On this page, we offer the following suggestions to improve animal nutrition and feed efficiency and to reduce methane (CH4) emissions:
Click a link in the list above to jump to that topic on this page.
Advancing the production efficiency of livestock feeds should lower feed costs, while reducing the amount of biological waste and enteric fermentation produced by cattle and hogs. Improving animal nutrition and feed efficiency will also cut greenhouse gas emissions.
Enteric fermentation is the microbial breakdown of feed components in ruminants, causing methane (CH4) production in the intestines.(1) The amount of gas produced by animals can be strongly influenced by the quality of foodstuffs ingested. Up to 12 percent of feed energy can be converted into CH4 gas when low quality fed is used in rations.(2)
A better quality feed, such as grain or feed with low fibre (fresh grass, alfalfa), will digest easier, increase feed efficiency and lower CH4 and waste production.(3) Research in Manitoba found that there were 50 percent less CH4 emissions from grazing steers with access to high quality pastures.(4)
Low fibre diets were also shown to lower CH4 emissions in a swine dietary study in Denmark.(5) The loss of feed energy into excrement or GHGs represents lost profit for farmers since the energy is not being converted into animal protein.
Improving production efficiency
Any practice that reduces the number of livestock needed to meet demand will reduce overall GHG emissions. Such steps include accelerated growth, improved reproduction, selective breeding(6) and improved herd health. Improving animal performance and genetics can lower CH4 emissions from dairy and beef cattle by 3 percent. Emissions per pound live weight gain are reduced as production efficiencies increase.(7)
Allowing animals to graze and harvest their own forage throughout the year can also reduce production costs and GHG emissions. Options include season-long grazing, swath grazing and bale grazing.
Improving feed efficiency
The easiest way to improve livestock feed efficiency is to avoid overfeeding animals. Feeding excessive nutrients results in more nutrients excreted in manure. In cattle, excessive nutrient intake increases rumen CH4 emissions and wastes money on additional feed.
Formulating diets based on the physical requirements of the animal will prevent overfeeding and ensure the animal is accessing the proper amounts of vitamins, minerals, protein and fibre. Animal nutritionists can analyze the nutrient content of feed and formulate diets with an ideal mix of protein, minerals and other essential nutrients.(8)
Lowering GHG emissions due to poor feed efficiency can also be done by grinding or pelleting feed to lower the amount of digestion performed by the animal. Research shows that between 20 and 40 percent of total CH4 emissions were reduced when feed size was decreased.
Maintaining proper animal health will also ensure that the animal is prime condition for digesting and absorbing nutrients and reduce likelihood of feed energy loss.(9)
Adding fats or vegetable oils to grain diets can improve feed efficiency by reducing the amount of feed that is fermented. However, no more than 6 percent of a daily ration can be fat, otherwise the digestion of fibre is compromised. A study in Alberta found that CH4 emissions were reduced by 33 percent when 4 percent canola oil was added to a feedlot diet.(10)
Improving feed efficiencies in poultry rations can be controlled with enzymes to enhance nutrient retention and lower nutrient excretion. Enzymes such as amylase and B-glucanase have been found to lower methane emissions in studies.(11)
Feeding a balanced diet of high quality feeds
Feeding animals a balanced diet of high quality feeds is important for both livestock health and feed efficiency. Farmers should make sure that animals are fed a balanced ration with a good mixture of protein, energy, minerals and vitamins. The type and quantity of feed stuffs in a diet will vary depending on species, breed, body weight, production stage, age and reproductive stage.(12)
High fibre diet research showed an improvement in the well-being of animals and digestion and a reduction of stomach ulcers. However, too much dietary fibre can lead to reduced available energy for the animal if no high energy ingredients (animal fat or vegetable oil) are included in the diet. High fibre diets also mean high enteric fermentation and increased methane (CH4) emissions.(13)
Formulating diets based on animal requirement and using a variety of feedstuffs is the best way to lower CH4 emissions without harming livestock performance.
For pigs, diets rich in fat, starch and protein with low fibre are best for lowering CH4 emissions and excrement.
For many cattle producers, testing winter rations for nutrient levels is hard, and many farmers feed whatever is available. Ensuring a varied winter diet of energy, protein, minerals and vitamins for beef cattle will maintain animal health and could cut GHG emissions by 15 percent.(14)
Low quality feeds will produce elevated levels of methane. Limiting straw intake and increasing higher quality feeds in rations will reduce methane emissions. For instance, straw intake could be lowered from 24 pounds (lbs) to 18 lbs and an additional 1 lb of barley added to an 8 lb/day barley ration. A small addition of one pound higher quality feed is all that is needed to replace the lost straw. The daily ration of 18 lbs straw and 9 lbs barley would reduce CH4 emissions without compromising nutrition. While there could be some increase in feed costs, the added benefit of energy and better utilization could outweigh the added cost of grain.(15)
Aiding digestion in swine
Pigs struggle to digest phytate in cereal grains. Adding phytase to the feed can help pigs break down the phytate. Not only does adding phytase reduce phosphorus (P) excretion, it also increases feed use efficiency and decreases nitrogen (N) output in manure. A study at the University of Manitoba found that completely removing inorganic P from pig diets while supplementing phytase improved digestibility and reduced excretion losses.(16)
Reduce dietary protein in swine rations
Although pig diets are highly formulated to supply nutrient at the specific levels needed by the animal, actual nutrient requirements vary between individual pigs. Rations usually oversupply protein, causing an excess of N and C excretion.
Reducing protein levels and including a proper balance of amino acids in the diet is a cost-effective means to reduce GHG emissions from hogs. There will be little impact on performance and little or no cost added to the farmer.(17)
For more information, download our publication “Farming in a Changing Climate in Manitoba – Livestock Edition (2013)“
