Effect of rice bran as a supplement for growing rabbits with basal diet of water spinach

Thim Sokha

Royal university of Agriculture, Cambodia
Sokha_rua@yahoo.com

Introduction

In most developing, tropical countries such as Laos, Vietnam and Cambodia, farmers keep livestock like cows, buffaloes, pigs, fish and poultry for their main source of income. Small animals like chickens, ducks and rabbits are used for home consumption. However, productivity is low and there is a lack of feed resources, particularly in the dry season. 

Water spinach is easy to plant and has a very high yield of biomass, which is rich in protein. The crude protein content in the leaves and stems can be as high as 32 and 18 % in dry basis, respectively (Ly Thi Luyen 2003). Water spinach (Ipomoea aquatica ) has a very high biomass yield. It is used traditionally in tropical regions for consumption by people and animals. It has given good results fed topigs (Le Thi Men et al 1999). Water spinach has a short growth period. It can grow both in soil and in water and it is very easy to grow by farmers for selling in the market and is the feed for all kinds of animals. Water spinach is a plant which produces high yields of protein-rich biomass when fertilized with effluent from biodigesters (Kean Sophea and Preston 2001; Ho Bunyeth 2003). Other recent information indicates that the crude protein of water spinach can be increased to over 30% in the dry matter of the leaves when the plant is fertilized with biodigester effluent (Ho Bunyeth 2003) or with urea (Ly Thi Luyen 2003).

The rabbit is a meat-producing animal which is especially well adapted to utilization of protein-rich foliages due to the nature of its digestive system in which enzymatic digestion (in the stomach) precedes microbial fermentation (in the caecum. Preliminary results (Hongthong Phimmmasan et al 2004) indicated acceptable growth rates (12 to 18 g/day) on a diet of ad libitum water spinach.  However, recent findings from Cambodia (Samkol 2005) indicated that the fibre conent in water spinach may be too low to support optimum performance. Further work on the use of water spinach for rabbit production is therefore needed in view of the potential of the system for increasing the income of small scale farmers with minimum outside inputs.

Hypothesis

• The hypothesis rate of rabbits fed a basal diet of water spinach will be increased when they have access to rice bran.

Objective

• To compare growth rates of young rabbits fed water spinach ad libitum and graded levels of rice bran.

 

Materials and methods

Location

The experiment will be carried out in the Livestock Research Centre of NAFRI, in Nam Xuang about 44 km from Vientiane city, Lao PDR. The experiment will start on18 Sep 2005 and continue to 8 Oct 2005.

Animals and treatments

Ten young rabbits in individual cages (average 590 g live weight) will be allotted at random into five treatments consisting of fresh water spinach (Ipomoea aquatica) given at libitum and five levels of rice bran (0, 3, 6, 9 and 12 g/rabbit per day). They will be allocated to two b locks according to live weight The design will be a randomized block with blocks being the replications (Table 1).

Table 1 : Layout of the treatments
Block 1	Cage1	Cage2	Cage3	Cage 4	Cage 5
	WSB-9	WSB-3	WSB-6	WS-0	WSB-12
Block 2	Cage6	Cage 7	Cage 8	Cage 9	Cage 10
	WSB-12	WSB-9	WS-0	WSB-6	WSB-3

 

Feeding system

Rice bran will be bought from the local market. Water spinach (leaves attached to stems) will be harvested daily from plots in the Livestock Research Center and suspended in the cage with a wire around the stems. Water spinach will be offered 2 times per day (Morning and evening). The rice bran will be feed only one time in a small bowl every morning, when feed refusals from the previous day will be recorded. The rabbits will be adapted to confinement in individual cages during a preliminary period of three days after which the experiment will be started.

Animal housing

The cages are made from wood and iron net with dimensiona of length 0.5m, width 0.5m and height 0.5 m with spaces in the floor of approximately 1 cm².

Measurements

Measurements will be make of daily water spinach offered and refused (leaves and stem proportions are estimated every 3 days in both offered and refused water spinach). The rabbits will  be weighed at the beginning and thereafter every 5 days.Feeds and refusals are analysed for DM by micro-wave radiation (Undersander et al 1993) and OM and N following the methods of and AOAC (1990). Water soluble DM and N  determined  by the method of Ly et al (1997).

Statistical analysis

Growth rates of the rabbits will be calculated as the slope of the linear regression of live weight (y = g) on time in the experiment (x = days). Response data (weight gain, feed intake and feed conversion will be regressed against level of rice bran using the regression options in the Microsoft  Excel software.
 

References

AOAC 1990 Official Methods of Analysis. Association of Official Analytical Chemists. 15^th edition (K Helrick editor) Arlington pp 1230

Ho Bunyeth 2003 Biodigester effluent as fertilizer for water spinach established from seed or from cuttings; Retrieved , from MEKARN Mini-projects. http://www.mekarn.org/msc2003-05/miniprojects/webpage/buny.htm

Hongthong Phimmmasan, Siton Kongvongxay, Chhay Ty and Preston T R 2004 Water spinach (Ipomoea aquatica) and Stylo 184 (Stylosanthes guianensis CIAT 184) as basal diets for growing rabbits. Livestock Research for Rural Development. Vol. 16, Art. # 34. Retrieved from http://www.cipav.org.co/lrrd/lrrd16/05/hong16034.htm.

Kean Sophea and Preston T R 2001Comparison of biodigester effluent and urea as fertilizer for water spinach vegetable. Livestock Research for Rural Development (13) 6; http://www.cipav.org.co/lrrd/lrrd13/6/Kean136.htm.

Ly J, Nguyen Van Lai and Preston T R 1997 A study of washing losses and in vitro gas production characteristics of nine leaves from tropical trees and shrubs for ruminants. Livestock Research for Rural Development. http://www.cipav.org.co/lrrd/lrrd9/3/ly93.htm.htm

Le Thi Men, Ogle B and Vo Van Son 1999 Evaluation of water spinach as a protein source for Baxuyen and Large White sows and fattening crossbred pigs. MSc thesis, Swedish University of Agricultural Sciences, Uppsala

Ly Thi Luyen 2003 Effect of the urea level on biomass production of water spinach (Ipomoea aquatica) grown in soil and in water; Retrieved, from MEKARN Mini-projects. http://www.mekarn.org/msc2003-05/miniprojects/webpage/luyen.htm

Pok Samkol 2005: Effect of increasing offer level of water spinach (Ipomoea aquatica) on intake, growth and digestibility coefficients of rabbits. http://www.mekarn.org/msc2003-05/theses05/samkol3.pdf

Undersander D, Mertens D R and Thiex N 1993Forage analysis procedures National Forage Testing Association. Omaha pp:154