CASE 1

A Case of Hepatotoxicity in Broilers

 

SUMMARY

 

A sudden rise in morbidity and mortality was seen in a single house of 35 day old broilers within an integrated company. Post mortem and histopathological examination revealed an hepatotoxic insult. Investigations did not conclusively identify the causal agent.

 

THE COMPLAINT

 

The initial complaint was an increase in mortality from 29 days old in house 6 on an eight house broiler site. This was reported verbally. Considering the previous site and current company disease history of necrotic enteritis, a 3 day course of 16 mg/kg water soluble amoxycillin (Amoxypen SP;Intervet) was prescribed.

 

SITE HISTORY

 

Placement Details

 

The birds were placed on 16-17/8/99.

 

  H.1 H.2 H.3 H.4 H.5 H.6 H.7 H.8
Bird Numbers 27500 28447 28000 28500 27500 28500 28395 30000
Parent

Flock

Codes

32,14 10,14,28

48

33,48 20,28

40

20,32 10,15 10,20,23

33,46

20

 

 

Production

 

H.6 Production

Age (days)

Weight (kg)

Cumulative Mortality (%)

7

0.175

1.01

14

0.406

1.53

21

0.791

1.97

28

1.219

2.34

35

ND

6.62

ND=Not done

 

 

 

Mortality

 

 

Last 7 days Total Mortality

 

T (35d)

T-1(34d)

T-2

T-3

T-4

T-5

T-6

H.6

259

229

157

81

63

35

21

 

 

Site Production

 

 

Age (days)

Bodyweights (kg)

 

H.1

H.2

H.3

H.4

H.5

H.7

H.8

Target

7

0.153

0.135

0.153

0.145

0.135

0.154

0.123

0.150

14

0.390

0.375

0.395

0.352

0.380

0.383

0.360

0.400

21

0.760

0.740

0.730

0.735

0.707

0.752

0.660

0.800

28

1.198

1.136

1.147

1.150

1.074

1.123

1.096

1.200

35

ND

ND

ND

ND

ND

ND

ND

 

 

 

 

Age (days)

Mortality (%)

 

H.1

H.2

H.3

H.4

H.5

H.7

H.8

7

0.90

1.37

0.98

0.81

0.77

2.50

1.30

14

1.36

1.76

1.32

1.08

0.99

3.25

1.71

21

1.81

2.25

1.71

1.44

1.32

3.54

2.26

28

2.10

2.48

1.97

1.75

1.67

4.16

2.63

35

2.58

2.82

2.28

2.08

1.95

4.52

2.95

 

 

 

 

 

 

 

 

INVESTIGATIONS

 

Post Mortem Examinations

 

Post Mortem Ref: P1059

Examined 20.9.99

 

Pm Ref. Age (days) Weight (kg) PM lesions Bacteriology Swab
P1059

H.6

12 dead

35 1.28-1.57 Congested lungs

Fatty, pale livers

Nasal exudate

Mucopus in the trachea

Tracheitis and splenomegaly

Catarrhal enteritis

Large numbers of weed seeds in gizzards

E.coli

 

Liver

Air sac

 

Comments and Recommendations:

 

Mortality had continued to rise, despite antimicrobial medication. There was no evidence of Gumboro disease or necrotic enteritis in the submitted birds.

 

There was no report of respiratory symptoms in the birds on site, and it was apparently not possible to identify sick birds. The significance of the weed seeds in the gizzards was not known. These can be seen in small numbers in broilers fed on whole wheat diets, but not to the extensive quantity seen in some of these birds. Due to the increasing nature of mortality on the farm, and the inconclusive post mortem findings live birds were requested for further post mortem examinations to clarify the picture.

 

Post Mortem Ref: P1062

Examined 21.9.99

 

P