Agricultural potential and utilization of water hyacinth (Eichhornia crassipes) as forage for fattening pigs in the Mekong delta of Vietnam

Nguyen Ba Trung

Department of Animal Husbandry, Faculty of Agriculture, An Giang University, An Giang, Vietnam
nbtrung@agu.edu.vn

Abstract

Experiment 1 was carried out to determine the biomass production and chemical composition of water hyacinth (WH) grown in different environments. There were two factors: A, water environment, either river or pond, and factor B, regeneration method, either saplings or natural regeneration. Water environment did not affect WH yield, ether extract or ash content of the leaves. However, WH grown on pond surfaces contained more crude protein (CP) and neutral detergent fiber than that grown in the river. Conversely, CP of WH stem grown in the river was higher than that grown on a pond surface. Experiment 2 was conducted in order to determine the effect of using cooked fresh leaves and stems of WH as a supplement in commercial concentrate diets of fattening-finishing pigs. A feeding trial was carried out on 57-100 kg Yorkshire pigs kept in the Experimental Animal Farm of Can Tho University. Using cooked/fresh leaves/stems of WH did not statistically affect performance and feed efficiency of the fattening-finishing pigs (P>0.05). Supplementing cooked or fresh WH did not affect daily weight gain, feed efficiency or back-fat thickness of the experimental pigs.

Key words:  back-fat thickness, biomass production,  chemical composition, feed intake, feed conversion, regeneration method, water hyacinth,

Introduction

Water hyacinth (Eichhornia crassipes) is a perennial aquatic herb, which belongs to the family Pontedericeae. It is usually found floating freely on the surface of fresh water or can be anchored in mud. Using water hyacinth as a feed is one of the methods to limit the disadvantagous effects of the plant and to provide a low-cost ingredient in animal diets. Thus, water hyacinth is considered to be a plant for hunger and poverty alleviation in several developing countries.

Studies have shown that the nutrients of water hyacinth are available to ruminants. In Southeast Asia, however, some non-ruminant animals are fed rations containing water hyacinth. In Malaysia fresh water hyacinth is cooked with rice bran, copra cake, fish meal and then mixed with copra meal as feed for pigs, ducks, and pond fish. Similar practices are much used in Indonesia, the Philippines and Thailand (National Academy of Sciences 1976). In Vietnam, studies have proved that farmers can use fresh or ensiled water hyacinth in the diets of fattening pigs (Luu Huu Manh et al 2002; Le Thi Men et al 2002; Nguyen Nhat Xuan Dung et al 2002). The effect of using the plant as a supplement in commercial concentrates for pigs, however, has not been studied.

The objectives of the experiment were to determine the production and chemical composition of water hyacinth (WH) grown in different environments and to evaluate the effects feeding fattening pigs diets containing water hyacinth in different forms on feed intake, feed conversion ratio and daily weight gain.

Material and methods

Experiment 1: Effect of environment and regeneration method on biomass yield and chemical composition of water hyacinth

The experiment was conducted at My Hoa, in Long Xuyen City, as a completely randomized factorial design: Factor A was water environment (river or pond) and factor B regeneration method (saplings or natural regeneration). Each treatment was replicated three times. At each selected site, a 1m x 1m bamboo frame was placed to contain the growing water hyacinth plants and the biomass productivity determined when the water hyacinth tightly covered the frame (see Figures 1 and 2.).

 

Figure 1. Growing WH in the river	Figure 2. Growing WH in a pond

 

Experiment 2: Effect of feeding cooked or fresh leaves or stems on the performance of Yorkshire fattening pigs

Experimental design

Experiment 2 was carried out at the Experimental Farm of Can Tho University, in the Mekong Delta. Twenty Yorkshire pigs at around 60kg live weight were allocated in a completely randomized design, with 5 treatments and 4 replications (individually housed pigs)

Feed ingredients

The experimental pigs in all treatments were given a commercial concentrate (Table 1) and WH (Table 2) according to the proposed treatments. 

 

Results and Discussion

Experiment 1

The water environment did not affect WH yield, or ether extract and ash content of the leaves. However, WH grown on a pond surface contained more crude protein (CP) and neutral detergent fiber than that grown in a river. Conversely, the CP content of WH stems grown in a river was higher than that grown on a pond surface.

 

 

Experiment 2

Growth performance, feed conversion efficiency and carcass quality

There was no effect of treatment on the weight gain of the finishing pigs (Table 4).

In treatment CL water hyacinth intakes were higher than in treatment FS (P<0.05), with intermediate intakes in treatments CS and FL . However, there was no significant difference in total feed intake or FCR among treatments (P>0.05).

There was no effect of feeding cooked or fresh water hyacinth leaves or stems on back-fat thickness (P>0.05) (Table 6).

Table 6. Effect of treatment on back-fat thickness
Treatment	Back-fat thickness, mm
CO	10.1
CS	10.6
FS	10.1
CL	11.4
FL	11.0

Conclusions and Recommendations

• Water environment did not affect the yield of water hyacinth, or ether extract and ash content of the leaves. However, water hyacinth grown on pond surfaces contained more crude protein (CP) and neutral detergent fiber than that grown in a river. Conversely, the CP content of stems grown in a river was higher than that grown on pond surfaces.

• Supplementation of cooked or fresh water hyacinth in finishing diets did not affect performance and feed efficiency, and also did not decrease the concentrate intake of the pigs. The results indicate that farmers could use water hyacinth, offered ad-libitum, as a supplement for fattening pigs.

References

Gopal B 2002:Water hyacinth. Jawaharlal Nehru University, New Delhi.

Kangmin L 2002: The water hyacinth issue in China. http://www.zeri.org

Le Thi Men et al 2002:Evaluation of water hyacinth diets for fattening pigs in Tan Phu Thanh village. JIRCAS workshop proceedings. Can Tho Vietnam.

Luu Huu Manh et al 2002: Replacement of concentrate protein by water hyacinth in the diets of growing-finishing pigs. JIRCAS workshop proceedings. Can Tho Vietnam.

National Academy of Sciences 2002: Making aquatic seeds: some perspectives for developing countries. No26.

Nguyen Nhat Xuan Dung et al 2002: Water hyacinth: Ensiling techniques, its nutritive values and intake of pigs. JIRCAS workshop proceedings. Can Tho Vietnam.

Go to top