KHOA HOC Kt THUAT T H C Y TAP XX S 6 7 - 2013
TiNH HiNH fldniG NHIEM VA BOI N H I E M VI KHUAN TRONG CAC 0 DjCH ROI LOAN SINN SAN VA HO HAP THEN HEO GIAIOOAN 2011-Z01Z 6 CAN THO
Nguyen Dire Hien', Ho Thi Viet Thu^, Trtrffng Thf Kim Dung^, Juliet E. Bryant"
TOM TAT
Ket qua xet nghiem 26 mlu benh ph4m heo ducmg tinh v6i PRRSV cho thSy c6 sir hi8n dien cua cac yeu to gay b8nh khac la Pasteurella multoclda (65,38%), Porcine circovirus type 2 (38,46%), Haemophilus parasuis (34,61%), Actinobacillus pleuropneumoniae (30,76%i), dich ta heo (11,53%)) va khong phat hien dugfc Streptococcus suis type 2 trong mau kiem tra. Ket qua nay cho thay ti le heo chet cao trong cac 6 dich PRRS a Can Tha trong giai doan 2011-2012 c6 ihk la do tac dong cua mot so vi khuan va virus gay benh dong nhiem va/hoac bgi nhiem.
Sir dung khang sinh duoc xac dinh co hieu lire tren nhung vi khuan da phan lap dugc de can thiep vao cac 6 dich PRRS co the lam giam ti le tir vong dang ke 6 heo c6 dau hi8u benh. Trong do, qui trinh su dung ket hop tulathromycine va ceftiofur c6 the tang ti le hoi phiic a heo benh PRRS len den 87%.
Tir khoa: Heo, Roi loan sinh san va ho hap, Dong nhiem va boi nhiem, Kh^ng sinh.
Situation of the bacterial concurrent infection and superinfection in the outbreaks of Porcine Reproductive and Respiratory Syndrome (PRRS)
in the period 2 0 1 1 - 2 0 1 2 in Can Tho City
Nguyen Due Hien, Ho Thi Viet Thu, Truong Thi Kim Dung, Juliet E.Bryant
SUIUIMARY
Result of analysing 26 PRRSV positive pig specimens indicated that there was the presence of many other pathogens including Pasteurella multocida (65.38%), Porcine circovirus type 2 (38.46%), Haemophilus parasuis (34.61%), Actinobacillus pleuropneumoniae (30.76%) and Hog cholera virus (11.35%), whereas no Streptococcus suis type 2 was detected in the tested samples. This study result also showed the high mortality rate of pig In the PRRS outbreaks in Can Tho in the period 2011-2012 might be due to the effect of some bacteria and viruses caused concurrent infections and/or superinfections.
' Chi cue Thu y TP Can Tha
^ Bo mon Thu y, Khoa Nong Nghiep- Truong Bgi hoc Can Tha
^ Trung tam Thuyvung VII- TP.Can Tha
•* Oxford University Clinical Research Unit & Wellcome Trust Major Overseas Programme VN
KHOA HOC KV THUAT T H U Y TAP XX SO 7 - 2013
Using recommended antibiotics as an effective measure against these Isolated bacteria to interfere in PRRS outbreaks could significantly reduce the mortality rate in pigs having clinical signs of PRRS. Of which, procedure of using tulathromycine In combination with ceftiofur may increase the recovery of the PRRS infected pigs up to 87%.
Key words: Pigs, PRRS, Concurrent infection, Superinfection, Antibiotics
I. DAT VAN DE
Tir nSm 2007 den nay, hpi chirng roi loan sinh san va ho hap tren heo (RLSS&HH) x&y ra ngiiy cang nhi6u va gay thiet hai nghiem trong cho nganh ch3n nuoi heo a nuoc ta. Tai thanh pho can Tha (TPCT) n5m 2007 benh chi xay ra a 6 ho nuoi voi 102 heo b^nh thi den nSm 2010 dS xay ra a 698 hg/trang trai nuoi heo vcri 9.632 heo benh, trong do co nhieu ca so co ti le heo bj chet den 70% (Chi cue thii y TPCT. 2012). Mot s6 y kien cho rang heo mac hoi chiing RLSS&HH thuong dong nhiSm (co-infection) hoac bpi nhiem (superinfection) vai cac tac nhan gay benh khac nhu Actinobacillus pleuropneumoniae, Pasteurella multocida. Streptococcus suis.
Mycoplasma hyopneumoniae. Salmonella choleraesuis, Haemophilus parasuis^ Porcine circovirus, porcine respiratory coronavirus, va swine influenza virus v.v...(Nguyen Hijia Nam, Nguyin Thi Lan, 2007; Nguygn Van Cam va cs, 2011, Nguyin Tien Dijng, 2011). Cac tac gia nay da khuyen cao nen diing khang sinh de dieu tri bgi nhilm trong cac 6 dich RLSS&HH nh5m giam bat thiet hai gay chgt heo trong cac 6 dich.
Nghien cuu nay nham xac dinh sir hien dien cua mot so mam benh khac trong cac 6 dich RLSS&HH va thu nghiem sir dung mot so khang sinh de han chS muc do thiet hai do dich gay ra, gop them mgt giai phap hCai ich trong phong chdng djch RLSS&HH cho dan heo nuoi tai TR C5n Tha
II. NOI DUNG VA PHUONG PHAP NGHIEN CUU
2.1. Noi dung nghien cii'u
- Khao sat tinh hinh dich RLSS&HH tren dan heo a TPCT trong thai gian 2007- 2012
- Xac djnh ti 1? nhiem ciia mgt so mam b?nh khac trong cac 6 djch RLSS&HH a heo giai doan 2011-2012 tgi TPCT.
- Khao sat hieu qua cua can thiep khang sinh trong cac 6 dich RLSS&HH tai TPCT.
2.2. Phu'tfng ph^p nghien cuu
- Thu thap do lieu bang phucmg phap dieu tra hoi cuu tai 38 trai heo (100% so trai) va 585 ho chSn nuoi heo gia dinh (10%o so ho chan nuoi), cung nhu cac bao cao ve dich benh gia siic ciia thu y dia phucmg ghi nhan tir 2007-2011.
- Xet nghiem benh pham (mau, dich mieng, mui, phoi, gan, lach, than) thu thap tir 30 heo nghi benh RLSS&HH de xac dinh su hien dien cua PRRSV, virus djch ta heo. Porcine circovirus type 2, Pasteurella multocida. Streptococcus suis type 2, Haemophilus parasuis va Actinobacillus pleuropneumoniae.
- Lap khang sinh do tren cac chiing vi khuan phan lap hj heo co kk qua duong tinh PRRSV.
- Xay dung cac phac do dieu tri boi nhiem va danh gia ket qua ap dung it nhat cho 30 heo benh trong 6 djch RLSS&HH.
2.3. Cac k\ thuat diing trong \et nghiem va nffi thyc hifn
Cluin doan RLSS&HH: Phat hien PRRSV biing Realtime RT-PCR, sii dung Qiagen Rneasy minikit, Qiagen one-step RT-PCR va kit Invitrogen SS3 qRT-PCR. Xet nghiem dugc thuc hien tai Co quan thu y viing VII (TPCT) va Dan vi nghien ciai lam sang Dai hgc Oxford (Benh vien Nhiet dai TRHCM).
Chan doan benh dich ta heo: Thong qua phat hien khang nguyen pi25 b^ng ky thuat Indirect ELISA. Xet nghiem dugc thuc hien tai Co quan thu y vLing VI (TP HCM).
KHOA HOC K? THUAT THIJ Y TAP XX S 6 7-2013
Chan doan PCV type 2: BSng ky thu^it Realtime RT-PCR, su dung QIAamp DNA Blood Mini Kit va Qiagen Taq PCR Master Mix (Cat No.201443) hoac Invitrogen Pladnum PCR SuperMix (Cat No.l 1306-016). Xat nghiem dugc thuc hi?n tai Dcm vj nghien ciru lam sang Dai hgc Oxford (Benh vien Nhiet dai TRHCM) PhtSn Igp va giam dinh mot so vi khuan: dua theo tai lieu Clinical Veterinary Microbiology (2004) va Vien Ve sinh djch te Trung ucmg.
Thyrc hi^n tai khoa Nong nghiep & Sinh hgc ling dung, truong Dai hgc Ch\ Tha va Dan vj nghien ciiu lam sang Dai hgc Oxford (Benh vien Nhiet dai TRHCM)
Khang sinh do: Khao sit do man cam cua vi khuSn bgi nhilm vai 14 loai khang sinh bang phuang phap khulch tan tren dTa thach cua Kirby - Bauer (1966). Danh gia hieu lire ciia khang sinh dua vao tieu chuan cua fcLSl (Clinical And Laboratory Standards Institute,
2009). Khang sinh do thuc hi$n tai Bg mon thii y, khoa Nong nghi?p & Sinh hgc ling dung, truong Dai hgc Can Tho.
Thir nghiem can thiep khang sinh trong cac 6 dich RLSS&HH: do Phong Ky thu^t nghi?p vu Chi eye thii y TPCT ket hgp Tram thii y quan Binh Thuy, Cai R5ng, va Phong Qihn (TPCT) thuc hi?n.
Thai gian thuc hi?n: 6/2011 - 6/2012.
III. KET QUA THAO LUAN 3.1. Tinh htnh b$nh RLSS&HH trgn d^n heo TPCT
Ket qua dieu tra tinh hinh dich hoi chiing RLSS&HH tren heo nuoi 6 ngoai 6 TPCT trong giai doan 2007-2011 dugc tap hgp trong bang
1 va2.
Bang 1. Dien bien djch RLSS&HH tren dan heo TPCT tir 2007 -2011
So huy§n CO dich So dan xay ra benh So mic benh (con) So chet (con) T^ le chef (%)
2007 1 6 102
41 40,20
2008 5 111 1 976
929 47,01
2009 6 93 1.824 1 131 62,01
2010 9 698 9.632 5 224 54,23
2011 2 3 44 31 70,45
Ket qua dieu tra hoi ciiu cho thay dich RLSS&HH tren heo a TPCT xay ra vai miic do tang dan, ke ca pham vi tac dong cung nhu so lugng heo mSc benh va so heo bi chet. Tir 6 6 dich xiy ra tai 1 huyen voi 102 heo mac benh va 41 heo ch8t, chiem ty le 40,2% trong nam 2007 da tang den 698 6 djch xay ra a 9 quan huyen vdi 9.632 heo mkc benh va 5.224 heo bi chat, chigm 54,23% vao nam 2010. K8t qua nay phu hgp vai dien bien benh RLSS&HH o dan heo tai nhieu tinh thanh trong ca nude trong CLing thai gian. Nam 2007 co 14 tinh co dich vdi 70.577 heo benh, tang din den 2010 benh
da xay ra d 49 tinh thanh vdi 833.641 heo benh (Cue thuy, 2010).
S6 lieu hi bang 1 cung cho thay nam 2011, s6 6 dich va lugng heo mac b$nh giam dgt nggt chi con 44 heo benh, nhung ti 1| heo ch6t/s6 heo benh khong giam ma co chi^u hudng t3ng cao (70,45%). Viec giam nhe tinh hinh dich benh co the la do hieu qua cua cac phuong phap kilm scat dich benh ciia nganh thii y dia phuang kk hgp vdi tinh chu ky ciia benh, sau mgt dgt biing no dich benh thi nhieu heo dugc miln dich mang trimg nen dich tam ISng.
KHOA HOC K? THUAT THO Y TAP XX S6 7 - 2013
Tong hgp so li$u khao sat trong toan dgt dieu tra cho thky ti le heo nhilm b?nh d cac trang trai (44,73%) cao han d heo nuoi tai hg nuoi gia dinh (38,12%), mac dii sir sai khac nay khong y nghTa vh mat thdng ke (p>0,05). Tuy nhien trong dgt djch nSm 2010, theo bao cao tong kk cua Chi eye thu y TPCT, li I? heo chlt/b?nh 6 lo^i hinh chan nuoi tap trung cao han han heo nuoi qui mo gia dinh (74% so vdi 40%). Ket qua dieu tra tren cung phii hgp vdi ket qua dilu tra huyet thanh hgc thuc hi^n tren heo chua tiem vacxin PRRS tai TPCT ciia Nguyin Dire Hiln (2012), cho thay heo nuoi d trang trai cd ti I? duong tinh PRRSV cao han gip 5 l^n heo nuoi hg gia dinh (64% so vdi 12,45%). Tir ket qua nay c6 the dSn tdi nhan djnh qui mo chan nuoi cd anh hudng den su luu hanh ciia benh trong dan va
lam tang miic dg thi?t hai khi xay ra djch benh.
Dii nguyen nhan khdi ph^t la PRRSV, nhimg ti 1$ ch6t cao d heo trong cac 6 dich RLSS&HH d d^n heo can Tho con cd the do su ket hgp cua mgt s6 yeu t6 gay b?nh khac can dugc xac dinh.
3.2. IMOt s6 tdc nhan gSy b^nh dong nhiem v^
bOi nhiem tren heo RLSS&HH
De xic djnh sy hi^n di^n ciia mgt s6 mSm b?nh cd the dong nhilm va bgi nhilm tren heo nhiem b?nh RLSS&HH, trong thdi gian thuc hi^n de tai, chiing toi da thu thap b?nh pham tit 30 heo b?nh de chan doan xet nghiem PRRSV va mgt so b?nh co lien quan.
Ket qua xet nghi?m dugc trinh bay qua bang 2 v ^ 3 .
Bang 2. Ket qua xet nghiem PRRSV
Den vj
Binh Thuy Cai Rang Phong Dien Vinh Thanh Tho-i Lai T6ng Cong
M l u X N
5 7 7 6 5 30
lUau (t)
5 7 7 4 3 26
T y l f
(%)
100 100 100 66,67 60,00 86,67
Kieu gen Bic My
Chung co dien (+)
1 2 1 0 0 4
(%)
20,00 28,57 14,29 0 0 15,38
B i c M y chijng Trung Qu6c
(+) 4 5 5 4 3 21
(%)
80,00 71,43 71,42 100 100 80,76
Kieu gen k4t hgp (+)
1
1
(%)
14,29
2,78
Ket qua d bang 2 cho thay 26/30 mlu heo duoc xac dinh la ducmg tinh vdi PRRSV bang ky thuat Realtime RT-PCR, chiam ty le 86,67%.
Trong so nay, su hien dien cua kieu gen Bac My chiem 100%, trong dd kieu gen Bac My dong Trung Quoc chiem 80,76%, kieu gen Bac My chung cd dien 15,38%, kieu gen ket hgp BSc My CO dien va Bac My dong Trung Quoc chiem ti le 2,78%. Ket qua nay phii hgp vdi cong bo ciia Nguyen Nggc Hai va Vo Khanh Hung (2011), khi xet nghiem mau benh pham tren heo tai TP.
HCM, DongNai, Ba Ria-VOngTau, BSc Giang va Ha Noi trong 2 nam 2010 -2011 da phat hien
PRRSV kieu gen Bac My chiem 100% so mau, trong khi do kieu gen chau Au chi 2,18% va cung la mau nhilm ghep vdi kieu gen Bac My CO dien. Ciing thdi gian do, Nguyen Thi Cam Hang (2011), khi dinh genotype PRRSV gay benh tai dan heo Bac Lieu va Soc Trang ciong ghi nhan ti le nhilm PRRSV kieu gen Bac My chilm tile 100% (106/106).
Bang phucmg phap so sanh trinh tu nucleotid doan gen ma hoa protein gP5 da xac dinh chung PRRSV gay benh tren dan heo CSn Tha tuong tir chiing Bac My bien doi gen cd dgc luc cao
KHOA HOC KY THUAT T H O Y TAP XX S 6 7 - 2013
xuat hien vAo nam 2007 da tCrng gay b?nh cho han 2 tri6u heo tai 10 tinh cua Trung Qudc vdi so heo chet len den han 400.000 con. Chinh viec nhilm chiing PRRSV dgc luc cao nay da giai thich cho s6 heo mSc benh RLSS&HH chet nhieu tai TPCT. Nghien ciiu cua Youn Feng et al, (2009) cdng bo rang cac chiing gay
b^nh trong cac 6 dich RLSS&HH tai Viet Nam va Trung Qudc nam 2007 c6 bg gen tuong ddng gSn 99%, diu mdt mgt doan acid amin tren protein khong cau tnic sd 2 chirng td rang cac bien chiing virus xuat hi$n tai Vi?t Nam va Trung Qudc la dong nhat.
Bang 3. Ket qua xet nghiem tac nhSn d6ng nhiem trong b^nh phim heo RLSS&HH
Bon vj Binh ThOy
Cdi Rang Phong Gt^n Vfnh Thanh Th*i Lai T6ng c^ng
S6m§u 5 7 7 4 3 26
Kit qua xet nghiem DTH
0 1 1 1 0 3
PCV-2 3 3 2 1 1 10
PI/I 3 5 6 2 1 17
S S - 2 0 0 0 0 0 0
APP 2 3 2 1 0 8
HP 1 4 3 0 1 9 DTH: Dich td heo.
PM: Pasteurella multocida.
APP: Actinobacillus pleuropneumoniae.
PCV 2 : Porcine circovirus type 2 S.S-2: Streptococcus suis serotype 2 HP- Haemophilus parasuis
So lieu d bang 3 cho thay su hien dien cua vi khuSn Pasteurella multocida a heo benh PRRS chilm ti le cao nhSt (65,38%). Ket qua nay phii hgp vdi nghien cihi ciia Brockmeier et al (2001), cho rang Pasteurella multocida song tilm tang trong he ho hip, khi heo nhilm PRRSV hay B.
bronchiseptica se de dan tdi nhiem triing phoi thu cap vdi Pasteurella multocida. Nghien cihi cua Carvalho et al, (1997) ciing bao cao rSng Pasteurella multocida la vi khuSn gay b?nh quan trong khi heo nhilm b8nh RLSS&HH.
Trong khao sat cua chiing toi, vdi ti le phat hien Pasteurella multocida len den 65,38%, trong khi ti le tiem phong vacxin tu huyet triing tren dan heo hang nam dat ti le thap, chi khoang 20% tdng dan (Chi cue thii y TPCT, 2012), nen nguy ca heo chSt do tac dong ciia Pasteurella multocida trong cac 6 dich RLSS&HH la rk Idn.
YJX qua xet nghi?m ciing cho thiy Porcine circovirus type 2 hien dien vdi ti le cao (38,46%) d nhiing heo cd hoi chiing RLSS&HH. Ti le
nay tuy thap hem so vdi mdt s6 tinh d Mien Dong la 64,71% (Lam Thi Thu Huong, 2012), nhung do hau hit cac ca sd chan nuoi tai TPCT deu khong tiem vacxin phong benh do Porcine circovirus type 2 (Chi cue thii y TPCT, 2012), cho nen nhan xet ve so heo mac benh RLSS&HH chet nhilu, dac bi?t la heo sau cai sura, chiing tdi cho la ciing cd phAn la do tac dong cua mam benh nay.
Ti le nhiem Haemophilus parasuis va Actinobacillus pleuropneumoniae trong khao sat cua chiing toi lan lugt la 34,61% va 30,76%, cao han sd lieu cua Le Van Ducmg va cdng su khao sat nam 2011 tai Bac Giang (19,59%) nhung tuang duong vdi khao sat cua Dang Xuan Binh va cdng su nam 2007 t?i Thai Nguyen va Ha Tay (31,25%).
Trong ket qua khao sat cua chiing tdi, virus dich ta heo hiSn dien vdi ti 18 thap (11,53%).
Dieu nay phu hgp thuc tl vi cac bi$n phap phong benh dich ta rat dugc chu trong tren dan
KHOA HQC KY THUAT T H O Y TAP XX S 6 7 - 2013
heo t^i TPCT. H^ng nSm ti le tiem phdng vacxin djch ta heo dat 70,6% tong dan. chiem ti 1? cao nhat trong cac lo^i vacxin dugc tiem phong tren dan heo (Chi eye thu y TPCT, 2012). Dii kit qua mgt so thi nghi?m cho rJing PRRSV sg \km giam hi$u qua ciia vacxin djch ta heo do lic che kha nang tao d^p irng miln dich (Ning Yi -bao et al, 2011). Tuy nhien, tir ket qui xdc djnh ti I? luu hanh PRRSV tren dan heo tai TPCT nam 2011 chi cd 16,9 % (Nguyin Diic Hiln va cs, 2012), thap hon nhieu so vdi sd li?u da cdng bd tren dan heo d tinh thanh khac trong ca nude la 82,6%
(Nguyin Van Cam v^ cs, 2011), c6 thi dua tdi nhan xet rang hi?u qua tiem chiing vacxin dich ta heo khong bi anh hudng nhieu tren dan heo tai TPCT bdi PRRSV. Kit qua xet nghiem tren ket hgp ti le tiem phong dich ta heo dat ti le cao cho thay trong cdc d dich RLSS&HH, bgi nhilm va dong nhiem do dich ta heo cd nguy ca thap nhat trong cac loai mam benh dugc khao sat.
Streptococcus suis serotype 2 la mot can nguyen gay benh cd dgc luc cao tren heo va cd kha nang lay nhilm sang ngudi, gay viem mang nao va nhilm triing huyet. Cd nhieu bang chiing cho thay vi khuan nay hien dien phd bien d heo nhilm PRRSV va ciing la nguyen nhan tir vong d heo b8nh (Thanawongnuwech, 2000), Tai Viet Nam, sd ngudi nhiem va hi vong do Streptococcus suis serotype 2 tang cao trong cac nam 2007, 2009 va 2010 ciing luc vdi biing phat ciia hoi chung RLSS&HH trong nude (Ngo Thi Hoa et al, 2013), cd the cd lien quan den tieu diing thuc pham cd nguon gdc tir heo nhilm benh, dac bi?t la tap quan su dyng tilt canh heo d mot sd dja phuang. Tuy nhien qua xet nghiem cac mlu benh pham tir 26 heo da dugc xac dinh la duong tinh vdi PRRSV, chung tdi da khong phat hien dugc Streptococcus suis type 2. Ket qua nay cung phii hgp vdi Nguyin Tiing (2010), khi phan lap vi khuSn tir cac d djch RLSS&HH tren heo d cac tinh phia Nam cho thay Streptococcus suis type 2 xudt hien vdi ti rk thSp (2,1%). Nghien cuu vl su dong
nhiem ciia Streptococcus suis type 2 tren heo RLSS&HH d 3 tinh Thai Binh, Tiln Giang va Sdc Trang, Ngo Thi Hoa et al (2013) cung bao cao ti 1? nhiem Streptococcus suis type 2 tren heo b?nh chi cd 1,7% (9/534). Tir kit qua xet nhi&n tren, chung tdi nhan xet rang Streptococcus suis type 2 khong phai la vi khuan dong nhilm pho blln tren heo mac h^i chirng RLSS&HH d Tp Can Tho trong thdi diem khao sat. Ket qua nay cung phii hgp vdi thuc te Ik khong xay ra truong hgp ngg dgc thuc pham hay bj nhiem benh do Streptococcus suis type 2 cua cu dan TPCT trong sudt qua trinh xay ra dich RLSS&HH d dan heo trong tinh.
Ket qua xet nghigm cd the phy thugc vao tinh hinh djch te ciia moi dia phucmg, loai mau cung nhu thdi diem lay mau. Tuy nhien vdi ti le hien di?n kha cao ciia mgt sd nhan td gay benh dong nhiem cd the do tac dong lam huy hoai cac dai thyc bao d phe nang heo cua PRRSV da dan tdi suy giam nghiem trgng he thong mien dich, tir do lam cho heo de bgi nhiem mgt sd loai virus va vi khuan, trong dd ndi trgi len trong khao sat ciia chiing tdi la P. multocida, H parasuis, A. pleuropneumoniae va PCV-2.
Chinh su nhilm ciing liic nhieu tac nhan gay benh dan tdi dau hieu dien hinh ciia mgt so benh bi thay doi, lam cho chan doan lam sang trdnen khd khan hon. Mgt sd ket qua nghien ciiu khac cung thong nhat rang PRRSV tac dong gay pha hiiy cac dai thuc bao ngi mach phoi va dai thuc bao phe nang phoi, do dd heo rat dl mic benh viem phdi do vi khuan va nhiem triing huyet (Thanawongnuwech et al, 2000).
Tir ket qua xac dinh cac yeu to gdp phan lam tram trgng them tinh hinh dich benh RLSS&HH trong cac dgt dich vira qua tren dan heo d Tp Can Tha, chiing tdi nhan dinh rang de giam thiet hai khi heo nhilm PRRSV, viec su dung khang sinh de kiem soat va tieu diet mgt so tac nhan gay b?nh ddng nhiem va bgi nhilm la viec het siic can thiet nhu mgt sd nha nghien cuu trong va ngoai nude da tirng de xuk.
KHOA HQC KY T H U A T T H O Y TAP XX S 6 7 - 2013
3.3. Thu- nghifm kha nang can thiep khang sinh v^o cdc 6 dich RLSS&HH
3.3.1. Kit qua khang sinh do tren mgt sd vi khuan phan lap tir heo benh
De xac dinh khang sinh thich hgp cd the
su dung trong cac d dich RLSS&HH, khang sinh do cua 3 lo^i vi khuan {P. multocida, H.
parasuis, A. pleuropneumoniae) tir cac d dich da dugc thuc hien vdi 14 loai khang sinh thdng dyng. Ket qua dugc trinh bay d bang 4.
Bang 4. Ket qua khang sinh do tren vl khuan phan lap tu" heo RLSS&HH
Khang sinh Ceftiofur Tilmicosin Gentamycin Doxycycline Spiramycin Enrofioxacin Amoxiciilin Cefalexin Streptomycin Erythromycin Marbofloxacin Florfenicol Sulfa/ Trime Tulathromycin
Ti le (%) m i n cam tren c i c ioai vi khuin khao sat (*) P.multocida
(n =)7J Nhay
85 19 63 81 19 76 19 84 19 21 78 75 21 79
IB 6 0 13 13 31 6 47 10 38 29 10 13 41 15
Khang 9 81 24 6 50 18 34 6 43 60 12 12 38 6
A. pleuropneumoniae (n'8) Nh^y
83 56 50 64 67 43 63 67 17 66 70 67 17 83
TB 17 38 33 31 17 23 19 28 17 19 23 24 19 17
Khang 0 6 17 5 16 34 18 5 66 15 7 9 64 0
H. parasuis ln=9) Nh^y
89 78 67 74 70 67 56 89 44 69 89 82 22 89
TB 11 22 22 26 22 19 12 11 22 20 11 13 11 11
Khing 0 0 11 0 8 14 32 0 34 11 0 5 67 0
* Danh gia ket qua theo CLSl -2009 Ket qua khang sinh dd the hien d bang 4 cho thay nhihig khang sinh cd do nhay cao ciing Iiic vdi 3 loai vi khuan dugc khao sat lan lugt la ceftiofiir (85%, 83%, 89%), cefalexin (84%, 67%, 89%), tulathromycin (79%, 83%, 89%) va marbofloxacin (78%, 70%, 89%). Mgt so khang sinh khac chi cd tac ddng tren 1 hoac 2 loai vi khuan gay benh nhu gentamycin, spiramycin, tilmicosin... Ket qua khang sinh dd d tren ciing cho thay 3 vi khuan khao sat c6 ti le khang cao vdi streptomycine hoac cong thirc phdi hgp sulfa/ trimethroprim.
De dieu tri benh bgi nhiem trong cac 6 dich RLSS&HH, nhieu tac gia de nghi sii dung
mgt sd khang sinh nhu ceftiofur (Nguyen Tien DQng, 2011), lincomycin, spectinomycin (Le Van Nam, 2007) v.v... hoac bd sung khang sinh penicilline, oxytetracycHne, terramycin, hon hgp trimethroprim/ sulfamid nhu la mgt loai premix vao khau phan de khong che vi khuan co hoi ngan ngira bgc phat PRRS (The Pig Site, 2012). Tuy nhien qua ket qua khang sinh dd nay cho thay mgt sd khang sinh dii c6 tac dung manh vdi loai vi khuan nay nhung lai tac dung thap doi vdi vi khuan khac, vi dy nhu H. parasuis dii con kha nhay vdi tilmicosin (78%) nhung Pmultocida lai de khang cao ddi vdi khang sinh nay (81%). Ngoai ra, hieu luc
KHOA HQC KY THUAT THU Y TAP XX S 6 7 - 2013
ciia mdi lo^i khang sinh tren tirng vi khuan c6n phy thugc vao d$c tinh khang thudc ciia chiing vi khuan gay b?nh tai thuc dja, vao loai khang sinh thudng su dyng cung nhu cAch sir dyng d tirng dia phuang, tirng trang tr^i chan nuoi. Do v^y dl sir dyng khang sinh cd hi?u qua thi vi^c thyc hi?n kh^ng sinh dd ddi vdi vi khuan gay b?nh la rat can thiet.
3.3.2. Kit qua dieu trf b?nh bgi nhiem tren heo RLSS&HH
Tir kit qua phan lap vi khuSn va ket qua khdng sinh do d tren, chiing tdi uu tien chgn khang sinh cd dg nhay cao ddi vdi vi khuSa Pasteurella multocida, la vi khuSn dugc xuk hi?n nhilu nh5t trong cdc mlu xet nghiem dl xay dung phac dd dieu trj. Ket qud dilu tri dugc trinh bay trong bang 5.
Bang 5. Phac do dung khdng sinh can thiep vdo 6 djch RLSS&HH Phac ah
1 2 3 4 5
Khdngsinh sir dyng Tulathromycin Ceftiofur
Doxycyclin + Florphenicol Tulathromycin
Ceftiofur Tulathromycin Doxycyclin + Florphenicol
Qui trinh su- dyng
Ti§m bap 2,5mg/kgP. ti§m 1 li^u duy nh^t trong sudt qua trinh 6\ku tn.
Ti6m b i p 5mg/kgP, ngSy 1 l^n. trong 3 -7 ng^y
TiSm b^p h6n hgp Doxycyclin 10mg/kgP + Florphenicol 20mg/
kgP, ngay 1 l l n , trong 3 - 7 ngay.
- Ng^y 1: TiSm bap Tulathromycin 2,5mg/kgP, 1 li^u duy n h i t . - Ngay 2 : tiem Ceftiofur lieu 5mg/kgP, ngay 1 \kn, trong 3-7 ngay - Ngay 1: TiSm bap Tulathromycin 2.5mg/kgP, 1 lieu duy nhat.
- Ngay 2: Ti6m bap Doxycyclin lOmg/kgP + Florphenicol 20mg/
kgP, ngay 1 l^n, trong 3 - 7 ngay.
Ca 5 phac do tren deu cd sir dyng cac thudc ho trg dieu tri trieu chiing (Igi tieu, long dam, giam ho) va vitamin de tang sue de khang (vitamin C, nhdm B), khang viem (neu trong san pham dieu tn khong cd ket hgp san vdi khang viem). Heo
dieu tri benh dugc each ly triet de, ve sinh sat triing chudng trai 2 lan/ngay.
Sau day la ket qua ghi nhan dugc trong qua trinh dieu tri thuc te tai mgt sd hg chan nuoi heo da xay ra hgi chung RLSS&HH.
Bang 6. Ket qua dieu trj cac trui^ng hp'p heo b^nh PRRS
Phic 06 1 2 3 4 5
So ca dieu tri 7 8 6 8 9
Sd i3ilu tri kh6i (1)
5 6 4 7 7
Ti l# kh6i
(%)
71,43 75.00 66,66 87,00 77,78
So ngay dieu tri trung binh
6 5 7 5 6 (l)Khi heo khong con bieu hien tam sang cua benh va an uong, sinh hoat tra lai binh thirangse danh gid la khoi benh va ngung dimg thuoc. Sau 7 ngay ditng thuoc, nhirng heo khong khoi benh sexir ly giet hiiy theo qui dinh.
KHOA HQC KY THUAT T H O Y T A P X X S 6 7 - 2013
Ket qua the hien d bang 6 cho thSy khi cd can thiep bang khang sinh phii hgp thi se lam giam ti le chet dang kl cho dan heo m^c benh d tat ca cac phac dd dieu tri da sii dung. Trong do, phac dd dilu tri 4 (tulathromycin ket hgp ceftiofur) cd th6 lam tang ti le khoi benh den 87% (7/8 heo dugc dieu tri). Ket qua nay cung phu hgp vdi dugc luc hgc va dugc dgng hgc cua cac khang sinh sii dung. Tulathromycin (khang sinh nhdm Macrolid) la mgt khang sinh mdi, chuyen dimg trong thii y, dugc xac dinh la co hieu lire rat cao tren dieu tri benh dudng hd hap d heo do thuoc cd thdi gian ban thai rat dai d phoi (142 gid) va nong dg thudc tap trung d phdi cao gap 61,4 lan so vdi ndng do thuoc trong huyet tuong (Benchaoui et al, 2004). Tuong tu nhu vSy, Ceftiofur thugc the he thir 3 ciia phan nhdm cephalosporin (nhdm betalactam).
Cling la mgt khang sinh chuyen dimg trong thii y cd phd tac dyng rat rdng tren ca vi khuan gram duong va gram am, dugc dimg chu yeu trong dieu tri benh dudng hd hap d gia siic do P. multocida, H. parasuis, A. pleuropneumoniae va Streptococcus suis cho hieu qua rat tot.
D I loai trir triet dl PRRSV khoi dan, hien nay d nhieu quoc gia cd nen chan nuoi cdng nghiep phat tnen, heo benh va heo tiep xiic vol mam benh deu bi giet huy ddng thdi vdi viec ap dung cac bien phap ve sinh thii y va kiem dich chat che de xay dimg dan heo sach benh.
Tuy nhien trong dieu kien thuc te tai Viet Nam, hinh thiic chan nuoi phan tan, nho le con chiem ti le cao trong tong dan, chiing tdi cho rang viec can thiep khang sinh vao d dich RLSS&HH la can thiet de giam ti le thi6t hai cho ngudi chan nuoi. Ngoai tac dgng di8t khuin, mot sd nghien ciiu truoc day da chiing minh rang trong mgt sd trudng hgp, mgt sd thudc khang sinh co the cd tac dung khang virus (Subak-Sharpe et al, 1969).
Nghien cihi vl tac dung cua khang sinh ddi vdi PRRSV, nam 2001, Molitor et al, phat hien rang tilmicosin (khang sinh nhdm Macrolid) tiiy theo lilu lugng sii dung cd tac dung lic chi kha nang sao chep cua PRRSV tren mdi trudng tl bao dai thuc bao phi nang (PAMs). Nam 2008, William phat hien khang sinh nalidixic acid va
ciprofloxacin (nhdm Quinolone) cd tac dung lic chi su sao chep nhan ban ciia PRRSV trong mdi trudng tl bao MARC-145 va mdi trudng dai thuc bao phi nang. Ciing trong nam nay (2008), Stuart et al cdng bd rang tylvalosin (khang sinh nhdm Macrolid) cd tdc dgng lic chi ca 2 chung PRRSV BSc My va chau Au trong mdi trudng nuoi cay. Gh\ day, Du Y et al. (2011) cung bao cdo rang khang sinh tilmicosin c6 tac dyng lie chi ca 2 type PRRSV nhan ban trong mdi trudng dai thuc bao phi nang, va tdc gia cho rang tilmicosin c6 the sir dung dieu tri sdm hoac su dyng nhu la bi?n phap phong ngira chdng lai su nhilm PRRSV, dac biet la doi vdi nhiing khu vuc cd kieu gen chau Au pho bi6n. Nhiing phat hien nay gdp phan ciing co cho phucmg phap sit dung khang sinh trong cac d dich RLSS&HH, bdi vi ngoai dieu tri bSnh bgi nhiem, ban than khang sinh ciing gdp phiin trong viec ire che nhan ban cita PRRSV, giiip cho heo mau binh phuc hon.
Trong qui dinh ve phong chdng hgi chiing RLSS&HH ban hanh theo Quylt dinh sd 80/2008/QD-BNN ngay 15/7/2008 cua Bd trudng Bp Ndng nghiep va Phat tnen ndng thdn ciing hudng dan: khi xay ra benh RLSS&HH d dien rdng thi chi tieu hiiy heo benh khi da cham soc tich cue va hd trg tang cudng siic de khang trong vong 7 ngay nhung khong cd kha nang binh phuc. Do do kit qua thi nghiem nay la ca sd khoa hgc cho dieu tri benh bgi nhiem d heo mac hgi chiing RLSS&HH khi cd di6u kien thuc hien (d dich da lan rdng, dieu kien each ly cham sdc tot) nham giam ton that cho ngudi chan nudi.
V I . K E T L U A N
Cac mam benh, bao gom Pasteurella multocida, Haemophilus parasuis, Actinobacillus pleuropneumoniae, vims dich ta heo va PCV-2,
la nhung tac nhan gay benh ddng nhiem va bgi nhilm da dugc phat hien tren heo benh RLSS&HH tai TR Cin Tho. Trong dd, P multocida hien dien vdi ti le cao nhat (65,38%), ke den la Porcine circovirus type 2 (38,46%),
KHOA HQC KY THUAT THC Y TAP XX S 6 7 - 2013
H. parasuis (34,61%), A. pleuropneumoniae (30,76%). Djch ta heo xu^l hi?n vdi ti I?
thap nhat (11,53%) va khong phat hign dugc Siivpiococcus suis type 2 trong cac mau xet nghi?m. Ket qua nay cho thay yeu td gay chet heo vdi li I? cao trong cac o dich RLSS&HH d TP.Can Tha cd phSn tac dgng cua vi khuan va virus gay bgnh ddng nhiem vk bgi nhiem, trong do quan trgng nhat la P. multocida.
Sir dyng khang sinh cd dg nhay cao iren vi khuan phan lap de can thi^p vao cac d djch RLSS&HH da lam giam ti Ig tu vong dang ke d nhirng heo cd dau higu b?nh. Trong dd, qui trinh su dung ket hgp 2 loai khang sinh la tulathromycin va ceftiofur cd the tang ti I? hdi phyc a heo benh PRRS len din 87%.
TAI L I E U T H A M K H A O 1. Dang Xuan Binh, Nguyen Thi Ngan,
Phan Hdng Phiic (2007). Tinh hinh nhilm Actinobacillus pleuropneumoniae va b?nh viem phdi - mang phdi d Ign. Tap chi Khoa hoc ley thuat thu y tap XIV sd 2-2012, tr 56-59.
2. Lam Thi Thu Huong (2012), Benh tich va ti le nhiem mgt s6 vi khuan cong nhiem tren heo mac hgi chimg gay com sau cai sCia.
Tap chi Khoa hoc ky thugl thu y tap XIX s6 3-2012, tr 26-32
3. Le van Duong, Nguyin Quang Tuyen, Cii Hiju Phu, Hoang Dang Huyin (2012). Ket qua phan lap va xac dinh mgt so dac tinh sinh vat hgc ciia cac chiing Actinobacillus pleuropneumoniae a Ign duong tinh vdi virus PRRS tai tinh Bac Giang. Tap chi Khoa hoc ky ihiidl thit y, tap XIXs6 3-2012.
tr 45-50.
4. Nguyin Tiln Dung (2011). Nhimg van de thai su ve Hgi chirng rdi loan sinh san \ a hd hap ciia Ign (PRRS hay bgnh Ign tai xanh).
Tap chi Khoa hoc ky thuat thu y. tap XVIII sdl-201I.tr 5-II.
5. Nguyin Van Cam, Nguyen Tiing, Nguyen Dang Thg, Tdng Hiru Hiln va cs (2011).
Dieu tra su luu hanh hgi chiing rdi loan sinh san va hd hap (PRRS) tren dan Ign mgt sd tinh d Vigt Nam. Ti^p chi Khoa hoc ky thuat ihii y tap XVIII sd 1-2011. tr 21-30.
6. Nguyen Diic Hien va cs (2012), Tinh hinh nhiem Hgi chimg rdi lo^n sinh san va ho hap tren heo (PRRS - Porcine Reproductive and Respiratory Syndrome) va xay dyng qui trinh phong trj benh thich hgp tai thanh phd Can Tho. Bao cao tdng ket de tai nghien ciru khoa hgc cap thanh phd. Sd Khoa hpc va cdng nghe TP.Can Tha - 6.2012.
7. Nguyin Nggc Hai, Vd Khanh Hung (2011), Tinh da dang kieu gen virus PRRS nhiem tren mgt sd dan heo nudi. Tap chi Khoa hgc ky thuat thu y tgp XIX s6 1-2012. pp 20-28.
8. Nguyen Hun Nam, Nguyen Thi Lan (2007), Hgi chimg rdi loan sinh san va ho hap (PRRS). Tai lieu hgi thao khoa hgc, Khoa thu y, Trudng Dai hgc Ndng Nghiep I, Ha Ngi,tr 11-24
9. Youn Feng, Tiezhu Zhao, Nguyin Tiing, Ken Inui, Ying Ma. Nguyin Thi Hoa, Nguyen Van Cam, Di Lui. Biii Quang Anh, Td Long Thanh. Chuabin Wang, Kegong Tian va Georfe F.Gao (2009), "Cac biln chung \'irus gay PRRS tai Viet Nam va Trung Qudc nam 2007", Tgp chi Khoa hoc AT thutSt thii y. tap XVI so 1-2009. pp 5-9 10. Benchaoui HA, Nowakovi'ski MA,
Shenngton J, e/a/(2004). Pharmacokinetics and lung tissue concentrations of tulathromycin in swine. J Vet Pharmacol Ther 2004: 27:203-210
11. Brockmeier S. L., Palmer M. V, Bolin S.
R., Rimler R. B (2001). Effects of intranasal inoculation with Bordetella bronchiseptica, porcine reproductive and respiratory syndrome virus, or a combination of both organisms on subsequent infection with
KHOA HQC KY THUAT T H C Y TAP XX SO 7 - 2013
Pasteurella multocida in pigs. Am. J. Vet.
Res. 2001; 62:521-525.
12. Carvalho LFOS, Segales J, Pijoan C.
(1997), Effect of porcine reproductive and respiratory syndrome virus on subsequent Pasteurella multocida challenge in pigs .
Vet Microbiol 55-241-246.
13. Du Y, Yoo D, Paradis MA, Scherba G (2011) Antiviral Activity of Tilmicosin for Type 1 and Type 2 Porcine Reproductive And Respiratory Syndrome Virus In Cultured Porcine Alveolar Macrophages. J Antivir Antiretrovir 3: 028-033.
14. MolitorTW, Bautista E, Shin JH, McGruder ED, Ambruster GA (2001) Tilmicosin affects porcine reproductive and respiratory syndrome virus replication. Proc Allan D Leman Swine Conference p31.
15. Ning Yi-bao, Zhao Yun, Wang Qin et al (2012), Influence of PPV, PRV and PRRSV on Efficacy of the Lapinized Hog Cholera Vaccine and Pathogenicity of Classical swine fever virus. Journal of Integrative Agriculture. 2012, 11(11): 1892-1897.
16. Nutsch RG, Hart FJ, Rooney KA, et al (2005). Efficacy of tulathromycin injectable solution for the treatment of naturally occurring swine respiratory disease. Vet Ther 2005;6(2) :2I4-224.
17. Ngo Thi Hoa,Tran Thi Bich Chieu, Sam Do Dung, Ngo Thanh Long, Thai Quoc Hieu, Nguyen Tien Luc, Pham Thanh Nhuong,
Vu Thi Lan Huong, Dao Tuyet Trinh, Heiman F.L. Wertheim, Nguyen Van Kinh, James 1. Campbell, Jeremy Farrar, Nguyen Van Vinh Chau, Stephen Baker, and Juliet E. Bryant. Streptococcus suis and Porcine Reproductive and Respiratory Syndrome, Vietnam. Emerg Infect Dis. 2013 February:
19(2): 331-333.
18. Stuart AD, Brown TDK, Mockett APA (2008) Tylvalosin, a macrolide antibiotic, inhibits the in-vitro replication of European and American porcine reproductive and respiratory syndrome (PRRS) viruses. Pig J 61.
19. Thanawongnuwech R., Brown G B,,Halbur P. G., Roth J. A,, Royer R. L., Thacker B. J. (2000), Pathogenesis of porcine reproductive and respiratory syndrome virus-induced increase in susceptibility to Streptococcus suis infection. Vet. Pathol.
2000:37-143-152
20. William A. Cafrunyl, Richard G. Dumanl, Raymond R. Rowland2, Eric A. Nelson and Grace H. Wong (2008). Antibiotic-Mediated Inhibition of Porcine Reproductive and Respiratory Syndrome Virus (PRRSV) Infection: A Novel Quinolone Function Which Potentiates the Antiviral Cytokine Response in MARC-145 Cells and Pig Macrophages. Virology Research and Treatment 2008:1 17-28.
Nhan ngay: 21/5/2013 Ngay phan bien: 15/7/2013
CANH GIAC CUM GIA CAM H5N1 T^I BIEN GIOI CAMPUCHIA Chi cue thii y TRHCM vira dua ra canh bao, tai Campuchia da co 17 ca nhilm virus cum gta cSm H5N1, trong dd 10 ngudi tu vong do tiep xuc vdi gia cam benh, chet. Dieu dang ngai la co nhieu truong hgp xay ra d cac tinh kha gan vdi bien gidi phia lay nam va dong nam nirdc ta nhu Kampot, Takeo, Preyveng, Kandal...
Dk chu dgng ngan chan, Chi cue thu y TP.HCM da tang cudng tap trung lye lugng kilm tra, xir ly viec vSn chuyen, giet mo, kinh doanh gia sue, gia cam trai phep, dac biet la tai cac Tram kiem dich dau mfii giao thong, cira ng5 ra vao thanh pho.
Biii Nguyen (7/10/2013)
