SEARCH · Search PubMed
Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.
Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
Explore the source record for details and available documents.
On the basis of existing information it is, perhaps, useful to propose tentative preliminary figures for somatic nutrient requirements (Table 2). Such a proposal may serve as a focus for research to clarify more precisely the somatic requirements for a given production function in a given species. The requirements, therefore, are presented as interspecies generalizations and are calculated per kilogram of metabolic body size for the maintenance of adult animals. Only those nutrients for which there are some experimental data are included, so the absence of a given nutrient is an indication that it has not been studied. The figure for energy was derived by subtracting from the metabolizable energy for maintenance those heat losses associated with bacterial action and with prehension and transport of food. The resulting value was then increased by an amount representing the relative inefficiency of VFA, as compared with glucose metabolism. Amino acid values are essentially those obtained by intravenous administration. Water-soluble vitamin values except for thiamin were not listed because they were not expected to differ from whole-body requirements. Thiamin data were based on the work of Mueller & Asplund (51). The most obvious need is for definitive values for the amino acid requirements for productive functions and for water-soluble vitamin data. In the absence of such data, experiments with supplementation of these nutrients will continue to be haphazard and arbitrary. (Table: see text).
Bicarbonate appearance in the lumen and its relationship to solute absorption were studied in a Pavlov pouch in the cardiac region of the first compartment of the llama forestomach. HCO3- appearance showed no diurnal variation. HCO3- accumulation was highly dependent on the pH of the solution used. The HCO3- ion probably is formed from CO2 diffusing into the lumen from the serosal side, as a result of cell metabolism and of OH- ions. HCO3- accumulation was closely related to volatile fatty acid (VFA) absorption. The ratio of HCO3- appearance to VFA absorption depended on the pH of the solution. At a pH of 6.6, about 0.1 mol HCO3- and, at a pH of 7.8, 0.9 mol HCO3- appeared per mole absorbed VFA, indicating that at slightly alkaline pH nearly all H+ ions required for the nonionic absorption of VFA appeared to be delivered from the dissociation of H2CO3. Bicarbonate gain and VFA absorption were increased when animals were not fed for 48 h. Sodium absorption was related to VFA as well as water absorption.