DINH DUONG VA THLTC AN CHAN NUOI
ANH Hl/ONG CUA XO TRUNG TINH TRONG THU'C AN HON HOP DEN TIEU THU VA TIEU HOA DU'ONG CHAT THU'C AN
TREN BO CAI BRAHMAN TAI TINH AN GIANG
Nguyen Binh Tnrong'*, Nguyen Trdn Phudc Chieh\ Hd Ho Nggc Hieu^ vd Nguyen Cong Kba- N g a y n h a n bai b a o : 21/10/2018 - N g a y n h a n bai p h a n bien: 20/10/2018
N g a y bai b a o d u o c cha'p n h a n d a n g : 22/11/2018 T O M T A T
Ngbien cuu cac miic xo trung tinh (NDF) trong thuc an hdn h o p (TAHH) den tieu thu va tieu hoa dudng chat thuc an (TA) tren bd cai Brahman tai tinh An Giang dugc thuc hien tai Trung tam Cong nghe sinh hpc linh An Giang. Thi nghiem (TN) d u o c bd'tri theo mo hinh 6 vuong Latin, thuc hien lrong 14 ngay tren bd cai Brahman cd khoi lugng trung binh (KL) la 350±ll,5kg Ba nghiem thuc (NT) la 3 muc NDF cua TAHH: 16% NDF (NDF16), 24% NDF (NDF24) va 32% NDF (NDF32), TAHH cho an c o d j n h 0,5% KL va co Voi cho an tu do, Ke't qua cho tha'y, muc NDF trong TAHH tang 16-32% thi NDF tieu thu giam tii 3,99 xud'ng 3,92 kg/con/ngay nen NDF/DM tang tii' 56,4 len 61,1% (P<0,05). DM/KL giira cac NT khac biet khdng cd y nghia (1,78-1,88%) n h u n g tong DM Heu thy tang dan khi NDF trong TAHH tha'p. Ty 1? tieu hoa NDF ciia TAHH khac biel khong cd y nghia giira cac NT. Muc d u o n g chat deu boa DM, OM va NDF khac biet khong cd y nghia thd'ng ke giu'a cac NT va cd xu hudng giam dan, CP giam dan 70,8-66,2% khi tang NDF ciia TAHH 16-32%. Ket qua nay the hifn khi cung cap thieu NDF tu TAHH thi bd tang tieu thu thuc an thd d e cung cap NDF cho co the dam bao dinh d u o n g cho hoat dpng sinh ly tieu hoa, muc NDF tha'p cho tieu hoa duong cha't tot ban, Vgy, tang mii'c NDF cua TAHH trong khau phan chua tim tha'y anh h u d n g de'n kha nang tieu thv va tieu hda d u o n g chat thiic an tren bd cai Brahman n h u n g ty le tieu hda d u o n g cha't cd xu hudng giam. Miic NDF 16% cua TAHH cho ke't qua toi iru,
Tir khoa: So Brahman, xo trung finh, thuv an hon hgp, tieu hoa dudng chiit.
ABSTRACT
Effects of different neutral detergent fiber levels of concentrate in diets on feed intake and nutrient digestibility of Brahman female cattle in An Giang province A study of effects of different neutral detergent fiber (NDF) levels of concentrate in Brahman female diets on feed intake and nutrient digeshbiUties was carried out in the experimental farm of Biotechnology center of An Giang province. The experimental design was Latin Square with 3 treatments and 3 periods. Three Brahamn females with the average of body weight was 350±11,5kg were used for this experiment. Each period was 14 days including 7 day for adaptation and 7 days for sample collection. Three treatments were three levels of NDF of concentrate at 16, 24 and 32%
(DM basic) correspoding to NDF16, NDF24 and NDF32 treatments. The concentrate was fed at 0.5% body weight and Elephant grass was fed ad libitum for all experimental cattle. The results showed that by inreasing NDF levels of concentrate from 16 to 32%, NDF intakes of experimental cattle reduced from 3.99g to 3.92 kg/head/day and NDF/DM increased fi-om 56,4 to 61 1% (P<0.05).
The DM/BW values were similar among treatments being 1.78-1.88% (P>0.05), however, DM intake tended to increase for lower NDF level of concentrate in the diets. The NT)F digestibility was not si- gnificantly different among diets. The digestible DM, OM and NDF was slightiy decreased (P>0.05) by increasing NDF level of concentrate from 16% to 32% in the diets. In conclusion, the increasing of NDF levels of concentrate in the diets were not negative effects on feed and nutrient intakes but nutrient digestibilities of experimental cattle tended to decrease. The NDF level of concentrate was 16% for optimal results.
Key words: Brahman, neutral detergent fiber, concentrate, nutrient digestibility.
' Truong Dgi hgc An Giang
• Trung tam cong nghe sinh hgc tinh An Giang
• Tac gia hen he: ThS. Nguyen Binh Truong - Truong Dai hgc An Giang, So' 18 Ung Van Khiem. TP, Long Xuyen, Tmh An Giang. Dien thogi: 0983 377 424. Email: nbtruong@agu edu.vn
I'UfTr'LA^ . , . , A ; ^A tAt: tUA
DINH DU'ONG VA THU'C ANCHANjge^
I.BATVAND^
Muc protein thd (CP) cua thiic an hon hgp (TAHH) da anh hudng de'n kha nang tieu thu va tieu bda dudng chat tren bd cai fo Brahman, muc 17% eho ke't qua tdi uu. Xo trung dnh (NDF-Neuhal Detergent Fiber) dugrc bie't den nhu mpt cha't xo ed the dupe tieu boa bdi he VI sinh vat da cd cua gia i^uc. Theo Harper va McNeill (2015), NDF quan trpng nhu mpt ngudn cua ME, mpt bp dieu khieh ho^t dpng d^ CO va can thie't de kich thieh san xua't nudc bpt, lam chat dpn cbo d^ cd qua dd tbiic dav CO bdp da cd. Lupng NDF tdng the trong khau phan an la co so bieu qua de trao ddi cac cha't xo hong khau pban an nham d?t dupe miic cha't khd (DM) tieu tbu td't nha't va su gia tang NDF trong khau phan cd the Iam tang Iupng thuan cbo duy tri ma khdng lam thay doi hieu qua TA ciia gia sue. Tren bd tbiL Iupng NDF tieu thy cd mdi tijerng quan chat cbe vdi kbdi Iupng gia sue (r=0,954), lupng DMI (rM),965) va gia trj nang lupng thuan cho sinh trudng (r==0,859) (Arelovicb va ctv, 2008). Nh4m dap ung nhu cau dinb dudng cbo bd cai Brahman va tgn dyng cac nguyen lieu san cd cua dia phuang nhu bap, ta'm, cam, bpt ea,... de phdi trpn thanh TAHH, nghien euu xac dinh miic NDF phu bpp hong TAHH cua bd eai Brahman la can thiet.
2. V A T U | U VA PHITONG P H A P N B H I E N CliTU
2.1. Vat lieu
Thi nghiem (TN) dupc tbuc hien tren 3 bd cai to Brahman cd khd'i lupng (KL) la 350±11,5kg, tai Trung tam Cdng nghe Sinh hpc tinb An Giang, ap Vinb Phude, Vinh Binh, Chau Tbanh, An Giang va Phdng thi nghiem Bd mdn Chan nudi, Trudng Dai hpc Can Tho.
2.2. Bd tri thi nghiem
Thi ngbiem dupe bd tri tbeo md binh 6 vudng Latin vdi 3 nghiem thiie (NT) \-a 3 giai doan tren bd eai Brahman. Ba NT la .\T1 gom cd \'oi + TAHH 16^,NDF (NDF16); NT2 gom cd \'"oi + TAHH 24"i,NDF (NDF24); NT3 gdm CO Voi + TAHH 32%NDF (NDF32). TAHH cho an ed dinh miie 0,5% KL eo the bd vdi edng thiie phd'i trpn the bien qua Bang 1.
Bang 1. Ty 1? thyt lieu phdi h^n thuc an hon hf^p
Chi tieu NDFlb N P I 2 £ NDTS^, Tam 3Z0 11.0 " " "DIunanh 10.0 10,0 "O-^
Bap 20,0 14,0 7,00 Thirc li?u Cam \2,0 21,0 7,00 d'S) Bptca 12,0 10,0 10,0 Xac dira 13,0 33,0 58,0 Premix 1,00 1,00 LOO Tong 100 100 1(H) Thanh DM S4,l 76,4 65,5 phan OM 92,0 90,5 92,0 dinh CP 17,2 17,0 16,9 duong NDF 16,1 24,1 31,8 t"^") ME (Kcal/kgDM) 3.002 3,141 3.432
TAHH cho 3n d muc 0,5% KL bd, duge ean bSng can dien tii Electronic Kitchen Scale (QZ161 ) loai 5kg cd sai so la lg, cho an 2 lan/
ngay vao Iuc 7 va 13b. Cd Voi eho an dupe can bang can dong bd Nhan Hda (NHS-30) logi 30kg, Thi nghipm tieu hda in vivo dupc thuc hien trong 14 ngay/giai doan: ngay 1-7 tap an, ngay 8-14 thu mau thuc an va thuc an thda, ngay 11-14 thu mau phan.
Gia tri dinh dudng thuc an, thiie an thua va phan trong TN, muc duong chat tieu thy va ty Ie tieu hda duong cha't tieu thy tren cac gia tri dinh dudng dugc xac dinh gom vat cha't khd (DM), eba't hini co (OM), dam thd (CP), xo trung ti'nh (NDF). Cac gia hi DM, OM, CP phan tich theo AOAC (1990), phan ticb NDF theo Van Soest va ctv (1991).
Ty le tieu hda tbuc hien theo phuong pbap cua MeDonal va etv (2010). Lugng khi me- tan thai ra rinh theo cdng thiic cua Mills va ctv (2003) vdi CH, (MJ/ngay)=10,03xTA thd(%)+0,87xDMI (kg/ngay)^•^,l; ME cd Voi dugc tinh theo Abate va Mayer (1997) vdi ME (MJ kg/DM)=8,ll-K),1341CP-0,]065Ash.
Nang lugng trao ddi khau phan dugc h'nh theo Bruinenberg va etv (2002): ME (MJ/
kg)=14,2xDOM+5,90xDCP 2.3. Xu ly sd lie"
So lieu thd cua TN dupc xti ly so bp tren phan mem Microsoft Office Excel 2007, sau do thuc hien bang A.NOVA tbeo md hinb GLM
KHKT Chdn nuoi so 245 - thdng 6 "dm 20i(j
DINH DU'ONG VA THlTC AN CHAN NUOI
tren phan mem Minitab Release 16.1 (Mmitab, 2010). Khi ed su khac biet giiia cac gia hi trung binh cua cac NT se dung phep thu Tukey de tim sy khac biet hmg c?p NT (P<0,05).
3.K£TOUAVATHAOLUAN
3.1. T h a n h p h a n d i n h d u o n g ciia t h u c l i e u dling t r o n g t h i n g h i e m
Ke't q u a p b a n ticb c h o tha'y n h d m T A n a n g l u p n g g o m b a p v a earn ta'm h o n g T N cd g i a hi C P lan l u g t la 9,08; 11,6 v a 8,33%; n a n g lirpng t r a o d d i t u o n g u n g la 2.912, 2.843 v a 2.928 kcal/kg D M . Ke't q u a n a y p h i i h g p v d i CP d u p e xae d j n h t r o n g n g h i e n o i u c u a V u
B i n g 2. ThAnh p h a n d u d n g chat
C h i C u a n g v a ct\- (2011) la 9,20-10,7; 13,8 v a 9,40% ( g ^ o liit) v a M E p h u h p p v d i ke't q u a ciia D i n h V a n C a i v a H o a n g Thi N g a n (2017) la 2.800-2.933 K c a l / k g D M . T h i i e a n b d s u n g p r o t e i n v d i C P d a u n a n h ly trich v a b g t ca la 43,3 v a 45,5%; C P b p t ca cao hem ke't q u a ctia D d T h i T b a n h V a n v a etv (2015) la 42,2% v a C P d a u n a n h cao h o n n g h i e n ciiu e u a N g u y e n Thi VTnh C h a u v a N g u y i n V a n T h u (2014) la 4 2 , 1 % . C d Voi h o n g T N ed gia t n D M la 21,3%, e a o b a n gia tri 17,8% c u a Le D i i e N g o a n v a ctv (2017), n h u n g g i a h i C P la 8,26% Iai t h a p b a n so v d i tac g i a la 10,7%. T h u c a n s u d y n g t r o n g T N la T A H H v a c d Voi t h e h i e n q u a B a n g 2.
cua t h u c a n t r o n g t h i n g h i e m
NFE ME (Kcal/kg DM) BSp
C a m D ^ u n i u i h Tam Bptca Xac dira Co Voi
86,1 88,6 83,9 85,5 87,0 47,5 21,3
97,9 91,5 93,5 98,0 78,5 98,7 94,5
9,08 11,6 43,3 8,33 45,5 3,34 8,26
2,89 8,80 4,96 1,26 1,12 18,6
14,7 23,9 21,8 8,20 4,82 56,0 68,8
3,38 9,41 3,50 2.43 7,41 34,6
2,14 8,5 6,53 1,99 21,5 1,31
82,5 61,7 41,7 86,0 24,5 42,2
-
2.912 2,843 3.028 2.928 3.092 4.178 2,062"
Gbi cbu: ME duac tinh Iheo Vien Chdn nuoi (2001), ' tinh theo Abate and Mayer (1997) 3.2. Lugng thlic an va dudng chat tieu thu
Bang 3. Lupng thiic an, dudng chat tieu thy va ty 1? duong chat tieu thy (kg DM) Nghiem thuc
Thuc an (kgDM)
Tong dirong cha't tieu thM (kgDM)
Tv I? dirong chat (%) TAHH Co Vol DM OM NDF CP(g) CP/DM NDF/DM DM/KLbo NDF/KLbo Thuc an tho
1,53-' 5,48 7,01 6,61 3,99 733' 10,5' 56,4=
1,88 1,07 77.7'
1,39' 5,31 6,69 6,29 3,92 686'' 10,3*
58,6' 1,79 1,05 79,1'
1,19^
5,23 6,42 6,06 3,92 644' 10,0*
61,1' 1,78 1,09 81,4"
0,000 0,398 0,113 0,109 0,812 0,039 0,025 0,004 0,254 0,288 0,006
0,004 0,101 0,105 0,096 0,078 8,994 0,036 0,153 0,031 0,013 0,144 Kha nang Ueu Ihv TAHH oia NDF16 la
1,53kg DM, cao hon so voi NDF24 la 1,39kg DM va NDF32 la 1,19kg DM (P<0,05), la do anh huong hi gia tri DM giua 3 cong thuc phoi trpn TAHH. Luyng dudng chat tieu thu cua
DM CO xu huong giam (P>0,05) khi tang muc NDF h-ong TAHH voi DM tieu thu 7,01-6,42kg DM. Ke't qua nay phu hgp vol DM/P giam dan khong CO y ngliia (1,88-1,78%) khi nang muc NDF ciia TAHH. NDF lieu thu tren NTNDF16
£-Wi'rr;.«.,
i2019 43
D I N H D U O N G \ \ T H U C AN CII ^l.^'
la 3,99kg, cao khong co v nghia so voi \ T N - DF24 va NTNDF32 cimg la 3,92kg. Ket qua nay cao hon cong bo'3,08-3,34% cua .\ia va ctv (2018) tai Trang Quoc. CP tieu thu khac biet co y nghia thong ke (P<0,05) giua cac NTNDFie, NTNDF24 va NTNDF32 voi luong deu thu la 733g, cao hon so voi 686 va 644g. Ke't qua nay cao hon cong bo hx)ng nghien cuu cua Do Van Quang va ctv (2015) tren bo Brahman la 343- 910g. Ty le thlic an tho ciia NTNDF32 la 81,4°o, cao CO y nghia so vm NTNDF24 la 79,1% va NTNDF16 la 77,7% (P<0,05) vl DM ciia TAHH giam tu 84,1 xuong 65,5"...
3,3, Ty 1^ tieu hoa va dirong chat tieu hoa thiJc an
Qua bang 4 cho tha'y khi TAHH co NDF tha'p thi bo se tang tieu thu DM tir thuc an tho dap ung nhu cau co the nen NDF tieu thu va NDF/DM CO xu hudng cao. Tv le Heu hoa DM oia NTNDF16 la 57,3%, cao hon nliung khong CO y nghia so vol .\'TNDF24 va NTNDF32 la 56,0 va 55,2%. Ke't qua nay tha'p hon cong bo cua Yuangklang va ct%' (2010) tren bo Brah- man tai Thai Lan dao dgng trong 65,5-72,2%.
Kha nang tieu hoa NDF giii-a cac NT la 46,9- 48,4% voi su khac biet kliong co y nghia thong ke. Kel qua nay phii hgp vdi gia hi thu duoc 41,9-59,7% cua Dd Van Quang va ctv (2015) nghien cu-u tren bo Brahman. Tieu hoa CP d NTNDF16 la 70,8%, cao khong cd y nghia so vdi NTNDF24 vk NTNDF32 la 67,9 va 66,2%.
Ke't qua nay cao hon gia tri 63,7-66,3% trong nghien ciiu cua Dinh Van Diing va ct\' (2014).
Tdng DM va OM tieu hda xu hudng giam dan khi tang nuic NDF ciia TAHH tit 16 len 32%
vdi gia hi DM Heu hda giam hj 4,03kg DM xud'ng 3,55kg DM va OM Keu hda hi 3,99kg DM xudng 3,52kg DM. Su khac biet nay khdng cd y nghia thd'ng ke (P>0,05). Lugng CP Heu hda cao nha't d NDF16 la 519g DM vdi su sai khac cd y nghia thd'ng ke so vdi NTNDF24 la 465g va NTNDF32 la 428g, nhung lugng NDF Heu hda cao nha't d NDF24 la 1,96kg so vdi cac NT con lai. Vay khi tang miic NDF trong TAHH cua bd chua the hien su tieu hda khac biet giira cac NT nhung ty le Heu hda cd xu hudng giam.
Bang 4. Ty le vi dirang chil lieu lio.i time an
Chi tieuDM Ty le heu Q^y h6a duone cha-.(%) NDF
CP Muc DM dumig Q^i dial
lieuh6a ^DF (kgDM) CP(g)
Nghi&m th NDFlb XDI 24
60,3 4^.9 70 8 4,03 3,99 1,91 519*
56,0 58,9 49,6 67.9 3,74 3,70 1,96 4^^'
irc NDF32
48.4
(«•,:
,^5.^
3,52 1,«
42S-
r
"OTT 0,69 (1 85 0,13 0,11 0,92 0,01
SE
__^
1,M1,67 3,13 0,09 0,08 0,08
3.4. Nang lugng tieu thy va tang khdi lupng bd thi nghiem
Nang lugng trao ddi tieu thy giua cae NT dao dpng trong khoang 14,955-16.003 Kcal/
con/ngay, n5ng lugng trao doi tinh tren khd'i Iugng cha't kbd ed xu hudng ngupc lai cao nba't d NTNDF32 la 2,329 Kcal/kgDM so vdi NTNDF24 la 2,301 Kcal/kgDM va NTNDF16 la 2.287 (P<0,05). Tlieo Danh Md (2018), nang lupng trao ddi tren bd Sind x bd dia phuong la 6.806-10.115 Kcal/con/ngay la thap hem ke't qua nay. Lupng khi CH^ eua NTNDF32 la 2.215 Kcal/con/ngay, tha'p ed y nghia thong ke so vdi NTNDF24 va NTNDF16. Lupng khi thai CH^ dao dgng trong khoang 309-345 Keal/kgDM (P<0,05). Khd'i lugng co the bd llie bSt dau TN la 355-368 kg/eon va cho tang khdi lugng d miie eao: NTNDF16 la 1.000 g/
ngay, cao hon so vdi NTNDF24 la 905 g/ngay va NTNDF32 la 786 g/ngay. Su khac biet nay khdng ed y nghia thd'ng ke. Ke't qua nay phd bgp vdi Dd Van (^uang va etv (2015) tren bd Brahman la 92,0-943 g/ngay, nbung cao han gia hi 140-260 g/ngay eua Peng va ctv (2018) va 313-706 g/ngay trong nghien cuu cua Danh Md (2018). Tu dd eho tha'y khi tang muc NDF thi miie nang lugng heu thu/con/ngay giam va lugng khi C H thai ra tba'p so vdi cac NT khac ddng thdi cbo tang trgng tot ban.
Tdm lai, nang ty le .NDF trong khau phan an ciia bd eai Brahman cho muc tit-u tbu cha't khd hr 7,01 xudng 6,03kg DM/con/ngay va lugng NDF/DM heu thu la 56,4 len 61 1 •'/. ^y JA heu hda NDF ta 46,9-49,6%. Kha nang sinh khi thai CH, tang hr 2.126 len 2.215 K c ' , ^/^g^
f^uiTT rhnn nudi so 245 - thana 6 nam "ffiKj
DINH DUONG VA THl/C AN CHAN NUOI
Bang 5. Nang Iupng tieu thu va tang khdi lugng bd thi nghiem
Ninplugng
Thay ddi khoi lupng
Chi tieu ME (Kcal/con/ngay) ME (Kcal/kg DM) CH, (Kcal/con/ngay) CH^ (Kcal/kg DM) KLbo dau TN (kg) KLbo CUOI TN (kg) TKL/ngay (g)
CP14 16.003 2.287' 2.126' 309^
367 381 1-000
Nghiem thiic CP17 15.387 2.301'' 2.159'' 327*
368 380 905
CP20 14.955 Z329' 2-215^
345 355 366 786
0,141 0,001 0,006 0,000 0,480 0,505 0,827
213,5 0,765 3,476 0,319 6,658 8,369 234,9 k. K^T L U A N
Tang miic NDF eua TAHH trong khau pban ehua anh hudng de'n kha nang tieu thu va heu hda dudng cha't tbuc an tren bd eai Brahman, Muc NDF 16% eiia TAHH cho ke't qui tdi uu tren bd cai ta gid'ng Brahman.
TAIUIUTHAMKHAO
1. Abate A.L. a n d M a y e r M (1997). Prediction of the useful energy in tropical feeds from p r o x i m a t e composition and in vivo derived energetic contents: 1. Metabolisable energy. Small R u m i n a n t Research, 25; 51-59.
2 AOAC (1990), Official m e i h o d s of analysis (15th edition), Washington, DC, 1: 69-90
3, Arclovich H.M., A b n e y C S , , Vizcarra J.A. a n d G a l y e a n M.L. (2008) Effects of Dietary N e u t r a l Detergent Fiber on Intakes of Dry Matter a n d N e t Energy by Dairy a n d Beef Cattle Analysis of Published Data. T h e Professional Anim Sd,, 24:375-83.
•1 B r u i n e n b e r g M . H . (2002), Factors affecting digestibility of temperate forages from s e m i n a t u r a l grasslands. Grass and forage science, 57, 292-01.
5, Dinh Van Cai va H o a n g T h j N g a n (2017), Ket q u a n g h i e n cihl ve thlic 3n va d i n h d i r o n g cho trau. b o (ai t r u n g tam nghieti cihl va p h a t trien gia sue lon, Hoi nghi C h a n nuoi Thii J' toan quoc 3/2017, t r a n g 56-66.
6, Vu Ctii Cirong, N g u y e n Dwe C h u y e n , D i n h V a n T u y e n , Pham Bao Duy, Bui T h j T h u H i e n , N g u y i n Viet D o n , N g u y e n Van Q u a n va Le T h i O a n h (2010). A n h h u o n g cuo giong, ioai gia siic don ty 1? tieu h o a va gia trj d i n h dirong ciia mot so lo^i thiic Sn tho d u n g cho gia siic nhai lgi. T^p chi Khoa hpc C g n g n g h ? C h a n nuoi, 24: 37-45 7, D i n h Van D u n g , S h a n g W. a n d Yao W. (2014). Effect of
C r u d e Protein L e \ e l s in Concentrale a n d Concentrate Levels in Diet on In vitro Fermentation, Asian J A n i m Sa, 27(6)' 7 9 7 ^ 5 ,
S H o a n g Kim Giao (2018). Phat trien chan nuoi bo Oiit o Vi?t Nam k h o k h a n t h u ^ n lpi va n h i r n g bai hpc d u g c n i t ra.
Tap chi Khoa hoc Kv thu^t C h a n nuoi, 234, 6-15.
^ Harper K.J. a n d McNeill D . M (2015) T h e Role N D F in the Regulation of Feed Intake a n d t h e I m p o r t a n c e of Its Assessment in Subtropical R u m i n a n t Systems (the Role of NDF in t h e Regulation of Forage Intake) - Revieiv.
A g n e u l t u r e . 5: 778-90.
10 M c D o n a l d P., E d w a r d s R.A., G r e e n h a g h J.F.D. a n d M o r g a n C A . (2010). Animal Nutrition (7th ediHon), L o n g m a n S d e n t i h c a n d Technical, NY USA, 11. M i n i t a b Reference M a n u a l (2010). Release 16 for
W i n d o w s , Minitab Inc. USA.
12. D a n h M o (2018). Effects of t h e concentranle level on performance a n d m e t h a n e emission from (red Sindhi x VietNamese) crossbred cattle in the m e k o n g delta, T^ip chi Khoa hoc Ky thu^l C h a n nuoi, 235: 54-59, 13- M i l l s J.A.N., E. K e b r e a b , C M . Yates, L.A. C r o m p l o n ,
S.B. C a m m e U , M.S. D h a n o a , R.E, A g n e w a n d J. France (2003). Alternative a p p r o a c h e s l o predicting meliiane emissions from dairj' cows. J. A m m , Sci,, 81, 3141-50, 14 Le D u e N g o a n , D i n h V a n D i i n g , S e a r c h i n g e r T.D. va
Le D i n h P h u n g (2017) Hien tr?ng v a kich ban giam phat thai khi m e t a n tii d u o n g tieu hoa ciia he thong nuoi b o thit q u a n g canh q u y m o n o n g h o 6 Q u a n g Ngai, T g p chi Khoa hgc T r u o n g Dai hoc Can Tho. 46b: 1-7, 15, P e n g H . Q . , K h a n A.N., Xue B., Yan H.T. a n d W a n g S.Z
(2018). Effect of different levels of protein concentrates s u p p l e m e n t a t i o n on t h e g r o w t h performance, plasma a m i n o acids proOe a n d mTOR cascade genes expression in early-weaned v a k c a l v e s . A s i a n - A u s t r a l a s ] , A n i m . S c i , 31(2)'218-24.
16, D o Van Q u a n g , N g u y e n X u a n Ba, Doyle TP., D a u Van Hai, Lane A.P., M a l a u - A d u l i E,A., N g u y e n H u u Van a n d P a r s o n s D, (2015) Effect of concentrate s u p p l e m e n t a t i o n o n n u t r i e n t digestibility a n d g r o w t h of Brahman crossbred cattle fed a basal diet of grass a n d rice straw, J.
A m m . S d . Tech., 57' 35
17 N g u y e n V a n T h w o n g (2016). L^i tao b o lai h u o n g thjt trong san xual. T a p chi Khoa hpc Cgng N g h ? C h a n nuoi, 69, 8-10-
18. Van Soest P.J., R o b e r t s o n J.B. a n d Lewis B.A. (1991).
M e t h o d s for dietarv fiber, neutral detergent fiber a n d non-starch polvsacharides in relation to animal nutrition, J. Dairy Sd-, 74', 3583-98.
19- Xia C , R a h m a n A.U.M., Yang H., S h a o T., Q i u Q., S u H. a n d C a o B. (2018), Effect of mcreased dietary c r u d e protein levels o n production performance, nitrogen utilisation, blood metabolites and r u m i n a l fermentation of Holstein bulls, Asian ] A n i m . S d , 31(10)' 1643-53 20 Y u a n g k l a n g C . , V a s u p e n K . , B u r e e n o k S., W o n g s u t h a v a s
S. a n d K h o t s a k d e e J. (2010) C u r r e n t Status of Protem R e q u i r e m e n t for Thai B r a h m a n Cattle m the Northeast of Thailand, Khon Kaen Agr, J,. 38(Sup)-152-57
I'fJlTTr'ltA,, •,vo- £^ 2^5 - th^r^ 6 ;?.^.m 2019
