Early weaning of southern flounder, Paralichthys lethostigma, larvae and ontogeny of selected digestive enzymes

Digestive enzyme activities of turbot (Scophthalmus maximus L.) during early developmental stages under culture condition

“…No pepsin digestion occurs before stomach development (Govoni et al 1986;Zambonino Infante et al 2008). In the present work, pepsin-specific activity was firstly detected at 9 DAH, revealing an early appearance of gastric glands, which is much earlier than many other species such as seabass (Dicentrarchus labrax) at 24 DAH (Zambonino Infante and Cahu 1994), gilthead seabream (Sparus aurata) at 40 DAH (Moyano et al 1996), common pandora (Pagellus erythrinus) at 25 DAH (Suzer et al 2006) and southern flounder (Paralichthys lethostigma) at 37 DAH (Faulk and Holt 2009). A sharp increase in pepsin-specific activity was measured between 31 and 34 DAH, indicating the formation of an almost fully functional stomach coinciding with the histological changes in stomach (data unpublished), while weaning of turbot larvae in the current study occurred at 36 DAH.…”

“…In most marine larvae, due to the lack of a functional stomach, the entire extracellular degradation of ingested prey takes place in the intestine with enzymes derived from the pancreas (Govoni et al 1986;Faulk and Holt 2009). Trypsin is the only pancreatic protease that can activate its own precursor form as well as those of other pancreatic proteases (Corring 1980).…”

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

“…Artemia nauplii, rotifers, Moina , blood worms, Brachionus and copepods are some of the commonly used live feeds in aquaculture. However, associated constraints of live feed production such as high cost, potential risk on disease transmission, required additional infrastructure and manpower create difficulties to hatchery operations (Faulk & Holt,2009 ; Person 1989). Further, some of the live feeds are needed to be enriched with nutrients before feeding as they lack some essential factors required to maintain optimum growth and survival of fish larvae (Sargent et al 1997 ; Aragão et al 2004).…”

Sex determination in southern flounder, Paralichthys lethostigma, from the Texas Gulf Coast

“…Eggs were incubated with gentle aeration in 265 L recirculating larval rearing tanks held at 18°C for the duration of larval rearing. After hatching, larvae were reared as described in Faulk and Holt (2009) through metamorphosis (Daniels, 2000).…”