PORTO, PORTUGAL and STUTTGART, GERMANY — Recent research from scientists in Portugal and Germany, published in Frontiers in Veterinary Science, in-depth on two novel protein sources for use in pet food. According to the results of the study, squid meal and shrimp hydrolyzate show promise as sources of protein in dog food.
With the global pet population on the rise, sustainability and environmental concerns continue to remain for consumers. Protein-rich marine byproducts can help address these concerns by reducing negative environmental impacts, reducing waste and improving economic efficiency.
Research has examined two marine byproducts, squid meal and shrimp hydrolysate, as sources of protein in dog foods. The squid meal was supplied by Madrid-based Inproquisa and is a byproduct from the canning industry. Shrimp hydrolyzate was supplied by Elven, France-based Symrise Aqua Feed. Both byproducts are used in dry powder formats.
During the study, 12 Beagles were fed standard commercial dog food (basal diet), a diet made with squid meal, or a diet made with shrimp hydrolysate. Additionally, two in vivo digestibility trials were conducted in which dogs were fed different levels of inclusion of 50, 100 and 150 grams per kilogram of squid meal or shrimp hydrolyzate in three periods, consisting of 10 days each.
The researchers evaluated apparent total tract digestibility (ATTD), metabolizable energy content, fecal characteristics, metabolites and microbiota. Squid meal and shrimp hydrolyzate protein sources showed higher protein and methionine content compared to traditional ingredients used in a dog food formula, and shrimp showed higher antioxidant activity compared to squid meal.
“The initial approach and taste were not affected by the inclusion of protein sources, but the animals showed a preference for the basal diet,” the researchers wrote. “Effects on nutrient intake reflect the chemical composition of the diets, and fecal output and characteristics were not affected by increasing levels of inclusion of both protein sources.”
Additionally, the researchers noted that squid and shrimp byproducts resulted in higher dry matter ATTD for most nutrients and energy compared to the traditional diet, suggesting that novel protein sources that it may be suitable for highly soluble formulas. Dietary inclusion of squid was found to decrease butyrate concentration, whereas shrimp increased all volatile fatty acids except butyrate.
According to the research, the fecal microbiota remained unaffected by the inclusion of squid meal, however, the shrimp hydrolyzate was found to have a significant effect on anaerobic bacteria. Oscillospiraceae, Firmicutes and Lactobacillus.
Regarding palatability, the researchers found that no food aversion was observed for any of the diets. However, palatability was negatively affected by the inclusion of 150 grams per kilogram of shrimp hydrolyzate or squid meal.
“This result was unexpected because both squid meal and shrimp hydrolyzate showed high levels of glutamic and aspartic acids, two amino acids found in various foods, including seafood, known to -induced umami, a taste that is highly attractive to dogs,” the researchers wrote.
“Overall, the results suggest that squid meal and shrimp hydrolyzate constitute novel and promising protein sources for dog food, but further research is needed to fully assess their functional value,” concluded them.
Read the full study here.
Find more articles related to pet nutrition research.
