Ontogenetic development of digestive enzymes and effect of starvation in miiuy croaker Miichthys miiuy  larvae

Abstract

The ontogenetic development of the digestive enzymes amylase, lipase, trypsin, and alkaline phosphatase and the effect of starvation in miiuy croaker Miichthys miiuy larvae were studied. The activities of these enzymes were detected prior to exogenous feeding, but their developmental patterns differed remarkably. Trypsin activity continuously increased from 2 days after hatching (dah), peaked on 20 dah, and decreased to 25 dah at weaning. Alkaline phosphatase activity oscillated at low levels within a small range after the first feeding on 3 dah. In contrast, amylase and lipase activities followed the general developmental pattern that has been characterized in fish larvae, with a succession of increases or decreases. Amylase, lipase, and trypsin activities generally started to increase or decrease at transitions from endogenous to exogenous feeding or diet changes, suggesting that these enzymatic activities can be modulated by feeding modes. The activities of all the enzymes remained stable from 25 dah onwards, coinciding with the formation of gastric glands and pyloric caecum. These results imply that specific activities of these enzymes underwent changes due to morphological and physiological modifications or diet shift during larval development but that they became stable after the development of the digestive organs and associated glands was fully completed and the organs/glands functioned. Trypsin and alkaline phosphatase were more sensitive to starvation than amylase and lipase because delayed feeding up to 2 days after mouth opening was able to adversely affect their activities. Enzyme activities did not significantly differ among feeding groups during endogenous feeding; however, all activities were remarkably reduced when delayed feeding was within 3 days after mouth opening. Initiation of larvae feeding should occur within 2 days after mouth opening so that good growth and survival can be obtained in the culture.

Changes of Digestive Enzymatic Activity on Yellowtail Snapper (Ocyurus chrysurus) During Initial Ontogeny

“…Artificial diets provide adequate quality in function of digestive enzymes present in larvae, improving survival, growth and resistance of this species (Jiménez-Martínez et al, 2012). Our results are similar to those reported for other species, where the digestive process in fish larvae in alkaline conditions usually begins with the contribution of pancreatic and cytosolic enzymes (Xiu et al, 2009). In this context, the presence of alkaline proteases, trypsin and specific chymotrypsin, detected in the first days following the mouth opening was similar to the results of carnivorous fish such as P. californicus (Alvarez-González et al 2006), P. maculatofasciatus (Alvarez-González et al 2008) and C. undecimalis (Jiménez-Martínez et al, 2012), where the earliest activity corresponds to alkaline proteases, as the acid protease activity is closely related to the occurrence of a functional stomach which takes place later (Moyano et al, 1996;Alarcón-López & Martínez-Díaz, 1998;Zambonino Infante & Cahu, 2001;Alvarez-González et al 2008;Jiménez-Martínez et al, 2012).…”

“…The bottleneck in the commercial culture of this species is a high mortality in the early life stages therefore nutrition studies in larvae and juveniles are vital for a commercial scale production (Moyano, Díaz, Alarcón, & Sarasquete, 1996). Drawbridge, Jiménez-Martínez et al, 2012) considering that the feed efficiency depends on fish physiological capabilities for transforming nutrient intake (Alvarez-González et al, 2006;Xiu et al, 2009;Babaei, Kenari, Nazarí, & Gisbert. 2011).…”

“…Thus, the activity of digestive enzymes from hatching to juvenile period can be used as an indicator of nutritional status in early life stage (Moyano et al, 1996;Álvarez-González et al, 2006;Galaviz et al, 2011;Gisbert, Fernández, & Álvarez-González, 2011;Babaei et al, 2011). Several ontogeny studies on digestive physiology during larviculture have been reported as Moyano et al (1996) in Sparus aurata; Zambonino-Infante and Cahu (2001) in Dicentrarchus labrax; Alvarez-González et al (2006) in Paralichthys californicus, Alvarez-González et al (2008) in Paralabrax maculatofasciatus; Xiu et al (2009) in Miichthys miiuy and Jiménez- Martínez et al (2012) in Centropomus undecimalis; whose concluded that larvae before the first exogenous feeding may already be able to absorb the nutrients from the diet as well as changes in the enzymatic activity of various digestive enzymes is very similar to other strictly carnivorous marine fishes. Additional studies have been conducted on the early development of the Menidia menidia and Odontestes bonarensis digestive system to determine the time of maximum enzyme activity (Toledo et al, 2011).…”

Developmental and moult cycle related biochemical changes in larvae of the spider crab, <i>Maja brachydactyla</i> (Brachyura: Majidae)

“…The effects of early feeding conditions on aquatic organisms are generally assessed with a number of indicators commonly referred to as "physiological condition indices". A variety of morphometrical, histological and biochemical parameters are routinely applied to evaluate condition and feeding history in wild and cultured populations of larval fish (Gisbert et al 2004, Cara et al 2007, Shan et al 2009) and crustaceans (Rotllant et al 2001, Johnston et al 2004, Figueiredo et al 2008.…”

Technical Note Polymorphic microsatellite loci from two enriched genomic libraries for the genetic analysis of the miiuy croaker, Miichthys miiuy (Sciaenidae)

“…High mortality and poor growth have been frequently found during artificial larval rearing, which is hindering the mass production of this fish (Shan et al, 2009). Hence, an important approach to improve this situation is to culture strains of fish with enhanced resistance to some major diseases.…”