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A 6‐week feeding trial was conducted to investigate the effects of adding tributyrin (TB), alone and in combination with fructooligosaccharides (FOS) in high soybean meal (SBM) diets on growth performance, innate immunity and intestinal morphology of shrimp (Litopenaeus vannamei). Six isonitrogenous and isolipidic diets were formulated: positive control diet (PC, containing 250 g/kg fishmeal (FM) and 285 g/kg SBM), control diet (C, containing 125 g/kg FM and 439.2 g/kg SBM) and four experimental diets with 10 g/kg TB (T1), 10 g/kg TB + 1.0 g/kg FOS (T2), 10 g/kg TB + 2.0 g/kg FOS (T3) and 10 g/kg TB + 4.0 g/kg FOS (T4) supplemented to the control diet. The results showed that shrimps fed diet C had the poorest growth, and no significant differences in growth performance and survival rates were observed in shrimps fed diets PC, T1, T3 and T4. Dietary TB supplementation significantly enhanced hepatopancreas trypsin, haemolymph ACP and AKP activities and also improved mucosal thickness (MT) (p <.05). Compared with supplementation of TB alone, the combination of TB and FOS not only further improved the above indicators but also enhanced the villus height (VH), hepatopancreas lipase and haemolymph SOD activities, while hepatopancreas MDA level decreased significantly (p <.05), especially in groups with higher doses of FOS (2 and 4 g/kg). In conclusion, partial FM replacement with SBM had negative effects on shrimp, and TB alone and in combination with FOS can improve the growth performance, innate immunity and maintain healthy intestinal morphology of shrimps fed with high SBM diets. [ABSTRACT FROM AUTHOR]

The effects of fructooligosaccharide (FOS) on growth performance, immunity and predominant autochthonous intestinal microbiota of shrimp (Litopenaeus vannamei) fed diets with fish meal (FM) partially replaced by soybean meal (SBM) were evaluated. After acclimation, shrimps (1.82 ± 0.01 g/kg) were allocated into 15 tanks (25 shrimps per tank) and fed five different diets including positive control diet (C0, containing 250 g/kg FM and 285 g/kg SBM), control diet (C, containing 125 g/kg FM, 439 g/kg SBM) and three experimental diets supplemented with 1.0 g/kg FOS (T1), 2.0 g/kg FOS (T2) and 4.0 g/kg FOS (T3) to control diet (C) respectively. Shrimps were fed diets to apparent satiation three times per day, and 15 shrimps from each aquarium were randomly sampled and analysed at the end of the 6‐week feeding trial. The results showed that FBW, WGR, SGR and SR decreased, while FCR and FI increased significantly in control (C) compared with positive control (C0). Besides, significantly decreased trypsase and lipase activities, and SOD, AKP and ACP activities were recorded in control (C) compared with positive control (C0). On the other hand, significantly improved SGR and decreased FCR were observed in groups T1, T2 and T3 compared with control (C). Moreover, lipase and amylase activities enhanced significantly in group T3 compared with the control (C), while GOT and GPT activities dropped significantly with the increment supplementation of FOS in diets. Compared with the control (C), SOD activity enhanced significantly and MDA level decreased significantly in groups T2 and T3, and improved AKP and ACP activities were observed in group T3. In addition, dietary FOS improved the microbial diversity, and suppressed several potential pathogens, such as Vibrio tubiashii, Vibrio parahaemolyticus and Photobacterium damselae‐like strains in the intestine of shrimp. Overall, these results proved FOS could relieve the side effects induced by SBM and supported the use of 2.0–4.0 g/kg FOS in shrimp diets with FM partially replaced by SBM. [ABSTRACT FROM AUTHOR]

The gut microbiota plays key roles in the health and general welfare of fish larvae, the present study characterized the bacterial communities associated with grouper Epinephelus coioides larvae during a period of 22 days post hatch ( DPH) in an intensive hatchery using both cultivation-based and cultivation-independent approaches. Both approaches confirmed that bacteria were present in the gut of larvae before and after the onset of exogenous feeding, and the number of cultiviable bacteria increased gradually from 2 DPH to 22 DPH. A more complex bacterial profile was present in larvae fed fertilizer oyster eggs for 4 days (8 DPH), probably as a result of the onset of exogenous feeding. Interestingly, similar internal microbiota were observed in larvae fed fertilized oyster eggs for 4 days (8 DPH) and rotifers for 2 weeks (22 DPH), although different microbial communities were present in the two feeds. This might suggest that the gut environment of E. coioides larvae selects for a common microbiota, which is more closely related with the rearing water than the two feeds. Therefore, bacterial community of the rearing water may play a critical role in the establishment of gut microbiota of fish larvae and more attention should be paid to its practical modulation by using probiotics. In addition, some potentially beneficial bacteria, such as Lactococcus spp., were the major components of the microbiota associated with fertilized oyster eggs, while these bacteria were not detected in larvae samples. [ABSTRACT FROM AUTHOR]

Recognition of apoptotic cells by macrophages is crucial for resolution of inflammation, immune tolerance, and tissue repair. Cyclooxygenase-2 (COX-2)/prostaglandin E2 (PGE2) and hepatocyte growth factor (HGF) play important roles in the tissue repair process. We investigated the characteristics of macrophage COX-2 and PGE2 expression mediated by apoptotic cells and then determined how macrophages exposed to apoptotic cells in vitro and in vivo orchestrate the interaction between COX-2/PGE2 and HGF signaling pathways. Exposure of RAW264.7 cells and primary peritonealmacrophages to apoptotic cells resulted in induction of COX-2 and PGE2.The COX-2 inhibitor NS-398 suppressed apoptotic cell-induced PGE2 production. Both NS-398 and COX- 2-siRNA, as well as the PGE2 receptor EP2 antagonist, blocked HGF expression in response to apoptotic cells. In addition, the HGF receptor antagonist suppressed increases in COX-2 and PGE2 induction. The in vivo relevance of the interaction between the COX-2/PGE2 and HGF pathways through a positive feedback loop was shown in cultured alveolar macrophages following in vivo exposure of bleomycin-stimulated lungs to apoptotic cells. Our results demonstrate that upregulation of the COX-2/PGE2 and HGF in macrophages following exposure to apoptotic cells represents a mechanism for mediating the anti-inflammatory and antifibrotic consequences of apoptotic cell recognition. [ABSTRACT FROM AUTHOR]

Though primo vessels are frequently found in the lymph near the abdominal aorta of rabbit by Alcian blue dye, the reproductions are still difficult to require considerable skills and technical know-how at dissected tissue of animal species. However, in the inguinal lymph node of a rabbit we found a long-type primo vascular system (LTP) dyed with Alcian blue, from an abdominal lymph vessel to an inguinal lymph node. The length of LTP was over an average length of 9.1 cm. The average diameters of the primo and the lymph vessels were about 23.9 Μm and 242 Μm, respectively. The primo vessels were not floating but adhered to lymph vessels with fascial connective tissue. These primo vessels might be a functional integration in the lymph system. [ABSTRACT FROM AUTHOR]

In this study, we replaced fish meal with peanut meal (PM) in isonitrogenous and isolipidic diets for Pacific white shrimp at inclusion levels of 0, 70, 140, 210, 280 and 350 g kg−1. The diets were hand-fed to three independent groups of shrimp three times a day over a 6-week period. Shrimp fed PM diets at a level of 280 g kg−1 or higher had lower per cent weight gain compared with those fed the basal diet, whereas shrimp fed PM diets at 140 g kg−1 or higher had a lower feed utilization and protein efficiency ratio compared with shrimp fed the basal diet. The feeding rate in shrimp fed PM diets at 350 g kg−1 and the survival and protease activity in shrimp fed PM diets at 210 g kg−1 or higher were lower than that in shrimp fed the basal diet. Diets containing 280 g kg−1 or higher of PM caused an increase in the whole-body moisture content of the shrimp, but decreased whole-body protein and ash contents compared with the basal diet. Nutrient digestibility was lower or tended to be lower in shrimp fed a PM diet compared with those fed the basal diet. The activities of peroxidase and acid and alkaline phosphatases in plasma decreased with increasing levels of PM inclusion up to 210 g kg−1. Superoxide dismutase activity decreased at dietary PM levels of 280 g kg−1 or higher. Aflatoxin B1 residue in the muscle was not affected by any of the treatments and remained low. The data suggest that up to 140 g kg−1 of PM could be included in practical diets for Pacific white shrimp. [ABSTRACT FROM AUTHOR]

The autochthonous microbiota in the foregut, midgut and hindgut of juvenile grouper Epinephelus coioides following the dietary administration of probiotic Bacillus clausii for 60 days were assessed using polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). A complex and generally similar bacterial composition along the digestive tract of E. coioides was detected in the DGGE profiles, while several bacteria showed regional specialization. Similarity dendrogram revealed that the bacterial composition of the foregut was more similar to the midgut than the hindgut. Samples collected from the probiotic group and the control group showed generally similar DGGE patterns, while no significant difference in the total number of bands and Shannon index were observed between the probiotic group and the control group, suggested that probiotic B. clausii exerted no significant effect on the gut microbiota of E. coioides. However, various potentially beneficial bacteria, such as Enterococcus sp.-like and Bacillus pumilus-like bacterium were selectively stimulated by probiotic B. clausii, while some potential harmful species, like Staphylococcus sp.-like and Vibrio ponticus-like bacterium were depressed. These indicated that the gut microbiota was modified to some degree by probiotic B. clausii. Sequences analysis showed that the autochthonous gut bacteria of E. coioides could be classified into four groups, i.e. Proteobacteria, Firmicutes, Actinobacteria and unclassified bacteria. [ABSTRACT FROM AUTHOR]

The apparent digestibility coefficients (ADCs) of dry matter, crude protein, crude lipid, ash, phosphorus, gross energy and amino acids of 10 selected ingredients for juvenile hybrid tilapia (7.05 ± 0.09 g) were determined using 0.5% Cr2O3 as an inert indicator. The feed ingredients tested in this study were corn gluten meal (CGM), corn byproduct, corn germ meal (CG), soybean meal (SBM), fermented soybean meal (FSM), soy protein concentrate (SPC), soy protein isolate, malt sprouts (MS), fish meal (FM) and earthworm meal (EM). The test diets were prepared by incorporation of 30% test ingredients into the reference diet. Reference and test diets were fed to the fish and the faecal samples were collected using a faecal collection column attached to the fish-rearing tanks. The ADCs for dry matter, crude protein, crude lipid, ash, phosphorus and gross energy were 41.7–98.9%, 90.6–99.6%, 73.1–98.8%, 34.1–98.6%, 49.5–99.6% and 45.4–99.7% respectively. Soy protein isolate, FM and EM had higher dry matter, crude protein and gross energy ADCs. Corn byproduct and EM had higher crude lipid ADCs, and CG and EM had higher phosphorus ADCs. Corn germ meal had the highest ash ADC, while CGM had the highest value for gross energy. The lowest dry matter, crude protein, lipid and gross energy ADCs occurred in MS, while the lowest ash and phosphorus ADCs occurred in SPC. The amino acid ADCs ranged from 83.3% to 100%, exhibiting a positive correlation with crude protein digestibility for a given test ingredient. The feed ingredient digestibility of this study may provide useful information about nutrient and energy utilization to facilitate formulation of least-cost practical diets for hybrid tilapia. [ABSTRACT FROM AUTHOR]