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Possible application methods and compatibility of Nobilis CAV P4

Introduction

Avian Infectious Anaemia is a viral disease present in all major chicken producing countries of the world. All ages are susceptible to infection but susceptibility to disease decreases during the first 2-3 weeks of life. The virus spreads both vertically and horizontally in chickens. Vertical transmission occurs following primary infection of in-lay breeding stock and results in clinical disease in their progeny towards the end of the second week of live. Horizontal spread occurs through contact with vertically infected chicks, contaminated houses, materials, etc. and usually results in subclinical infection. The physical resistance of the virus to inactivation is relevant in this context. Both clinical and subclinical infection cause economic losses, therefore the need for vaccination.

Control of the disease

The immunization of breeding stock before the onset of lay will efficiently prevent outbreaks of infectious anaemia in their progeny. Furthermore, if high uniform antibody levels can be induced in breeding stock, the resulting high levels of maternally derived antibodies (MDA) may prevent or at least delay horizontal infection in the progeny and thus prevent or decrease economic losses due to subclinical infection.

Author: Aris Malo 1Date: December 2006


Nobilis CAV P4

Nobilis CAV P4 is a live vaccine for the vaccination of breeding stock, based on an attenuated virus strain. The attenuated vaccine virus possesses a significantly reduced pathogenicity but has retained its immunogenic properties. Before onset of lay high levels of humoral neutralizing antibodies are induced which prevent vertical transmission of the virus to the progeny. These high levels are maintained for at least one laying period and make revaccination during lay unnecessary. In the progeny, the high levels of MDA delay the time before the progeny becomes susceptible to horizontal infection.

Compatibility and application methods

Since vaccination programs - especially in breeding stock - are generally congested it is preferable and desirable to simplify the application of several antigens / vaccines by combining them in one presentation or when possible by applying them simultaneously. An important aspect in this respect is the compatibility (absence of interference) of the different antigens. Extensive laboratory and field experiments have shown that Nobilis CAV P4 is compatible for administration in combination with several other vaccines, offering a wide range of choices to the end user.

Vaccination with Nobilis CAV P4 should be administered by intramuscular or subcutaneous injection or by the wing web method. When administered via the wing web method special attention should be given to the application technique. A bad application technique when using the wing web method may result not only in a poor “take” of the Pox component in the vaccine but also in a poor “take” of Nobilis CAV P4. This can be illustrated in the following example:

Breeder flock vaccinated with Nobilis CAV P4 via the wing web method in combination with Nobilis Ovo-Diphterin:

House Nr. of samples CAV Log2 antibody titer Percentage 4 weeks post vaccination negative birds

1 10 4.6 17%2 10 11.6 7%

The poor titers observed in house 1 against CAV after vaccination via the wing web method in combination with Nobilis Ovo-Diphterin resulted from a poor application technique; this correlated with a poor “take” of the pox vaccination.


Possible application methods and compatibility of Nobilis CAV P4 Vaccination via the drinking water or spray is not recommended since these methods do not result in a rapid and solid immunity. Using the recommended administration methods Nobilis CAV P4 induces high neutralizing antibody titers within 3-4 weeks post vaccination. Nobilis CAV P4 can be administered as a single product or in combination with the following products:

Nobilis Reo 1133 (s.c./i.m.) Nobilis AE Pox (w.w.) Nobilis Ovo-Diphterin (w.w.) Inactivated vaccines containing IB, ND, IBD, APV, Reo and/or EDS

antigens (s.c./i.m.)

The use of Nobilis CAV P4 in combination with inactivated vaccines

In this paper we will concentrate on the efficacy of the simultaneous application of Nobilis CAV P4 in combination with inactivated vaccines, as this offers a wider variety of possibilities for vaccination.



Experiment 1

In the first experiment Nobilis CAV P4 was administered in combination with “Breedervac-IV-Plus”, an inactivated vaccine from Intervet Inc (USA) for breeders against Infectious Bronchitis, Newcastle Disease, Reovirus and Infectious Bursal Disease.

Design:

A group of 15 SPF chickens vaccinated i.m. with Nobilis CAV P4 in combination with Breedervac - IV – Plus at 3 weeks of age

Blood samples collected at the moment of vaccination and 31/2

weeks later Sera tested in a competitive ELISA

Table 1: CAV serology before and after vaccination

Bird nr. Log2 ELISA titer at….weeks post vaccination0 31/2

1 negative 92 negative 93 negative 94 negative 105 negative 106 negative 107 negative 108 negative 109 negative 1010 negative 1011 negative 1012 negative >1113 negative >1114 negative >1115 negative >11

Results:

Three and a half weeks post vaccination all birds had responded with high and uniform levels of antibodies against Avian Infectious Anaemia.

Experiment 2

In the second experiment Nobilis CAV P4 was administered in combination with Nobilis Reo IB G ND, an inactivated vaccine for breeders against Reovirus, Infectious Bronchitis, Infectious Bursal Disease and Newcastle Disease.Author: Aris Malo 4Date: December 2006


Design:

Two groups of 12 SPF chickens each, one group vaccinated s.c. with Nobilis CAV P4 in combination with Nobilis Reo IB G ND at 3 weeks of age; the other group received only the inactivated vaccine Nobilis Reo IB G ND without the addition of Nobilis CAV P4.

Blood samples collected at 3 and 6 weeks post vaccination Sera tested accordingly as follows:

- CAV: Competitive ELISA- Reovirus: ELISA- Infectious Bronchitis: HI test- Newcastle Disease: HI test- Gumboro: VN test

Table 2: Log2 antibody titer against …at…weeks post inoculation

Group

Treatment CAV ND IB REO IBD

3w 6w 3w 6w 3w 6w 3w 6w 3w 6w1 CAV P4 +

Inactivated Vaccine

10.8

11.3

7.7

8.2

4.8

8.6

10.6 12.7 15.8 15.3

2 Inactivated Vaccine

3.0 3.0 6.8

6.7

3.3

4.7

9.2 10.7 13.3 14.9

Results:

The addition of CAV P4 to the inactivated vaccine did not negatively influence antibody development for any of the antigens included in the combination. Indeed the titers for the inactivated components showed higher levels when compared to the group that did not receive the inactivated vaccine in combination with Nobilis CAV P4.

Experiment 3

In the third experiment Nobilis CAV P4 was administered in combination with an inactivated vaccine against Reovirus, Infectious Bursal Disease, Newcastle Disease, EDS and Avian Pneumovirus.



Design:

Four groups of 12 - 4 weeks old - SPF chickens each, one group vaccinated i.m. with Nobilis CAV P4 in combination with the inactivated vaccine; the other group received only the inactivated vaccine; another group received only Nobilis CAV P4 and another group was left unvaccinated as control.

Blood samples collected at 4 and 6 weeks post vaccination Sera tested accordingly as follows:

- CAV: VN test- Reovirus: VN test- Avian Pneumovirus: ELISA- Newcastle Disease: HI test- EDS: HI test- Gumboro: VN test


Possible application methods and compatibility of Nobilis CAV P4Table 3: Log2 antibody titer against …at…weeks post inoculation

Group

Treatment CAV Reo G ND APV EDS

4w 6w 4w 6w 4w 6w 4w 6w 4w 6w 4w 6w1 CAV P4 +

Inactivated Vaccine

11.3

12.3

6.8

7.9

19.5

18.5

8.0

8.1 11.0 10.3 9.8

9.1

2 Inactivated Vaccine

3.0 3.0 5.4

7.8

18.8

16.9

7.3

7.3 10.2 8.9 9.0

8.6

3 CAV P4 9.3 11.0

- - - - - - - - - -

4 None - - - - - - - - - - - -

Results:

Once again, the addition of CAV P4 to the inactivated vaccine did not negatively influence antibody development for any of the antigens included in the combination. In addition, the titers for the inactivated components showed a higher level when compared to the group that did not receive the inactivated vaccine in combination with Nobilis CAV P4.

Conclusion:

From the results obtained it can be concluded that the live vaccine Nobilis CAV P4 can be added to inactivated vaccines containing the antigens included in the experiments shown above. High antibody levels were obtained not only against the avian Infectious Anaemia virus but also against the components included in the inactivated vaccines used. The birds vaccinated with the combination did not show at any moment signs of distress.

Vaccination:

Nobilis CAV P4 should be applied to breeding stock from an age of 6 weeks onwards and at least 4 weeks before the onset of the production period. In order to achieve high levels of antibodies the vaccine should be applied by the intramuscular, subcutaneous or wing web methods, all giving comparable results. The high and consistent level of antibody titers achieved is maintained for at least one laying period. Results obtained in compatibility experiments demonstrate that it is possible to use Nobilis CAV P4 in combination with Nobilis Reo 1133 (s.c./i.m.), Nobilis AE Pox (w.w.), Nobilis Ovo-Diphterin (w.w.) and inactivated vaccines containing IB, ND, IBD, APV, Reo and/or EDS (s.c./i.m.). This provides possibilities


Possible application methods and compatibility of Nobilis CAV P4for convenient combined vaccination programs.



The following items need further discussion:

1) To combine Nobilis CAV P4 with an oil emulsion vaccine first dissolve the live vaccine in 1-2 ml of sterile distilled water or PBS (phosphate buffered saline). Subsequently the dissolved vaccine is added aseptically to the inactivated vaccine. Thereafter, the inactivated vaccine should be gently shaken in order to ensure a thorough mixture of the components. Do not use the diluent “Dilavia” for this purpose.

2) The combination is safe and efficacious, however it is not yet officially licensed.

3) The mixed vaccines should be used within 2 hours after preparation.

4) When vaccinating via the wing web method, the application process should be carefully monitored in order to avoid poor vaccine “takes”.

=================================================5) Dear Dr.Khalid Shouq6)7) the incidence of chicken Anemia disease is increasing day by bay in

commercial layer. its a viral disease and control by the use of vaccination in breeder only. some commercial farmers are interested to use vaccine in commercial layer but not recommended in commercial birds. always use chicken Anemia vaccine in breeder at least 6-8 weeks before laying.

8)9) please find attached CAA article received from intervet for our

technical persons.10)11) With Best Regards,12)

13) 14) Dr. Muhammad Umar

Director Sales & Marketing15) Vety Care (Pvt.) Ltd.

Plot # 81-A Street No. 06, I-10/3, IslamabadTel : +92 51 111 103 103 Cell : +92 307 7772049

16)


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