Show simple item record

dc.contributor.authorBalcells Terés, Joaquim
dc.contributor.authorGuada, J. A.
dc.contributor.authorCastrillo, C.
dc.contributor.authorGasa, J.
dc.date.accessioned2018-10-16T09:28:29Z
dc.date.available2018-10-16T09:28:29Z
dc.date.issued1993
dc.identifier.issn0007-1145
dc.identifier.urihttp://hdl.handle.net/10459.1/64885
dc.description.abstractThe present study examined the effect of urea-N supplementation of a N-deficient diet on digestion and metabolism in the rumen. Five Rasa Aragonesa ewes, each fitted with a rumen cannula, were offered alkali-treated barley straw ad lib. alone or supplemented continuously via the cannula with four levels of urea-N (3, 6, 9 and 12g/d). Rumen NH, concentrations increased in response to urea infusion (6128 mgfl; P < 0.001). At the highest level of rumen NH, concentration there was a significant increase, compared with the unsupplemented treatment, in dry matter (DM) intake (8461206 g/d; P < 0.001) and apparent digestibility of DM (0.38443), organic matter (0.38-0.45) and neutraldetergent fibre (0.41-0.49; P < 0.01). Rumen outflow rates of particulate matter and potential DM disappearances, assessed using nylon bags, were not affected by the experimental treatments, although fractional rate of DM disappearance increased significantly with increasing levels of urea infusion (2446per h). Urinary excretion of total purine derivatives increased with N supplementation, although the response was exclusively due to an increase in allantoin excretion (26.9-66.4 mg/kg live weight (W)07’ per d; P < 0,001). Xanthine, hypoxanthine and uric acid excretion rates were constant, averaging 1.8 (SE 0.17); 5.4 (SE 0.21) and 7.2 (SE 0.36) mg/kg W07s per d respectively. The maintenance of a minimum rumen NH, concentration (approximately 50 mg/l) was necessary to avoid significant reductions in DM intake and fermentation rate. Higher levels, however, may further increase microbial N flow at the duodenum, as suggested by the response in urinary allantoin excretion over the range of rumen NH, concentrations.ca_ES
dc.description.sponsorshipThis work has been supported by the CICYT Project GAN 91-1050-C02-01.ca_ES
dc.language.isoengca_ES
dc.publisherCambridge University Pressca_ES
dc.relation.isformatofReproducció del document publicat a https://doi.org/10.1079/BJN19930073ca_ES
dc.relation.ispartofBritish Journal of Nutrition,1993, vol. 69, p. 721-732ca_ES
dc.rights(c) Cambridge University Press, 1993ca_ES
dc.subjectRumen ammoniaca_ES
dc.subjectPurine excretionca_ES
dc.subjectSheepca_ES
dc.titleRumen digestion and urinary excretion of purine derivatives in response to urea supplementation of sodium-treated straw fed to sheepca_ES
dc.typeinfo:eu-repo/semantics/articleca_ES
dc.identifier.idgrec021677
dc.type.versioninfo:eu-repo/semantics/publishedVersionca_ES
dc.rights.accessRightsinfo:eu-repo/semantics/openAccessca_ES
dc.identifier.doihttps://doi.org/10.1079/BJN19930073


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record