Ruminal bacteria and protozoa composition, digestibility, and amino acid profile determined by multiple hydrolysis times

S. W. Fessenden, T. J. Hackmann, D. A. Ross, A. Foskolos, M. E. Van Amburgh

Allbwn ymchwil: Cyfraniad at gyfnodolynErthygladolygiad gan gymheiriaid

13 Dyfyniadau(SciVal)
133 Wedi eu Llwytho i Lawr (Pure)

Crynodeb

Microbial samples from 4 independent experiments in lactating dairy cattle were obtained and analyzed for nutrient composition, AA digestibility, and AA profile after multiple hydrolysis times ranging from 2 to 168 h. Similar bacterial and protozoal isolation techniques were used for all isolations. Omasal bacteria and protozoa samples were analyzed for AA digestibility using a new in vitro technique. Multiple time point hydrolysis and least squares nonlinear regression were used to determine the AA content of omasal bacteria and protozoa, and equivalency comparisons were made against single time point hydrolysis. Formalin was used in 1 experiment, which negatively affected AA digestibility and likely limited the complete release of AA during acid hydrolysis. The mean AA digestibility was 87.8 and 81.6% for non-formalin-treated bacteria and protozoa, respectively. Preservation of microbe samples in formalin likely decreased recovery of several individual AA. Results from the multiple time point hydrolysis indicated that Ile, Val, and Met hydrolyzed at a slower rate compared with other essential AA. Singe time point hydrolysis was found to be nonequivalent to multiple time point hydrolysis when considering biologically important changes in estimated microbial AA profiles. Several AA, including Met, Ile, and Val, were underpredicted using AA determination after a single 24-h hydrolysis. Models for predicting postruminal supply of AA might need to consider potential bias present in postruminal AA flow literature when AA determinations are performed after single time point hydrolysis and when using formalin as a preservative for microbial samples.

Iaith wreiddiolSaesneg
Tudalennau (o-i)7211-7226
Nifer y tudalennau16
CyfnodolynJournal of Dairy Science
Cyfrol100
Rhif cyhoeddi9
Dyddiad ar-lein cynnar28 Meh 2017
Dynodwyr Gwrthrych Digidol (DOIs)
StatwsCyhoeddwyd - 01 Medi 2017

Ôl bys

Gweld gwybodaeth am bynciau ymchwil 'Ruminal bacteria and protozoa composition, digestibility, and amino acid profile determined by multiple hydrolysis times'. Gyda’i gilydd, maen nhw’n ffurfio ôl bys unigryw.

Dyfynnu hyn