Immunomodulatory Effects of Dietary β‐glucan and Vitamin C in Nile Tilapia, Oreochromis niloticus L., Subjected to Cold‐induced Stress or Bacterial Challenge. Issue 4 (August 2015)

• Record Type: Journal Article
• Authors: Barros, Margarida M.; Falcon, Dario R.; Orsi, Ricardo O.; Pezzato, Luiz E.; Fernandes Junior, Ademir C.; Fernandes Junior, Ary; de Carvalho, Pedro L. P. F.; Padovani, Carlos R.; Guimarães, Igo G.; Sartori, Maria M. P.
• Is Part Of: Journal of the World Aquaculture Society. Volume 46:Issue 4(2015)
• Page Start: 363
• Page End: 380
• Publication Date: 2015-08
• Subjects: Aquaculture -- Periodicals; 639.8
• DOI: 10.1111/jwas.12202
• Languages: English
• ISSNs: 0893-8849

Abstract

<abstract abstract-type="main" id="jwas12202-abs-0001"> <title>Abstract</title> <p id="jwas12202-para-0001">To determine the dietary β‐glucan and vitamin C levels that would enable the fish to cope with different stress, 252 tilapia (16.86 ± 0.24 g) were distributed in thirty six 250‐L aquaria and fed experimental diets for 60 d. Diets were supplemented with β‐glucan (0.1, 0.2, 0.4, and 0.8%) and vitamin C (400 and 600 mg/kg diet) and distributed in a factorial design that included a control diet (0 β‐glucan/125 mg vitamin C/kg). After growth performance analyses, a group of 108 fish were subjected to cold‐induced stress and another to <italic>Aeromonas hydrophila</italic> infection. Hematological and immunological parameters were determined before and after the stress. Growth performance was not affected. Red blood cells, hematocrit, mean corpuscular volume, total plasma protein, albumin : globulin ratio and leukocytes, lymphocytes, neutrophils, and monocytes were affected (<italic>P</italic> < 0.05) by stress and/or diets. The control diet resulted in higher post‐infection cortisol (<italic>P</italic> < 0.05). Liver vitamin C was directly proportional to dietary vitamin C (<italic>P</italic> < 0.05). The production of hydrogen peroxide and nitric oxide was also affected by diets and/or bacterial challenge (<italic>P</italic> < 0.05). In total, 0.1–0.2% β‐glucan and 600 mg/kg vitamin C increased fish resistance to stress and 0.8% β‐glucan resulted in reduced immune responses regardless of the vitamin C supplementation level.</p> </abstract>