The U.S. slaughter industry produces blood co-products that may be used in diets for nursery pigs because of the high concentration and quality of protein they contain. The quality of protein in blood products can differ based on the processing techniques used.  In particular, products which are heated to too high a temperature during processing can sustain heat damage to amino acids due to the Maillard reaction. Lysine is particularly susceptible to heat damage.

An experiment was performed to determine the comparative amino acid digestibility in five different blood products fed to weanling pigs. Three are spray-dried products, which are dried quickly at temperatures of up to 225˚C. Spray-dried animal blood (SDAB) is manufactured from whole blood containing an anticoagulant. Spray-dried plasma protein (SDPP) is manufactured from blood which has had the plasma separated out by centrifugation. Spray-dried blood cells (SDBC) are the red blood cells left after plasma separation. In addition to the spray-dried products, two sources of blood meal were tested – one from an avian source (avian blood meal, or ABM) and one from a porcine source (porcine blood meal, or PBM). These blood meals were dried using drum driers instead of spraydriers.

Animal proteins such as milk products, blood products, fish meal, chicken meal (CM), and poultry by-product meal (PBM) are usually used as amino acid sources in diets for weanling pigs because the nutrients in these ingredients are highly digestible and because they do not contain the anti-nutritional factors that are present in conventional soybean meal. Due to the cost of animal protein sources, other alternatives have been investigated. One alternative is soybean meal which has been fermented to destroy antinutritional factors and increase protein digestibility. Fermented soybean meal (FSBM) has been shown to be able to replace milk, blood proteins, and fish meal in diets fed to weanling pigs. However, there are no data on whether or not fermented soybean meal can replace chicken meal and poultry by-product meal. An experiment was, therefore, performed to test the hypothesis that fermented soybean meal can replace chicken meal and poultry by-product meal in diets fed to weanling pigs without negatively affecting growth performance.

Lemna Protein Concentrate is derived from the leaves of duckweed, one of several rapidly-growing aquatic plants of the genus Lemna. Duckweed has a number of advantages as a protein source. It is relatively inexpensive to produce and requires less growing area and fewer inputs than other plant protein sources such as soybean products. It also contains relatively little fiber, making it a highly digestible feed ingredient.

An experiment was conducted to determine the digestibility of amino acids and crude protein in Lemna Protein Concentrate fed to weanling pigs and to compare these values to digestibility values obtained for soybean meal and fish meal.

Soybean meal fed to pigs undergoes heat treatment to destroy trypsin inhibitors and other antinutritional factors that impair the digestion of protein and thus reduce performance. However, heat treatment can damage nutrients as well. In particular, the Maillard reaction reduces amino acid digestibility by combining amino acids with sugars to produce biologically unavailable compounds.

An experiment was conducted to determine the digestibility of amino acids in pigs fed soybean meal that had been heat treated in varying ways and for varying times. Conventional soybean meal was divided into four batches. One batch was not heated; one was autoclaved at 125°C for 15 minutes; one was autoclaved at 125°C for 30 minutes; and the last one was oven dried at 125°C for 30 minutes. Ten growing barrows were fed a total of five different diets. The experimental diets contained 40% each of the four different soybean meals being tested. An N-free diet was also formulated and fed to measure the basal endogenous loss of protein and amino acids.

Meat and bone meal (MBM) is a product of the rendering industry composed primarily of the offal and bones of slaughtered livestock, fat from unmarketable animal tissues, unsellable retail meat products, and whole condemned carcasses (excluding hair, blood, hooves, horns, and contents of the gastrointestinal tract).  MBM is traditionally used as an animal protein source in swine diets, but because of its high concentrations of calcium and phosphorus, it can also replace inorganic phosphates in swine diets.

The proportions of soft tissue and bone in different sources of MBM can vary widely. Because mineral digestibility differs in bone and soft tissue, the variation in composition of MBM sources leads to a variation in mineral digestibility values.

An experiment was conducted to 1) determine the apparent (ATTD) and standardized (STTD) total tract digestibility of phosphorus and the ATTD of calcium in 8 different sources of MBM,  2) estimate variation among MBM sources, and 3) develop equations to predict the concentrations of digestible phosphorus and calcium in MBM.

Soybean meal is a rich source of digestible amino acids for pigs. However, soybeans contain antinutritional factors such as antigenic proteins, oligosaccharides, lectins, and trypsin inhibitors that make soybeans and conventional soybean meal unsuitable for feeding to weanling pigs in great quantities. Therefore, animal protein is usually included in starter diets for pigs. Because soy protein is less expensive than the animal protein, strategies to reduce the antinutritional factors in soy products have been explored. Fermentation of soybean meal with bacteria such as Aspergillus oryzae and Lactobacillus subtilis eliminates many antinutritional factors, and studies have shown that fermented soybean meal is well-tolerated by weanling pigs. However, there is a lack of data on the digestibility of energy and amino acids in fermented soybean meal. Two experiments were, therefore, conducted to measure the concentration of DE and ME and the digestibility of amino acids in fermented soybean meal and to compare these values to values obtained in conventional soybean meal and fish meal.

Dried Fermentation Biomass (Ajinomoto Heartland LLC) is a co-product of the commercial production of lysine. Peptone 50 and PEP2+ (TechMix LLC) are co-products of heparin production by the human pharmaceutical industry. The latter two are produced from hydrolyzed pig intestines co-dried with a vegetable protein (Peptone 50) or enzymatically processed vegetable proteins (PEP2+). These co-products are being investigated as possible cost-effective replacements for fish meal in weanling pig diets.

An experiment was performed to measure the apparent and standardized ileal digestibility of CP and amino acids by weanling pigs in Dried Fermentation Biomass, Peptone 50, and PEP2+, respectively, and to compare these values to digestibility values obtained in fish meal.

Corn contains approximately 0.26% phosphorus, but most of this phosphorus is bound to phytic acid, or phytate, and thus is not bioavailable to pigs because they lack the enzyme phytase. Corn-based diets can be supplemented with inorganic phosphorus to help meet pigs' phosphorus needs; however, rising costs of inorganic phosphorus makes this approach increasingly uneconomical. Helping pigs digest more of the phosphorus that naturally occurs in the diet could provide a cost-effective alternative to inorganic phosphorus supplementation while also helping to reduce the environmental burden of excreted phosphorus. An experiment was conducted to determine how adding graded levels of microbial phytase affected the standardized total tract digestibility (STTD) of phosphorus in corn and corn co-products. From these data, regression equations were developed to predict the response to adding different levels of phytase to each ingredient.

Copra and palm kernel co-products are commonly fed to ruminant animals in some parts of the world. However, very limited research has been reported on the use of these ingredients in swine diets. No values are listed in the NRC (1998) for copra expellers, palm kernel expellers, or palm kernel meal.