Ability of Juvenile White Sturgeon (Acipenser transmontanus) to Utilize Different Carbohydrate Sources

Abstract

Juvenile white sturgeon were fed isonitrogenous diets containing 27.2% glucose, fructose, maltose, sucrose, lactose, dextrin, raw corn starch or cellulose for 8 wk. Growth, body composition, plasma chemistry (with the exception of glucose), and liver glucose-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49), malic enzyme (EC 1.1.1.40) and isocitrate dehydrogenase (ICDH, 1.1.1.42) activities of sturgeon were significantly (P less than 0.05) affected by the different dietary carbohydrate sources. Sturgeon fed either the maltose or glucose diets had the highest percent energy retained, followed by those fed either the dextrin, raw corn starch or sucrose diets, whereas those fed either the lactose, fructose or cellulose diets had the lowest. Sturgeon fed either the maltose or glucose diets were hyperlipidemic, having twice the amount of plasma total lipid, triacylglycerol and total cholesterol as fish fed the other carbohydrate sources. These two carbohydrate sources were also more lipogenic: maltose- or glucose-fed sturgeon had significantly higher body lipid and liver G6PDH, malic enzyme, and ICDH activities. The poor ability of sturgeon to utilize either sucrose or lactose appears to be due to low intestinal sucrase (EC 3.2.1.48) and lactase (EC 3.2.1.108) activities. Intestinal aminopeptidase (EC 3.4.11.11), maltase (EC 3.2.1.20), sucrase and lactase activities of sturgeon were not affected by feeding different carbohydrate sources for 8 wk.

Effect of feeding strategy and carbohydrate source on carbohydrate utilization by white sturgeon (Acipenser transmontanus) and hybrid tilapia (Oreochromis niloticus X O. aureus)

“…The higher growth performance in sturgeon fed the starch than glucose diet within the CF or MF groups may have been partly the result of the better water stability of the starch than glucose diets. The better utilization of starch than glucose diets by sturgeon, however, did not agree with our previous study (Hung et al, 1989) which showed no difference in body weight increase between sturgeon fed glucose and starch diets. This difference may have resulted from the differences in dietary protein levels and sources, diet formulations, fish sizes and feeding rates between the studies.…”

“…The compromised experimental conditions in the present study deviated from conditions in our previous studies (Hung et al, 1989;Shiau and Lin, 1993). This made comparing present with previous results difficult.…”

“…Proximate composition of the diets was determined by the AOAC method (Jones, 1984) and carbohydrate was analysed by the method of Holm et al (1986). Water stability was determined by submerging 5 g of diet for 2 and 4 min (Hung et al, 1989).…”

“…Common carp, red sea bream (Furuichi and Yone, 1982), tilapia (Anderson et al, 1984), yellowtail (Furuichi et al, 1986) and channel catfish (Wilson and Poe, 1987) grew better when fed a starch than glucose diet. On the other hand, chinook salmon (Buhler and Halver, 1961) grew better when fed a glucose than starch diet, and there was no significant difference in net weight gain between glucose and starch fed white sturgeon (Hung et al, 1989). There is, however, no study that has been conducted under the same dietary treatments to directly compare carbohydrate utilization between fish species.…”

“…There is, however, no study that has been conducted under the same dietary treatments to directly compare carbohydrate utilization between fish species. Furthermore, the differences in carbohydrate utilization among fish species may have resulted from different feeding strategies because only meal feeding was used in the above studies except that Hung et al (1989) used continuous feeding. Hung and Storebakken (1994), indeed, showed that carbohydrate utilization by rainbow trout was affected by both feeding strategy and carbohydrate source.…”