The use of enzymes and nuclear technologies to improve the utilization of fibrous feeds and reduce greenhouse gas emission from livestock (D3.10.27)

Rationale and background:

Livestock production in many developing countries is constrained because of poor nutrition. Cereal crops (maize, rice, wheat, sorghum etc) straw and stover are the main source of feed for ruminant animals especially during the dry season and/or winter although it is well recognized that these straws and stover have poor nutritional value because of their low energy and nitrogen and high fibre content. There is also a lack of and/or limited use of concentrate feeds because the farmers can hardly afford them. The feed shortage problem is being exacerbated by the decreasing availability of arable land due to the rapidly increasing human population, soil degradation, urbanization and effects of climatic variations and global warming. Moreover, as the world gets hotter and drier, glaciers will melt, and the amount of arable land will shrink even further.

Highly fibrous diets not only decrease the feed-use efficiency, but also increase methane production in ruminants. The increased concentration of methane (a potent greenhouse gas) in the troposphere has been implicated in global warming. Methane is produced as part of normal digestive processes in ruminant animals. During digestion, microbes resident in an animal’s digestive system ferment food consumed by the animal in a process referred to as enteric fermentation, which produces methane as a by-product, which is exhaled, or eructated by the animal. The amount of methane produced and emitted by an individual animal depends primarily upon the animal’s digestive system, and the amount and type of feed it consumes. Methane production from ruminants fed highly fibrous diets such as the straws and stover is higher than those from animals fed better quality forages. Furthermore, methane production is negatively correlated with energy utilization and it can range from two to 12% of the gross energy intake, thus, reduction of methane production through the use of enzymes and rechanneling the hydrogen to short-chain fatty acids and microbial mass is desirable. Reducing methane emissions from ruminants therefore has implications not only for efficient animal production but also for global environmental protection.

Overall objectives:

The objective of this CRP is to improve the efficiency of using locally available feed resources for improved livestock productivity while protecting the environment.

Specific research objectives:

  • To determine the effects of supplementing livestock diets with enzymes on (i) fibre degradation in vitro, in situ and in vivo, (ii) feed intake and digestibility, (iii) ruminal fermentation and microbial protein synthesis and (iv) on milk production and composition and/or growth performance.
  • To determine the mode of action, the critical enzymic activities and application method and rates needed to elicit the desired response.
  • To determine the effects of supplementing livestock diets with enzymes on animal performance, enteric methane production and cost-benefit analysis.
  • To build capacity in developing countries on the use of nuclear and related technologies to improve livestock productivity and to create opportunities for research collaboration internationally.

Expected outputs:

  • Increased knowledge on how enzyme improve fibre utilization, optimal enzyme activity, application rate and application method rates to improve the efficiency of utilizing fibrous feeds to improve livestock production and reduce enteric methane production and promote self-reliance.
  • Increased capacity of National Agriculture Research Systems to integrate molecular techniques into research programmes on ruminant nutrition and/or conduct inter-disciplinary research.
  • Published and disseminated research results (TECDOC, Special Issue of a Journal, etc).

Implementation procedure:

Organisation of the CRP network

Ten research contracts will be awarded to Member States submitting appropriate research proposals. Institutions interested in participating on the CRP should be (i) linked with national livestock development authorities and be engaged in programmes of national importance in animal production; (ii) have some level of local and/or external financial support; (iii) have access to well established animal nutrition laboratories with basic expertise in molecular technologies; (iv) have transportation capabilities for field experimentation, data and sample collection and (v) have computerized data management and analysis capabilities. Furthermore, the project will be integrated into on-going development activities and will work closely with farmers and farmers’ organizations. Four Research Agreements will be awarded to institutes that have expertise in specific areas of importance and interest to the CRP. Two technical contracts will be awarded to characterize the mode of action of the feed additive, optimal level of application and the most cost effective application method.

First Research Coordination Meeting (RCM)

The first RCM will be held in the first quarter of 2011. Research Contract holders will present an overview of the livestock production systems in their countries, main constraints and the proposed research. Agreement holders will present state-of-the-art laboratory techniques, methodologies, and available resources for identifying, evaluating, and monitoring effects of enzymes on fibre utilization and animal productivity. The RCM will focus on (i) evaluating, discussing and finalizing the details of standardized work plans and protocols of work for the first 18 months, and (ii) general activities for the whole life of the CRP including allocation of research tasks and management scheme for each set of tasks to allow reporting and formulate coordination plans.

First 18 months of Programme of Work

In vitro screening of commercial fibrolytic enzymes to identify 3 to 4 best-bet candidates for further evaluation in animal trials including mode of action of the enzyme, optimal level of application and the most cost effective application method.

Second RCM

The second RCM will be held in the first quarter of 2013 to review the results from the several studies conducted during the first 18 months of the CRP which will form the basis for revising and updating the work plans and activities to be undertaken during the second 36 months of the CRP within a time schedule for each research contract.

Second 36 month of Programme of Work

In vivo evaluation of best-bet candidate fibrolytic enzymes on ruminal fermentation, microbial protein synthesis, microbial diversity and populations, methane production, nutrient intake, diet digestibility, and milk production and composition.

Third and final RCM

The final RCM will be held in 2015 to review the results of the CRP, and to make recommendations for future directions, strategies, and nutritional activities related to the improvement of animal productivity in developing countries. Final reports will be peer-reviewed, and prepared for publication as an Agency TECDOC or Special Issue or Supplement of a journal in 2015.


[Download pdf]


  • Report of the First RCM, 7 to 11 February 2011, Lethbridge, Alberta, Canada. [Download pdf]

Project Officer:

N. Odongo