Effects of processing on physical characteristics of diets with distinct levels of carbohydrates and lipids: the outcomes on the growth of pacu (Piaractus mesopotamicus)

Abstract

The use efficiency and feed conversion of extruded and pelletized diets were compared. Eight isoproteic diets (220 g kg )1 digestible protein) were assayed for 90 days in a 2 · 2 · 2 multifactorial design with two carbohydrate levels (400 and 500 g kg )1 ), two lipids levels (40 and 80 g kg )1 ) and two diet processing (pelletization and extrusion) with three repetitions. The growth of Piaractus mesopotamicus fed with these diets and the quality control indices of diets were gauged. The density of extruded diets was lower as carbohydrate level was 400 g kg )1 and lipid 40 g kg )1 . The interaction carbohydrate and diet processing presented higher leaching value for low carbohydrate level in extruded diet. Fish fed with extruded diets presented the best feed conversion and protein efficiency ratio. When high levels of carbohydrate and lipid are combined, the weight gain is impaired. The interaction between diet processing diet and lipid levels resulted in the best fish performance when pelletized diets with 40 g kg )1 lipid or extruded diets with 80 g kg )1 lipid were considered. The protein efficiency ratio increased with the increment of carbohydrates in the pelletized diets. The fish show low tolerance to lipids and a preference for carbohydrate when the lipid productive values are taken into account. KEY WORDS

Effect of different concentrations of protein on the digestive system of juvenile silver catfish

“…The influence of diet processing (extrusion or pelletization) of wheat and corn on the nutritional characteristics of the feeding is also reported. Structural changes on the dietary starch can affect the enzyme activity of amylase as reported for pacu Pyaractus mesopotamicus (Honorato et al, 2009). The amylase activity of jundiá was similar in all sections of the gastrointestinal tract.…”

Effects of dietary carbohydrate level on growth, biochemical composition and glucose metabolism of juvenile sea cucumber Apostichopus japonicus (Selenka)

“…Incorporation of this nutrient may improve the physical quality of feed and protein utilization with respect to protein sparing effect (Azaza et al, 2015;Honorato et al, 2010;Vásquez-Torres and Arias-Castellanos, 2012), reduce catabolism of other nutrients for energy and provide metabolic intermediates for the synthesis of other biologically important compounds to promote growth of aquatic organisms (Hemre et al, 2002;Polakof et al, 2012;Vielma et al, 2003;Ye et al, 2009). On the other hand, excess dietary carbohydrate may lead to poor growth (Li et al, 2013;Ren et al, 2011) and lipid deposition by stimulating lipogenic enzyme activities (Chen et al, 2012;Gao et al, 2010).…”

Carbohydrate molecule size affects the metabolic and digestive dynamics of jundiá (Rhamdia quelen)

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