Diary of a Poultry Farmer: Two diseases that will give you trouble

A poultry farmer in Embu checks on one of his birds. Birds' response to treatment should be monitored closely by your regular vet and if treatment fails to work, their housing units should be cleared of all the birds for three months to disinfect it. FILE PHOTO | NATION MEDIA GROUP

What you need to know:

  • If you recall, two weeks ago, I recounted my ordeal in the hands of a stubborn chicken disease that had claimed 136 out of 320 chicks.
  • After consulting several experts and getting conflicting advice, I decided to seek a fourth opinion from Dr Mugachia of Gardenvet in Nairobi, who contacted me after reading my article.
  • In addition to carrying out a thorough clinical investigation of the diseases and poultry production systems, he conducted a post-mortem on one bird that had died.
  • Coming from a medical background where the problem of antibiotic resistance is rampant, I found this advice invaluable.

“The report is ready,” Dr Mugachia said when I picked his phone call last week.

“I am in a meeting, can we talk later?” I replied, though I was anxious to know what he had come up with after assessing my chickens that were dying one by one.

If you recall, two weeks ago, I recounted my ordeal in the hands of a stubborn chicken disease that had claimed 136 out of 320 chicks.

After consulting several experts and getting conflicting advice, I decided to seek a fourth opinion from Dr Mugachia of Gardenvet in Nairobi, who contacted me after reading my article.

He wrote, “The high death rate in your flock may indicate the presence of another infection other than fowl pox. A proper diagnosis requires a farm visit by a veterinary surgeon near you.”

The problem was that my regular vet, Dr Omari, had travelled upcountry and by the time Dr Mugachia visited my farm in Njiru, the death toll had reached 176 (55 per cent of the flock).

In addition to carrying out a thorough clinical investigation of the diseases and poultry production systems, he conducted a post-mortem on one bird that had died. So that morning, he had called to share his findings.

For sure, based on readers’ emails, I was not the only farmer dealing with this problem. Anne Kadenyi wrote to say that all her birds had died showing the same signs although she was told the problem was spread by mosquitos.

“The birds developed small black spots on the neck and eye lids. The eyes then became swollen and eyelids closed as a creamy pus developed inside. How do I get rid of the mosquitos?” she inquired.

Of course experts agree on one thing. Since the blindness from infectious coryza prevents feeding, the birds die from starvation.

TRANSMITTING THE INFECTION TO OTHER BIRDS

After my meeting, I called Dr Mugachia. “There is some good news and bad news, which do I start with?” he teased. Being an optimist, I preferred the good news first.

“The good news is that you have a good vaccination programme in place and fowl pox infection in your flock seems insignificant for now,” he said. I was eager to hear the bad news.

“The bad news is that your birds seem to have a mixed infection of infectious coryza and mycoplasma that may be responsible for the head swellings and high death rates. You need to improve your housing structures, bio-security (basic hygiene) and the size of your operation to make the venture economically viable,” he offered.

By now, I was feeling dizzy and took a seat. From my recollections, the last time infectious coryza was diagnosed in my flock, I was advised to use antibiotics called Tylosin and Forceback.

To the contrary, the good veterinary surgeon with over 28 years of experience in the various aspects of animal health service and development replied curtly, “Tylosin does not eradicate the bacteria from the animal but merely suppresses it, meaning, although the birds seem to recover, they continue transmitting the infection to other birds in the flock.”

The doctor said that mycoplasma and infectious coryza though caused by bacteria are difficult to differentiate from each other due to the similarity in their symptoms and effects.

These diseases are also difficult and expensive to diagnose in the lab.

“Are they treatable?” I enquired.

“Although difficult to treat and control, with intensive treatment and hygiene, they are manageable,” he responded.

Based on his advice, Cleophas my farm manager commenced treatment with an antibiotic called Sulphonamide- trimethoprim in drinking water for infectious coryza.

ALWAYS CONSULT PROFESSIONALS

For mycoplasma, the vet recommended a different antibiotic called Tiamulin in drinking water for five days. This last antibiotic is not available in agrovets and can only be sourced from the manufacturer, Ultravetis.

“While Tiamulin kills mycoplasma germs, it does not kill infectious coryza germs,” said Dr Mugachia. Now a packet of 55g retails for Sh850, meaning for four packs, I need to cough up Sh3,400. For now, I am still waiting for this drug to be delivered.

Another thing he advised, “Response to treatment should be monitored closely by your regular vet and if treatment fails to work, the site should be cleared of all the birds for three months to disinfect it.”

He also said that because overuse of antibiotics in animals threatens public health, farmers should always consult professionals.

Coming from a medical background where the problem of antibiotic resistance is rampant, I found this advice invaluable.

Another thing Dr Mugachia told me is that there is an effective vaccine against infectious coryza. For all this, I parted with Sh5,000 consultation fee.

For the 200 laying hens that were not showing signs of disease, he recommended a dose of multivitamins to synergise recovery.

It seems this has worked because, in addition to de-worming the hens, the laying rate has shot up from a low of about five to 15 per cent to over 50 per cent in one week.

For now, I can only wait to see the results of the treatment he recommended and I hope that I will not depopulate the flock to start from scratch.