Rumen fermentation characteristics, nitrogen balance and growth in lambs fed methane digester effluent.
A laboratory silo trial, two lamb metabolism trials and a lamb growth trial were conducted to compare the nitrogen (N) value of swine methane digester effluent (MDE) to that of urea. Using laboratory silos (four/treatment), fermentation characteristics were measured for silages containing cracked corn, ground wheat straw and MDE added at levels of 0, 4, 8 or 12% of silage dry matter (DM). Lactic acid concentration increased linearly with up to 8% MDE addition, but then decreased (P less than .05; quadratic) with 12% MDE. Butyric acid was highest (P less than .05; linear) with 12% MDE, indicating an undesirable fermentation. In a metabolism study, DM, organic matter and N digestibilities and N balance were similar (P greater than .10) between urea and MDE, but DM digestibility was lower (P less than .05) for ensiled diets (52%) than diets fed fresh daily (59.4%). Mean ruminal volatile fatty acid, ruminal ammonia-N and plasma urea-N concentrations were similar (P greater than .10) between urea- and MDE-fed lambs. Plasma urea-N was higher (P less than .05) and ruminal isovaleric acid lower (P less than .05) in animals fed ensiled than fresh diets. In the second metabolism trial, digestibility of N was lowest (P less than .05) for MDE (51.2%) and highest for soybean meal (SBM; 71.8%), but N balance was similar among all diets.(ABSTRACT TRUNCATED AT 250 WORDS)
D000821:Animal Feed / Q000032:analysis; D000818:Animals; D001806:Blood Urea Nitrogen; D001835:Body Weight; D005232:Fatty Acids, Volatile / Q000378:metabolism; D005285:Fermentation; D006863:Hydrogen-Ion Concentration; D007773:Lactates / Q000032:analysis; D019344:Lactic Acid; D008297:Male; D008372:Manure; D009584:Nitrogen / Q000378:metabolism*; D012417:Rumen / Q000378:metabolism*; D012756:Sheep / Q000254:growth & development / Q000378:metabolism*; D012820:Silage / Q000032:analysis; D014508:Urea
D005232:Fatty Acids, Volatile; D007773:Lactates; D008372:Manure; D019344:Lactic Acid; D014508:Urea; D009584:Nitrogen