14-day Challenge Research Articles

Results of a 14-Day Challenge to Improve Dispositional Gratitude in an Academic Nursing Setting.

The benefits of engaging in regular, intentional gratitude practice have been well studied. Interventions incorporating simple gratitude practices, such as the 3 Good Things exercise, may be ideal for increasing dispositional gratitude levels within an academic setting. To assess the impact of a 14-day gratitude-focused wellness intervention on increasing gratitude levels among nursing students, faculty, and staff. Students, faculty, and staff from one College of Nursing were invited to participate in a 14-day gratitude challenge. The Gratitude Resentment and Appreciation Scale - Short Form assessed gratitude levels pre- and post-challenge. Dispositional gratitude scores increased significantly among participants overall (P =.006). Furthermore, dispositional gratitude levels increased significantly regardless of whether participants were already using a tool to practice gratitude at the start of the challenge. Results demonstrate that a 14-day gratitude-focused intervention can improve dispositional gratitude levels among members of the academic nursing community.

Influence of caffeic acid and Bacillus coagulans supplementation on growth, digestive enzymes, immune response, and antioxidant gene expression in common carp (Cyprinus carpio) and its resistance to Aeromonas hydrophila infection

Present study aimed to investigate the efficacy of dietary supplementation with caffeic acid and Bacillus coagulans on growth performance, digestive enzymes, and immunity of common carp (Cyprinus carpio), and also fish resistance against Aeromonas hydrophila. Fish (21.0 ± 0.5 g) divided into four groups: control group (CD, commercial basal diet), caffeic acid (CA, 5 g/kg feed), B. coagulans (BC, 2×107 CFU/g feed), and CA+BC (5 g/kg + 2×107 CFU/g feed) for 8 weeks, followed by a 14-day challenge with A. hydrophila. A significant enhancement was obtained in growth performance of all treated groups compared to CD (P < 0.05). Also, feed conversion ratio was significantly reduced in treated fish compared to CD group (P < 0.05). Fish of BC and CA+BC groups revealed an increase in activity of amylase, lipase, protease, trypsin, and chymotrypsin in the intestinal tissue. In addition, amylase, lipase, protease, and trypsin in CA group exhibited a higher activity than CD (P < 0.05). A lower decrease in aspartate aminotransferase and a higher increase in alkaline phosphatas were observed in BC and CA+BC groups than CD group (P < 0.05). Values of total protein, total immunoglobulin, lysozyme activity, and alternative complement pathway (ACH50) were higher in sera of BC and CA+BC groups than CD (P < 0.05). Additionally, expression of genes related to lysozyme, IL-1β, IL-8, TNF-α, superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPx) in liver tissues of treatment groups were upregulated better than CD (P < 0.05). Furthermore, a significant reduction in mortality was observed in treatment groups compared to CD under the A. hydrophila challenge. These results exhibited that including a combination of caffeic acid and B. coagulans as functional dietary supplements in diet favors common carp health status and growth and, thus, can be recommended in the fish diet.

The Ultimate 14-Day Challenge: The Journey to Becoming an Indonesian U23 National Football Team Player

Abstract This study explores the 14-day selection process for the U23 national football team. A descriptive qualitative approach was used, with data collected through observations and interviews with coaches and athletes involved in the selection program. The findings reveal that the selection process evaluates a wide range of attributes, including physical abilities, technical skills, tactical understanding, mental resilience, and strategic decision-making, all of which influence the final decision. This process not only focuses on physical performance but also highlights the critical role of psychological and tactical aspects in player evaluation. The comprehensive selection approach contributes to forming a more prepared and competitive team for international competitions. The study suggests that a holistic approach to athlete evaluation, covering physical, psychological, and strategic components, leads to better outcomes in terms of team readiness and competitiveness. It is concluded that such a thorough assessment of athletes results in a more prepared and competitive team for international competitions. Keywords: selection, player, football

Efficacy of Lactobacillus acidophilus and yeast cell wall-derived supplements on immunity responses, growth performance, and disease resistance in Cyprinus carpio juveniles.

This study investigated the effects of probiotic Lactobacillus acidophilus (PTCC 1643) (LA) and a commercial yeast cell wall prebiotic (Immunogen®) (IM) on immunoantioxidant, growth, and digestive status, and resistance to Aeromonas hydrophila in Cyprinus carpio juveniles. The fish were fed in five treatments including control (T1), LA1.5 (T2): 1.5 (× 10^8 CFU/g of LA)/kg diet, LA3 (T3): 3 (× 10^8 CFU/g of LA)/kg diet, IM1 (T4): 1g of IM/kg diet, and IM2 (T5): 2g of IM/ kg diet. After 60 days, the function of growth and intestinal protease and amylase showed a significant increase in IM treatments. Serum levels of total protein and superoxide dismutase in LA3 treatment, as well as albumin, catalase, and glutathione peroxidase in LA3 and IM2 treatments were significantly increased. Serum level of malondialdehyde in LA and IM treatments, as well as alkaline phosphatase (ALP) in LA treatments, alanine aminotransferase in LA and IM2 treatments, and lactate dehydrogenase in LA3 treatment was significantly decreased. Serum levels of all the immune parameters in LA3 treatment, as well as alternative complement pathway hemolytic and nitroblue tetrazolium in IM2 treatment were significantly improved. Mucosal level of protease in LA3 and IM2 treatments, total immunoglobulin, and lysozyme in LA and IM2 treatments, as well as ALP and peroxidase in LA3 treatment was significantly increased. Cumulative mortality rate in LA and IM treatments was significantly decreased compared to control after the 14-day challenge with A. hydrophila. It is recommended to include IM2 in the diet of C. carpio juveniles with regard to its beneficial effects on growth and immunity status.

The role of bile acid in regulating head-kidney, spleen and skin immune function of on-growing grass carp (Ctenopharyngodon idella)

Bile acids (BA) are receiving a great deal of attention and interest as critical regulators of the immune system of immune organs. Nevertheless, there are few researches on the effect of BA on immunity of aquatic animals. Hence, the objective of this research was to evaluated the effects of BA supplementation on immune function and the mechanisms in immune organs [head-kidney (HK), spleen (SP) and skin (SK)] of grass carp (Ctenopharyngodon idella). A total of 540 fish (the average body weight was 179.85 ± 1.34 g) were randomly assigned to a normal diet group (NPNL: 29 % protein and 5 % lipid) and five low protein and high lipid diet groups (LPHL: 26 % protein and 6 % lipid) with graded levels of 0 (no supplement), 80, 160, 240 and 320 mg/kg BA for 50 days. Grass carp were subjected to a 14-day challenge with Aeromonas hydrophila after growth experiment. Results indicated that: (1) LPHL group (without BA supplementation) increased SK lesion morbidity compared to NPNL group, and LPHL+160 mg/kg BA supplementation improved the disease resistance; (2) LPHL group (without BA supplementation) decreased the levels of antimicrobial compounds and the gene expressions of antimicrobial peptides in immune organs compared to NPNL group, and LPHL+(160–240) mg/kg BA supplementation significantly increased (P < 0.05) lysozyme (LZ) and acid phosphatase (ACP) activities, complement (C3, C4) and immunoglobulin M (IgM) contents, as well as the gene expressions of hepcidin, antimicrobial peptide 2 A (Leap-2 A), Leap-2B, Mucin2, βdefensin-1 in immune organs of fish; (3) LPHL group (without BA supplementation) aggravated inflammatory response by upregulated pro-inflammatory factors and downregulated anti-inflammatory factors gene expressions compared to NPNL group, and LPHL+240 mg/kg BA supplementation significantly increased transforming growth factor (TGF)-β1, interleukin 11 (IL-11), −4/13 A, TOR, eIF4E-binding proteins (4E-BP)1, S6K1, but markedly reduced (P < 0.05) the gene expressions of tumor, necrosis factor α (TNF-α), interferon γ2 (IFN-γ2), IL-1β, IL-6, IL-8, IL-15, IL-17D, IL-12p35, nuclear factor kappa B p65 (NF-κB p65), c-Rel, inhibitor of κBα (IκBα), IκB kinase β (IKKβ), IKKγ in immune organs of fish. In conclusion, LPHL diet (without BA supplementation) increased SK lesion morbidity and impaired the immunity of immune organs. In addition, LPHL+(160–240) mg/kg BA supplementation enhanced the disease resistance and immunity of grass carp by inhibiting NF-κB signaling molecule and activating TOR signaling molecule.

New insights into the role of myo-inositol in regulating the skin immune response of grass carp (Ctenopharyngodon idella)

Myo-inositol (MI) is a crucial constituent of the cell membrane and has a pivotal role to play in transmembrane signal transduction, ion channel regulation, and cell transport. Fish skin is a vital mucosal immune organ, and there are few studies that have examined the effect of MI on fish skin.Therefore, the purpose of this study was to investigate the role of dietary MI in regulating the skin immune response of grass carp (Ctenopharyngodon idella). A total of 540 fish (221.33 ± 0.84 g) were fed six diets containing graded levels of MI (27.0, 137.9, 286.8, 438.6, 587.7, and 737.3 mg/kg) for 10 weeks. When the growth test was complete, a 14-day challenge was conducted with Aeromonas hydrophila in each group. Our results indicated that the most effective MI concentrations (approximately 438.6–737.3 mg/kg diet) resulted in the following outcomes: (1) MI reduced the morbidity of grass carp skin and increased the thickness of the dense dermis layer. (2) MI enhanced the physical barrier function of the skin, maybe via increasing antioxidant capacity, inhibiting apoptosis, and improving tight junction-related signaling pathways (nuclear factor erythroid 2-related factor 2, p38 mitogen-activated protein kinase, and myosin light chain kinase). (3) MI enhanced skin immune barrier function, possibly via regulating anti-inflammatory and pro-inflammatory cytokines, as well as the target of rapamycin (TOR) and nuclear factor kappa B (NFκB) pathways. This study led to the following conclusion based on its findings: the MI supplementation strengthened the fish skin barrier function and protected it against Aeromonas hydrophila. The dietary MI requirement in on-growing grass carp was estimated to be 370.90 mg/kg by a broken-line method analysis of skin morbidity.

Fermentation and fortification of Sargassum linearifolium with multi-strain probiotics improves mucosal barrier status, inflammatory response and resistance to Vibrio harveyi infection in barramundi Lates calcarifer

While aquaculture intensification increases productivity and profitability, it can lead to increased susceptibility of fish to disease outbreaks. As such, the production of aquafeeds with immunomodulatory properties is currently of significant interest to the aquaculture sector with a view of improving on-farm welfare. This study aimed to assess the effectiveness of the brown seaweed Sargassum linearifolium fortified with the probiotics Lactobacillus casei and Saccharomyces cerevisiae through submerged fermentation in improving growth, overall health and the ability to resist Vibrio harveyi infection in barramundi, Lates calcarifer. Two seaweed-based diets, probiotic-fortified S. linearifolium (referred to as PF-SL) and S. linearifolium without probiotic fortification (referred to as SL), were compared with a standard barramundi diet (control). Barramundi juveniles weighing 4.25 ± 0.09 g were fed the test diets three times daily to satiety for 56 days. The results demonstrated a significantly higher growth performance in fish fed the PF-SL diet when compared to the control. However, there were no notable differences in the apparent digestibility coefficient (ADC) of dry matter, protein, and lipid between PF-SL and control. Fish fed the PF-SL diet showed improved mucosal barrier function in both the skin and intestine, as indicated by the increased density of mucous cells. Similarly, fish fed the PF-SL diet exhibited higher glutathione peroxidase and total antioxidant activity than the control. The qRT-PCR revealed significant upregulation in the expression of anti-inflammatory genes (occludin, claudin1 and nrf2) and downregulation in the expression of proinflammatory genes (hsp70 and tnf-α) in fish fed the PF-SL diet. Furthermore, the PF-SL diet resulted in a 27% mortality in a 14-day challenge trial with V. harveyi, which was lower than the mortality rates of the SL (46%) and control (67%). Overall, this study demonstrates that feeding juvenile barramundi with probiotic-fortified brown seaweed S. linearifolium was able to improve growth, immunity, and resistance against Vibrio harveyi infection, suggesting significant potential for application across the aquaculture industry for improved fish welfare.

An emerging role of guanidine acetic acid in rescuing immune function injured by Aeromonas hydrophila in grass carp (Ctenopharyngodon idella)

Guanidine acetic acid (GAA) is a safe feed additive and the only precursor for the creatine synthesis of vertebrates. Aeromonas hydrophila is a major fish pathogen causing severe morbidity and mortality in the aquaculture sector. Under the current intensive farming system, A feed additive that can improve fish disease resistance is urgently needed. In teleost fish, the spleen (SP) and head kidney (HK) play a crucial role in peripheral immunity organs and fish skin (SK) serves as one of the most important mucosal barriers. Thus, the study focused on immune defense substances, inflammatory process, and mechanisms of molecular action in the HK, SP, and SK of on-growing grass carp (169.46–600.89 g). The fish were fed graded levels of GAA (0, 150, 300, 450 and 600 mg/kg) for 60 days, and then conducted a 14-day challenge experiment by intraperitoneal injection of Aeromonas hydrophila. In our results, we found that 300 or 450 mg/kg GAA could down-regulate the pro-inflammatory cytokines IL-(1β, 6, 12p40 and 17D), TNF-α and IFN-γ2 mRNA expression, and up-regulate the pro-inflammatory cytokines IL-(10, 11 and 4/13 A) and TGF-β1 mRNA expression in the HK, SP and SK. Furthermore, 300 or 450 mg/kg GAA could up-regulate the mRNA expression and promote the protein phosphorylation of STAT3 in the HK, SP and SK. Indicating that in the case of Aeromonas hydrophila. challenge, GAA could enhance the immune defense and mediated the inflammatory process, possibly via the JAKs-STATs signaling pathway in fish.

ROLE OF SMARTPHONES IN INCREASING PHYSICAL ACTIVITY IN SECONDARY SCHOOL STUDENTS

In today's world, physical activity is gaining more importance, not only in academic community, but also with the general public. Nowadays, many students expect to see involvement of new technologies in school such as smartphones, tablets, and computers. The level of physical activity is very easily affected by various external influences such as smartphone apps, which may be ideal in increasing physical activity. Smartphone apps are considered motivational tools in increasing physical activity. The aim of the study was to analyse the role of smartphones in increasing physical activity in secondary school students. The study group was chosen purposively to meet the aim of the study. The following criteria applied: a) participants should not have health issues; b) participants should be from the same year of students. The group consisted of 113 secondary school students [(Male control group n = 30 (26.54 %); Male experimental group n = 25 (22.12 %); Female control group n = 30 (26.54 %); Female experimental group n = 28 (24.80 %)]. The current level of physical activity was detected by using the smartphone app - Samsung Health [(Samsung Electronics Co., Ltd.; Suwon, the Republic of Korea; Android 5.17.1.003; iOS 1.5)]. Two 14-day challenges were created to increase physical activity in the participants. To determine the statistical significance of 2 control groups (n = 60, 53.08 %) and 2 experimental groups (n = 53; 46.92 %) we applied the Wilcoxon Signed-rank Test (Wtest p &lt; 0.01, p &lt; 0.05). To verify 4 independent study groups, we applied the Mann-Whitney U-test (Mwtest p &lt; 0.01, p &lt; 0.05). The material and practical significance was evaluated by using the effect size coefficient (r) (r = 0.10 - small, r = 0.30 - medium, r = 0.50 - large effect size). The first 14-day challenge resulted in improvements in both control and experimental groups of secondary school students (p &lt; 0.01). After 28-day challenge, we recorded the improvements in the female experimental group (p &lt; 0.01), male control and experimental groups (p &lt; 0.01) and female control group (p &lt; 0.05). When comparing the independent study groups, we recorded improvements, which were significant at 1.00 % and 5.00% level. Secondary school students are increasingly using smartphone apps routinely in more areas of their personal lives. Smartphone apps aimed at increasing physical activity are effective in helping secondary school students to achieve the required physical activity level. Our study provides evidence that the technique of challenges used in the smartphone app - Samsung Health significantly (p &lt; 0.01, p &lt; 0.05) increase the physical activity level of the secondary school students. According to our results, we recommend using the smartphone app - Samsung Health as a motivational tool in increasing the physical activity in secondary school students.

Dietary supplementation of fish protein hydrolysate in high plant protein diets modulates growth, liver and kidney health, and immunity of barramundi ( Lates calcarifer )

A 60-day feeding trial was carried out to investigate the effects of fish protein hydrolysate (FPH) in high lupin meal (LM) diets on growth, health and immunity of barramundi. Fish were fed a fishmeal-based control diet (FM) and three test diets to replace 75% fishmeal protein in the control diet by lupin meal alone (LM), lupin meal with FPH (LM+FPH) and fermented lupin meal with FPH supplementation (FLM+FPH). Each dietary group was stocked with 120 fish with an initial weight of 6.18 ± 0.08 g and fed three times daily to apparent satiation. Fish fed the LM diet had significantly lowered final body weight and specific growth rate compared with control and the remaining dietary groups (p < .05). The decreased growth performance was further exacerbated by liver steatosis and necrosis in the kidney of LM-fed fish. Fish fed the FLM+FPH diet had significantly increased white blood cells and protein contents compared with the control. A significant reduction in mortality was observed in fish fed FLM+FPH compared with fish fed the LM diet following a 14-day challenge with Vibrio harvei. Overall, this study suggests that high LM diets with FPH supplementation could be incorporated into the diet of juvenile barramundi without compromising growth and health.

PEG-modified subunit vaccine encoding dominant epitope to enhance immune response against spring viraemia of carp virus.

Spring viraemia of carp (SVC) caused by spring viraemia of carp virus (SVCV) can infect almost all fish of cyprinids, which bring huge economic losses to aquaculture. Glycoprotein (G), as the most important antigenic determinant protein of SVCV, is widely considered as an effective method against SVCV. In our previous study, we found that G3 (131 aa) is the potential dominant antigen epitope that induces strong immune responses similar to G protein (510 aa). Here, in order to further improve the immune effect, we reported a subunit vaccine (PEG-G3) constructed by PEG-modified dominant epitope protein (G3). The results of serum antibody production, enzyme activities and immune-related genes expression showed that PEG-G3 induces significantly stronger immune protective responses against SVCV than G3. PEG modification significantly increased the serum antibody level of the vaccine, which increased significantly after immunization and reached the peak at 21day post-vaccination. T-AOC and AKP activities in the lowest concentration group (5μg) of PEG-G3 were significantly higher than those in the highest concentration group (20μg) of G3. In PEG-G3 group, the expression of almost all genes increased at least 4 times compared with the control group. After 14-day challenge, the RPS (relative percentage survival) of the highest concentration of PEG-G3 group was 53.6%, while that of G3 group is 38.9%. Therefore, this work shows that PEG modification and dominant epitope screening may be effective methods to improve the immune protective effect of vaccines and to resist the infection of aquatic animal viral diseases.

Supplementation of Hermetia illucens Larvae in Poultry By-Product Meal-Based Barramundi, Lates calcarifer Diets Improves Adipocyte Cell Size, Skin Barrier Functions, and Immune Responses.

A 6-week feeding trial was performed to examine the effects of supplementing Hermetia illucens (HI) larvae meal when fishmeal (FM) was replaced with poultry by-product meal (PBM) in juvenile barramundi, Lates calcarifer diet. The effect was evaluated in terms of barramundi growth, filet quality, internal tissue structure, serum biochemistry, skin neutral mucins, immune response, and resistance to Vibrio harveyi. Three isonitrogenous (48% crude protein) and isolipidic (18% crude lipid) diets: an FM-based diet (control) and two diets containing 60 and 75% of PBM supplemented with 10% HI larvae (60PBM + HI and 75PBM + HI) were formulated. A total of 225 barramundi, with an average weight of 15.87 ± 0.14 g, were randomly distributed into nine tanks, each holding 25 fish. There were no significant effects of test diets on growth, but feeding HI-supplemented PBM diets significantly increased the survival rate. A significantly reduced intraperitoneal fat index in HI-supplemented-PBM-fed fish was correlated to a decreased size of peritoneal adipocytes. The observation of no histopathological alteration of the liver in the HI-supplemented-PBM-fed fish was further supported by significant alterations in serum biochemistry, in particular, a decreasing tendency of alanine transaminase, glutamate dehydrogenase, and total bilirubin. A 14-day challenge with V. harveyi indicated that HI-supplemented PBM diets reduced the infection rate in barramundi. After 24 h of infection, increased serum (lysozyme) and skin barrier functions, down-regulation of interleukin-1beta, and upregulation of interleukin-10 were found in HI-supplemented-PBM-fed fish.

Effects of dietary tamarind pulp extract on growth performance, nutrient digestibility, intestinal morphology, and resistance to Aeromonas hydrophila infection in Nile tilapia (Oreochromis niloticus L.)

ABSTRACT The effect of tamarind pulp extract (TPE) on the growth performance, apparent nutrient digestibility, intestinal morphometrics, body proximate composition, and resistance against Aeromonas hydrophila infection in Nile tilapia was determined. The fish were fed experimental diets formulated to contain 0.0 (control), 5, 10, 15, or 20 g TPE/kg diet at 3% body weight daily for 84 days. Thereafter, a 14-day challenge test with A. hydrophila infection was done. The results showed that TPE supplementation significantly (P < 0.05) enhanced the fish growth, protein efficiency ratio, apparent lipid and protein digestibility, villi height, and absorption area at levels of 10–20 g/kg diet compared to the control diet. Similarly, TPE supplementation increased the crude lipids and ash contents in the fish body. Postchallenge fish fed TPE-supplemented diets showed a higher survival rate relative to fish fed the control diet. The results demonstrated that dietary TPE promoted growth, nutrient digestibility, and protection against A. hydrophila infection in Nile tilapia, and its inclusion at 15 g/kg diet is therefore recommended.

Growth performance, non-specific immunity, intestinal histology and disease resistance of Litopenaeus vannamei fed on a diet supplemented with live cells of Clostridium butyricum

This study conducted a 42-day feeding trial and a subsequent 14-day challenge test to Vibrio parahaemolyticus to determine the effects of Clostridium butyricum CBG01 on the growth, immune responses, intestinal histology and disease resistance of Litopenaeus vannamei (initial weight 1.60 ± 0.02 g). Shrimp were fed with seven experimental diets containing different doses of C. butyricum with 0, 1 × 107, 1 × 108, 1 × 109, 1 × 1010, 1 × 1011 and 1 × 1012 cfu/kg (the control, LA, LB, LC, LD, LE and LF, respectively). The result indicated that specific growth rate and weight gain of shrimp in LE and LF group were significantly improved while feed conversion ratio for all treatments were significantly reduced as compared to the control (P < .05). The intestinal villus height of shrimp in all treatments was significantly higher than the control (P < .05), and the intestinal wall thickness in treatments except LE were higher than the control (P < .05). The activities of alkaline phosphatase (AKP), acid phosphatase (ACP), lysozyme (LZM) and total nitric oxide synthase (TNOS) in the serum of shrimp for LE and LF group were all significantly enhanced (P < .05). However, no significant difference in the superoxide dismutase (SOD) activity was found among the control, LA, LB, LC, LD and LF. The respiratory burst activity of hemolymph for the shrimp in LB, LC, LE and LF significantly higher than the control (P < .05). The expression level of Toll, Imd and Relish gene in lymphoid organ of shrimp in LC, LD, LE and LF were higher significantly those in the control (P < .05). After injection of inactivated V. parahaemolyticus, Relish gene expression level in LE and LF was significantly up-regulated at 1 and 2 h (P < .05). In the challenge test to V. parahaemolyticus, the cumulative mortality of shrimp in LD, LE and LF were significantly lower than the control (P < .05). These results suggested that 1011 and 1012 cfu/kg C. butyricum supplemented into feed could significantly improve the growth performance, immunity capacity and resistance against V. parahaemolyticus of L. vannamei, also have a positive effect on the intestinal morphological structure.

Regulation of growth, intestinal microbiota, non-specific immune response and disease resistance of sea cucumber Apostichopus japonicus (Selenka) in biofloc systems

Bioflocs are not only a source of supplemental nutrition but also provide substantial probiotic bacteria and bioactive compounds, which play an important role in improving physiological health of aquatic organisms. A 60-day experiment was conducted to investigate the growth, intestinal microbiota, non-specific immune response and disease resistance of sea cucumber in biofloc systems with different carbon sources (glucose, sucrose and starch). Control (no biofloc) and three biofloc systems were set up, and each group has three replicates. The results showed that biofloc volume (BFV) and total suspended solids (TSS) increased in the sequences of glucose > sucrose > starch and green sea cucumber > white sea cucumber during the experiment. The highest specific growth rates (SGRs) were observed in biofloc system with glucose as carbon source, which also had relatively lower glucose, lactate and cortisol levels in coelomic fluid and higher glycogen content in muscle compared to other groups. There were significant increased Bacillus and Lactobacillus counts of sea cucumber intestine in biofloc systems, and the activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx) also showed obvious ascending trends. Significant increases in total coelomocytes counts (TCC), phagocytosis, respiratory burst, complement C3 content and lysozyme (LSZ) and acid phosphatase (ACP) activities of sea cucumber were all found in biofloc system (glucose). The expression patterns of most immune-related genes (i.e. Hsp90, Hsp70, c-type lectin (CL), toll-like receptor (TLR)) were up-regulated, suggesting the promotion of pathogen recognition ability and immune signaling pathways activation by biofloc. Furthermore, green and white sea cucumber had significantly higher survival rates in biofloc systems during the 14-day challenge test. In conclusion, biofloc technology could improve growth and physiological health of A. japonicus, by optimizing intestinal microbiota, strengthening antioxidant ability, enhancing non-specific immune response and disease resistance against pathogens, meanwhile glucose was recommended as optimal carbon source in biofloc system of sea cucumber culturing.

Pen trial of estrogen-induced conditioned food aversion to eggs in raccoons (Procyon lotor)

Aversive conditioning is a promising but unproven non-lethal approach to reducing mammalian depredation on the eggs of ground-nesting birds, terrapins and sea turtles. This research tested the efficacy of oral estrogen concealed in a bland carrier as an aversive agent for wild-caught raccoons (Procyon lotor) under controlled conditions. Nine treatment group raccoons were given six estrogen-injected eggs every other day during a 14-day treatment phase, and then given a combination of two estrogen-injected eggs, two fresh eggs, and two carrier-only injected eggs every other day during a 14-day challenge phase. Nine control group animals received six carrier-only injected eggs every other day during the treatment phase, and then two fresh eggs and four carrier-only injected eggs every other day during the challenge phase. All treatment animals exhibited a conditioned food aversion (CFA) after 1–8 egg feedings (15–116 mg of estrogen per kilogram of body mass). All later sampled at least a few eggs, but they consumed fewer eggs than the control animals during both the treatment phase (p < 0.001) and challenge phase (p < 0.001). No raccoon could distinguish treated from untreated eggs during the challenge phase (p = 0.740); the treatment was undetectable by visual or olfactory cues. We observed no conspicuous changes in the feeding activity, behavior or demeanor of the treatment animals. Treatment and control animals ate (p = 0.629) and drank (p > 0.05) comparably. Treatment animals gained less mass than control animals (p = 0.013), but there was no apparent relationship between estrogen intake and mass change (p = 0.912). Testes of treatment males were similar in volume and mass (p = 0.712) to those of control males. Treatment animals experienced higher frequencies of abnormal feces (p < 0.005) and dermatitis (p = 0.001) than control animals. A treatment female died during the trial from an aborted late-term pregnancy, probably induced by the estrogen. Necropsies revealed no obvious tissue or organ damage from estrogen exposure. The conditions of this pen trial provide a conservative test of the potential for using an estrogen-induced CFA as a management tool for reducing egg consumption in the wild. Ingestion of 20–80 mg kg−1 of estrogen delivered over 1–4 days would be sufficient to bring about a reduction in egg predation using this method. A full-scale field trial of estrogen is likely to be productive under circumstances where all of the target population is subject to treatment.

Effects of dietary Yucca meal on growth, haematology, non-specific immune responses and disease resistance of juvenile Nile tilapia, Oreochromis niloticus (Linnaeus, 1758)

A 10-week feeding trial was conducted to determine the effects of dietary yucca meal supplementation on growth, haematology, non-specific immune responses and disease resistance in juvenile Nile tilapia, Oreochromis niloticus. Six isonitrogenous and isoenergetic experimental diets were formulated to contain 0% (YMS0), 0.1% (YMS0.1), 0.3% (YMS0.3), 0.5% (YMS0.5), 1% (YMS1.0) and 2% (YMS2.0) dietary yucca meal on the dry weight basis. Results of this study showed a higher growth performance for YMS0.1 group with significant differences with YMS0.5, YMS1.0 and YMS2.0 groups. In addition, whole-body protein content of fish fed the YMS0.1 diet was significantly higher as compared to YMS0. Plasma lysozyme activity significantly increased in YMS0.1 group comparing to YMS0 and YMS0.5 groups. Respiratory burst activity of phagocytic blood cells was significantly enhanced when fish were fed the YMS0.1 diet. Results also showed that yucca meal supplementation had moderate effects on glutamic oxaloacetic transaminase and cholesterol levels. After the 14-day challenge test with Aeromonas hydrophila, cumulative survival of fish fed YMS0.1 diet was significantly higher than that of fish fed diet YMS0, YMS1.0 and YMS2.0. These results suggest that the optimum dietary yucca meal inclusion level in the diet of juvenile Nile tilapia could be between 0.1% and 0.14% (23.9~33.4 mg kg−1 saponin) as a feed additive to promote growth, enhance the non-specific immune responses and increase disease resistance.

Effects of some dietary crude plant extracts on the growth and gonadal maturity of Nile tilapia (Oreochromis niloticus) and their resistance to Streptococcus agalactiae infection.

A 90-day feeding trial was conducted on the growth performance, feeding efficacy, body indices, various hematological and plasma biochemical parameters, and histopathological examination of the gonads from male and female Nile tilapia fingerlings when fed different crude plant extracts from Cinnamomum camphora, Euphorbia hirta, Azadirachta indica, or Carica papaya at 2 g kg(-1) compared to a control diet. This was followed by a 14-day challenge to Streptococcus agalactiae. All treatments were triplicated, and each treatment consisted of 30 fish. Results showed that C. papaya extracts were the most effective at delaying gonadal maturation to both male and female tilapia, as well as significantly increasing (P < 0.05) growth performance compared to the control treatment. Similarly, dietary C. camphora and E. hirta extracts also significantly improved growth, while no significant growth effect was detected between the A. indica and control treatments (P > 0.05). Further, crude body lipid was lower in the C. camphora, E. hirta and C. papaya treatments, but was only significantly lower for the E. hirta treatment compared to the control. Meanwhile, none of the hematological or biochemical parameters were significantly affected, although plasma ALT was significantly lower for tilapia fed A. indica compared to the control. After the 14-day bacterial challenge, tilapia fed C. camphora supplementation had significantly higher survival, compared to the control, but was not significantly higher than the other supplemented diets. Results indicate that dietary C. papaya extract can significantly promote growth and delay gonadal maturation to both male and female tilapia, while C. camphora was the most effective prophylactic to S. agalactiae and may be a cost-effective and eco-friendly alternative to antibiotics.

Induction of rainbow trout MH class I and accessory proteins by viral haemorrhagic septicaemia virus

Major histocompatibility (MH) class I receptors are glycoproteins which play a critical role during responses to intracellular pathogens by presenting endogenous peptides to cytotoxic T cell lymphocytes (CD8+). To date, little is known about MH class I regulation at the protein level during viral infections in fish. In this study, we characterised the MH class I pathway response to polyinosinic–polycytidylic acid (poly I:C) and upon infection with viral haemorrhagic septicemia virus (VHSV) genotype IVa using the rainbow trout monocyte/macrophage cell line RTS11. A 14-day challenge with VHSV IVa at 14°C demonstrated enhanced expression of the class I heavy chain, β2 microglobulin (β2M) and tapasin, while the expression of other accessory molecules ERp57 and calreticulin remained unchanged. However, when infection occurred at 2°C no change in expression levels of any of these molecules was observed. β2M accumulated in the media of RTS11 over time, however the β2M concentrations were 2 fold higher in cultures infected with VHSV 14 days post infection. Strikingly, when cells were maintained at 2°C the secretion of β2M was significantly reduced in both infected and non-infected cultures. These results indicate that VHSV infection alters the kinetics of β2M release as well as the expression of MH class I and suggests that cellular immunity against VHSV can be compromised at low temperatures which may increase host susceptibility to this virus during the winter.

Comparative study between probiotic bacterium Arthrobacter XE-7 and chloramphenicol on protection of Penaeus chinensis post-larvae from pathogenic vibrios

A strain of Arthrobacter XE-7, isolated from Penaeus chinensis was evaluated for potential use as a probiotic for shrimp post-larvae. In vitro studies demonstrated antagonism against Vibrio parahaemolyticus, Vibrio anguillarum and Vibrio nereis. During the 14-day challenge experiment, the shrimp post-larvae aged 10 days were reared in water with addition of either Arthrobacter XE-7 (10 6 CFU/ml), chloramphenicol (2 mg/l) or the three pathogenic vibrios (10 6 CFU/ml): Controls, (V) pathogenic vibrios alone, (A) Arthrobacter XE-7 alone, (C) chloramphenicol alone, (AV) pathogenic vibrios in combination with Arthrobacter XE-7, and (CV) pathogenic vibrios in combination with chloramphenicol. The surface growth rate of nitrogen and the attenuation rate of bacterium in culture water were detected for the first 7 days, and the cumulative mortality was recorded for the whole challenge experiment. Treatment A had no significant higher survival than the Control. However, Treatment AV produced significantly higher survival than Treatment V ( p < 0.05); Furthermore, it was not significantly lower than those of Treatment CV. Comparable attenuation rate of vibrios was observed in Treatment AV and CV, and it was significantly lower than that in Treatment V ( p < 0.05). In addition, results of the surface growth rate of nitrogen show that the Arthrobacter XE-7 has the nitrification ability to oxidize ammonium to nitrite. Both chloramphenicol and Arthrobacter XE-7 are able to comparably protect the shrimp post-larvae from the pathogenic vibrios. Then, Arthrobacter XE-7 can be regarded as a probiotic bacterium for the culture of shrimp larvae.