aquaculture nutritionm.2011.pdf · give true (self-supporting) gels, but will form strong and...

1 1 2 1,3

1 Aquaculture & Fisheries Development Centre, School of Biological, Earth & Environmental Sciences, University College Cork,

Distillery Fields, North Mall, Cork, Ireland; 2 Kerry BioScience Ltd., Kilnagleary, Carrigaline, County Cork, Ireland;3 Department of Zoology, Ecology & Plant Science, School of Biological, Earth & Environmental Sciences, University College

Cork, Cork, Ireland

As part of a programme to develop sustainable diets for

macroalgivores, a 3-month experiment was conducted to

determine the effects of konjac glucomannan–xanthan gum

(KX) binder configuration on formulated feed stability, feed

palatability and growth performance of juvenile, hatchery-

reared, Haliotis discus hannai. This study was conducted in a

recirculation facility in which four KX binder configurations

were evaluated in a series of isonitrogenous experimental

feeds and freshly harvested Laminaria digitata was included

as a natural feed type. Dry matter leaching of the experi-

mental feed treatments was assessed with no significant dif-

ference in the dry matter leaching between treatments

observed. No differences (P > 0.05) were found in percent-

age survival, daily food consumption (DFC) and linear

growth rate (LGR) between treatments. Food conversion

efficiency (FCE), specific growth rate (SGR) and body

weight/shell length (BW/SL) ratio were significantly higher

when offered L. digitata. Trends showed that the best per-

forming KX feed in terms of FCE, LGR, SGR and BW/SL

ratio was produced with the 2% KX; 1 : 1 binder.

KEY WORDSKEY WORDS: abalone, binder, feed production, growth, Hali-

otis, nutrition

Received 4 March 2010, accepted 2 July 2010

Correspondence: Maria O�Mahoney, Aquaculture & Fisheries Development

Centre, University College Cork, Distillery Fields, North Mall, Cork,

Ireland. E-mail: [email protected]

It is widely accepted that aquaculture is pivotal to the future

maintenance of commercial fishery markets. Key challenges

that are faced by the industry include issues of sustainability,

feed availability and technological challenges to improve

production efficiency. For abalone culture, commercial feeds

exist, but the low uptake by producers in Ireland continues to

put pressure on local marine ecosystems because natural

harvests of marine kelp continue to be used as the primary

feed source. When harvested sustainably, i.e. a stump of

25 cm is left intact; regeneration can take 3–5 years (Werner

& Kraan 2004). However, the impact of locally intensive

harvesting of near-shore kelp beds can result in slow regen-

eration times and altered community structure (Kelly 2005).

Multiple stakeholders in the aquaculture sector in Ireland

have nominated feed development and availability as a

priority research focus for this sector. This research was

conducted as part of a feed development programme for high

value shellfish species in Ireland.

Recent FAO statistics indicate that world capture produc-

tion of abalone has declined in all producing countries. Max-

imal output of abalone aquaculture existed in just two of

the thirteen producing countries, China and Korea, in 2007

(FAO 2009). The high market value of abalone suggests that

intensification of commercial abalone culture is necessary to

sustain market demands. A diet that reduces the reliance on

non-sustainable feed sources is critical to commercial viability.

Target nutritional requirements for several commercially

lucrative species of abalone have been identified through

considerable research in recent decades. Regionally devel-

oped artificial feeds exist for locally produced species, and

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� 2011 Blackwell Publishing Ltd

2011. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

doi: 10.1111/j.1365-2095.2010.00816.x

Aquaculture Nutrition

a number of feeds produced by extrusion cooking are

available. However, high importation costs have restricted

widespread use of currently available feeds in some regions.

The application of cost-effective, innovative feed production

technologies is necessary to achieve a locally dynamic and

internationally competitive aquaculture industry.

Binder configuration is important for abalone feed devel-

opment because of the perceived influence on feed palat-

ability. A review by Fleming et al. (1996) outlined the pivotal

role of feed binders in commercially focussed artificial feed

development for abalone. For abalone, previous studies have

shown that binder strength and feed palatability are nega-

tively correlated (Uki et al. 1985; Gorfine 1991). Similarly, a

negative relationship between consumption and feed tough-

ness has been demonstrated for Haliotis rubra and Haliotis

midae offered natural macroalgae species (Day & Cook 1995;

Fleming 1995). Coupled with this, leaching of feed attrac-

tants from artificial feeds is desirable in intensive culture

whereby the naturally passive feeding nature of abalone may

benefit from stimulation (Harada et al. 1996; Mai 1998;

Fermin 2003; Troell et al. 2006).

Hydrocolloids (e.g. gelatin, guar gum, sodium alginate,

agar, carrageenan, carboxymethylcellulose) as feed binders

are advantageous for artificial feed production because they

are easy to produce in small scale, and the effectiveness of

hydrocolloid-bound on-growing feeds has been demonstrated

for several aquatic species such as shrimp (De Muylder et al.

2008; Palma et al. 2008), sea urchins (Caltagirone et al. 1992;

Pearce et al. 2002; Mortensen et al. 2003), abalone (Uki et al.

1985; Knauer et al. 1993; Britz 1996a; Coote et al. 1996),

tilapia (Fagbenro & Jauncey 1995), crayfish (Ruscoe et al.

2005), sole (Liu et al. 2008) and rainbow trout (Storebakken

& Austreng 1987). However, some hydrocolloid binders such

as gelatin and sodium alginate are expensive, and their use in

formulated feed development may be prohibitive to overall

low-cost feed production goals. Other hydrocolloid binders

are more cost-effective as feed binders, and applications of

these binders have often been demonstrated in other areas.

Two such binders are konjac glucomannan and xanthan gum.

Konjac is a glucomannan polysaccharide obtained from the

tubers of Amorphophallus konjac and has a linear backbone

of (1 fi 4)-linked b-D-mannose and b-DD-glucose, in the ratio

1.6 : 1 (Kato & Matsuda 1969). Solubility is conferred by the

presence of acetyl groups (approximately, 1 acetyl group per

17 residues) at the C-6 position, and short oligosaccharide

side chains at the C-3 position of the mannoses. Xanthan

gum is an extracellular polysaccharide derived from the

bacterium, Xanthomonas campestris, which is a naturally

occurring pathogen of the brassicas (Kelco 2007). Xanthan

gum has a (1 fi 4)-linked linear backbone of b-D-glucose, as

in cellulose, and is solubilized by charged trisaccharide side

chains attached at O-3 of alternate glucose residues to give a

pentasaccharide repeating sequence (Melton et al. 1976). On

cooling and/or addition of salt, it undergoes a co-operative

conformational transition (Morris et al. 1977) from a disor-

dered coil to a rigid ordered structure (5-fold helix). Solutions

of xanthan gum in its ordered conformation show tenuous

‘‘weak gel’’ properties, which appear to arise from weak

association between the helical sequences, and are sensitive to

ionic environment. Xanthan gum alone, however, does not

give �true� (self-supporting) gels, but will form strong

and cohesive gels when mixed with konjac glucomannan

(Goycoolea et al. 1995). The exact mechanism of gel forma-

tion is not yet established, but probably involves association

of �smooth� regions of the (1 fi 4)-diequatorially linked of

konjac glucomannan to the cellulosic backbone of xanthan

(also (1 fi 4)-diequatorially linked). The formation of rec-

ognizable gels was found at total polysaccharide levels of only

0.02%, which is the lowest gelling concentration observed for

a carbohydrate system (Dea 1993). Both konjac glucomannan

and xanthan gum have been widely used in the food industry.

The formation of the gel network in the presence of the feed

physically entraps the material. Any interactions with the

components contained within the feed would result in the

compromised formation of this network. Applications of the

konjac glucomannan–xanthan gum binders have been dem-

onstrated in other areas (e.g. pharmaceutical and prosthetics)

(Eyo-okon & Hilton 2003; Alvarez-Mancenido et al. 2008;

Fan et al. 2008), but this binder complex has not previously

been evaluated for aquatic feed production.

Considerable development studies of the konjac gluco-

mannan–xanthan gum (KX) binder for use in aquatic feeds

has identified three major variables in the KX binder con-

figuration for artificial feeds (i) the use of seawater (SW) or

distilled water (DW) in binder preparation, (ii) overall binder

concentration and (iii) the ratio of K to X (O�Mahoney

2009). The aim of this study was to assess a formulated feed

with four forms of the KX binder on feed palatability and the

growth performance of cultured Haliotis discus hannai. The

results of this study were pivotal to further feed development

for H. discus hannai using the KX binder.

Konjac glucomannan (KJ2B) was obtained from Mannasol

Products Ltd (Cheshire, UK) and xanthan gum (Keltrol [E])

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Aquaculture Nutrition � 2011 Blackwell Publishing Ltd

was obtained from CP Kelco (Surrey, UK). Laminaria digi-

tata meal was obtained from Arramara Teoranta (Co. Gal-

way, Ireland), soy protein isolate was obtained from Holland

and Barrett (Cork, Ireland), CaCO3 was obtained from

Sigma-Aldrich Ltd (Dorset, UK), and vitamins and minerals

were obtained from Inform Nutrition (Cork, Ireland).

Experimental feeds in this study were prepared according

to recently developed methodology for feed production

using the konjac glucomannan–xanthan gum binder

(O�Mahoney 2009). Dry feed ingredients were mixed for

10 min in a commercial food mixer. The konjac glucoman-

nan and xanthan gum powders were weighed out in separate

batches at the required concentration and mixed to com-

bine. The total volume of water (SW or DW) required was

placed in a stainless steel pot with a mixing paddle, and the

mixed powders were dispersed using a fine dredger. When

all the powders were dispersed, mixing was continued for

30 min. The viscous solution was placed in a hot water

bath (set temperature 85 �C) and heated for 30 min after a

minimum internal gel temperature of 72 �C was reached.

Dry feed ingredients and lipids were added to the hot gel

solution, and the composite feed was mixed in a commercial

food mixer for 3 min. The hot feed was poured into a rigid

container, cooled rapidly and refrigerated overnight. On the

following day, the feeds were sliced into strips and air-dried

in a drying room equipped with a convector heater and

dehumidifiers for 24–30 h (average temperature 30 �C;average relative humidity 28%). Air-dried feeds were stored

in air-tight containers.

To evaluate the key parameters of the KX binder config-

uration and the implications for H. discus hannai culture, an

experimental growth trial consisting of the following feed

treatments was conducted:

• Laminaria digitata

• 2% Distilled water K:X (1 : 3) (Diet A: DW 2% KX

1 : 3).

• 2% Seawater K:X (1 : 3) (Diet B: SW 2% KX 1 : 3).

• 2% Seawater K:X (1 : 1) (Diet C: SW 2% KX 1 : 1).

• 1.5% Seawater K:X (1 : 1) (Diet D: SW 1.5% KX 1 : 1).

The dietary treatments and feed ingredient composition

are shown in Table 1. Proximal composition and energy

composition of the feed treatments are shown in Table 2.

Table 1 Ingredient composition of the

experimental feeds (g dry matter kg)1)Ingredients

Diet A

(DW 2%KX; 1 : 3)

Diet B

(SW 2%KX; 1 : 3)

Diet C

(SW 2%KX; 1 : 1)

Diet D

(SW 1.5%KX; 1 : 1)

KX binder 174.7 174.7 174.7 174.7

Laminaria

digitata meal

319.7 319.7 319.7 319.7

Soy protein isolate 352.9 352.9 352.9 352.9

CaCO3 107.2 107.2 107.2 107.2

Vitamins1 14.9 14.9 14.9 14.9

Minerals2 30.6 30.6 30.6 30.6

DW, distilled water; KX, konjac glucomannan–xanthan gum; SW, seawater.1 Vitamin premix composition per kg of experimental feed (Mai et al. 1995a) : thiamine HCl

120 mg; riboflavin 100 mg; folic acid 30 mg; PABA 400 mg; pyridoxine HCl 40 mg; niacin 800 mg;

Ca pantothenate 200 mg; inositol 4000 mg; ascorbic acid 4000 mg; biotin 12 mg; vitamin E

450 mg; menadione 80 mg; vitamin B12 0.18 mg; vitamin A 100 000 IU; vitamin D 2000 IU;

ethooxyquin 400 mg.2 Mineral premix per kg of experimental feed (Mai et al. 1995a; Tan et al. 2001) : NaCl 0.4 g;

MgSO4.7H2O 6.0 g; NaH2PO4.2H2O 10.0 g; KH2PO4 20 g; Ca(H2PO4)2.H2O 8.0 g; ferric citrate

1.0 g; ZnSO4.7H2O 141.2 mg; MnSO4.2H2O 64.8 mg; CuSO4.5H2O 12.4 mg; CoCl2.6H2O 0.4 mg;

KIO3 1.2 mg; Na2SeO3 0.4 mg.

Table 2 Proximal composition of the

feed treatments (g kg)1 of dry matter)

Component

Diet A

(DW 2%KX;

1 : 3)

Diet B

(SW 2%KX;

1 : 3)

Diet C

(SW 2%KX;

1 : 1)

Diet D

(SW 1.5%KX;

1 : 1)

Laminaria

digitata

Protein1 387.6 361.0 361.3 357.0 148.4

Ash1 303.0 363.0 360.0 362.6 285.1

Carbohydrate1 306.4 275.2 278.3 276.5 516.3

Fat1 3.1 0.9 0.4 3.9 50.2

Energy2 11.74 10.68 10.72 10.75 13.02

DW, distilled water; KX, konjac glucomannan–xanthan gum; SW, seawater.1 Values given as g kg)1 of dry matter.2 Energy values in kJ g)1.

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Hatchery-produced H. discus hannai [20–30 mm shell length

(SL)], which were reared on L. digitata, were collected from

Brandon Bay Seafoods, County Kerry, Ireland in February

2008 and transported to the Aquaculture & Fisheries

Development Centre, University College Cork (AFDC,

UCC) in large, cable-tied plastic bags that were dampened

internally with SW and pumped with oxygen to reduce gill

desiccation and aerobic stress (Sales & Britz 2001). Abalone

were maintained on a ration of L. digitata at the AFDC for

2 weeks to acclimate to the change in conditions.

The experimental system in this study consisted of a recir-

culation culture system consisting of 15 independent rectan-

gular plastic tanks (320 mm L · 175 mm W · 150 mm H),

each containing a rearing unit composed of aquamesh lined

with corrugated plastic inserts. Each tank was aerated with a

centrally positioned airstone. The experimental system was

enclosed within a black surround such that abalone were

maintained in constant darkness throughout the study based

on evidence in Garcia-Esquivel et al. (2007). Outflow from

each tank was recirculated through a 2500- L SW reservoir

known as the Global Oceans System. Aeration in the SW

reservoir was maintained through a series of airlines lining

the base of the Global Oceans floor.

Water quality in the Global Oceans system was maintained

by weekly renewal of 50% of the SW capacity. Inflow into

the experimental tanks was monitored weekly using a

Palintest� photometer to measure levels of ammonia

(0.18 ± 0.048 mg L)1 N), nitrite (0.02 ± 0.005 mg L)1 N),

nitrate (0.22 ± 0.034 mg L)1 N), pH (8.23 ± 0.004) and

alkalinity (186.67 ± 4.495 mg L)1 CaCO3). Salinity was

monitored on a weekly basis using a hand-held refractometer

and averaged at 35.5 ± 0.230 g L)1. SW temperature and

dissolved oxygen was monitored using the OxyGuard System

(OxyGuard, Birkerod, Denmark) and averaged at 17.33 ±

0.321 �C and approximately 10.1 ± 0.08 mg L)1, respec-

tively, over the duration of the study.

After the two week acclimation period, the H. discus hannai

were starved for 7 days prior to the initiation of the experi-

ment. Individuals were drained of excess surface moisture

prior to measuring for individual SL (±0.1 mm) and weight

(±0.01 g) and randomly divided between 15 experimental

tanks (n = 15 tank)1). The initial stocking parameters of

each tank were 25.89 ± 0.18 mm SL and 2.79 ± 0.06 g live

weight (mean ± SE).

This study consisted of five experimental treatments of

which four feeds were novel formulated KX feeds. The

control treatment was fed locally harvested L. digitata. Three

replicates of each feed treatment were conducted. The

experimental set-up allowed interchanges of tank position at

each feeding interval for a completely randomized experi-

mental design.

Feed replenishment was conducted every 3/4 days and aba-

lone were fed ad libitum. Dry matter conversion factors for

the artificial feeds being fed throughout the trial were

obtained by drying five random samples of each diet in the

oven at 105 �C overnight at the beginning of the experiment.

Fresh L. digitata was obtained from Ballycotton Bay, Co.

Cork approximately every 7–10 days and stored in an aer-

ated SW tank at the AFDC. The L. digitata was removed

from the SW as required, and all epiphytes were removed. At

each feeding interval, a sample of the L. digitata frond used

in feeding was dried in an oven (n = 3) at 105 �C for 24 h to

obtain a dry matter conversion factor for that feed. All

conversion factors for day 0 feeds were calculated as follows:

C ¼ d=w

where C = conversion factor, d = dry weight of the feed (g)

and w = wet weight of the feed (g).

Control samples (triplicate) of fresh L. digitata were run at

each feeding interval to correct for loss in macroalgal bio-

mass in the absence of abalone. Correction factors for KX

feed consumption were determined from a dry matter

leaching assessment conducted at the end of the experiment.

Daily feed consumption rates (DFC) and food conversion

efficiencies (FCE) were calculated using the formula:

DFC ¼ ½ðFg � FuÞ=t�=ðW Þ

where the DFC was the daily food consumption (DFC)

(mgdry matter g)1

abalone day)1), Fg was the dry weight (g) of

food given during the experimental period, Fu was the dry

weight (g) of food uneaten during the experimental period,

W was the mean wet weight of abalone during the experi-

mental period (assuming linear growth) and t was the time in

days. FCE was calculated from the formula:

FCE ¼ 100ðWf � WiÞ=ðFg � FuÞ

where FCE was the food conversion efficiency (%), Wf and

Wi were the final and initial whole abalone wet weights (g),

Fg was the dry weight of food given (g) during the experi-

mental period, Fu was the dry weight of food uneaten (g)

during the experimental period.

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Initial and final biometric data (length; mm and weight; g)

were recorded during this study to minimize the impact of

sampling intervals on overall H. discus hannai health and

homeostasis (Sales & Britz 2001). Growth rate was calculated

in terms of (i) SL (linear growth rate; LGR) and (ii) total

weight (specific growth rate; SGR) using the following

equations:

LGR ðmm SL day�1Þ ¼ ðLf � LiÞ=t

SGR ð%day�1Þ ¼ 100ðlnWf � lnWiÞ=t

where Li and Wi are initial length and weight, respectively,

Lf and Wf are the final length and weight, respectively, t is

the time (days) and ln is the natural log.

The body weight to SL ratio (BW/SL) was calculated at

the beginning of this study and for all experimental treat-

ments at the end of the study using the equation:

BW : SL ðg mm�1Þ ¼Mean weight=mean length

Each tank was checked for mortalities at each feeding

interval. Overall percentage survival (St) was calculated as

the ratio of the number of individuals surviving at the end of

experiment to the number of individuals at the beginning of

the experiment using the equation:

St ¼ Nt=No�100

where Nt is the number of abalone surviving at the end of

the experiment, and No is number of abalone at the

beginning of the experiment.

Tests to determine the dry matter leaching of the feed

treatments in this study in the absence of abalone were

conducted over 3/4 days at the end of this study in the

experimental system vessels. The dry matter loss values of the

formulated KX feeds were used for corrected consumption

estimates in this study.

The aquaria were labelled with the diet treatments of this

study (n = 3). Into each tank, two pieces of the appropriate

feed were placed. Each feed piece was preweighed and

labelled with a twine tag corresponding to the days of the

stability test (1st and 2nd). On day 0 of the stability test, dry

matter conversion factors for the feeds in the stability test

were obtained using identical procedures to those outlined

earlier (see Feeding, consumption and growth). These values

were used to calculate the average dry matter (g) in each feed

piece used in the SW stability test. On each day, the feed

piece with the label corresponding to that day number (1–2)

was removed from the aquaria, drained on absorbent paper,

weighed and oven-dried at 105 �C for 24 h to determine the

dry weight (g) of the feed piece. The dry matter leaching

(g kg)1) on each day was calculated using the equation:

Dry matter loss ðg kg�1Þ ¼ ðDo � DmÞ=Do � 103

where, Do is the dry matter (g) in the original feed piece, Dm

is the dry matter (g) in the final feed piece after immersion in

SW.

Tank position was randomized throughout the experiment,

and the possibility of tank effects was assessed using a

randomized ANOVAANOVA at the end of the experiment. The

assumptions of normality were analysed using the

Kolmogorov–Smirnov or Shapiro–Wilks test. Comparisons

between groups of normal data were tested using ANOVAANOVA.

Non-normal data were compared using the non-parametric

Kruskal–Wallis test. Post hoc analyses were conducted using

the TUKEY multiple comparison test and the Kruskal–

Wallis multiple comparison test. All statistical analyses were

conducted using SPSSSPSS (Ver. 12.0.1 for Windows, SPSS Inc.,

Chicago, IL, USA). Significance was assumed when P < 0.05.

The initial abalone length and weight (mean ± SE) are

shown in Table 3. A one-way ANOVAANOVA indicated that there was

Table 3 Initial abalone stocking parameters (mean ± SE; n = 15)

Tanks Length (mm) Weight (g)

1 26.23 ± 0.796 2.97 ± 0.275

2 26.27 ± 0.846 2.97 ± 0.275

3 26.06 ± 0.759 3.01 ± 0.282

4 25.54 ± 0.821 2.68 ± 0.231

5 25.47 ± 0.683 2.57 ± 0.193

6 26.13 ± 0.539 2.80 ± 0.173

7 25.34 ± 0.818 2.75 ± 0.296

8 25.94 ± 0.772 2.94 ± 0.256

9 25.69 ± 0.668 2.59 ± 0.214

10 25.95 ± 0.729 2.75 ± 0.238

11 25.74 ± 0.729 2.81 ± 0.256

12 25.77 ± 0.533 2.63 ± 0.158

13 26.13 ± 0.626 2.87 ± 0.226

14 25.95 ± 0.752 2.69 ± 0.193

15 26.14 ± 0.831 2.79 ± 0.239

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no significant difference in the mean weight of each treatment

(ANOVAANOVA; d.f. = 4, 224; F = 0.722; P = 0.578).

The possibility of tank effect was tested at the end of the

experiment by randomized complete block ANOVAANOVA with tank

as a factor. Tank effect was non-significant (P > 0.05).

Immersion in SW resulted in dry matter loss in all experi-

mental treatments (Table 4).

On day 3, no significant differences in cumulative dry

matter leaching between treatments were observed (Kruskal–

Wallis; d.f. = 4; H = 8.433; P = 0.077). On day 4, dry

matter loss across all treatments was not significantly dif-

ferent (Kruskal–Wallis; d.f. = 4; H = 7.833; P = 0.098).

At the end of the experiment, mean per cent survival ranged

from 91.11 ± 5.9% for Diet A treatment to 100.00 ± 0.0%

for abalone fed L. digitata (Table 5). There were no signifi-

cant differences in the survival rates between treatments

(Kruskal–Wallis, d.f. = 4; H = 6.030, P = 0.197).

Mean DFC rates (mg DM g abalone)1 day)1) ranged from

5.43 ± 0.2 mg (L. digitata) to 8.26 ± 1.4 mg (Diet A).

There were no significant differences in the DFC of H. discus

hannai between treatments (ANOVAANOVA; d.f. = 4, 14; F = 3.074;

P = 0.068) (Fig. 1).

Laminaria digitata had a significantly higher FCE (6.79 ±

0.4% day)1 dry matter feed to wet weight gain) than the KX

experimental feeds in the current study (ANOVAANOVA; d.f. = 4, 14;

F = 43.707; P = 0.000) (Fig. 2). Within the KX feed

treatments, there was no significant difference in the observed

FCE.

Linear growth rate (LGR) No significant difference in the

LGR between the experimental treatments was observed

(ANOVAANOVA; d.f. = 4, 14; F = 3.537; P = 0.05) (Fig. 3). LGRs

ranged from 0.022 ± 0.001 mm day)1 (Diet D) to 0.058 ±

0.02 mm day)1 (L. digitata).

Specific growth rate (SGR) Laminaria digitata had the

highest SGR (0.56 ± 0.05% day)1) in this study, which was

significantly different to the novel KX feed treatments

(ANOVAANOVA; d.f. = 4, 14; F = 19.820; P = 0.000) (Fig. 4).

Within the novel feed treatments, SGR ranged from 0.14 ±

0.02% day)1 (Diet A) to 0.23 ± 0.07% day)1 (Diet C).

Table 5 Percentage survival (mean ± SE; n = 3) of Haliotis discus

hannai in this study

Treatment Survival (%)

Laminaria digitata 100.00 ± 0.0

Diet A (DW 2%KX; 1 : 3) 91.11 ± 5.9

Diet B (SW 2%KX; 1 : 3) 91.11 ± 3.9

Diet C (SW 2%KX; 1 : 1) 95.56 ± 3.9

Diet D (SW 1.5%KX; 1 : 1) 95.56 ± 3.9

DW, distilled water; KX, konjac glucomannan–xanthan gum; SW,

seawater.

Table 4 Cumulative dry matter leaching (g kg)1; mean ± SE;

n = 3) of the experimental diets in this study

Treatment Day 3 Day 4

Laminaria digitata 224.5 ± 39.9 303.4 ± 12.7

Diet A

(DW 2%KX; 1 : 3)

459.6 ± 65.0 419.4 ± 57.3

Diet B

(SW 2%KX; 1 : 3)

336.7 ± 26.0 404.1 ± 20.1

Diet C

(SW 2%KX; 1 : 1)

332.4 ± 13.8 489.5 ± 78.9

Diet D

(SW 1.5%KX; 1 : 1)

350.8 ± 5.3 472.5 ± 25.7


seawater.

Experimental parameters over the duration of the stability test

were : temperature (�C) = 16.24 ± 0.075; pH = 8.25 ± 0.002; O2

(mg L)1) = 10.5 ± 0.3.

0

2

4

6

8

10

12

Diet A Diet B Diet C Diet D

Diet

DFC

(mg

DM

g a

balo

ne–1

day

–1)

L. digitata

Figure 1 Daily food consumption (DFC) (mgdry matter g)1abalone

day)1; mean ± SE; n = 3) of each treatment. Differences in the

DFC between experimental treatments were non-significant (ANOVAANOVA,

d.f. = 4, 14; P = 0.068).

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Body weight/shell length ratio (BW/SL) Significant differ-

ences in the BW/SL ratios were evident in this study (Krus-

kal–Wallis; d.f. = 5; H = 15.822; P = 0.007) (Table 6).

The BW/SL ratio increased in all treatments when compared

with the initial BW/SL ratio (0.108 ± 0.001 g mm)1) but

Diet A (0.109 ± 0.002 g mm)1) did not show a significant

increase in BW/SL ratio over the duration of the study.

Laminaria digitata had the highest increase in BW/SL ratio

(0.155 ± 0.001 g mm)1) and was significantly higher than all

other experimental treatments at the end of this study. Diet C

(0.119 ± 0.007 g mm)1) had the highest BW/SL ratio of the

experimental KX feeds. This value was significantly different

to Diet A but not significantly different to Diet B

(0.114 ± 0.004 g mm)1) or Diet D (0.115 ± 0.001 g mm)1).

The results of the dry matter leaching assessment indicated

that dry matter leaching for the KX feeds did not differ

significantly to the control treatment, L. digitata. Varying the

concentration of KX and K to X ratios did not have a sig-

nificant effect on dry matter leaching in this study. It was

perceived that four days is the maximum duration for SW

stability for these feeds because removal of these feeds after

day 4 was hindered by feed disaggregating. Grazing is a slow

0

0.01

0.02

0.03

0.04

0.05

0.06

0.07

0.08


–1

L. digitata

Figure 3 Linear growth rate (LGR) (mm shell length day)1;

mean ± SE; n = 3) of the experimental feeds in this study. There

was no significant difference in the observed LGR between treat-

ments (ANOVAANOVA; d.f. = 4, 14; P = 0.05).

b

b

bb

a

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

Diet A Diet B Diet C Diet DDiet

SGR

(% d

ay–1

)

L. digitata

Figure 4 Specific growth rate (SGR) (% day)1, mean ± SE, n = 3)

of the experimental treatments in this study. SGR was significantly

different between treatments (ANOVAANOVA; d.f. = 4, 14; P = 0.000). The

results of the Tukey HSD are indicated by letters above the bars.

Where letters are not in common between bars indicates significant

differences between treatments (P < 0.05).

bb

bb

a

0

1

2

3

4

5

6

7

8


FCE

(% d

ay–1

)

L. digitata

Figure 2 Food conversion efficiency (FCE) (% day)1 dry matter feed

to wet weight gain; mean ± S.E.; n = 3). Results showed that sig-

nificant differences in the FCE were evident between Laminaria

digitata and the experimental KX feeds (ANOVAANOVA; d.f. = 4, 14;

P = 0.000). The results of the Tukey HSD are indicated by letters

above the bars. Where letters are not in common between bars

indicates significant differences between treatments (P < 0.05).

Table 6 Body weight/shell length (BW/SL) ratios (mean ± SE;

n = 3) of the initial data and final dietary treatments of this study

Treatment BW : SL (g mm)1)

Initial 0.108 ± 0.001a

Laminaria digitata 0.155 ± 0.001b

Diet A (DW 2%KX; 1 : 3) 0.109 ± 0.002ac

Diet B (SW 2%KX; 1 : 3) 0.114 ± 0.004cd

Diet C (SW 2%KX; 1 : 1) 0.119 ± 0.007d

Diet D (SW 1.5%KX; 1 : 1) 0.115 ± 0.001d


seawater.

Letters indicate the results of the Kruskal–Wallis multiple compar-

ison post hoc test. The values in the same column that do not have

the same superscript parameters were significantly different from

each other (P < 0.05).

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


feeding behaviour, and therefore abalone require that artifi-

cial feeds retain structural integrity in SW for at least 2 days

(Fleming et al. 1996). However, several studies report short

experimental periods of feed presentation ranging from 12 h

(Rivero & Viana 1996; Garcia-Esquivel et al. 2007) to 16 h

(Sales & Britz 2002a; b), whilst others report longer intervals

(3 days) between feeding to satiation (Mai 1998), and

therefore comparisons with this study are difficult to inter-

pret.

Previous studies have reported that blending and fine-

sieving of feed ingredients to <450 lm had a significant

influence on dry matter leaching of formulated feeds with

improved diet performance, measured as apparent digest-

ibility coefficients, for abalone diets produced within this

particle size category (Sales & Britz 2002b). By contrast,

however, Obaldo et al. (1999) reported poorer diet perfor-

mance for shrimp feeds at particle sizes <100 lm. Further

investigation to determine the optimal production method for

the novel KX feeds and factors that influence the property of

this binder for reduced dry matter leaching is required.

In this study, KX binder configuration did not significantly

affect diet performance on any parameter assessed. However,

the SGR achieved by the control treatment, L. digitata,

exceeded KX artificial diet performance in this parameter,

and overall, L. digitata had significantly higher FCE values

than all KX diet treatments.

Feed consumption rates in this study showed no significant

variability between all the experimental treatments. Although

non-significant, trends showed that the lowest DFC was

observed in the L. digitata treatment. The similarity of the

feeding rate, as measured by DFC, across all experimental

feed treatments suggests that feeding rate of H. discus hannai

for the feed treatments in this study was relatively constant

given the current feed formulations and experimental con-

ditions. Abalone feed by repeated rasping action of the

radula, and it is likely that the relatively soft texture of fully

hydrated KX feeds influenced feeding rates. As a result,

comparable daily feed consumption rates for the KX feeds

and L. digitata were achieved despite the abalone having

been predisposed to L. digitata. Previous studies have related

consumption in H. rubra to physical (e.g. toughness) and

chemical (e.g. presence of phlorotannins) feed characteristics

rather than nutritional quality (Fleming 1995), and indeed

the South African abalone, H. midae, has been found to

select for softer textured red and green macroalgae over kelp

species in feed preference experiments (Day & Cook 1995). In

Ireland, anecdotal evidence from producers pertaining to the

development of H. discus hannai culture have indicated that

the ecologically abundant species of kelp, Laminaria hyper-

borea, was unsuitable for culture of H. discus hannai

purported to result from the tougher texture of this algal

species (Hession et al. 1998).

Consumption rates in culture studies of H. discus hannai is

not a well-documented experimental parameter. Numerous

foundation studies on this species (for example: Mai et al.

1994, 1995a,b, 1996; Mai 1998; Tan et al. 2002a,b; Park et al.

2008) have measured food conversion ratio (FCR), growth,

survival and compositional tissue analyses as indicator of

the dietary requirements of the species. Mai et al. (1995b)

describes consumption in abalone as a very difficult para-

meter to evaluate in relation to artificial feeds because of the

highly particulate nature of the feed ingredients and the

feeding mechanism of the abalone. In essence, there is no

quantitative evaluation of ingestion as a result of the rasping

action of the radula, and there is no reason to assume that all

feed particles removed as a result of the feeding action are

consumed by the individual. In field studies, the proportion

of food consumed in abalone (Haliotis sp.) has been found

to be an indicator of feed palatability in situations where

the environmental availability allows access to more than

one feed type (Tutschulte & Connell 1988). Mercer et al.

(1993) found that feeding rates of H. discus hannai

(0.1–0.4% BW day)1) on six species of algae (Alaria escul-

enta, L. digitata, L. saccharina, Ulva lactuca, Palmaria

palmata and Chrondris crispus) and two mixed feeds levelled

off after 10 weeks, indicating a habitual acclimation to the

feed, and subsequent analyses of feeding rates were not

conducted in their study. When compared with Mercer et al.

(1993), the feeding rates of this study indicate comparatively

low feeding rates for H. discus hannai (0.5–0.8% BW day)1)

on all feed treatments. Our evaluation of consumption

throughout this study did not show any evidence of habitual

acclimation to the experimental feeds, and further study of

this aspect of abalone feeding behaviour may be necessary to

maximize feeding potential for experimental feeds. The

plastic responses of abalone to varied feed types (Garcia-

Esquivel & Felbeck 2008) coupled with adaptive physiolog-

ical processes suggests that, given time, abalone will consume

a range of feeds, and longer feeding trials would provide an

indication of adaptive feed responses.

The significantly higher FCE of the L. digitata treatment

in this study over all experimental KX feed treatments indi-

cated that the nutrient utilization of H. discus hannai for

fresh L. digitata was better than the KX feed formulation

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


ingredients. The proximal composition analyses, outlined in

Table 2, indicated notable differences in protein, carbohy-

drate and lipid concentrations between the natural and

experimental feed types. The success of a formulated feed

type may be dependent on a series of factors including feed

digestibility, gut physiology, gut transition times and inter-

active effects of nutrient composition that were not evaluated

in this study. The efficiency with which dry matter feed was

converted to wet weight gain despite comparable consump-

tion of L. digitata with the KX feeds may suggest an adaptive

response to this feed type. Haliotis discus hannai have asso-

ciative gut microflora for particular feed types, and the

composition of the gut microflora has been shown to change

over time and with changes in feed (Tanaka et al. 2003). In

addition, a 6- month experiment conducted by Garcia-

Esquivel & Felbeck (2006) found that digestive enzyme

activity in various parts of the gut of Haliotis rufescens al-

tered according to feed type.

It is suggested that the significantly higher FCE of

L. digitata in this study could have been as a result of a

history of feeding on L. digitata as this was the feed used at

the commercial hatchery from which the experimental

H. discus hannai were obtained. It is likely that the experi-

mental abalone were adapted to L. digitata as a feed type

through acquired optimal gut digestion and nutrient utiliza-

tion. It is therefore recommended that an adaptive period

should be allocated prior to growth assessment of artificial

feeds to remove any bias associated with previous feeding

history on growth assessment results (Pereira et al. 2007).

There are variable reports of acclimation periods for abalone

prior to experimental evaluation of formulated feeds in the

literature (Table 7). Further study is needed to determine the

optimal duration of acclimation period for experimental feed

types.

Although no significant differences in the LGR between

treatments were evident in this study, the SGR indicated

that a higher SGR was observed in the L. digitata treat-

ment. Haliotis discus hannai are slow growers achieving

approximately 1–2 cm growth in SL per year (Lee 2004).

Assuming linear growth, the LGR in this study of the

L. digitata treatment (0.058 ± 0.02 mm SL day)1) would

approximate to the maximum growth projected by Lee

(2004) in one year (2.1 cm year)1), and given that this

treatment was our experimental control, we evaluate the

growth achieved on the L. digitata treatment as a indication

that the experimental parameters were sufficient to promote

growth of H. discus hannai within the published range for

this species. Growth in the experimental KX feed treatments

in this study was below the projected annual growth range

for H. discus hannai as reported by Lee (2004) and lower

than published growth rate for this species in experimental

studies (Table 8).

BW/SL ratio is a useful determinant of profitability in a

commercial species such as abalone (Naidoo et al. 2006),

where the final market product is the whole animal tissue

weight. Moreover, the BW/SL ratio gives an indication of the

level of �fattening� achieved by on-growing feeds and as such

is a useful tool to collate the combined length and weight

achievements of a feed into a discernable parameter that

reflects commercial considerations. A commercially accept-

able feed will ideally achieve high BW/SL ratios more so than

extreme growth in either biometric dimension (e.g. length

and weight).

The BW/SL ratio in this study showed that the highest

BW/SL ratio was achieved on the L. digitata treatment

(0.155 ± 0.001 g mm)1). This was a significantly higher BW/

SL ratio than that of the initial sample (0.108 ±

0.001 g mm)1) and was also significantly higher than the

Table 7 Acclimation periods allocated

prior to abalone growth trialsReference Species Interim feed type

Acclimation

period

Britz (1996b) Haliotis midae Plocamium corallorhiza 3 months

Guzman & Viana (1998) Haliotis fulgens Artificial feed (abalone viscera

silage, fish meal &

soybean meal)

75 days

Coote et al. (2000) Haliotis laevigata Experimental study feeds 22 days

Shipton & Britz (2001) H. midae Fish meal artificial feed 1 month

Sales et al. (2003) H. midae Artificial feed–reared abalone 16 months

Macey & Coyne (2005) H. midae Basal artificial feed 3 weeks

Garcia-Esquivel et al.

(2007)

H. fulgens No interim feed mentioned 2 weeks

Zhang et al. (2008) Haliotis discus

hannai

Basal artificial feed 1 week

This study H. discus hannai Laminaria digitata 2 weeks

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


BW/SL ratio of all experimental KX feed treatments at the

end of the study. The BW/SL ratio of Diet A was not sig-

nificantly different to the initial BW/SL ratio, and this was

the only experimental KX diet that showed no significant

increase in BW/SL ratio over the duration of the growth trial.

Although differences between KX feeds were non-significant,

trends showed that Diet C (0.119 ± 0.01 g mm)1) was the

best performing experimental KX diet in terms of the

BW/SL ratio increase of all novel feeds.

Survival in all treatments in this study was high and

L. digitata promoted maximum survival (100%) in this

study. The overall high survival rate (>91%) in all treatments

in this study may be an indication of the general suitability of

the KX feeds for abalone culture.

High survival rates have been reported forH. discus hannai

in previous studies (Table 9). The high percentage survival in

this study may also be linked to the husbandry protocols

maintained throughout the experimental period. Abalone

culturing success has been linked to a number of experi-

mental parameters including handling stress (Sales & Britz

2001), light intensity (Hahn 1989; Kim et al. 1997), water

quality (FAO, UNDP & Shallow Seafarming Institute 1990),

tank design and nutrition (Searle et al. 2006) and water

temperature (Britz et al. 1997). Frequent tank cleaning at

each feeding interval has also been attributed to survival

success with H. discus hannai (Mai et al. 1995b). Haliotis

discus hannai in this study were cultured within the recom-

mended ranges for this species (FAO, UNDP & Shallow

Seafarming Institute 1990) with the exception of water tem-

perature, which was maintained below the range outlined in

FAO, UNDP & Shallow Seafarming Institute (1990) but

above water temperature targets of previous studies (Mai

et al. 1995b; Park et al. 2008). The experimental system

utilized for this study entailed minimum handling of abalone

that were maintained in darkness during the growth trial.

Garcia-Esquivel et al. (2007) have demonstrated thatHaliotis

fulgens can be best cultured at 20 �C and 00 : 24 or 12 : 12

light : dark regimes.

Table 8 Comparative growth perfor-

mance of Haliotis discus hannai in

experimental growth trialsReference Feed type

Study

duration

(days)

Growth

(length)

(lm day)1)

Weight

gain

(% day)1)

Mai (1998) Artificial feed 100 – 0.74–0.88

Mai et al. (2001) Artificial feed 112 66.4–76.0 1.27–1.34

Tan & Mai (2001a) Artificial feed 120 38.66–59.60 0.39–0.49

Tan & Mai (2001b) Artificial feed 112 62.3–86.6 0.48–1.22

Tan et al. (2001) Artificial feed 112 67.4–86.9 0.76–1.24

Tan et al. (2002b) Artificial feed 112 36.87–55.07 0.37–0.58

Park et al. (2008)1 Undaria pinnatifida

Laminaria japonica

180 100.0 1.35

This study Laminaria digitata

KX feeds

84 58.0

22.0–26.0

0.56

0.14–0.23

KX, konjac glucomannan–xanthan gum.1 Commercial-scale experimental study.

Table 9 Mean survival rates (%) of Haliotis discus hannai in previous and the current on-growing studies

Reference

Study

duration

(days)

Length

(mm)

Weight

(g)

Stocking

parameters

(individuals tank)1)

Tank

volume

(cm3)

Survival

(%)

Mercer et al. (1993) 365 19.3 ± 0.10 0.817 ± 0.03 25 5301 84.0–95.0

Mai et al. (1995a) 100 0.389 20 10 000 87.5–98.3

Mai et al. (1995b) 100 – 0.378 ± 0.02 25 10 000 92.0–98.7

Mai (1998) 100 – 0.23 ± 0.01 30 10 000 86.7–96.7

Mai & Tan (2000) 112 16.11 ± 0.10 0.702 ± 0.02 25 8000 88.0–100.0

Mai et al. (2001) 112 10.92 ± 0.10 0.145 ± 0.001 40 19 600 85.8–94.2

Tan et al. (2001) 112 15.45 ± 0.03 0.62 ± 0.02 25 8000 94.7–100.0

Tan & Mai (2001a) 120 18.65 ± 0.18 1.18 ± 0.04 30 8000 75.0–83.3

Tan & Mai (2001b) 112 16.41 ± 0.04 0.74 ± 0.01 25 8000 94.7–100.0

Park et al. (2008)1 180 24.5 2.2 1667 192 · 104 94.5

This Study 84 25.89 ± 0.18 2.79 ± 0.06 15 8400 91.1–100.0

1 Commercial-scale experimental study.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


The aim of this study was to determine the most appropriate

feed binder for further KX feed development for juvenile

H. discus hannai. Based on the overall lack of a significant

difference between KX treatments in this study, further diet

development was based on the trends observed between

treatments. In terms of FCE, SGR, BW/SL ratio and sur-

vival, trends showed that the use of DW did not positively

benefit KX feed performance. There are subtle, although

non-significant, indications that a reduced K : X ratio was

beneficial to overall feed performance.

Based on the results of this study, further feed develop-

ment for abalone was conducted using the binder configu-

ration of Diet C (SW 2% KX; 1 : 1). Overall, the results of

this study indicated that feed and growth performance of

juvenile H. discus hannai was better with feeding fresh

L. digitata, and therefore an optimized diet formulation will

be utilized in the next phase of KX diet development for

juvenile H. discus hannai (O�Mahoney 2009).

The observed ability of the KX-produced feeds to retain

structural integrity in SW is an indication of the potential for

this binder in aquatic feed production where water quality

issues are paramount. Despite the good growth rates that

may be achieved with some existing commercially available

abalone feeds, we have observed that such feeds can create

severe problems with water quality maintenance. Such

aspects negate the positive benefit of these existing feeds for

commercial use. An all-encompassing sustainable feed

development programme requires consideration of the envi-

ronmental impact of the aquatic feeds in conjunction with

the input resources.

This study was conducted at the Aquaculture & Fisheries

Development Centre (AFDC), University College Cork. This

research was funded by Enterprise Ireland Commercializa-

tion Fund 2007–2008. The authors thank Chris O�Grady of

Brandon Bay Seafood�s Ltd for the supply of abalone.

Thanks also to the staff of the AFDC for technical assistance.

Thanks to Prof. Ed. Morris for comments on the manuscript

and also to the reviewers for insightful contributions. This

study is dedicated to James O�Mahoney.

Alvarez-Mancenido, F., Landin, M. & Martınez-Pacheco, R. (2008)

Konjac glucomannan/xanthan gum enzyme sensitive binary mix-

tures for colonic drug delivery. Eur. J. Pharm. Biopharm., 69, 573–

581.

Britz, P.J. (1996a) Effect of dietary protein level on growth perfor-

mance of South African abalone, Halitois midae, fed fishmeal-base

semi-purified diets. Aquaculture, 140, 55–61.

Britz, P.J. (1996b) The suitability of selected protein sources for

inclusion in formulated diets for the South African abalone,

Haliotis midae. Aquaculture, 140, 63–73.

Britz, P.J., Hecht, T. & Mangold, S. (1997) Effect of temperature on

growth, feed consumption and nutritional indices ofHaliotis midae

fed a formulated diet. Aquaculture, 152, 191–203.

Caltagirone, A., Francour, P. & Fernandez, C. (1992) Formulation

of an artificial diet for the rearing of the urchin Paracentrotus

lividus: I. Comparison of different binding agents. In: Echinoderm

Research (Scalera-Liaci, L. et al. eds.), pp. 115–119. A.A. Balk-

ema, Rotterdam.

Coote, T.A., Hone, P.W., Kenyon, R. & Maguire, G.B. (1996) The

effect of different combinations of dietary calcium and phospho-

rous on the growth of juvenile Haliotis laevigata. Aquaculture, 145,

267–279.

Coote, T.A., Hone, P.W., Van Barneveld, R.J. & Maguire, G.B.

(2000) Optimal protein level in a semipurified diet for juvenile

greenlip abalone Haliotis laevigata. Aquac. Nutr., 6, 213–220.

Day, R.W. & Cook, P. (1995) Bias towards brown algae in deter-

mining diet and food preferences: the South African abalone

Haliotis midae. Mar. Freshw. Res., 46, 623–627.

De Muylder, E., Hage, H. & van der Velden, G. (2008) Binders:

gelatin as alternative for urea formaldehyde and wheat gluten in

the production of water stable shrimp feeds. Aquafeed Int., 11,

10–13.

Dea, I.C.M. (1993) Conformational origins of polysaccharide solu-

tion and gel properties. In: Industrial Gums (Whistler, R.L. &

BeMiller, J.N. eds.), pp. 21–52. Academic Press, London.

Eyo-okon, I.E. & Hilton, C.S. (2003) Use of Glucomannan Hydro-

colloid as Filler Material in Prostheses. Konjac Technologies, LLC,

South River, NJ. United States Patent 6537318.

Fagbenro, O. & Jauncey, K. (1995) Water stability, nutrient leaching

and nutritional properties of moist fermented fish silage diets.

Aquac. Eng., 14, 143–153.

Fan, J., Wang, K., Liu, M. & He, Z. (2008) In vitro evaluations of

konjac glucomannan and xanthan gum mixture as the sustained

release material of matrix tablet. Carbohydr. Polym., 73, 241–247.

FAO (2009) Fishery and Aquaculture Statistics 1950–2007. FAO,

Rome. http://www.fao.org/fishery/statistics/en. last accessed on

September 5, 2009).

FAO, UNDP & Shallow Seafarming Institute (1990) Training man-

ual on artificial breeding of abalone (Haliotis discus hannai) in

Korea D.P.R. In FAO/UNDP Regional Seafarming Development

and Demonstration Project, RAS/90/002, pp. 107. TrainingManual,

No. 7. FAO, UNDP & Shallow Seafarming Institute, Bangkok.

Fermin, A.C. (2003) Effects of alternate starvation and refeeding

cycles on food consumption and compensatory growth of abalone,

Haliotis asinina (Linnaeus). Aquac. Res., 33, 197–202.

Fleming, A.E. (1995) Growth, intake, feed conversion efficiency and

chemosensory preference of the Australian abalone,Haliotis rubra.

Aquaculture, 132, 297–311.

Fleming, A.E., Van Barneveld, R.J. & Hone, P.W. (1996) The

development of artificial diets for abalone: a review and future

directions. Aquaculture, 140, 5–53.

Garcia-Esquivel, Z. & Felbeck, H. (2006) Activity of digestive

enzymes along the gut of juvenile red abalone, Haliotis rufescens,

fed natural and balanced diets. Aquaculture, 261, 615–625.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Garcia-Esquivel, Z. & Felbeck, H. (2008) Comparative performance

of juvenile red abalone, Haliotis rufescens, reared in laboratory

with fresh kelp and balanced diets. Aquac. Nutr., 15, 209–217.

Garcia-Esquivel, Z., Montes-Magallon, S. & Gonzalez-Gomez,

M.A. (2007) Effect of temperature and photoperiod on the growth,

feed consumption, and biochemical content of juvenile green

abalone, Haliotis fulgens, fed on a balanced diet. Aquaculture, 262,

129–141.

Gorfine, H.K. (1991) An Artificial Diet for Hatchery-reared Abalone

Haliotis rubra. Marine Science Laboratories, International Report

No. 190, Queenscliff, Australia.

Goycoolea, F.M., Richardson, R.K., Morris, E.R. & Gidley, M.J.

(1995) Stoichiometry and conformation of xanthan in synergistic

gelation with locust bean gum or konjac glucomannan. Macro-

molecules, 28, 8308–8320.

Guzman, J.M. & Viana, M.T. (1998) Growth of abalone Haliotis

fulgens fed diets with and without fish meal, compared to a com-

mercial diet. Aquaculture, 165, 321–331.

Hahn, K.O. (1989) Handbook of Culture of Abalone and Other

Marine Gastropods, pp. 368. CRC Press, FL.

Harada, K., Miyasaki, T., Kawashima, S. & Shiota, H. (1996)

Studies on the feeding attractants for fishes and shellfishes. XXVI.

Probable feeding attractants in allspice Pimenta officinalis for

black abalone Haliotis discus. Aquaculture, 140, 99–108.

Hession, C., Guiry, M.D., McGarvey, S. & Joyce, J. (1998) Mapping

and Assessment of the Seaweed Resources (Ascophyllum nodosum,

Laminaria spp.) off the West Coast of Ireland, pp. 1–89. Marine

Resource Series, No. 5, Marine Institute, Galway, Ireland.

Kato, K. & Matsuda, K. (1969) Studies on the chemical structure of

konjac mannan. Part I. Isolation and characterization of oligo-

saccharides from the partial acid hydrolyzate of mannan. Agric.

Biol. Chem., 33, 1446–1453.

Kelco (2007) Keltrol/Kelzan Xanthan Gum Book, pp. 32. CP Kelco,

Atlanta, GA.

Kelly, E. ed. (2005) The Role of Kelp in the Marine Environment. Irish

Wildlife Manuals No. 17, National Parks and Wildlife Service,

Department of Environment, Heritage and Local Government,

Dublin, Ireland.

Kim, B.L., Kim, J.W., Wom, S.H., Wi, C.H. & Park, H.Y. (1997)

Effects of complete dark conditions on the growth of four

species of juvenile abalones. Bull. Nat. Fish. Dev. Res. Inst., 53,

103–110.

Knauer, J., Britz, P.J. & Hecht, T. (1993) The effect of seven binding

agents on 24-hour water stability of an artificial weaning diet for

the South African abalone, Haliotis midae (Haliotidae, Gastro-

poda). Aquaculture, 115, 237–334.

Lee, S.-M. (2004) Utilization of dietary protein, lipid, and carbo-

hydrate by abalone Haliotis discus hannai: a review. J. Shellfish

Res., 23, 1027–1030.

Liu, F., Ai, Q., Mai, K., Tan, B., Ma, H., Xu, W., Zhang, W. &

LiuFu, Z. (2008) Effects of Dietary Binders on Survival and

Growth Performance of Postlarval Tongue Sole, Cynoglossus

semilaevis (Gunther). J. World Aquac. Soc., 39, 500–509.

Macey, B.M. & Coyne, V.E. (2005) Improved growth rate and

disease resistance in farmed Haliotis midae through probiotic

treatment. Aquaculture, 245, 249–261.

Mai, K. (1998) Comparative studies on the nutrition of two species

of abalone, Haliotis tuberculata L. and H. discus hannai Ino. VII.

Effects of dietary vitamin C on survival, growth and tissue con-

centration of ascorbic acid. Aquaculture, 161, 383–392.

Mai, K. & Tan, B. (2000) Iron methionine (FeMet) and iron sulfate

(FeSO4) as sources of dietary iron for juvenile abalone, Haliotis

discus hannai. J. Shellfish Res., 19, 861–868.

Mai, K., Mercer, J.P. & Donlon, J. (1994) Comparative studies on

the nutrition of two species of abalone, Haliotis tuberculata L. and

H. discus hannai Ino. II. Amino acid composition of abalone and

six species of macroalgae with an assessment of their nutritional

value. Aquaculture, 128, 115–130.

Mai, K., Mercer, J.P. & Donlon, J. (1995a) Comparative studies on


H. discus hannai Ino. Aquaculture, 134, 65–80.

Mai, K., Mercer, J.P. & Donlon, J. (1995b) Comparative studies on


H. discus hannai Ino. IV. Optimum dietary protein level for

growth. Aquaculture, 136, 165–180.

Mai, K., Mercer, J.P. & Donlon, J. (1996) Comparative studies on


H. discus hannai Ino. V. The role of polyunsaturated fatty acids of

macroalgae in abalone nutrition. Aquaculture, 139, 77–89.

Mai, K., Wu, G. & Zhu, W. (2001) Abalone, Haliotis discus hannai

Ino, can synthesis myo-inositol de novo to meet physiological

needs. J. Nutr., 131, 2898–2903.

Melton, L.D., Mindt, L. & Rees, D.A. (1976) Covalent structure of

the extracellular polysaccharide from Xanthomonas campestris:

evidence from partial hydrolysis studies. Carbohydr. Res., 46, 245–

257.

Mercer, J.P., Mai, K. & Donlon, J. (1993) Comparative studies on


H. discus hannai Ino. I. Effects of algal diet on growth and bio-

chemical composition. Invertebr. Reprod. Dev., 23, 75–88.

Morris, E.R., Rees, D.A., Young, G., Walkinshaw, M.D. & Darke,

A. (1977) Order-disorder transition for a bacterial polysaccharide

in solution. A role for polysaccharide conformation in recognition

between Xanthomonas pathogen and its plant host. J. Mol. Biol.,

110, 1–16.

Mortensen, A., Siikavuopio, S.I. & Raa, J. (2003) Use of transglu-

taminase to produce a stable sea urchin feed. In: Sea Urchin

Fisheries and Ecology (Lawrence, J.M. & Guzman, O. eds.),

pp. 203–213. Destech Publications Inc., Puerto Varas, Chile.

Naidoo, K., Maneveldt, G., Ruck, K. & Bolton, J.J. (2006) A

comparison of various seaweed-based diets and formulated feed on

growth rate of abalone in a land-based aquaculture system.

J. Appl. Phycol., 18, 437–443.

Obaldo, L.G., Dominy, W.G., Terpstra, J.H., Cody, J.J. & Behnke,

K.C. (1999) The impact of ingredient particle size on shrimp feed.

J. Appl. Aquac., 8, 55–67.

O�Mahoney, M. (2009) Development of a Novel Binder for Aquacul-

ture: application of a Konjac glucomannan-xanthan Gum Binder to

Formulated Feed Development for the Sea Urchin Paracentrotus

lividus and abalone Haliotis discus hannai, pp. 297. PhD Thesis,

National University of Ireland, Cork.

Palma, J., Bureau, D.P. & Andrade, J.P. (2008) Effects of binder type

and binder addition on the growth of juvenile Palaemonetes vari-

ans and Palaemon elegans (Crustacea: Palaemonidae). Aquac. Int.,

16, 427–436.

Park, J., Kim, P.-K. & Jo, J.-Y. (2008) Growth performance of disk

abalone Haliotis discus hannai in pilot- and commercial-scale

recirculating aquaculture systems. Aquac. Int., 16, 191–202.

Pearce, C.M., Daggett, T.L. & Robinson, S.M.C. (2002) Effect of

binder type and concentration on prepared feed stability and

gonad yield and quality of the green sea urchin, Strongylocentrotus

droebachiensis. Aquaculture, 205, 301–323.

Pereira, L., Riquelme, T. & Hosokawa, H. (2007) Effect of three

photoperiod regimes on the growth and mortality of the Japa-

nese abalone Haliotis discus hannai Ino. J. Shellfish Res., 26,

763–767.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


Rivero, L.E. & Viana, M.T. (1996) Effect of pH, water stability and

toughness of artificial diets on the palatability for juvenile abalone

Haliotis fulgens. Aquaculture, 144, 353–362.

Ruscoe, I.M., Jones, C.M., Jones, P.L. & Caley, P. (2005) The

effects of various binders and moisture content on pellet stability

of research diets for freshwater crayfish. Aquac. Nutr., 11,

87–93.

Sales, J. & Britz, P.J. (2001) Research on abalone (Halitois midae L.)

cultivation in South Africa. Aquac. Res., 32, 863–874.

Sales, J. & Britz, P.J. (2002a) Evaluation of the reference diet sub-

stitution method for determination of apparent nutrient digest-

ibility coefficients of feed ingredients for South African abalone

(Haliotis midae L.). Aquaculture, 207, 113–123.

Sales, J. & Britz, P.J. (2002b) Influence of ingredient particle size and

inclusion level of pre-gelatinised maize starch on apparent digest-

ibility coefficients of diets in South African abalone (Haliotis midae

L.). Aquaculture, 212, 299–309.

Sales, J., Truter, P.J. & Britz, P.J. (2003) Optimum dietary crude

protein level for growth in South African abalone (Haliotis midae

L.). Aquac. Nutr., 9, 85–89.

Searle, T., Roberts, R.D. & Lokman, P.M. (2006) Effects of tem-

perature on growth of juvenile blackfoot abalone, Haliotis iris

Gmelin. Aquac. Res., 37, 1441–1449.

Shipton, T.A. & Britz, P.J. (2001) The effect of animal size on the

ability of Haliotis midae L. to utilise selected dietary protein

sources. Aquac. Res., 32, 393–403.

Storebakken, T. & Austreng, E. (1987) Binders in fish feeds. II: effect

of different alginates on the digestibility of macronutrients in

rainbow trout. Aquaculture, 60, 121–131.

Tan, B. & Mai, K. (2001a) Effect of dietary vitamin K on survival,

growth and tissue concentrations of phylloquinone (PK) and

menaquinone-4 (MK-4) for juvenile abalone, Haliotis discus

hannai Ino. J. Exp. Mar. Biol. Ecol., 256, 229–239.

Tan, B. & Mai, K. (2001b) Zinc methionine and zinc sulfate as

sources of dietary zinc for juvenile abalone, Haliotis discus hannai

Ino. Aquaculture, 192, 67–84.

Tan, B., Mai, K. & Liufu, Z. (2001) Response of juvenile abalone,

Haliotis discus hannai, to dietary calcium, phosphorous and

calcium/phosphorous ratio. Aquaculture, 198, 141–158.

Tan, B., Mai, K. & Liufu, Z. (2002a) Dietary phosphorous

requirement of juvenile abalone, H. discus hannai Ino. Chin. J.

Oceanol. Limnol., 20, 22–31.

Tan, B., Mai, K. & Xu, W. (2002b) Availability of phosphorous

from selected inorganic phosphates to juvenile abalone, Haliotis

discus hannai Ino. Chin. J. Oceanol. Limnol., 20, 118–128.

Tanaka, R., Sugimura, I., Sawabe, T., Yoshimizu, M. & Ezura, Y.

(2003) Gut microflora of abalone Haliotis discus hannai in culture

changes coincident with a change in diet. Fish. Sci., 69, 951–958.

Troell, M., Robertson-Andersson, D., Anderson, R.J., Bolton, J.J.,

Maneveldt, G., Halling, C. & Probyn, T. (2006) Abalone farming

in South Africa: an overview with perspectives on kelp resources,

abalone feed, potential for on-farm seaweed production and socio-

economic importance. Aquaculture, 257, 266–281.

Tutschulte, T.C. & Connell, J.H. (1988) Feeding behavior and algal

food of three species of abalones (Haliotis) in southern California.

Mar. Ecol. Prog. Ser., 49, 57–64.

Uki, N., Kemuyama, A. & Watanabe, T. (1985) Development of

semipurified test diets for abalone. Bull. Japanese Soc. Sci. Fish.,

15, 1825–1833.

Werner, A. & Kraan, S. (2004) Review of the Potential Mechanisation

of Kelp Harvesting in Ireland. Marine Environment and Health

Series, No. 17, pp. 52. Marine Institute, Galway, Ireland.

Zhang, W., Mai, K., Xu, W., Liufu, Z., Tan, B., Ai, Q., Ma, H. &

Wang, X. (2008) Effects of dietary guaiacol on shell biomineral-

ization of juvenile abaloneHaliotis discus hannai, Ino. Aquac. Res.,

39, 954–961.

. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .


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