Development of fish species new to aquaculture: optimizing reproduction, growth and selection of high performance traits.

水产养殖产量现在占所有水产品消费量的很大一部分。一个成立仅30年的行业出现了令人难以置信的增长。水产养殖科学也是非常新的，尚未解决与该行业相关的许多挑战。例如，与农业不同的是，用于鱼类生产的养殖项目很少。开发水产养殖物种最困难的方面之一是管理和生产高质量的配子，这些配子将产生具有在经济背景下导致“最佳性能”的特征的鱼。蛋的质量是水产养殖中的一个问题，在很大程度上受雌性饮食的控制。确定饮食控制对鸡蛋质量的影响需要大量的空间和时间，特别是对于更大、更长寿的鱼。因此，开发亲鱼饲料是困难、耗时和昂贵的。在胚胎水平上控制营养有可能成为管理鸡蛋质量的一种更具成本效益的方法。我们开发了第一个成功的显微注射/操纵系统来控制活鱼胚胎的卵黄大小。我建议进一步改进这一方法，为亲鱼饲料的开发提供一种快速、廉价的方法。我建议操纵斑马鱼胚胎发育中的必需脂肪酸(EFA)谱。全民教育在鱼类中发挥着各种基本功能。例如，DHA被认为是神经系统、感觉器官和眼睛正常发育的全民教育。我们将通过显微注射/操作DHA和其他必需脂肪酸，如EPA和ARA，来改变鱼卵的脂肪酸组成，以研究它们如何影响斑马鱼的发育、存活和性能特征。这项工作将是制定微注射/操纵方案的第一步，以促进水产养殖亲鱼饲料的开发。鸡蛋通常被视为有限的资源，而精子被认为是无限的。然而，情况并不一定是这样；对于许多鱼类来说，每个繁殖季节只产生有限数量的精子。因此，为了在培养环境中管理配子的使用并了解野生种群的招募，我们需要知道每个卵子受精需要多少精子，精子在水中暴露后的行为和寿命，以及卵子在释放后接受受精的时间。在这项拟议的工作中，我们将重点研究鲟鱼的精子和卵子的相互作用。鲟鱼是世界上最有价值和最濒危的鱼类之一。目前，来自野生捕捞和水产养殖作业的全球鱼子酱供应量很低，由此产生的对这种高价值产品的需求对剩余的野生鲟鱼种群造成了进一步的压力。我和我的学生将重点评估发生在加拿大的三种同时具有水产养殖和保护价值的物种的精子质量和精卵相互作用：短吻鲟鱼(Acipenser Brevirostrum)、湖鲟鱼(A.fulvescens)和白鲟鱼(A.Transmontanus)。这项工作的影响有两个方面。为了生产目的，精子特征的基线数据为选择高质量的雄性亲鱼提供信息，而对精子/卵子相互作用的研究揭示了精子与卵子的比例，有助于有效的配子管理。这项工作还提供了维持野生种群所需的性别比例的洞察力，以及关于生殖策略的信息。进一步发展鲟鱼养殖业不仅会带来经济上的收益，还会减轻野生种群的压力，有助于这些濒危鱼类的保护。3名研究生和7名本科生将通过该研究项目的资助进行培训。

Aquaculture production now represents a significant portion of all fish consumed. There has been unbelievable growth of an industry barely 30 years old. Aquaculture science is also very new and has yet to address many challenges associated with this industry. For example, unlike agriculture, very few breeding programs exist for fish production. One of the most difficult aspects of developing species for aquaculture is managing and producing high quality gametes that will produce fish with traits leading to “optimal performance” in an economic context. Egg quality is an issue in aquaculture and is largely controlled by female diet. Space and time requirements for determining the effect of diet manipulation on egg quality are substantial, particularly for larger, longer-lived fishes. Consequently, developing broodstock diets is difficult, time consuming and expensive. Controlling nutrition at the level of the embryo has the potential to be a much more cost-effective means of managing egg quality. We have developed the first successful microinjection/manipulation system to control yolk size in living fish embryos. I propose to further modify this method, providing a fast and inexpensive approach for development of broodstock diets. I propose to manipulate essential fatty acid (EFA) profiles within developing zebrafish embryos. EFA’s serve various essential functions in fishes. For example, DHA has been implicated as an EFA for normal development of nervous system, sensory organs, and eyes. We will alter the fatty acid profile of fish eggs by microinjection/manipulation of DHA and other essential fatty acids, such as EPA and ARA, to examine how they affect development, survival, and performance characteristics in zebrafish. This work will be the first step in developing a microinjection/manipulation protocol to contribute to development of broodstock diets for aquaculture. Eggs are typically viewed as a limited resource while spermatozoa are considered unlimited. However, this is not necessarily the case; for many fish species only a limited quantity of spermatozoa are produced each breeding season. Therefore, to manage gamete use in a culture setting and understand recruitment in wild populations, we need to know how many spermatozoa are required to fertilize each egg, spermatozoa behaviour and longevity after exposure to water, and how long eggs are receptive to fertilization post-release. In this proposed work, we will focus on sperm and egg interactions in sturgeon. Sturgeon are among the most valuable and endangered fishes in the world. Currently, global supplies of caviar from wild harvesting and aquaculture operations are low and the resultant demand for this highly valued product has put further pressure on remaining wild sturgeon stocks. My students and I will focus on assessing sperm quality and sperm-egg interactions for three species occurring in Canada that are of both aquaculture and conservation interest: shortnose (Acipenser brevirostrum), lake (A. fulvescens), and white (A. transmontanus) sturgeons. Implications of this work are two-fold. For production purposes, baseline data on sperm characteristics informs selection of high quality males for broodstock while research on sperm/egg interactions reveals sperm-to-egg ratios, contributing to effective gamete management. This work also provides insight into sex ratios required to sustain wild populations as well as information on reproductive strategies. Further development of sturgeon aquaculture will not only bring about economic gains, but will also alleviate pressure on wild populations, contributing to the conservation of these imperilled fishes. Three graduate students and 7 undergraduate students will be trained through funding for this research program.