Introduction Abalone Haliotis is a mollusk genus that belonged to gastropod class.. Market demand was high and increased, therefore, abalone was continually exploited and subjected to th
Trang 1Abalone: Introduction, Objectives of study, Materials & Methods, Expected Output,
References
1 Introduction
Abalone (Haliotis) is a mollusk genus that belonged to gastropod
class Abalone was a popular export product It was favorite and luxury food among people in many countries such as Japan, China, Europe Countries United States and Canada Because its delicious meat with high nutritional values
Market demand was high and increased, therefore, abalone was continually exploited and subjected to the reduction of population
(Maliao et al., 2004) The preservation of abalone resources must need
management actions, including the management of fishing, the closure
of fishing region and season, the limitation of work quantity and fishing outcome, or the prevail of quota system (Gulland, 1977) However, cultivation was a solution that was recently coming into consideration
Abalone cultivation was always possible if the seed was available
in constant To obtain the seed in constant, thus, seeding was needed However, a main problem in abalone seeding was lack of availability of broostocks A location that is expected to become the producer of local abalone prime is Namdu Islands, an island cluster in the west coast of Vietnam Coral reefs were surrounding this archipelago
2 Objectives of study
The objectives of study is to determine the biology, growth allometry, minimum size at sexual maturity, to measure fecundity, and to monitor histologically the reproductive cycle of population of the abalone in Namdu archipelago, Kiengiang province
3 Research Methods
Survey on the exploination and resource
A number of 30 survey forms will be distributed independently to the fisherman, who is concerning to the ablone exploination or trade Questionaire will be focused on the change of abalone resource in last 5 years and it will be necessary for the management plans to maitain or develop the ablone prime in Namdu Islands
Biology and reproduction of abalone
Trang 2Sampling will be conducted for one year starting from January 2017 to December
2017 Samples of 20-30 abalones will be collected monthly from a subtidal population at the Namdu archipelago, Kiengiang province to transport alive to the laboratory in Cantho university
Shell length in millimeters, total weight, shell weight, and shucked body weight in grams, sex, and remarks concerning macroscopic features were recorded for each specimen From each specimen, two pieces of conical appendage, consisting of digestive gland and surrounding gonad, will be excised from the tip and the midportion Excised pieces will be fixed and stored in neutral formalin for at least 2 days Tissue will be processed in an Autotechnicon and then stained with Haematocyline and Eosin At least three slides will be processed for each piece of gonad and examined histologically Slides will be observed undermicroscope, the numerial scales of gonad index will be refered
from Hadijah et al (2013) with six differential stages as followed: Immature; Proliferated;
Maturing; Ripe; Partially spawned; Totally spawned
Reproductive biological parameters will be also measured at the laboratory Parameters that will be observed are: (a) sex ratio, (b) gonad microscopic character, (c) gonad maturity rate, (d) gonad maturity index, (e) reproductive cycle, (f) abalone fecundity, (g) Relationship between total fecundity and shell length
Sex ratio will be calculated based on the comparison of male and female samples in every month Macroscopically, abalone gonad was positioned in the right section across the hollowed part of shell At the maturity stage, female gonad was bluish green, while male gonad was whitish cream
Basic environmental conditions
Basic environmental conditions such as temperature, salinity, wind direction, flow rate, structure of bottom sediment, present of seaweeds or aquatic plants will be recorded at the same time with abalone samplings
4 Expected outcomes
i. Basic environmental conditions relating to abalone distribution and
reproduction
ii. Growth allometry
iii. Abalone exploination trends
Trang 3i. Sex ratio (versus sampling period and size classes)
ii. Gonad macroscopic character
iii. Gonad microscopic character
iv. Reproductive cycle
v. Abalone fecundity
5 References
Hadijah, Ambo Tuwo, Magdalena Litaay, Erni Indrawati 2013 The Reproductive
Aspect of Tropical Abalone (Haliotis asinina L.) in the Waters of Tanakeke Islands at
South Sulawesi Aquatic Science and Technology ISSN 2168-9148 Vol 1, No 2: Pages 30-42
Campbell, A., Lessard, J., & Jamieson, G S 2003 Fecundity and seasonal
reproduction of northern abalone, Haliotis kamtschatkana, In Barkley Sound, Canada Journal of Shellfish Research, 22(3): Pages 811-818.
Maliao, R J., Webb, E L., & Jensen, K R 2004 A survey of stock of the donkey’s
ear abalone, Haliotis asinina L in the Sagay Marine Reserve, Philippines: evaluating the effectiveness of marine protected area enforcement Fisheries Research, 66: Pages
343-353
Gulland, J A 1977 Fish population dynamics London: John Wiley and Sons