Navegando por Autor "SALES, Abner Dias"

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Acesso aberto (Open Access)
Fotoperíodo e frequência alimentar na larvicultura do peixe beta
(FEPMVZ Editora, 2016-08) SALES, Abner Dias; VERAS, Galileu Crovatto; BRABO, Marcos Ferreira; ABRUNHOSA, Fernando Araujo; ALVES, Adriana Xavier; DIAS, Bruno César Brito; CAMPELO, Daniel Abreu Vasconcelos; FERREIRA, M.S.S.
The aim of this study was to evaluate the growth, uniformity and survival of Betta splendens larvae, submitted to different photoperiods and feeding frequency. Four hundred and eighty individuals (4.53mg ± 0.32 and 5.51 ± 0.58mm) were randomly distributed into 48 plastic containers (1L) at a density of 10 larvae/L. A completely randomized design was used, with four replications in a factorial 6 x 2, six photoperiods (0L:24D, 6L:18D, 12L:12D, 16L:8D, 20L:4D, 24L:0D) and two feeding frequencies (two or four times a day). The larvae were fed performed with Artemia nauplii at averaging 800/ larvae/ day, for 15 days. Beta larvae subjected to photoperiod 12L:12D and 16L:8E showed the greatest weight gain (P<0.10), while those fed four times daily had greater length growth and uniformity (P<0.10). However, individuals fed four times daily had lower survival when subjected to photoperiod 16L:8E, 20L:4L and 24E:0D (P<0.10). On the other hand, larvae subjected to a photoperiod of 12L:12D, 16L:8L and 20L:4E showed higher survival rate when fed twice a day (P<0.10). Therefore, with the intention of better growth, uniformity and survival of Betta splendens larvae, it is recommended that the hatchery in this species be done under a photoperiod of 12L: 12D with supply of Artemia nauplii twice daily.
Acesso aberto (Open Access)
Influence of photoperiod on growth, uniformity, and survival of larvae of the Amazonian ornamental Heros severus (Heckel, 1840)
(Universidade Federal do Pará, 2016-07) VERAS, Galileu Crovatto; PAIXÃO, Daércio José de Macedo Ribeiro; BRABO, Marcos Ferreira; SOARES, Lourdes Marília Oliveira; SALES, Abner Dias
The objective of this work was to evaluate the influence of photoperiod on growth, uniformity, and survival of larvae of the Amazonian ornamental fish severum (Heros severus). A completely randomized study was used with five treatments (0L:24D, 6L:18D, 12L:12D, 18L:6D, 24L:0D) and four replicates, with the aquaria as the experimental unit. Two hundred severum larvae (3.20±0.16 mg and 5.60±0.00 mm) were distributed into 20 aquariums of one litre at a density of 10 larvae per litre. For a period of 15 days, feed was supplied four times daily with Artemia nauplii in a proportion of 160 nauplii/larvae/feeding. At the end of the experimental period, growth, uniformity, and survival data were subjected to analyses of variance and significance. Manipulation of the photoperiod showed no change in variables because there was no difference in the growth, uniformity, or survival of severum larvae. Thus, for larvae of this species of up to 20 days of age, the manipulation of the photoperiod is not advantageous due to the possible increase in production costs. Therefore, it is recommended to use the photoperiod close to the natural environment.