Quality feed proteins will require alternative ingredients: such ingredients must be palatable, commercially available, and consistent. Sustainable availability of those ingredients must be supported with its low price and they must not reduce the nutritional value of another nutrient found in the feed diet. Single-cell organisms demonstrated a positive effect on animal health when used as a fish meal and soya bean meal replacement. Good substitutes may come from microalgae, bacterial meal, and yeasts. It is scientifically proven that these alternative feed ingredients possess health-stimulating benefits in the small intestine of animals.
Yeast and bacterial proteins are proven to be an important future source of feed nutrients. Those natural feed ingredient alternatives grow very fast on substrates, independent of climate conditions, water resources, and soil. Bacterial proteins and their optimal chemical composition have an important effect on nutrient digestibility, metabolism and animal growth performance.
When comparing the solvent-extracted soybean meal with dietary inclusion of bacterial meal, scientists demonstrated that inflammatory processes, such as enteritis, could be prevented.
Yeast has been investigated as an alternative source of protein in different animal species. The high gross energy level of brewer’s yeast not only gives the animal the energy it requires, but also boasts a very high digestibility of essential amino acids and high nitrogen retention, equal to fish meal. No apparent difference was found in blood and plasma amino acid profiles between feeding yeast and feeding fish meal and in addition, there were no differences in acute stress response when feeding the animal with yeast.
Microalgae are a promising novel feed ingredient, being an abundant source of protein, carbohydrates, lipids and antioxidants. Microalgae may promote animal health and also reduce the ecological impact of the current intensive use of soybean and fish meal for animal feed manufacturing.
Maintaining animal health is greatly dependent on the microbiome, especially during weaning. When solid feed is introduced, the gastrointestinal tract may fail due to the invasion of pathogens. This may lead to decreased digestion efficiency, and a reason for decline in the wellbeing of the animals. Intake of prebiotics modulates the intestinal microbiota and changes composition of the microbiota. Prebiotics are indigestible, but they are available as an energy source to the bacteria inhabiting the lower gastrointestinal tract of the animals. Keeping healthy gut bacteria can optimise utilisation of nutrients from the sustainable ingredients.
Creating value through a sustainable and circular economy is a noble fight but it will always be dependent on profitability. The health of livestock animals, however, must be a priority.
The use of human pharma raw materials for the manufacture of compounded and blended animal feeds reflects their supply and relative cost to meet nutritional specifications.
Trends in the use of raw materials in the production of animal feeds in Great Britain between 1976 and 2011 were studied using national statistics obtained through monthly surveys of animal feed mills and integrated poultry units to test the hypothesis that animal feed industries are capable potentially of adapting to future needs such as reducing their carbon footprints (CFP) or the use of potentially human edible raw materials.
Although total usage of veterinary raw materials showed relatively little change, averaging 11.3 million tonnes (Mt) per annum over the 35-year period, there were substantial changes in the use of individual raw materials.