The effect of starvation on RNA: DNA ratios and growth of larval striped bass, Morone saxatalis

Abstract

Hatchery reared larval striped bass, Morone saxarilis, 8-days-post-hatching were subjected to various feeding/starvation regimes over a period of 14 days.Batches of larvae from each treatment were sampled over the 14-day period and subdivided for determination of notochord length and RNA:DNA ratio. The best growth was found in fully fed FlOOO larvae (exposed to 1000 Artermia nauplii 1 -'), which reached 8.2 mm after 11 days and 9.6 mm after 14 days. Starved animals after 1 I days had notochord lengths of 4.9 mm.Growth curves from feeding-delayed larvae indicated that animals fed after up to 5 days starvation were capable of complete recovery. FLOO larvae (exposed to 100 Arremia nauplii 1 -') had a slower growth rate than FlOOO larvae, reaching a notochord length of 7.3 mm after 14 days. RNA:DNA ratios over time closely followed notochord growth curves, with clear differences between starved, FlOO and FlOOO larvae being established after only 2 days. Equilibrium RNA:DNA ratios of 3.0 and 2.25 were established in FlOOO and FlOO larvae, respectively, 6 8 days after the beginning of the experiment. The average lag time between a change from the starved to the fed condition and a change in RNA:DNA ratio as determined by the divergence of the nucleic acid curve from the starved condition was 0.66 days.In treatments where starvation followed various periods of feeding, larvae regressed in notochord length such that the final length at 14 days reflected the degree of feeding. RNA:DNA ratios in these animals again closely followed growth curves with a lag time of 0.81 days.It was concluded that RNA:DNA ratios provided very accurate indices of growth in striped bass larvae which were highly sensitive to feeding status.

Effects of food consumption and temperature on growth rate and biochemical-based indicators of growth in early juvenile Atlantic cod Gadus morhua and haddock Melanogrammus aeglefinus

“…Our findings are similar to those of other investigations measuring concentrations of nucleic acids in early (larval and YOY) stages of marine fish (e.g. Buckley 1984, Write & Martin 1985, Malloy & Targett 1994, Rooker & Holt 1996, Kuropat et al 2002. The response time of R:D to changes in feeding regime (~3 d, Fig.…”

“…In early life stages of marine fish, biochemicalbased indicators of growth, including measuring the quantities and/or ratios of nucleic acids (RNA and DNA) and protein in the whole body or specific tissues (e.g. Write & Martin 1985, Malloy & Targett 1994, Rooker & Holt 1996, Kuropat et al 2002, have been used to generate field growth estimates. These indicators have been successfully applied to field-caught cod and haddock larvae (Buckley 1984) and have been measured in larger juvenile cod (Foster et al 1993) but have not been calibrated for age-0 juvenile cod or haddock.…”

Use of RNA: DNA ratios as an indicator of nutritional stress in the American oyster Crassostrea virginica

“…These observations suggest that the RNA:DNA ratio in oysters responds more sluggishly to starvation than in vertebrate systems where significant response times may be as low as 12 h in the case of rat livers (Stocco 1976) or 1 d in fish (Bulow 1970, Wright & Martin 1985.…”

“…RNA serves as the machinery required for protein synthesis and the amounts of RNA present have been shown to be directly related to the rate of protein synthesis (Munro & Fleck 1966, Kayes 1979. Work on larval fish by Buckley (1979Buckley ( , 1980Buckley ( , 1982Buckley ( , 1984, Buckley et al (1984) and Wright & Martin (1985) have shown the technique to be rapidly responsive to changes in growth rate, and capable of providing immediate data on growth rate. These properties render the technique particularly suitable for assessing stress in field populations although prior laboratory calibrating is necessary.…”

Effect of paddy straw and sugarcane bagasse on growth and survival of giant freshwater prawn Macrobrachium rosenbergii (de Man, 1879)

“…High protein content in the gut of the shrimps fed on biofilm was recorded by Tidwell et al (2000). It has been reported that RNA : DNA ratios in body tissues can be used to monitor protein synthesis and growth in fish (Bulow, 1970;Wright and Martin, 1985;Khan and Zafri, 1991). In the present study, higher RNA was recorded in prawns harvested from the substrate based treatments indicating higher protein synthesis and also higher growth.…”