Glowing turbot embryo with visible energy pathways.

Unlock Your Turbot's Potential: A Guide to Embryo Health and Energy

Kai Mendoza in Science & Nature August 2025 • 4 min read.

"Dive into the fascinating world of turbot development and discover how understanding their energy metabolism can lead to healthier, more productive aquaculture practices."

For many involved in marine aquaculture, ensuring the health and vigor of fish from their earliest stages is paramount. The initial developmental phases are particularly critical, directly impacting year-class strength and overall success. These delicate stages are profoundly sensitive to environmental factors, and the quality of eggs plays a pivotal role in determining larval survival and subsequent performance. Understanding the intricacies of embryonic development is, therefore, not just academic—it's essential for successful fish farming.

Embryogenesis is an energetically demanding process. It relies heavily on a carefully orchestrated series of enzymatic systems that drive digestive physiology and substance metabolism. By studying energy metabolism, researchers can better estimate the nutritional requirements of developing embryos and larvae, optimizing broodstock conditions, and improving overall reproductive success. This knowledge forms the bedrock for informed aquaculture practices.

Considerable research efforts have focused on elucidating these early-life processes in fish. Enzymes, for instance, are not merely catalysts; they act as key indicators of development and predictors of survival. By examining specific enzymes and their activity patterns, scientists can gain invaluable insights into the energy mobilization and metabolic shifts that occur during these formative stages.

Decoding Turbot Energy: A Metabolic Blueprint

Glowing turbot embryo with visible energy pathways.

A recent study meticulously examined the catabolic capacities and energy metabolism in turbot eggs during embryogenesis and yolk-sac larval development. Researchers aimed to map out how turbot embryos manage their energy reserves, focusing on key enzymes involved in breaking down energy fuels like proteins and lipids. The team also investigated how these processes contribute to overall energy production.

The study tracked enzymes like trypsin-like proteases (TRY), crucial for protein breakdown, and triglyceride lipase (LIP), essential for lipid metabolism. Citrate synthase (CS) and lactate dehydrogenase (LDH) were also measured to assess the primary energy production pathways. To understand how turbot mobilize carbohydrates, amino acids, and fatty acids, the researchers measured the enzymes pyruvate kinase (PK), aspartate aminotransferase (AAT), and hydroxyacyl CoA dehydrogenase (HOAD). Ratios of these enzymes were then analyzed to reveal the relative contributions of each energy source.

Key Findings at a Glance:

LIP activity followed a distinct 'low-high-low-high' pattern.
TRY activity decreased to its lowest point during the blastula stage before increasing significantly after hatching.
HOAD, AAT, LDH, and CS activities generally increased as development progressed.
PK activity peaked during the cleavage stage and then declined until hatching.

When researchers examined the enzymatic ratios, they found notable patterns. Both AAT/HOAD and PK/HOAD ratios showed 'high-low' patterns, indicating a shift in metabolic priorities during development. These ratios were highest during the cleavage stage and decreased significantly by two days post-hatching. Further analysis revealed that the PK/AAT ratio decreased from the fertilized egg stage to two days post-hatching, while the PK/CS ratio declined significantly from the cleavage stage to two days post-hatching. Conversely, the HOAD/CS ratio tended to increase as development progressed.

Implications for Aquaculture

These findings suggest a carefully orchestrated shift in energy utilization as turbot embryos develop. Initially, carbohydrates are the primary fuel source, but as development progresses, amino acids and fatty acids become increasingly important. This knowledge could revolutionize aquaculture practices, leading to more tailored and effective feeding strategies. Understanding the energy production pathways—anaerobic versus aerobic—can also inform environmental management within aquaculture systems, ensuring optimal conditions for turbot development and growth. The path to healthier and more sustainable aquaculture lies in understanding these fundamental metabolic processes.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1016/j.aquaculture.2017.09.004, Alternate LINK

Title: Patterns Of Catabolic Capacities And Energy Metabolism In Developing Embryos And Yolk-Sac Larvae Of Turbot (Scophthalmus Maximus L.)

Subject: Aquatic Science

Journal: Aquaculture

Publisher: Elsevier BV

Authors: Xuehong Tong, Lele Yang, Xinhui Tang, Xiaolan Yang, Chengman Bao, Jialian Wang, Ye Zhou, Meixiang Tang

Published: 2017-12-01

Everything You Need To Know

What are the key enzymes involved in energy metabolism during turbot embryogenesis, and what roles do they play?

In turbot embryos, key enzymes like trypsin-like proteases (TRY) facilitate protein breakdown, while triglyceride lipase (LIP) is essential for lipid metabolism. Citrate synthase (CS) and lactate dehydrogenase (LDH) assess primary energy production pathways. Pyruvate kinase (PK), aspartate aminotransferase (AAT), and hydroxyacyl CoA dehydrogenase (HOAD) help understand the mobilization of carbohydrates, amino acids, and fatty acids. Tracking the activity and ratios of these enzymes reveals how turbot manage energy reserves during development.

What specific patterns of enzymatic activity were observed during the study of turbot embryogenesis and yolk-sac larval development?

The study found that LIP activity displayed a 'low-high-low-high' pattern during turbot embryogenesis. TRY activity decreased to its lowest during the blastula stage before significantly increasing post-hatching. HOAD, AAT, LDH, and CS activities generally increased with development. PK activity peaked during the cleavage stage and then declined until hatching. Ratios like AAT/HOAD and PK/HOAD showed 'high-low' patterns, indicating shifts in metabolic priorities.

How do the ratios of key enzymes (AAT/HOAD, PK/HOAD, PK/AAT, PK/CS, HOAD/CS) change during turbot development, and what do these shifts indicate about energy source utilization?

The ratio trends indicate a shift in energy source during turbot development. Initially, carbohydrates are the primary fuel, but as development progresses, amino acids and fatty acids become more important. Specifically, PK/AAT and PK/CS ratios decrease from the fertilized egg to post-hatching, while the HOAD/CS ratio increases as development progresses. These shifts reflect changing metabolic demands as the embryo grows.

How can understanding the catabolic capacities and energy metabolism of turbot embryos be applied to improve aquaculture practices?

Understanding the enzymatic activities and ratios can revolutionize aquaculture practices by enabling tailored and effective feeding strategies for turbot. Knowing when to provide specific nutrients based on the embryo's metabolic stage can optimize growth and survival. Furthermore, understanding aerobic versus anaerobic energy production can inform environmental management in aquaculture systems, ensuring optimal conditions for turbot development. Broodstock conditions and overall reproductive success can be improved by optimizing energy metabolism.

How does understanding energy production pathways impact environmental management in turbot aquaculture systems for sustainable practices?

By understanding the energy production pathways during embryogenesis, aquaculturists can optimize environmental conditions such as oxygen levels and waste removal to favor either aerobic or anaerobic metabolism as needed. For instance, ensuring sufficient oxygen can support aerobic metabolism, which is more efficient. Careful management of these factors can lead to healthier turbot and more sustainable aquaculture practices. This level of understanding will optimize the egg quality leading to increased survival rates.