Rowett Research Institute

About: Rowett Research Institute is a based out in . It is known for research contribution in the topics: Rumen & Population. The organization has 2986 authors who have published 4459 publications receiving 239472 citations.

Measurement of purine derivatives in urine of ruminants using automated methods

Abstract: Automated methods based on the Auto Analyzer have been developed for the analysis of allantoin, uric acid and xanthine plus hypoxanthine in urine of sheep and cattle. Allantoin is determined by a modification of an existing method. Recovery of allantoin added to urine was 99.7% ± 3.2 SD. Uric acid is determined using a phosphotungstic acid method, and xanthine and hypoxanthine together are determined as uric acid after treatment with xanthine oxidase. The enzymic conversion is integrated into the automated procedure of uric acid analysis. Recovery of uric acid, xanthine and hypoxanthine, all as uric acid, was 97–99%. The relative proportions of allantoin: uricacid: xanthine plus hypoxanthine in urine of sheep differed from those in urine of cattle. Xanthine and hypoxanthine were almost absent from urine of cattle.

Central melatonin receptors in the rainbow trout: comparative distribution of ligand binding and gene expression.

Abstract: To better define the role of melatonin in fish, we have compared in detail the distribution of 2-[125I]iodomelatonin binding sites with gene expression for melatonin receptor subtypes in a widely studied seasonal species, the rainbow trout. Three distinct partial sequences of the melatonin receptor gene were cloned from trout genomic DNA. Two of the sequences corresponded to the Mel1a receptor subtype, and one corresponded to the Mel1b receptor subtype. Analysis of numerous clones failed to find a sequence equivalent to the Mel1c receptor subtype. Comparison of receptor gene expression with 2-[125I]iodomelatonin binding distribution indicated dendritic transport of the receptor. Melatonin receptors were associated predominantly with visually related areas of the trout brain, such as the thalamic region, the pretectal area, and the optic tectum. The pituitary was devoid of 2-[125I]iodomelatonin binding, and melatonin receptor gene expression was not detectable. It would appear from the results of the present study that melatonin in this species is involved primarily in the processing of visual signals. How melatonin interacts with circannual rhythms of growth and reproduction is unclear, although a direct interaction between melatonin and the hypothalamopituitary axis is not clearly indicated. J. Comp. Neurol. 409:313–324, 1999. © 1999 Wiley-Liss, Inc.

Rumen degradation of straw 2. Botanical fractions of straw from two barley cultivars

Abstract: Two varieties of barley straw, Corgi and Gerbel, which varied in degradability when incubated in the rumen in nylon bags, were chosen for further examination of botanical fractions and to see how each fraction responded to treatment with ammonia. The straws were separated into leaves, internodes, nodes and chaff. The average proportions of these fractions were respectively 0·499, 0·380, 0·055 and 0·065 in Corgi straw and 0·404, 0·512, 0·059 and 0·025 in Gerbel straw. For both varieties the degradability of the botanical fractions were leaves > chaff > nodes > internodes.Despite a similar chemical composition, the dry-matter loss (DML) values of leaves, internodes and nodes of Corgi were higher than those of Gerbel straw.The differences between varieties were larger for internodes and nodes than for leaves. The difference in DML of the two varieties at 48-h incubation was 132 g/kg DM. Of this difference, 25 g were due to differences in distribution of the botanical fractions and 107 g to differences in DML of the fractions.Ammonia treatment significantly increased the DML of all fractions except the nodes. The overall improvement due to ammonia treatment of the different fraction was internode > chaff > leaves > nodes.