Desempenho zootécnico de juvenis do camarão penaeus vannamei alimentados com uma ração comercial repeletizada submetida a diferentes graus de moagem

Abstract

Grinding plays a crucial role in animal feed production, optimizing nutrient absorption by reducing particle size. Proper particle size distribution is essential to meet the physiological needs of animals. This study aimed at carrying out a comparative analysis of the effects of different degrees of ingredient grinding on the growth performance of juvenile Penaeus vannamei. The study was conducted at the Aquatic Organisms Nutrition Laboratory (LANOA) of the Institute of Marine Sciences (LABOMAR/UFC). A commercial grower shrimp feed was subjected to four degrees of grinding and repelletized in the laboratory: (1) feed #01, prepared after being subjected to two consecutive grindings using a 300-μm screen; (2) feed #02, prepared after a single grinding on a 300-μm screen; (3) feed #03, prepared after grinding on a 500-μm screen; and, (4) feed #04, subjected to grinding on a 1,000-μm screen. Juvenile shrimp P. vannamei with 12.53 ± 2.05 g body weight were stocked in 40 tanks of 1.5 m³ under 31 animals/m² (50 shrimp per tank). After 69 days of rearing, final shrimp survival (92.3 ± 5.4%), gained yield (318 ± 62 g/m2), weekly growth (1.04 ± 0.12 g), percent weight gain (182 ± 10%) and feed conversion ratio (2.66 ± 0.84) did not show a statistically significant difference between the experimental treatments. At harvest, shrimp fed with feeds #01 (23.69 ± 1.30 g) and #02 (23.30 ± 1.08 g) had a higher body weight compared to feeds #03 (22.50 ± 1 .88 g) and #04 (21.80 ± 1.01 g). These results show that the degree of grinding of ingredients used in the manufacture of commercial feeds influence the growth performance of P. vannamei juveniles. It is concluded that the species achieves a higher body weight when fed with diets containing ingredients with a greater proportion of particles between 300 and < 250 μm. Feeds with particles from 1,000 to 625 μm, even in low proportions, result in a lower body weight.