Wheat straw contains a high amount of lignin, hindering the action of cellulase and hemicellulase enzymes, leading to difficulties in nutrient absorption by animals from straw feed. However, currently, the biological treatment of straw relies primarily on fungal degradation and cannot be directly utilized for the preparation of livestock feed. This study focuses on enzymatic co-fermentation of wheat straw to produce high-protein, low-cellulose biological feed, integrating lignin degradation with feed manufacturing, thereby simplifying the feed production process. After the optimization using Box-Behnken Design for the feed formulation, with a glucose oxidase addition of 2.46%, laccase addition of 3.4%, and malonic acid addition of 0.6%, the wheat straw feed prepared in this experiment exhibited a true protein content of 9.35%. This represented a fourfold increase compared to the non-fermented state, and the lignocellulose degradation rate of wheat straw reached 45.42%. These results not only highlight the substantial enhancement in protein content but also underscore the significant advancement in lignocellulose breakdown. This formulation significantly enhanced the palatability and nutritional value of the straw feed, contributing to the industrial development of straw feed.

Normally, proper fermentation can be an efficient and widely used method to improve feed quality in animal rearing; however, the studies on crustaceans, especially Eriocheir sinensis, remain limited. This study aimed to investigate whether feed fermentation could meliorate dietary nutritional value and benefit E. sinensis rearing. First, non-fermented feed (NFD) and fermented feed (FD) were produced and assessed, respectively. Then, the \"Y\" maze feed choice behavior test (180 times; 30 times, 6 rounds) was conducted to assess the attractiveness of these 2 feeds for crabs. Finally, a total of 80 crabs (44.10 ± 0.80 g) were randomly assigned into 2 groups with 4 replicates, and fed the experimental diets for 8 weeks to evaluate the effects of each feed on growth, antioxidant capacity, meat flavor, and intestinal microbiota. In this study, FD showed higher levels of crude protein (P < 0.01), soluble protein (P < 0.01), amino acids (P < 0.05), lactic acid (P < 0.001), and lower levels of crude fiber (P < 0.05) and antinutritional factors (agglutinin, trypsin inhibitor, glycinin, and β-conglycinin) (P < 0.001) than NFD. Additionally, FD was more attractive to crabs than NFD (P < 0.01) and it stimulated the appetite of crabs more than NFD (P < 0.05). The growth performance, feed efficiency, and digestive enzyme activity of FD-fed crabs were significantly higher than those of NFD-fed crabs (P < 0.05). The electronic sensory measurements and free amino acid profiles revealed that the FD diet had positive impacts on the meat flavor of crabs, particularly in \"sweet\" and \"umami\" tastes. Moreover, the antioxidant capacity of FD-fed crabs was significantly higher than that of NFD-fed crabs (P < 0.05). Fermented feed also affected the diversity and composition of intestinal microflora. The functional prediction of microbial communities showed that crabs fed FD had a better microecological environment in the intestine. In conclusion, the fermentation of aquafeed could be an effective approach to enhance feed quality and therefore benefit E. sinensis rearing.

OBJECTIVE: Fermented feed is an agricultural practice used in many regions of the world to improve the growth performance of farm animals. This study aimed to identify and evaluate the lactic acid bacteria and yeast involved in the production of fermented feed.
RESULTS: We isolated and described two micro-organisms from autochthonous microbiota origin present in a regional feed product, Lactobacillus paracasei IBR07 (Lacticaseibacillus paracasei) and Kazachstania unispora IBR014 (Saccharomyces unisporum). Genome sequence analyses were performed to characterize both micro-organisms. Potential pathways involved in the acid response, tolerance and persistence were predicted in both genomes. Although L. paracasei and K. unispora are considered safe for animal feed, we analysed the presence of virulence factors, antibiotic resistance and pathogenicity islands. Furthermore, the Galleria mellonella model was used to support the safety of both isolates.
CONCLUSIONS: We conclude that IBR07 and IBR014 strains are good candidates to be used as starter cultures for feed fermentation.
CONCLUSIONS: The data presented here will be helpful to explore other biotechnological aspects and constitute a starting point for further studies to establish the consumption benefit of fermented feed in farm animal production.