No abstract

The aim of this study was to compare voluntary feed intake, nutrient digestibility, and rumen fermentation of Thai native and Thai native x Lowline Angus crossbred beef cattle fed with different diets. Three different diets consisting of ad libitum rice straw (RS), ad libitum RS supplemented with 0.5% body weight (BW) concentrate (RS+C), and ad libitum Pangola grass hay (PH). The experiment was conducted as 3 × 3 replicated Latin square design with a factorial arrangement of dietary treatment and breed. It was found that Thai native and Thai native x Lowline Angus crossbred beef cattle had comparable roughage intake, BW change, nutrient digestibility, and all parameters from rumen fluid. Cattle fed with different type of feed showed similar roughage intake, BW change, and number of protozoa and fungal zoospore in rumen fluid. However, nutrient intake and digestibility of cattle supplemented with concentrate were higher than those fed the roughage alone. Accordingly, concentration of total volatile fatty acid and proportion of propionic acid in rumen fluid of cattle received concentrate was higher than cattle fed only RS (P < .05) but not for cattle fed with PH. Moreover, the PH-fed group had a higher ammonia concentration in rumen fluid than did the RS-fed group (P < .05). Therefore, the two breeds of beef cattle showed comparable feed response while supplementation of concentrate at 0.50% BW was a useful alternative feeding pattern.ARTICLE HISTORY