Comparison between Calibrations of Fish Oil and AkoFeed Examined with Near-Infrared Light for Use in Animal Feed

Sammanfattning: The aim with this master thesis was to investigate if a certain sow feed requires different calibrations in near-infrared analysis, due to if the sow feed have fish oil or AkoFeed as fat source. To investigate this, a basic sow feed mix was prepared and divided in 60 jars with 250 g in each. In 30 of the jars 0 to 15 g fish oil were added and in the other 30 jars 0 to 21 g AkoFeed were added. 2/3 of the jars were used for calibration and 1/3 were used as external validation sets. Then, all 60 samples were analyzed in NIR and spectra from 950 nm to 1650 nm were obtained. Additionally, the content of the nutrients water, protein, ash, fat and crude fiber were analyzed in the laboratory for some of the samples and calculated for the rest of the samples. The calibration method PLS was used and three calibrations were made for the samples containing fish oil, AkoFeed and a combination of both. To investigate if there were any difference between the calibrations, they were validated by comparisons of the error values R2 and RMSEP. However, the calibration of the fish oil indicated to be better than the calibrations of AkoFeed and the combination. Therefore, better predicted values of unknown samples of the sow feed containing fish oil would be obtained if the calibrations are separate, while it does not matter for the predicted values of the sow feed containing AkoFeed.