Duration of co-feeding on the Nishikigoi Cyprinus carpio larvae during weaning from live to inert food in an indoor system

Abstract

This study aimed to evaluate the effects of the co-feeding period (C) on the survival and growth of larvae of nishikigoi Cyprinus carpio, during the weaning period from live to inert food. A total of 1680 larvae with initial weight of 1.33 ± 0.12mg and initial length of 6.0 ± 0.33mm were used. The inert diet used was a commercial ration with 55% crude protein and the live food was the newly hatched nauplii of Artemia franciscana. The experiment was conducted following a completely randomized design with six treatments and four replications. Treatments constituted of: a) LF = supply of live food throughout the experimental period; b) C4 = 6 days of live food + 4 days of co-feeding (inert diet and live food) + 16 days of inert diet; c) C8 = 6 days of live food + 8 days of co-feeding + 12 days of inert diet; d) C12 = 6 days of live food + 12 days of co-feeding + 8 days of inert diet; e) IF = supply with inert diet throughout the experimental period; and f) F = fasting. Our results showed that the co-feeding period influences the survival and growth of the larvae. Survival in the treatment with the longest cofeeding period showed an improvement of over 70% when compared to the shortest period. Further, we noted a doubling of the juvenile weight after 26 days of age. There was a quadratic effect for all parameters, with maximum points ranging between 19.4 and 22.6 days of supply of live food. We concluded that the supply of commercial feed as exclusive food is unworkable in nishikigoi larviculture. RESUMO:Com o objetivo de avaliar os efeitos do período de co-alimentação (C) na sobrevivência e crescimento de larvas de nishikigoi Cyprinus carpio, durante o período de transição de alimentos vivos (AV) para dieta inerte (DI), foram utilizados um total de 1680 larvas com peso inicial de 1,33 ± 0,12mg e comprimento inicial de 6,0 ± 0,33mm. Para a dieta inerte foi utilizada uma ração comercial com 55% de proteína bruta e como alimento vivo, nauplios recém eclodidos de Artemia franciscana. O experimento foi conduzido em delineamento inteiramente casualizado com seis tratamentos e quatro repetições. Os tratamentos foram constituídos por: LF = suprimento de alimento vivo ao longo de todo período experimental; C4 = 6 dias de alimento vivo + 4 dias de co-alimentação (dieta inerte e alimento vivo) + 16 dias de dieta inerte; C8 = 6 dias de alimento vivo + 8 dias de co-alimentação + 12 dias de dieta inerte; C12 = 6 dias de alimento vivo + 12 dias de co-alimentação + 8 dias de dieta inerte; ID = dieta inerte durante todo o período experimental, J = jejum. O período de co-alimentação influencia a sobrevivência e o crescimento das larvas melhorando mais de 70% a sobrevida entre os períodos de co-alimentação mais longos e curtos testados. Além disso, foi verificado um aumento de duas vezes o peso juvenil após 26 dias de idade. Houve um efeito quadrático para todos os parâmetros, com pontos máximos variando entre 19,4 e 22,6 dias de suprimento de alimentos vivos. Também é possível concluir que o fornecimento de alimentação comercial, com...

Technical and economic feasibility of food strategies in the hatchery of Cyprinus carpio (Cypriniformes, Cyprinidae) in a recirculating aquaculture system

“…The low survival averages observed in these two treatments are probably related to the amount of food provided to the larvae, a fact that probably increased intraspecific competition, generating increased mortality. Contrary to what was observed in this experiment, Fosse et al (2018) observed survival of 97.86 ± 1.84% in the cultivation of ornamental carp larvae, using only 150 Artemia nauplii per larvae, but this author has adopted the density of 7 larvae L -1 and does not make clear whether it was carried out proportional correction regarding the number of nauplii offered. In this experiment was used the density of 20 larvae L -1 , and correction of Artemia nauplii quantity offered according to the observed mortality.…”

“…In present experiment it was observed that the carp larvae submitted to the proposed food protocol for treatment 1 were able to feed with powder meal from day 1 of exogenous feeding, as observed by other authors (Bryant & Matty, 1981;Fosse et al, 2018), but presented results of morphological parameters lower than those observed for the other treatments. Differing from what observed in this experiment, some authors working with other inert food formulations in the larviculture of the common carp, achieved good results in morphological parameters using a few basic ingredients, such as yeast and casein (Carvalho et al, 1997;Cahu et al, 1998).…”

“…In the present experiment, the larvae subjected to treatment T4, T5 and T6 presented final weight higher than that observed by Fosse et al (2018). Although these authors had used low stocking density (7 larvae L -1 ) and more extended period of biometrics (10 days) than in the present experiment, larvae from this treatment T4, T5 and T6 showed superior performance.…”

“…Probably the low yield of larvae fed with inert food from the first day of exogenous feeding in this experiment was related to the limited capacity of digestion of the larvae, together with the quality of food provided to the larval stage of this species, as noted by . Fosse et al (2018), working with different feeding strategies on the larval rearing of ornamental carp, also was not observed the good performance of larvae fed exclusively with inert food.…”

“…Nutritional strategies using live food (Cahu et al, 1998), inert (Carvalho et al, 1997) or both (Fosse et al, 2018), have proven effective in larval rearing of different species. However, in general, little attention has been given to the corrections of the total amount of food needed during the cultivation.…”