Effect of nematode Panagrellus redivivus density on growth, survival, feed consumption and carcass composition of bighead carp Aristichthys nobilis (Richardson) larvae

Abstract

The study aimed to determine the optimum density of freeliving nematodes in feeding bighead carp, Aristichthys nobilis, larvae. In the first experiment, carp stocked at 25 larvae L )1 were fed varying levels of nematodes (50, 75, 100, 125 and 150 per ml) twice a day for 21 days from the start of exogenous feeding. Final body weight was significantly higher (P < 0.05) in larvae fed 125 and 150 nematodes per ml than in those fed 50 and 75 per ml, but survival was low (61.8 and 63.6%, respectively). Survival rate was highest in larvae fed 100 nematodes ml )1 (81.3%). Carcass analysis showed that larvae fed 125 and 150 nematodes ml )1 had significantly lower body protein and higher body lipid than those fed other nematode densities. Carcass ash was similar for larvae fed 50-100 nematodes ml )1 but it decreased significantly at the higher nematode densities. Carp larvae in a subsequent experiment were given 50, 75 and 100 nematodes ml )1 per feeding. Newly hatched Artemia was the control feed. Nematode consumption and growth of the larvae were determined. Larvae were sampled at intervals of 2-4 days and the nematodes in the gut were counted and measured. At each nematode density, the number of nematodes present in the gut of the larvae increased significantly with time. At each sampling day, the number of nematodes in the gut did not differ significantly among treatments (P > 0.05) although it tended to increase with nematode density at day 2 and day 4 but decrease at day 7 onward. The carp larvae consumed significantly shorter nematodes on day 2 and day 4 than on the succeeding sampling days regardless of nematode density. However, the length of nematodes in the gut of the larvae did not differ significantly among the nematode densities. The final body weight of larvae increased with increasing nematode density. The body weight of larvae fed 100 nematodes ml )1 did not differ significantly from that of larvae given Artemia nauplii. Results show that bighead carp larvae should be fed 100 freeliving nematodes per ml at each feeding time.

Panagrellus redivivus mass produced on solid media as live food for Litopenaeus vannamei larvae

“…The introduction of residues of nematode culture medium into the experimental system may also have a detrimental e¡ect on the water quality. The problem of a lower water quality using nematodes as live feed was described by other authors (Wilkenfeld et al 1984;Biedenbach et al 1989;Santiago et al 2004). However, washing nematodes even more thoroughly before being fed to shrimp larvae may reduce the risk of introducing micro-organisms or residues of culture medium.…”

“…There are several studies on the use of mass‐produced P. redivivus in the rearing of first feeding fish larvae (Santiago, Ricci & Reyes‐Lampa 2004; Schlechtriem et al 2004a, b; Schlechtriem, Focken & Becker 2005). The authors concluded that the bag system is suitable for the mass production of nematodes as live food for first feeding larvae of fish and crustacean species, and Ricci et al (2003) stated that it should be applicable for small‐scale live feed producers in developing countries due to its simple technology.…”

Evaluation of an improved RNA/DNA quantification method in a common carp (Cyprinus carpio Linnaeus 1758) larval feeding trial with Artemia , two nematodes (Panagrellus redivivus Linnaeus 1758, Panagrolaimus sp. Fuchs 1930) and dry feed

“…Panagrolaimidae, 'microworms') are commonly used as food for ornamental fish larvae and have been positively tested as larval food in aquaculture fish as well as crustacean species (e.g. Biedenbach et al, 1989;Rottmann et al, 1991;Santiago et al, 2003Santiago et al, , 2004Focken et al, 2006;Sautter et al, 2007). Due to their size, shape and active movement, nematodes are a suitable prey item for fish and crustacean larvae.…”

Cultivo del nematodo Panagrellus redivivus (Goodey, 1945) en un medio de avena enriquecida con Spirulina sp.

“…Las etapas larvales de los organismos acuáticos, en su mayoría, requieren de alimento vivo al inicio de su alimentación exógena; los organismos más comunes que se utilizan en la acuicultura, como alimento vivo son microalgas, rotíferos y nauplios de Artemia (Santiago et al 2004) siendo Artemia la más empleada (Lavens & Sorgeloos 2000), sin embargo, en la acuicultura se requiere tener una mayor gama de organismos que sirvan como alimento vivo, que suplan las necesidades nutricias de los depredadores y que sean de fácil adquisición y bajos costos. Varios estudios han demostrado que el nematodo Panagrellus redivivus es un alimento adecuado para las primeras etapas larvarias de peces y crustáceos (Kahan & Appel 1975, Kahan et al 1980, Wilkenfeld et al 1984, Biedenbach et al 1989, Kumlu & Fletcher 1997, Kumlu et al 1998, Santiago et al 2003, Santiago et al 2004, Schlechtriem et al 2004b.…”

“…Las etapas larvales de los organismos acuáticos, en su mayoría, requieren de alimento vivo al inicio de su alimentación exógena; los organismos más comunes que se utilizan en la acuicultura, como alimento vivo son microalgas, rotíferos y nauplios de Artemia (Santiago et al 2004) siendo Artemia la más empleada (Lavens & Sorgeloos 2000), sin embargo, en la acuicultura se requiere tener una mayor gama de organismos que sirvan como alimento vivo, que suplan las necesidades nutricias de los depredadores y que sean de fácil adquisición y bajos costos. Varios estudios han demostrado que el nematodo Panagrellus redivivus es un alimento adecuado para las primeras etapas larvarias de peces y crustáceos (Kahan & Appel 1975, Kahan et al 1980, Wilkenfeld et al 1984, Biedenbach et al 1989, Kumlu & Fletcher 1997, Kumlu et al 1998, Santiago et al 2003, Santiago et al 2004, Schlechtriem et al 2004b. No obstante que se ha demostrado que este nematodo es excelente fuente de alimento, su utilización no ha sido tan amplia como debiera debido a problemas de producción en alta escala; al respecto, existe el trabajo de Ricci et al (2003) quienes señalan métodos para producir grandes masas de P. redivivus, a bajo costo; también el trabajo de Schlechtriem et al (2002) quienes siguieron el método de Ricci et al (2003) y señalan que obtuvieron producciones de 400 millones de nematodos por kilogramo de medio de cultivo.…”