RESUMO
This study aimed to investigate the stress response of Sparus aurata specimens fed with nutraceutical aquafeed brewer's yeast (Saccharomyces cerevisiae) and spirulina (Arthrospira platensis). For that purpose, 96 (169.0 ± 2.8 g) animals were distributed randomly in 12 tanks (8 fish per tank, 4 replicates) and divided in 3 groups (D1, casein/gelatin, control; D2, brewer's yeast; D3, spirulina) and fed for 30 days. At the end of this period, fish from two replicates of each experimental diet were submitted to air exposure for 60 s while the fish from the other two replicates were maintained undisturbed (control). Afterwards, samples of blood, skin mucus, and head kidney were collected. The results revealed that after air exposure, cortisol, and glucose levels increased in the groups fed D1 (18.5 ± 2.6 mg/mL; 7.3 ± 0.6 mmol/L, respectively) and D2 (20.0 ± 6.2 mg/mL; 7.7 ± 0.6 mmol/L), but glucose not increased in fish fed D3 (13.7 ± 2.6 mg/mL; 5.5 ± 0.3 mmol/L). Lactate levels increased in all stressed groups, but in D1, its levels were significantly higher. After stress procedure, immunoglobulin M (IgM) levels in mucus increased only in fish fed D3 (0.1901 ± 0.0126 U/mL). Furthermore, there was a reduction in the expression of some genes involved in stress response (coxIV, prdx3, csfl-r, ucp1, and sod in fish fed D2 and D3). csf1 decreased only in stressed fish fed D2. However, cat increased in fish fed with D3. In summary, these findings points to the beneficial effects of spirulina and brewer's yeast to improve stress resistance in aquaculture practices of gilthead seabream.
Assuntos
Dieta/veterinária , Hipóxia/fisiopatologia , Dourada/fisiologia , Estresse Fisiológico , Animais , Aquicultura , Glicemia/análise , Hidrocortisona/sangue , Imunoglobulina M/análise , Ácido Láctico/sangue , Distribuição Aleatória , Saccharomyces cerevisiae , SpirulinaRESUMO
Environmental insults, such as exposure to pathogens, modulate the behavioural coping style of animals to stressors, and repeated exposure to stressful environments may lead to species-specific infection phenotypes. To analyse the influence of stress behavioural phenotypes on immune and metabolic performance, gilthead sea bream (Sparus aurata L.) were first screened for proactive and reactive coping styles. Once characterized, both behavioural phenotypes fish groups were bath vaccinated with bacterin from Vibrio anguillarum, an opportunistic widespread pathogen of fish. Gills and liver were sampled at 0 (control group), 1, 3 and 7 days post-vaccination. Immune-, oxidative stress- and metabolic-related transcripts (il1ß, tnfα, igm, gpx1, sod, cat, lpl, ghr1 and ghr2), metabolic endpoints (glucose, cholesterol and triglycerides), hepatic health indicators (aspartate aminotransferase, alanine transaminase and alkaline phosphatase), oxidative stress status (esterase activity, total antioxidant capacity and total oxidative status) and stress biomarkers (cortisol) were determined. Present results indicate that screening for coping styles in the gilthead sea bream segregated the two distinct phenotypes as expected: proactive and reactive. Results also indicate that under bath vaccination proactive fish show high immune response and lower metabolism, whereas reactive fish show low immune and higher metabolic responses.
Assuntos
Vacinas Bacterianas/farmacologia , Doenças dos Peixes/prevenção & controle , Dourada/fisiologia , Vibrioses/veterinária , Vibrio/imunologia , Animais , Vacinas Bacterianas/imunologia , Comportamento Animal , Glicemia/análise , Doenças dos Peixes/imunologia , Doenças dos Peixes/microbiologia , Proteínas de Peixes/genética , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/imunologia , Brânquias/efeitos dos fármacos , Brânquias/fisiologia , Hidrocortisona/sangue , Fígado/efeitos dos fármacos , Fígado/fisiologia , Dourada/microbiologia , Estresse Fisiológico , Vibrio/patogenicidade , Vibrioses/imunologia , Vibrioses/prevenção & controleRESUMO
It is widely known that ß-glucans and probiotic bacteria are good immunostimulants for fish. In the present work we have evaluated the dietary effect of ß-1,3/1,6-glucan (isolated from Laminarina digitata) and Pdp 11 (Shewanella putrefaciens, probiotic isolated from gilthead seabream skin), single or combined, on growth, humoural (seric level of total IgM antibodies and peroxidase and antiprotease activities) and cellular innate immune response (peroxidase and phagocytic activities of head-kidney leucocytes), as well as the expression of immune-related genes in gilthead seabream (Sparus aurata). Four treatment groups were established: control (non-supplemented diet), Pdp 11 (10(9) cfu g(-1)), ß-1,3/1,6-glucan (0.1%) and ß-1,3/1,6-glucan + Pdp 11 (0.1% and 10(9) cfu g(-1), respectively). Fish were sampled after 1, 2 and 4 weeks of feeding. Interestingly, all supplemented diets produced increments in the seabream growth rates, mainly the Pdp 11-suplemented diet. Overall, Pdp 11 dietary administration resulted in decreased serum IgM levels and peroxidase activity. However, the seric antiprotease activity was increased in fish fed with both supplements together. Furthermore, ß-1,3/1,6-glucan and combined diet increased phagocytic activity after 2 or 4 weeks. At gene level, IL-1ß and INFγ transcripts were always up-regulated in HK but only the interleukin reached significance after 4 weeks in the group fed with ß-glucan. On the contrary, IgM gene expression tended to be down-regulated being significant after 1 week in seabream specimens fed with ß-glucan or ß-glucan plus Pdp 11. These results suggest that ß-1,3/1,6-glucan and Pdp 11 modulate the immune response and stimulates growth of the gilthead seabream, one of the species with the highest rate of production in Mediterranean aquaculture.
Assuntos
Dieta/veterinária , Regulação da Expressão Gênica/efeitos dos fármacos , Glucanos/farmacologia , Imunidade Inata/efeitos dos fármacos , Dourada/fisiologia , Shewanella putrefaciens/química , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes Imunológicos/farmacologia , Ração Animal/análise , Animais , Glucanos/administração & dosagem , Probióticos/administração & dosagem , Probióticos/farmacologia , Distribuição Aleatória , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Dourada/genética , Dourada/crescimento & desenvolvimento , Dourada/imunologiaRESUMO
In the present study, we report the isolation and characterization of seabream Sparus aurata pyloric caeca-duodenal lipase. Optimum activity was found at pH 8.5 and salinity of 50 mM NaCl. Lipase activity was sensitive to divalent ions, and extreme pH values (4, 5, and 12), being more stable at alkaline than acid pH. Optimum temperature was found at 50°C, but lipase was stable at temperatures below 40°C. Lipase has a bile salt sodium taurocholate requirement for increased activity. Gradient PAGE electrophoresis revealed the presence of four isoforms with apparent molecular masses of 34, 50, 68, and 84 KDa, respectively. Pyloric-duodenal lipase was able to hydrolyze emulsified alimentary oils. Results confirm the presence of true lipases in Sparus aurata digestive tract.