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The present study aimed to evaluate the effect of copra meal (the waste coconut of the oil industry) on in vitro ruminal kinetic and greenhouse gases production and on in vivo lamb performance. Twenty-eight male Rambouillet sheep (initial body weight 24.5 ± 3.9 kg) were randomly assigned to one of the four treatments: 0, 50, 100, and 150 g of copra meal/kg in their diet (dry matter basis). Final weight, weight gain, and feed intake were not affected (p > 0.05) by the copra meal addition. The gas production volume (V) decreased, and the gas production rate increased, in a linear trend (p < 0.05) as copra meal was added to the diet. In contrast, methane and CO2 production showed an opposite quadratic trend (p < 0.05), with the highest and lowest values reported at 100 g/kg DM of copra meal, respectively. The addition of copra meal in the lambs' diet decreases the volume of gas production and is a strategy to decrease methane and carbon dioxide production in feeding without affecting animal performance. [ABSTRACT FROM AUTHOR]

Clavibacter michiganensis subsp. michiganesis ( Cmm ) is a quarantine-worthy pest in México. The implementation and validation of new technologies is necessary to reduce the time for bacterial detection in laboratory conditions and Raman spectroscopy is an ambitious technology that has all of the features needed to characterize and identify bacteria. Under controlled conditions a contagion process was induced with Cmm , the disease epidemiology was monitored. Micro-Raman spectroscopy (532 nm λ laser) technique was evaluated its performance at assisting on Cmm detection through its characteristic Raman spectrum fingerprint. Our experiment was conducted with tomato plants in a completely randomized block experimental design (13 plants × 4 rows). The Cmm infection was confirmed by 16S rDNA and plants showed symptoms from 48 to 72 h after inoculation, the evolution of the incidence and severity on plant population varied over time and it kept an aggregated spatial pattern. The contagion process reached 79% just 24 days after the epidemic was induced. Micro-Raman spectroscopy proved its speed, efficiency and usefulness as a non-destructive method for the preliminary detection of Cmm . Carotenoid specific bands with wavelengths at 1146 and 1510 cm -1 were the distinguishable markers. Chemometric analyses showed the best performance by the implementation of PCA-LDA supervised classification algorithms applied over Raman spectrum data with 100% of performance in metrics of classifiers (sensitivity, specificity, accuracy, negative and positive predictive value) that allowed us to differentiate Cmm from other endophytic bacteria ( Bacillus and Pantoea ). The unsupervised KMeans algorithm showed good performance (100, 96, 98, 91 y 100%, respectively).