Winter is a high-incidence period for diseases on chicken farms — which chicken diseases are more suitable for emergency vaccination?

Entering winter, temperatures drop sharply, and diseases on chicken farms enter a high-incidence period, making vaccination of chickens especially important, particularly emergency vaccination after an outbreak in the flock. For some chronic, atypical infectious diseases, a few chickens fall ill first; if not handled properly, the disease will sweep through the entire chicken farm, bringing incalculable losses to the farmer. If the chicken farm detects it in time and carries out emergency vaccination of the flock with a vaccine (bacterial vaccine), activating their immune system so that they develop immunity, susceptible chickens become non-susceptible chickens, the progression of the disease slows down, and the disease will be stamped out.

As a chicken farm manager, you must be clear about which chicken diseases emergency vaccination is suitable for.

Fowl Pox

If a few chickens in the flock are found to have “pox”, immediately carry out emergency vaccination of the whole flock, and at the same time kill mosquitoes in the chicken house for 3-4d consecutively; after a few days no new sick chickens will appear in the flock. For flocks detected later with severe disease, even if a few chickens have swollen-shut eyes, emergency vaccination still has a fairly good effect. But two points should be noted: first, isolate or cull the few severely affected sick birds; second, kill mosquitoes and other blood-sucking insects in the chicken house environment, and install screens on the chicken house; the disease can be controlled in about 1 week.

Newcastle Disease

Clinically it mostly appears with atypical symptoms, generally without nervous symptoms, only a decrease in egg production and reduced feed intake, sporadic deaths, and some have respiratory or digestive tract symptoms. The effect of emergency vaccination is obvious, with improvement after a few days; for a few severely affected flocks, simultaneously injecting 1 dose of oil vaccine gives an even better effect.

Fowl Cholera

Fowl cholera is caused by Pasteurella multocida, also called avian hemorrhagic septicemia, characterized by diarrhea and sudden death. Emergency vaccination of the flock in the early stage of the disease has a certain preventive effect; at the same time, disinfect the water troughs, feed troughs and environment to kill bacteria in the environment, which can quickly control the disease. For flocks with many deaths, emergency vaccination combined with antibiotics gives a better effect.

Infectious Laryngotracheitis

When the first chicken is found sick or dead, carry out emergency vaccination of all flocks on the farm, using laryngotracheitis vaccine by eye drop and nasal drop; after a few days deaths stop, symptoms disappear, and the whole flock recovers.

Infectious Coryza

This disease is caused by Haemophilus gallinarum, characterized by inflammation of the nasal cavity and sinus cavities and swelling of the face (commonly called swollen head), with no deaths or very few deaths, and it has a relatively large impact on egg production. When this disease occurs, the flock cannot reach peak egg production or egg production during the peak period declines; treatment with sulfonamide drugs gives relatively ideal results, but relapse occurs very easily.

Usually some chickens fall ill first, and after treatment and recovery, another group of chickens falls ill again, repeating over and over. Generally the number of outbreaks in a flock is 2-4 times, and a few flocks reach more than 5 times. When infectious coryza occurs, if an inactivated vaccine is used for emergency vaccination of the flock, together with a small amount of medication and separate treatment of individual sick chickens, the disease can be quickly controlled. If many chickens are affected, medication can also be given to the whole flock.

Several issues to note during emergency vaccination

1. The virulence of the vaccine used for emergency vaccination must be appropriate. If the virulence is too high, it will aggravate the disease after vaccination and the flock mortality rate will rise; if the virulence is too low, the immune effect is poor. The disease cannot be controlled.

2. The dose must be appropriate. Too large a dose causes a strong reaction in chickens and increases deaths; too small a dose means a small amount of antigen enters the chicken body, and the vaccination effect is not ideal. Therefore, the virulence of the vaccine for emergency vaccination must be appropriate, and the dose must be large enough without causing serious reactions in the chickens.