RESUMO
Here we show that selected nutritional feed additives reduce the adverse effects of transport stress on the immune system and hematology of tambaqui. We formulated a control diet to contain normal dietary levels of vitamin E (21.6 mg/ kg diet) and C (143 mg/kg), then we added supra levels of these vitamins (vit E - 264 mg/kg and vit C - 1000 mg/kg) to a second diet. Finally, a third diet was produced to contain similar levels of vitamins from diet 2 with 0.1% beta-glucan supplementation. Four hundred thirty-two tambaquis (20.91 g ± 0.27 g) were randomly assigned to 12 aquaria and fed the diets for 15 days; then, all fish were transported for five h and then returned to the aquaria. Blood samples were collected before and after the transport and at the end of the trial (60 days). Transportation significantly increased blood glucose that returned to baseline levels at the end of the trial. However, cortisol seemed to be unresponsive to the stress. Surprisingly, the stress significantly increased the immunoglobulin level after transport. Additionally, the transport markedly reduced the red blood cell count and leukocyte and lymphocytes counts while increasing the control group's neutrophil number. These effects lasted until the end of the trial in the control group. Supra levels of the vitamins and glucan supplementation prevented the decrease in red blood cell and leukocyte count after the stress. Additionally, beta-glucan supplementation induced lower cortisol levels in all the sampling points. However, the effect on the immune parameters was limited, increasing only the lysozyme activity and serum protein levels in the beta-glucan supplemented group and the group fed only the supra levels of vitamins, respectively. In sum, our results indicated that transport for five h induced a limited effect on stress biomarkers. The use of supra levels of antioxidant vitamins alone or in combination with beta-glucan could restore or prevent the adverse effects of stress on hematology and the immune system.
RESUMO
This study was conducted to evaluate the effect of antinutritional factors of RSB (raw soybean) on hematology and growth performance of Nile tilapia (Oreochromis niloticus). The replacement was made the levels of 0.0, 15.0, 25.0 and 35.0% of the protein in soybean meal (SBM) by the crude soy protein. In this study, the effect of replacing SBM by RSB on haematological profile and growth performance of Nile tilapia were evaluated after 90 days of feeding. Urea activity was evaluated of RSB which indicated the presence of antinutritional factors. The hematological parameters (erythrogram and white blood cell) were evaluated. The parameters of growth performance were also evaluated. RSB affected the weight gain, feed intake and protein retention. Additionally, an increase of neuthrophils count and a decrease of albumin concentration were observed. RSB inclusion in the Nile tilapia diet changed the white blood cell number and negatively affected growth development. However, no effect on erythrogram was observed in this study. We can conclude that although the antinutritional factors present in RSB interfered the growth performance, it is recommended to use the replacement level of RSB below 35%, as it does not affect fish health.
O objetivo do estudo foi avaliar o efeito dietético dos fatores antinutricionais da SC (soja crua) na hematologia e no desempenho produtivo da tilápia-do-nilo (Oreochromis niloticus). Foi realizada a substituição de 0,0; 15,0; 25,0 e 35,0% da proteína do farelo de soja (FS) pela proteína da SC. Neste estudo, foram avaliados o efeito da substituição do FS por SC no perfil hematológico e desempenho produtivo da tilápia após 90 dias experimentais. Foi avaliado a atividade ureática da SC, indicando a presença de fatores antinutricionais. Os parâmetros hematológicos (eritrograma e serie branca do sangue) foram avaliados. Também foram avaliados os parâmetros de desempenho produtivo. A SC afetou o ganho de peso, o consumo de ração e a retenção proteica. Além disso, foram encontrados aumento do número de neutrófilos e diminuição da concentração de albumina. A inclusão de SC na dieta da tilápia alterou o número de células brancas no sangue e prejudicou o desenvolvimento produtivo. No entanto, nenhum efeito sobre eritrograma foi observado neste estudo. Assim podemos concluir que, embora os fatores antinutricionais presentes na SC interferiram no desempenho produtivo, recomenda-se utilizar o nível de substituição da SC abaixo de 35%, por não afetar a saúde dos peixes.
Assuntos
Animais , Ciclídeos/crescimento & desenvolvimento , Ciclídeos/sangue , Inibidores da Tripsina , Glycine max , Urease , Contagem de Eritrócitos/veterinária , Valor NutritivoRESUMO
This study was conducted to evaluate the effect of antinutritional factors of RSB (raw soybean) on hematology and growth performance of Nile tilapia (Oreochromis niloticus). The replacement was made the levels of 0.0, 15.0, 25.0 and 35.0% of the protein in soybean meal (SBM) by the crude soy protein. In this study, the effect of replacing SBM by RSB on haematological profile and growth performance of Nile tilapia were evaluated after 90 days of feeding. Urea activity was evaluated of RSB which indicated the presence of antinutritional factors. The hematological parameters (erythrogram and white blood cell) were evaluated. The parameters of growth performance were also evaluated. RSB affected the weight gain, feed intake and protein retention. Additionally, an increase of neuthrophils count and a decrease of albumin concentration were observed. RSB inclusion in the Nile tilapia diet changed the white blood cell number and negatively affected growth development. However, no effect on erythrogram was observed in this study. We can conclude that although the antinutritional factors present in RSB interfered the growth performance, it is recommended to use the replacement level of RSB below 35%, as it does not affect fish health.(AU)
O objetivo do estudo foi avaliar o efeito dietético dos fatores antinutricionais da SC (soja crua) na hematologia e no desempenho produtivo da tilápia-do-nilo (Oreochromis niloticus). Foi realizada a substituição de 0,0; 15,0; 25,0 e 35,0% da proteína do farelo de soja (FS) pela proteína da SC. Neste estudo, foram avaliados o efeito da substituição do FS por SC no perfil hematológico e desempenho produtivo da tilápia após 90 dias experimentais. Foi avaliado a atividade ureática da SC, indicando a presença de fatores antinutricionais. Os parâmetros hematológicos (eritrograma e serie branca do sangue) foram avaliados. Também foram avaliados os parâmetros de desempenho produtivo. A SC afetou o ganho de peso, o consumo de ração e a retenção proteica. Além disso, foram encontrados aumento do número de neutrófilos e diminuição da concentração de albumina. A inclusão de SC na dieta da tilápia alterou o número de células brancas no sangue e prejudicou o desenvolvimento produtivo. No entanto, nenhum efeito sobre eritrograma foi observado neste estudo. Assim podemos concluir que, embora os fatores antinutricionais presentes na SC interferiram no desempenho produtivo, recomenda-se utilizar o nível de substituição da SC abaixo de 35%, por não afetar a saúde dos peixes.(AU)