Warming Oil Emulsion Bacterin Prior to Injection

Extracted from a presentation “Evaluation of the effect ofheating an oil emulsion Pasteurella multocida bacterin on tissuereaction and immunity.”Karen E. Burns, Jaime Ruiz, and John R. Glisson. Poultry Diagnostic and ResearchCenter, University of Georgia. Presented at AAAP, 2001 Boston.

Introduction

Oil emulsion inactivated vaccines arecritical components of vaccinationprograms for long lived birds, i.e.breeders, layers and turkeys.

These vaccines provide a long durationof immunity and improve antibodyresponse for breeders in order toprovide protective maternal antibodiesto progeny.

Cont. …

Common injection sites include:

1. Subcutaneously (S.Q.) in the back of the neck, ventral side ofthe tail.

2. Intramuscularly (I.M.) in the breast, thigh or leg muscles.

Cont. …

There are some inherent problems in all vaccination techniquesroutes;

1. S.Q. neck injection offers the highest risk for accidentalhuman injection.

2. Deeper injection into the muscles of the neck results in pain,feed refusal and cull birds.– Oil emulsion bacterins tend to be the most reactive when injected

into the muscle.

3. Tissue reaction can result in a greater incidence ofcondemnations at processing.

Lesion in neck muscle of breeder pulletfollowing improper injection technique ofan oil emulsion vaccine

Study Aim

In order to examine a field solution to the problem of I.M.injection reaction, a simple investigation was completed at theUniversity of Georgia to determine if heating the vaccine wouldreduce the reaction in the breast muscle.

Cont. …

Personal communication from an industry vaccination crewindicated that they were heating an oil emulsion bacterin in awater bath prior to I.M. injection into the breast.

It is known that heating an oil emulsion decreases theviscosity of the vaccine.

In theory, by adjusting the vaccine closer to the birds’ bodytemperature, the vaccine may be less likely to leave a lesionat processing, possibly because of more rapid absorption ofthe vaccine.

Comparing the heated vaccine to room temperature vaccineallowed evaluation of a commonly used field technique andlabel recommendation.

Materials and Methods

Vaccines:

The study used a commercially prepared P. multocida bacterincontaining serotypes 1, 3, and 4 from the same serial and lot,refrigerated until use.

Vaccines were allocated into 2 groups;

Cont. …

1. The heat treatment vaccine was performed by placing thebottle in a microbiological incubator set to 41 C (105° F) forfive hours before vaccination.

The vaccine was placed in a foam-insulated container fortransport to pens for immediate injection.

2. The room temperature vaccine was placed out ofrefrigeration for 12 hours and allowed to warm to roomtemperature.

Study Design

Group No. of birds 10 weeks 18 weeks 24 weeks

Heated Vaccine 50 • Vaccination• Right Serology

• Vaccination• Left Serology

• Challenge & Serology (25 birds)

• Lesion Score (25 birds)

Room Temp Vaccine

50 • Vaccination • Right Serology

• Vaccination• Left Serology

Controls 50 • Serology Only • Serology Only

Right and Left indicate side of the breast muscle where injection occurred. Groups were divided at 24 weeks, 1/2 challenge and 1/2 lesion scored.

Cont. …

Birds were injected intramuscularly in the superficial pectoralmuscle with 0.5 mL of the bacterin using an 18-gauge 1/4 inchneedle.

Challenge

25 birds from each treatment group were challenged at 24weeks of age with 1.0 mL serotype 1 P. multocida (X-73 challengestrain, 2.0 X 10 log 2 colony forming unit/mL) by I.M. injection inthe left thigh.

Evaluation

Antibody titer

Antibodies to P. multocida were measured using the IDEXX ELISAfor P. multocida.

Cont. …

Lesion Scoring

25 birds from each treatment group were euthanized at 24weeks of age.

Both breast muscles were carefully incised to reveal thesuperficial and deep pectoral muscles.

The following scoring system was used to subjectivelyevaluate the injection lesions:

0 = no visible lesions

1 = small focal lesion within one muscle layer, < 1cm in diameter

2 = small multifocal lesions of < 1cm in diameter, same muscle layer;

3 = large focal or multifocal lesions > 1cm in diameter, including lesions that extended into deeper muscle layer

4 = abscessation, deep pectoral myopathy, lesions that were diffuse, > 5cm in diameter

Results

Treatment groupTiter10 weeks

CV%Titer18 weeks

CV%Titer24 weeks

CV%

Heated 5 181% 1635 66% 3136 56%

Room temp 16 112% 946 73% 2841 82%

Control 38 74% 15 137% 7 121%

Titers for P. multocida tend to be highly variable and will have higher CV%than typically seen with viral titers.

Cont. …

Titers for P. multocida tend to be highly variable and will havehigher CV% than typically seen with viral titers.

Lesion Score 6 weeks post vaccination

Score 0 Score 1 Score 2 Score 3 Score 4

0%3%

31%

38%

10%

1% 0%

10%

36%

24%

48%

0% 0% 0% 0%

% of birds

Heated Room Temperatre Control

Lesion Score 14 weeks post vaccination

Score 0 Score 1 Score 2 Score 3 Score 4

6%

49%

26%

0% 0%0%

21%

45%

2%0%

47%

1% 0% 0% 0%

% of birds

Heated Room Temperatre Control

Mortality

Mortality

0%

11%

71%

% of birds

Heated Room Temperatre Control