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NATIONAL INSTITUTE OF VETERINARY RESEARCH ENTERIC DISEASES DIAGNOSTIC REQUEST FORM NIVR Use Only: TEST FARM NUMBER: LABORATORY SUBMISSION NUMBER: Contact details of person collectin

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NATIONAL INSTITUTE OF VETERINARY RESEARCH

ENTERIC DISEASES DIAGNOSTIC REQUEST FORM

NIVR Use Only:

TEST FARM NUMBER:

LABORATORY SUBMISSION NUMBER:

Contact details of person collecting specimen:

Name: Occupation:

Address:

Province: Postcode:

Telephone: Fax: Email:

Foster pigs

Number of piglets with diarrhoea

Duration Sample type Treated?

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NATIONAL INSTITUTE OF VETERINARY RESEARCH

ENTERIC DISEASES DIAGNOSTIC REQUEST FORM

Signed ……… Date………

Characteristics of faecal specimens:

Sample No: pH: Colour: Consistency (Scale

Diagnosis

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NATIONAL INSTITUTE OF VETERINARY RESEARCH

ENTERIC DISEASES DIAGNOSTIC REQUEST FORM

Signed ……… Date………

Trang 15

1

Pre-weaning diarrhoea in pigs (PrWD) is a complex

problem involving a large number of causative agents:

transmissible gastroenteritis virus (TGEV), rotavirus

(RV), enterotoxigenic E coli (ETEC), Clostridium

perfringens (C per.), coccidiosis due to Isospora suis

(Cocci), and Cryptosporidium (Crypto) [1]

The predominant causes of PrWD and their relative

contribution to morbidity vary between countries, and

have continuously changed over time, due to the

adoption of new management practices and the

emergence of new diseases In addition, some

pathogens are restricted to certain geographical

locations [2]

A comprehensive survey of the major causative agents

of PrWD has not been attempted previously in Vietnam

CAUSES OF PRE-WEANING DIARRHOEA IN COMMERCIAL

AND VILLAGE PIGS IN VIETNAM

Do NT 1 , Nguyen XH 1 , Au XT 1 , Cu HP 1 , Fahy VA 2 , Cargill C 3 , and Trott DJ 4

1 National Institute of Veterinary Research, Hanoi, Vietnam

2 National E coli Reference Laboratory, Department of Natural Resources and Environment, Epsom, VIC 3554, Australia

3 The South Australian Research and Development Institute (SARDI), Adelaide SA 5001, Australia

4 School of Veterinary Science, The University of Queensland, Brisbane, QLD 4072

Table 1: The contribution of different infectious agents to

PrWD in commercial and village pigs

# of positive specimens (%) Agent(s) detected

45 (100.0)

92 (78.8) Total multiple infections

(23) (76) (111) (97) (50) (36)

1 (0.8)

C per.

ETEC TGEV RV Crypto

1 (2.2)

1 (0.8)

C per.

TGEV RV Crypto Cocci

1 (2.2)

4 (3.4) ETEC

TGEV RV Cocci

1 (0.8)

C per.

TGEV Crypto

Cocci

1 (2.2)

1 (0.8) TGEV

RV Crypto Cocci

2 (4.4)

1 (0.8)

C per.

ETEC RV

Crypto

1 (2.2)

2 (1.7) ETEC

TGEV RV Crypto

2 (1.7)

C per.

ETEC TGEV

3 (6.7)

2 (1.7)

C per.

ETEC RV

1 (2.2)

1 (0.8)

C per.

TGEV RV

7 (15.6)

14 (11.9) ETEC

TGEV RV

3 (2.5) TGEV

RV Crypto

1 (2.2)

1 (0.8)

C per.

TGEV Crypto

3 (6.7)

1 (0.8) ETEC

RV Crypto

4 (4.4)

5 (4.2) ETEC

TGEV Crypto

1 (2.2)

1 (0.8) RV

Crypto Cocci

2 (4.4)

2 (1.7) ETEC

TGEV Cocci

3 (6.7)

4 (3.4) TGEV

RV Cocci

3 (6.7)

2 (1.7) ETEC

RV Cocci

7 (5.9) ETEC

Crypto

2 (4.4)

1 (0.8) Crypto

Cocci

2 (4.4)

1 (0.8) RV

Cocci

3 (6.7)

17 (14.4) TGEV

RV

6 (5.1) ETEC

RV

25 (21.2) Total single infections

2 (1.7)

C per.

4 (3.4) ETEC

11 (9.3) TGEV

3 (2.5) RV

3 (2.5) Crypto

2 (1.7) Cocci

Village (n=45) Commercial (n=117)

To determine the prevalence of the six major causes of

pre-weaning diarrhoea in commercial (CP) and village

pigs (VP) in Vietnam.

117 (from CP) and 45 (from VP) faecal specimens were

collected from cases of PrWD fro 6/2005 to 3/2008

All samples were tested for the presence of: 1) Cocci;

and 2) Crypto oocysts by standard faecal flotation and

modified Ziehl-Neelsen staining of faecal smears,

respectively; 3) RV; and 4) TGEV using an ELISA kit

(Institut Pourquier, France); 5) ETEC by aerobic culture

and PCR for enterotoxins and fimbriae; and 6) C

perfringens by anaerobic culture Results were

interpreted according to manufacturer’s

recommendations (ELISA kit) or as described [3].

Detection of multiple infectious agents from a single

specimen was common, with TGEV and RV being

endemic to all piggeries (Table 1)

In village pigs, agents were always found together with

one or more additional agents, while 25 cases from CP

were infected with only 1 causative agent.

ETEC occurred in older (>4 day-old) piglets; most

probably due to effective vaccination programs

These results and observations from farm audits

suggest that environmental conditions and husbandry

practices may be predisposing piglets to intestinal

infections.

1 Straw, B E., et al Diseases of Swine 1999: 41-59

2 Tzipori, S British Veterinary Journal 1988; 144: 521-523.

3 Diagnostic Manual of the Pig Health and Research Unit (Bendigo, Victoria, Australia).

ACKNOWLEDGMENTS

This work was supported by Ministry of Agriculture & Rural Development (Vietnam), National Institute of Veterinary Research (NIVR), Australian Government (AusAID) under Collaboration for Agriculture and Rural Development (CARD) Program

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2

Escherichia coli is one of the most important

enteric pathogens causing diarrhoea in pigs [1]

Pathogenic E coli often colonize the small intestine

by means of adhesion factors and produce one or

several disease-causing toxins [1]

Detection of virulence factors by molecular

techniques such as DNA hybridization and PCR has

been shown to be the most effective tool to

evaluate if an E coli isolated obtained from

diseased pigs is pathogenic and to provide suitable

measures of control and prevention [2]

1 Bertschinger HU, Fairbrother JM Escherichia coli infections

In: Straw BE, D'Allaire S, Mengeling WL, Taylor DJ, editors

Diseases of Swine Ames, Iowa: Iowa State University Press;

1999 p 431-468.

2 2 Wray C, Woodward MJ Laboratory diagnosis of Escherichia

coli infections In: Gyles CL, editor Escherichia coli in

Domestic Animals and Humans Wallingford, England: CAB International; 1994 p 595-628.

ACKNOWLEDGMENTS This work was supported by Ministry of Agriculture & Rural Development (Vietnam), National Institute of Veterinary Research (NIVR), Australian Government (AuAID) under Collaboration for Agriculture and Rural Development (CARD) Program

Virulence characterizations of Vietnamese strains of E

coli causing diarrhoea in pigs in Vietnam

Do NT 1 , Trott DJ 2 , Desautels C 3 , Fairbrother JM 3

1 Department of Bacteriology, National Institute of Veterinary Research, Hanoi, Vietnam

2 School of Veterinary Science, The University of Queensland, Brisbane, QLD 4072, Australia

3 The Escherichia coli Laboratory, Faculte de Medicine Veterinaire, Universite de Montreal, 3200 Sicotte, Saint-Hyacinthe, QC,

7 (17.1%)

14 (77.8%) EAST1

28 (68.3%) STx2

23 (56.1%)

12 (66.7%) LT

20 (48.8%)

16 (88.9%) STb

31 (75.6%)

14 (77.8%) STa

13 (31.7%)

2 (11.1%) AIDA-I

25 (61.0%)

13 (72.2%) Paa

30 (73.2%) F18

2 (11.1%) F5

6 (14.6%)

9 (50.0%) F4

PWD (n=41) PrWD (n=18)

Source of isolates (%) Virulence

factor

Table 2: The prevalence of different pathotypes

1 STa/STb

2 LT/Stx2

4 Paa/STa/STb/LT/EAST1

1 STb/EAST1

1 AIDA-I/STb/LT/EAST1

2 F4/Paa/STb/LT/EAST1

5 F4/Paa/STb/LT/EAST1

1 F4/STa/STb/EAST1

1 F4/STa/STb/Aero

2 F5/Paa/STa

1 AIDA-I/STb/EAST1

2 Paa/STa/LT/Stx2

13 F18/Paa/STa/LT/Stx2

3 F18/Paa/AIDA-I/STa/STb/Stx2

4 F18/AIDA-I/STa/STb/Stx2

1 F18/LT/Stx2

1 F18/AIDA-I/STb/Stx2

2 F18/Paa/AIDA-I/STa/Stx2

3 F18/AIDA-I/STa/STb

1 F18/STa/EAST1

2 F18/STa/STb

5 F4/ Paa/STa/STb/LT/EAST1

1 F4/STa/STb

PWD (n=41) PrWD (n=18)

Source of isolates Pathotype

To screen for the presence of 19 virulence factors

(F4, F5, F6, F17, F18, F41, EAE, P factor, Paa, AFA,

AIDA-I, STa, STb, LT EASTI, Stx1, Stx2, CNF, Aero)

in ETEC and ETEC/VTEC strains obtained from pig

with diarrhoea in Vietnam

E coli strains (n=18 from pre-weaning and n=41

from post-weaning piglets with diarrhoea) from

different provinces in Vietnam

ETEC or ETEC/VTEC were confirmed by primary

multiplex PCR (F4, F5, F6, F41, F18, STa, STb, LT,

VT2e)

DNA hybridization and PCR were further applied to

detect for the presence of 19 virulence factors

according to the protocol of The Escherichia coli

Laboratory, Faculte de Medicine Veterinaire,

Universite de Montreal

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3

The cost of pork production in Vietnam could be significantly reduced by the widespread use of locally made

efficacious vaccines to control endemic diseases such as neonatal colibacillosis

DEVELOPMENT AND EFFICACY TESTING OF A VACCINE

FOR THE CONTROL OF PRE-WEANING COLIBACILLOSIS

IN VIETNAM

Cu HP 1 , Fahy VA 2 , Driesen SJ 2 , Moore K 2 , Vanderfeen A 2 , Do NT 1 , and Trott DJ 3

1 National Institute of Veterinary Research, Hanoi, Vietnam

2 National E coli Reference Laboratory, Department of Natural Resources and Environment, Epsom, VIC 3554, Australia

3 School of Veterinary Science, The University of Queensland, Brisbane, QLD 4072

INTRODUCTION

1 VACCINE DEVELOPMENT

Table 2: Summary of ELISA results on pre- and

post-vaccination sera samples

ACKNOWLEDGMENTS

This work was supported by Ministry of Agriculture & Rural

Development (Vietnam), National Institute of Veterinary Research

(NIVR), Australian Government (AuAID) under Collaboration for

Agriculture and Rural Development (CARD) Program

5 0

80 3 2

4 0

Piglets born alive

Group 1 (8 sows) (Litterguard) Recorded criteria

Table 1: Recorded criteria on safety study

O64: F5/STa/STb/LT CARD-VN3

O149: K91:F4/STa/STb/LT CARD-VN2

O8:5F-/STa/STb/LT CARD-VN1

Virulence determinants Designation of strains

Table 1: E coli strains used for the preparation of vaccine

1 ml of inactivated whole cell vaccine contains 7.5 x 10 9 bacteria

Nạve sows each received 2 ml of vaccine

(approximately 1.5 x 10 10 bacteria) at 9 and 12 weeks

of gestation

No local or systemic reaction to the vaccine was

observed and all sows gave birth at the correct stage of

gestation to an average of 10 healthy piglets per sow

High antibody titers to F4 antigen were detected (as assessed by ELISA) for all three vaccines (p>0.1) compared to an unvaccinated control group (p<0.005).

There was no significant difference between the antibody response elicited (as demonstrated by OD values) by Litterguard, Ecovac or NIVR vaccines

a , b : p<0.005

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4

Some technical solutions suitable for development

of smallholder pig production in Quang Tri

province

Duyen T.T.B 1 , Coi N.Q 1 , C Cargill 2 , VA Fahy 3 , DJ Trott 4.

1 National Institute of Animal Husbandry, Hanoi, Vietnam; 3 South Australian Research Development Institute, 2 Victorian Department of Primary Industries; 4 School of Veterinary

Science, The University of Queensland, Australia.

Introduction

√ Quang Tri province is located on the coast of

Central in Vietnam, where always adversely affected

by extremely harsh climate Almost of the total pig

population in Quang Tri are raised in traditional

smallholder systems Therefore, suitable technical

solutions for development of pig production under

household condition are necessary and should bring

benefits for farmers This subject was funded by

CARD project 004/05VIE.

Materials and Methods

 The animals in the experiment were Mong Cai

sows (MC) and F1 crossbred (Mong Cai x Yorkshire)

The experiment was conducted at 30 households in

Hai Phu and Hai Thuong communes

 Implement technical solutions that were selected,

Evaluate performance and economical efficience of

pig production through applying technical solutions.

Results

Overall, with new technical solutions: Breeds,

feeding, using creep box for warming piglets and

training piglets to eat “Start feed” brought high

economical efficience

Objectives

√ To select suitable science technology in order

to develop pig production under household

condition in Quang Tri

Table 3: Testing of house selection for MC and F1 sows

Table 1: Reproductive physiology and performance of MC and F1 sows

1.22 34.86 1.3 37.28 Weaning period (days)

1.62 54.96 2.13 59.45 Weaning weight/litter

0.51 8.78 0.68 10.13 Weaning number/litter (head)

0.58 10.48 0.65 11.72 Number born alive/litter (head)

0.57 2.05 0.72 1.88 Litters/sow/year (litter)

4.52 334.00 6.59 304.7 Age of First farrowing (day)

mx X mx X

F1

MC Criteria

Table 2: Reproductive performance of MC and F1 sows in Feeding experiments

Within a row, values with different letters are significantly different (P<0.05)

Control group Experimental group

Traditional style Modern style

Control group Experimental group

Criteria

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5

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6

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Table 1: Results of diagnostic samples submitted to the lab (4/2005-10/2005)

Total No of samples tested Causative agents No of positive/Total %

Table 2: Results of diagnostic samples submitted to Bacto Lab (11/2005-6/2006)

Total No of samples tested Causative agents No of positive/Total %

Trang 22

Table 3 Common cause of scour in suckers

Agent Age of occurrence Sample Clinical Signs

NHEC 2hr-5 days Rectal swab or 2 gm of

faeces

Mild to severe scour, dehydration death Coccidia 5 – 15 days 2gm faeces Scour, death uncommon

HEC + 10 days through to

post weaning period

Rectal swab or 2 gm of faeces

Sudden death from endotoxemia shock or severe scour with dehydration

Table 2 Uncommon cause of scour in suckers

Agent Age of occurrence Sample Clinical Signs

Rotavirus, TGEV + 7 days into weaners 2 gm faeces Scouring, acidic faeces Clostridium

perfringens type A

1 – 21 days 2 gm faeces Non responsive scour,

affects growth rate

Clostridium

perfringens type C

2 + days 2 gm faeces, whole

animal, small intestine

Severe haemorrhagic enteritis

Salmonella 5 days of age to

weaning

Rectal swab, caecum terminal iliium, mesenteric lymph node, whole animal

Scour, ill thrift, emaciation, +/- pneumonia

Cryptosporidium 5 days of age to

weaning

2 gm faeces, whole animal, small intestine

Scour (blood), ill-thrift

Stronyloides

ransomi

10 days to post weaning

Faeces Severe diarhoea and

dehydration

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