SciELO - Scientific Electronic Library Online

vol.42 número5Fatty acid composition and oxidative stability of lambs' meat as affected by a bioflavonoid antioxidant and fat sourcesEvaluation of silver nanoparticles as a possible coccidiostat in broiler production índice de autoresíndice de assuntospesquisa de artigos
Home Pagelista alfabética de periódicos  

Serviços Personalizados



Links relacionados

  • Em processo de indexaçãoCitado por Google
  • Em processo de indexaçãoSimilares em Google


South African Journal of Animal Science

versão On-line ISSN 2221-4062
versão impressa ISSN 0375-1589


VAN DE VYVER, W.F.J.  e  USENI, B.A.. Digestion and microbial protein synthesis in sheep as affected by exogenous fibrolytic enzymes. S. Afr. j. anim. sci. [online]. 2012, vol.42, n.5, pp.488-492. ISSN 2221-4062.

The aim of the study was to determine the effect of an exogenous fibrolytic enzyme (EFE) on the ruminal disappearance of dry matter (DM), neutral detergent fibre (NDF), crude protein (CP) and on the microbial protein synthesis (MPS) in sheep of a milled substrate consisting of a 50 : 50 mixture of lucerne hay (LH) and wheat straw (WS). Four cannulated Döhne-Merino sheep were randomly assigned to two groups in a 2 x 2 cross-over experiment. Additional to the in situ study, the effects of an exogenous fibrolytic enzyme (EFE) on the in vitro gas production (GP) and ANKOM digestion systems on the mixture of milled LH and WS were determined. The substrate was pre-treated with distilled water (control) or EFE (treatment) 12 hours prior to incubation to allow interaction between the substrate and enzyme. Adding EFE significantly improved the in vitro cumulative gas production (GP), but it did not affect the in vitro MPS measured as purine derivates of the GP residues. The enzyme significantly increased the in vitro DM and NDF disappearances after 36 hours. However, the in situ disappearances of DM, NDF and CP of the roughage mixture were not affected by the EFE. Further, the in situ MPS was increased significantly with the EFE treatment of the mixed substrate. It is concluded that the improved ruminal digestion of DM, NDF and CP is not only due to direct enzyme hydrolysis, but also due to the improvement of MPS.

Palavras-chave : Fibre digestion; in vitro and in situ digestion; ruminants.

        · texto em Inglês     · Inglês ( pdf )


Creative Commons License Todo o conteúdo deste periódico, exceto onde está identificado, está licenciado sob uma Licença Creative Commons