title: Optimal Cultivation Time for Yeast and Lactic Acid Bacteria in Fermented Milk and Effects of Fermented Soybean Meal on Rumen Degradability Using Nylon Bag Technique.
abstract: The objectives of this study were to determine an optimal cultivation time for populations of yeast and lactic acid bacteria (LAB) co-cultured in fermented milk and effects of soybean meal fermented milk (SBMFM) supplementation on rumen degradability in beef cattle using nylon bag technique. The study on an optimal cultivation time for yeast and LAB growth in fermented milk was determined at 0, 4, 8, 24, 48, 72, and 96 h post-cultivation. After fermenting for 4 days, an optimal cultivation time of yeast and LAB in fermented milk was selected and used for making the SBMFM product to study nylon bag technique. Two ruminal fistulated beef cattle (410±10 kg) were used to study on the effect of SBMFM supplementation (0%, 3%, and 5% of total concentrate substrate) on rumen degradability using in situ method at incubation times of 0, 2, 4, 6, 12, 24, 48, and 72 h according to a Completely randomized design. The results revealed that the highest yeast and LAB population culture in fermented milk was found at 72 h-post cultivation. From in situ study, the soluble fractions at time zero (a), potential degradability (a+b) and effective degradability of dry matter (EDDM) linearly (p<0.01) increased with the increasing supplemental levels and the highest was in the 5% SBMFM supplemented group. However, there was no effect of SBMFM supplement on insoluble degradability fractions (b) and rate of degradation (c). In conclusion, the optimal fermented time for fermented milk with yeast and LAB was at 72 h-post cultivation and supplementation of SBMFM at 5% of total concentrate substrate could improve rumen degradability of beef cattle. However, further research on effect of SBMFM on rumen ecology and production performance in meat and milk should be conducted using in vivo both digestion and feeding trials.
authors.affiliation: Department of Animal Production Technology and Fisheries, Faculty of Agricultural Technology, King Mongkut's Institute of Technology Ladkrabang, Bangkok 10520, Thailand.
authors.forename: S
authors.initials: S
authors.lastname: Polyorach
authors.affiliation: Department of Animal Science, Faculty of Natural Resources, Rajamangala University of Technology-Isan, Phang Khon, Sakon Nakhon 47160, Thailand.
authors.forename: O
authors.initials: O
authors.lastname: Poungchompu
authors.affiliation: Tropical Feed Resources Research and Development Center (TROFREC), Faculty of Agriculture, Khon Kaen University, Muang, Khon Kaen 40002, Thailand.
authors.forename: M
authors.initials: M
authors.lastname: Wanapat
authors.affiliation: Agricultural Unit, Department of Education, National Institute of Education, Phnom Penh 12410, Cambodia.
authors.forename: S
authors.initials: S
authors.lastname: Kang
authors.affiliation: Tropical Feed Resources Research and Development Center (TROFREC), Faculty of Agriculture, Khon Kaen University, Muang, Khon Kaen 40002, Thailand.
authors.forename: A
authors.initials: A
authors.lastname: Cherdthong
keywords: Lactic Acid Bacteria; Nylon Bag Technique; Rumen Degradability; Soybean Meal Fermented Milk; Yeast