Dietary Folate Requirement Determined for Channel Catfish, Ictalurus punctatus

Abstract

Juvenile channel catfish, Ictalurus punctatus, were fed semipurified basal diets containing 0, 0.2, 0.5, 1.0, 4.0 or 10.0 mg/kg of folic acid or 10 g/kg of succinylsulfathiazole in aquaria for 15 wk. Fish fed the sulfonamide showed higher mortality, lower weight gain, lower thrombocyte counts, higher hemocytoblast and neutrophil counts, and lower liver folate concentrations than did control fish (0 folic acid), indicating that significant intestinal bacterial synthesis of folate occurs in channel catfish. There were positive quadratic regressions of weight gain, hematocrit, erythrocyte and leukocyte numbers, and positive linear regressions of plasma and liver folate on dietary folic acid concentrations. Broken-line analysis showed that the dietary requirements for folic acid for optimum weight gain, hematocrit, and erythrocyte and leukocyte numbers were 1.01, 1.17, 1.12 and 1.15 mg/kg, respectively. Plasma and liver concentrations of folate associated with normal growth and hematopoiesis were 22.9 nmol/L and 20.0 nmol/g, respectively. Ratios of leukocytes and lymphocytes to erythrocytes were maximal in fish fed 4.0 mg folic acid/kg, indicating that immunocompetence may increase as the dietary dose exceeds that required for normal growth. Anemia in folate-deficient channel catfish was characterized by pale livers, spleens, gills and kidneys, and by poikilocytosis, anisocytosis, pyknosis, cytoplasmic clearing, increased numbers of hemocytoblasts, macrocytosis, and binucleated erythrocytes or "spectacle" cells.

Effects of different levels of dietary folic acid on the growth performance, muscle composition, immune response and antioxidant capacity of freshwater prawn, Macrobrachium rosenbergii

“…Our findings agreed with the reports on optimal dietary folic acid requirement of grass shrimp (Shiau and Liu, 1994;Shiau and Chin, 1998;Shiau and Chen, 2000), juvenile (Shiau and Huang, 2001b), rainbow trout (Cowey and Woodward, 1993;Esmaeili and Khara, 2014), Grouper (Lin et al, 2011), channel catfish (Duncan et al, 1993) Niletilapia (Barros et al, 2009), Piglets (Ying et al, 2013) Chinese mitten crab (Wei et al, 2015) and Blunt snout bream fingerlings (Sesay et al, 2016). These present investigation suggested that an enhanced growth by dietary folic acid might be a result of increased feed intake and efficiency in feed utilization.…”

“…Folic acid requirement has been studied in some fish and crustacean species including tilapia (Shiau and Huang, 2001a), green cat fish (Hien and Doolgindachbaporn, 2011), rainbow trout (Cowey and Woodward, 1993), grouper (Lin et al, 2011), channel catfish (Duncan et al, 1993) and penaeids (Shiau and Huang, 2001b). Folic acid deficiency has an adverse effect on fish and crustacean growth and health including signs of macrocytic normochromic anemia, poor growth, anorexia, general anemia, lethargy, caudal fin fragility, dark skin pigmentation, dark coloration and infarction of spleen (Halver, 1980;Shiau and Huang, 2001b).…”

New B vitamin recommendations in fish when fed plant-based diets

“…Megaloblastic anaemia with large fragmented cell nucleus in erythrocytes Atlantic salmon (Sandnes 1994;Waagbø, 2010) Channel catfish (Duncan et al 1993) Coho salmon (Smith 1968;Smith & Halver 1969) Rainbow trout (Kitamura et al 1967) Rohu (John & Mahajan 1979) Changed skin coloration Darker colour than normal Japanese eel (Arai et al 1972) Changed behaviour Abnormal swimming Rainbow trout (Kitamura et al 1967) Lethargy…”

Morphogenesis of blood cell lineages in channel catfish

“…The small lymphoid haemoblast and the basophilic erythroblast depicted by Mahajan & Dheer (1980) as first phases of erythropoiesis have characteristics of cells described here as prolymphocyte and lymphocyte. Haemoblasts of Weinberg et al (1972) and Grizzle & Rogers (1976) as well as the haemocytoblasts in figures of Duncan et al (1993) would be classified here as proerythroblast, basophilic and occasionally as polychromatic erythroblast. Erythroblasts I and II described by Lehmann & Stü renberg (1975) as well as the erythroblast and proerythrocyte of Blüm et al (1988) seemed to be identical with basophilic and polychromatic stages described in the present.…”