Fucoidan derived from Sargassum ilicifolium affects growth and hemato-immunological parameters and antioxidant defense in Oscar (Astronotus ocellatus)

An 8-week feeding trial was conducted to investigate the effects of dietary fucoidan levels (0 mg/kg, 500 mg/kg, 1,000 mg/kg, 1,500 mg/kg, and 2,000 mg/kg) on the hepatic ultrastructure and the transcriptomic landscape within the liver tissue of common carp. The results revealed that the addition of 1,000 mg/kg fucoidan to the diet significantly altered the ultrastructure of hepatocytes. Notably, the quantities of lipid droplets, autolysosomes, enlarged mitochondria, and endoplasmic reticulum were increased in the hepatocytes. The liver transcriptome analysis revealed that DEGs were notably abundant in the 1,000-mg/kg fucoidan group in glucolipid metabolism signaling pathways, including eukaryotes and nicotinate and nicotinamide metabolism, steroid biosynthesis, and PPAR signaling pathways. The quantitative real-time PCR (qPCR) results showed an excellent agreement on those of RNA-seq for both up- and down-regulated genes (a total of 13 genes selected for validation). Furthermore, fucoidan significantly influenced hepatic glucolipid metabolism of common carp at the mRNA level. Notably, the inclusion of lower concentrations of fucoidan in the diet, specifically at 500 mg/kg and 1,000 mg/kg, was found to significantly enhance the expression of mRNA for genes involved in glycolysis, including hk, gk, and pk, as well as genes linked to lipogenesis, such as srebf1, fasn, elovl5, acsl3a, scd, fads2, and cyp24a1. Conversely, higher concentrations of dietary fucoidan, at 1,500 mg/kg and 2,000 mg/kg, were observed to markedly upregulate the mRNA expression of genes associated with gluconeogenesis, including pck1, pck2, gs, gsk3a, gsk3b, and g6pca.1, along with genes related to lipolysis, such as hadhb, acadl, ecil, acacba, cpt1, fabp1, and fabp3. In summary, varying levels of fucoidan intake appear to exert differential influences on the hepatic glucolipid metabolism of common carp, suggesting a complex dose-dependent regulatory mechanism. For the first time, this research has established that fucoidan possesses a pronounced regulatory influence on the hepatic glucolipid metabolism in fish. This discovery not only underscores its potential as an immunostimulant but also opens new avenues for its application as a feed additive, with implications for modulating the nutritional metabolism of aquatic species.

Fucoidan changes lipid accumulation in the liver of common carp (Cyprinus carpio) by modulating lipid and glucose metabolism

Li,

Sun,

Mei

et al. 2024

Comparison of the effects of host-associated (autochthonous) and commercial probiotics on immune responses, growth parameters and intestinal microbiota of Caspian whitefish (Rutilus frisii kutum) fry

Hoseinifar,

Hoseini,

Taheri Mirghaed

et al. 2024

Probiotics are helpful bacteria that safeguard host animals from harmful pathogens. In fish farming, the primary aim of using probiotics is to preserve or reestablish a balance between pathogenic microorganisms and the native bacteria that constitute the intestinal and skin microbial communities of fish. This study investigates the effects of host-associated probiotic (HAP) vs commercial probiotic (CP) on the growth performance, antioxidant defense and immunity of Caspian whitefish fry. Three hundred whitefish fry (1.15 ± 0.03 g) were randomly divided into five treatments in triplicate. Treatments included feeding with the control group (zero), P. acidilactici as a commercial probiotic (CP) at 6 × 108 CFU g -1, and HA Pediococcus pentosaceus at 106, 107 and 108 CFU g-1 for eight weeks. Dietary HAP and CP did not have significant effects on growth indices compared to the control group (P > 0.05). However, HAP at 107 and 108 CFU g-1 and CP significantly increased protein in whitefish carcasses compared to the control group (P < 0.05). Different levels of HAP and CP had a significant effect on whole-body extract (WBE) lysozyme (LZM) activity (P < 0.05). HAP treatment significantly increased WBE ACH50 and bactericidal activity compared to the control and CP group (P < 0.05). Also, in the case of mucosal immune response, different levels of HAP could significantly increase LZM, total immunoglobulin (Ig), agglutination titer, protease and alkaline phosphatase activity compared to the control group (P < 0.05). Whitefish fed HAP showed a significant increase in the activity of WBE antioxidant parameters (SOD, CAT and GPx) compared to the control group (P < 0.05). Also, feeding with HAP could significantly increase autochthonous LAB levels compared control group (P < 0.05); while the total count of intestinal heterotrophic bacteria was not affected (P > 0.05). Overall, the present study showed HA Pediococcus pentosaceus can be considered as beneficial feed additive for whitefish.

The effects of dietary Agaricus bisporus powder on growth performance, haematological indices, and serum immune response in beluga (Huso huso) juvenile

Aminzadeh,

Jafari,

Hoseinifar

2024

IntroductionThe present study investigates the effects of mushroom powder (MP) on growth parameters, haematological indices, innate immune response, and serum biochemical indices in beluga (Huso huso) juveniles.MethodsA total of 120 fish (45 ± 0.5 g) were stocked with 10 fish in each 300-L tank. Experimental diets were prepared by inclusion of 0, 0.5, 1.0, and 2.0% MP. At the end of the feeding trial haemato-immunological parameters as well growth performance were measured.ResultsThe growth parameters results revealed that body weight, specific growth rate (SGR), and body length increased significantly in the fish fed diets containing 1% and 2% MP (P<0.05). Haematological indices results indicated that none of the experimental diets showed significant effects on red blood cell count (RBC), hemoglobin, mean corpuscular volume (MCV), mean cell hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) (P >0.05). However, the haematocrit increased significantly in the fish fed diets containing 1% MP compared to the control (P<0.05). White blood cell count (WBC) in the fish fed 2% MP was significantly higher than that in the fish fed 0% and 0.5% MP (P<0.05). Furthermore, MP treatments caused no significant change in the activity of complement C3 (P >0.05), while C4 activity increased significantly in the fish fed 2% MP (P<0.05). Total immunoglobulin in 1% MP had no significant difference when compared with control (P >0.05). Albumin level was significantly higher in fish fed 2% MP compared to control (P<0.05).DiscussionIn conclusion, MP (2%) can be considered to improve growth parameters and immune indices in beluga juveniles.