9. Feed intake, digestibility and N retention of a diet of water spinach supplemented with palm oil and / or broken rice and dried fish for growing pigs
Authors: Prak Kea, Preston T R and Ly J 2003
Livestock Research for Rural Development (15) 8 Retrieved, from
Summary: The experiment was carried out from May to June, 2002 in the Ecological Farm of the University of Tropical Agriculture (UTA), in Chamcar Daung, about 12 km from Phnom Penh. The average annual temperature in this location is in the range of 26 to 31 ° C. Four crossbred castrated male pigs of average weight 9.5 kg were allocated to 4 dietary treatments (levels of palm oil of 0 [po0], 5 [po5], 10 [po10] and 15% [po15]), according to a 4*4 Latin square arrangement with 4 periods each of 10 days, 5 for adaptation and 5 for collection of faeces and urine. The daily dry matter (DM) allowance was calculated at 5% of the body weight. The water spinach was purchased daily in the local market and was chopped into small pieces prior to offering it in one of two feed troughs; the other feed trough was used for the dry components (supplements) of the diet which were mixed before feeding. The daily allowances of the supplements were weighed and put in small polyethylene bags (2 kg capacity) in sufficient numbers for each 10-day experimental period. The pigs were fed twice daily, first at 7 am and then in the afternoon at 4 pm. The water spinach was offered after the pigs had consumed the supplements. Water was offered ad libitum through the automatic drinking nipples. The pigs were penned in metabolism cages made from rattan and bamboos strips fixed to a wooden frame in a composite unit (1.6m length and 0.7m wide) for 2 animals per unit. Plastic netting was suspended below the floor to collect the faeces. The urine passed through the plastic net and was collected over a sheet of polyethylene leading to a filter placed in a funnel suspended over a plastic bucket containing sulphuric acid (10 ml of 4N acid) so as to maintain the pH below 4.0. The floor area of each metabolism cage was 80*80 cm. During the 5-day collection period, the faeces were collected daily just before each morning feeding and kept in polyethylene bags at -20 o C. The total volume of urine was recorded daily and 10% of the total collection for each day was kept in plastic containers at -20 o C until the end of the experiment. At the end of the collection period the faeces were thawed and mixed thoroughly to provide a representative sample for each pig. The pigs were weighed at the beginning of the experiment and then every 10 days. The feed refused was weighed and recorded daily and a sample was kept for analysis. Dry matter, nitrogen and crude fibre were determined in feed offered and refused and in faeces. The urine was analysed for N. The chemical analyses were done following standard procedures according to AOAC (1988), except for DM which was determined by micro-wave radiation (Undersander et al 1993). The NDF was determined according to Van Soest et al (1991).
Abstract: The aim of the study was to determine the effect of different ratios of palm oil and broken rice on the intake, apparent digestibility and nitrogen retention by crossbred pigs of diets based on fresh water spinach (WS) supplemented with fish meal. Four castrated crossbred male piglets of 8-10 kg initial live weight were used in the trials. They were housed in individual cages and allocated to four treatments according to a 4 * 4 Latin square arrangement. The treatments were four diets in which water spinach was progressively substituted by 0, 5, 10 and 15% of palm oil. The diets were supplemented with fish meal to contain 15 % crude protein (Nx6.25). The dry matter feed intake as a percentage of DM offered, and the apparent digestibilities of dry matter and organic matter decreased, as the proportion of palm oil increased. Level of palm oil had no effect on digestibility of crude fiber and N, nor on N retention. It is concluded that fresh water spinach can provide up to 70% of the dietary protein for growing pigs, when it is supplemented with broken rice and up to 15% of palm oil.