农业科学学报(英文版)
農業科學學報(英文版)
농업과학학보(영문판)
NONGYEKEXUEXUEBAO
2015年
3期
550-560
,共11页
anaerobic rumen fungi%bacterial DFM%direct-fed microbials%probiotics%rumen
To keep the concept of a safe food supply to the consumers, animal feed industries world over are showing an increasing interest in the direct-fed microbials (DFM) for improved animal performance in terms of growth or productivity. This becomes al the more essential in a situation, where a number of the residues of antibiotics and/or other growth stimulants reach in milk and meat with a number of associated potential risks for the consumers. Hence, in the absence of growth stimulants, a positive manipulation of the rumen microbial ecosystem to enhance the feedstuff utilization for improved production ef-ifciency by ruminants has become of much interest to the researchers and entrepreneurs. A few genera of live microbes (i.e., bacteria, fungi and yeasts in different types of formulations from paste to powder) are infrequently used as DFM for the domestic ruminants. These DFM products are live microbial feed supplements containing natural y occurring microbes in the rumen. Among different DFM possibilities, anaerobic rumen fungi (ARF) based additives have been found to improve ruminant productivity consistently during feeding trials. Administration of ARF during the few trials conducted, led to the increased weight gain, milk production, and total tract digestibility of feed components in ruminants. Anaerobic fungi in the rumen display very strong cel-wal degrading cel ulolytic and xylanolytic activities through rhizoid development, resulting in the physical disruption of feed structure paving the way for bacterial action. Signiifcant improvements in the ifber digestibil-ity were found to coincide with increases in ARF in the rumen indicating their role. Most of the researches based on DFM have indicated a positive response in nutrient digestion and methane reducing potential during in vivo and/or in vitro sup-plementation of ARF as DFM. Therefore, DFM especial y ARF wil gain popularity but it is necessary that al the strains are thoroughly studied for their beneifcial properties to have a conifrmed‘general y regarded as safe’ status for ruminants.