Rice straw-based fodder for ruminants

Rice straw has low nutritional value (low protein content and poor digestibility) compared to grasses, thus it cannot support the nutrients required by high-yielding milk cows and buffaloes. There are technologies that have been developed to increase the nutritive value, nutrient digestibility, and utilization of rice straw, such as physical processing, pretreatment using chemicals, and/or biological treatment.

Livestock farming plays a significant role in agricultural development. Aside from being a source of income for the farmers, livestock also contributes to the production of food for the general public. Ruminant animals, such as buffaloes, cattle, sheep, and goats, are considered economically important in the production of meat and milk, among other derived products such as hides, manure as an organic fertilizer or as fuel/biogas for kitchen use by the livestock-farming families. Ruminants can be entirely dependent on crops for their nourishment to achieve normal growth, production, and reproduction.

The dynamics of their rumen ecosystem provide a unique environment for microorganisms to grow and multiply so that these can degrade nutrients, especially fibrous components, from the ingested fodders that eventually are transformed into protein-rich foodstuffs such as meat and milk. However, the efficiency of the animal to utilize and convert nutrients from dietary sources into nutritious food products are dependent mainly on the availability and quality of the fodder being offered to the animal.

The availability of quality forages for feeding ruminants is seasonal. The wet season is a time of feed abundance while the dry season is a period of scarcity. In countries that experience feed scarcity or deficiency of good quality forages, rice straw remains as the practical, abundant and cheap source of fodder for feeding cattle, buffalo, goat, and sheep.

According to FAO, the world produced approximately 2000 million tons of cereal straw annually. More than 200 million tons of rice straw was also produced annually in Southeast Asian countries. The estimated quantity of rice straw production for every hectare of rice farm, the weights of rice grain, and rice straw that can be harvested are the same. In many agricultural countries, rice straw and other agro-industrial by-products are available in large quantities immediately after harvest seasons. These farm byproducts are utilized in many different ways such as fodder for ruminants, mushroom production, fuel (heating, biogas) source, board or paper production, and organic fertilizer production.

Among agricultural byproducts, rice straw is most abundant, low in cost, and a practical source of fodder for ruminants. Its utilization as a livestock feed is limited due to problems in collection, hauling, and storage. Rice straw has low nutritional value (low protein content and poor digestibility) compared to grasses, thus it cannot support the nutrients required by high-yielding milk cows and buffaloes. There are technologies that have been developed to increase the nutritive value, nutrient digestibility, and utilization of rice straw, such as physical processing, pretreatment using chemicals, and/or biological treatment.

However, the adoption of these developed technologies is still low due to farmers’ limited skills and inputs (e.g., farm equipment) and their doubts regarding applicability to the farm situation and the benefits for the animals and livestock producers. To maximize the utilization of rice straw as fodder for ruminants, mechanization is most important to facilitate the collection, hauling, and stacking or processing of all available rice straw from the field.

Read the study:
Aquino, D. et al. (2020). Rice Straw-Based Fodder for Ruminants. In: Gummert, M., Hung, N., Chivenge, P., Douthwaite, B. (eds) Sustainable Rice Straw Management. Springer, Cham.