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Effect of cassava bioethanol by-product and crude palm oilin Brahman x Thai native yearling heifer cattle diets: I. Nutrientdigestibility and growth performance

Chirasak Phoemchalard & Suthipong Uriyapongson &

Eric Paul Berg

Accepted: 29 January 2014# Springer Science+Business Media Dordrecht 2014

Abstract The effects of cassava bioethanol by-product (CEP)and crude palm oil (CPO) on feed intake, nutrient digestibility,and growth performance of yearling heifers were investigatedin a 150-day feeding trial. Eighteen, crossbred heifers(Brahman x Thai native) were randomly allotted accordingto 2×3 factorial arrangement. Low or high levels of CEP (15or 30 % of concentrate, LCEP, or HCEP) were basal treat-ments and 0, 2, and 4 % CPO were daily top-dressed.Concentrate was supplemented at 1.75 % of body weight(BW) and rice straw offered ad libitum. CEP level had nosignificance on feed intake. CPO increased roughage intake,concentrate intake, and total feed intake when expressed as%BW/d (P<0.01) and as metabolic BW (kg0.75/d, P<0.05).Intakes of dry matter (DM), organic matter (OM), and crudeprotein (CP) were similar (P>0.05). Intake of fat increasedwith higher levels of CPO (P<0.001). The DM, OM, CP, andEE digestibility of cattle-fed HCEP was lower than LCEP, butadding 4 % CPO increased digestibility. Growth performancewas similar for all diets (P>0.05).We concluded that CEP canbe used up to 30 % in the diet, with or without additional fatinclusion.

Keywords Digestibility . Performance . Cassava .

By-product . Crude palm oil . Heifer

Introduction

Cassava is one of the main feed stocks for the bioethanolindustry in Thailand (Sriroth et al. 2010), for reasons ofeconomic and government planning—it is associated withlow price and high yield Trovati et al. 2009﴿. After process-ing, fermentation, and distillation of alcohol, the remainingresidue contains nutritional components (Nuez Ortín and Yu2009). Robinson et al. (2008) reported that differences innutritive value of each by-product of bioethanol productionare due to material and processing procedures. Corn, wheat,barley, rye, and sorghum are the best known by-products frombioethanol production. They are referred to as distillers driedgrains with solubles (DDGS, Gibb et al. 2008). Many re-searches have studied these products for animal feeding, butlittle is known about cassava by-product nutrient density andits potential for use as an animal feedstuff. Cassava bioethanolby-product (CEP) is a residual product that is obtained fromethanol processing which uses cassava chips, cassava pulp, orwhole cassava root as the raw material for ethanol production.Although this by-product is high in moisture (90 %) and ash(26 % of DM), nutrients remain available for animals(Table 2).

Supplementation of vegetable oil such as sunflower oil(SFO), soybean oil, canola oil, etc. have been widelyresearched as animal feedstuffs (Bernard et al. 2009). It hasbeen shown that adding fats to the diets can affect intake anddigestibility (Lunsin et al. 2012). Crude palm oil (CPO) is anatural oil rich in vitamin E and carotenoid (Gapor et al.1983). There is little information regarding the use of CPO(gross energy=9.2 kcal/g) as energy sources in a diet CEP-based ruminant diet. Therefore, the aim of this study was toinvestigate the effects of CEP and CPO on feed intake,

C. Phoemchalard : S. Uriyapongson (*)Department of Animal Science, Faculty of Agriculture, Khon KaenUniversity, KhonKaen 40002, Thailande-mail: suthipng@kku.ac.th

E. P. BergDepartment of Animal Science, NDSU Department 7630, NorthDakota State University, Fargo, ND 58108-6050, USA

Trop Anim Health ProdDOI 10.1007/s11250-014-0549-x

nutrient digestibility, and growth performance of young cross-bred heifers.

Materials and methods

The experiment was conducted at the Animal ScienceExperimental Farm, Khon Kaen University, Thailand (16°26′ N, 102° 50′ E). Mean annual temperature, relative humid-ity, and rainfall are 28 °C, 77 %, and, 1,195 mm, respectively.This research was carried out from January to June of 2013,when the averages were 29 °C, 81 %, and 43 mm.

Animals, diets, and experimental design

A total of 18, 1-year-old crossbred heifers (Brahman x Thainative) with average body weight of 130±14 kg were vacci-nated with foot and mouth disease vaccine type O, A, AsiaI aqueous (2 cc/head), hemorrhagic septicemia vaccine

(1 cc/head), and treated with Ivomec F® (1 cc/50 kg BW) andvitamins AD3E (1 cc/20 kg BW). Animals were housed inindividual pens (3×5 m), placed in pens for a 14-day adapta-tion period followed by 150-day trial. The cattle were ran-domly allotted to receive CEP at 15 % of concentrate (LCEP)or 30 % of concentrate (HCEP) as basal diets. Also, threelevels of crude palm oil ((CPO) 0, 2, and 4 %) were added tothe basal diets as top dressings and completed the 2×3 facto-rial arrangement. Six dietary treatments were randomlyassigned to three animals per treatment group. The dietarytreatments were as follows: 15%CEP+0%CPO (LCEP0),15%CEP+2%CPO (LCEP2), 15%CEP+4%CPO (LCEP4),30%CEP+0%CPO (HCEP0), 30%CEP+2%CPO (HCEP2),and 30%CEP+4%CPO (HCEP4). The concentrate diets werefed at 1.75 %BW twice daily at 8:30 a.m. (after at least 30 minroughage offered) and 4:30 p.m., while rice straw and cleanfresh drinking water were available ad libitum throughout thetrial. The ingredients and chemical composition of experimen-tal diets are showed in Tables 1 and 2.

Data collection and sampling procedures

Feed and feed refusal of concentrates and roughage wererecorded daily. Cattle were weighed every 30 days in themorning prior to feeding to measure body weight change.Feeds samples were collected at 8 a.m. daily, and fecal sam-ples were collected by grab sampling at 10 a.m.–1 p.m. duringthe last 7 days on test. Feed and fecal samples were stored inrefrigerator at −20 °C until analysis. Concentrate and fecalsamples were dried and grounded through a 1-mm screenusing grinder (Cyclotech Mill, Tecator). All samples wereanalyzed in triplicate for dry matter (DM), organic matter(OM), crude protein (CP), and ether extract (EE) accordingto the Association of Official Analytical Chemists (1997).Neutral detergent fiber (NDF) and acid detergent fiber(ADF) were analyzed according to Van Soest et al. (1991).Acid insoluble ash (AIA) was also evaluated according to VanKeulen and Young (1977). Metabolizable energy (ME) of

Table 1 Ingredients of experimental diets

Items LCEP HCEP

CPO, % 0 2 4 0 2 4

CEP 15.0 15.0 15.0 30.0 30.0 30.0

Cassava chip 38.0 38.0 38.0 30.0 30.0 30.0

Soybean meal 2.8 2.8 2.8 4.8 4.8 4.8

Rice bran 6.0 6.0 6.0 5.0 5.0 5.0

Palm meal 19.0 19.0 19.0 9.0 9.0 9.0

Copra meal 14.0 14.0 14.0 16.0 16.0 16.0

Sulfur 0.2 0.2 0.2 0.2 0.2 0.2

Urea 2.5 2.5 2.5 2.5 2.5 2.5

Salt 1.0 1.0 1.0 1.0 1.0 1.0

Mineral mixture 1.0 1.0 1.0 1.0 1.0 1.0

Lime stone 0.5 0.5 0.5 0.5 0.5 0.5

CEP cassava bioethanol by-product, LCEP low cassava bioethanol by-product,HCEP high cassava bioethanol by-product, CPO crude palm oil

Table 2 Chemical compositionof experimental diets (% of drymatter)

CEP cassava bioethanol by-prod-uct, LCEP low cassava bioethanolby-product, HCEP high cassavabioethanol by-product, RS ricestraw, CPO crude palm oila Calculated according to NRC(2000)b Calculated according to Menkeet al. (1979)

Items LCEP HCEP CEP RS

CPO, % 0 2 4 0 2 4

Dry matter 93.0 93.0 93.0 93.7 93.7 93.7 91.0 94.1

Organic matter 85.5 85.5 85.5 83.1 83.1 83.1 73.7 85.9

Crude protein 16.0 16.0 16.0 14.0 14.0 14.0 5.9 3.6

Ether extract 5.1 7.0 9.3 4.5 6.6 9.2 1.9 1.3

Neutral detergent fiber 34.8 34.8 34.8 45.0 45.0 45.0 66.4 46.7

Acid detergent fiber 28.3 28.3 28.3 39.0 39.0 39.0 58.1 36.5

Acid detergent lignin 5.2 5.2 5.2 6.1 6.1 6.1 8.9 6.8

Metabolizable energy, MJ/kg DM 8.5a 9.7a 10.5a 8.0a 8.8a 9.9a 6.9b 7.3b

Hydrogen cyanide, mg/kg DM 12.3 12.0 11.6 17.4 17.0 16.9 10.5 –

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feed, CEP, and rice straw were calculated according to NRC(2000) and Menke et al. (1979). Hydrogen cyanide (HCN)was analyzed by colorimetric method of Indira and Sinha(1969).

Statistical analysis

All data obtained from the experiment were subjected toanalysis of variance (ANOVA) for 2×3 factorial arrangementsusing PROC GLM of the Statistical Analysis SystemsInstitute (SAS 1998). The CEP levels, CPO levels, and aninteraction of CEP×CPO were included in the statisticalmodel. The values represented the means and standarderror of the means. The differences among means in eachexperimental group were compared by Duncan's newmultiplerange test (Steel and Torrie 1980). Significance was declaredat P≤0.01.

Results

Chemical composition

Feed ingredients and chemical composition of experimentaldiets are shown in Tables 1 and 2. The DM, CP, and ADLcontents were similar among groups. Concentrate diets ofLCEP groups had OM higher than HCEP groups. However,concentrate diet in HCEP groups showed higher levels ofNDF, ADF, and ADL than LCEP groups. Ether extract andME increased with increasing levels of CPO in the diets,whereas HCN decreased.

Intake and digestibility

The effects of supplementation of CEP and CPO in cattle onfeed intake and nutrient intake were presented in Tables 3 and

Table 3 Feed intake of cassavabioethanol by-product and crudepalm oil by yearling heifers

Means in the same row with dif-ferent lowercase letters differ(P<0.05)

CEP cassava bioethanol by-prod-uct, LCEP low cassava bioethanolby-product, HCEP high cassavabioethanol by-product, CPOcrude palm oil, Int. interaction,SEM standard error of means, nsno significant difference

*P<0.05; **P<0.01

Items LCEP HCEP SEM Significance

CPO, % 0 2 4 0 2 4 CEP CPO Int.

Roughage intake, kg of dry matter

kg/d 1.7 1.3 1.5 1.6 1.5 1.4 0.07 ns ns ns

%BW 1.0a 0.8b 0.9b 0.9a 0.9b 0.8b 0.03 ns * ns

g/kgBW0.75 36.6 28.7 33.1 33.7 31.8 29.6 0.97 ns ns ns

Concentrate intake, kg of dry matter

kg/d 2.5 2.4 1.9 2.5 2.5 2.4 0.12 ns ns ns

%BW 1.5a 1.4a 1.2b 1.5a 1.5a 1.4b 0.03 ns ** ns

g/kgBW0.75 54.1a 50.8a 41.3b 53.4a 53.4a 50.7b 1.24 ns * ns

Total feed intake, kg of dry matter

kg/d 4.2 3.7 3.4 4.1 4.0 3.8 0.17 ns ns ns

%BW 2.5a 2.2b 2.1b 2.4a 2.4b 2.2b 0.04 ns ** ns

g/kgBW0.75 90.7a 79.5ab 74.4b 87.1a 85.2ab 80.3b 1.89 ns * ns

Table 4 Nutrient intake of cassava bioethanol by-product and crude palm oil by yearling heifers

Items LCEP HCEP SEM Significance

CPO, % 0 2 4 0 2 4 CEP CPO Int.

Dry matter 4.2 3.7 3.4 4.0 4.0 3.8 0.17 ns ns ns

Organic matter 3.6 3.2 2.9 3.4 3.3 3.2 0.15 ns ns ns

Crude protein 0.5 0.4 0.4 0.4 0.4 0.4 0.02 ns ns ns

Ether extract 0.1b 0.2a 0.2a 0.1b 0.2a 0.2a 0.01 ns ** ns

Neutral detergent fiber 1.7B 1.5B 1.4B 1.9A 1.8A 1.7A 0.07 * ns ns

Acid detergent fiber 1.3B 1.2B 1.1B 1.5A 1.5A 1.4A 0.06 ** ns ns

Means in the same row with different letters differ (P<0.05), effect of CEP and CPO

CEP cassava bioethanol by-product, LCEP low cassava bioethanol by-product, HCEP high cassava bioethanol by-product, CPO crude palm oil, Int.interaction, SEM standard error of means, ns no significant difference

*P<0.05; **P<0.01

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4. The results showed that cattle-fed CEP and CPO in con-centrate diets had no interaction across all parameters.Different levels of CEP or CPO had no effect on feed intake(kilogram per day). However, roughage intake, concentrateintake, and total feed intake decreased with higher levels ofCPO in both LCEP and HCEP groups in terms of body weightper day (%BW/d, P<0.01) and metabolic body weight(g/kgBW0.75/d, P<0.05).

No statistical difference for combination of CEP andCPO were found in terms of nutrient intake. Intakes ofdry matter, organic matter, and crude protein were sim-ilar among groups, and EE intake increased with higherlevels of CPO (P<0.01). Nevertheless, intakes of NDF(P<0.05) and ADF (P<0.01) were higher for HCEPthan LCEP.

The effects of CEP and CPO in heifers on digestibilitycoefficients are shown in Table 5. An interaction for digest-ibility of dry matter, organic matter, ether extract, NDF, andADF was observed. Apparent digestibility of LCEP4 grouphad DM (P<0.001), OM (P<0.001), and CP (P<0.01) higherthan other groups, whereas digestibility of fat (P<0.001) and

fiber (P<0.001) were the highest in HCEP4 and HCEP2groups, respectively.

Growth performance

The growth performances of the heifers fed CEP and CPO areshowed in Table 6. There were no significant difference in thefinal body weight (FBW), weight gain (WG), average dailygain (ADG), and FCR among supplemented heifers.

Discussion

Intake and digestibility

Average dry matter intake (Table 4) ranged from 3.4 to 4.2 kgDM/day and was not influenced by by-product and fat sup-plementation (P>0.05).Many researchers had evaluated grad-ed levels of by-products such as corn, wheat, and barley inanimal diets, but they obtained different results. In the currentstudy, no difference on dry matter intake was found when

Table 5 Apparent digestibility coefficients of cassava bioethanol by-product and crude palm oil by yearling heifers

Items LCEP HCEP SEM Significance

CPO, % 0 2 4 0 2 4 CEP CPO Int.

Dry matter 50.8b 52.8a 52.8a 48.8d 48.9c 49.4c 0.08 *** *** ***

Organic matter 56.0c 58.6a 58.6a 54.3d 54.3d 57.7b 0.08 *** *** ***

Crude protein 60.7c 65.2b 68.3a 56.2e 58.5d 60.0cd 0.35 *** *** *

Ether extract 82.2d 86.6c 88.8b 78.3e 87.4c 90.5a 0.14 * *** ***

Neutral detergent fiber 27.0e 26.2f 28.3d 30.0c 33.5a 32.2b 0.06 *** *** ***

Acid detergent fiber 14.0f 14.9e 18.8d 23.7c 28.2a 24.9b 0.02 *** *** ***

Means in the same row with different lowercase letters differ (P<0.05)

CEP cassava bioethanol by-product, LCEP low cassava bioethanol by-product, HCEP high cassava bioethanol by-product, CPO crude palm oil, Int.interaction, SEM standard error of means

*P<0.05; ***P<0.001

Table 6 Growth performance of cassava bioethanol by-product and crude palm oil by yearling heifers

Items LCEP HCEP SEM Significance

CPO, % 0 2 4 0 2 4 CEP CPO Int.

Initial body weight, kg 126.5 131.1 131.0 131.1 131.9 130.9 5.39 ns ns ns

Final body weight, kg 205.8 203.5 196.5 203.7 202.3 208.0 8.32 ns ns ns

Weight gain, kg 79.3 72.3 65.5 72.6 70.7 77.1 3.84 ns ns ns

Average daily gain, kg 0.5 0.5 0.4 0.5 0.4 0.5 0.03 ns ns ns

Feed conversion ratio 8.5 8.4 8.5 8.9 9.19 7.9 0.32 ns ns ns

CEP cassava bioethanol by-product, LCEP low cassava bioethanol by-product, HCEP high cassava bioethanol by-product, CPO crude palm oil, Int.interaction, SEM standard error of means, ns no significant difference

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supplementing with either 15 or 30 % CEP. This is similar toresults reported by Gibb et al. (2008) who found that DMintake was not observed when replacing 20 or 40 % of thebarley with DDGS. However, increasing level of DDGS ( 0,16.7, 33.3, and 50 % of DM) in diets fed to beef steers did notaffect DM intake, but linearly decreased digestion for DM,NDF, ADF, and starch (Salim et al. 2012). Steers-fed diet with0, 10, 20, and 30 % DDGS showed that DM and NDF intakesincreased with increasing levels of DDGS but OM and energydigestion linearly decreased (Carrasco et al. 2013). However,Walter et al. (2012) reported that feeding 20 or 40 % of wheatDDGS reduced DM and OM intake. These results are similarto other trials (Allen 2000; González et al. 2014) that nutrientcomposition in diets influence nutrient intake, digestion, anddigestibility.

Feed intake (kilogram per day) was not affected by fatinclusion (P>0.05), similar to research reported by Choiet al. (2013) that steers-fed diet with 3 % palm oil or soybeanoil had no effect on feed intake. However, our study revealedthat fat supplementation linearly decreased concentrate intakeas %BW and g/kgBW0.75 from 3.5 to 14.6 % and 3.1 to14.5 %, respectively. Similarly, supplemental rice bran oil(Lunsin et al. 2012) or SFO (Mapato et al. 2010) at 6 % ofcows’ diet reduced feed intake (19 and 14%, respectively) andsome nutrient digestibility. Moreover, higher levels of fatlinearly decreased OM, NDF, and fat digestion (Plascenciaet al. 2003). In addition, Allen (2000) reported that 6 % SFOin the diet significantly decreased DMI because fat supple-mentation increases the energy density of the diet, and it maycause decreased feed intake. This concept is supported byNRC (1987) that feed intakes are based on and controlled bygut fill and energy demand of animal.

Growth performance

Heifer diets containing combinations of CEP and CPO did notinfluence growth performance. Similar results were reportedby Gibb et al. (2008) who fed 20 or 40 % barley DDGS thatdid not affect ADG and gain:feed (G:F), and Wood et al.(2011) informed that corn-DDGS can be used up to 20 % ofthe diet without adverse effect on performance. Nevertheless,ADG and G:F of growing beef steers that were fed with 10.5or 17.5 % DDGS (Eun et al. 2009) were improved. On theother hand, steer fed with 3% palm oil did not affect ADG andG:F, but those fed with 3 % soybean oil decreased the animalperformance (Choi et al. 2013). A similar result by Gonzálezet al. (2014) said that cattle-fed diet with 4.5 % fat fromlinseed, sunflower, and soybean had no impact on animalperformance. However, some studies found that feeding fatat levels up to 8 % of the barley-based finishing diet improvedweight gain (Zinn 1989). These different responses on animalperformance are likely caused by differences in energy

density, ingredient composition of the basal diet, and eatingbehavior (NRC 1987).

Conclusion

The CEP can be used up to 30 % in the diet. Adding CPO inthe by-product-based diet had no effect on feed intake andperformance. However, increasing levels of CPO reducedfeed intake of cattle (both % of BW and metabolic bodyweight, g/kgBW0.75). Therefore, CEP can be used in cattlefeed with or without additional fat inclusion.

Acknowledgments The authors would like to express their most sin-cere thanks to the financial support from the Thailand Research Fundthrough the Royal Golden Jubilee Ph. D. Program (Grant No. PHD/0169/2551). The Increased Production Efficiency and Meat Quality of NativeBeef and Buffalo Research Group, Khon Kaen University, is acknowl-edged for some specific advice.

Conflict of interest The authors declare that they have no conflict ofinterest.

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