The potential of a combination of pungent spices as a novel supplement in gilthead seabream (Sparus aurata) diets to aid in the strategic use of fish oil in aquafeeds: a holistic perspective.

This work studied the potential of a combination of pungent spices (capsicum, black pepper, ginger, and cinnamaldehyde) to be used as a supplement in diets of gilthead seabream (Sparus aurata; 44.1 ± 4.2 g). During 90 days, fish were fed three experimental diets with low inclusion of fish oil and containing poultry fat as the main source of lipids, supplemented with graded levels of the tested supplement: 0 (control), 0.1 (SPICY0.1%), and 0.15% (SPICY0.15%). As a result, the pungent spices enhanced the growth performance, the activity of the bile-salt-activated lipase in the intestine, and decreased fat deposit levels within enterocytes. The SPICY0.1% diet reduced the feed conversion ratio and the perivisceral fat index and lipid deposits in the liver. Moreover, the ratio of docosahexaenoic acid/eicosapentaenoic acid in fillet increased in fish fed the SPICY0.1% diet, while the hepatic levels of docosahexaenoic acid and total n-3 polyunsaturated fatty acids increased in fish fed the SPICY0.15% diet. Furthermore, there was an effect on the expression of some biomarkers related to lipid metabolism in 2-h postprandial fish (fasn, elovl6, scd1b, cyp7a1, lpl, and pparß), and in 48 h fasted-fish fed with the SPICY0.1% diet, a regulation of the intestinal immune response was indicated. However, no significant differences were found in lipid apparent digestibility and proximate macronutrient composition. The spices did not affect biomarkers of hepatic or oxidative stress. No differences in microbial diversity were found, except for an increase in Simpson's Index in the posterior intestine of fish fed the SPICY0.1% diet, reflected in the increased relative abundance of the phylum Chloroflexi and lower relative abundances of the genera Campylobacter, Corynebacterium, and Peptoniphilus. In conclusion, the supplementation of gilthead seabream diets with pungent spices at an inclusion of 0.1% was beneficial to enhance growth performance and feed utilization; reduce fat accumulation in the visceral cavity, liver, and intestine; and improve the fish health status and condition. Results suggest that the tested supplement can be used as part of a nutritional strategy to promote a more judicious use of fish oil in fish diets due to its decreasing availability and rising costs.

Olive oil cake extract stabilizes the physiological condition of lipopolysaccharide-challenged piglets by reducing oxidative stress and inflammatory responses and modulating the ileal microbiome.

Olives are a rich source of compounds with antioxidant and anti-inflammatory activities. This study was designed to investigate whether a standardized olive cake extract was able to alleviate oxidative stress, inflammation and intestinal villus damage in a model of lipopolysaccharide (LPS)-challenged piglets. Thirty weaned piglets (6.9 ± 0.9 kg) were assigned to five groups using a randomized complete block design. Piglets were fed a basal diet before intraperitoneal (i.p.) injection of physiological saline (C); fed a basal diet alone (CL) or fed a basal diet plus an olive cake extract (OL), antibiotics (AL), or olive cake extract plus antibiotics (OAL) before i.p. injection of LPS. The feeding period lasted for 2 weeks. Piglets were euthanized 4 h after the LPS injection. Systemic oxidative and inflammatory status and intestinal morphology were evaluated. LPS challenge significantly lowered the serum levels of GSH-Px, SOD and ALB and increased the serum concentration of MDA, NO, LDH, ALT, AST, TNF-α, IL-6, DAO and D-xylose (P < 0.05), as extracted from the comparison of piglets in the C and CL groups. Intestinal morphology was altered in the duodenum and ileum, displaying that the CL group had significantly lower villus height (VH), higher crypt depth (CD) and lower VH/CD compared with the control group (P < 0.05). Moreover, feed supplementation was able to partially mitigate the negative effects of LPS challenge in all groups (OL, AL, and OAL), as evidenced by the significantly increased serum levels of GSH-Px, SOD, ALB and IL-10 and decreased concentration of MDA, NO, LDH, ALT, AST, TNF-α, IL-6, DAO and D-xylose, compared with the CL group (P < 0.05). Alterations in intestinal morphology were also prevented and the OL, AL, and OAL groups had significantly lower CD and higher VH/CD compared with the CL group (P < 0.05), both in the ileum and duodenum. Furthermore, the positive effect in the relative abundance of intestinal Lactobacillus and Clostridium at the genus level was also observed for the OL group compared to the CL group. In summary, dietary supplementation with an olive cake extract stabilized the physiological condition of piglets subjected to an acute LPS challenge by reducing oxidative stress and the inflammatory status, improving intestinal morphology and increasing the abundance of beneficial intestinal bacteria. This trial was registered at Zhejiang University (http://www.lac.zju.edu.cn) as No. ZJU20170529.