Using microbial fatty acids to improve understanding of the contribution of solid associated bacteria to microbial mass in the rumen

• Type: Article in International Scientific Journal
• Date: 2009

Authors

Bessa, RJB (Author) Other; Maia, MRG (Author) ICBAS; Jeronimo, E (Author) Other; Belo, AT (Author) Other; A. Cabrita (Author) FCUP; Dewhurst, RJ (Author) Other; Antonio J M Fonseca (Author) ICBAS

Journal

Title: Animal Feed Science and Technology

Vol. 150

Pages: 197-206

ISSN: 0377-8401

Publisher: Elsevier

Indexing

ISI Web of Knowledge - 28 Citations

Scopus - 30 Citations

Scientific classification

CORDIS: Natural sciences > Agrarian Sciences > Zootechnics

FOS: Agrarian Sciences > Animal and Dairy science

Other information

Authenticus ID: P-003-KTP

DOI: 10.1016/j.anifeedsci.2008.09.005

Abstract (EN): This study sought to distinguish liquid-(LAB) and detached (SAB(1)) and undetached (SAB(2))solid-associated bacteria through their fatty acid (FA) and purine base (PB) profiles. Fatty acids and PB were also evaluated as internal microbial markers for estimating microbial biomass associated with rumen particles. Four merino rams fitted with rumen cannulae and fed dehydrated alfalfa pellets provided rumen contents. In 3 consecutive weeks, rumen contents were collected and samples of LAB and SAB1, total rumen content (TRC), washed rumen particles (WRP) and rumen particles after SABI extraction (ERP) were obtained and analysed for PB and FA. The SAB2 biomass composition was estimated from the non-NDF organic matter (CM) remaining in ERR The concentration of total SAB biomass in particles was estimated using both PB and odd and branched-chain fatty acids (OBCFA). Concentrations of PB and OBCFA were highly correlated among the different rumen fractions. Marked differences between LAB and SAB populations occurred with LAB having higher PB content, lower FA content and a higher proportion (g/100g fatty acids) of OBCFA than did SAB. The chemical composition of SAB(1) and SAB(2) was similar, except for the 15% higher crude protein content of the latter. The concentration of OBCFA (mg/g microbial OM) did not differ between bacterial fractions. The PB/OBCFA ratio (mg/mg) was higher in LAB (2.08) than in SAB (0.94). The ratio between branched-chain and odd-linear-chain FA was higher in LAB (2.26) than in SAB (1.46). Extraction of PB and OBCFA from WRP with our SAB detachment procedure was 61% and 31%, respectively. Estimated SAB(1) and total SAB biomass (mg OM/g WRP) were 158 and 266, and 47 and 164, respectively, using PB and OBCFA as microbial markers. This study suggests that the OBCFA have potential as internal microbial markers in rumen ecosystem studies.

Language: English

Type (Professor's evaluation): Scientific

No. of pages: 10