DRINKING WATER VACCINATION IN CHICKEN

G.H. Hudson¹, K. Saravana Kumar¹, Simmi Tomar² and Surya Pratap Dhakare³  

¹PhD Scholar, ICAR- IVRI, Izatnagar

²Principal Scientist, ICAR- CARI, Izatnagar

³M.V.Sc Scholar, ICAR- IVRI, Izatnagar

Introduction

Vaccination is a commonly employed disease prevention technique in commercial chicken and backyard flocks. It allows the birds to build up immunity against a particular disease by mimicking the natural infection without any harmful effects. Vaccination in chicken can be done through different routes namely in-ovo injection, intramuscular injection, subcutaneous injection, ocular/nasal routes, feather follicle, wing stab method, spray vaccination and through drinking water.

Drinking water vaccination is a simple, quick and most practical method of mass vaccination technique in chicken. Vaccines for the diseases like New castle disease, Infectious bronchitis and Infectious bursal disease can be administered through drinking water.

Equipment

Drinking water vaccination should be carried out with dedicated equipments. The buckets and equipments used for disinfection / other medications should not be used as it may contain residual amount of disinfectants, antibiotics etc. which may inactivate the vaccine. Live vaccines are susceptible to ultraviolet light, heat, heavy metals, chlorine, organic matter, disinfectant, detergents, etc. Hence, these factors should be kept away from vaccines, equipments and water used for vaccination. Excessive bio-films in the drinker line should be removed by using the suitable products and the drinkers should be clean.

Calculation of water intake

Accurate vaccine dosing and dilutions are essential for successful drinking water vaccination. Early morning is the recommended period of drinking water vaccination, since birds will exhibit their maximum activity, such as first feeding period and therefore have peak water consumption.The amount of water consumed by a flock in two hours period is known, dilution can be made accurately. This can be done by monitoring the water intake of the birds during the same time period of the previous day before vaccination. Digital water meters can also be used to measure water consumption. Normally, vaccines are administered in drinking water for a period of two hours. If the vaccination time is less than 1 hour and 30 minutes, all the birds will not receive the proper dose of vaccine. If it is above two hours, the vaccine may get inactivated in the drinking water itself. General rule is that for every 1000 broilers a 1000 dose vaccine can be dissolved in the maximum of 40-45 liters of water. However, the amount of water required depends on the age group of birds, environmental temperature, strain of the birds etc. Sufficient drinker space should be provided so that, 2/3 of the birds in the flock should be able drink water at a time. Water can be withheld for a period of 1-2 hours before vaccination to stimulate thirst and thereby encourage water consumption. Some of the drinking water/ vaccinated water remains in the dead spaces of the drinker system and become unavailable for the birds. This should also be taken in consideration for calculating the quantity of water needed.

Calculation of amount of water in a Tank

Vaccine handling and dilution                            

The drinking water used for vaccination can be stabilized by the addition of skim milk powder. It should be added at a rate of 2.0 – 5.0 g per liter of water or 2.0 – 5.0 liters of skimmed milk per 100 liters of water. Addition of the skim milk powder will form flakes which may block the pipelines. This can be prevented by stirring the water, so that all the powder is dissolved.  The water should have optimum pH, but too high (>7,5) or too low (<6.0) pH will have negative effect on vaccine efficiency. Chlorine levels in drinking water as low as one ppm (1gram per 1000 lit of water) can even inactivate the vaccine.  Effervescent tablets available in markets can be used to neutralize chlorine if the levels are higher. The water should be at a temperature of around 15 degree Celsius which can be maintained by adding ice cubes. Certain commercial products like Vac-Safe , Blue farm contain chlorine neutralizer along with a water soluble blue dye. The dye when mixed with water changes the colour of water to blue, which can be used as an indicator of presence of vaccine water at the end of the drinker system. Further, these dyes mark the tongue, crop and feathers of the birds, in which the intensity of the color indicates the effectiveness of vaccination.

Vaccines should be purchased from the authorized supplier, ensuring that the cold chain is maintained properly. The expiry date, vaccine strain and number of doses required can be checked. It can be transported as per the manufacturer’s directions and kept at cold chain in the farm as soon as possible. Live vaccines are quite stable as long as they are in freeze dried form and stored in the refrigerator. On the day of vaccination, the vaccine vials should be prepared indoors and not in the floor of the entrance area of shed/ farm. Vaccine vials should be opened under water. Alternatively, vaccine diluents can be injected into the vial to dissolve the vaccine. When opening vaccine vials, hands must be clean (free of sanitizer/soap residues) or use disposable gloves. When reconstituting vaccines, it is better to use distilled water, or mains water that has been stabilized to neutralize chlorine.

Vaccine administration

1. The water supply should be turned off allowing the birds the drink the remaining water in the drinker line.
2. Raise the drinker line. Water deprivation should be done for about 60 minutes. Check the birds for the signs of excessive stress/ thirst
3. In the meantime, the unvaccinated water in the drinker line should be removed. The line should be flushed with untreated water to remove the residues of chlorine, antibiotics, etc.
4. The drinkers can be then primed with vaccine water. Check that the vaccinated water in the head tank has reached the end of the line
5. Lower the drinker line and allow the birds to consume the vaccinated water within 2 hours. Encourage the movement of birds to the drinkers, monitor stress and continued flow of vaccine.
6. After 2 hours, turn on main water line, clean the equipments, dispose of the remaining dose properly and continue to monitor the birds.

Monitoring and Record keeping

As already described the intensity of blue dye in the tounge can be used to monitor the drinking water vaccination. If vaccination has been done correctly, at least 90% of the tongues and crops will be colored blue. Further, the birds can also be checked for serum antibody levels. Proper records should be maintained with complete details of vaccination done.

Conclusion

Drinking water vaccination is one of the economical methods of immunizing the birds which incur lower labor cost, minimal stress to the birds and stimulates mucosal immunity. Inconsistencies of vaccine dosage and less number of birds covered can be effectively overcome by following standard vaccination protocols.