The Near-Infrared Spectroscopy of Ethanol-Fixed Tissues to Detect Illicit Treatments with Glucocorticoids in Bulls.

This study aimed to set up indirect, rapid methods involving near infrared (NIR) spectroscopy analysis, to detect illicit treatments with glucocorticoids in bull. The ethanol fixation method (EtOH) was applied to 7 different tissues obtained from 20 Friesian bulls, 12 of which were experimentally administered with dexamethasone as part of a growth-promoting protocol for 60 days and slaughtered 26 days after the end of the treatment. A perfect discrimination was obtained for the 7 sampled tissues, considering a full UV-Vis-NIR range (350 ÷ 2500 nm), for both false positive and negative animals. The validated true positive and negative errors were zero for the longissimus thoracis muscle, 10% for the skin-dermis, 15% for the fat, 25% for the thymus gland and the semitendinosus muscle, 30% for the sternomandibularis muscle and 35% for the skin-hair. A multiple test on the most accessible tissues, that is, the thymus gland, the sternomandibularis muscle and fat, can be used as an alternative to provide indications about animals that have been subjected to illicit treatments. In the short space of three days from the slaughter, NIR spectroscopy of ETOH fixed tissues, would allow at least cost the detection of a probable illicit which could eventually be reported to health authorities for specific investigation in the frame of official controls.

Carbon monoxide stunning of Atlantic salmon (Salmo salar L.) modifies rigor mortis and sensory traits as revealed by NIRS and other instruments.

BACKGROUND: Methods of stunning used in salmon slaughter are still the subject of research. Fish quality can be influenced by pre-, ante- and post-mortem conditions, including handling before slaughter, slaughter methods and storage conditions. Carbon monoxide (CO) is known to improve colour stability in red muscle and to reduce microbial growth and lipid oxidation in live fish exposed to CO. Quality differences in Atlantic salmon, Salmo salar L., stunned by CO or percussion, were evaluated and compared by different techniques [near infrared reflectance spectroscopy (NIRS), electronic nose (EN), electronic tongue (ET)] and sensory analysis. RESULTS: Thawed samples, freeze-dried preparates and NIRS devices proved to be the most efficient combinations for discriminating the treatments applied to salmon, i.e. first the stunning methods adopted, then the back-prediction of the maximum time to reach rigor mortis and finally to correlate some sensory attributes. A trained panel found significant differences between control and CO-stunned salmon: reduced tactile crumbliness, reduced odour and aroma intensities, and reduced tenderness of CO-treated fillets. CO stunning reduced radiation absorbance in spectra of thawed and freeze-dried fillets, but not fillet samples stored in ethanol, where it may have interacted with myoglobin and myosin. CONCLUSIONS: The good results in a rapid discrimination of thawed samples detected by NIRS suggest suitable applications in the fish industry. CO treatment could mitigate sensory perception, but consumer tests are needed to confirm our findings. © 2015 Society of Chemical Industry.

Rabbit Feces as Feed for Ruminants and as an Energy Source.

There are prospects for using novel feeds from various sources to provide ruminants with alternative sources of protein and energy such as by-products, and animal wastes. Rabbit feces are a concentrated source of fiber and could have commercial potential both as input biomass in anaerobic processes for biogas production, as well as a fibrous source for ruminal degradation. The aims of this work were to assess the potential as ruminant feeding and as biogas production of rabbit feces, in comparison with 12 crops. The chemical composition and the potential and experimental in vitro true digestibility (IVTD) and neutral detergent fiber digestibility (NDFD) of 148 feces samples were determined by using chemical methods, Daisy system digestibility and/or NIRS predictions. The average biomethane potential (BMP) was 286 ± 10 lCH4/kg SV with -4% vs. the crops average. Milk forage unit (milk FU), IVTD and NDFD of feces were 0.54 ± 0.06 milk FU/kg DM, 74% ± 3% and 50% ± 5%, respectively, with comparisons of -19%, -11% and -24% vs. the crops average. Reconstruction of the potential values based on the chemical constituents but using the crop partial least square model well agreed with the NIRS calibrations and cross-validation. In a global NIRS calibration of the feces and crops the relative predicted deviation for IVTD, NDFD and milk FU were 3.1, 2.9 and 2.6, respectively, and only 1.5 for BMP. Running the Daisy system for rabbit feces in rumen fluid gave some inconsistencies, weakened the functional relationships, and appeared not to be correlated with the potential values of IVTD and NDFD. Nevertheless, the energetic potential of feces appears to be similar to some conventional crops at different degrees of maturity. Thus we conclude that rabbit feces has potential value as a ruminant feed and for biogas production.

Electronic Nose analysis of milk from cows grazing on two different Alpine vegetation types.

The nutritional distinctiveness of pasture-fed dairy products is mainly influenced by the transfer of specific chemical compounds from the grass to the milk and by their effect on rumen microflora and animal metabolism. Thus, the pasture-fed origin has to be objectively proven, using fast and reproducible analytical methods applied to finished products, in order to protect consumers against potential frauds. In this work, Electronic Nose patterns of Alpine milks produced by cows grazing Trifolium alpinum and Festuca nigrescens pasture types have been examined, in order to test the potential use of this device for routine control analyses of the botanical origin of milk and dairy products. The data have been treated with different multivariate analyses (MANOVA, LDA) and chemometrics (MPLS). The results allow a very good classification of the milks, according to the two treatments. Such results demonstrate that this device could be successfully applied to PDO dairy products food chain as a tool for the determination of their dietary origin.