Growth performance and metabolic responses to dietary protein/carbohydrate ratios in pacu (Piaractus mesopotamicus) juveniles

Author(s)

Pereira, Mayara de Moura ^[1] ; Nagata, Mariana Midori ^[2] ; Enes, Paula ^{[3, 4]} ; Oliva-Teles, Aires ^{[3, 4]} ; Urbinati, Elisabeth Criscuolo ^{[5, 1]} ; Takahashi, Leonardo Susumu ^{[2, 1]}

Affiliation

^[1] Univ Estadual Paulista Unesp, Ctr Aquicultura Unesp Caunesp, Jaboticabal Via Ac Prof Paulo Donato Castellane, BR-14884900 Jaboticabal, SP - Brazil

^[2] Univ Estadual Paulista Unesp, Fac Ciencias Agr & Tecnol FCAT Unesp, Dracena - Brazil

^[3] Univ Porto, CIIMAR Ctr Interdisciplinar Invest Marinha & Ambi, CIMAR, Matosinhos - Portugal

^[4] Univ Porto, Dept Biol, Fac Ciencias, Porto - Portugal

^[5] Univ Estadual Paulista UNESP, Fac Ciencias Agr & Vet, Jaboticabal - Brazil

• Document type: Journal article
• Source: AQUACULTURE RESEARCH; v. 51, n. 12, p. 5203-5211, DEC 2020.
• Web of Science Citations: 0

Abstract

Proper inclusion of carbohydrates in aquafeeds can increase protein and lipid retention preventing the catabolism of these nutrients for energy purposes. This research aimed to evaluate performance, metabolic and enzymatic indicators in pacu (Piaractus mesopotamicus) juveniles fed diets with 350 or 400 g/kg starch (S) and 190 or 210 g/kg digestible protein (P) (diets S35P19, S35P21, S40P19 and S40P21 respectively). Overall, the best growth performance was achieved with diet S35P21. Dietary protein and starch levels had no effect on feed intake, feed conversion ratio and protein efficiency ratio. The lowest whole-body protein content was recorded in fish fed the S35P19 diet, while fish fed diet S40P21 presented the highest whole-body lipid content. Regardless of dietary protein level, S40 diets led to higher plasma glucose and triglycerides levels, and higher liver glycogen content. No differences were observed on hepatosomatic index or muscle lipids content. Increasing dietary starch level led to an increase in mesenteric fat index and in liver glucokinase activity, while higher dietary protein promoted a decrease in liver lipid content. Fish fed diet S40P21 showed higher liver glucose-6-phosphate dehydrogenase activity than fish fed the S35P21 and S40P19 diets. Dietary protein and starch levels had no effect on pyruvate kinase and fructose-1,6-bisphosphatase activity. Overall, dietary starch enhanced glycolytic and lipogenic pathways but did not depress gluconeogenic pathway. The results of this study indicate that a diet with 350 g/kg starch and 210 g/kg digestible protein was the most adequate for pacu in terms of growth performance and feed utilization. (AU)

• FAPESP's process: 11/15187-3 - Energy metabolism in juvenile pacu fed diets containing different levels of protein and carbohydrates
• Grantee: Mayara de Moura Pereira
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 10/17755-6 - Growth performance and body composition of pacu juveniles fed diets with different protein-carbohydrate ratio
• Grantee: Mariana Midori Nagata
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• FAPESP's process: 10/15844-1 - Carbohydrates inclusion in diets for pacu and protein sparing effect
• Grantee: Leonardo Susumu Takahashi
• Support Opportunities: Regular Research Grants