Aquaculture ongoing growth requires new efficient, safe, and sustainable protein sources. The use of plant-based protein sources, especially from soy, as partial replacement for fish meal is common but limited due to the presence of antinutrients. Palbio is a high-quality, sustainable, protein obtained from porcine intestinal mucosa as a byproduct of the heparin manufacturing process following a circular economy approach. It contains bioactive peptides and leads to health benefits in animal species, especially in swine. Its use in aquaculture might allow lower inclusion levels of plant-based protein sources. The essential amino acids profile is a key parameter to evaluate the suitability of a protein source for animal feed, and protein quality can be estimated by calculating the contribution of each amino acid to the ideal pattern. We evaluated the suitability of Palbio by analyzing its amino acid profile and comparing it with that of soy and with the requirements of Atlantic salmon (Salmo salar) and pig (Sus scrofa ) using the ideal protein approach.
The amino acid content in three different Palbio HP industrial batches (20/0001, 21/0001, 21/0072; Bioiberica SAU, Palafolls, Spain) was measured with high-performance liquid chromatography with fluorescence detection (HPLC/FLD). Pig and salmon muscle amino acid profile were obtained from Bahelka et al., 2020 and Wilson & Cowey et al., 1985, respectively; soybean meal data from AmiPig (2000); and n utritional requirements from publicly available defined nutritional requirements (NRC of swine 2012, and NRC of fish and shrimp 2011).
Palbio HP results are shown in Table 1, while Figure 1 depicts a comparison and degree of overlap between the different amino acid profiles and nutritional requirements. Our analyses showed a high degree of overlap between Palbio HP and salmon muscle and nutritional requirements, and similar to those of pig. Conversely, soybean meal, as a reference plant-based protein sourc e, shows a lower degree of overlap representing lower theoretical nutritional adequacy for salmon diets.
Given the suitability and the reported health benefits of Palbio as protein source for pigs and based on the herein reported suitability also for salmon, Palbio c ould serve as an adequate protein source to maximize growth and feed utilization in salmon and provide health benefits as well.