Efeito da frequência alimentar no crescimento de tainhas Mugil liza

• Autor(a) principal: Ribeiro, Halysson Pena
• Data de Publicação: 2017
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da Universidade Federal do Espírito Santo (riUfes)
• Texto Completo: http://repositorio.ufes.br/handle/10/9130
• topic: Marine fish farming; Mugilid; Food frequency; Piscicultura marinha; Mugilídeos; Frequência alimentar; Ciências Ambientais; 55

The objective of this study was to evaluate the effect of feeding frequency and level of feed on zootechnical performance, to analyze the body composition and the profile of polyunsaturated fatty acids (PUFAs) in Mugil liza under different diet for growth maximization. A feed experiment was conducted for 58 days with 450 juveniles (4.96 ± 0.82 g) which were stored in 18 net tanks, installed in 6 glass fiber tanks (volume = 500 l), in a factorial experimental design 3 X 2 (3 feed frequencies and 2 levels of feed), with 3 replicates. The juveniles were fed with commercial feed compound by 40% crude protein and 4000 kcal · kg -1 of metabolizable energy. The average results of the physical-chemical variables of the water were 27.62°C, 6.01mg·L -1 , 35.2g·L -1 and 7.13 for temperature, dissolved oxygen, salinity and pH, respectively. It was observed that survival (100%) was not affected by feed frequency and feed level. The weight gain was higher in the F2N6 treatment (9.81 ± 2.11 g) and did not present a significant difference between 2 and 4 meals per day (p> 0.05). However, raising the feeding level from 3% to 6% B.W. significantly increased the mean weight gain. The specific growth rate was not affected by feeding frequency (1, 2 and 4 meals per day) and raise with the increase of the feeding level (p <0.05), with the highest average for treatments F2N6 (2,08 ± 0,43g · day -1 ) and F4N6 (1,98 ± 0,53g · day -1 ). The Condition Factor did not present a significant difference between the frequencies 1 and 2 meals per day and between 1 and 4 meals per day, but decreased with an increase in frequency from 2 to 4 meals per day. Feeding level contributed to the increase of the condition factor as the percentage of feed offered increased. The highest mean of the condition factor was observed in the F2N3 treatment (1.12 ± 0.058g · cm-3 ). The total biomass was higher (F4N6 = 3.634 ± 12.53g) with increasing food frequency (between 1 and 4 meals per day) and did not differ significantly between 1 and 2 times; and 2 and 4 times. Feeding index significantly affected the total biomass, which raise with increase level. The body composition of juveniles fed 1 and 2 times daily presented significant differences for crude protein, total lipids, mineral residue and dry matter. Analysis of the fatty acid profile found in the juvenile samples of M. liza showed significant differences between the treatments analyzed (1 and 2 meals per day) for polyunsaturated fatty acids (PUFAs). The concentration of PUFAs in relation to the total fatty acids of the sample decreased with the increase in the feed frequency for Linoleic Acid (LA), Alpha Linolenic (LNA), Arachidonic (AA), Eicosapentaenoic (EPA) and Docosahexaenoic (DHA).