It was hypothesized that differences in starch degradability account for observed differences in rumen vaccenic acid (t11-18:1) and milk rumenic acid (RA) concentrations. To test this hypothesis, starch degradability was varied through grain source and by processing. Eight Holstein cows in mid-lactation were assigned to two 4 × 4 Latin squares with four 21-day periods and four diets: dry rolled...

The ruminal degradation of dry matter (DM) and crude protein (CP) and the intestinal availability of CP of four fresh lucerne (Medicago sativa L.) samples, corresponding to a 3rd growing cycle and harvested at 2-week intervals, were determined. Rumen degradability, measured by the nylon bag technique, and rumen outflow rates were determined on three rumen-cannulated wethers. Intestinal digestib...

Mathematical modeling techniques have been applied to study various aspects of the ruminant, such as rumen function, postabsorptive metabolism, and product composition. This review focuses on advances made in modeling rumen fermentation and its associated rumen disorders, and energy and nutrient utilization and excretion with respect to environmental issues. Accurate prediction of fermentation ...

YILDIZ, E. and N. TODOROV, 2014. The comparison of the main protein sources for dairy cows. A review. Bulg. J. Agric. Sci., 20: 428-446 Review of now-a-day knowledge was made for nutritive value and effect on milk yield and composition of the main protein sources – soybean meal (SBM), sunflower meal (SFM), rapeseed (canola) meal (RSM), and dried distillers grain with solubles (DDGS) – in diets ...

A new apparatus, named Bang-Bang (BB), which can facilitate the in situ nylon bag measurement of ruminal degradation in beef cattle, is described. The BB is an apparatus specially designed as a replacement of the traditional steel chain or flexible plastic tubes for binding the bags used in the in situ nylon bag (ISNB) method. The BB apparatus consists of cylindrical pedestals, sealing clips, n...

Most of the P in oilseed meal is in the form of phytate P, and phytate forms complexes with protein. Phytate P has been considered to be absorbed easily in ruminants because of phytate degradation in the rumen. Treatment of oilseed meals with formaldehyde improves the nutritional value of protein through suppressing its ruminal degradation. The present experiment was conducted to study the effe...

Untreated wheat straw (UWS) or ammoniated wheat straw without (AWS) or with (AWSP) a supplement of potato protein of a low rumen degradability was fed to three steers according to a 3 x 3 Latin square design. All rations were supplemented with sugar-beet pulp and minerals. Voluntary organic matter intake (OMI, g/kg0.75 per d) was 67.8, 76.0 and 80.1 for whole rations (51.1, 59.7 and 59.2 for st...