Maintenance and growth requirements for nitrogen, lysine and methionine and their utilisation efficiencies in juvenile black tiger shrimp, Penaeus monodon, using a factorial approach.
We used a factorial approach to distinguish maintenance from growth requirements for protein, lysine and methionine in the black tiger shrimp, Penaeus monodon. Juvenile P. monodon (initial weight 2.4 g) were fed during 6 weeks one of ten semi-purified diets based on casein and purified amino acids (AA) as N source. The diets contained four levels of crude protein (CP, from 5 to 54 % DM diet) with two levels (% CP) of lysine or methionine (normal or 30 % deficient). Requirements were determined using linear and non-linear regression models. We could thus obtain the first ever data on maintenance (N equilibrium) requirements for CP and AA in P. monodon. CP requirements for maintenance (4.5 g/kg body weight (BW) per d) represented approximately 19 % of the CP requirement for maximal N gain (23.9 g/kg BW per d). The marginal efficiency of utilisation reached a maximum of 38 % for N, 0.77 for lysine and 1.62 for methionine using N gain as response. Lysine requirements were 0.20 g/kg BW per d for N maintenance and 1.40 g/kg BW per d for maximal N gain. Methionine requirements were 0.11 g/kg BW per d for N maintenance and 0.70 g/kg BW per d for maximal N gain. The lysine (5.8 %) and methionine (2.9 %) requirements for maximal N gain, expressed as percentage of protein requirement, agree with literature data using a dose-response technique with smaller P. monodon. The observed interaction between dietary CP and methionine for N gain demonstrates that requirements for indispensable AA (expressed as % CP) cannot be evaluated separately from CP requirements.
Richard
Lenaïg
L
INRA, UMR 1067 Nutrition, Aquaculture and Genomics, F-64310 St-Pée-sur-Nivelle, France.
Blanc
Pierre-Philippe
PP
Rigolet
Vincent
V
Kaushik
Sadasivam J
SJ
Geurden
Inge
I
D000818:Animals; D002364:Caseins; D004044:Dietary Proteins / Q000008:administration & dosage*; D004734:Energy Metabolism; D016014:Linear Models; D016015:Logistic Models; D008239:Lysine / Q000008:administration & dosage*; D008715:Methionine / Q000008:administration & dosage*; D009751:Nutritional Requirements; D033561:Penaeidae / Q000254:growth & development*
D002364:Caseins; D004044:Dietary Proteins; D008715:Methionine; D008239:Lysine