Chapter 3

Water hyacinth as alternative feed

Pergaps the most realistic use of water hyacinth right at this moment is its use as alternative feed.

Because –

1. Its high protein content

2. Its availability

3. Its low cost

Water hyacinth can be used as feed in three forms – fresh, ensiled and wilted. To reduce its high

fiber content, fermentation is used in some cases.

What is ensiled form ?

In ensiled form, grass or any other green fodder is stored in silo, in airtight condition. Drying is

not used for silage. Ensiled cops are used for animal feed in winter.

What is wilted form ?

Wilted crops are partially air dried crops. Wilting is done before ensiling.

There are many reports made throughout the world suggesting WH as a very good alternative

animal feed. Some of its are mentioned here.

For ruminants

There is no doubt that the cellulose content of water hyacinth can be used as a good source of

energy for ruminants (Mukherjee & Nandi, 2004). Para grass (Brachiaria mutica) has been

replaced with fresh WH in their cattle (Biswas & Mandal, 1988). Fresh WH performed better

than wilted WH for goat (Aregheore & Cawa, 2000). If WH is mixed with a rice straw based

diet, growth of beef cattle increased (Islam et al., 2009). Addition of 30% dried WH in basal diet

of wheat straw resulted in 500g daily live weight gain (Parashar et al., 1999). Wilting reduces

silage losses, it is important as WH contains low dry matter content (McDonald et al., 2011).

Ensiled WH was mixed with rice straw, urea and molasses. Upon feeding it to dairy cattle, it

resulted in better milk yield (Chakraborty et al., 1991). Sheep accepts both ensiled and wilted

WH (Abou-Raya et al., 1980; Baldwin et al., 1975). Although wilted WH cannot be used as feed

for sheep solely, it can be used upto 50% in their feed (Abdelhamid & Gabr, 1991). After

extracting mechanically its juice, WH can be used as feed for buffalo calves (Borhami et al.,

1992).

Pigs

In Vietnam, cooked or fresh WH reduced organic matter digestibility. But it did not affect feed

intake and concentrate usage was reduced upto 6% (Manh et al., 2002b; Son & Trung, 2002).

Ensiled WH costs low, so it suits small holder farms.

Rabbits

WH that was grown in waste water replaced alfalfa successfully in rabbit diet (Moreland et al.,

1991). Para grass was replaced upto 60% with WH and it resulted in better growth performance

(Thu & Dong, 2009).

Ducks

In the Mekong Delta of Vietnam, birds are fed with conventional diets but alternative feed like

WH and duckweed are provided to duck. (Sotolu, 2010; Men et al., 2002). Men and Yamasaki

(2005) found the

replacement upto 25% of a commercial diet by fresh WH to be economically profitable due to

the lower feed cost, but poor in performance. In China, WH has been successfully used as duck

feed. Replacement of traditional diet with WH results in higher daily feed intake, egg laying ratio

and egg quality (Jianbo et al., 2008).

Fish

WH can be a good feed source if its high fiber content can be reduced in any way. It is

recommended by Hertrampf & Piedad-Pascual for fresh water fish (Hertrampf & Piedad-

Pascual,2000). On the other hand, for tilapia feed it may not perform well as suggested by

Buddington due to high fiber content (Buddington, 1980). El-Sayed (2003) found that ensiled

WH showed better performance than fresh WH replacing wheat bran in diet upto 20% .The

supplementation of basal diet with WH can be as high as 50% for fish (Hertrampf & Piedad-

Pascual, 2000).

Water hyacinth as fish feed

Study for African catfish

Rapid growth rate of water hyacinth affects water chemistry in many ways.it reduces light

penetrationand dissolved oygen level in water, affects flora and fauna,increases rate of water loss

due to evaporanspiration. To make its practical use, it s being considered as alternative plant

protein source in livestock feed.

Water hyacinth contains high amount of cell wall material which is mainly cellulose and also a

high amount of amino acid. Fiber content is higher in whole water hyacinth plant than in leaves

only. Clarias gariepinus is a very common african catfish. To compare the digestibility of water

hyacinth plant as fish meal, following study was made.

Experimental work

Collection and processing of water hyacinth

Fresh water hyacinth plants were collected from Awba dam of university of Ibadan. They were

solar dried for 2 weeks. Leaves were ground to make WLM (water hyacinth leaves meal) and the

whole plant were ground to make WPM (water hyacinth plant meal). These two meals have

differences in composition. WLM has higher crude protein than WPM whereas WPM has higher

ash than WLM.

Table 3.1: proximate composition of WHMs

WHM CP (%) CL (%) C Fiber (%) ash (%) NFE (%)

WPM 24.17 2.37 19.62 11.35 42.49

WLM 28.2 4.7 14.79 7.03 45.28

How experimental diets were made

Three isoproteic (40% CP) diets were prepared, the main diet being WPM, WLM and SBM

(soya bean meal) respectively. SBM acted like control. There were other components that make

up the complete diet like fishmeal, groundnut cake, bone meal etc. Allowance was made to

accommodate 1% chromic oxide in each of three diets that served as marker.

Table 3.2: gross composition of experimental diets (g/100/DM)

Ingredients Diet 1 Diet 2 Diet 3

Fish meal 18.94 18.94 18.94

Groundnut cake 26.97 26.97 26.97

SBM 22.91

WPM 26.72

WLM 31.63

Yellow maize 25.18 21.37 16.46

Bone meal 1 1 1

Vit premix 2.5 2.5 2.5

Fish oil 1.5 1.5 1.5

Chromic oxide 1 1 1

Table 3.3: proximate composition of experimental diets (g/100/DM)

Parameter Diet 1 Diet 2 Diet 3

Crude protein 40.13 40.08 40.11

Fiber 4.38 6.47 5.51

Fat 7.14 4.21 4.86

Ash 4.62 6.11 6.3

NFE 43.73 43.13 43.22

Gross energy

(kcal/g/DM)

328.16 326.32 329.25

Digestibility study

90 catfish fingerlings of11.2 gram average weight were randomly distributed into 9 concrete

tanks of with 150 L capacity. Water supply source was deep well, flowrate of 2 L/min for 70

days. Dissolved oxygen, pH, ammonia – these parameters were taken using a combined digital

meter (YSI). Fish were fed twice (8:00, 18:00 hrs).

Faeces were collected from each tank before feeding and 8 hrs after feeding. Faeces were oven

dried at 48 degree celsius for 120 hrs. All meals, diets, fish samples and faecal wastes were

chemically analyzed for their proximate composition according to AOAC method. At the end of

the experiment, survival rates were determined.

Determination of growth, nutrient utilization and digestibility coefficient.

Following growth and nutrient utiization parameters were determined according to Aderlu et.al.

1. Mean weight gain (MWG)= (W2-W1)%

2. Specific growth rate (SGR) =(LogW2-LogW1)/(T2-T1)

W2=final weight of fish (gm)

W1=initial weight of fish(gm)

T2= end of experiment (days)

T1=beginning of experiment (days)

3. Protein efficiency ratio (PER)= weight gain (gm)/ protein intake (gm)

4. Feed conversion ratio (FCR)= Total feed intake/ weight gain(gm)

5. Protein intake= feed fed x crude protein of the feed

6. Nitrogen metabolism (Nm) = 0.549 x(a+b)xh/2

a= initial mean weight of fish (gm)

b= final mean weight of fish (gm)

h= experimental period (days)

7. Apparent digestibilty coefficient (ADC) = 102 – (102 x (1d/1f) x (Nf/Nd))

Nd=protein in diet

Nf=protein in faecs

1d=% Cr2O3 in diet

1f=% Cr2O3 in faecs

8. Survival rate (%)= ( (initial no.of fish stocked-mortality)/(initial no. of fish))x 100

Results and discussions

Table 3.4: growth performance and nutrient utilization of fishes fed SBM and WHM based

diets.

Parameter Diet 1 Diet 2 Diet 3

MWG (g) 23.08 14.79 19.13

WG(%) 67.38 56.84 63.05

Total feed intake (g) 76.43 79.64 80.11

SGR(%) 0.7 .52 0.62

Protein intake (g) 4.37 4.55 4.58

Nm 8.73 7.16 7.98

ADC (protein) 76.14 65.44 71.28

ADC (energy) 73.02 63.16 67.30

Survival rate (%) 100 100 100

From table 3.3, crude fiber was the highest in diet2 (WPM) and the lowest in diet 1 (SBM). Fish

that were fed diet 1 had the highest MWG, SGR. Fish under diet 2 had these in the lowest

amount. SBM (diet 1) is the conventional feed. But total feed intake and protein intake were

significantly higher in WHM based diets. Again, ADC was the highest in diet 1, diet 3 being the

intermediate and diet2 being the last. Survival rates were 100% for all, this is the most

important news.

Although temperature was constant throughout the experiment, pH and dissolved oxygen level

varied significantly for three different diet groups. Ammonia level was the highest in diet 2 and

the lowest in diet 1.

Lower weigh gain in WHM based diets may be due to their high fiber content. The results are in

line with Nwanna et al. (2008) who reported poor fish growth performance when fed diet with

crude fiber above 4.7% . Both WHM meals had fiber content much higher than this value.

Conclusion

This study reveals two important findings-

1. WLM is a better feed than WPM.

2. Only limitation for WPM as feed is high fiber content.

So, if water hyacinth leaves are processed in a suitable way, it can serve a dual purpose of

least cost fish diet and its effective mechanical control.

Study for Rohu fish

The previous study showed that unprocessed water hyacinth do not perform efficiently. In this

study, water hyacinth had been processed and showed tremendous good results.

Fishes do not like aquatic weeds like water hyacinth as their feed because of several factors-

1. Low protein content

2. Amino acid imbalance

3. Presence of antinutritional factor

4. Presence of crude fiber, cellulose, hemicellulose and lignin.

Most importantly Fish generally do not possess the enzyme cellulase significant

symbiotic gut flora capable of hydrolyzing the cellulose present in mcrophytes.

Why fermentation ?

It has been studied that inclusion rate can be done by adding enzymes to break down plant cell

walls so that nutritious cellular contents are liberated. Microbial fermentation is necessary in

organisms with diet which is high in fiber. Fermentation is the cheapest way to increase the

nutritional level through microbial synthesis.

While water hyacinth plant multiply at a rate of 15% of surface area per day, there must be some

processes to make this plant edible for fish and others- just to make a good use of it. So, this

study was performed.

Nine isoproteic (30% CP) and isocaloric (18.23 kJ/kg) experimental diets were made. One

reference diet was used as standard. Raw and fermented WH leaves were used in three different

proportion -20,30 and 40%.. water hyacinth leaves were fermented with fish intestinal bacteria.

Two specific strains of these bacteria were Bacillus subtilis CY5 (isolated from Cyprinus carpio) and B.

megaterium CI3 (isolated from Ctenopharyngodon idella) a commercial lactic acid bacteria (LAB) – Lactobacillus

acidophilus (lactobacil) was used along with B. subtilis CY5. The test specimen was Labeo

rohita, mostly herbivorous and very common in Asia.

Selected bacteria were allowed to grow in shake bottles containing 4% tryptone soya broth for

culture at 37oC for 24 hours to obtain viable cell no. 10^7/Ml broth. WH leaves were sundried

and ground, then moistened with a liquid basal medium whose composition is-

1. KH2PO4= 4g/L

2. NaHPO4= 4 g/L

3. MgSO4.7H2O= 0.2 g/L

4. CaCl2= 0.001 g/L

5. FeSO4.7H20= 0.004 g/L

Moistened leaves were autoclaved for sterilization. The sterilized leaf meal was inoculated with

B. subtilis and B. megaterium culture separately at the rate of 10^7 bacterial cells per gram of

dried leaf. It was kept for 15 days at 37 oC for fermentation.

Diet 1,2 and 3 were prepared with raw WH leaf meal. Diet 4,5 and 6 were prepared with B.

megaterium CI3 inoculated WH leaf meal. Diet 7,8 and 9 were formulated with WH leaf meal

fermented with B. subtilis CY5 with LAB. LAB was added at the rate of 10^6 cells per gram to

determine its synergistic effect. All diets contained 1% chromic oxide as digestibility marker.

Carboxymethylcellulose was used as binder.

Table 3.5 : composition (% dry weight) of experimental diets (on dry matter basis)

Ingredients Reference

diet

Diets with raw WH

leaf meal

Diets with WH leaf

meal fermented with

B. megaterium CI3

Diets with WH leaf

meal fermented with

B. subtilis CY5+LAB

D1 D2 D3 D4 D5 D6 D7 D8 D9

Fish meal 30 25 22 20 25 22 20 25 22 20

Soya bean

meal

35 30.33 33.58 34 30.33 33.58 34 28.71 30 31

Rice bran 32 21 11.41 3 21.66 11.41 3 23.28 15 6

WH leaf

meal

20 30 40 20 30 40 20 30 40

Cod liver

oil

0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5

Soya bean

oil

0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5

Vitamin

and

1 1 1 1 1 1 1 1 1 1

mineral

mixture

Chromic

oxide

1 1 1 1 1 1 1 1 1 1

Table 3.6: proximate composition (% dry weight)

Reference

diet

Diet

1

Diet

2

Diet

3

Diet

4

Diet

5

Diet

6

Diet

7

Diet

8

Diet

9

Dry

matter

99.75 99.9 99.9 99.9 99.91 99.93 99.94 99 99 99.93

Crude

protein

31.25 29.11 29.79 29.52 29.11 28.89 32 28.67 30.17 31.2

Crude

lipid

7.5 4.5 7.5 6 7.2 11 10 10 10 10.2

Ash 13 15.5 15 13 14 12.5 14 12 13 13.5

Crude

fiber

12 9.89 9.5 10 7.2 7.5 7.8 6.76 6.9 7.2

Nitrogen

free

extract

36 41 38.19 41 42 40 36.14 42.53 39.83 37.83

Gross

energy

(kJ/kg)

18.17 16.84 17.51 17.8 17.8 18.92 18.72 18.8 18.8 18.88

Tannin ND 0.1 0.2 0.3 ND ND ND ND ND ND

Phytic

acid

ND ND ND ND ND ND ND ND ND ND

Fishes were acclimatized to lab condition for 15 days and were fed a mixture of rice bran and

mustard oil cake (1:1). Rohu fingerlings of approximate weight of 4 gram were distributed at the

rate of 15 fishes per tank. This treatment had 3 replicates. All fishes were fed only once daily at

10:30 hours at a feeding rate of 3% of body weight for 80 days of experiment. Each day faecal

matter were collected by immediate pipetting method. Uneaten feed and faecal matters were

dried at 55oC and refrigerated for subsequent analysis. Water temperature varied in the range of

29-32 oC, pH level varied from 6.5 to 7.3 and dissolved oxygen level varied from 4.9 to 7.2

mg/L.

Experimental diets, faecal matter samples and fish carcass were analyzed according to AOAC

methods.

a) Moisture was determined by oven drying at 105oC for 24 hours.

b) Crude protein (N x 6.25) was determined by micro kjeldahl digestion.

c) Lipid was determined by extracting the residue with petroleum ether at 40-60 oC for 7-8

hours in a soxhlet apparatus.

d) Crude fiber was determined as loss in ignition of dried lipid free residues after digestion

with 1.25% H2SO4 and 1.25% NaOH.

e) Ash was determined by ignition at 550 oC in furnace at constant weight.

f) NFE was computed by taking the sum of CP,CL,CF and moisture and subtracting it from

100.

g) Cellulose and hemicellulose contents were determined according to Updegraff (1969) and

Goering and Vansoset (1975).

h) Total free amino acid and total free fatty acids in raw and fermented leaf meal were

performed according to Moore and Stein (1948) and Cox and Pearson (1962).

Table 3.7 : Growth performance and feed utilization efficiencies in fishes fed experimental diets

for 80 days.

Paramet

er

Referen

ce diet

Diet

s

Diets with

WH leaf

Diets

with WH

with

raw

WH

leaf

mea

l

meal

fermente

d with B.

megateriu

m CI3

leaf meal

fermente

d with B.

subtilis

CY5+LA

B

D1 D2 D3 D4 D5 D6 D7 D8 D9

Weight

gain (%)

64.75 60.5 60 59.5 79.75 81.2

5

70.7

5

77.25 74.5 69

Feed

intake

(g/100g

body

weight of

fish per

day)

1.33 1.35 1.36 1.39 1.24 1.22 1.26 1.26 1.27 1.30

FCR 2.7 2.88 2.92 2.99 2.25 2.19 2.44 2.32 2.39 2.55

PER 1.18 1.19 1.14 1.13 1.52 1.58 1.32 1.50 1.38 1.25

ANPU(

%)

27 36.9

6

18.2 20.9

4

73.22 83.6

4

82.2

3

79.79 87.0

2

70.5

APD(%) 80.71 80.5

1

79.9

6

79.8

3

81.41 86.7

8

82.4

7

81.29 82.0

1

82.2

3

SGR (%

per day)

0.63 0.59 0.58 0.58 0.73 0.74 0.67 0.71 0.69 0.65

Water hyacinth as duck feed

WH has the capacity of purifying the water and it can be used as duck feed too. These two

utilities are integrated in this following study.

Poultry breeding has developed recently on industrial scale. Household raising of duck is

environmentally safe, but when it is done industrially, it produces wastes of higher concentration

that need immediate treatment. Constructed wetland technology was used to treat the wastes.

What is constructed wetland ?

Constructed wetland (CW) is a relatively new waste water management technique which

developed in last three decades. CW is now applied in at least 26 states in the USA (Hunt and

Poach, 2001). Plants of these wetlands determine their capacity (Jing et al., 2001). Plants absorb

nutrient and promote all kinds of microbial functions (Brix, 1977). Floating plants like WH show

the greatest effect on eutrophic water in these kinds of wetland.

Lihong poultry ltd. is an egg-duck farm in China. About one-fourth of this farm is covered by

water. Duck manures are directly discharged to water where they live. This is certainly an

unhealthy practice.

So, a constructed wetland of 688 m2 was built. The integrated design approach included a

wetland plant where WH was used as water purifier and duck feed, both.

Figure : Sketch map of the experimental site

Figure : Process of wastewater treatment with water hyacinth and its recycling utilization

Methods

Ducks were randomly divided into two groups- experimental and control group. The experiment

was carried out for 40 days. The feeding trial was made for 30 days. Control group was fed with

basic date grain. Experimental group was fed basic date grain also, in addition fresh WH leaves

from CW. Water sample from duck pond and CW were collected every 4 day. Followings were

measured –

a) COD was measured by dichromate method.

b) Transparency was measured by Secchi disc.

c) DO was measured by electrochemical probe.

d) TP (total phosphorus) was determined by ammonium molybdate spectrophotometric

method.

e) TN (total nitrogen) was determined by persiflagedigestion UV spectrophotometric method.

Experimental group was fed 40 g of fresh WH leaves daily. Every 10 days, egg samples were

collected from 2 groups. Egg weight, egg shape index, egg shell thickness, egg shell strength,

haugh unit were measured. Egg shell strength were measured by INSTRON material testing

machine.

Changes in COD,DO and growth of WH due to CW technique

Table 3.8 : effect of CW technique on waste water from duck farm

Indicator Before treatment

(mg/L)

After treatment

(mg/L)

Removal rate (%)

COD 270 96 64.44

TP 8.86 6.82 23.02

TN 12.72 9.95 21.78

DO Not detectable 2.14

Figure : COD changes with time in CK, CW.

From table 3.8 and figure, it is seen that COD declined sharply for first 12 days due to high

temperature. It helped WH to grow. Growth of WH multiplied to 1.5% within 16 days. Then WH

growth and COD both tend to slow down. Growth of WH is shown in the following figure.

Figure : growth of WH with time

Decrease in COD and steady growth of WH plant can be explained. Plants transport oxygen

which increases removal of organic matter (Reddy and D Angelo,1997). When plants die their

decomposition consumes oxygen. So COD declined and WH need to be harvested regularly.

From table 3.8 and figure, it is seen that DO level was zero at the inflow of CW. After treatment,

it rose to 2.14 mg/L, which is above the standard value for China (2 mg/L). Like COD, DO level

also increased sharply for first 12 days.

Effects on egg production performance with water hyacinth as feed

Table 3.9 : effect on egg production performance of adding WH to diet

Index Test group Control group Increase rate (%)

Feed intake (gm) 176.63 166.85 5.86

Egg laying rate (%) 89.75 81.75 9.79

Egg weight (gm) 65.59 64.08 2.36

Feed conversion ratio 2.87 2.97

From table 3.9, it is well understood that except feed conversion ratio, all index show a good

increase.

Effects on egg quality with water hyacinth as feed

Table 3.10 : effect on egg quality of adding WH to diet

Group Egg shape

index

Egg shell

thickness

(mm)

Egg shell

strength (N)

Haugh unit Egg shell

relative

weight

Test 1.32 0.58 36.65 76.6 0.11

Control 1.30 0.53 31.33 80.98 0.11

Egg shell strength indicates egg damage rate. It is linked with egg shell’s thickness, porosity,

membrane thickness, mineral and protein content (Dai, 2001). WH clearly increased the egg

shell strength. High haugh unit indicates good egg CP (Dai, 2001). Haugh unit was lower in test

group than control group.

This experiment was run at autumn. What happens at temperature below zero degree is still

unknown. Long term use of this wetland also needs further research.

WATER HYACINTH AS GOAT FEED

this study was made at Animal Nutrition Laboratory, Bangladesh Agricultural University,

Bangladesh to determine the usability of water hyacinth leaves as feed for goat.

about 8.75 million goats are in Bagladesh who live on kitchen wastes and roadside

grass(BBS,1986). it results in malnutrition and less productivity of goats. necessity of

unconventional feed like WHL arises during natural calamity when WH becomes only available

green fodder. limited works have been done in Bangladesh using WH in diet of cattle

(Khan,1977, Reza,1988). this study aimed to replace Dhal grass with WH as diet of goat.

Methods

the experiment ran for 60 days. WH leaves, dhal grass and a mixture of weat bran, seasame

oilcake and fish meal were the feed ingredients. they were sundried. proximate composition of

feeds and feces of goats were analyzed following AOAC method (1980).

12 black bengal goats were divided among 4 groups. 4 different diets were made for 4 different

groups.

Diet A = 100% dhal grass (DG)

Diet b = 75% DG + 25% WHL

Diet c =50% DG +50% WHL

Diet D = 100% WHL.

4 groups were fed these ad libitum throughout the experiement. feeds were provided twice a day,

at 8:00 a.m. and 4 p.m. the following table shows the proximate compositon of this feed.

Table 3.11: proximate composition of feed.

feed DM CP CF Ether Ash NFE OM

ingredient extract

WHL 15.33 20.8 16.15 4.37 13.43 45.25 86.57

DG 17.82 12.35 38.67 3.45 16.63 28.9 83.37

wheat

bran

88.52 14.9 15.19 4.39 7.08 58.44 92.92

Till oil

cake

91.82 35.16 23.52 5.52 9.98 25.82 90.02

Fish meal 84.6 48.73 4.05 7.5 27.6 12.12 72.4

( all quantity are in g/100 g DM basis)

It is clearly seen that WHL contains higher percentage of CP,NFE,OM and lower percentage of

CF than that of dhal grass. so, WH has definitely higher nutritive value than DG.

Effect of WHL in diet on growth performance of goats

coefficient of digestibility of different nutrients were calculated as follows –

COD of nutrient = (g nutrient provided – g nutrient refused – g nutrient in feces)/ (g nutrient

provided – g nutrient refused) x 100

Table 3.12 : effect of diets on growth performance

group no. of goats avg. live weight

gain by 60 days

(kg)

total amount of

feed consumed

by 60 days on

DM basis (kg)

feed conversion

efficiency

1 3 1.76 28.34 16.19

2 3 1.63 29.32 17.99

3 2 1.37 26.02 18.26

4 3 1.03 26 24.27

from this table 3.12 , highest feed intake was in group 2 (diet B). group 1 (diet A) showed

intermediate feed intake. group 4 (diet C) showed the lowest. it means, WHL as sole diet cannot

be used for goats. but when it is mixed with dhal grass, it increases palability of the mixed diet.

this results in better body weight gain. these results are in line with findings of Hossain (1959),

Gupta et al. (1975) and Reza (1988).

Conclusion

It is not the right time to recommend water hyacinth as the best alternative food stuff for

animals. It is obviously clear that it is economically feasible. But further research is

immediately needed to evaluate its effect on growth and halth of animals. Because in the

end, if animals are fed with wrong food, we shall be affected too as we eat them.