RESUMEN
The betta (Betta splendens) is a carnivorous ornamental species that requires live food. In this study, we evaluated the growth and survival of Betta splendens fingerlings fed ex-situ biofloc (BFT). A total of 375 fingerlings (8.3 ± 4.1 mg and 0.8 ± 0.14 cm) were distributed into 15-L plastic tanks (n=25), with five replicates for each of the following treatments: (i) exclusive live food (LF100), (ii) exclusive biofloc (BFT100), (iii) live food supplemented with biofloc (LF100-BFT100), and a reduction of 15% (iv) and 30% (v) in live food with biofloc supplementation (LF85-BFT100 and LF70-BFT100, respectively). The fish were fed newly hatched brine shrimp (Artemia spp. nauplii) and/or fresh biofloc, twice daily, over a 16-day experimental period. Dietary supplementation of Beta splendens with ex-situ BFT (LF100-BFT100, LF85-BFT100, and LF70-BFT100) resulted in a similar final weight (P>0.05) compared to exclusive brine shrimp (LF100). Regarding total length, the fish in the LF100-BFT100 group were superior to those in the LF100 group (P<0.05). The LF100 and LF100-BFT100 groups showed survival rates of 100% and 98.4%, respectively, which were not statistically different (P>0.05). For all analyzed variables, fish exclusively fed biofloc (BFT100) exhibited unfavorable performance. These results indicate that dietary ex-situ biofloc supplementation, without reducing the supply of live food, can be an interesting alternative in the rearing of Betta splendens since biofloc improves growth performance and maintains a good survival rate.
Asunto(s)
Alimentación Animal , Animales , Acuicultura/métodos , ArtemiaRESUMEN
The objective of this study was to evaluate reproductive traits in adults of Astyanax lacustris subjected to different spawning inducers. The study involved 240 females (12.54 g ± 2.33 and 7.66 cm ± 0.63 cm) and 240 males (5.83 g ± 0.39 g and 6.14 cm ± 0.64 cm), all at reproductive age. Three different inducers were evaluated: (i) 0.4 pellets of Ovopel®/kg of body weight; (ii) 0.5 ml of buserelin acetate/kg of body weight; and (iii) carp pituitary extract (CPE) (5.5 mg CPE/kg body weight for females and 2.5 mg CPE/kg body weight for males), as well as saline solution (without hormone). The degree-hours for spawning were greater (P<0.05) for the Ovopel® treatment (with 204.93) than in the treatment with CPE (183.2). Ovary weight and gonadosomatic index were higher (P<0.05) in CPE and Ovopel® treatments when compared to buserelin acetate. The number of oocytes per female, absolute and relative fecundity were greater (P<0.05) for Ovopel® and CPE treatments. Fertilization rate was higher (P<0.05) in treatment with buserelin acetate (82.3%) in relation to Ovopel® (72.33%) and CPE (62.40%) treatments, and the highest (P<0.05) hatching rates were achieved with buserelin acetate and Ovopel®. The number of larvae per female body weight was greater (P<0.05) when Ovopel® was used. In conclusion, Ovopel® proves to be a more effective reproductive inducer for induced reproduction of A. lacustris when compared to CPE and buserelin acetate.