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.

Winter food restriction and summer compensation in red deer stags (Cervus elaphus).

Abstract: 1. Twelve red deer stags (Cervus elaphus) penned individually from weaning were fed on a concentrate diet. Six stags received the diet to appetite throughout the study, and the other six were restricted to 70% of the intake of the first group during winter and then fed to appetite during summer.2. The winter-restricted stags showed remarkable compensatory growth during summer. Compared with the unrestricted stags they showed greater food intake, greater daily live-weight gain and increased food conversion efficiency. Nonetheless, they failed to compensate fully for the previous undernutrition.3. The hind-foot of the restricted stags failed to grow as long as that of the unrestricted stags.4. Poor winter nutrition, particularly during the first year of life, and subsequent failure to compensate during the short periods of summer plenty, provides an explanation for the small mature size of wild stags in Scotland.5. Although the winter-restricted stags were less fat both grossly and relative to body-weight than the unrestricted stags, both groups showed the same relationship of level of fatness to empty-body-weight. In both the groups of stags, extensive fat deposition began once they had reached about half their expected mature weight, a much later stage of development and age than in sheep and cattle.6. The annual cycle of growth and appetite is considered to form part of a complex adaptive system to enhance survival in a harsh seasonal environment followed by a mild seasonal environment. On Scottish hills deer reach a size appropriate to their environment rather than their genetic potential size.

The effects of early zinc deficiency on DNA and protein synthesis in the rat.

Abstract: 1. The effects of early zinc deficiency on DNA and protein metabolism of the liver, kidneys, testes and spleen of the young rat were studied. The investigations were carried out in two phases: before food consumption and growth were affected, and afterwards. 2. The incorporation of [ 3 H]thymidine into DNA was markedly affected by differences of less than a week in the age of the rats. 3. Zn deficiency significantly reduced the incorporation of [ 3 H]thymidine into DNA of liver, kidneys and spleen before growth and food consumption were affected. The degree of inhibition was of the order of 50% in the first 5 d. A similar but non-significant trend was observed for the testes. 4. The incorporation of [ 3 C]lysine into protein was not significantly affected in liver and testes during the initial period of Zn deficiency; the incorporation into kidneys and spleen was significantly inhibited but the magnitude of the effect was only of the order of 20% in 5d. 5. One week after the start of the second phase, the concentration of DNA in liver, testes, and spleen of Zn-deficient animals was not significantly different from that in pair-fed controls. The DNA content of the kidneys was significantly reduced by the deficiency hut only to 97% of that in pair-fed animalsgiven the Zn-supplcmenteddiet. The incorporation of [ 3 H]thymidine into DNA was not significantly different between deficient and control groups in any of the four organs investigated.

Mechanistic Models of Forage Cell Wall Degradation

Abstract: This chapter is concerned primarily with the molecular events that occur when forage plant cell walls are degraded by gut microorganisms. As such it is narrowly focused and is concerned with the individual cell wall or part of the cell wall rather than forages per se. It is important to place these molecu­ lar or "mural" events into an appropriate botanical and ecological context and to recognize that many factors other than cell wall composition and ar­ chitecture influence the nutritive value of a forage and its cell wall fraction when consumed by an animal. All forages are composed of a heterogeneous population of cell types, each of which has a cell wall with unique properties. Forages differ in the potential nutritive value of their cell wall (fiber) fraction because of differ­ ences in both the amount of cell walls derived from the various cell types consumed by the animal and their individual degradabilities. Currently, no routine methods exist for estimating the weight of the various cell types con­ sumed and few measurements have been made of the degradability of cell walls from individual cell types. Certainly no comparative studies between forage species or cultivars based on such methods have been attempted. At best, estimates of leaf, leaf sheath, and stem ratios have been made which reflect, at a morphological level, variations in amounts of different cell types present (e.g., Wilman & Altimimi, 1982; Nordkvist et aI., 1987). Although a relatively crude indicator, morphological measurements have the value of demonstrating the importance of changes in the proportion of cell types present in determining the digestion characteristics of the forage. A com­ parison of barley straw (Hordeum vulgare L.) cultivars with degradability values ranging from 40 to 60070 indicated that approximately one-half of the differences in overall cell wall degradability could be attributed to the varia­ tion in plant morphology, the more degradable cultivars having the highest leaf blade and lowest stem content (Goto et aI., 1991).

Response of protein synthesis in human skeletal muscle to insulin: an investigation with L-[2H5]phenylalanine

Abstract: The role of insulin in the regulation of muscle protein synthesis in adult humans has been investigated with intravenous infusion of insulin at levels comparable with those observed after normal fe...