Relationship of Nitrogen Metabolism Capacity, Carcass Quality, and Expression of Glutamate Transporters and Metabolizing Enzymes in Polypay and Percentage White Dorper Lambs
Year: 2007
Type: dissertation
Abstract: Two studies were conducted to compare nitrogen (N) and glutamate metabolism in Polypay and percentage White Dorper lambs.First, a two-phase digestion/N metabolism trial was conducted with 18 wether lambs of three genetic types: Polypay (PP), 1/2 White Dorper 1/2 Polypay (1/2 D), and 3/4 White Dorper 1/4 Polypay (3/4 D). Six lambs of each genetic type were fed a high roughage diet (HR; Phase 1) or high concentrate diet (HC; Phase 2). DM and N digestion was higher for 1/2 D than PP or 3/4 D fed HC. N retention was highest for 1/2 D regardless of diet.The second study analyzed the effect of genetic type on glutamate transporter and metabolizing enzyme expression in liver, kidney, longissimus dorsi muscle (LD muscle), and subcutaneous fat (Sub Q Fat) tissue of 18 wether lambs of three genetic types: PP, 1/2 D, and 15 /16 White Dorper 1/16 Polypay (15 /16 D). Tissue samples were analyzed for protein and mRNA content of GS, GDH, ALT, EAAC1, and GLT-1. Glutamate transport and metabolism capacity was lowest for the heavier muscled 15 /16 D lambs.The results suggest genetic type has an effect on N metabolism due to differential expression of glutamate transporters and metabolizing enzymes.
Author: Andrea K. Lunsford
Institution: University of Kentucky
Language: English
Subfield: Agronomy and Crop Science
Domain: Life Sciences
SDG: Zero hunger
Open Access status: green
OpenAlex ID: W1504081683