- Th^nh phan hoa hgc va tmh khong thuan nhat: Chi kich thuoc vd tinh la chua du dl xac dinh
ị4.ịyirut sm
1.43.8. Sy nhfin len ciia virutRota trong te bao
Cdc đc trung chung ciia qua trinh nhan Idn cua vimt Rota trong nudi cay td bdo than khi nhu sau:
- Vifc nudi cay hdu het cdc chimg vmit đi hdi cd sy bd sung cdc enzym phdn giai protein vdo mdi tmdng nudi ciy nhdm tach protein capsit ldp ngoai VP4.
- Qud trinh sao chep xdy ra hodn todn trong tl bdo chit.
- Te bdo khdng chiia cdc enzym dimg cho sao chep sgi kep ARN, vi the virut phdi ty cung cip cac enzym can thiet.
- ARN sgi (-) dugc dimg Idm khudn de sao chep sgi (+) nhd enzym ARN polymeraza phu thudc ARN. Sgi (+) nay dimg dl tdng hgp cdc protem, đng thdi phien ma tao ARN sgi (-). Khi sgi (-) dugc tdng hgp hodn todn, nd duy tri vifc lien ket vdi sgi (+).
- Cdc dỏn ARN sgi kep dugc hinh thdnh trong cac hat vimt mdi vd cdc ARN sgi kep hay cac ARN don sgi dm khdng bao gid tin tai ty do trong cdc tl bao nhiem.
- Cdc hat vimt chua hoan chinh hinh thdnh trong qud trinh lidn kit vdi
nguySn sinh chdt cua vimt se dugc hodn chinh nhd sy ndy chdi qua mang ludi ndi chit ciia tl bdọ Trong qud trinh ndy, cdc hat vimt cin cdc protein capsit ldp ngodi ciia chung.
- Sy phan gidi td bdo se gidi phdng cdc hat vimt khdi cac tl bao nhiem. Cdc giai doan chi tilt ciia qud trinh sao chdp vimt Rota dugc md td dudi đy:
Giai dôn hipph^, xdm nh^p vd cM vd:
Cdc dilm tiep n h ^ đc hifu (receptor) tren bl mdt te bao chua hodn toan dugc bilt rd. Nhung cdc nghien cuu vl sy gdn cua chiing SAll len cdc td bdo MA104 cho thiy cd khodng 13 nghin dan vi tiep nhgn tren mgt te bdọ Sy gan khdi dau phy thugc vdo natri vd axit sialic tren mdng tl bdọ Sau khi gdn vdo tl bdo khodng 60 din 90 phiit, vimt xdm nhap vdo tl bao nhd enzym phan gidi protein. Enzym lysosome cua te bdo cd tdc dyng pha vo capsit ldp ngodi cua vimt.
Sy xdm nhdp ciia vimt Rota ngudi phy thudc vao vifc tach ldp vd ngodi ciia vimt bdng trypsin. Vimt da dugc xir ly trudc bang trypsin se true tiep xdm nhdp qua mdng te bao vdo trong bdo tucmg cua td bdọ
Mgt gid thuylt khde cho rdng, nhiing hat vimt da dugc hoat hod bdng trypsin dinh vdo mang tl bdo sd bam tryc tilp axit nucleic qua khe hd hinh thanh giira capsomer va Id tren mang te bdọ Co chl ndy tucmg ty nhu phdng axit nucleic vdo te bdo vi khuan ciia phage .
Nhihig h^t vimt chua dugc xu ly bdng trypsin se vdo td bao bdng con dudng thyc bao, nhiing virion ndy sau khi gdn vdo mdng tl bdo khodng 20 phiit se vdo trong lysosome .
Khi ARN ciia vimt da vdo trong bao tuong tl bdo cdm thu thi qua trinh sao chep se dugc tien hdnh. Qud trinh dich md khdng đng đu, cdc bdn sao Id nhiing sgi ARN duong sao chep tir sgi ARN dm. Sgi ARN duong vd sgi ARN dm xudt hien d 3 gid dau sau nhiem trimg. Sau 3 gid, mire dg phien ma tdng din len va keo dai tir 9 den 12 gid. Tai thdi diem nay, lugng ARN soi ducmg Id tdi dạ Ty le tong hgp ARN sgi duong vd sgi am thay đi trong suot qua trinh nhiem trimg vd mire dg tong hgp tdi da sgi am xuit hien vdi gid tmdc khi lugng ARN sgi ducmg dugc tdng hgp tdi dạ
Cdc protein ciia vimt dugc tdng hgp đng thdi vdi sy sao chep ARN ciia vimt. Cdc protein cau tnic bao gom VPl, VP2, VP3, VP4, VP6 vd VP7 cd tdc dung tao capsit ciia vimt. Cdc protein khdng cau true bao gdm NSPl, NSP2, NSP3, NSP4, NSP5 tham gia vdo qud hinh sinh tdng hgp ARN.
Giai dogn lap rdp vd gidi phdng
ARN sgi kep tao thdnh se dugc ldp rap vai cdc protem cau tnic tao thanh hat vimt hodn
chinh trong bdo tuong te bao vd dugc gidi phdng ra ngodi te bdo bdng cdch ly gidi tl bdo chii hoac ndy choị • ft" •*V-*" " " » • R i i e j i J'.dl L;ipr,ip iMpMl «Ji - * - % U LVịJi- t Giaipliiin^
1.5. Thd
1.5.1. Dac tinh sinh hpc ciia tho
Thd Id dgng vat cd vii nhd dugc xep vdo hg Leporidae thudc bd Lagomorpha, sinh sdng d nhieu noi trdn the gidi Thd dugc phdn loai thanh 7 loai, didn hinh nhu thd rimg Chau Au (Oryctolagus cuniculus), thd dudi bdng (gidng Sylvilagus; 13 species), thd Amami (Pentalagus fumessi, 1 lodi thd quy hiem d Amami Oshima, Nhdt). Cdn nhilu loai thd khde trdn the gidi, thd dudi bdng, thd cgc vd thd rimg dugc xIp vdo bd Lagomorphạ Tudi tho ciia thd tir 4 tdi 10 ndm, thdi ky mang thai khodng 31 ngdỵ
1.5.2. Cdc lop tho dirffc nudi vd *«• dung tgi nir&c ta
Hinh 1.10. Hinh dnh tho tai Vift Nam
Nghe nudi thd da cd ty lau đi d nude ta, tir Bac chi Nam. Tir ndng thdn vd tham chi nudi ngay khu dan cu thdnh thị Bdi vi thd rat de nudi, cho thu nhdp nhanh va Igi nhudn cung rat caọ
Tmdc tinh hinh dich ciim gia cim dang lan rdng, viec nudi thd 1dm thyc phdm, da dugc nhieu dja phuong xem nhu mdt trong nhiing gidi phdp thay thẹ
1.5.2.1. Ddc tinh chung
Nudi thd tucmg doi don gidn, ngudn thiic an de kilm, da so tan dyng rau xanh, luong thyc trong nhd. Chi phi cho chuong trai, thudc phong bfnh, cdng cham sdc ciing khdng caọ
Thd Id gia siic cd nhilu uu thi: De khde, phat trien nhanh, sdn phdm lai cd gid tri tieu dimg vd xuat khaụ
Thd thugc bd gdm nhim (Rodentia), tren the gidi cd rat nhieu gidng nhu: Thd trdng khdng Id Bauxcat vd Flandra (Phdp) trgng lugng 6,5 - 6,8 kg, Thd trdng BeUe (Phdp), Thd trdng Nga (Idn va nhd), Thd Tan Tay Lan trdng, Thd Cahfomia (My), Thd Chmchila (Anh)... Rieng tai Viet Nam, hifn nay khdng con gidng thd thuin, phin Idn bi lai tap, chi cd 3 gidng chinh la: Thd trdng Tdn Tdy Lan - Vift Nam (nhdp tir Hungari 1978), tiid xdm Vift Nam, tiid den Vift Nam.
Thd nudi hifn nay, phin Idn cd nguon gdc lai tao tir thd hoang chau Au va chau Phi vdo thdi Trung cd. Thd hoang co siic de khang tdt hon thd nhd. Thd nha cd khoang 80 loai, can cii theo trgng lugng hoac theo mdu sic long de chia nhdm gidng thd.
Trgng lugng tir 0,9-2,7 kg (thd nhd con), tir 2,8-4 kg (tiid tinng bmh), hi 4,1-5 kg (thd to con), tren 5 kg (thd khdng Id).
Thd trung binh vd hai to con, thudng an it, Idn nhanh. Thit ngon, xuong nhd. Nudi liy thit cd Igị
Thd khong lo dn nhieu, xuong to, it thit, sinh sdn ch|im, hieu qud kinh tl thip. 1.5.2 J . Chgn gilng tho
Tmdc bet phdi chgn Igc con gidng tir cac ca sd gidng tdt vd dn dinh. Thd gidng phai cd tinh dye hdng hdi, nharih nhen. Dugc nudi tit 6 tuin den 5 thdng. Long bdng vd nliilu, bd Idng min vd sdng. To con, đi đn, ngyc sau vd nd. Lung rgng, mdng, diii nd nang, khdng đng huylt. Vdnh tai bdng vd sach. Bdn chan vd ke chan khdng ghẹ Mi mat khdng sung vd trdng mdt trong. Bung mim cd long xdp. Dudi khdng dinh phdn udt. Da lung mIm vd khdng trdc Idng. Cue phdn to trdn vd khd. Thd chdc thit, bilu dfng. Dugc tiem ngira đy diị Ty le thy thai tren 70%, de dugc 5-6 liia/ndm, moi Ilia 6-7 con. Sd con so smh sdng sau 15 gid phdi dat 6 con trd len. Ty If nudi sdng tir so sinh din cai siia (30 - 35 ngay) tren 80% (mSi liia cai sGa tren 5-6 con), thich nghi tdt, khoe manh, khdng bfnh tdt, tdng trgng nhanh (binh qudn 30gr/con/ngay)... Loai bd gidng khi cdc chi tidu sinh sdn kdm, mdc bfnh tat lau ngdy khdng khdi, the lyc gay yeụ Khdng nen chgn mua thd dang cd thai ho§c đ sinh sdn vl nudị Thd dang mang thai, di chuyen cd the chdt hoac de non. Thd di khdp kliieng, lung udn cong, cao chan, lilm long, nghien rdng, hoi thd nhanh... la dau hifu thd bfnh. Khi thd hi bfnh dudng mdt, viem vii, viem than, viem tinh hoan, bfnh dudng hd hap, thudc dieu tri tdn kdm gip nhilu lin gid tri mgt con thd. _
3 giong thd ngôi mdi
Tho New Zealand trdng: Cd ngudn gdc tir New Zealand, nudi phd bien chau Au, Mỵ New
Zealand trdng Id gidng thd tim trung, mdn de (mdi nam de 6-7 liia, moi lua 6-8 con), smh tmdng nhanh, thdnh thyc sdm, nhilu thit, phii hgp vdi phuong thiic chdn nudi cdng nghiep va gia dmh.
Thd cd ngoai hinh Idng đy, mdu trdng tuyen, mdt hong, trgng lugng tmdng thanh tir 5-5,5kg/con Giong thd New Zealand trdng nhdp vdo Viet Nam td ra thich nghi vdi nhidu vimg sinh thdi khde nhaụ
Tho Panon: Giong thd ndy xuat phdt tir đng cua giong New Zealand trdng duoc chgn loc
nghiem ngdt ve khd ndng tdng trong vd trgng lugng tmdng thdnh tao nen. Thd Panon ciing gidng nhu thd New Zealand nhung tang trgng cao hon. Trong luong khi trudng thanh dat 5,5-6,2kg'con, Giong thd ndy cung da dugc nudi dat ket qud d nhieu vimg nude tạ
Tho California: cd ngudn gdc tu My, dugc lai tao giira 3 gidng thd: Chinchila, thd Nga, thd
New Zealand. La giong thd tam trung, trgng lugng tnmg binh 4,5-5kg, cd than ngdn hon thd New Zealand, Idng trdng nhung tai, mui, bdn chdn vd dudi cd dilm Idng mdu den. Giong thd nay da duoc nudi nhieu d Viet Nam.
1.5.2.4. Chuong nudi
Chudng nudi phdi bdo đm thdng thoang, sach se, mat me ve miia he, am ap ve miia đng, Trdnh mua tat, gid liiạ Thilt kl chudng nudi phdi dat d nhiing noi thudn tien cho viec quet dgn ve sinh, de đng chdm sdc, each xa chudng heo, chuong gạ Khdng nen dat chudng thd d nm da nudi heo, ga .. vi dl nggt ngat vd hdi thoị Cd rao chdn tranh chudt vd meo gdy haị
Chuong bdng ludi sat cd gian do bdng sdt hodc bdng cay phu ldp son, cao cdch mat dit tren 0,6m. Thd to tir 6 tuin den 4 thdng tudi cd the nudi 10 con trong chuong kich co 2x0,7x0,5m; loai chuong cd kich co 0,7x0,5x0,5m chi danh nudi 1 con thd tmdng thanh tren 4 thang tudị
Quy cdch chuong phii hgp nhdt Id khdi hop chii nhat, dai 90cm, rgng 60cm, cao 50cm, cd thi chia 1dm 2 ngdn, moi ngdn cd khay ludi dyng thiic dn thd xanh, mdng dyng thirc an tinh, mdng dyng nude cho thd, kich thudc vira phdi, bdo đm ve sinh va khdng hu haọ Moi ngdn nudi 5- 6 con thd thit, 2 con hau bi hodc 1 con sinh sdn. Chudng cd the lam 1 tang hodc 2 ting, 1 ting thi ndp md mdt tren, 2 ting thi ciia md phia tmdc, dudi day tang tren phai cd khay hung phan
Xay dyng thilt bi cho thd uong nude: Dung cu nay rdt dcm gian va de lam, cd the ty thiet ke nhu sau:
Dung cu cho tho u6ng nude cd thi lam bing sanh, sil hoac đ xi mang binh chiu cao 8- lOcm, inieng rOng 10- 15cm dl thd khong dim chin vao vi khong lit d6 dugc. Dl giu ve sinh dupe nuoc uong, co the lim van nuoc bing fing kim loai hoac duiy tinh day cim vio mit chai, mit can doc ngugc, co gii gia vao thinh 16ng dl tho hiit him dupe nuoc. Hoac lim khay nuoc co chai chiia nude đc ngupc.
0 de: BCich thudc vira phii, dai 50cm, rdng 35cm, cao 20cm, mat tren cd nip day, mpt nira cd djnh, mpt nira lim cua cho thd ra viọ 1- 2 ngiy tnrde khi de, thd me vio d nhd Idng bvmg hdn voi đ lot de chuan bi dẹ Cho nen, phii dat d de vao chudng khi thd mang diai dupe 27-28 ngay vi liy ra khi thd eon tren 20 ngiy
1.5.2.5. Thic i n
Thd in dupe rat nhieu loai li cay vi qui cụ Tuy nhiJn, cic loai cii qui nen cit thinh milng nhd, khoai tay nen ludc chin (dl phdng chit dpc khi cil khoai tiy mpc mim). Thiic in nude udng phii thit sach, khdng dinh dit eat bin, khdng nhiem dich benh, chit dpc (thudc frit siụ..). Vi thd rit min cim vciri cic b$nh d dudng tidu hda nhu chudng bung diy hoi, benh ciu trimg, benh sin Ii gan, b?nh tiSu chiy do Ẹcolị..
Can cho thd in cic loai li cay, thin cinh d xa mit dit (cinh li keo diu, li diu, la rim but...), cic lo5U cd, rau tr6ng tren can, dit mau (cd voi, ngpn li mia, rau Ii diu, sin diỵ..). Khdng ndn cho thd in rau cd mpc tu nhidn ncri im udt, hd aọ Nlu dimg beo sen thi phai niu chin cho in die nhu cho Ipn in.
Thd con nudi vii tuin den 4 thing tuoi, chi cin cho in cim vien li diị An them rau cd, thd de bj b^nh tieu chiy vi chet. Thd trudng thanh, siic dl khing tdt hon, cd the cho in rau cd rua that s?ich de rio nudẹ Lupng rau cd mSi ngiy chimg 20g/ecn.
Thure in vien phii dim bao tiiinh phan dinh duong cho thd ting trudng theo thdi gian nudị Thd con nudi din trudng thinh cd nhu cau dinh duong mdi ngiy tir 8-10% protein, 2-4% lipid, 10-
20% glucid, tren 4 thing taoi them mdt it chit xạ
Thd cd thai vi cho con bii cin lupng dinh duong mdi ngiy tir 10-15% protein, 5-7% lipid, 10-
20% glucid, mdt it chit xa cin thilt.
Thd lira in chimg 30-50g cam vidn, moi ngiy chia hai lan. Thd due gidng, thd cai nudi con va mang thai, in chimg 80-1 DOg cim vien. Chia hai lin sang vi chieụ
Thiic in cim vien nudi thd dupe che bien tir ngudn ngii cdc cd sin. Nhu cau lupng thiic an chimg 4% trpng lupng co the thd.
M5i con thd can tir 0,2-1 lit nude trong ngiỵ Cho thd udng nude sach, khdng cd ham lupng sit Nude u6ng phii dupe ling Ipc khir triing. Nude lanh dudi 8°C khdng cho thd udng. Nhiet dp thich hpp cho thd udng li 15°C.
Nhilu ngudi cho ring thd khdng cin udng nude li sal lim vi nude rit cin cho trao đi chit. Thd chet khdng phii do udng nude vi hay an cd udt mi vi udng phii nude ban, in rau bj nhiem đc...
1^^.6. Chdm sdc
Thd rdt nhay cam vdi nhiing tdc đng cua mdi tmdng. Phan iing xdu vdi nhihig thay đi dot ngdt ve dn udng, chdm sdc, khi haụ..Khi nudi, can luu y den cdc nguyen tdc chdm sdc nhu sau:
Thd rdt dl bi bfnh rdi loan tidu hda, bfnh dudng mdt. Do đ nen tao ra mgt phdn xa cd dieu kifn d thd ve thdi gian dn vd thii ty thiic an. Ddc tinh lodi thd, rdt thich an dem, ban ngdy ngu nhieụ. Ban đm, thd dn gap 2- 2,5 lin ban ngdỵ Neu cho an sai nguyen tdc ndy, thd se chdm Idn.
Mgt so thdng tin lien quan, qua kinh nghiem thyc te cho thdy:
Budi sdng (tir 7 gid den 12 gid): Vifc đu tien la cho thd udng nude, tiep theo la an thiic dn hat (ngd, thdc.) hodc hon hgp thirc an tinh (cam, ngd, bdt khodng...). Den 9-10 gid cho an thuc dn thd xanh tuoi (1/3 sd lugng khdu phin).
Budi chieu (tir 14 gid den 17 gid): Ddu gid cho an cii, qud đ thdi Idt (khoai lang, bi ngd, du du, cd rdt, su hdọ..) hodc cdc loai thiic dn mdm (cdm ndu trdn lin, ba chd, rau thdi nhd...).
Buoi tdi (ban dem): Cho an cdc logi thirc dn xanh nhu cd, la cay, rau xanh... (2/3 khdi lugng khau phin de thd dn ca đm).
Ban dem tuyf t đi khdng cho thd dn thiic dn hat, thiic dn hon hgp tinh. Nlu ban ngay thd dn khdng bit thi phdi vet sach mdng. Nlu dl thira chugt se Idn dn vd cdn chet thd, nhat Id thd con mdi đ.
Trong thdi gian nudi v6 beo, nen gidm bdt dnh sang, tao khdng gian yen tinh dl thd nghi ngoi, ngu sau khi dn. Trudc khi 1dm thit 7 ngdy, ndn gidm thdc dn thd (cd khd, ram...) thi chit lugng thit sS tit vd ngon hon.
CHL^CfNG n .
NGUYEN VAT LIEU VA PHU*OfNG PHAP NGHIEN ClTU 2.1. Nguyen vat lifu va phircmg phap san xuat khang nguyen
2.1.1. Nguyen vat lieu vd phuong phdp sdn xuat khdng nguyen Sdi Nguyen vat li^u
Vimt Sdi tir chiing Edmonston do vifn Kitasato cung cdp; Te bao Vero do vien Kitasato-Nhat ban cung cip;
Mdi tmdng hda chit: MEM, NaHCOs 7,5%., huylt thanh be (BS), PBS (-), khdng sinh P-S, Hank, va nhimg nguyen vat lieu can thiet khac dii de sdn xuit khang nguyen Sdi
Sdn xuat khdng nguyin Soi
Quy trinh san xuat Idiang nguydn Soi Te bdo Vero kin 1 ldp
(3 ngay mdi)
. 1
Gay nhiem chiing Edmonston
Nudi 36 ± 1°C / 2-3 ngdy
, 1
Rua Hanks 3 lan, thay mdi ttudng (0%SR) Tiep tuc nudi 36 ± 1 C / 2-3 ngay Giir 4°C/qua dem i
1 Git
Ly tam lanh 3000 vdng / 20 phut, 4°C
Them chit bio quin