Nutritive Value Assessment of the Alternative Feed Resources by Gas Production and Rumen Fermentation In vitro

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1 Reserh Journl of Agriulture nd Biologil Sienes 1(2): , , INSInet Pubition Nutritive Vlue Assessment of the Alterntive Feed Resoures by Gs Prodution nd Rumen Fermenttion In vitro S.M.A. Sllm Animl Prodution Deprtment, Fulty of Agriulture, Alexndri University, Alexndri, El-Shtby, Egypt. Abstrt: In vitro gs prodution nd rumen fermenttion hrteristis were mesured to evlute some lterntive feed resoures e.g. rie strw, tropil shrubs (Artiplex semibt, Artiplex hlimus, Leuen), Artihoke leves nd Artihoke stems in omprison with berseem hy. A gs test tehnique ws performed using fistulted sheep rumen fluid. Cumultive gs prodution ws reorded t 3, 6, 9, 12, 24, 48, 72 nd 96 h -(t-l) of inubtion nd gs prodution onstnts (b,, L) were desribed using the eqution Gs(t)= b(1-exp ). Ammoni-N nd voltile ftty ids (VFA) onentrtion were determined t 0,1,3 nd 6 hr. of inubtion. The NDF, ADF nd ADL were signifintly different mong roughges used in this study. The rie strw ontin highest level of NDF nd ADF, while Leuen ontin the highest level of ADL. The lowest fiber onstitutes were observed in rtihoke leves or stems. The mximum gs volume (b) ws highest for Artihoke stems followed by rtihoke leves, bereem hy, rie strw, Atriplex semibt nd Leuen nd lowest for Atriplex hlimus. The mximum rte of gs prodution () ws highest for both rtihoke stems nd leves nd berseem hy nd lowest for rie strw. The fermenttion end produts either mmoni-n or totl voltile ftty ids vried signifintly mong the roughges. There were signifint (P<0.05) differenes between forges in terms of metbolizble energy (ME), net energy (NE) (MJ/kg DM) nd orgni mtter digestibility (OMD). The orgni mtter digestibility vlues rnged from % nd the highest vlue ws tht of rtihoke stems nd the lowest vlue ws tht of rie strw. The leves or stems of rtihoke showed the highest (P<0.05) vlues for ME, NE nd OMD thn ll of the other roughges used in this study. All tropil shrub plnts nd rie strw hd lower in vitro fermenttion hrteristis, umultive gs prodution nd kinetis prmeters thn berseem hy used s stndrd hy. The in vitro gs prodution tehnique n be used to determine the nutritive vlue of the roughges nd to identify differenes mong their potentil digestibility nd energy ontents. This study onluded tht rtihoke ws onsidered s high qulity roughge in omprison with berseem hy ording to nutritive qulity nd gs prodution prmeters. Key word: Nutritive vlue, roughges, gs prodution, fermenttion, in vitro INTRODUCTION [18] ost fodder for nimls. Use of these forges in niml diets ould prtiipte in reduing the shortge of niml The ppelltion; Alterntive feed resoures; hs feed resoures nd subsequently inrese milk nd met beome ommonly used to design those lol feeds, prodution in Egypt. The knowledge bout their potentil whih ould reple prtilly or totlly onventionl feeding vlue is insuffiient. The nutrient omposition of feedstuffs either grss forges or onentrte feeds feeds is ommonly determined primrily by hemil without reduing livestok performne but should nlyses. However, this does not provide suffiient derese the feeding ost. informtion to determine the feed s true nutritive vlue. Tropil plnts nd griulturl by produts The effiieny by whih n niml utilizes feed nutrients represent n importnt fodder reserve for livestoks in hs signifint impt on its produtive performne hrsh onditions tht n be used by grzing ruminnt in nd wste prodution. In the serh to improve nd periods of feed srity. Leuen leuoephl is optimize this trophi hin, it is therefore ruil to leguminous plnt nd it hs high ontent of protein, further develop methods to evlute fibrous feeds, so tht [1] energy, rotens nd minerls. Atriplex speies ontin ruminnt prodution n be mximized. Therefore, in vitro moderte level of rude protein, high level of fiber methods of feed evlution hve numerous dvntges frtions nd sh. These forges should be slt tolernt over in vivo methods. They re less expensive, less timeor / nd drought resistnt to be dptble for propgtion onsuming nd llow inubtion to be mintined more under rid onditions nd n onsiderbly provide low- preisely thn in vivo. In ddition, in vitro tehniques Corresponding Author: S.M.A. Sllm, Animl Prodution Deprtment, Fulty of Agriulture, Alexndri University, Alexndri, El-Shtby, Egypt. 200

2 Res. J. Agri. & Biol. Si. 1(2): , 2005 Tble 1: Chemil omposition nd fiber frtiontions of berseem hy, rie strw, Atriplex semibt, Artiplex hlimus, Leuen, Artihoke leves nd Artihoke stems Item Hy Rie strw Artiplex semibt Artiplex hlimus Leuen Artihoke leves Artihoke stems Ash Orgni mtter Crude protein Crude fiber Ether extrt Nitrogen free extrt Fiber frtiontion (%) NDF ADF ADL Cellulose Hemiellulose utilize smll mounts of test feeds mking them pplible simplified nd improved. The kinetis of gs prodution to sreening feeds tht re not vilble in suffiient during ruminl fermenttion my provide vluble quntity for in vivo experiments. The in vitro methods of informtion bout feeds tht n be used to formulte [41] Tilley nd Terry, in so method of Mehrez nd rtions nd model niml responses. [30] [25] Ørskov, nd enzymti method of Jones nd Hywrd Menke nd Steingss reported strong orreltion hve ll been widely used to predit digestibility of feeds, between metbolizble energy (ME) vlues mesured in nd used s seletion tool for sreening feeds for vivo nd predited from 24 h in vitro gs prodution nd nutritionl qulity. hemil omposition of feeds. The in vitro gs The in vitro gs prodution system helps to better prodution method hs lso been widely used to evlute [15] quntify nutrient utiliztion, nd its ury in desribing the energy vlue of severl lsses of feeds, prtiulrly [28] [21] digestibility in nimls hs been vlidted in numerous strws, gro-industril by-produts, ompound [2] [24] experiments. Animl experiments will ontinue to dd feeds nd vrious tropil feeds. The min objetive informtion to our understnding of nutrient metbolism. of this study is ssessing the nutritive vlue of tropil However, where pplible the in vitro gs prodution shrubs (Artiplex semibt, Artiplex hlimus, Leuen system n be used to predit niml performne t leuoephl), Artihoke leves, Artihoke stems, rie muh lower ost. Bsed on the strong reltionship strw in omprison with berseem hy by hemil between mesured digestibility nd tht predited from nlysis, rumen fermenttion hrteristis nd gs gs prodution, regression equtions hve been prodution tehnique in vitro. developed nd the method hs been stndrdized. The ssoition between rumen fermenttion nd gs MATERIALS AND METHODS prodution hs long been known, in n erly ttempt in 1939 ws tried to reord the gs prodution diretly vi Feedstuffs: Rie strw, Artiplex semibt, Artiplex the rumen nnul in sheep, the tehnique ws too hlimus, Leuen leuoephl, Artihoke leves, [9] diffiult to exeute nd of poor reproduibility. In 1974 Artihoke stems (Cynr solymus) nd berseem hy [40] Menke nd Ehrensvärd (ited by Theodorou et l. ) were ground in mills to pss 1 mm sieve prior to hemil studying the stoihiometry of rumen fermenttion with nlyses, in vitro gs prodution mesurements nd syringe losed system notied very reproduible gs rumen fermenttion. The hemil omposition of the prodution dt when the sme substrte ws inubted roughges used for in vitro gs prodution nd rumen in the sme quntity in different runs. The min fermenttion re presented in Tble 1. Only one smple of innovtion in suh method ws tht the gs prodution is eh feed ws utilized, s feeds were seleted to reorded rther thn degrdtion. The sme postulte represent rnge in fermentbility, rther thn to ontinues until tody, even when the method hd been tegorize the feeds 201

3 Res. J. Agri. & Biol. Si. 1(2): , 2005 Chemil Anlyses: All feedstuff smples were nlyzed Energy estimtion: The energy vlue of forges n be [4] ording to AOAC, for rude protein (CP), Crude ft lulted from the mount of gs produed t 24 h of (CF), sh, Nitrogen free extrt (NFE), orgni mtter inubtion with supplementry nlyses of rude protein, (OM), rude fiber. Neutrl detergent fiber(ndf), id sh nd rude ft. This pproh ws developed by the detergent fiber (ADF), id detergent lignin (ADL), reserh group in Hohenheim (Germny) nd is bsed ellulose nd hemiellulose were determined ording to [32] upon extensive in vitro inubtion of forges, [43] Vn Soest et l. Menke nd Steingss. in vitro gs prodution nd rumen fermenttion: in vitro ME(MJ /Kg DM) = Gp CP gs prodution ws undertken ording to the proedure desribed by Menke nd Steingss. Buffer OMD (%)= Gp CP XA nd minerl solution re prepred nd pled in wter bth t 39 C under ontinuous flushing with CO 2. Rumen fluid is olleted from fistulted sheep fed on berseem hy nd ommeril onentrte mixture diet into pre-wrmed thermos flsk. The rumen fluid is filtered nd flushed with CO 2, nd the mixed nd CO 2 flushed rumen fluid is dded to the buffered minerl solution (1:2 v/v), whih is mintined in wter bth t 39 C, nd ombined. Smples (200 ± 10mg) of the ir-dry feedstuffs were urtely weighted into syringe fitted with plungers. Buffered rumen fluid (30 ml) is pipetted into eh syringe, ontining the feed smples, nd the syringes re [6] immeditely pled into the wter bth t 39 C. Three syringes with only buffered rumen fluid re inubted nd onsidered s the blnk. The syringes re gently shken every 2 h, nd the inubtion terminted fter reording the 96 h gs volume. The gs prodution ws reorded fter 3, 6, 9, 12, 24, 48, 72, nd 96h of inubtion. Totl gs vlues re orreted for the blnk inubtion, nd reported gs vlues re expressed per 200mg of DM. Another two bottles ontining 300mg feedstuffs smples nd 45ml Buffered rumen fluid were inubted for the determintion voltile ftty ids (VFA) nd mmoni onentrtion t 0, 1, 3 nd 6h from inubtion. Ammoni nd VFA onentrtion were determined ording to Gips nd Wibbens- [16] [46] Alberts nd Wrner respetively. Cumultive gs ws expressed s milliliter of gs produed per 200mg of dry mtter nd orreted for blnks. Berseem hy ws used s stndrd hy. Cumultive gs prodution GAS(t) t time t ws fitted to the modified exponentil model [11] Gs(t)= b(1-exp -(t-l) ), with the exlusion of the interept. Where b = The gs prodution from the insoluble frtion (ml) = The gs prodution rte onstnt for the insoluble frtion (b) t = Inubtion time(h) L = Lg time (h) Where ME is the metbolizble energy OMD is orgni mtter digestibility Gp is 24 h net gs prodution (ml/200dm) CP is rude protein (% of DM) XA is sh (%of DM) NE(Ml/lb) = (2.2 + (0.0272*Gs) + (0.057*CP) + (0.149*CF)) /14.64 Where Gs is 24 h net gs prodution (ml/gdm) CP is rude protein (%of DM) CF id rude ft (%of DM) Then net energy unit onverted to be MJ /Kg DM. Sttistil nlyses: Dt were subjeted to nlysis of vrine (ANOVA) using the Generl Liner Model. Signifint differenes between individul mens were identified using lest signifine differene (LSD) [36] multiple rnge test. RESULTS AND DISCUSSION Chemil omposition nd gs prodution: The hemil omposition nd fiber frtiontions of rie strw, Atriplex semibt, Atriplex hlimus, Leuen, Artihoke leves, Artihoke stems nd berseem hy re presented in Tble 1. Forges hd vrible orgni mtter ontent with lowest in A. hlimus nd semibt nd highest in rtihoke nd Lueen. The rude protein ontent vried from 4.85% in rie strw to % in Leuen. The ether extrt ontent of forges ws lowest in rie strw nd it does not differ signifintly mong other forges. The fiber frtions differ signifintly mong forges. The highest vlue for NDF, ADF, ADL, ellulose nd hemiellulose were observed in rie strw nd the lowest vlues in rtihoke stems. Leuen hd higher ADL ontent nd lower ellulose ontent thn other roughges. Artihoke either leves or stems hd lower ADL ontent. 202

4 Res. J. Agri. & Biol. Si. 1(2): , 2005 Figure 1 showed the umultive gs prodution followed by smple of berseem hy nd the lowest ws profiles, orreted for blnk fermenttion, of the seven obtined by the smple from A.hlimus. This is due to different roughge smples tht were inubted in high ontent of the rtihoke from NFE whih, hve buffered rumen fluid from sheep fed the rtion with positive orreltion with gs prodution. On the other berseem hy nd onentrte. There ws fst initil gs hnd, Cell wll ontent (NDF nd ADF) were negtively prodution, without lg time, fter whih gs prodution orrelted with gs prodution t ll inubtion times nd diminished little but styed t high level. After 15 to estimted prmeters. This my tend to redue the 24 h of inubtion, gs prodution deresed further but mirobil tivity through inresing the dverse did not stop fully. Inubtion of feedstuff with buffered environmentl onditions s inubtion time progress. rumen fluid in vitro, the rbohydrtes re fermented to Also, The reltively high level of ADL in rie strw nd short hin ftty ids (SCFA), gses minly CO 2 nd Leuen s shown in Tble 1 explins in prt the limited CH 4 nd mirobil ells. Gs prodution is bsilly the in vitro degrdtion nd therefore the lower mount of result of fermenttion of rbohydrtes to ette, gs produed. [47,5,8] propionte nd butyrte. Gs prodution from protein Gs prodution n be regrded s n inditor of fermenttion is reltively smll s ompred to rbohydrte degrdtion nd the low gs prodution in rbohydrte fermenttion while, ontribution of ft to Atriplex re explined by ondensed tnnin s binding to [47] gs prodution is negligible. the rbohydrte nd then by the inhibition of enzymes or The fst initil gs prodution ws highly signifint [17] miroorgnisms, omplexing with lignoellulose, nd (P<0.01) in Artihoke stems in omprison with other preventing the mirobil digestion. Tropil feeds ontin roughges. The highest umultive gs prodution ws onsiderble mounts of phenoli ompounds tht observed in rtihoke either stems or leves whih, ws redued in vitro gs prodution. The orreltion between 203

5 Res. J. Agri. & Biol. Si. 1(2): , 2005 the hnge in gs prodution in the presene of tnnin from rie strw, A.semibt nd Leuen. There re binding gent nd phenoli ontents of browses ws similrity between observed gs prodution nd predited [22] onsistent with those of Khzl et l nd Toler gs prodution by exponentil model (dt not shown). [42] et l. However, sine gs prodution on inubtion of The gs yield of rtihoke stems is higher thn rtihoke feeds in buffered rumen fluid is ssoited with feed leves. There is no signifint differene between rie fermenttion, the low gs prodution from rie strw, strw, A.hlimus, A.semibt nd Leuen in Artiplex semibt, Artiplex hlimus, Leuen, ould be umultive gs prodution. relted to low feeding vlue of these feeds. In ddition, The lg time is (time from inubtion to strt of gs Leuen ontins toxin ompounds eg. mimosine whih, prodution) very importnt digestibility prmeters. The hs negtive orreltion with gs prodution. The shorter lg time period for Leuen ould be due to high vrition in the in vitro gs prodution on inubtion of whole struture rbohydrtes ontent. Sine the these roughges were explined by the differenes in totl utiliztion of roughges is lrgely dependent upon VFA prodution s observed in Fig. 3, whih minly mirobil degrdtion within the rumen, desription of omes from rbohydrte fermenttion. These results re roughges in terms of their degrdtion hrteristis [20] onsistent with the finding of Kmlk et l nd would provide useful bsis for their evlution [3] Abdulrzk et l. (nonymous). Kinetis of fermenttion of feedstuffs n Vlues for the estimted prmeters obtined from the be determined from fermenttive gs nd the gs relesed kinetis exponentil model nd umultive gs prodution from buffering of the SCFAs. Kinetis of gs prodution t 24 nd 48 hr (GAS24 nd GAS48) re given in Tble2. is dependent on the reltive proportions of soluble, GAS 24 nd GAS 48 rnged from 25.7to nd from insoluble prtiles of the feed. Mthemtil desriptions to 54.8 ml/200mg DM, respetively. Estimted lg of gs prodution profiles llows nlysis of dt, vried from 3.26h in Leuen to 0.32h in A.semibt. evlution of substrte nd medi-relted differenes, nd Estimted onstnt rte of gs prodution () differ fermentbility of soluble nd slowly fermentble signifintly between roughges. The highest rte of gs omponents of feeds. Vrious models hve been used to prodution ws observed with rtihoke stems followed [33] desribe gs prodution profiles. The exponentil model by rtihoke leves nd berseem hy. The lowest rte ws is widely used in ruminnt feed evlution to desribe found with A.hlimus whih, did not differ signifintly degrdtion kinetis s mesured with the nylon bg 204

6 Res. J. Agri. & Biol. Si. 1(2): , 2005 Tble 2: Aumultive gs prodution (Gs24h, Gs 48h) nd estimted kineti prmeters for vriety of roughges inubted with rumen fluid in vitro. Gs 24h (ml/200mgdm) Gs48h (ml/200mgdm) b (ml/200mgdm) (perentge of b per hour) Lg(h) Hy b b Rie strw b b A.semibt b b A.hlimus b Leuen b b Artihokeleves b b Artihoke stems d b -1.34, b nd mens within sme olumn with differing supersript re signifintly different (P<0.05). Tble 3: Metbolizble energy (ME MJ/KgDM), net energy (NE MJ/KgDM) nd orgni mtter digestibility (OMD) predition for different roughges in vitro. ME MJ/KgDM NE MJ/kgDM OMD % Hy b 7.94 b 5.19 b Rie strw Artiplex semibt Artiplex hlimus Leuen Artihoke leves 8.56b b 5.59 b Artihoke stems , b nd mens within sme olumn with differing supersript re signifintly different (P<0.05). 205

7 Res. J. Agri. & Biol. Si. 1(2): , 2005 tehnique, but the model hs lso been used to desribe widely being prtiulrly high in rtihoke stems, leves kinetis of gs prodution dt s desribing by Blummel nd berseem hy. While the other four forges hd [7] [37] [23] et l, Siw et l nd Khzl et l. signifintly lower vlues of ME nd NE. The dt showed tht there ws no signifint differene mong Rumen fermenttion: NH3-N onentrtion (mg/100ml rie strw, A. semibt, A. hlimus, Leuen, or Rumen fluid) profile t 0, 1, 3 nd 6 hr of inubtion berseem hy. The rtihoke stems nd leves hd the in vitro for rie strw, A. semibt, A. hlimus, higher ontent of ME nd NE in omprison with Leuen, Artihoke leves, Artihoke stem nd berseem breseem.. There ws positive orreltion between hy re presented in Tble 3. The highest NH3-N metbolizble energy lulted from in vitro gs onentrtion ws observed fter 3hr of inubtion prodution together with CP nd ft ontent with prtiulrly in rtihoke nd berseem hy. The lowest metbolizble energy vlue of onventionl feeds NH3-N onentrtion ws observed in rie strw nd mesured in vivo. signifintly (P<0.05) different from ll of the other The orgni mtter digestibility (OMD)% ws higher roughges. There is no signifint (P<0.05) differene (P<0.05) in rtihoke stems nd leves nd lowest in rie between rtihoke either leves or stems nd berseem hy strw. The OMD differs signifintly mong rtihoke in NH3-N onentrtion. While, the mmoni leves nd stems nd berseem hy in omprison with rie onentrtion in rtihoke leves or stems nd berseem strw, A.hlimus, A.semibt, nd Leuen. The OMD hy is signifintly (P<0.05) higher thn rie strw, of rtihoke stems is signifintly higher thn berseem A. semibt, A. hlimus or Leuen. This my be due hy but it ws not signifint with rtihoke leves. There to high N solubility in berseem hy nd rtihoke. The re no signifint differenes between berseem hy, rie profile of NH3-N onentrtion is similr nd there is no strw, A.hlimus, A.semibt, or Leuen in OMD. signifint differene (P<0.05) mong A. semibt, However, the tropil feeds ontined onsiderble A. hlimus or Leuen. The redution of NH3-N mounts of seondry plnt metbolites, prtiulrly onentrtion in Atriplex speies my be ttributed to tnnins whih, is ssoited with redution in nti-nutritionl ftors like ondensed tnnins whih form [38,45,14] OMD. Using the in vitro gs mesurement nd omplex ompound with protein whih dversely ffet hemil omposition in multiple regression eqution, [34] [32] [29] [44] N digestion. Menke et l, MLeod nd Minson nd Vn Soest Totl voltile ftty ids (TVFA, mm) onentrtion found high preision in predition of in vivo OMD. This profile t 0, 1, 3 nd 6 hr of inubtion in vitro for rie group further used orreltive pproh to predit the strw, A. semibt, A. hlimus, Leuen, Artihoke ME ontent of feed by in vitro gs volume mesurements leves, Artihoke stem nd berseem hy re presented in nd hemil onstituents nd onluded tht the Figure 2. VFA produed vried signifintly (P<0.05) predition of ME is more urte when bsed on gs nd between rie strw nd ll of other roughges. There is no hemil onstituents mesurements s ompred to signifint differene in VFA prodution mong lultions bsed on hemil onstituents only. These A. semibt, A. hlimus or Leuen but the VFA [39] studies hve been reviewed by Steingss nd Menke onentrtion in Artihoke leves or stems nd berseem nd Menke nd Steingss. Other workers Chenost [10] [13] [27] hy ws signifintly higher (P<0.05) in omprison with et l, Fernndez-River, Mheboeuf et l nd A. semibt, A. hlimus or Leuen. The vrition in [35] Romney et l hve lso reported signifint orreltion VFA prodution mong the roughges used in this study between in vitro gs mesurement nd in vivo my be due to the differenes in mount, nture nd digestibility. Inlusion of rude protein ontent to gs fermentbility of rbohydrtes vilble to volume improved preision of predition of in vivo OMD [12] [19] [10] [26] miroorgnisms. Done et l nd Kmlk et l found Chenost et l, Mheboeuf nd Jestin, Mheboeuf signifint orreltion between SCFA nd gs [27] et l. There ws positive orreltion between ME prodution. lulted from in vitro gs prodution together with CP nd ft ontent with ME vlue of onventionl feeds Energy ontents nd orgni mtter digestibility: The mesured in vivo. predited metbolizble energy (ME, MJ/kgDM), net In onlusion, there re onsiderble differenes in energy(ne, MJ/kgDM) nd orgni mtter digestibility the fermentbility of rbohydrtes between different (OMD) from gs prodution for rie strw, A. semibt, roughges. This study suggested tht rtihoke hve A. hlimus, Leuen, Artihoke leves, Artihoke stems potentil fermenttion effiieny better thn berseem hy nd berseem hy re presented in Tble 3. The predited nd therefore, rtihoke ould be inorported in feed ME nd NE profile re similr in seven forges nd vried mixtures to reple onventionl roughge soures 206

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