Crustacean Egg Production

Armand Kuris

• Publisher: CRC Press
• Year: 2020
• eBook ISBN: 9781000154115
• Edition: 1
• Topic: Biological Sciences
• Subtopic: Biology
• Index: Biological Sciences

This title discusses egg formation, release, and development, variations in life history patterns, population, and fisheries aspects regarding crustaceans.

1. Egg formation, release and development

Egg production, release and activation in the marine shrimp, Sicyonia ingentis

Wallis H. Clark, Jr. & Muralidharan C. Pillai

Department of Animal Science & Bodega Marine Laboratory, University of California, Bodega Bay, USA

ABSTRACT

The decapod Sicyonia ingentis reproduces from the middle of June to the middle of October, during which the females undergo ovarian development and spawning. Multiple spawning without an intervening molt commonly occurs among both field and laboratory held populations. While the details on the vitellogenic stages of oögenesis are largely unknown, post-vitellogenic stages of oöcyte development have been characterized. During the late stages of oögenesis, large jelly-like inclusions (jelly precursor) develop in the oöplasm and eventually become externalized in deep extra-oöcytic crypts around the periphery of the oöcyte. This stage of the oögenesis (cortical specialization phase) occurs prior to germinal vesicle break down (GVBD). GVBD occurs before ovulation and spawning and is an asynchronous event. Prior to spawning, the females exhibit a characteristic prespawning behavior which is correlated with ovulation. The ovulated females can be induced to spawn on demand under laboratory conditions; upon contact with sea water, spawned ova undergo a series of activational events that include: 1) release of the jelly precursor from the extra-oöcytic crypts, 2) formation of a jelly layer, 3) resumption of meiosis, and 4) formation of an extracellular hatching envelope. These events are Mg⁺⁺ dependent in fertilized ova; however, in unfertilized ova both Mg⁺⁺ and Ca⁺⁺ are required.

1 INTRODUCTION

The order Decapoda is divided into two suborders, the Pleocyemata, animals that brood their eggs, and the Dendrobranchiata, whose members are broadcast spawners. Although much is known concerning the reproductive biology of the Pleocyemata, a basic understanding of the reproductive biology of the Dendrobranchiata is still needed. This is somewhat curious, since members of this suborder, especially the Penaeoidea, represent one of the largest wild caught and cultured fisheries in the world. With the exception of older treatises by Hudinaga (1942) and King (1948), most of the available literature deals with techniques for the induction of ovarian growth (i.e. eyestalk ablation as well as nutritional and environmental requirements). While these studies have been important to culturists, for the most part, they have done little towards furthering our understanding of the basic process associated with egg production and early development.

The most thoroughly examined Penaeoidea is the marine shrimp, Sicyonia ingentis (Clark et al. 1984). Extensive knowledge is available on the reproductive biology of males, including studies on male gamete formation (Shigekawa & Clark 1986), sperm structure and sperm activation (for review see: Clark & Griffin 1988). Although less is known concerning the reproductive biology of the female, the reproductive cycle, postvitellogenic ovarian development (Anderson et al. 1985) and egg activation (Pillai & Clark 1987) have been studied. This paper reviews our knowledge of female reproductive biology in this species.

2 BIOGEOGRAPHY

Sicyonia ingentis is the only member of its genus recorded from the west coast of the United States. Its geographic range extends from Monterey Bay, California in the north to Isla Maria Madre, Mexico in the south; in addition it is also reported to be found in the Gulf of California (Perez Farfante 1985). Sicyonia ingentis is commonly found at depths of 61 to 183 m (Carlisle 1969). Females of this species attain a maximum length of 180 mm, measured from the telson to the base of the antenna. Males, on the other hand, are generally smaller and attain a maximum length of 157 mm (Herkelrath 1977). This species is commercially fished in the Santa Barbara Channel off California.

3 FIELD BIOLOGY

The reproductive season of S. ingentis females, sampled off Santa Barbara, California, between 1979-1981, extended from the middle of June to the middle of October. During this period the female population entered anecdysis; ecdysis resumed at the end of the reproductive season. Females exhibited two periods of molt activity, one between late February and early May and a second, more extended period, between late October and early November (Fig. 1). Males did not show the dramatic peaks in molt activity demonstrated by the females, though they did undergo anecdysis during the summer months (Anderson et al. 1985).

Figure 1. Molt activity (based on the frequency of animals with soft exoskeletons) and reproductive activity (based on the frequency of females with advanced stages of oöcytic development) for female S. ingentis. Solid line represents reproductive season and broken line represents the molting season. (Modified from Anderson et al. 1985.)

Plate 1. A; Diagrammatic representation of a gravid female S. ingentis illustrating organization of ovary (OV). The oviducts (OD) pass from lateral lobes of the ovary to ovipores (OP) situated at the base of each third pereiopod. B; Post vitellogenic oöcytes showing jelly-like inclusions (arrows) in the oöplasm. Germinal vesicle (GV) is very prominent, × 260. C; Oöcyte in cortical specialization (CS) phase. Germinal vesicle is still present × 260.

Plate 2. A; Ventral view of female. Ovipores (arrows) located at bases of the third pereiopods. Seminal receptacles (SR) are located in posterior lobes of the thelycum (T). B; The tip of the steel probe being inserted into the right ovipore. C; Ova have been extruded (arrows) from the ovipore as a result of probing, × 3.5. D; The animal after having the right ovipore probed was placed on a beaker containing sea water. Note ova are being spawned from both ovipores. × 0.5 (modified from Pillai et al. 1988).

Plate 3. Transmission electron micrograph of an ovulated ovum (prior to activation). CC-cortical crypt; JP–jelly precursor elements; O–oölemma; VE–vitelline envelope, × 10 000.

Plate 4. A-F; Phase micrographs showing sequence of activational events that a fertilized ovum undergoes upon contacting sea water. A; An ovulated ovum prior to initiation of activation. B-C; The activational events include extrusion of jelly precursor and formation of the jelly layer. D-Ε; Formation of the polar bodies. E; Hatching envelope formation. F; Normal cleavage. CC–cortical crypts; JL– jelly layer, JP–jelly precursor elements, HE-hatching envelope; PB– polar body; SP– sperm, × 90 (from Pillai & Chirk 1987). G-L; Phase micrographs showing the sequence of events (paralleling A-F; above) that an unfertilized ovum of S. ingentis undergoes in sea water. Note the unequal cleavage pattern (L). × 90 (from Pillai & Clark 1987).

Anderson et al. (1985) suggested that females undergo multiple spawns within a single molt cycle. This was based on the high frequency of females in wild population in advanced stages of oöcytic development throughout the reproductive season. This hypothesis was supported by multiple spawning, without intervening molts of laboratory held S. ingentis. The average time between spawns for a single female was 20 days. Multiple spawns without an intervening molt have also been reported for laboratory held Penaeus indicus (Emmerson 1980).

4 EGG DEVELOPMENT

The highly fecund S. ingentis possesses bilateral ovaries which extend from the anterior region of the cephalothorax to the telson. Lateral extensions of the anterior lobes in the cephalothorax course in a ventrolateral direction. Oviducts pass from each anterior lobe to an ovipore situated at the base of each third pereiopod (Pl. 1A). With the exception of the gross morphology, however, the structural organization of the ovary is largely unknown. The vitellogenic stages of oogenesis also remain an enigma. For example, it is not known whether yolk production is autosynthetic, sequestered from extra oöcytic sources (e.g. pinocytotic uptake from hemolymph), or if both mechanisms occur. In the oöcytes of Penaeus sp. both mechanisms may in fact be used (Duronslet et al. 1975). The vitellogenic stages in the oöcytes of S. ingentis appear similar to the vitellogenic stages of Penaeus sp.; however, preliminary data for S. ingentis suggests that, what has been described as autosynthetic yolk production in Penaeus sp., may be the production of a jelly precursor (unpubl. data).

During the late stages of oögenesis, large inclusions appear within the oöplasm (Pl. 1B); these structures fuse with each other, forming rod-shaped bodies which become externalized in deep oöplasmic crypts around the periphery of the oöcytes (Pl. 1C).

The rod-shaped bodies in S. ingentis possess feather-like substructural elements (Pl. 3) similar to that described in Penaeus sp. (Duronslet et al. 1975, Clark et al. 1980, Lynn & Clark 1987). These elements appear to be of oöcytic origin; this is interesting in view of recent evidence suggesting that similar substructural material, of follicular origin, is responsible for extracellular coats of lobster ova (Talbot & Goudeau 1988).

The appearance of jelly-like inclusions around the cortex of penaeoidean oöcytes [corticle specialization phase (CS)] apparently represents one of the last postvitellogenic ...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Table of Contents
• Preface
• Introduction
• 1 Egg formation, release and development
• 2 Variations in life history patterns
• 3 Population and fisheries aspects
• List of authors
• Index