RUMEN FERMENTATION PATTERN IN GOATS AND SHEEP GRAZING PASTURES FROM SEMIARID SPANISH LANDS UNSUPPLEMENTED OR SUPPLEMENTED WITH BARLEY-GRAINOR BARLEY GRAIN-UREA

Citation
Ma. Garcia et al., RUMEN FERMENTATION PATTERN IN GOATS AND SHEEP GRAZING PASTURES FROM SEMIARID SPANISH LANDS UNSUPPLEMENTED OR SUPPLEMENTED WITH BARLEY-GRAINOR BARLEY GRAIN-UREA, Livestock production science, 39(1), 1994, pp. 81-84
Citations number
10
Categorie Soggetti
Agriculture Dairy & AnumalScience
ISSN journal
03016226
Volume
39
Issue
1
Year of publication
1994
Pages
81 - 84
Database
ISI
SICI code
0301-6226(1994)39:1<81:RFPIGA>2.0.ZU;2-P
Abstract
An experiment following a 2 (animal species) X 3 (phenological state) X 3 (feed supplementation) factorial design was carried out with sheep and goats grazing on semiarid lands in the south-east of Spain. Anima ls consumed, from early spring to late summer, pasture alone or pastur e supplemented with barley grain (88 g DM/an/d) or with barley grain p lus 1% urea. The animals were on a semiextensive management system. Ce ll wall content was always slightly higher in the pasture selected by sheep. Significant (P < 0.05) interspecies differences in ruminal pH, ammonia nitrogen (NH3-N) and total volatile fatty acids (VFA) concentr ations and in molar proportions of acetic, n-butyric, isobutyric, iso- valeric and n-valeric acids were found in samples taken just before gr azing. The contents of NH3-N, total VFA, acetic, propionic and n-butyr ic acids at the highest microbial activity times were similar. The phe nological state of the pasture had a significant effect (P < 0.05) on rumen NH3-N and total VFA contents. Supplementation with barley grain did not significantly change the rumen fermentation pattern, except fo r the n-valeric acid molar proportion which increased (P < 0.05) when barley was offered. This effect was not found when urea was added. It is concluded that there are differences in rumen fermentation pattern between sheep and goats. Those differences are influenced by the pheno logical state of the pasture but they are not affected by supplementat ion.