Abalone Haliotis Asinina Research Articles

Chromosome-scale genome assembly of the tropical abalone (Haliotis asinina)

Abalone (family Haliotidae) are an ecologically and economically significant group of marine gastropods that can be found in tropical and temperate waters. To date, only a few Haliotis genomes are available, all belonging to temperate species. Here, we provide the first chromosome-scale abalone genome assembly and the first reference genome of the tropical abalone Haliotis asinina. The combination of PacBio long-read HiFi sequencing and Dovetail’s Omni-C sequencing allowed the chromosome-level assembly of this genome, while PacBio Isoform sequencing across five tissue types enabled the construction of high-quality gene models. This assembly resulted in 16 pseudo-chromosomes spanning over 1.12 Gb (98.1% of total scaffolds length), N50 of 67.09 Mb, the longest scaffold length of 105.96 Mb, and a BUSCO completeness score of 97.6%. This study identified 25,422 protein-coding genes and 61,149 transcripts. In an era of climate change and ocean warming, this genome of a heat-tolerant species can be used for comparative genomics with a focus on thermal resistance. This high-quality reference genome of H. asinina is a valuable resource for aquaculture, fisheries, and ecological studies.

The Potential of Donkey’s Ear Abalone (Haliotis asinina Linnaeus, 1758) as an Antibacterial Agent and Its Effect on Blood Cholesterol Reduction in Mice (Mus musculus Linnaeus, 1758)

The Potential of Donkey’s Ear Abalone (Haliotis asinina Linnaeus, 1758) as an Antibacterial Agent and Its Effect on Blood Cholesterol Reduction in Mice (Mus musculus Linnaeus, 1758)

Growth and Antibiotic Sensitivity Status of Bacillus spp. associated with Abalone (Haliotis asinina) as Probiotic Candidate Selection

The use of probiotics is an innovation in an effort to increase production and fight pathogens in aquaculture cultivation environments. Probiotic candidate microorganisms are selected selectively to ensure that the probiotics used are safe and provide benefits for the host and the environment. This study aims to select probiotic candidates based on the aspects of growth and sensitivity to antibiotics from 4 isolates of Bacillus from abalone (Haliotis asinina). Growth observations were carried out by turbidimetric method using a spectrophotometer at a wavelength of 600 nm in SWC media, and antibiotic sensitivity was tested using Rifampicin, Gentamicin, Kanamycin, and Erythromycin antibiotics using the well-diffusion agar method. The growth analysis of isolates was described by a growth curve based on the OD value, and antibiotic susceptibility based on the diameter of the inhibition zone. The results showed that the growth of the four isolates of Bacillus spp. had a short lag phase, ranging from 1-2 hours, an exponential phase ranging from 15 hours to B. pumilus SLK1 and B. licheniformis SLK2 isolates, and 12 hours to B. coagulans CaK1 and B. coagulans CaK6 isolates. Antibiotic sensitivity showed that B. coagulans CaK1 isolates were sensitive to all the tested antibiotics, while B. pumilus SLK1 isolates, B. licheniformis SLK2, and B. coagulans CaK6 were only sensitive to Rifampicin and Gentamicin antibiotics. The ideal probiotic candidate is an isolate with good growth and does not have resistance properties, based on the results of this study CaK1 isolate has the potential as a probiotic candidate

Seaweed Gracilariopsis heteroclada, formulated flaked diet, and a combination of both as feed for the abalone Haliotis asinina: effect on growth and survival

Seaweed Gracilariopsis heteroclada, formulated flaked diet, and a combination of both as feed for the abalone Haliotis asinina: effect on growth and survival

Grazing periodicity, grazing rate, feeding preference, and gut examination of early juveniles of abalone Haliotis asinina–fed five benthic diatom species

Grazing periodicity, grazing rate, feeding preference, and gut examination of early juveniles of abalone Haliotis asinina–fed five benthic diatom species

Analysis of Genetic Diversity in Wild and Domesticated Stocks of the Tropical Abalone Haliotis asinina by Microsatellite Polymorphism

The basic information on genetic diversity of wild and hatchery-propagated stocks of tropical abalone, Haliotis asinina is important for the construction of a breeding scheme leading to the sustainable culturing activity of this species. In this study, 2,876 expressed sequence tags (ESTs) were in silico analyzed and 178 EST sequences contained microsatellite motifs. Four loci (DW455, DW503, PHe177, and PT102) of type I and two loci (Haμ9 and Haμ10) of type II microsatellites were applied for genetic diversity studies. The mean number of alleles per locus and observed heterogeneity in wild populations were 4.167 and 0.483, and 4.833 and 0.528 for CAME (east coast) and TRGW (west coast) while those of hatchery-propagated samples were 3.000 and 0.708, 4.500 and 0.479, 5.167 and 0.524, and 6.333 and 0.527 for PHIH (2nd generation, G2; Philippines), SAMH (G1), SMaRT-TRGH (G8) and SMaRT-SICH (G8), respectively. The numbers of alleles, observed heterozygosity and effective population sizes suggested no severe reduction of genetic diversity in our breeding program of H. asinina. However, reduced Ne was observed in the cultured stocks from the Philippines (PHIH). FST-statistics and the exact test between pairs of samples revealed significant genetic differences between all pairwise comparisons of samples in this study.

Flakes versus noodles as feed for the abalone Haliotis asinina , does form matter?

This paper reports the first use of thin flakes (310–315 μm thick) formulated diets as feed for the abalone Haliotis asinina. The study compared noodles and flakes prepared using refined and unrefined diets developed earlier for H. asinina (Bautista-Teruel et al., J. Shellfish Res., 35, 2016, 633). Four treatment diets in triplicates (refined flakes, MBTr-F; refined noodles, MBTr-N; unrefined flakes, MBTur-F; and unrefined noodles, MBTur-N) were used in a feeding experiment conducted in a tank facility. After three months, abalone fed MBTr-F had significantly higher mean shell length and body weight (35.92 ± 0.36 mm, 9.24 ± 0.29 g) compared with those fed MBTr-N (34.63 ± 0.37 mm, 8.22 ± 0.28 g) and MBTur-N (34.23 ± 0.36 mm, 7.66 ± 0.26 g), but did not significantly differ with those fed MBTur-F (35.40 ± 0.30 mm, 8.57 ± 0.24 g). Likewise, abalone fed MBTr-F had significantly higher mean growth rates (5.31 ± 0.08 mm, 2.59 ± 0.06 g/month), compared with those fed MBTr-N (4.90 ± 0.19 mm, 2.26 ± 0.12 g/month) and MBTur-N (4.71 ± 0.02 mm, 2.07 ± 0.06 g/month), but did not significantly differ with those fed MBTur-F (5.11 ± 0.06 mm, 2.37 ± 0.04 g/month). Survival (96.67–98.89%) and FCR (2.2–2.5) did not significantly differ among treatment diets. Between the flaked diets, MBTur-F is the cheaper option. However, the use of this unrefined diet resulted in distinct turquoise abalone shell colour, not observed in those fed MBTr-F.

Market structure of abalone (Haliotis asinina) in Southeast Sulawesi, Indonesia

Abalone is one type of shellfish that has high economic value. This study aimed to assess market structure of abalone. The study was carried out in Bajo Bahari Village in Buton District, and Bau-Bau Municipality. Respondents consisted of 30 abalone catchers in the village, and three village abalone collectors (VACs) and two inter-island abalone traders (IATs) selected using snowball sampling method. Data were collected first in February 2015 and in May 2020 during Covid-19 pandemic. Data were analyzed qualitatively. Market structure was identified through assessment of the nature of competition based on the number of buyers and sellers, product differentiation, and entry and exit barriers. Study results showed that market structure exhibits oligopsony, in which the number of producers are more than that of village collectors, product differentiation is absent, and there exist some barriers to entry for village collectors. During Covid-19 pandemic, fishermen stop catching wild abalone, so there are still no more products to be marketed.

Nursery and grow-out culture of the abalone Haliotis asinina on a reef flat: A comparison of growth and survival using different culture containers

The study was conducted to compare four different culture containers [cage, recycled oil container, tray (control), and tube] in the nursery and grow-out culture of the abalone Haliotis asinina on a reef flat. For nursery culture, early juvenile abalone with mean shell length (SL) of 1.30 ± 0.006 cm and mean body weight (BW) of 0.45 ± 0.007 g were stocked in the containers at 100 ind m−2 and reared until they attained the 3 cm SL size required for grow-out culture in three of the four culture containers. For grow-out culture, juvenile abalone harvested from nursery culture with mean SL of 3.23 ± 0.018 cm and mean BW of 7.33 ± 0.131 g were stocked in the containers at 50 ind m−2 and reared until they were harvestable at 5 cm SL cocktail size in three of the four culture containers. The 3 cm SL grow-out size was attained at 90 days of culture (DOC) in recycled containers, trays, and tubes, while the 5 cm SL cocktail size at 180 DOC in the same containers. Abalone reared in tubes had the highest mean SL after 90 DOC in nursery culture (3.21 cm), while those in trays after 180 DOC in grow-out culture (5.30 cm). However, at the end of the nursery and grow-out culture, there were no significant differences in mean SL among the abalone reared in these three culture containers. In both culture phases, abalone reared in cages had the lowest mean SL, 2.88 and 4.44 cm, respectively. Survival was highest in trays (98.64%) during nursery culture and in tubes (96.57%) during grow-out culture. With comparable results in recycled containers, trays, and tubes for both growth and survival at the nursery and grow-out phases, tubes are recommended for use when culture is to be done on reef flats. Tubes are the most stable and durable among the four culture containers tested. They can withstand strong winds and waves and may be reused for several culture runs.

Bacteriological quality of cage-cultured abalone Haliotis asinina

Abalone is one of the most highly priced seafood delicacies and prepared in various dishes like breaded, soup, steamed and sashimi. They are susceptible to microbial contamination since it is eaten raw sometimes and pathogenic microorganisms can be hazardous to consumers. The present study was carried out to determine the coliform load and the presence of presumptive pathogenic bacteria in cage-cultured abalone in Taytay, Palawan, Philippines. The study was limited to the detection of coliform and some presumptive pathogenic bacteria in different parts of abalone such as gut, gills and mantle. The result of the study revealed that the count of coliforms present in the mantle and gills of abalone falls within the normal standard limit (7 – 21 MPN 100g-1 sample). On the other hand, the gut of abalone was beyond the standard limit (460 MPN 100g-1 sample). Moreover, the gut of abalone harbors Vibrio spp., Salmonella spp. and Shigella spp. and general enteric bacteria. Foodborne infections caused by Vibrio, Salmonella and Shigella are common in Asia.

First Histopathological Description of Parasites and Shell Conditions of the Donkey's Ear Abalone Haliotis asinina (Linnaeus, 1758) Cultured in Marine Cages and Land-Based Tanks in the Philippines

This study is the first attempt to assess parasitic infestations in grow-out cage culture and land-based grow-out tanks of the donkey's ear abalone Haliotis asinina in the Philippines. This histopathological study of the parasites was conducted from 2010 to 2013. Using 30 samples of abalones collected monthly from two sites, samples were measured and fixed in 10% formaldehyde in seawater, and routine histological techniques were used to identify the parasites. Water temperatures of the grow-out floating sea cages and the abalone hatchery facilities whose abalones were collected measured 27.5°C–32.5°C and 26°C–29°C, respectively; salinity in the area of the sea cages was 32–34 ppt, whereas salinity of the abalone hatchery was 32–35 ppt. Examination of the shell from cage-cultured abalones revealed the presence of burrowing polychaetes belonging to the families Serpulidae (prevalence, 32.5%) and Dorvilleidae (prevalence, 30%); on the other hand, only Dorvilleidae (prevalence of 28.5%) was detected in abalones from the hatchery. Histological examination revealed the presence of unknown ciliates (prevalence, 37.5%), Nematopsis sp. (prevalence, 17%), and metacestode Tylocephalum sp. (prevalence, 8.5%) from the grow-out cage-cultured abalones, whereas unidentified ciliates (prevalence, 32.5%) and Nematopsis sp. (prevalence, 10.5%) were detected from hatchery stock. The data collected showed that there was low-intensity infection and prevalence of parasites in abalones from grow-out cages and hatchery. These records of parasites constitute baseline information for future research work on abalones.

Stock enhancement of abalone, Haliotis asinina, in multi-use buffer zone of Sagay Marine Reserve in the Philippines

Donkey's ear abalone (Haliotis asinina) is a gourmet seafood export of the Philippines but its wild stock is at risk due to high fishing pressure. This paper aims to show evidences that abalone seeds produced in hatcheries can be used to rehabilitate its fisheries in multi-use buffer zones of marine reserves. This study released hatchery-reared abalone juveniles in a community-based resource enhancement site located in multi-use reef surrounding Molocaboc. This island is populated by fisherfolks who participated in protecting the 4000 m2 coralline release site. Molocaboc Reef comprise the buffer zone of Sagay Marine Reserve in Negros Occidental province in central Philippines. Data obtained during monthly monitoring of the release site from 2011 to 2016 showed that hatchery-reared abalone established together with its wild counterparts. Baseline wild abalone catch per unit effort (CPUE = 3 divers 1 h fishing) is 0.005/100 m2 in 2011. Mean monthly CPUE after release increased to 53 hatchery-reared and wild individuals combined. The mean shell length, body weight and body mass index of the hatchery-reared individuals (6.4 cm, 70.9 g, 10.5 g/cm) is not significantly different from those of the recovered wild stocks (6.9 cm, 85.0 g, 12.0 g/cm). The stocks recovered in the midst of undisrupted fishing activities in areas immediately outside and beyond the release site. Thus, mass production of seeds of overfished species is advised to repopulate degraded fisheries, improve catch of fisherfolks living within buffer areas of marine reserves and contribute to production and trade of high-value species.

Enriched Ulva pertusa as partial replacement of the combined fish and soybean meals in juvenile abalone Haliotis asinina (Linnaeus) diet

The potential of enriched Ulva pertusa meal as feed ingredient in abalone juveniles, Haliotis asinina was evaluated. Four isonitrogenous and isolipidic diets were formulated which contain 27% protein and 5% lipid. Enriched U. pertusa meal replaced 0% (control), 10%, 20%, and 30% of protein from fish and soybean meals in the formulated diets. Thirty randomly selected abalone juveniles with average weight and shell length of 0.45 g ± 0.01 and 12.71 mm ± 0.01, respectively, were placed in each of the twelve 60-L oval fiberglass tanks equipped with a flow-through seawater system. Abalone were given diets at 3–5% body weight daily for 120 days in three replicate samples. Results showed no significant differences (p > 0.05) in percent weight gain, shell length, specific growth rate, feed conversion ratio, and protein efficiency ratio even up to 30% replacement level. Apparent dry matter digestibility of U. pertusa meal in abalone diet was 92%. Crude protein content of the abalone fed diets 1 (10% enriched U. pertusa meal) and 3 (30% enriched U. pertusa meal) was significantly (p < 0.05) higher than those fed on basal diet. Enriched U. pertusa meal can partially replace fish and soybean meals as protein source in formulated diets for abalone, Haliotis asinina juveniles.

Survey on the Predators of Abalone Haliotis asinina from the Perspective of the Local Fisherfolks in Selected Sites of Palawan, the Philippines

The abalone Haliotis asinina is among the highly valued aquaculture commodities in the Philippines. But, the production of abalone in general has declined primarily because of unregulated exploitation. Predation, both in the wild and in grow-out cages may also contribute to the decrease of abalone production. As there has been no record on the predation of H. asinina in the past, this study is the first to gather information on the predators of this species, taken from the perspective of local fisherfolks. Four sites in Palawan Island, the Philippines, identified to have active gathering of wild abalone were sampled. Descriptive survey method with a semistructured questionnaire was used to interview local fisherfolks regarding their knowledge on predators of abalone. A total of 84 respondents were interviewed of which 53 have observed actual predation of abalone. Twenty-five species of predators composed of fishes, crustaceans, molluscs, an octopus, and a sea turtle have been identified. Of this, four species, namely, the fishes Cyclichthys orbicularis and Diodon liturosus, Octopus sp., and the crab Charybdis feriata were consistently observed in the four sites based on the synthesis of data obtained from the fisherfolks. Most respondents suggest that aquaculture is an essential way to increase the abalone production. The information herein serves as baseline information to develop appropriate design and management of culture facility to minimize predation and to maximize the survival of cultured abalone. Further study on the ecology, particularly the actual observation of predation and its effects, is recommended.

Microbial and Microparasite Abundance in Cage-Cultured Abalone Haliotis asinina

Microorganisms and parasites are some of the major threats to aquaculture, including abalone culture worldwide; however, few reports concerning these microbes and parasites in abalone have been published. Moreover, several studies were conducted to determine the microbial load and degree of parasitism in abalone of other species but not the abalone Haliotis asinina of the Philippines, particularly in Palawan. This study was conducted to assess the abundance of microorganisms and microparasites in the cage-cultured abalone. The microbial abundance was determined by dilution plate count technique. Slide sampling and scoring was performed using methylene blue and acetocarmine stains to determine the abundance of microparasites. Results revealed that fungi have the highest total abundance among the four functional groups of microorganisms present in abalone. The Gram-positive bacteria had the highest abundance in the digestive tract (178 × 103 CFU/g). Actinomycetes had the highest abundance in the gonad (35 × 103 CFU/g). On the other hand, fungi had the highest abundance in the gills (198 × 103 CFU/g) and in the mantle (95 × 103 CFU/g). The highest abundance of microorganisms was found in the digestive tract of abalone. Microparasites such as trematodes, nematodes, copepods, and protozoans were found in cage-cultured abalones. Among these microparasites, trematodes were found abundant in the gills, whereas protozoans were abundant in the stomach of abalones.

Isolation and Characterization of Antimicrobial-Producing Bacteria from the Donkey's Ear Abalone Haliotis asinina

This study was conducted to isolate, test the antimicrobial potential, and characterize bacterial isolates from the gut of Haliotis asinina collected from cage culture and wild population. Isolation was performed using dilution spread plate method and antimicrobial property was determined using streak plate method against nine test microorganisms. Results showed that of the 29 isolates from the cage-cultured samples, five isolates showed the presence of antimicrobial property against Escherichia coli, Staphylococcus aureus, Bacillus cereus, Bacillus subtilis, Bacillus megaterium, Pseudomonas aeruginosa, and Candida albicans. Among the 30 isolates from the wild-caught samples, six isolates showed the presence of antimicrobial potential when tested against E. coli, S. aureus, B. cereus, B. subtilis, B. megaterium, and C. albicans. None of the isolates inhibited Aspergillus niger or Aspergillus flavus. The bacterial strain coded C28, isolated from cage-cultured abalone, and that inhibited the most test microorganisms was subjected to cultural, morphological, and physiological characterization. It was characterized as a bacterial strain closely related to the genus Pseudomonas. The results suggest that bacteria in the gut of H. asinina have potential antimicrobial properties where bacteria related to Pseudomonas spp. are present.

CO2-induced pH Reduction Hinders Shell Development of Early Larvae Donkey's Ear Abalone Haliotis asinina (Linnaeus 1758)

CO2-induced pH Reduction Hinders Shell Development of Early Larvae Donkey's Ear Abalone Haliotis asinina (Linnaeus 1758)

REPRODUCTIVE ASPECTS OF THE TROPICAL ABALONE, HALIOTIS ASININA, FROM SOUTHERN LOMBOK WATERS, INDONESIA

The main objective of this study was to determine reproductive strategy including major spawning season of tropical abalone (Haliotis asinina) from southern Lombok waters, Indonesia. Gonad bulk index, maturity stages and oocyte size frequency distribution were applied to document gonadal development and major spawning season. The results of this study show that H. asinina in southern Lombok waters displayed year-round spawning with a high proportion occurring in August - November, when gonad index dropped to a lower level and high proportion of partly spawned and/or spent ovaries occurred in the population. Gonad development and spawning in males and females occurred synchronously. The correlation between gonadal development and environmental factors are described and discussed.

BROODSTOCK CONDITIONING FOR THE TROPICAL ABALONE (Hatiotis asinina) UNDER DIFFERENT COMBINATION OF PHOTOPERIOD AND WATER TEMPERATURE

The main purpose ot this study is to understand the influcnce of external parameters, i.e, photoperiod and water temperature, on gonadal maturation of tropical abalone (Haliotis asinina) in southorn Lombok waters, NTB

ANALISIS PENDAPATAN DAN PROSPEK AGRIBISNIS ABALON (HALIOTIS ASININA) DI KABUPATEN KONAWE DAN KOTA KENDARI

Abalone (Haliotis asinina) is one of the economically valuable commodities of fishery. Abalon products have a high prices and market demand especially to export. This condition, abalone businesses should get a high income for them. The research was to analyze the abalone business doer in each level and developing prospect of abalone agribusiness in Southeast Sulawesi based on the relationship between agribusiness sub-system and the income gained. Respondents and population of research was the whole abalone business comprised of fishermen, cultivator, collector venders, and inter venders. Descriptive analysis is used to find out the relationship of abalone agribusiness sub-system, while income analysis is used to find out the income of abalone agribusiness. To see the prospect of abalone agribusiness the analysis of descriptive and income is used. Result of the research shown that the relationship of abalone agribusiness has not well integrated. The income gained by fishermen per season is Rp.309.211,- , and the collector vender is Rp.9.830.734,-, while the income of inter vender of province is Rp.12.282.976,-. From the result of the analysis can be concluded that abalone agribusiness has an average prospect to be developed in Konawe Regency.Keywords: abalone, agribusiness, income analysis, prospect of abalone