Effect of dietary protein:energy ratio on weight gain, body composition, serum glucose and triglyceride levels, and liver function of striped bass

Abstract

A 12 week feeding experiment was conducted with juvenile, full sibling striped bass (Morone saxatilis) to evaluate three practical diets with protein:energy ratios of 26.9 (diet 1), 31.1 (diet 2), 35.7 (diet 3) g protein/MJ energy. Survival was high in all three diets, however, growth in diet 1 and 2 was significantly less than in diet 3. Proximate composition of whole fish indicated that striped bass fed Diet 1, with the lowest level of metabolizable energy but the lowest protein:energy ratio, had significantly higher lipid content compared to the remaining diets. Conversely, diet 3, with the highest level of metabolizable energy and the highest protein:energy ratio, was the only diet with an increased whole body protein content. Serum levels of triglycerides increased significantly in all treatments when compared with pre-experimental levels, but were lowest in diet 3. Serum glucose levels dropped from pre-experimental levels in all treatments except diet 1. A linear increase in both lipids and carbohydrates stored in the cytoplasm of the liver hepatocytes was observed with increasing metabolizable energy content of the diets. Hepatocellular swelling was observed in fish fed all three diets. However, the two lower protein:energy ratio diets caused significantly greater swelling of hepatocytes than did the highest protein:energy ratio diet. These data indicate that similar practical diets with less than 34 g protein/MJ may be inappropriate for juvenile striped bass.

Evaluation of Growth Performance and Whole-body Composition of Juvenile Hybrid Striped Bass Morone chrysops�נMorone saxatilis and Red Drum Sciaenops ocellatus Fed High-protein and High-lipid Diets

“…The linear regression analysis showed a moderate but significant influence of dietary E:P ratio on HSI and IPF ratio of both species. In addition, whole‐body protein of both hybrid striped bass and red drum was significantly influenced by dietary protein level and E:P ratio in this study, which is in agreement with responses of striped bass (Woods et al 1995), hybrid striped bass (Keembiyehetty and Wilson 1998), red drum (Webb and Gatlin 2003), and other fish species such as rainbow trout, Oncorhynchus mykiss (Azevedo et al 2004); chinook salmon, Oncorhynchus tshawytscha (Azevedo et al 2004); Asian sea bass, Lates calcarifer (Williams et al 2003); and Japanese seabass, Lateolabrax japonicus (Ai et al 2004). Lipid in the diet did not appear to influence whole‐body lipid, HSI, or IPF ratio of hybrid striped bass in this study.…”

“…The increasing dietary protein level in the experimental diets showed a strong tendency to increase weight gain; however, this growth improvement could at least partially be influenced by an optimized E:P ratio. An appropriate E:P ratio has been reported by various research groups for hybrid striped bass (Brown et al 1992; Nematipour et al 1992; Keembiyehetty and Wilson 1998) and striped bass (Woods et al 1995). However, the optimal E:P ratio could be influenced by protein quality and energy digestibility, as well as environmental factors such as temperature (Keembiyehetty and Wilson 1998).…”

Nutritional Utilization of Modified Carinata Brassica carinata Meals in Sunshine Bass Diets

“…Rawles and Gatlin () reported an increase in HSI in sunshine bass with increasing levels of dietary soluble carbohydrate, which Woods et al. () previously attributed to fluid accumulation in the liver from the elevated dietary carbohydrate. Fluid accumulation is due to glycogen binding with water (Lebret et al.…”

Performance and immunological responses of rainbow trout ( O ncorhynchus mykiss ) fed bioprocessed plant‐based proteins

“…Fish fed BBPC had an increase in FCR and HSI, along with a reduction in growth, protein efficiency, Fulton's condition factor and fillet yield. An increase in HSI has been associated with higher levels of dietary carbohydrates (Woods, Yust, McLead, & Subramanyam, ) and may also indicate an increase in the amount of energy allocated to removing foreign substances or pollutants from the blood. A decrease in K indicates a depletion of energy reserves and thus inadequate nutrient content or bioavailability.…”