Application of Effective Day Degrees in the Assessment of Stable Isotope Patterns in Developing Seahorses under Different Temperatures

Valladares, Sonia; Planas, Miquel

doi:10.3390/ani10091571

Cited by 4 publications

(6 citation statements)

References 64 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The results from our study suggest that copepods are more efficiently assimilated by H. guttulatus juveniles than Artemia, at least during the first DAR. Initially (24-48 h), juveniles from both dietary treatments performed similarly, with δ 13 C values showing a trend similar to previous findings [31] but not related to δ 13 C values in prey. Afterwards, the trends diverged, indicating an improvement of food assimilation in both treatments.…”

Section: Discussionsupporting

confidence: 85%

“…The application of stable isotopes as a nutritional tool in aquaculture represents a powerful method to assess the incorporation of nutrients from the diet into consumers [24][25][26] since the isotopic composition of animal tissues is related to that of the consumer's diet, with a slight variation named trophic discrimination [27,28]. The long-snouted seahorse Hippocampus guttulatus Cuvier 1829 is a European species whose rearing has been recently considered [12,15,[29][30][31]. As in other seahorse species, significant improvements in husbandry and rearing techniques have been recently achieved [5].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Nutrient Incorporation in First Feeding Seahorses Evidenced by Stable Carbon Isotopes

Valladares

Planas

2021

Animals

Self Cite

View full text Add to dashboard Cite

Nutritional issues are among the most critical factors in the initial survival of juvenile seahorses. Currently, there is a knowledge gap on the relationship between nutrient assimilation and the effects on initial mortalities and growth. In the present study, the stable isotope approach was used to assess the incorporation of two live preys (Artemia and copepods) in juvenile seahorses Hippocampus guttulatus. The changes in stable carbon isotope (δ13C) values were studied through two feeding experiments: feeding on Artemia or copepods (experiment 1), and shifting feeding from copepods to Artemia (experiment 2). In experiment 1, after 24–48 h of feeding, juvenile seahorses exhibited small but progressive changes in δ13C values towards those of the corresponding diet, indicating that the assimilation of the food offered was progressively enhanced from days 2–3. Similarly, in experiment 2, a diet shifting from copepods to Artemia caused an increase in δ13C values, reflecting a switch towards the isotopically enriched new diet (Artemia metanauplii). Differences in the assimilation efficiency of preys offered are discussed based on growth and survival rates. The enhanced growth performances and survivals achieved when the juveniles were fed on copepods could be related to higher efficient assimilation of copepods compared to Artemia. The present study demonstrates that the consumption and further assimilation of preys by juvenile seahorses could be traced using stable carbon isotopes. The research on nutrient assimilation of juvenile seahorses should enhance our knowledge on nutrient processes in developing seahorses for a better understanding of initial ontogeny in the early life stages of the species.

show abstract

Section: Discussionsupporting

confidence: 85%

Section: Introductionmentioning

confidence: 99%

Nutrient Incorporation in First Feeding Seahorses Evidenced by Stable Carbon Isotopes

Valladares

Planas

2021

Animals

Self Cite

View full text Add to dashboard Cite

show abstract

“…Due to the almost complete exhaustion of yolk reserves in newborn H. reidi [47] and the rapid adaptation to exogenous feeding, the juveniles undergo a fast initial change towards dietary isotopic values (e.g., copepods) [48]. Previous studies have shown that when organisms were provided with a new diet isotopically different from the previous diet, their tissues will eventually reflect the isotopic signature of the new diet [24,36,49].…”

Section: Discussionmentioning

confidence: 99%

Turnover Rates and Diet-Tissue Discrimination Factors of Nitrogen and Carbon Stable Isotopes in Seahorse <em>Hippocampus reidi</em> Juveniles Following a Laboratory Diet Shift

Hernández‐Urcera¹,

Carneiro²,

Planas³

2022

Preprint

View full text Add to dashboard Cite

The initial development of seahorse juveniles is characterized by low digestion capabilities. Stable isotope analysis is an effective tool in studies of trophic food webs and animal feeding patterns. The present study provides new insights for the understanding of growth and food assimilation in early developing seahorses following a laboratory diet switch. The study was performed in early life stages of the seahorse Hippocampus reidi by assessing the influence of diet shift on changes and turnovers in carbon (δ13C) and nitrogen (δ15N) stable isotope in juveniles. Newborn seahorses were fed for 60 days following two feeding schedules (A6 and A11) based initially on copepods Acartia tonsa and subsequently on Artemia nauplii (since days 6 and 11, respectively). After prey shift, we determined δ13C and δ15N turnover rates as functions of change in either body mass (fitting model G) and days of development (fitting model D), contributions of metabolism and growth to those turnover rates, and diet-tissue discrimination factors. Survival, final dry weight and final standard length for diet A11 were higher compared to diet A6. The shift from copepods to Artemia lead to fast initial enrichments in δ13C and δ15N. Afterwards, the enrichment was gradually reduced until reaching the isotopic equilibrium with diet. In most cases, both fitting models performed similarly. The isotopic analysis revealed that 100% of tissue turnover was attributed to growth in diet A11, whereas 19-25% was endorsed to metabolism in diet A6. Diet-tissue discrimination factors were estimated for the first time in seahorse juveniles, resulting in higher estimates for diet A11 (2.9 ± 0.7&permil; for δ13C; 2.5 ± 0.2&permil; for δ15N) than in diet A6 (1.8 ± 0.1&permil; for δ13C; 1.9 ± 0.1&permil; for δ15N). This study highlights the relevance of feeding on copepods and their effect on isotopic patterns and discrimination factors in seahorse juveniles after a dietary shift. Regarding the application of the results achieved to feeding schedules in the rearing of H. reidi, a long period of feeding on copepods during the first days of development is highly recommended.

show abstract

“…Clear differences in the trophic shift were also observed within both intensive farming systems (sea cages and inland tank) (Figure 2). The temperature regime of the growth media and food deprivation due to differences on feeding frequency and quantity of the intensive systems may affect the fish isotopic values [76]. In our experimental work, the metabolic assimilation of the feed was reflected in the muscle of the fish with the characteristic trophic shift, defined as the difference between the mean muscle isotopic signature of a group and that of its respective diet.…”

Section: Discrimination Of Farming Systemmentioning

confidence: 97%

Section: Discrimination Of Farming Systemmentioning

confidence: 99%

The Use of Stable Isotope Ratio Analysis to Trace European Sea Bass (D. labrax) Originating from Different Farming Systems

Tulli

Moreno-Rojas

Messina

et al. 2020

Animals

View full text Add to dashboard Cite

This study aimed to determine whether isotopic ratio mass spectrometry (IRMS) can discriminate farmed European sea bass according to different farming systems and geographic origins. Dicentrarchus labrax of commercial size from three different rearing systems (concrete tank inland, sea cages, and extensive methods in valleys or salt works) were collected at the trading period (autumn–winter). For each farming type, different locations spread over Italy were monitored. Once the fish were harvested, the muscle and feed were sampled. For both muscle and feed, δ13C and δ15N were measured by continuous flow elemental analyzer isotope ratio mass spectrometry (CF-EA-IRMS) with the goal of discriminating samples based on the rearing system. Additional δ2H and δ18O measurements of fish samples were performed by continuous flow total combustion elemental analyzer isotope ratio mass spectrometry (CF-TC/EA-IRMS) to track the geographical origin. The measurements of δ13C and δ15N made it possible to discriminate cultured sea bass from different farming systems (extensive vs. intensive) reared at different geographical sites in Italy. Additional information was obtained from δ18O and δ2H, which enabled the geographical areas of origin of the sea bass farmed extensively and intensively (in cages) to be distinguished.

show abstract

Application of Effective Day Degrees in the Assessment of Stable Isotope Patterns in Developing Seahorses under Different Temperatures

Cited by 4 publications

References 64 publications

Nutrient Incorporation in First Feeding Seahorses Evidenced by Stable Carbon Isotopes

Nutrient Incorporation in First Feeding Seahorses Evidenced by Stable Carbon Isotopes

Turnover Rates and Diet-Tissue Discrimination Factors of Nitrogen and Carbon Stable Isotopes in Seahorse <em>Hippocampus reidi</em> Juveniles Following a Laboratory Diet Shift

The Use of Stable Isotope Ratio Analysis to Trace European Sea Bass (D. labrax) Originating from Different Farming Systems

Contact Info

Product

Resources

About