Effects of considering the rate of comminution of particles and microbial contamination on accuracy of in situ studies of feed protein degradability in ruminants |
| |
| Institution: | 1. Swedish University of Agricultural Sciences, Department of Agricultural Research for Northern Sweden, SE-901 83 Umeå, Sweden;2. Natural Resources Institute Finland (Luke), FI-31600 Jokioinen, Finland;3. Valio Ltd., Farm Services, PO Box 10, FI-00039 Valio, Finland;1. Institute of Bioscience, Universiti Putra Malaysia, UPM Serdang, 43400 Selangor, Malaysia;2. Faculty of Biotechnology and Biomolecular Sciences, Universiti Putra Malaysia, UPM Serdang, 43400 Selangor, Malaysia;3. School of Science, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, 47500 Selangor, Malaysia;4. Genomics Facility, Tropical Medicine Biology Platform, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway, 47500 Selangor, Malaysia;5. Institute of Tropical Agriculture, Universiti Putra Malaysia, UPM Serdang, 43400 Selangor, Malaysia;6. Biotechnology Research Institute, Universiti Malaysia Sabah, Kota Kinabalu, Sabah 88999, Malaysia;1. University of Nottingham, School of Geography, University of Nottingham, Nottingham NG7 2RD, UK;2. British Geological Survey, Kingsley Dunham Centre, Keyworth, Nottingham NG12 5GG, UK;1. Animal Production and Health Division, Food and Agriculture Organization of the United Nations, Viale delle Terme de Caracalla, 00153 Rome, Italy;2. Norsk Hestesenter, Starumsvegen 71, 2850 Lena, Norway;3. Instituto Nacional de Investigación y Tecnología Agraria y Alimentaria, Crta. de la Coruña, km 7,5, 28040 Madrid, Spain;4. Institut de l’Elevage, 149 rue de Bercy, 75595 Paris Cedex 12, France;5. REC Raumberg-Gumpenstein, Institute of Organic Farming and Farm Animal Biodiversity, 4601 Thalheim, Austria;6. Federación de Razas Autóctonas de Galicia, Fontefiz,s/n.32152.Coles, Ourense, Spain |
| |
| Abstract: | Ruminal degradation of dry matter (DM) and crude protein (CP) in samples of soybean meal (SBM), barley grain (BG) and lucerne hay (LH) were measured by an in situ ruminal technique considering either only the outflow rate of particles from the rumen (kp) or, both kp and rate of particle comminution (kc). The effect of correction for the microbial contamination using an 15N technique was also determined for LH. Degradation and transit studies were completed on three wethers cannulated in the rumen and duodenum and fed a mixed diet of LH and concentrate (2:1 on DM), at an intake level of 50 g DM/kg BW0.75. Transit studies of concentrates and forages were completed with SBM and LH samples marked with Yb and Eu, respectively. Mean values of kc were higher in SBM than in LH (0.357 versus 0.204 h, P < 0.05). The same trend was observed for kp (0.0587 versus 0.0452/h; P < 0.1). Apparent estimates of the proportion of rumen undegraded CP obtained using both rates were 0.884, 0.745 and 0.825 of those obtained using only kp (0.535, 0.247 and 0.303 for SBM, BG and LH, respectively). Differences occurred for SBM and LH (P < 0.01) and for BG (P < 0.05). The pattern of microbial contamination of LH, expressed as a proportion of residual DM or CP, fitted exponential curves with asymptotic values of 0.076 and 0.586, respectively. Correction for microbial contamination reduced (P < 0.05) estimates of undegraded CP from 0.303 to 0.238, which was further reduced to 0.178 (P < 0.01) when the effect of kc was also considered. |
| |
| Keywords: | |
| 本文献已被 ScienceDirect 等数据库收录！ |
|
