ADCP/REP/81/16 - Reproductive Physiology of Teleost Fishes: A Review of Present Knowledge and Needs for Future Research













Table of Contents


by B.I. Sundararaj

UNITED NATIONS DEVELOPMENT PROGRAMME

FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS
Rome, 1981

AQUACULTURE DEVELOPMENT AND COORDINATION PROGRAMME ADCP/REP/81/16

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M-44
ISBN 92-5-101145-1

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© FAO 1981

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Table of Contents


FOREWORD

1. INTRODUCTION

2. REPRODUCTIVE CYCLES AND ENVIRONMENTAL CUES

2.1 Models of teleostean reproductive cycles

2.1.1 Catfish, Heteropneustes fossilis
2.1.2 Rainbow trout, Salmo gairdneri and brook trout, Salvelinus fontinalis
2.1.3 Grey mullet, Mugil cephalus
2.1.4 Common carp, Cyprinus carpio

2.2 Reproductive cycles of other teleost groups

2.2.1 Tilapia
2.2.2 Indian major carps and Chinese carps
2.2.3 Snappers and groupers
2.2.4 Prochilodus sp. and Brycon sp.
2.2.5 Milkfish, Chanos chanos
2.2.6 Miscellaneous teleost species

2.3 Photoperiod-thermoperiod relationship

3. THE HYPOTHALAMUS

3.1 Morphology
3.2 Hypothalamic regulation of gonadotropic function
3.3 Gonadotropin-releasing factors
3.4 Effects of Mammalian Gonadotropin-releasing Hormone in Fishes

4. THE PITUITARY GLAND

4.1 Morphology
4.2 Identification of gonadotrophs
4.3 Immunocytological identification of gonadotrophs
4.4 Pituitary and plasma gonadotropin levels

5. GONADOTROPIC HORMONES

5.1 Isolation
5.2 Chemistry and immunological properties
5.3 One versus two gonadotropins
5.4 Plasma gonadotropin profiles

6. THE OVARY

6.1 Morphology
6.2 Cellular source of steroid hormones
6.3 C18 estrogenic steroids
6.4 C19 and C21 steroids
6.5 Sex recognition and pheromones
6.6 Post-ovulatory follicle

7. HORMONAL REGULATION OF VITELLOGENESIS

7.1 Role of piscine gonadotropins
7.2 Role of mammalian gonadotropins
7.3 Role of estrogenic steroids in synthesis of egg-yolk precursors
7.4 Chemistry of egg-yolk and its precursors

8. HORMONAL REGULATION OF OOCYTE MATURATION AND OVULATION

8.1 Introduction
8.2 Hypophysation

8.2.1 Hypophysation by homoplastic and heteroplastic pituitary extracts
8.2.2 Hypophysation by partially purified and purified gonadotropins
8.2.3 Hypophysation by steroids

8.3 Existence of a steroidogenic relay in gonadotropin-induced maturation
8.4 Source of maturation-inducing steroids: The ovary versus the interrenal
8.5 Hypotheses
8.6 Mechanism of steroid-induced oocyte maturation
8.7 Ovulation
8.8 Ovulating agents other than gonadotropins and steroids

9. THE TESTES

9.1 Morphology
9.2 Cellular source of steroid hormones
9.3 Androgenic steroids
9.4 Sex accessory glands
9.5 Sex recognition and pheromones

10. HORMONAL REGULATION OF SPERMATOGENESIS AND SPERMIATION

10.1 Effects of mammalian and piscine gonadotropins
10.2 Effects of androgens
10.3 Spermiation

11. FEEDBACK ACTIONS OF GONADAL STEROIDS

11.1 Introduction
11.2 Effects of gonadectomy and sex steroid therapy on the hypothalamus and pituitary
11.3 Feedback actions of sex steroids on gonadotropin secretion

12. PRESERVATION OF SPERMATOZOA AND OVA

12.1 Introduction
12.2 Quality of gametes

12.2.1 Spermatozoa
12.2.2 Ova

12.3 Methods of preservation of gametes

13. USE OF SEX STEROIDS IN SEX REVERSAL

14. THE PINEAL

14.1 Morphology
14.2 Pineal and reproduction
14.3 Pineal secretions
14.4 Pineal and gonadal activity
14.5 Role of pineal in the regulation of reproductive cycles

15. APPLICATION OF BASIC RESEARCH TO IMPROVE PROPAGATION OF CULTIVATED SPECIES

15.1 Introduction
15.2 Reproductive cycles and environmental cues
15.3 The Hypothalamus
15.4 The pituitary gland
15.5 The gonadotropic hormones
15.6 The ovary
15.7 Hormonal regulation of vitellogenesis
15.8 Hormonal regulation of oocyte maturation and ovulation
15.9 The testis
15.10 Hormonal regulation of spermatogenesis and spermiation
15.11 Feedback actions of gonadal steroids
15.12 Preservation of gametes
15.13 Use of sex steroids in sex reversal
15.14 The pineal

16. CONCLUDING REMARKS

17. REFERENCES

Table I - A partial list of species selected for large-scale farming in the developing countries of Asia, Africa and Latin America

Table II - Bioassays used in evaluating the gonadotropic potency of pituitary extracts and fractions