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molasses-multi-nutrient block (Vu et al. 1999; Wanapat et al. 1999; Akter et al.
2004); these significantly increase the cow’s milk production.
7.4.2 Effects of Biological Treatment of Rice Straw
Zadrazil (1977) identified three species of fungi based on substrate preference and
type of enzymes they secrete for the degradation rice straw cell walls. The first
group has cellulolytic and hemicellulolytic activities of which they act on cellulose
and hemicellulose. The second group of fungi preferentially acts on the lignin content while the third group of fungi decomposes cellulose, hemicellulose, and lignin
simultaneously. The second group of fungi is the most recommended for rice straw
treatment because of its peculiarity to break and degrade structural carbohydrates
present in rice straw. It is suggested that screening new fungal strains is essential
with desired characteristics to efficiently improve the nutritive and feeding value of
rice straw.
Zayed (2018) evaluated different parameters for the improvement of the nutritional value of rice straw. During his evaluation, he used moist straw, soaked straw
for 24 h without pasteurization, and soaked straw for 24 h with pasteurization at
100 °C for 1 h. The preprocessed rice straw samples were inoculated having three
combinations of microbial inoculants. He also observed that moistened rice straw
had the highest organic matter reduction at 74.21% if inoculated with Azotobacter
chroococcum and Saccharomyces cerevisiae. Additionally, if inoculated with
Azospirillum brasilense and Saccharomyces cerevisiae, significant reduction in
crude fiber at 27.54%; neutral detergent fiber at 55.39%; and 42.47% acid detergent
fiber can be observed. For rice straw soaked for 24 h and inoculated with Azospirillum
brasilense and Bacillus megaterium, a significant increase in crude protein at
13.71% was observed. Zayed (2018) further concluded that interaction between
microbial treatment and physical pretreatments of rice straw shows a significant
decrease in organic matter, crude fiber, neutral detergent fiber, and acid detergent
fiber as well as a significant increase in crude protein compared to the control.
7.5 Limitations of Rice Straw Utilization
Several factors were identified that limit the utilization of straw as animal fodder.
These include poor digestibility, low animal intake, and very low protein content.
Technologies to overcome the identified factors have been developed for pretreatment of straw before feeding to animals. However, its adoptability varies according
to the capacity and capability of the farmers or its practicality including health and
environmental concerns when used by the farmers.
In physical treatment of straw, the limitation is mainly on grinding of the straw
into smaller particle size. The positive effect of reduced particle size is that it
D. Aquino et al.
molasses-multi-nutrient block (Vu et al. 1999; Wanapat et al. 1999; Akter et al.
2004); these significantly increase the cow’s milk production.
7.4.2 Effects of Biological Treatment of Rice Straw
Zadrazil (1977) identified three species of fungi based on substrate preference and
type of enzymes they secrete for the degradation rice straw cell walls. The first
group has cellulolytic and hemicellulolytic activities of which they act on cellulose
and hemicellulose. The second group of fungi preferentially acts on the lignin content while the third group of fungi decomposes cellulose, hemicellulose, and lignin
simultaneously. The second group of fungi is the most recommended for rice straw
treatment because of its peculiarity to break and degrade structural carbohydrates
present in rice straw. It is suggested that screening new fungal strains is essential
with desired characteristics to efficiently improve the nutritive and feeding value of
rice straw.
Zayed (2018) evaluated different parameters for the improvement of the nutritional value of rice straw. During his evaluation, he used moist straw, soaked straw
for 24 h without pasteurization, and soaked straw for 24 h with pasteurization at
100 °C for 1 h. The preprocessed rice straw samples were inoculated having three
combinations of microbial inoculants. He also observed that moistened rice straw
had the highest organic matter reduction at 74.21% if inoculated with Azotobacter
chroococcum and Saccharomyces cerevisiae. Additionally, if inoculated with
Azospirillum brasilense and Saccharomyces cerevisiae, significant reduction in
crude fiber at 27.54%; neutral detergent fiber at 55.39%; and 42.47% acid detergent
fiber can be observed. For rice straw soaked for 24 h and inoculated with Azospirillum
brasilense and Bacillus megaterium, a significant increase in crude protein at
13.71% was observed. Zayed (2018) further concluded that interaction between
microbial treatment and physical pretreatments of rice straw shows a significant
decrease in organic matter, crude fiber, neutral detergent fiber, and acid detergent
fiber as well as a significant increase in crude protein compared to the control.
7.5 Limitations of Rice Straw Utilization
Several factors were identified that limit the utilization of straw as animal fodder.
These include poor digestibility, low animal intake, and very low protein content.
Technologies to overcome the identified factors have been developed for pretreatment of straw before feeding to animals. However, its adoptability varies according
to the capacity and capability of the farmers or its practicality including health and
environmental concerns when used by the farmers.
In physical treatment of straw, the limitation is mainly on grinding of the straw
into smaller particle size. The positive effect of reduced particle size is that it
D. Aquino et al.