Skip to main content
Article thumbnail
Location of Repository

Selenium persistency and speciation in the tissues of lambs following the withdrawal of dietary high-dose selenium-enriched yeast

By Darren Thomas Juniper, Richard Hartley Phipps, Eva Ramos-Morales and Gérard Bertin

Abstract

The objective was to determine the concentration of total selenium (Se) and the proportion of total Se comprised as selenomethionine (SeMet) and selenocysteine (SeCys) in post mortem tissues of lambs in the six weeks period following the withdrawal of a diet containing high dose selenized yeast (SY), derived from a specific strain of Saccharomyces cerevisae CNCM (Collection Nationale de Culture de Micro-organism) I-3060. Thirty Texel x Suffolk lambs used in this study had previously received diets (91 days) containing either high dose SY (HSY; 6.30 mg Se/kg DM) or an unsupplemented control (C; 0.13 mg Se/kg DM). Following the period of supplementation all lambs were then offered a complete pelleted diet, without additional Se (0.15 mg Se/kg DM), for 42 days. At enrollment and 21 and 42 days later, five lambs from each treatment were blood sampled, euthanased and samples of heart, liver, kidney and skeletal muscle (Longissimus Dorsi and Psoas Major) tissue were retained. Total Se concentration in whole blood and tissues was significantly (P < 0.001) higher in HSY lambs at all time points that had previously received long term exposure to high dietary concentrations of SY. The distribution of total Se and the proportions of total Se comprised as SeMet and SeCys differed between tissues, treatment and time points. Total Se was greatest in HSY liver and kidney (22.64 and 18.96 mg Se/kg DM, respectively) and SeCys comprised the greatest proportion of total Se. Conversely, cardiac and skeletal muscle (Longissimus Dorsi and Psoas Major) tissues had lower total Se concentration (10.80, 7.02 and 7.82 mg Se/kg DM, respectively) and SeMet was the predominant selenized amino acid. Rates of Se clearance in HSY liver (307 µg Se/day) and kidney (238 µg Se/day) were higher compared with HSY cardiac tissue (120 µg Se/day) and skeletal muscle (20 µg Se/day). In conclusion differences in Se clearance rates were different between tissue types, reflecting the relative metabolic activity of each tissue, and appear to be dependant upon the proportions of total Se comprised as either SeMet or SeCys

Topics: 571
Publisher: Cambridge University Press
Year: 2008
OAI identifier: oai:centaur.reading.ac.uk:4422

Suggested articles

Citations

  1. Agriculture, Fisheries and Food 1982. The Feedingstuffs (sampling and analysis)
  2. (2001). amending Council Directive 87/153/EEC fixing guidelines for the assessment of additives in animal nutrition
  3. (1986). Animal Scientific Procedures Act
  4. (2004). Effect of supranutritional and organically bound selenium on performance carcass characteristics and selenium distribution in finishing beef steers.
  5. (1968). Enzyme method for determination of a-linked glucose polymers in biological materials.
  6. (1988). Metabolism of selenite, selenomethionine and feedincorporated selenium in lactating goats and dairy cows.
  7. (2006). Selenium supplementation of lactating dairy cows: Effect on selenium concentration in blood, milk, urine and feces.
  8. (2006). Tolerance of inorganic selenium by range-type ewes during gestation and lactation.
  9. (2005). Tolerance of inorganic selenium in wether sheep.
  10. (1986). Vainio A and Edelmann K

To submit an update or takedown request for this paper, please submit an Update/Correction/Removal Request.