Analytical variation in metabolic profile testing
Summary Results are presented demonstrating quality control of the analytical procedures used during the application of metabolic profile tests to dairy herds over a period of 3 years. The significance of analytical variance is discussed in relation to the average population variance in dairy herds. It is concluded that analytical variance can be restricted to reasonable proportions providing that careful quality control is continuously employed.
A use of the computer as an aid in diagnosis of metabolic problems of dairy herds
Summary The contribution that the computer has made in the interpretation and analysis of a metabolic profile test, which is designed to monitor the metabolic health of a dairy herd and assess the adequacy of dietary intake for production, is described. The test is based on an assessment of blood chemistry for any number of variates, which constitute the metabolic profile, measured for randomly selected cows from 3 groups of a herd: dry cows, cows giving intermediate quantities of milk and cows giving high daily yields. The computer program is designed to give an objective and comprehensive assessment of the test in an easily interpretable form based on a pictorial form of print-out. The profile is displayed as a ‘histogram’ presented as standard deviations from the normal base-line, and for each variable a scatter diagram is included presenting the individual variates plotted against the particular animal's daily milk yield.
New Sweet-Tasting C21-Pregnane Glycosides from Pericarps of Myriopteron extensum.
Ten novel C21 pregnane glycosides, extensumside C-L (1-10), were isolated as highly sweet-tasting substances from the edible pericarps of Myriopteron extensum (Wight) K. Schum by sensory-guided fractionation and purification. Their structures were determined through 1D and 2D NMR, such as HSQC, HMBC, 1H-1H COSY, HSQC-TOCSY, and ROESY, as well as other spectroscopic analysis combined with chemical evidence. These compounds shared the same aglycone, 3β,16α-dihydroxy-pregn-5-en-20-one, and contained the deoxysugar chain and the glucose chain which were linked to C-3 and C-16 of the aglycone, respectively. The sweetness potency was evaluated by a human sensory panel test and preliminary structure-taste relationship was discussed. The sweetness intensities of these compounds are between 50 and 400 times greater than that of sucrose. Furthermore, quantitation analyses of compounds 1, 3, 4, and 6 in different parts of M. extensum indicated that the concentrations of these sweet components in the pericarps are obviously higher than those in stems and roots.