The microbial populations and fermentation characteristics were compared in the rumina of two rumen-cannulated Holstein steers fed untreated rice straw (RS) and concentrate or ammonia-treated rice straw (ARS) and concentrate. The total volatile fatty acid concentrations in the rumina of both steers were significantly higher when they were fed ARS than when fed RS. The molar proportion of butyric acid when ARS was fed increased significantly, compared with the periods when was fed RS. The population density of protozoa varied only insignificantly with RS or ARS diets. But Dasytricha spp. increased with RS and Entodinium spp. increased with ARS. The viable counts of cellulolytic bacteria were higher with ARS than with RS. The viable counts of sulfate reducing bacteria were lower with ARS, compared with the RS diet. Feeding ARS increased the viable bacterial populations such as Eubacterium spp., Fibrobacter succinogenes, Ruminococcus albus, and Succinivibrio spp. But Bacteroides spp. and Butyrivibrio spp. were dominant when RS was fed.Various physical and chemical treatments of low-quality roughages to improve their nutritive values for ruminants have been tried (11,21). Such physical treatments as grinding, milling and chopping have increased the intake of roughages, but has not improved their nutritive value. Moreover, these treatments had the disadvantage of high costs. On the other hand, chemical treatment with calcium hydroxide, sodium hydroxide or ammonia has been tried to improve their nutritive values and to avoid spoilage during storage. Of the treatments with alkali, the ammonia treatment has the advantages of being relatively inexpensive, simply applied on the farm, and it increases the digestibility and the nitrogen content of the herbage. The

This study was conducted to investigate the nutritive values of two peanut by-products, nonstandardized whole peanuts and peanut skins, along with their effects on microbial growth and fermentation in the rumen, their roughage values, and their antioxidative activities by a digestion trial using four goats. The experimental rations were alfalfa haycube (basal ration), 85% alfalfa with 15% whole peanuts, and 70% alfalfa with 15% whole peanuts and 15% peanut skins. The ether extracts and crude protein in whole peanuts were 47% and 27% on a dry matter basis (DM) both with over 90% of digestibilities, resulting in total digestive nutrients (TDN) of 140%. Peanut skins also had a high energy value with 91% of TDN. Ruminal concentrations of total volatile fatty acids (VFA) and acetic acid decreased in the rations containing the peanut by-products, but the NDF digestibility and ruminal microbial protein estimated from urinary purines was not altered by feeding the peanut by-products. Plasma oxidative stress maker, malondialdehyde, tended to be lower when peanut skins were supplemented. Whole peanuts and peanut skins could be used as high-energy and high-protein diets for ruminants, and peanut skins would be expected as a feed having antioxidant functions.

Table 1.Ingredient and nutrient composition of Low by-product (LB), Medium by-product (MB), High by-product (HB) diets 1) Trace minerals (contained 0.44% Fe, 0.35% Cu, 0.46% Zn, 0.33% Mn, 0.005% Co, 0.13% Mg, 0.04% I) and vitamin A, D, E (contained 2,816IU/g vitamin A, 264 mixture.2) NFC=100-(CP+EE+NDF+Ash). Levels of rolled maize, soybean meal and wheat bran in early lactating dairy cows diets were partially replaced by tofu cake, brewers grain and full-fat rice bran, and their effects were studied. Sixty-eight multiparous Holstein cows were used in an experiment in a randomized block design to investigate the effects of the diets on ruminal fermentation characteristics, digestion, plasma composition and milk production. Three diets LB (low), MB (medium) and HB (high) were prepared using different levels of by-products. The cows were divided into three groups, A (n=24), B (22) and C (22), and each group was fed one of three treatment diets as total mixed rations for 15 weeks after calving.Results showed that the by-products level did not affect the dry matter intake of cows. Increasing by-products level in diet increased gross energy content but decreased total tract apparent energy digestibility of the diet. Therefore, by-products level did not affect the digestible energy intake. Milk yield was lower (P<0.05) for HB than LB diet (36.6 vs 40.8kg/d).Milk fat % was higher (P<0.05) for HB or MB than LB diet. However, production of 4% fat-corrected milk tended (P<0.10) to be higher for LB than HB diet (38.0 vs 35.5kg/d). These results suggested that replacement of rolled maize, soybean meal and wheat bran with tofu cake, brewers grain and full-fat rice bran should be kept less than 10% of the total diet.

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