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NH HNG CA S B SUNG B U NNH TRONG KHU PHN LN TNG TRNG, T L TIU HA

DNG CHT V HIU QU KINH T CA TH LAI

Nguyn Th Kim ng1

ABSTRACT

A complete randomized experiment was carried out to assess growth performance,

nutrient digestibility and economic returns determined by crossbred rabbits fed para

grass (PG) basal diets supplemented different levels of soya waste (SW) included in five

diets with three replicates and 4 rabbits per experimental unit. The results indicate that

the rabbits fed para grass supplemented SW had significantly (P

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nh l cng nh chn nui cng nghip. Tht th c gi tr dinh dng cao nhiu m, t m, hm lng cholesterol thp ph hp vi nhiu la tui. V vy tht th c th tr thnh loi thc n ph bin trong ba n hng ngy ca con ngi.

nc ta c bit l vng ng Bng Sng Cu Long c ngun rau, c mc t nhin phong ph nh c lng ty, c u, a cc, bm bm, rau mung, rau lang, lm thc n cho th. Cc ph phm cng nghip nh b bia, b u nnh, b u xanh, Trong b u nnh sn c cc ni ch bin tu h, chao, sa u nnh, c hm lng m kh cao (20,7%) c th s dng thay cho ngun m t thc n cng nghip c gi thnh cao b sung trong khu phn nui th. Tuy nhin nhng nghin cu v vic s dng loi ph phm ny trong khu phn nui th cn hn ch.

V vy mc tiu ca ti nhm xc nh mc ti u ca b u nnh trong khu phn nui th, t l tiu ha dng cht ca cc khu phn th nghim v hiu qu kinh t ca vic s dng b u nnh trong khu phn nui th, t khuyn co kt qu t c n ngi chn nui.

2 PHNG TIN V PHNG PHP TH GHIM

2.1 Th th nghim

Th c s dng trong th nghim l ging th lai (c sn xut t th a phng v th lai ci tin) 50 n 55 ngy tui, c trng lng trung bnh khong 450- 500g. Th nghim tiu ha dng cht c tin hnh lc th khong 100 ngy tui, c trng lng khong 1,4- 1,5kg. Th c tim phng bnh cu trng, bi huyt v k sinh trng trc khi a vo th nghim.

2.2 B tr th nghim

Th nghim gm hai giai on, th nghim nui dng v tiu ha dng cht c b tr theo th thc hon ton ngu nhin vi 5 nghim thc tng ng vi 5 khu phn v 3 ln lp li. Mi n v th nghim gm: 2 th c v 2 th ci c b tr vo mi ngn chung, c trng lng tng ng nhau khong 500g/con.

Bng 1: Cng thc khu phn th nghim

Thc liu Nghim thc

BDN0 BDN100 BDN200 BDN300 BDN400

B u nnh 0 100 200 300 400

C lng ty T do T do T do T do T do

THH 10-20g 10-20g 10-20g 10-20g 10-20g

BDN0, BDN100, BDN200, BDN300, BDN400: b sung BDN cc mc 0, 100, 200, 300 v 400 gram theo th t. THH: Thc n hn hp.

2.3 Chung tri v cch qun l

Su mi th th nghim c b tr ngu nhin vo 15 ngn chung lng c lm bng li ch v g (0,5x 0,5x 0,6m). Th c trng lng trung bnh tng ng nhau trong mi ngn chung lng. Mi ngn chung c t mng n, mng ung. S dng li nylong v plastic c t di mi ngn chung hng

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phn v nc tiu ca th. Chung, mng n, mng ung c lm v sinh mi bui sng.

2.4 Thc n th nghim v cch nui dng

B u nnh c mua mi ngy c s sn xut sa u nnh ti Thnh ph Cn Th. Thc n hn hp mua ca hng thc n gia sc. C lng ty ct hng ngy xung quanh khu vc Trng i Hc. Th th nghim c cho n 3 ln/ ngy vo lc (lc 8,11 v 17gi). B u nnh v c lng ty c cho n vo bui sng v chiu. Cc loi thc n c cn trc khi cho n, thc n tha c thu v cn vo sng hm sau. Mi hai tun thc n v thc n tha c thu v x l phn tch thnh phn ha hc. Th c cn trng lng hng tun vo bui sng, trc khi cho n tnh tng trng.

Th nghim tiu ha dng cht c thc hin trong 6 ngy. Cc mu thc n, thc n tha ca tng n v th nghim c cn tnh mc n vo/ngy. Phn v nc tiu c thu 3 ln/ ngy (lc 7, 13 v 18 gi). Mu phn v nc tiu c thu v cn trng lng theo tng n v th nghim. Cc mu thc n, thc n tha v phn c sy kh 55oC, nghin mn. Sau trn u cc loi mu ca 6 ngy theo tng n v th nghim, mt s mu c chn phn tch cc thnh phn ho hc nh DM, OM, CP, NDF, Ash. Ring nc tiu sau khi thu s c cn v phn tch nit ngay trong ngy.

2.4 Cc ch tiu o t

Lng thc n v dng cht n vo, tng trng, h s chuyn ha thc n, hiu qu kinh t ca khu phn giai on th nghim nui dng.

Lng thc n v dng cht n vo, t l tiu ha cc dng cht: DM, OM, CP v NDF v lng nit tch ly (g/kgW0,75) giai on th nghim tiu ha dng cht.

TLTHDC (%) = (Lng DCnvo Lng DCphn)/ Lng DCnvo x 100 (Mc Donald et al., 2002).

2.5 Phn tch thnh phn ha hc

Cc loi thc n cho n nh c lng ty, b u nnh, thc n hn hp, thc n tha v phn th c phn tch cc ch tiu nh vt cht kh (DM), Nitrogen (N), m th (CP) (N x 6.25) v tro theo phng php ca AOAC (1990). Phn tch hm lng x trung tnh (NDF) theo qui trnh ca Van Soest et al. (1991).

2.6 X l thng k

S liu c phn tch phng sai bng cch s dng ANOVA theo m hnh tuyn tnh tng qut (GLM) ca chng trnh Minitab, version 13 nm 2000. Khi th nghim F c ngha thng k mc P

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3 KT QU V THO LUN

3.1 Thnh phn ha hc ca thc liu thc n dng trong th nghim nui dng

Bng 2: Thnh phn ha hc ca thc liu thc n dng trong th nghim nui dng (%DM)

Thc Liu DM OM CP NDF Ash

B u nnh 10,4 93,9 20,7 44,5 6,12 C lng ty 20,9 82,9 10,6 77,8 17,1 Thc n hn hp 87,0 91,1 20,0 23,6 8,90

DM: vt cht kh, OM: vt cht hu c, CP: protein th, NDF: x trung tnh, Ash: tro

Bng 2 trnh by thnh phn ha hc ca c lng ty, b u nnh v thc n hn hp trong giai on th nghim nui dng. C lng ty c hm lng DM l 20,9% cao hn b u nnh l 10,4%. DM ca c lng ty s dng trong th nghim ny cao hn kt qu nghin cu ca Trng Th Anh Th (2008) l 18,9%, Nguyn Th Xun Linh (2005) l 16,4%. B u nnh c DM (10,4%) tng ng vi kt qu nghin cu ca Trng Th Anh Th (2008) l 10,5% v thp hn kt qu nghin cu ca ng Hng Cng (2008) l 11,1%. B u nnh c hm lng CP l 20,7% l ngun m thch hp cho nhu cu tng trng ca th. Hm lng CP ca b u nnh trong th nghim cao hn kt qu nghin cu ca Trng Th Anh Th (2008) l 19,4% v thp hn kt qu nghin cu ca ng Hng Cng (2008) l 21,7%. C lng ty ca th nghim c hm lng NDF l 77,8% cao hn nhiu so vi b u nnh 44,5%. Qua cho thy, c lng ty c hm lng x cao, m thp, trong khi b u nnh c hm lng m cao, v vy mt s phi hp mt cch hp l ca hai loi thc n ny gip th tn dng tt ngun thc n v mang li hiu qu cao.

3.2 Lng b u nnh v c lng ty tiu th ca th nghim nui dng

Bng 3: Lng b u nnh v c lng ty tiu th ca th th nghim nui dng (g/con/ngy)

Ch Tiu Khu phn (BDN)

SE / P BDN0 BDN100 BDN200 BDN300 BDN400

CLT ti 290a 243ab 174bc 130c 106c 15,5 / 0,001

BDN ti 0,00a 105b 226c 307d 346d 10,5 / 0,001

DMCLT 60,7a 51,0ab 36,0bc 27,0c 22,0c 3,20 / 0,001

DMBDN 0,00a 10,9b 23,6c 32,0d 35,9ds 1,09 / 0,001

Cc gi tr mang cc ch a, b, c, d trn cng mt hng th khc bit c ngha thng k mc P

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3.3 Lng thc n v dng cht n vo ca th trong th nghim nui dng

Bng 4: Lng thc n v dng cht n vo ca th trong th nghim nui dng (g/ con/ngy)

Ch tiu Nghim thc

SE / P BDN0 BDN100 BDN200 BDN300 BDN400

DM 74,8 75,9 75,0 72,9 72,0 3,01 / 0,890

OM 63,1 65,2 66,0 65,1 64,8 2,52 / 0,940

CP 9,23a 10,5ab 11,8bc 12,3c 12,6c 0,37 / 0,001

NDF 50,5a 47,7ab 42,3abc 38,6bc 36,5c 2,35 / 0,008

Cc gi tr mang cc ch ci a, b, c trn cng mt hng th khc bit c ngha thng k mc P0,05), bin ng t 72,0-75,9 g/con/ngy. Kt qu ny thp hn so vi kt qu nghin cu ca Phm Hunh Khit Tm (2007) l 72,5-89,2 g/con/ngy v cao hn kt qu nghin cu ca Trng Th Anh Th (2008) l 65,7-71,2 g/con/ngy.

Hm lng CP n vo tng dn c ngha thng k (P

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Bng 5 ch ra rng trng lng th lc kt thc th nghim tng dn khi tng b u nnh qua cc nghim thc, cao nht nghim thc BDN300 l 1779g (P

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Bng 6 trnh by thnh phn ho hc ca thc n s dng trong giai on th nghim tiu ha. Chng ti nhn thy lng DM% v CP% ca c lng ty v b u nnh gn tng ng vi kt qu giai on nui dng.

3.6 Lng thc n v dng cht tiu th ca th trong th nghim tiu ha

Bng 7: Lng thc n v dng cht tiu th ca th trong th nghim tiu ha

Ch tiu

Khu phn

SE / P BDN0 BDN100 BDN200 BDN300

BDN40

0

Lng n vo (g/con/ngy)

DM 85,2a 85,2a 69,8b 66,1b 64,9b 1,09 / 0,001

OM 73,2a 74,4a 62,5b 59,8b 59,1b 0,96 / 0,001

CP 10,5a 11,6b 11,6b 11,8b 12,0b 0,11 / 0,001

NDF 50,3a 47,6a 34,4b 30,7c 29,3c 0,78/ 0,001

DM: vt cht kh, OM: vt cht hu c, CP: protein th, NDF: x trung tnh

Cc gi tr mang cc ch ci a, b, c trn cng mt hng th khc bit c ngha thng k mc P

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ca chng ti ph hp vi nghin cu ca Doan Thi Gang et al. (2006) CPD t 73,3- 84,7%; v Trng Th Anh Th (2008) CPD t 71,8- 86,0%.

T l tiu ha NDF cc nghim thc c b sung BDN cao hn c ngha thng k (P

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Phm Hunh Khit Tm. 2007. nh hng cc mc rau lang da theo trng lng c th ln kh nng sn xut tht v s tiu ho ca th lai. Lun vn tt nghip i hc, Khoa Nng Nghip v Sinh Hc ng Dng, Trng i Hc Cn Th.

Trng Th Anh Th. 2008. nh hng ca l rau mung thay th c lng ty trn s tng trng t l tiu ho dng cht v tch lu Nit ca th. Lun vn tt nghip i hc, Khoa Nng Nghip v Sinh Hc ng Dng, Trng i Hc Cn Th.

Van Soest, P. J., J. B. Robertson and B. A. Lewis. 1991. Symposium: Carbohydrate

methodology, metabolism and nutritional implications in dairy cattle: methods for dietary

fiber, and nonstarch polysaccharides in relation to animal nutrition. J. Dairy Sci. 74:

3585-3597.