Target Species
Chickens.
Indications for use
For the active immunisation of chickens to reduce mortality, clinical signs and lesions after infection with Marek’s disease virus.
Contraindications
None.
Special warnings for each target species
None.
Special precautions for use
The presence of maternal antibodies to Marek’s can affect the efficacy of the vaccine.
The vaccine viruses spread; care should be taken to prevent such spread in multi-age sites.
A good immune response is reliant on the reaction of an immunogenic agent and a fully competent immune system. Immunogenicity of the vaccine antigen will be reduced by poor storage or inappropriate administration. Immunocompetence of the animal may be compromised by a variety of factors including poor health, nutritional status, genetic factors, concurrent drug therapy and stress.
Operator warnings
The operator should be aware of the general precautions to be taken when handling liquid nitrogen and/or material at very low temperature. Ampoules may explode on sudden temperature changes; therefore the operator should protect himself with thermal gloves and a visor. When removing an ampoule from a cane hold the palm of a gloved hand away from body and face. After handling vaccine operators should wash and disinfect hands with an approved disinfectant.
First aid treatment of frost bite injuries: Warm affected part by immersion in water at 29 ± 1ºC or use body heat. There will be considerable pain during warming, but this is normal. Do not rub affected area, seek medical advice.
Adverse Reactions
None.
Use during pregnancy or lactation
Not to be used for birds in lay.
Interactions
No information is available on the safety and efficacy of this vaccine when used with any other veterinary medicinal product. A decision to use this vaccine before or after any other veterinary medicinal product therefore needs to be made on a case by case basis.
There is evidence that some antibiotics may interfere with the performance of Marek’s vaccines if mixed for administration.
Amounts to be administered and administration route
Day-old vaccination:
Inject 0.2 ml reconstituted vaccine to each bird subcutaneously in the neck or intramuscularly in the leg using a 20g x 1/2" needle with an approved repeating syringe or automatic vaccinator.
In-ovo vaccination:
Inject one dose of the reconstituted vaccine to each 18-day embryonated egg with an appropriate automatic in ovo vaccinator. The actual volume per dose may depend on the settings of the in ovo vaccination equipment. This should not be less than 50µl or more than 100µl. Depending on the volume to be administered the vaccine should be reconstituted according to the instructions below. The egg should be in an upright position with the blunt side up.
Reconstitution:
The actual volume of solvent per dose needed for reconstitution of the vaccine may depend on the number of doses per ampoule, the route of administration and for in ovo on the settings of the vaccination equipment. In the table below the volume of solvent per ampoule for the various dose-presentations, routes of administration and settings of the in ovo equipment are given.
| Volume of solvent per ampoule needed for reconstitution of the vaccine |
Number of doses per ampoule | sc/im (0.2 ml per dose) | in-ovo (0.1 ml per dose) | in-ovo (0.1 ml per dose) |
1000 doses | 200 ml | 50 ml | 100 ml |
2000 doses | 400 ml | 100 ml | 200 ml |
4000 doses | 800 ml | 200 ml | 400 ml |
5000 doses | 1000 ml | 250 ml | 500 ml |
Prior to reconstitution the vaccine is thawed. Great care should be taken - see operator warnings. Remove one ampoule from the cane and immediately replace the cane in the liquid nitrogen canister. Thaw the contents of the ampoule rapidly by immersing in water at room temperature. Do not thaw in hot or ice-cold water. Dry the ampoule and shake to disperse contents. After thawing open the ampoule immediately and draw the entire contents into a sterile 5 - 10 ml syringe using an 18 gauge needle to avoid rupturing the cells. Insert the needle through the stopper of the solvent vial (which should be at room temperature) and draw up slowly a portion of the solvent. Add the contents of the syringe to the remaining solvent. It is important that this is done slowly, allowing the vaccine to run down the side of the bottle. Gently shake the bottle as the vaccine is being mixed. Withdraw a portion of the vaccine and use to rinse the ampoule. Inject the washing back in to the solvent vial. The reconstituted vaccine must be handled gently and administered through wide gauge needles to avoid rupturing the cells. Fill the sterilised repeating syringe/automatic vaccinator according to the manufacturer’s instructions. The vial of reconstituted vaccine should be kept in an ice bath when not being used.
Overdose
No adverse effects anticipated. Occasional microscopic lesions might be seen after in ovo vaccination. No specific treatment or antidote recommended.
Withdrawal period
Zero days.