Evaluation of weaning performance of California halibut (Paralichthys californicus) larvae using growth, survival and digestive proteolytic activity

Abstract

This study evaluated weaning success of California halibut, Paralichthys californicus, larvae onto a microdiet at various stages of development utilizing growth, survival and digestive enzyme activity. Weaning onto a microdiet was evaluated at 16, 26, 36 and 46 days posthatch (dph). Alkaline and acid proteases and leucine aminopeptidase activities were measured after weaning and compared between the weaned treatment and Artemia‐fed controls. Survival was significantly lower in the microdiet‐fed treatments compared to the control groups. Growth was significantly reduced in all weaning treatments compared to the control, except for the 46 dph group. No differences in enzyme activities were detected between treatment and diet at 16 and 26 dph; however, activities were higher for the microdiet‐fed larvae at 36 and 46 dph. This study demonstrates that California halibut larvae possess a differentiated and effective digestive system early in development and can be weaned with relative success (>40% survival) before completion of the metamorphosis (i.e., 36 dph). The lack of weaning success at an early date cannot be entirely because of the absence of a functional stomach but could be related to, among other factors, the low‐microdiet ingestion rates observed and higher leaching of smaller microdiets.

Sudden weaning of angel fish pterophyllum scalare (Lichtenstein) (Pisces; Cichlidae) larvae from brine shrimp (Artemia sp) nauplii to formulated larval feed

“…It was further indicated by the orange coloured larval digestive tract a few minutes after feeding. Low ingestion rate of dry feeds and leaching nutrients from dry feeds have also been highlighted as factors behind the poor growth in fish larvae fed dry feeds (Muguet et al 2011). Moreover, physical properties of feeds (Sarkar et al 2006), developmental stage specific nutritional requirement of larvae are also responsible for the poor growth of larvae exclusively fed formulated feeds (Flüchter 1982).…”

“…Therefore, weaning larvae onto dry formulated diets at their early stage provides economical and practical benefits to hatchery operations. Different weaning protocols with a varying degree of success have been reported in aquaculture literature for both freshwater and marine fish species (Hung et al 2002 ; Bonaldo et al 2011 ; Muguet et al 2011 ; Wang et al 2009 ; Ballagh et al 2010). …”

Improving co-feeding strategies for Neotropical green terror cichlid (Aequidens rivulatus ) larvae with lecithin-enriched Artemia franciscana nauplii: Effects on survival, growth performance and body composition

“…The poor growth performance of fish larvae in groups that used long period time of commercial food could be due to poor ingestion by fish, low digestibility, low nutritional value and leaching nutrients (Lazo, Dinis, Holt, Faulk, & Arnold, 2000). Meanwhile, the absence of active stomach and inadequate digestive enzymes of larvae have been reported as a cause of the failure of commercial foods to live food, wherever the exogenous enzymes in the digestion of live prey can be useful (Muguet et al, 2011). Besides that, Kolkovski, Tandler, and Izquierdo (1997) noted that Artemia nauplii through chemical and visual stimulants had effect on the ingestion and metabolization of formulated foods during co-feeding.…”

“…Co-feeding (i.e., combining live feed and artificial feed) in the early stages of larval development, improves nutritional conditions of the larvae and helps larvae to accept the formulated diet when the live feed is withdrawn, as a result, the duration of feeding on live feed is reduced (Rosenlund, Stoss, & Talbot, 1997). Replacement live feed with formulated diets has been reported with varying degrees of success in aquaculture literature, for both marine and freshwater aquatic species (Bonaldo et al, 2011;Engrola et al, 2007Engrola et al, , 2009Muguet, Lazo, Conklin, & Piedrahita, 2011).…”

Weaning methods using formulated feeds for snakehead ( Channa striata and Channa micropeltes ) larvae

“…Bengtson, Lydon & Ainley ; Ryan, Smith, Collins & Turchini ; Andrade, Nascimento, Conceição, Linares, Lacuisse & Dinis ). Most recently, for a variety of freshwater and marine species, work has focused on age at start of weaning (Parma, Bonaldo, Massi, Yúfera, Martínez‐Rodríguez & Gatta ; Mata‐Sotres, Lazo & Baron‐Sevilla ), digestive enzyme activity (usually also a function of age) (Muguet, Lazo, Conklin & Piedrahita ; Palińska‐Żarska, Żarski, Krejszeff, Nowosad, Biłas, Trejchel, Brylewski, Targońska & Kucharczyk ), diet types (Hauville, Zambonino‐Infante, Bell, Migaud & Main ; Pantazis, Benekos & Papadomichelakis ), abrupt vs. phased transition (Colburn, Walker & Berlinsky ; Liu, Zhu, Lei, Yang, Han, Jin & Xie ), fish size and stocking density (Policar, Stejskal, Kristan, Podhorek, Svinger & Blaha ), and photoperiod and ration (Wocher, Harsányi & Schwarz ). Clearly, weaning success is a function of many factors (Trabelsi, Gardeur, Teletchea & Fontaine ).…”