Vaccination

13 مايو 2020
Vaccination

Vaccination plays an important part in the health management of the poultry flock. There are numerous diseases that are prevented by vaccinating the birds against them
A vaccine helps to prevent a particular disease by triggering or boosting the bird’s immune system to produce antibodies that in turn fight the invading causal organisms

A natural invasion that actually causes the disease will have the same result as the bird will produce antibodies that fights the current invasion as well as to prevent future invasions by the same causal organisms Unfortunately, birds that become diseased usually become unthrifty, non productive or die. however vaccination provides a way of controlling the result with minimal harm to the birds

Types of vaccine

Live vaccine : the active part of the vaccine is the live organism that causes the disease. As such, it is capable of inducing the disease in birds that have not had previous contact that organism. Vaccinated birds, in many cases are able to infect non-vaccinated birds if housed together

Attenuated vaccine: with this type of vaccine the organism has been weakened by special procedures during manufacture so that it has lost its ability to cause the disease. At worst, the birds may contract a very mild form of the disease, however, the vaccine still has the ability to trigger the immune system to produce antibodies

Killed vaccine: with this type of vaccine the organism has been killed and is unable to cause the disease, although the ability to trigger the immune system remains. In many cases, the level of immunity produced by this form of vaccine is weaker than that produced by live and attenuated vaccines

Vaccine production

Vaccines are produced mainly in three forms

  1. Liquid vaccine
  2. Freeze dried vaccine : the vaccine is stored as one pack of freeze dried material and one pack of diluent, often a sterile saline solution. must be combined before use.
  3. Dust : where the vaccine is prepared for administration in the dry form
    Vaccines, the number of doses being the number of fowls that may be vaccinated with that amount of vaccine when using the recommended technique. In the case of many vaccines there are differences in the disease organism strains that they are effective against. It is important that the correct vaccine strain be used and this can only be determined by veterinary advice.

Handling vaccines on the farm

Vaccines are fragile in many respects and require very careful handling to ensure they retain their potency. Poor handling procedures will, in most cases, result in a rapid decline of potency

The important handling requirements on the farm are

On delivery of the vaccine on the farm, check and note

  1. That the vaccine has been transported in the suggested manner which is usually in the chilled or frozen state. long exposure to atmospheric temperature will result in rapid loss of power
  2. Must ensure the Type of vaccine you ordered
  3. Must ensure The number of doses been delivered
  4. The expiry date of the vaccine ,The expiry date is based on the vaccine being handled and stored in the recommended manner
  • As soon as possible place the vaccine into recommended storage conditions. Read the instructions to find out what these are. However, freeze dried material should be kept at a temperature below freezing and its diluent at a temperature just above freezing. Liquid vaccines are generally kept at temperatures just above freezing
  • Remove the vaccines from storage immediately prior to their being used. Do NOT mix what is required for an entire day at the start of the day and leave it stand until required, as the vaccine will rapidly lose it efficacy
  • Protect the vaccines after mixing by holding them in an ice bath. Place ice in a small similar container and place the container of mixed vaccine in the ice. Some vaccines have a very short life once mixed
  • Use the recommended administration techniques and do not vary these without veterinary advice
  • Always clean and sterilize the vaccinating equipment thoroughly after use
  • Always destroy unused mixed vaccines after the task has been completed. Some vaccines have the potential to cause harm if not destroyed properly
  • Do not vaccinate birds that are showing signs of disease or stress