Published January 23, 2015
Digestible and metabolizable energy concentrations in copra meal, palm kernel meal, and cassava root fed to growing pigs1 A. R. Son,* S. Y. Ji,† and B. G. Kim*2 *Department of Animal Science and Environment, Konkuk University, Seoul 143-701, Republic of Korea; and †Animal Nutrition and Physiology Team, National Institute of Animal Science, Rural Development Administration, Suwon 441-706, Republic of Korea
ABSTRACT: An experiment was conducted to measure DE and ME in copra (Cocos nucifera) meal (CM), palm kernel meal (PKM), and cassava (Manihot esculenta) root (CR) in growing pigs. Eight boars with an initial BW of 67.3 ± 5.8 kg were individually housed in metabolism crates that were equipped with a feeder and a nipple drinker. A replicated 4 × 4 Latin square design was used with 4 dietary treatments, 4 periods, and 8 animals. A basal diet mainly contained corn (Zea mays) and soybean (Glycine max) meal. Three additional diets were formulated to contain 30% of CM,
PKM, and CR. All diets contained the same proportion of corn:soybean meal ratio at 4.14:1. The apparent total tract digestibility of energy was 89.5, 84.1, 82.4, and 87.9% (P < 0.001) in the basal, CM, PKM, and CR diets, respectively. The DE in CM and PKM were greater (P < 0.05) than in CR (3440 and 3238 vs. 2966 kcal/kg asfed). The ME in CM was greater (P < 0.05) than in CR (3340 vs. 2935 kcal/kg as-fed) but not different from the ME in PKM (3168 kcal/kg as-fed). In conclusion, CM and PKM have a higher DE value than CR, and CM has a higher ME value than CR.
Key words: cassava root, copra meal, digestibility, energy, palm kernel meal © 2012 American Society of Animal Science. All rights reserved. INTRODUCTION
J. Anim. Sci. 2012.90:140–142 doi:10.2527/jas53822
and CR fed to growing pigs.
In recent years, the prices of conventional feed ingredients such as corn and soybean meal (SBM) have sharply increased. So cheaper feedstuffs that can, at least partly, replace conventional feedstuffs have become important. Copra meal (CM) and palm kernel meal (PKM) are produced by extracting oil from dried coconut kernels and palm nut kernels, respectively. Copra meal, PKM, and cassava root (CR; tapioca) contain 4232, 4466, and 3556 kcal GE/kg on an asfed basis, respectively (Table 1). Although the GE concentrations in CM and PKM are much greater than in CR, the DE and ME content in CM and PKM are lower than in CR (Sauvant et al., 2004). On the other hand, the DE and ME content in CM and PKM in other studies (Agunbiade et al., 1999; O’Doherty and McKeon, 2000) are 62 to 103% greater than the values provided by Sauvant et al. (2004). To address this discrepancy, we determined DE and ME of CM, PKM,
MATERIALS AND METHODS Animals, Diets, and Feeding The protocol for the experiment was approved by the Institutional Animal Care and Use Committee at Konkuk University. Eight boars with an initial BW of 67.3 ± 5.8 kg were used to determine the DE and ME of CM, PKM, and CR. The pigs were placed in metabolism cages and were allotted to 4 dietary treatments in a replicated 4 × 4 Latin square design using a systemic method (Kim and Kim, 2010). A basal diet contained corn and SBM as main ingredients (Table 2). Three additional diets were formulated to contain 30% of CM, PKM, or CR. All diets contained the same proportion of corn:SBM ratio at 4.14:1. The amount of feed provided daily per pig was calculated as approximately 3% of BW and divided into 2 equal meals. Sample Collection and Chemical Analyses
1 This manuscript is based on research supported by Easy Bio System (Seoul, Republic of Korea) and National Institute of Animal Science (Suwon, Republic of Korea; PJ907038). 2 Corresponding author:
[email protected]
An experimental period consisted of a 4-d adaptation and a 4-d collection. Feces were collected according to the marker-to-marker procedure (Adeola, 140
141
Energy in swine feed ingredients
Table 1. Energy and nutrient composition of copra meal (CM), palm kernel meal (PKM), and cassava root (CR) Ingredient
Table 2. Ingredient composition of experimental diets Diet1 Item
Composition, as-fed
CM
PKM
CR
DM, % GE, kcal/kg CP, % Ether extract, % Ash, % Ca, % P, % NDF, % ADF, %
88.7 4232 21.0 7.46 6.71 0.11 0.55 54.5 27.4
92.6 4466 16.9 6.74 4.02 0.28 0.66 68.3 37.8
88.1 3556 4.01 0.52 6.77 0.51 0.12 19.4 10.4
2001) using Cr2O3 as a marker. Urine was collected from 1400 h on day 5 to 1400 h on day 9. Fecal samples were dried in a forced-air drying oven at 55°C and ground before analysis. Diets, feces, and urine were analyzed for GE using a bomb calorimeter (C 2000; IKA, Staufen, Germany). Diets and ingredient samples were analyzed for DM, CP, ether extract, crude fiber, ash, Ca, P, NDF, and ADF (AOAC, 2005). Calculations and Statistical Analyses The content of DE and ME in experimental diets and ingredients were calculated by the procedures described by Adeola (2001). Data were analyzed using the MIXED procedure of SAS (SAS Institute Inc., Cary, NC). The model included dietary treatment as fixed variable and replication, animal within replication, and period within replication as random variables. Differences among least squares means were tested using the PDIFF option with the Tukey’s adjustment. The CORR procedure was used to correlate dietary NDF and energy digestibility. The experimental unit was a pig, and significance was determined at an α of 0.05. RESULTS AND DISCUSSION Energy digestibility was the greatest (P < 0.05) in the basal diet followed by the CR, CM, and PKM diets
Ingredient, % as-fed Ground corn Soybean meal, 48% CP CM PKM CR Vitamin–trace mineral premix2 Others3 Analyzed composition, as-fed DM, % GE, kcal/kg CP, % Ether extract, % NDF, % ADF, %
Basal
CM
PKM
CR
78.60 19.00 – – – 0.50 1.90
54.44 13.16 30.00 – – 0.50 1.90
54.44 13.16 – 30.00 – 0.50 1.90
54.44 13.16 – – 30.00 0.50 1.90
86.7 3877 14.9 2.64 17.9 3.60
86.9 4080 15.3 4.15 29.3 10.9
88.3 4091 14.9 3.40 35.6 12.8
87.4 3742 11.4 1.74 19.8 4.91
CM = copra meal; PKM = palm kernel meal; CR = cassava root. Met or exceeded requirement estimates (NRC, 1998) for all vitamins and trace minerals. 3 0.70% ground limestone, 0.80% CaHPO4, and 0.40% salt. 1 2
(Table 3). The energy digestibility values in the diets were negatively correlated (r = –0.92; P < 0.001) with the NDF concentrations in the diets similar to Ravindran et al. (1984). The DE content in the CM and PKM diets was greater (P < 0.05) than in the CR diet. Despite the lower (P < 0.05) energy digestibility in the CM and PKM diets compared with the CR diet, DE values were greater (P < 0.05) in the CM and PKM diets because of the greater GE than in the CR diet (Table 2). As the urinary energy output did not differ among the diets, the ME content in the CM and PKM diets was also greater (P < 0.05) than in the CR diet. The DE content in CM and PKM was greater (P < 0.05) than in CR. The ME content in CM was greater (P < 0.05) than in CR. The DE and ME values for CM and PKM measured in the present experiment were relatively close to previous studies (Agunbiade et al., 1999; O’Doherty and McKeon, 2000). However, the DE and ME content in CM and PKM in the present study were much greater than those reported by Sauvant et al.
Table 3. Digestibility of experimental diets fed to growing pigs and DE and ME content of experimental diets and ingredients1 Diet or ingredient2 Item, as-fed Energy digestibility of diet, Diet DE, kcal/kg Diet ME, kcal/kg Ingredient DE, kcal/kg Ingredient ME, kcal/kg
3%
Basal
CM
PKM
CR
89.5 3470a 3396a – –
84.1 3432ab 3350ab 3440a 3340a
82.4 3372b 3299b 3238a 3168ab
87.9 3290c 3229c 2966b 2935b
a
c
d
b
SEM
P-value
0.5 18 27 70 103
