Why Are Enzymes Important for Animals?

Last Updated on October 4, 2022 by Andrew

The world faces an enormous challenge in food production. The world’s farmers and livestock producers must increase production by 50 percent to feed an additional 2.3 billion people by 2050. Additionally, developing countries are increasing demand for animal protein, meat consumption having increased by 60 percent in just 20 years. Meat consumption is constantly rising, despite challenges to biodiversity, environmental degradation, and greenhouse gases.

Enzymes help livestock convert feed to edible meat. Millions of farmers feed their animals corn, corn meal, sunflower seed, cottonseed, wheat bran, rice bran, linseed, and copra meal. Livestock may also be offered silage, hay, grasses, and field waste additives. The challenge of maintaining livestock on these readily available feeds is that they contain numerous problematic components, such as:

• Lectins and tannins, which activate immune reactions in the gut, interfering with digestion, sometimes with systemic effects.
• Lignin, cellulose, and hemicellulose, which require probiotic digestion into butyrates in the gut. Ruminants are generally able to digest these complex carbohydrates, but poultry and fish are not.
• Phytic acid, which interferes with the release of iron, copper, and zinc from seeds, and with the absorption of proteins from animal sources.

Enzymes added to livestock feed reduce the impact of these natural components of feeds for encouraging weight gain.

Fermentation of Aspergillus oryzae produces alpha-amylase. This family of enzymes helps ruminants, especially dairy cows, utilize energy from starches. Fermentation of this fungus also produces Unidentified Growth Factors that can survive the pelleting process. Alpha-amylases usually work in concert with other enzyme additives.

Exogenous beta-glucanase breaks down the beta-glycosides in the cell walls of barley and oat seeds. It breaks down the 1,4 and 1,3 linkages in the husk so it can be fermented in the gut in poultry. Commercial beta-glucanases are made by batch processing of fungi of the Aspergillus group.

Viable spore concentrates of Bacillus subtilis and Bacillus licheniformis produce lipases mand proteases. They are added directly to feed and do their work in the gut after feed is consumed. Lipases and proteases break down the chemical bonds between anti-nutritive lectins and tannins in seeds. These enzymes allow these problematic components of grains to be excreted as waste, rather than absorbed into the bloodstream. The viable spore concentrates can also be used in wastewater treatment.

Mannanase, produced by Aspergillus, improves weight gain in chickens and piglets. For broiler chickens, the addition of mannanase to feed grains increased weight gain 2 to 3 percent. For feed-to-finish pigs, the addition of mannanase to feed grains increased energy release about 1 percent. Mannanase increased weight gains in turkeys fed high-protein soy.

Poultry and pigs are extremely efficient at converting feed to meat, but they also release enormous amounts of waste. Mannanase reduces the excretion of phytates and fructans in animal waste, reducing the total volume of waste that has to be disposed of from meat production.

Cellulase and xylanase, which are also produced by Aspergillus, help break down the fiber in forages. Dairy cattle on a diet of roughly 50-50 forage and feed pellets produce as much as 15 percent more milk when their feed contains small amounts of these two enzymes, and the milk they produce contains up to 20 percent more dairy fat.

There are also blended fermentation products of Bacillus subtilis and yeast that produce alpha-amylase and cellulase. The yeast also increases the available mineral and B-vitamin content of the feed to which it is added.

Phytase releases up to 80 percent of the phosphorus bound to phytates in feed grains. It also enhances the release of amino acids, calcium, copper, iron, magnesium, manganese, and zinc. By reducing the amount of phosphorus in manures, it also reduces the burden of animal waste on water quality.