Optimal dietary carbohydrate to lipid ratio for bullfrog Rana (Lithobates) catesbeiana

Abstract

This study aimed to investigate the optimum dietary carbohydrate/lipid (CHO/L) ratio for bullfrog Rana (Lithobates) catesbeiana. Six isonitrogenous and isoenergetic diets were formulated, containing various CHO/L from 1.20 to 12.11. Bullfrogs were fed six diets for 8 weeks and each diet was tested by three replicates. After the 8 weeks feeding, weight gain and specific growth rate increased significantly as dietary CHO/L ratios decreased, but showed little difference (P > 0.05) as dietary CHO/L ratios ranged from 1.20 to 2.76. Nitrogen retention was significantly affected by CHO/L ratios, and bullfrog fed with CHO/L 6.10 and 1.82 diets showed the lowest and highest nitrogen retentions respectively. Energy retention increased significantly as dietary CHO/L ratios decreased and bullfrog fed the CHO/L at 1.82 and 1.20 diets showed the highest value. Whole‐body lipid and energy levels both increased significantly (P < 0.05) as dietary CHO/L ratios decreased. Moreover, liver lipid content of bullfrog fed CHO/L 1.82 and 1.20 diets were significantly higher than that of other groups. Plasma insulin level significantly increased as the elevation of dietary CHO/L. Malondialdehyde level increased as the CHO/L decreased, and the bullfrog fed the CHO/L 1.20 diet had the highest level. In conclusion, the present results clearly showed the effects of dietary CHO/L ratios on growth; the optimum CHO/L is 2.07 (approximately 22.49% carbohydrate and 10.83% lipid) based on the second‐order polynomial regression analysis of weight gain.

Effect of Protein Rate on the Growth, Feed Efficiency and Composition of Hoplobatrachus Occipitalis (Günther, 1858) Tadpoles’ Carcass in Controlled Medium

“…Growth rate has often been used as physiological criterion for nutritional evaluation in many species. Numerous studies showed the importance of protein needs on survival and growth of R. catesbeiana (Chun- , 2016;Olvera-Novoa et al, 2007;Prapee et al, 1997;Carmona-Osulde et al, 1997), R.esculanta (Tokur et al, 2008, but published studies explaining nutritional needs of H. occipitalis are almost inexistent nowadays. The current study aims to determine the optimal ration of H. occipitalis tadpoles.…”

“…Protein rates in these diets are 20, 30, 40, 45, 50 and 60 g / 100 g respectively (Table 1). According to protein needs of tadpoles Rana catesbeiana belonging in the same order as H. occipitalis (Chun-Xiao et al, 2016;Prapee et al, 1997;Olvera-Novoa et al, 2007;Carmona-Osulde et al, 1997).…”

Effects of guanidinoacetic acid supplementation in all-plant protein diets on growth, antioxidant capacity and muscle energy metabolism of bullfrogRana(Lithobates)catesbeiana

“…However, studies on nutritional requirements of the species are still in infancy. Several studies have been conducted for determination of the optimum dietary protein and lipid levels, protein/lipid ratio, carbohydrate/lipid ratio and dietary methionine requirement of the species (Carmona‐Osalde, Olvera‐Novoa, Rodríguez‐Serna & Flores‐Nava, ; Dornelles & Oliveira, ; Huang, Zhang, Wang, Song & Huang, ; Olvera‐Novoa, Ontiveros‐Escutia & Flores‐Nava, ; Zhang, Huang et al., ; Zhang, Feng et al., ). There are several reports indicating the essentiality of GAA supplementation in plant protein‐based diets for broilers (Heger et al., ; Metwally, Ibrahim & Khater, ; Michiels et al., ; Mousavi, Afsar & Lotfollahian, ; Ringel et al., ; Wang, Shi, Shan & Zhang, ); however, to the best of our knowledge, there is no available research on surveying the effects of GAA inclusion in plant‐based diets for aquatic animals.…”

Effects of different dietary carbohydrate‐to‐lipid ratios on growth, plasma biochemical indexes, digestive and immune enzymes activities of juvenile orange‐spotted grouper Epinephelus coioides

“…Compared with mammals and birds, fish have lower carbohydrate utilization abilities, especially carnivorous fish (Weber & Haman, 1996;Wilson, 1994). Numerous studies have shown the protein-sparing potential of non-protein components (lipids and carbohydrates) in diets (Sun et al, 2018;Zhang et al, 2016;P. Zhou et al, 2016).…”

“…Compared with mammals and birds, fish have lower carbohydrate utilization abilities, especially carnivorous fish (Weber & Haman, 1996; Wilson, 1994). Numerous studies have shown the protein‐sparing potential of non‐protein components (lipids and carbohydrates) in diets (Sun et al., 2018; Zhang et al., 2016; P. Zhou et al, 2016). In the present study, the gross energy of all the diet treatments was similar; however, this did not mean that they provided equivalent values of digestible energy.…”