The aim of the present study was to investigate the effects of dietary supplementation with different doses of rosmarinic acid (RA) on the growth performance, serum biochemical indices, liver antioxidant activity, and muscle nutritional component of broiler chickens during 1–20 days of age. A total of 1000 1-day-old Cobb 500 white-feathered broilers were divided into five groups. Each group included four replicates and 50 birds per replicate. The control group was the basic fodder group fed with a basal diet. The experimental groups included four levels of RA (100, 200, 300, and 400 mg/kg RA added to the basal diet, respectively). The results showed that a quadratic increase in final body weight (BW) and average daily gain (ADG) and a quadratic decrease in the feed/gain (F/G) ratio were observed with increasing dietary RA levels. At 200 mg/kg RA supplementation, growth performance was significantly improved. Moreover, under this RA treatment, the highest levels of total protein and globulin were detected in the serum, the activities of total superoxide dismutase and catalase in the liver of broilers were significantly increased, and the malondialdehyde content was significantly decreased, indicating a higher antioxidant capacity of the liver when 200 mg/kg RA was added to the basal diet. The flavor of the muscle meat was improved by dietary supplementation with 200 mg/kg RA. Therefore, adding 200 mg/kg of RA to the diet could significantly improve the growth performance of broilers, improve liver antioxidant capacity, and improve muscle quality, etc. The addition of RA to broiler feed as a natural antioxidant has great prospects.

This study aimed to investigate the effects of different defatting methods of black soldier fly (Hermetia illucens) larvae meal (BSFM) on the metabolic energy and nutrient digestibility in laying hens. Sixty young laying hens (Hy-Line W-36) aged 63 days were randomly divided into two groups (G1 and G2), each with five replicates of six hens housed in individual cages. Group G1 was fed 25% pressed black soldier fly meal (BSFMp) and 75% basal diet, and Group G2 was fed 25% extracted black soldier fly meal (BSFMe) and a 75% basal diet. Both diets included 5 g/kg chromium oxide as an external marker. A 7-day preliminary trial was followed by a 4-day experimental period. The results indicate that pressing and extracting significantly affected the digestibility of crude fat and total energy in BSFM, with BSFMp showing significantly higher crude fat digestibility than BSFMe. Similarly, total energy digestibility was also significantly higher in BSFMp. However, there were no significant differences in dry matter, organic matter, and crude protein digestibility between the two processing methods. The apparent metabolic energy values of BSFMp and BSFMe were 16.34 and 12.41 MJ/kg, respectively, showing a significant difference. The nitrogen-corrected metabolic energy values were 15.89 MJ/kg in BSFMp and 11.93 MJ/kg in BSFMe, indicating a highly significant difference. The digestibility of arginine and leucine in BSFMp was significantly higher than in BSFMe, while differences in lysine, cystine, threonine, tryptophan, and isoleucine were not significant. In conclusion, both defatting methods of BSFM had no adverse effects on the metabolic energy and nutrient digestibility in young laying hens, but BSFMp demonstrated better effects on the digestibility of metabolic energy and nutrients in the feed for young laying hens.

Black soldier fly larvae (BSFL) convert kitchen waste into high-quality insect feed. However, the optimal amount of auxiliary materials needed to improve the physical and chemical properties of kitchen waste and enhance BSFL bioconversion efficiency remains unresolved. In this study, maize stover and BSFL frass were added to kitchen waste (in groups G2 and G3, respectively) to explore their effects on the growth performance and bioconversion efficiency of BSFL. The group with only kitchen waste, without the addition of maize stover or BSF frass, was used as the control group and labeled as G1. On the 5th day, the body length of the BSFL in the G2 group was significantly greater than that in G1 and G3 (p < 0.05). The dry matter weight loss rate in the G3 group was significantly lower compared to that of G1 and G2 (p < 0.05), and the feed conversion rate (FCR) of G1 was significantly lower than that of G2 and G3 (p < 0.01). In summary, adding maize stover and BSFL frass increased BSFL feed intake and improved body weight gain. However, these additives did not significantly enhance BSFL bioconversion efficiency. The organic matter in maize stover and BSFL frass was utilized by the BSFL, and the heavy metal levels in each group of BSFL did not exceed standard limits.

This study investigated the effects of 3% (G3), 6% (G6), and 9% (G9) dietary defatted black soldier fly larvae (BSFL) meal on 288 Hy-Line Brown laying hens over 210 days. While egg production and weight showed no significant differences (p > 0.05), feed-to-egg ratios increased in higher inclusion groups (G6, G9) versus 0% control (G0) during later phases (p < 0.01). G6 exhibited enhanced eggshell strength versus G0 (p < 0.05), while G3 demonstrated thicker eggshells than all groups (p < 0.05). Serum analysis revealed G3 had superior total antioxidant capacity and lower lipid peroxidation versus G0 and G9 (p < 0.05), along with elevated gonadotropin-releasing hormone levels compared to G9 (p < 0.05). Intestinal morphology remained unaffected across treatments. The 3% BSFL inclusion optimally balanced eggshell quality and antioxidant status under isoenergetic-isoprotein conditions, supporting its viability as a sustainable protein source in poultry diets. Findings advocate BSFL meal as an eco-friendly feed alternative, with 3% identified as the most effective inclusion rate.

Nitrogen pollution in wastewater remains a pressing environmental concern, prompting the need for efficient and sustainable treatment technologies. This study constructs an HN-AD microbial consortium using three pre-screened strains (Delftia tsuruhatensis SDU2, Pseudomonas stutzeri SDU10, Alcaligenes faecalis SDU20) and evaluates its bioaugmentation effects in sequencing batch reactors (SBRs). An orthogonal test optimized the inoculation ratio as 2:3:3 (SDU2:SDU10:SDU20), achieving the highest ammonium removal efficiency of 96.02% in vitro. In SBR experiments, the bioaugmented reactor (SBR1) demonstrated superior nitrogen and organic matter removal compared to the control (SBR2). By day 40 of the enhancement phase, SBR1 achieved 88.9% ammonium removal and 93.7% COD removal, representing improvements of 20.5% and 17.9% over SBR2, respectively. Microbial community analysis revealed that bioaugmentation enriched Proteobacteria and Bacteroidota phyla, promoting functional guilds like Alcaligenes, Pseudomonas, and Paracoccus, which synergized with indigenous microbiota to enhance metabolic efficiency. This study highlights the potential of HN-AD consortia to overcome limitations of conventional nitrogen removal systems, offering a promising strategy for optimizing wastewater treatment processes.