Diary of a Poultry Farmer: Steps in administering fowl pox vaccine

Two weeks ago, I narrated the dos and don’ts when administering vaccines in water.

One of the things I talked about was ensuring that chemicals such as chlorine found in water, disinfectants, detergents and metallic ions from heavy metals do not get into contact with the live vaccine.

I also cautioned that a good vaccination programme is not a substitute for good farm hygiene practices (Seeds of Gold, November 26, 2016).

I further shared the vaccination programme for improved indigenous birds, which you need to refer to. As usual, my farm manager has been on top of things this past weeks and after we had administered the first Newcastle vaccine and second Gumboro at day 21 and 24 respectively, it was time to give the fowl pox vaccine at week six.

Fowl pox is a slow-spreading disease of fowls and turkeys caused by avian pox virus. There is no known treatment and vaccination offers the best protection.

There are two types, that is, the dry pox and the wet pox. The latter is more serious and it can cause a high mortality of between 50 and 60 per cent in unvaccinated chickens.

Dry pox results in scabs and lesions around the comb, wattle, ear lobes and eyes. Although dry pox doesn’t cause significant deaths in the flock, it can drastically reduce egg production by about 15 per cent.

On this particular day, Cleophas had called to inform me about his plans to administer the fowl pox vaccine.

“In addition to the vaccine, I need a two-pronged wing-web needle applicator,” he said. “I will also need an assistant.” Suddenly, his phone went off. Luckily, it was my day off and I quickly dashed to the farm.

You see, fowl pox vaccine is given as a needle stab in the wing, the so-called ‘wing web stab’. The procedure requires to be undertaken by a skilled worker. I had asked Cleophas to seek the help of the vet technician at the agrovet in Njiru.

Because she was busy, he instead carried a chick to the shop so that she could demonstrate the procedure.

The ‘wing web stab’ is a route used when you are vaccinating chicken against serious diseases like fowl pox.

The first thing was to mix the vaccine with the diluent that comes with it.

CHECK VACCINATION SUCCESS AFTER SEVEN TO TEN DAYS

The vet then gently lifted the left wing of the chicken to ensure the underside was facing up. “This exposes the wing web,” she explained. She then gently plucked some of the feathers on the wing web so that we could see the area.

“None of the vaccine should get on the feathers,” she cautioned.

I learnt that the wing web is located near the bone where the wing connects to the body. Cleophas then held the chick as instructed.

The vet then dipped the two-pronged needle applicator into the vaccine bottle, taking care to ensure that the needle was not dipped too deeply. “Only the wells of the two pronged needles must be dipped into the vaccine,” she said.

Finally, she pierced the underside of the wing web, avoiding the blood vessels and bones. “You avoid the vessels by centering the needle puncture in the middle of the triangle formed by the wing web, while the wings are spread apart.”

She told us that in case you accidentally hit a vein and bleeding occurs, replace the needle with a new one, and re-vaccinate.

Another thing was that the needle should be replaced with a new one after vaccinating 500 chickens. Check whether the vaccination was successful after seven to 10 days. “Pick 50 birds randomly and check them for scabs (swelling) under the wing web,” she explained.

“Scabbing or scarring means that the vaccination was successful”.

For sure, vaccination should be done prior to expected exposure to the fowl pox virus. One vet told me some time back that areas with mosquitoes throughout the year should administer two vaccinations, one early and one later for “permanent” protection.

If you check the Indigenous Chicken Vaccination Programme from Kenya Agricultural and Livestock Research Organisation, it prescribes two options: At six weeks, or in hot spot areas, much earlier, at three weeks.

A week later, Cleophas texted six-day post vaccination results. “47 birds out of 50 had the scar.”

This means the ‘take’ was about 94 per cent although experts note it must be much higher, at least 99 per cent of vaccinated pullets should show the scar.