of performance to standard deviation (RPD) were 0.972, 1.764% and 5.99 respectively. The results of this study indicated that near infrared diffuse reflectance spectroscopy method could provide rapidly quantitative prediction for meat and bone meal percent in ruminant concentrates. This method was significant in practice for enriching the rapidly quantitative methods of determining animal feed materials.