Effects of dietary mannan oligosaccharide on the survival,growth, immunity and digestive enzyme activity of freshwater crayfish,Cherax destructor Clark (1936)

The aim of this experiment was to determine the effects of dietary supplementation of Bio‐Mos^® as a source of mannan oligosaccharide (MOS) on the growth, survival, immunity and digestive enzyme activity of freshwater crayfish, Cherax destructor (yabby). A basal diet and another diet with 0.4% of Bio‐Mos^® supplemented to the basal diet were formulated. Each diet was provided to eight yabbies (35.14 ± 0.48 g, initial weight) replicated 3 times in individual 250‐L plastic cylindrical tanks for a duration of 56 days. Each tank was provided with an independent recirculating water system filtered with a biological filtration. Growth parameters such as weight, specific growth rate and average weekly gain of Bio‐Mos^®‐fed yabbies were higher (P < 0.05) than yabbies fed the control diet. Total haemocyte count, granular cells and semi‐granular cells were also higher in the yabbies fed Bio‐Mos^® diet. Protease activity was higher in hepatopancreas, and amylase activity was higher in the guts of yabbies fed Bio‐Mos^® diet. The results implies that supplementation of MOS through Bio‐Mos^® can effectively improve growth and immunological condition of yabbies.     

乳制品中益生菌研究进展

对益生菌的概况、来源、种类和特点,以及其在乳制品中的应用等研究进展进行概述。益生菌具有抑制病原菌、刺激免疫功能、降低胆固醇及心血管疾病风险、抗肿瘤和其他健康效应等特点,结合乳本身的营养价值,为其综合开发和利用奠定一定基础。益生菌具有利于人体生长发育的营养和生理功能,其在功能乳制品开发方面的重要性应加以重视。     

The effects of oligofructose on growth performance,survival and autochthonous intestinal microbiota of beluga (Huso huso) juveniles

Preliminary experiments were undertaken to investigate the effects of oligofructose on beluga sturgeon (Huso huso) growth performance, survival and culturable autochthonous intestinal microbiota. Juveniles (20 g) were fed diets containing varying levels of oligofructose (10, 20 and 30 g kg^?1) at 2–3% body weight per day for 7 weeks. Compared to the control group, no significant (P > 0.05) effect on growth performance was observed in fish fed diets supplemented with oligofructose at 10 and 20 g kg^?1. However, compared to the 20 g kg^?1 group, feeding oligofructose at 30 g kg^?1 resulted in adverse effects on growth performance. Dietary supplementation of oligofructose at 20 g kg^?1 significantly increased survival rate. Microbiological assessment indicated that the viable culturable autochthonous levels were not affected by dietary oligofructose. Although lactic acid bacteria (LAB) were not a dominant component of the endogenous autochthonous microbiota, LAB levels were significantly elevated in fish fed 20 g kg^?1 dietary oligofructose. This elevated LAB population was able to persist for at least 1 week after reverting the prebiotic group back to a control diet. This study encourages further research on different aspects of oligofructose in sturgeon culture with clear emphasis on optimizing dosage levels.     

Effects of Bacillus subtilis strains and the prebiotic Previda® on growth,immune parameters and susceptibility to Aeromonas hydrophila infection in Nile tilapia,Oreochromis niloticus

This study was conducted to evaluate the individual and combined effects of long‐term feeding of diets containing two probiotic Bacillus subtilis group strains (Aqua NZ and AP193) and the prebiotic Previda^®, a commercial hemicellulose extract, on growth performance, immune parameters and Aeromonas hydrophila susceptibility of juvenile Nile tilapia, Oreochromis niloticus. Nile tilapia of average weight 7.47 ± 0.11 g were fed diets formulated with the probiotics and/or the prebiotic, or a control diet for 8 weeks and, subsequently, challenged with A. hydrophila by intragastric gavage at a dosage of 3.9 × 10⁷ CFU per fish. Fish attained a mean weight of 59.5 ± 0.99 g at the end of the growth period. Under the conditions of the present trial, none of the diets significantly improved mean per cent weight gain (P = 0.70), thermal growth coefficient (P = 0.88) or feed conversion ratio (P = 0.87) of Nile tilapia. Except for the diet containing the prebiotic Previda^® only (P = 0.17), all other diets resulted in significantly higher fish survival compared to the control (P < 0.05). The combined effect of the prebiotic and probiotic strains emerged as the most important diet with respect to mortality reduction. The mean lysozyme and respiratory burst activities did not show any significant differences between treatments and control (P = 0.14 and 0.32, respectively). Thus, these probiotic strains used in this study have the potential to prevent disease due to A. hydrophila in O. niloticus.     

In vitro selection of a synbiotic and in vivo evaluation on intestinal microbiota,performance and physiological response of rainbow trout (Oncorhynchus mykiss) fingerlings

The aim of this study was to determine the best synbiotic combination (based on growth and short chain fatty acids production) between Pediococcus acidilactici and five prebiotics in vitro, inulin, fructooligosaccharide (FOS), xylooligosaccharide (XOS), galactooligosaccharide (GOS), isomaltooligosaccharide (IMO). The best in vitro growth under aerobic and anaerobic culture condition was observed in the treatment, P. acidilactici + GOS. Furthermore, the study of short chain fatty acids (SCFA) production at the end of exponential growth phase revealed that the major SCFA produced was propionic acid in all synbiotic treatments except for the P. acidilactici + GOS treatment where butyric acid production was significantly higher compared with the other treatments. Based on the results of in vitro studies, P. acidilactici + GOS that were selected as synbiotic and rainbow trout fingerlings (15.04 ± 0.52 g) were fed on diet supplemented with the selected synbiotic. After 8 weeks of feeding, growth performance, intestinal microbiota and physiological responses were evaluated. Growth performance was significantly improved by synbiotic feeding. No significant differences of haematological parameters were revealed between the different treatments. Level of presumptive autochthonous lactic acid bacteria was elevated, while total autochthonous bacterial level remained unaffected. These results showed that P. acidilactici + GOS can be considered as an efficient synbiotic for rainbow trout.     

Growth performance and immune response of prebiotic honey fed pacific white shrimp Litopenaeus vannamei to Vibrio parahaemolyticus infection

ABSTRACT

The present study was aimed to evaluate the effectiveness of administration of honey as a prebiotic in improving growth performance, immune response, and resistance of Pacific white shrimp Litopenaeus vannameito to Vibrio parahaemolyticus infection. In the present study, the bee honey added to practical diet at levels of 0.0%, 0.25%, 0.5%, 0.75%, and 1.0%. Shrimps were fed one of the tested diets in triplicates for 70 days. After the feeding trial, challenged was conducted with V. parahaemolyticus for two and five days. The growth performance and immune responses of shrimp in treatments with prebiotic honey were better than control one. Pacific white shrimp fed 0.75% honey showed highest survival after bacterial infection (73.33%), while lowest survival was found in the control treatment (43.33%). It may be concluded that the administration of honey at level of 0.75% was effective in improving the growth performance, immune response, and resistance of shrimp to V. parahaemolyticus infection.     

The effects of dietary inulin and Jerusalem artichoke (Helianthus tuberosus) tuber on the growth performance,haematological, blood chemical and immune parameters of Nile tilapia (Oreochromis niloticus) fingerlings

This study investigated the effects of dietary inulin or Jerusalem artichoke (JA) on the growth performance, haematological, blood chemical and immune parameters of Nile tilapia fingerlings. Five treatment diets were designed to incorporate inulin at 0 (basal diet), 2.5 and 5.0 g/kg and JA at 5.0 and 10.0 g/kg. Two basal diets including fish meal and formulated experimental feed were used for fry and fingerling growing periods, respectively. During the fry growing period, larvae were fed treatment diets for 4 weeks. There were no significant differences in growth performance or survival rate. Fingerlings were then nursed with the formulated experimental diets from weeks 5 to 12. Fingerlings fed on inulin at 5.0 g/kg or JA at either level had better growth performance and survival rate than that fed on the basal diets. There were no significant differences in body composition. Dietary prebiotic inulin and JA increased red blood cell number (p < .05). Among the five blood chemistry parameters examined, both inulin at 5.0 g kg and JA (5.0 and 10.0 g/kg) increased blood protein (p < .05). Dietary inulin at 5.0 g/kg and JA at 5.0 and 10.0 g/kg increased total immunoglobulin and lysozyme activity (p < .05). Both inulin and JA inclusion diets increased alternative complement activity (p < .05). Taken together, dietary inulin at 5 g/kg and JA at 5.0 and 10.0 g/kg had beneficial effects on the growth performance, survival rate and immune of Nile tilapia fingerlings.     

Effects of two dietary probiotics (Bacillus subtilis or licheniformis) with two prebiotics (mannan or fructo oligosaccharide) in Japanese eel,Anguilla japonica

A 12‐week feeding trial was conducted to investigate the effects of two dietary probiotics; Bacillus subtilis KCTC 2217 or Bacillus licheniformis KCCM 11775 with two prebiotics; mannan oligosaccharide (MOS) or fructooligosaccharide (FOS) in Japanese eel. Fish averaging 12.8 ± 0.47 g (mean ± SD) were randomly distributed into five treatments with triplicate tanks. A basal control diet (CON) and four synbiotic diets supplementing B. subtilis + MOS (BSM), B. subtilis + FOS (BSF), B. licheniformis + MOS (BLM), and B. licheniformis + FOS (BLF). Weight gain and specific growth rate of fish fed all synbiotic diets were higher than those of fish fed CON. Immune‐related gene expression of heat shock protein 70 and immunoglobulin M of fish fed BSF and BLM were significantly higher than those of fish fed CON. Fish fed BSF and BLM had significantly higher intestinal villi length than those of fish fed BLF and CON (p < .05). Disease resistance against Aeromonas hydrophila of fish fed all synbiotic diets were significantly higher than those of fish fed CON (p < .05). Therefore, these results indicated that dietary B. subtilis with FOS (BSF) and B. licheniformis with MOS (BLM) could have beneficial effects on intestinal morphology, and immune‐related gene expression in Japanese eel.     

Effects of crude protein and lactose levels in diets on growth performance,intestinal morphology,and expression of genes related to intestinal integrity and immune system in weaned piglets

To evaluate the effects of crude protein (CP) and lactose (LAC) for weaned piglets on performance, intestinal morphology, and expression of genes related to intestinal integrity and immune system, 144 piglets with initial weight 7.17 ± 0.97 kg were allotted in a randomized design, in a 2 × 3 factorial arrangement (20.0% and 24.0% CP and 8.0%, 12.0%, and 16.0% LAC) with eight replicates. Piglets fed 20.0% CP had greater weight gain and feed intake. Including 12.0% LAC in the 20.0% CP diet provided higher villous height in the duodenum than 8.0% LAC, and 12.0% or 16.0% LAC in the 24.0% CP diet resulted in higher villous height in the jejunum and ileum, and higher villi/crypt ratio in the ileum than 8.0% LAC. No effects of CP and LAC on interleukin‐1β and tumor necrosis factor‐α mRNA were observed. The 16.0% LAC diet provided higher gene expression of transforming‐β1 growth factor. Feeding 20.0% CP resulted in better performance than 24.0% CP. The 12.0% LAC diet promoted greater genetic expression of occludin and zonula occludens. Including 12.0% LAC in the diet may improve intestinal epithelial morphology and integrity, and these improvements are more evident when piglets are fed diets with 24.0% CP.     

Effects of a prebiotic, Immunogen®, on feed utilization, body composition, immunity and resistance to Aeromonas hydrophila infection in the common carp Cyprinus carpio (Linnaeus) fingerlings

This study evaluated the effects of a commercial prebiotic, Immunogen, on feed utilization, growth rate, immunity promotion and carcass composition of the common carp Cyprinus carpio fingerlings. The fingerlings were adopted for 2 weeks and then reared in triplicate groups in 250-l tanks (n = 15 per tank with average initial weights of 11.12 ± 0.55 g). The fish fed on five isonitrogenous and isoenergetic experimental diets containing different levels of Immunogen (0, 0.5, 1, 1.5 and 2.5 g prebiotic/kg diet) to apparent satiation thrice a day for 8 weeks. Weight gain showed no differences among the groups fed different Immunogen levels. Both feed efficiency ratio and protein efficiency ratio significantly (p < 0.05) increased with increasing Immunogen levels from 0.5 to 1.5 g/kg diet. The highest protein content (p < 0.05) was found in the fish fed a diet containing 2.5 g/kg prebiotic. Haematological parameters and plasma total protein concentration were also significantly higher (p < 0.05) in the fingerlings fed diets containing 1.5 and 2.5 g/kg prebiotic in relation to the control. The control fish contained the highest mean of total bacterial counts. The lowest mean (p < 0.05) of total bacterial counts was observed in the fish fed the diet containing 2.5 g/kg Immunogen. The present study reveals that a dietary Immunogen supplementation from 1 to 1.5 g/kg is capable to improve the feed efficiency and growth performance of C. carpio fingerlings as well as their resistance to A. hydrophila infection.