PresentationPDF Available

CONTROL OF MATURATION AND SPAWNING OF SHELLFISH AND CRUSTACEA BY HORMONE TREATMENT

Authors:

Abstract

Student Assignment (Ph.D Course)
CONTROL OF MATURATION AND SPAWNING OF SHELLFISH AND CRUSTACEA
BY HORMONE TREATMENT
Aulia Deni
Student ID : 202356096
Department of Fisheries Biology
Pukyong National University
Reproduction Control of Aquatic Animals
Busan, 23rd November 2023
Presentation File
Introduction
Control of Maturation and Spawning of Shellfish
and Crustacea by Hormone Treatment
CONTENTS
Control of Maturation and Spawning of
Shellfish by Hormone Treatment
Control of Maturation and Spawning of
Crustacea by Hormone Treatment
Summary
World Population & Food Demand 1Introduction
Sources: Essential Protein Trade & Shipping News, 2022 Sources: Global Seafood Alliance, 2019
Aquaculture vs Capture Fisheries 1Introduction
WORLD CAPTURE FISHERIES AND AQUACULTURE PRODUCTION
Sources: FAO (2022)
Sources: GAA (2019)
Exports of Aquatic Products By Value
Source: FAO. 2022. The State of World Fisheries and Aquaculture 2022. Towards Blue
Transformation. Rome, FAO. https://doi.org/10.4060/cc0461en
Crustacea and Mollusca Production 1Introduction
Whiteleg shrimp,
Penaeus vannamei
Red swamp crawfish,
Procambarus clarkii
Chinese mitten crab,
Eriocheir sinensis
Giant tiger prawn,
Penaeus monodon
Giant river prawn,
Macrobrachium rosenbergii
Indo-Pacific swamp crab,
Scylla serrata
Oriental river prawn,
Macrobrachium nipponense
Green mud crab,
Scylla paramamosain
Cupped oysters,
Crassostrea spp
.
Japanese carpet shell,
Ruditapes philippinarum
Scallops nei,
Pectinidae
Sea mussels,
Mytilidae
Constricted tagelus,
Sinonovacula constricta
Pacific cupped oyster,
Magallana gigas
Blood cockle,
Anadara granosa
Chilean mussel,
Mytilus chilensis
12%
58%
Seed Production in Aquaculture 1Introduction
Limited supply of mud crab (
Scylla serrata
) seeds
and high mortality rates (Apine
et al
., 2023); lack of
mussel seed/spat (Avdelas
et al
., 2021)
hatchery production : maturation and
spawning can be controlled, availability
round the year, and uniform size
There are three systems to obtain seed (spat)
Slow gonad development will extend the breeding
cycle, while rapid gonad development will result
in the inbreeding between the new-born animals
(Jin
et al
., 2022)
wild harvest : natural supply, large
variations and cannot always match the
increasing demand
use of suspended collectors : requires
labour and the collection offshore implies
higher cost
Breeding Technology
Technological innovation of culturing an animal
with an intent of enhancing its reproduction
(sexual maturity) and increased production
(number of seeds produce). The goal of
breeding aquatic species has gone beyond the
mere objective of just increasing food
production and quality, to providing sustainable,
productive, and more environmentally friendly
approaches (Azra
et al
., 2022).
Life Cycle and Growth 2Maturation &
Spawning Shellfish
Life cycle of the eastern
oyster,
Crassostrea virginica.
(Wallace
et al
., 2008)
The developmental stages of the calico
scallop,
Argopecten gibbus
, which take place
within a hatchery (FAO, 2004).
https://www.fao.org/3/y5720e/y5720e07.htm
The life history stages of mussel
Dreissena
polymorpha
(Martinez, 2020)
The life-cycle of the abalone
Haliotis
tuberculate
. Scale bars 100 m (larval stages),
100 mm (juvenile and adult stages) (Jardillier
et al
., 2008)
Anatomy and Reproduction Organ 2Maturation & Spawning
Shellfish
Main internal anatomical
features of the Cortez
oyster
Crassostrea
corteziensis
(Lodeiros
et al
., 2020)
Gross anatomy of an adult
female scallop from Greenland
(Bach
et al
., 2014)
The different soft parts, including foot, of female (left; gonadal tissues in
orange colour) and male (right; gonadal tissues in creamy colour)
individuals of
Perna viridis
(Yap
et al
., 2016)
Anatomy of abalone
digestive system
(Frederick
et al
., 2022)
Spawning Techniques 2Maturation & Spawning
Shellfish
List of spawning induction techniques and methods
(Nowland
et al
., 2021)
Technique
Method
Physical shock
Emersion
Increased temperature and reduced salinity
Chemical induction
Addition of sperm
Addition of sperm extract
Physical and chemical combination
Serotonin
Reduced salinity and addition of sperm
Physical removal of gametes
Strip spawning
An adult male hard clam releasing sperm into
the water (heating), and B) stripping sperm
from male gonads to add to spawning water
(Creswell et al., 2021)
Administration with emulsion containing
py-GnRH peptide into scallop gonad. A) Shells
clamped with clothespin to expose the gonad
for injection with emulsion. B) Schematic
diagram indicating the position of injection
(Nagasawa et al., 2015)
Hormone Treatment in Bivalved 2Maturation & Spawning
Shellfish
The actions of endogenous hormones involved in ovarian maturation and spawning in commonly studied bivalved
Hormone Injection - Serotonin 2Maturation & Spawning
Shellfish
Intramuscular serotonin injection triggered
spawning in four males (22 %) within 38 min
and no further oysters spawned up to 4 h
post-injection (Nowland
et al
., 2021).
Hormone Injection - Serotonin 2Maturation & Spawning
Shellfish
Spawning percentages of Lake Mead
Dreissena rostriformis bugensis
under laboratory conditions under serotonin, temperature shock and
gonad slurry treatments
Spawning percentages of Lake Mead
Dreissena rostriformis bugensis
under laboratory conditions for various serotonin concentrations
Dose response relationship exists between
serotonin concentration and spawning response,
and that consistent spawning of both males and
females is observed following exposure to
serotonin at concentrations at or above 10-4 M
(Schwaebe
et al
., 2013).
Hormone Injection Sex Steroids 2Maturation & Spawning
Shellfish
Acute effects of estradiol injection
on spawning latency and on the
number of gamete released
Effects of estradiol injection on
5-HT-induced spawning.
The effects of estradiol on spawning
latency and on the number of gamete
released
Acute effects of testosterone
injection on spawning latency and
on the number of gamete released
Effects of testosterone injection on
5-HT-induced spawning.
The effects of testosterone on
spawning latency and on the number
of gamete released
Females Male
Sex steroids provide alternative
spawning inducers, especially
when combined with serotonin
Hormone Injection Estradiol-17β2Maturation & Spawning
Shellfish
Five gonadal states were used to classify eastern oysters collected in
August 2006 and treated with estradiol17β: indifferent ( ), early
development ( ), late development ( ), spawning ( ), and advanced
spawning and gonadal regression ( )
The stages of oysters treated with 150 ng of
estradiol-17β was significantly different
from the other treatments (Burnside, 2010)
Hormone Injection GnRH 2Maturation & Spawning
Shellfish
LH (luteinizing hormone) is also one of the gonadotropic
hormones, which plays a role in stimulating
ovulation and sex steroid hormone production
Estrogen, is one of the sex steroid hormones produced
mainly from the follicular cells of the ovary
Effect of synthetic
H. asinina
GnRH (HasGnRH) on LH levels in the
hemolymph (A) and the cerebral and pleuropedal ganglia (B) of
H. asinina
during the mature phase (ng/g BW)
Effect of synthetic
H. asinina
GnRH (Ha
s
GnRH) on estrogen levels in the
hemolymph (A) and ovary (B) of
H. asinina
during the mature phase
The highest levels of LH and estrogen were also
observed in the 250 ng/g BW GnRH-treated
group. GnRH may act as a key messenger which
possibly activate estrogen release in the ovary
(Nuurai
et al
., 2020)
Life Cycle and Morphology 3Maturation & Spawning
Crustacea
The life history of shrimp
involves a migration of
adults offshore where
fertilized eggs are released
and develop (Jill
et al
., 2015)
Generalized stages in the life
cycle of portunid crabs
(Tweedley
et al
., 2017)
Anatomy of
Litopenaeus vannamei
(Edisson
et al
., 2020)
Top view of adult mud crab
indicating major external parts
(Quinitio and Parado, 2003)
D
B
C
A
B
AC
D
Crustacea Growth 3Maturation & Spawning
Crustacea
Life phase of mud crab and sexual dimorphism during mud crab growth
(Hidir
et al
., 2021)
Show life cycle of shrimp (Khushbu
et al
., 2022)
Reproduction Organs 3Maturation & Spawning
Crustacea
Crustaceans are mostly unisexual and can be easily distinguished
into the male and female by morphology (Pamuru, 2019)
Male and female crab
reproductive morphology
(Nagaraju, 2011)
External reproduction organs in male and female shrimp, thelycum is present between
pereopods IV & V and petasma in the 1st pleopod (Dineshbabu, 2014)
The location of various endocrine centres in mud crab (Hidir
et al
., 2021)
Shrimp internal
anatomy
(https://aquariu
mbreeder.com)
Maturation Stages of Shrimp 3Maturation & Spawning
Crustacea
Different maturity stages of gonads in shrimp (Dineshbabu et al., 2014)
Maturity stages based on the colouration of ovary (Dineshbabu
et al
., 2014)
Stages
Immature
The
ovary is thin, translucent and unpigmented
confined to
posterior part of cephalothorax and abdomen
Early maturing
Size of the
ovary increases
, anterior lobes further develop
and extend forward in the cephalothorax; the middle lobes
and rudiments of their lobule develop. The posterior lobe
increases in girth. The general
colour of the ovary is
yellowish.
Late maturing
The ovary develops further, the anterior, middle and
posterior lobes fill the cephalothorax completely. The
ovary is generally
orange in colour, some times with
branched brownish chromatophores distributed over the
surface.
Ovary is clearly visible through the exoskeleton.
Mature
The ovary is very clearly visible through exoskeleton.
The
anterior and middle lobes are well developed. The
colour
of the ovary is
brownish orange. Due to the fullness of the
ovary, the lateral lobules of the middle lobe get folded and
occupy the entire space available in the cephalothorax
Spent
After extrusion of ova, the gonad reverts almost
immediately to immature condition. The ovarian lobes are
flaccid and appear whitish. The ovary contains ova which
are
similar to those in immature stage
Maturation Stages of Crab 3Maturation & Spawning
Crustacea
Visual identification of maturity stages in female crabs (Dineshbabu
et al
., 2014)
Ovary Stages of
Scylla olivace
(Muhd-Farouk
et al
., 2016)
Stages
Immature
colour
Maturing
darso-ventrally, with almost covering the
colour turn to yellow and later to orang. Maturing
Matured
dorso-ventrally, with entirely covering the
colour turn into brown.
Spent
Stages
Immature
A
Stage
-
1 ovary (creamy white)
Maturing
B
C
Early Stage
-2 ovary (yellow)
Stage
-3 ovary (orange)
Matured
D
Stage
-4 ovary (red orange)
Spent
A
Stage
-
1 ovary (creamy white)
Spawning of Shrimp 3Maturation & Spawning
Crustacea
Courtship and mating behavior of
Penaeus monodon
(Shampa
et al
., 2017)
Mating and copulation in Penaeidae shrimps
Litopenaeus setiferus
(Becker and Bauer, 2020)
Penaeus monodon
Litopenaeus setiferus
Phase
1 a
Female above
-male below in parallel swimming
2 b
Male turns ventral side up and attaches to female
3 c
Male turns perpendicular to female
4 d
Male curves body around female and flicks head and
tail simultaneously
Phase
1 a
male chases female up in the
water column
2 a
courtship swimming
3 b,c
copulation
4 d
copulation
Hormone in Crustaceans 3Maturation & Spawning
Crustacea
The effect of eyestalk factors on reproduction in crustaceans
(Nagaraju, 2014).
CHH, crustacean hyperglycemic hormone; MIH, molting inhibiting hormone; VIH,
vitellogenesis inhibiting hormone; GIH, gonad inhibiting hormone; MOIH,
mandibular organ inhibiting hormone; 5-HT, 5-hydroxytryptamine; OA,
octopamine; SP, spiperone; DA, dopamine; Leu-enk, leucine-enkephalin; Met-
enk, methionine-enkephalin. Green arrows indicate positive influence; red
arrows indicate negative regulation; purple arrow indicates either positive or
negative regulation.
Summary of role of hormones in sexual dimorphism of mud crab
(Hidir et al., 2021)
T, testosterone; AGH: androgenic gland hormone; CFSH, crustacean
female sex hormone; LH, luteinizing hormone; P4, progesterone: P5,
pregnenolone; E2, oestradiol; MF, methyl fernasoate; VIH,
vitellogenesis-inhibiting hormone; 5-HT, serotonin; DA, dopamine.
Green arrows indicates positive regulation or stimulation; red arrows
indicates negative regulation or inhibition feminization because the
hormones were the key regulator of sexual differentiation in mud crab
Hormone Regulation 3Maturation & Spawning
Crustacea
The products of Y-organs and mandibular organs called
ecdysteroids and methyl farnesoate (MF) respectively and gonad
stimulating hormone (GSH) are non-eyestalk hormones involved in
the regulation of ovarian maturation
The positive regulators are MF, ecdysteroids and GSH, and the
negative regulators are VIH/GIH and MOIH. Some factors like
CHH, MIH, biogenic amines and opioids are found to be having
both the actions
The hormones of eyestalk such as CHH, VIH/GIH, MIH, MOIH and
other peptides are collectively called as CHH-family peptides
An illustration of factors and hormone regulating
reproduction in crustaceans (Amankwah
et al
., 2019)
CHH = Crustacean Hyperglycemic Hormone,
MIH = Molt-Inhibiting Hormone,
MOIH = Mandibular Organ-Inhibiting Hormone,
VIH = Vitellogenesis Inhibiting Hormone,
RCPH= Red Pigment Concentrating Hormone,
MF = Methyl Farneosate,
GSH = Gonad Stimulating Hormone Schematic diagram of the negative regulation
of vitellogenesis in decapod crustaceans
(Wilder, 2019)
The X-organ/sinus gland complex
is a tissue formed by a collection
of neurosecretory cells and also
produces the CHH-family peptide
group
Eyestalk Ablation 3Maturation & Spawning
Crustacea
Removal of eyestalk eliminates the synthesis and
release of eyestalk gonad inhibitory, which promotes
maturation (Pamuru, 2019)
Eyestalk ablation has been employed to induce
reproductive maturation in crustacean.
Besides the GIH evidence, another hypothesis
suggests that removing eyestalk also reduces light
intensity and thereby inducing ovarian maturation
(Uawisetwathana
et al
., 2011)
The proposed scheme to induce ovarian
maturation by eyestalk ablation in
P.
monodon
(Uawisetwathana
et al
., 2011)
.
GnRH: gonadotropin-releasing hormone;
GIH: gonad inhibiting hormones;
VIH: vitellogenesis inhibiting hormones;
GV: germinal vesicle;
GVBD: germinal vesicle breakdown.
GnRH activates the calcium signaling pathway resulting
in increased levels of intracellular calcium ion through
the GnRH signaling and calcium signaling pathways,
which subsequently activates folliculogenesis, estradiol
and progesterone production in ovary
The previtellogenic oocytes were induced
early by activation of the gonadotropin-
releasing hormone (GnRH) signaling
pathway and the calcium signaling pathway
Inhibition of gonad- or vitellogenesis- inhibiting
hormones (GIH or VIH) upon eyestalk ablation.
Eyestalk ablation releases gonad- or
vitellogenesis- inhibiting hormones (GIH or VIH)
allowing a synthesis of yolk protein
Progesterone may then induce progesterone-mediated
oocyte maturation process from oocyte stage 1 to 4
Mechanism of Action
The Technique of Eyestalk Ablation 3Maturation & Spawning
Crustacea
Eyestalk ablation is a method where half to two thirds of the
eyestalk of shrimp is removed (Antony and Kumar, 2022)
Pinching, this is a simple technique where half to two third
down the eyestalk is removed or pinched off. It leaves an
open wound hence, would create stress to the animal.
Slitting, here one eye is cut with a razor blade and then
crushing the eyestalk, with thumb and index fingernail
(enucleation), moving distally, half to two-third down the
eyestalk, till the entire content of the eye is removed. The
advantage here is that it leaves behind a transparent
exoskeleton; hemolymph clotting and closure of the wound
occur quickly.
Cauterizing, it can be done either using an electro cautery
device or instruments like red-hot wire or forceps to remove
the eyestalk. Here the wound is closed completely and scar
tissue is formed more rapidly when performed correctly.
Ligation, the eyestalk is tied tightly around the base, as
close as possible to the carapace; with a surgical thread or
any other thread. This prevents the flow of hormones. This
leads to falling off of eyestalks within a few days.
Unilateral (removal of one eyestalk) or
Bilateral (removal of both eyestalks)
Unilateral ablation is widely practiced
The Technique of Eyestalk Ablation
Cutting, this technique common used where the eyestalk is
removed by scissors.
Bilateral ablation as the latter has greater
demerits such as higher mortality rate,
reabsorption of eggs without spawning etc.
Eyestalk Ablation Advantages 1/4 3Maturation & Spawning
Crustacea
Larvae survival of spawns ablated and unablated
P. vannamei
females
Percent of unablated (n= 60) and ablated (n= 37) white Pacific
shrimp,
P. vannamei
, females that never spawned, or that spawned
once, twice, etc. during the production period (3 months)
Ovary biochemical variables between ablated (n=12) and unablated (n=15) white Pacific
shrimp,
P. vannamei
, as a function of the stage of gonadal maturation (immature or ripe).
Ablated females had more frequent spawns and a higher
gonadosomatic index (Palacious
et al
., 1999)
Eyestalk Ablation Advantages 2/4 3Maturation & Spawning
Crustacea
Diagram of the eyestalk ablation experiment (A) and physiology of
shrimp and ovary (B) (Umaporn et al., 2011).
GSI values, a known indicator of ovarian maturation in the female
black tiger shrimp
The physiological changes and colors of ovaries indicated rapid
maturation after the eyestalk ablation
The unilateral eyestalk ablation evidently induced ovarian
maturation within seven days.
Eyestalk Ablation Advantages 3/4 3Maturation & Spawning
Crustacea
Unilateral eyestalk ablation is
promising for the cultivation
of
Spiralothelphusa
hydrodroma
UEA in
S. hydrodroma
sufficiently induced gonadal
and growth development
(Rebecca and Dhivya, 2019)
Reproductive indices in S. hydrodroma
Growth and survival indices in
S. hydrodroma
Eyestalk Ablation Advantages 4/4 3Maturation & Spawning
Crustacea
Effect of unilateral and bilateral eyestalk
ablation of circulating hemolymph MF
levels in female Libinia emarginata
Correlation of MF concentrations with
ovarian development in control (non-
ablated) female
L. emarginata
(0.45 ng/ml)
Correlation of MF concentrations with ovarian
development in unilaterally eyestalk ablated female
L. Emarginata
(6 -fold, 1.78ng/ml)
Correlation of MF concentrations with ovarian
development in bilaterally eyestalk ablated female
L. emarginata
(10-fold, 3.28ng/ml)
MF at certain concentrations may trigger
ovarian development, over-production of MF,
caused by eyestalk ablation, may possibly
contribute towards this formation of lower
quality eggs (Jo
et al
., 1999)
Eyestalk ablation increased MF concentrations
in the hemolymph and a stimulation of ovarian
development evidenced by increased GSIs,
commenced earlier than that of control
The removal of both eyestalks by bilateral
ablation would presumably totally remove all
sources of inhibitory neuropeptides including GIH
and MO-IHs, thereby allowing for uncontrolled
stimulation of reproduction and MF synthesis
Negative Impacts of Eyestalk
Ablation 1/2 3Maturation & Spawning
Crustacea
Reproductive performance and morphometric parameters
of females of
Farfantepenaeus brasiliensis
broodstock
The decrease of the
gonad-inhibiting hormone
causing ovarian growth
Females had stored
reserves of proteins and
lipids to be transported to
the ovaries
The oocytes of ablated
L.
vannamei
females develop
abruptly, causing
malformations or a
reduction in the transfer of
some energy-rich
biomolecules to the eggs
(Magana-Gallegos et al.,
2018)
Gonadosomatic (A) and hepatosomatic (B) indexes of
females of
Farfantepenaeus brasiliensis
broodstock
with unilateral eyestalk ablation and non-ablated
eyestalks in a 45-day experimental period
Negative Impacts of Eyestalk
Ablation 2/2 3Maturation & Spawning
Crustacea
Effect of eyestalk ablation (EA) on the
duration of the molt cycle in
Litopenaeus vannamei
. (C) control
shrimps, (U) unilaterally ablated and (B)
bilaterally ablated females and males.
Mortality probably caused by
impairment of several
physiological functions
mediated by hormones from
the eyestalk and direct injury
of the nervous system.
Produces severe trauma,
destroys a mayor portion of
the nervous system, and
renders the animal blind.
The lower concentration of molt-
inhibiting hormone caused by
ablation
The capacity of immune response inferred from proPO
content and PO activity decreased only in bilaterally
ablated shrimp, suggesting higher susceptibility to
pathogens.
Effect of eyestalk ablation (EA) on hemolymph prophenoloxidase
content (a) and phenoloxidase activity (b) in
Litopenaeus
vannamei
. (C) Control shrimp, (U) unilaterally ablated and (B)
bilaterally ablated females and males.
Effect of eyestalk ablation (EA) on mortality
2%
35%
68%
0
10
20
30
40
50
60
70
80
Control shrimp Unilaterally
ablated Bilaterally
ablated
Mortality (%)
Eyestalk Ablation vs Fish Welfare 3Maturation & Spawning
Crustacea
Alternatives to Eyestalk Ablation 3Maturation & Spawning
Crustacea
Hormonal administration like serotonin (5HT), methyl
farnesoate (MF) and several isoforms of gonadotropin-
releasing hormones (GnRHs) developed ovarian maturation
and spawning rate at a level comparable to that of unilateral
eyestalk ablated shrimp (Antony and Kumar, 2022)
Schematic representation of the ten reproduction-related
research subjects identified as potential improving fields
for the shrimp industry (Alfaro et al., 2019)
While the ablation can induce ovarian maturation, it also
jeopardizes growth, shortens molting cycle, increases
energetic demands, and resulting in an eventual loss in egg
quality and high mortality (Uawisetwathana et al., 2011).
RNA interference (RNAi) is a cellular natural defense against
intruding RNAs such as viruses or transposon. It is a post-
transcriptional gene silencing phenomenon by which long
double-stranded RNA (dsRNA) triggers the silencing of the
target gene in a sequence-specific manner. RNAi using dsRNA
molecules to silence GIH transcripts has been considered as
an alternative technique to eyestalk ablation on
P. monodon
and
L. vannamei
(Alfaro et al., 2019)
Alternatives to Eyestalk Ablation 1/7
Serotonin Hormone 3Maturation & Spawning
Crustacea
Injection of 5HT at 50 μg/g BW is capable of
inducing ovarian maturation and spawning in
female
P. monodon
broodstock, similar to
the induction by eyestalk ablation.
Weekly spawning rate of
P. vannamei
treated by different protocols, b.w.: body weight.
Spawnings obtained by serotonin
treatment showed excellent quality,
and it was not statistically different
from unilaterally eyestalk ablated
females (Vaca and Alfaro, 2000)
Alternatives to Eyestalk Ablation 2/7
Gonadotropin-releasing hormones (GnRH) 3Maturation & Spawning
Crustacea
Effects of GnRHs and DA on the ovarian maturation period in
L. vannamei
Gonadotropin-releasing hormones (GnRH) is a
neuropeptide hormone that regulates reproductive,
the GnRH at a dose of 25 ng/g BW was effective and
could be used in aquaculture practice
The ability of these GnRH isoforms in binding and the
receptor binding may be imparted by the amino acids
(Tinikul
et al
., 2014)
Dopamine (DA) hormone has been thought to have
an inhibitory effect on gonadal maturation by
stimulating the release of gonad-inhibiting
hormone (GIH), and/or by inhibiting the release of a
putative gonad-stimulating hormone (GSH)
Alternatives to Eyestalk Ablation 3/7
Serotonin & GnRH Hormone 3Maturation & Spawning
Crustacea
Androgenic gland (AG), which
controls testicular maturation
and male sex development in
decapods, via insulin-like
androgenic gland hormone (IAG),
due in part to the increased
proliferation of AG cells
Androgenic gland-somatic index (ASI) value for each group at day 12 and 16
5-HT and l-GnRH-III through
significant increases in AG size,
proliferation of AG cells, and
Mr
-
IAG production
DA and Crz caused inhibitory
effects on the AG through
significant decreases in AG
size, proliferation of AG cells,
and
Mr
-IAG production
5-HT and certain GnRHs can be
now used to stimulate reproduction
in male
M. rosenbergii
Alternatives to Eyestalk Ablation 4/7
Methyl Farnesoate Hormone 3Maturation & Spawning
Crustacea
The
in vivo
assay showed a positive
effect of MF on oocyte growth when
injected alone and in combination
with 17β-estradiol, but not in
combination with JHIII or 17α-
hydroxyprogesterone
Gonadosomatic indexes at the end of the in vivo
assay.
Uptake of labeled leucine by oocytes at
the end of the first in vitro assay.
17α-hydroxyprogesterone completely
suppressed the stimulatory action of
the MO on the ovary
Alternatives to Eyestalk Ablation 5/7
Methyl Farnesoate Hormone 3Maturation & Spawning
Crustacea
JH injections at 109 ng g-1 caused some negative
effect on sperm count after successive
ejaculations
MF at a similar dose (120 ng g-1) apparently
induced a positively significant response in
sperm counts and sperm abnormalities
Variance among replicates was low and the
effect of MF was so strong that a clear and
significant difference was detected regardless of
small sample size; however, this statement
requires further experimental confirmation using
more replicates.
Evaluation of sperm counts and sperm
abnormalities after successive
spermatophore ejaculations for
Litopenaeus vannamei
injected with five
doses of JH III (109 ng g-1 b.w.) or vehicle
solution (control group).
Evaluation of sperm counts and sperm
abnormalities after a single ejaculation
for
Litopenaeus vannamei
injected with
five weekly doses of MF (120 or 1200 ng
g-1 b.w.) or vehicle solution (control
group). Baseline values were included
as a reference.
Alternatives to Eyestalk Ablation 6/7
17α-OHP & 17α-OHPL Hormone 3Maturation & Spawning
Crustacea
Steroid-based hormones i.e. 17α-
hydroxyprogesterone (17α-OHP) and
17α-hydroxypregnenolone (17α-OHPL)
injection recognized as gonad
stimulating hormones
Gonad Somatic Index (GSI) for crabs
S. olivacea
from
the control and treatment groups (17α-OHP at 0.01
μg/g BW (T1D1) and 0.1 μg/g BW(T1D2)).
Gonad Somatic Index (GSI) for crabs
S. olivacea
from the control and treatment groups
(17α-OHPL at 0.01 μg/g BW (T2D1) and 0.1 μg/g
BW (T2D2))
Mean oocyte diameter (μm) of
S. olivacea
from
the control, T1D1 and T1D2 treatments groups of
17α-OHP from days 0 to 60.
Mean oocyte diameter (μm) of
S. olivacea
from the
control, T2D1 and T2D2 treatments groups of
17α-OHPL from Days 0 to 60.
0.01 μg/g BW of 17α-OHPL was the
most suitable hormone at optimum
concentration to stimulate
S. olivacea
ovarian maturation and produce the
highest GSI as well as large oocytes
Alternatives to Eyestalk Ablation 7/7
Thyroxine Hormone 3Maturation & Spawning
Crustacea
The supplementation of thyroxine hormone with
low dose (0.05µg/ BW) was effective to increase
ovarian maturation of female mud crab (
Scylla
serrata
) than control (Iromo
et al
., 2014)
Thyroxine is a hormone to stimulate the
growth and development of the gonads
The supplementation of thyroxine hormone low
dose can increase the survival of female maturity
than control. Hormone thyroxine in excessive
have disturb the function of organs body
The supplementation of thyroxine hormone
have been improved the quality of female and
larvae
RNA Interference Technology 1/3 3Maturation & Spawning
Crustacea
The potential of RNAi technology for silencing
hormonal transcripts in domesticated
L. vannamei
in
order to achieve gonadal development
RNAi-based technique to stimulate gonadal
development and spawning in
L. vannamei
, alternative
to the traditional method of eyestalk ablation
Mean oocyte diameters observed in
L. vannamei
females
Levels of GIH and vitellogenin transcripts detected in
eyestalk and ovaries (Feijo
et al
., 2016)
I control group, intramuscular injection of 150 μl saline solution, group II
intramuscular injection of 2.8 μg/g of dsRNA-GIH, group III
intramuscular injection of 2.8 μg/g of dsRNA-IGSF4D, group IV unilateral
eyestalk-ablation.
RNA Interference Technology 2/3 3Maturation & Spawning
Crustacea
dsRNA of GIH was demonstrated to be able to knockdown GIH
expression and induce ovarian maturation in
P. monodon
Shrimp injected with GIH dsRNA at the concentration of 0.3μg/g bw of
shrimp showed a significant decrease(68%) in GIH transcript level when
compared to the control shrimp
Feeding of shrimp with 0.3g of wet weight of GIH dsRNA-enriched Artemia,
4 times per days resulted in a smaller (28%) but still significant decrease
in GIH transcript level when compared to the controls
Silencing of GIH expression in the opticlobes of
P.monodon
fed with GIH dsRNA-enriched Artemia
(Treerattrakool
et al
., 2013)
Oral delivery of dsRNA is more
convenient, suitable and cost effective
for commercial applications because
not require individual manipulation
and thus can be applied easily without
causing stress to the shrimp
Feeding
P. monodon
with GIHds RNA-enriched Artemia was able to confer
partial suppression of GIH gene expression in the shrimp
RNA Interference Technology 3/3 3Maturation & Spawning
Crustacea
A single injection of GIH-dsRNA into
previtellogenic female
P. monodon
at the
concentration of 3 µg GIH dsRNA per gram body
weight was able to inhibit GIH expression for a
minimum of 30 days
Ovarian maturation and spawning in domesticated (a) and wild (b)
female
P. monodon
after injection of dsRNA
Spawning of wild broodstocks (Treerattrakool
et al
., 2011)
RNAi could stimulate gonadal development
and spawning in wild
P. monodon.
SUMMARY 4Summary
Hormone treatment is one of
the reproduction control
strategies including maturation
and spawning of shellfish and
crustacea breeding towards
sustainable aquaculture
Maturation and spawning
of shellfish can be
controlled by using
hormone treatment such
as serotonin (5 HT- ), sex
steroids (testosterone and
estradiol), estrogen
hormone (estradiol-17β),
and gonadotropin-
releasing hormone (GnRH)
Eyestalk ablation could be
improving the maturation and
spawning of crustacea, however, it
has side effects i.e high mortality
Serotonin, gonadotropin-releasing
hormone (GnRH), Methyl farnesoate
(MF), Steroids hormone (17α-
hydroxyprogesterone (17α-OHP) and
17α-hydroxypregnenolone (17α-OHPL),
and thyroxine hormone can be used for
controlling the maturation and spawning
of crustacea
Hormone treatment and RNA interface
technology can be used as an alternative
of eyestalk ablation for improving the
maturation and spawning of crustacea.
Aulia Deni
Aquafeed Nutrition Laboratory
Department of Fisheries Biology
Collage of Fisheries Science
Pukyong National University
damursalin@gmail.com / auliadeni@pukyong.ac.kr
Presentation References
REFERENCES
1. Alfaro, J., Zúñiga, G., García, A., & Rojas, E. (2008). Preliminary evaluation of the effect of juvenile hormone III and methyl farnesoate on spermatophore quality
of the white shrimp,
Litopenaeus vannamei
Boone, 1931 (Decapoda: Penaeidae).
Revista de biología marina y oceanografía
,
43
(1), 167-171.
2. Alfaro-Montoya, J., Braga, A., & Umaña-Castro, R. (2019). Research frontiers in penaeid shrimp reproduction: Future trends to improve commercial
production.
Aquaculture
,
503
,70-87.https://doi.org/10.1016/j.aquaculture.2018.12.068
3. Anne Rebecca, A., & Dhivya, K. (2019). Unilateral eyestalk ablation induced gonadal maturation in
Spiralothelphusa hydrodrom
.
Journal of Emerging
Technologies and Innovative Research
,
6
(5), 535-551.
4. Antony, A. and Kumar, P. 2022. Eyestalk Ablation Technique in Shrimp Hatcheries: Its Negative Impacts and Possible Alternatives. Vigyan Varta 3(2): 9-12.
5. Apine, E., Ramappa, P., Bhatta, R., Turner, L. M., & Rodwell, L. D. (2023). Challenges and opportunities in achieving sustainable mud crab aquaculture in
tropical coastal regions.
Ocean & Coastal Management
,
242
, 106711. https://doi.org/10.1016/j.ocecoaman.2023.106711
6. Avdelas, L., AvdicMravlje, E., Borges Marques, A. C., Cano, S., Capelle, J. J., Carvalho, N., ... & Asche, F. (2021). The decline of mussel aquaculture in the
European Union: Causes, economic impacts and opportunities.
Reviews in Aquaculture
,
13
(1), 91-118.doi: 10.1111/raq.12465
7. Azra MN, Okomoda VT and Ikhwanuddin M (2022) Breeding Technology as a Tool for Sustainable Aquaculture Production and Ecosystem Services. Front. Mar.
Sci. 9:679529. doi: 10.3389/fmars.2022.679529
8. Bach, L., Sonne, C., Rigét, F. F., Dietz, R., & Asmund, G. (2014). A simple method to reduce the risk of cadmium exposure from consumption of Iceland scallops
(
Chlamys islandica
) fished in Greenland.
Environment international
,
69
, 100-103. http://dx.doi.org/10.1016/j.envint.2014.04.008
9. Becker, C., & Bauer, R. T. (2020). Multiple matings and sperm competition.
The natural history of crustacea
,
6
,332-363.
DOI:10.1093/oso/9780190688554.003.0012
10. Burnside, W. M. (2010). The influence of two estrogens on the sex and ovarian development of eastern oysters (
Crassostrea virginica
) maintained in a closed
recirculating system. Louisiana State University and Agricultural & Mechanical College.
REFERENCES
11. Chan, S., Wang, W., Shi, L., Liu, J., Zhou, T., Wang, C., & Amankwah, B. K. (2019). Eyestalk ablation, a prerequisite for Crustacean reproduction: a review.
Israeli
Journal of Aquaculture-Bamidgeh
,
71
.
12. Creswell, R. L., Ohs, C. L., Kasper, C. S., Martinez, C. V., Livengood, E. J., Garr, A. L., ... & Myers, B. E. (2010). Teach Aquaculture Curriculum: Spawning and
Rearing Bivalve Molluscs--Larval Culture: FA175/FA175, 7/2010.
EDIS
,
2010
(5). http://edis.ifas.ufl.edu/FA177.
13. Dineshbabu, A.P, Geetha Sasikumar, Prathibha Rohit, Sujitha Thomas, K.M. Rajesh and P.U. Zacharia, 2014. Methodologies for studying finfish and shellfish
biology, CMFRI-NICRA publication No.2, Central Marine Fisheries Research Institute, Kochi. 91 p
14. Duarte-Restrepo, E., Jaramillo-Colorado, B. E., & Duarte-Jaramillo, L. (2020). Effects of chlorpyrifos on the crustacean
Litopenaeus vannamei
.
PloS one
,
15
(4),
e0231310. https://doi. org/10.1371/journal.pone.0231310
15. E. Palacios, D. Carreno, M. C. Rodríguez-Jaramillo & I. S. Racotta (1999) Effect of Eyestalk Ablation on Maturation, Larval Performance, and Biochemistry of
White Pacific Shrimp,
Penaeus vannamei
, Broodstock, Journal of Applied Aquaculture, 9:3, 1-23,DOI:10.1300/J028v09n03_01
16. FAO. 2022. The State of World Fisheries and Aquaculture 2022. Towards Blue Transformation. Rome, FAO. https://doi.org/10.4060/cc0461en
17. Feijó, R. G., Braga, A. L., Lanes, C. F., Figueiredo, M. A., Romano, L. A., Klosterhoff, M. C., ... & Marins, L. F. (2016). Silencing of gonad-inhibiting hormone
transcripts in
Litopenaeus vannamei
females by use of the RNA interference technology.
Marine Biotechnology
,
18
,117-123. DOI 10.1007/s10126-015-9676-2
18. Frederick, A. R., Lee, A. M., Wehrle, B. A., Catabay, C. C., Rankins, D. R., Clements, K. D., & German, D. P. (2022). Abalone under moderate heat stress have
elevated metabolic rates and changes to digestive enzyme activities.
Comparative Biochemistry and Physiology Part A: Molecular & Integrative
Physiology
,
270
, 111230. https://doi.org/10.1016/j.cbpa.2022.111230
19. Gambill, J. M., Doyle, A. E., Lee, R. F., Geer, P. J., Walker, A. N., Parker, L. G., & Frischer, M. E. (2015). The mystery of Black Gill: shrimpers in the South Atlantic
face off with a cryptic parasite.
Current: The Journal of Marine Education
,
29
(4), 2-8.
20. Hau, C., & Haryana, H. Shrimp Culture (
Litopenaeus vannamei
) And Its Management.
Dr. Mamta Shukla
,62.
REFERENCES
21. Hidir, A., AaqillahAmr, M. A., Azra, M. N., Shahreza, M. S., Abualreesh, M. H., Peng, T. H., ... & Ikhwanuddin, M. (2021). Sexual dimorphism of mud crab, genus
Scylla between sexes based on morphological and physiological characteristics.
Aquaculture Research
,
52
(12), 5943-5961. DOI:10.1111/are.15497
22. Iromo, H., Junior, M. Z., & Manalu, W. (2014). Effectivy of thyroxine hormone suplementation in the ovarian maturation of females mud crab (
Scylla
serrata
).
Pakistan Journal of Biotechnology
,
11
(2), 79-86.
23. Jardillier, E., Rousseau, M., Gendron-Badou, A., Fröhlich, F., Smith, D. C., Martin, M., ... & Auzoux-Bordenave, S. (2008). A morphological and structural study of
the larval shell from the abalone
Haliotis tuberculata
.
Marine Biology
,
154
, 735-744. DOI 10.1007/s00227-008-0966-3
24. Jin S, Bian C, Ma J, Wang P, Xu P and Fu H (2022) Editorial: Sex Determination and Developmental Mechanism of Crustacean and Shellfish. Front. Endocrinol.
13:940144. doi: 10.3389/fendo.2022.940144
25. Jo, Q. T., Laufer, H., Biggers, W. J., & Kang, H. S. (1999). Methyl farnesoate induced ovarian maturation in the spider crab,
Libinia emarginata
.
Invertebrate
reproduction & development
,
36
(1-3), 79-85.
26. Lodeiros, C., Valentich-Scott, P., Chávez-Villalba, J., Mazón-Suástegui, J. M., & Grijalva-Chon, J. M. (2020). Tropical and subtropical Ostreidae of the American
Pacific: taxonomy, biology, ecology, and genetics.
Journal of Shellfish Research
,
39
(2), 181-206. DOI:10.2983/035.039.0202
27. Magaña-Gallegos, E., Bautista-Bautista, M., González-Zuñiga, L. M., Arevalo, M., Cuzon, G., & Gaxiola, G. (2018). Does unilateral eyestalk ablation affect the
quality of the larvae of the pink shrimp
Farfantepenaeus brasiliensis
(Letreille, 1817)(Decapoda: Dendrobranchiata: Penaeidae)?.
Journal of Crustacean
Biology
,
38
(4), 401-406. doi:10.1093/jcbiol/ruy043
28. Martinez, J. D. (2020). Effects of Copper and Temperature on the Life Stages of the Invasive Zebra Mussel (Doctoral dissertation, Texas Christian University).
29. Muhd-Farouk, H., Jasmani, S., & Ikhwanuddin, M. (2016). Effect of vertebrate steroid hormones on the ovarian maturation stages of orange mud crab,
Scylla
olivacea
(Herbst, 1796).
Aquaculture
,
451
,78-86.http://dx.doi.org/10.1016/j.aquaculture.2015.08.038
30. Nagaraju, G. P. C. (2011). Reproductive regulators in decapod crustaceans: an overview.
Journal of Experimental Biology
,
214
(1), 3-16.doi:10.1242/jeb.047183
REFERENCES
31. Nagasawa K, Oouchi H, Itoh N, Takahashi KG, Osada M (2015) In Vivo Administration of Scallop GnRH-Like Peptide Influences on Gonad Development in the
Yesso Scallop,
Patinopecten yessoensis
. PLoS ONE 10(6): e0129571. doi:10.1371/journal.pone.0129571
32. Nowland, S. J., O’Connor, W. A., Elizur, A., & Southgate, P. C. (2021). Evaluating spawning induction methods for the tropical black-lip rock oyster,
Saccostrea
echinata
.
Aquaculture Reports
,
20
, 100676. https://doi.org/10.1016/j.aqrep.2021.100676
33. Nuurai, P., Wanichanon, C., & Wanichanon, R. (2020). Effect of gonadotropin releasing hormone on the expression of luteinizing hormone and estrogen in the
nerve ganglia and ovary of a tropical abalone,
Haliotis asinina
Linnaeus.
Acta Histochemica
,
122
(1), 151454. https://doi.org/10.1016/j.acthis.2019.151454
34. Pamuru, R. R. (2019). Endocrinology of reproduction in crustaceans. In
Comparative Endocrinology of Animals
. IntechOpen.
35. Quinitio, E. T., & Parado-Estepa, F. D. (2008). Biology and hatchery of mud crabs
Scylla spp
. Aquaculture Department, Southeast Asian Fisheries Development
Center.
36. Rodríguez, E. M., Greco, L. S. L., Medesani, D. A., Laufer, H., & Fingerman, M. (2002). Effect of methyl farnesoate, alone and in combination with other
hormones, on ovarian growth of the red swamp crayfish,
Procambarus clarkii
, during vitellogenesis.
General and comparative endocrinology
,
125
(1), 34-40.
doi:10.1006/gcen.2001.7724
37. Sainz-Hernández, J. C., Racotta, I. S., Dumas, S., & Hernández-López, J. (2008). Effect of unilateral and bilateral eyestalk ablation in
Litopenaeus vannamei
male and female on several metabolic and immunologic variables.
Aquaculture
,
283
(1-4), 188-193. http://dx.doi.org/10.1016/j.aquaculture.2008.07.002
38. Schwaebe, L., Acharya, K., & Nicholl, M. J. (2013). Comparative efficacy of
Dreissena rostriformis bugensis
(Bivalvia: Dreissenidae) spawning
techniques.
Aquatic Invasions
,
8
(1). doi: http://dx.doi.org/10.3391/ai.2013.8.1.05
39. Shampa SA, N Nasrin, M Khatun and S Akter, 2017. Species availability, culture technique, reproduction of prawn and shrimp in Bangladesh: A review. Res.
Agric. Livest., Fish., 4 (2): 107-116.
REFERENCES
40. Siangcham, T., Tinikul, Y., Poljaroen, J., Sroyraya, M., Changklungmoa, N., Phoungpetchara, I., ... & Sobhon, P. (2013). The effects of serotonin, dopamine,
gonadotropin-releasing hormones, and corazonin, on the androgenic gland of the giant freshwater prawn,
Macrobrachium rosenbergii
.
General and
comparative endocrinology
,
193
,10-18. Inc. http://dx.doi.org/10.1016/j.ygcen.2013.06.028
41. Tinikul, Y., Poljaroen, J., Tinikul, R., Anuracpreeda, P., Chotwiwatthanakun, C., Senin, N., ... & Sobhon, P. (2014). Effects of gonadotropin-releasing hormones and
dopamine on ovarian maturation in the Pacific white shrimp,
Litopenaeus vannamei
, and their presence in the ovary during ovarian
development.
Aquaculture
,
420
,79-88.http://dx.doi.org/10.1016/j.aquaculture.2013.10.036
42. Treerattrakool, S., Panyim, S., & Udomkit, A. (2011). Induction of ovarian maturation and spawning in
Penaeus monodon
broodstock by double-stranded
RNA.
Marine biotechnology
,
13
,163-169.DOI 10.1007/s10126-010-9276-0
43. Treerattrakool, S., Chartthai, C., Phromma-in, N., Panyim, S., & Udomkit, A. (2013). Silencing of gonad-inhibiting hormone gene expression in
Penaeus
monodon
by feeding with GIH dsRNA-enriched Artemia.
Aquaculture
,
404
,116-121. http://dx.doi.org/10.1016/j.aquaculture.2013.04.024
44. Tweedley, J. R., Campbell, T. I., Loneragan, N. R., & Johnstone, D. (2017). Aspects of the biology and husbandry of portunid crabs relevant to aquaculture-based
enhancement and fisheries management. Murdoch University. https://researchportal.murdoch.edu.au/esploro/outputs/report/Aspects-of-the-biology-and-
husbandry /991005540333107891
45. Uawisetwathana U, Leelatanawit R, Klanchui A, Prommoon J, Klinbunga S, et al. (2011) Insights into Eyestalk Ablation Mechanism to Induce Ovarian Maturation
in the Black Tiger Shrimp. PLoS ONE 6(9): e24427. doi:10.1371/journal.pone.0024427
46. United Nations Department of Economic and Social Affairs, Population Division (2022). World Population Prospects 2022: Summary of Results. UN
DESA/POP/2022/TR/NO. 3.
47. Vaca, A. A., & Alfaro, J. (2000). Ovarian maturation and spawning in the white shrimp,
Penaeus vannamei
,by serotonin injection.
Aquaculture
,
182
(3-4), 373-
385.
48. Wallace, R. K., Waters, P., & Rikard, F. S. (2008). Oyster hatchery techniques (No. 4302). Stoneville, MS: Southern Regional Aquaculture Center.
REFERENCES
49. Wang, C., & Croll, R. P. (2006). Effects of sex steroids on spawning in the sea scallop,
Placopecten magellanicus
.
Aquaculture
,
256
(1-4), 423-432.
doi:10.1016/j.aquaculture.2006.01.017
50. Wilder, M. N. (2019). Advances in the science of crustacean reproductive physiology and potential applications to new seed production technology.
Journal of
Coastal Research
,
86
(SI), 6-10.DOI:10.2112/ SI86-002.1
51. Wongprasert, K., Asuvapongpatana, S., Poltana, P., Tiensuwan, M., & Withyachumnarnkul, B. (2006). Serotonin stimulates ovarian maturation and spawning in
the black tiger shrimp
Penaeus monodon. Aquaculture
,
261
(4), 1447-1454. doi:10.1016/j.aquaculture.2006.08.044
52. Yap, C. K., Ng, Y. J. E., Thomas, F. B. E., Cheng, W. H., & Ong, G. H. (2016). The Use of Foot of the Green-Lipped Mussel is
Perna viridis
as an Alternative Method
to Reduce the Gender Effect on the Bioaccumulation of Cu and Zn in the Mussel.
Annals of Limnology and Oceanography
,
1
(1), 022-025.
53. Zamri, A. S., Zulperi, Z., Esa, Y., & Syukri, F. (2022). Hormone Application for Artificial Breeding Towards Sustainable AquacultureA Review.
Pertanika Journal
of Tropical Agricultural Science
,
45
(4). DOI:https://doi.org/10.47836/pjtas.45.4.11
ResearchGate has not been able to resolve any citations for this publication.
Article
Full-text available
Aquaculture plays a significant role in food security and provides livelihoods and employment for millions of people among coastal communities worldwide. However, the growing aquaculture sector has also created debates around its long-term ecological sustainability, economic viability, potential social inequalities and governance issues. We investigated the perceived challenges and opportunities to achieving sustainable mud crab aquaculture in tropical coastal regions by using the case study of coastal mud crab farms in Andhra Pradesh, India. Informed by perceptions and indicative financial data from a sample of stakeholders we investigated the potential economic outcomes under different scenarios representing varying yield levels, risk factors and project time periods. The main risks identified by the stakeholders were associated with the limited supply of mud crab seeds and the lack of access to governmental and non-governmental support schemes. There are no financial buffers, therefore major disease outbreaks or extreme weather conditions caused by climate change would lead to a loss of livelihoods. This paper also highlights the most critical factor determining the level of success of mud crab farming being the crab survival rate which is influenced by a variety of factors including increasing sea surface temperature. The results of this study show that small-scale mud crab farming has fewer risks and higher flexibility involved than large-scale mud crab farming. It could be an economically sustainable enterprise and serve as a tool for poverty alleviation in developing countries if microfinance support and training are available.
Article
Full-text available
Aquaculture is the aquatic equivalent of agriculture. While agriculture is predominantly based on the use of freshwater to grow crops, aquaculture utilizes freshwater (i.e. inland waters) and brackish water/seawater (i.e. coastal waters) to culture fish, plants, shellfish (bivalve, abalone, sea urchins and sea cucumbers), macro and microalgae. The increasing scarcity of captive aquatic fisheries resources has led to the regenerative farming practices of aquaculture. Aquaculture is the fastest-growing food sector in the world and about the most important means of providing sustainable food production currently. Among the several aquaculture techniques used, breeding technology has been exploited to improve food production. Beyond captive production, breeding technology has also been exploited for restocking programs of many aquatic ecosystems (i.e. rivers, lakes, sea, estuaries, etc.), hence, contributing positively to their management and ecosystem services. This comment, therefore, highlights some breeding technology as regards to their ability to improve sustainable captive production and aquatic ecosystem services.
Article
Full-text available
When developing a species-specific hatchery protocol it is important to investigate the triggers for spawning, which is the foundation of the production cycle. This study evaluated multiple spawning induction techniques to optimise the spawning success of black-lip rock oyster, Saccostrea echinata, broodstock. Initially, the most effective method for non-destructively opening broodstock was determined, to allow intramuscular injection of chemical stimuli. Following this, the efficacy of seven spawning induction treatments, including two physical shock techniques, three chemical induction techniques, a combination of physical and chemical induction and strip spawning were assessed. Based on the outcomes of these trials, the combined and independent effects of reduced salinity and addition of sperm, as well as the potential of neuropeptides to trigger spawning, were evaluated. Results demonstrated that a concentration of 30 g/L of MgCl2 is an effective muscle relaxant for commercial and research application for S. echinata. It was determined that salinity reduction, rather than temperature increase, is a key factor for spawning induction. Strip spawning is a viable option for S. echinata; however, sperm motility was significantly affected, and fecundity and fertilisation rates were lower (although not significant, P > 0.05) when compared to other induction methods tested. A combination of physical and chemical induction, involving reduced salinity and addition of sperm, was the most successful treatment; 80 % of broodstock spawned within 19 min of salinity drop and addition of sperm. This method delivers significant production improvements for S. echinata, particularly regarding the time taken to induce spawning, and is therefore recommended for application in the hatchery.
Chapter
Full-text available
This is the sixth volume of a ten-volume series on The Natural History of the Crustacea. The volume synthesizes in nineteen chapters our current understanding of diverse topics in crustacean reproductive biology. The first part of the volume address allocation strategies to reproduction, gamete production, brooding behavior and other components of parental care in crustaceans. The second part of the volume centers on sexual systems in crustaceans. The third section of the volume covers crustacean mating systems and sexual selection. The volume ends with three chapters covering diverse topics including reproductive rhythms, and crustacean personality research, and record breaking crustaceans with respect to reproductive characters. Collectively, these nineteen chapters provide an integrative and comprehensive treatment of crustacean reproductive biology from gamete formation to mating and reproductive strategies and their evolutionary and ecological consequences.
Article
Full-text available
Oysters have throughout history been one of the most important marine invertebrate animals used, whether as human food or as a cultural base. Today, they represent one of the most exploited natural resources, are produced by aquaculture activities, and are one of the most studied groups of shellfish. This is most evident in temperate zones, whereas studies in tropical zones have been comparatively scarce and somewhat disorganized. The present review organizes the studies of a dozen species that are grouped as oysters of the tropical and subtropical American Pacific, considering their taxonomy and identification, as well as their distribution, and establishing an identification key using the characteristics of the shell. Aspects of their biology are described, referring to general anatomy with a type species, the Cortez oyster Crassostrea corteziensis, as well as the life cycle, taking as reference the recent studies carried out on the rock oyster Striostrea prismatica. In the same way, a description of their populations and ecological interactions is provided, emphasizing the reproduction of the different species and ordering the description of the main stages in the gametogenic development of the populations in a latitudinal form. The main diseases and some uses of oysters as bioaccumulating organisms are also described, as well as phylogenetic and population genetic studies. Finally, possible future actions are discussed to provide a more comprehensive knowledge of oysters from the tropics and subtropics of the American Pacific based on the conservation and use of the resources.
Article
Aquaculture has been the fastest-growing area of worldwide food production and is becoming a vital component of the global economy to feed the rising world population. Hence, directed toward continuing the current level of per head consumption, comprehensive aquaculture production needs to attain eighty million tonnes by 2050. However, some cultured marine fish species, such as salmonids, striped bass, and gilthead seabream, as well as freshwater fish, such as captive Mediterranean amberjack populations (Seriola dumerili) and Mekong River giant catfish (Pangasianodon gigas), exhibit reproductive dysfunction, especially in female brood stock when reared in captivity. Captive females face complications with unsynchronised ovulation, fail to undergo final oocyte maturation (FOM), and no longer spawn due to a lack of luteinising hormone (LH). Thus, artificial breeding has been widely used in aquaculture practices to increase cultured fish production. Farmer has extensively applied commercial hormones such as human chorionic gonadotropin (hCG), Ovaprim, Ovatide, and Ovaplant, through injection and implantation of hormones to stimulate breeding in many farmed fish species. However, artificial breeding is still in its development phase, and some methods are still unable to induce spawning in certain fish species. Different methods, doses, and delivery systems of artificial hormones could improve the efficiency and effectiveness of artificial breeding. This paper discusses the current research on artificial breeding in various fish species as well as new approaches or techniques to be applied in the area to regulate the reproductive process in captive fish for sustainable aquaculture.
Article
Abalone around the world are subject to increasing frequency of marine heatwaves, yet we have a limited understanding of how acute high temperature events impact the physiology of these commercially and ecologically important species. This study examines the impact of a 5 °C temperature increase over ambient conditions for six weeks on the metabolic rates, digestive enzyme activities in the digestive gland, and digestive efficiency of Red Abalone (Haliotis rufescens) and Pāua (H. iris) on their natural diets. We test the hypothesis that abalone digestive function can keep pace with this increased metabolic demand in two separate experiments, one for each species. H. iris had higher food intake in the heat treatment. Both species had higher metabolic rates in the heat treatment with Q10 = 1.73 and Q10 = 2.46 for H. rufescens and H. iris, respectively. Apparent organic matter digestibility, protein digestibility, and carbohydrate digestibility did not differ between the heat treatment and the ambient (control) treatment in either experiment. H. rufescens exhibited higher maltase, alanine-aminopeptidase, and leucine-aminopeptidase activities in the heat treatment. Amylase, β-glucosidase, trypsin, and alkaline phosphatase activities in the digestive gland tissue did not differ between temperature treatments. H. iris exhibited lower amylase and β-glucosidase activities in the heat treatment, while maltase, trypsin, leucine-aminopeptidase, and alkaline phosphatase activities did not differ between treatments. We conclude that over six weeks of moderate heat stress both abalone species were able to maintain digestive function, but achieved this maintenance in species-specific ways.
Article
Sexual dimorphism in mud crab occurs from the early crablet stage until the crab has the ability to mate. The development of sexual dimorphism is involved in both morphology and physiology. In terms of morphology, the mud crab expressed several characteristics such as the abdomen, chelae, size, weight and reproductive system (gonopore, gonopod and gonad). Regulation of the morphology changes interacts with the physiological process of several hormonal signals such as androgenic gland hormone, crustacean female sex hormone, gonadotropins, methyl farnesoate, neu�rotransmitters and steroids. The sexual dimorphism of economic importance can be observed on male commercial value, which is demonstrated in chelae enlargement, higher weight and rapid growth. Meanwhile, the female crabs offer the pleasant fla�vour of egg masses (ovary) that render the high economic value. These criteria urge the farmers to enhance the profitability through monosex culture, which involves es�tablishing several types of sex manipulation technology (interspecific hybridization, temperature manipulation, hormonal therapy and androgenic gland manipulation). The fundamental knowledge of sexual dimorphism is importantly necessary to the application of sex manipulation technology, which may become the potential solution to optimize the production of crab domestication.