Vet on call: Dealing with gapeworms and porcine parvovirus

Saturday August 01 2020
vet img

Students of the Eldoret Technical Training Institute feed pigs that they keep in the institution's farm in Kapseret, Uasin Gishu County. For vaccination to be effective, pigs should be immunised 14 days before being served. PHOTO | FILE | NATION MEDIA GROUP


Four years ago, I started writing this column, sharing with farmers and other interested parties in

The livestock industry various aspects that affect production and profitability.
Most of the articles have been on livestock diseases, nutrition and management and the solutions to the challenges that farmers encounter.

I have also presented policy issues in livestock production and marketing.

Obviously, most articles relate to production and health of the animals as these comprise the major component of the livestock value chain.

It is motivating when I get feedback from farmers and other readers. It gives me the confidence to continue sharing, knowing the information is useful. 

The feedback I get comes from every corner of the country. Sometimes it is immediate, other times it takes weeks or even years. 


Last week, I got a call from Daisy in Kakamega and she referred to my article on gapeworms published on October 12, 2018.

Daisy said her chickens were gaping. She searched the internet and came across the article.

Then she opened up a dead chicken, she found the worms in the trachea, thus wanted a prescription for gapeworm infestation, noting that the birds had been treated with antibiotics and some worm medicine but the problem had persisted.

Gapeworms are often missed by many animal health service providers, who treat affected birds for pneumonia. 

It is advisable to rule out the problem in any case of a pneumonia-like condition in chicken.

I advised Daisy to visit the nearest agrovet shop and request for Levermisole poultry formulation.


The product is effective in gapeworm treatment because it is absorbed from the intestines into the bloodstream in sufficient quantities to kill the worms lodged in the trachea.

From Siaya, Otieno called to confirm that he had managed to keep at bay “the three musketeers”, that is, East Coast fever (ECF), babesiosis or red water and anaplasmosis (gull sickness), from his cattle for two consecutive years. 

He was responding to my article of July, 2017. Since he understood the diseases, he diligently washes his cattle once per week with a suitable acaricide.

Maina rears indigenous chickens for meat in Uasin Gishu. Two weeks ago, he told me he had read my article in June 2019 about a disease that causes nodules on a chicken’s head, neck and legs. 

He had not experienced the disease until last week and wanted to know its treatment. I explained to him the disease is caused by the fowl pox virus and like most viral diseases, has no specific cure. 

I prescribed antibiotic and multivitamins to give in water. I also advised him to always vaccinate his birds as required to prevent the infection.

The show-stopper feedback came from Asunta, a farmer in Kirinyaga. I shared the story of her pig herd on February 8. 

She was distraught after the herd was attacked by what I diagnosed as porcine parvovirus based on the clinical findings and history of abortions, dead piglets at birth and mummified foetuses.


Between July 2019 and January, Asunta’s 19 sows had given birth to 278 piglets but only 76 had survived. 

Even then, some of the survivors were still weak and more were likely to die before attaining slaughter maturity. In addition, she could not select breeding stock from that lot of pigs.

The farmer found laboratory investigation of the problem too costly and opted for my clinical diagnosis and confirmation by treatment, which comprised vaccination of the sows and boars against porcine parvovirus.

You see, when laboratory diagnosis is a serious constraint either due to unavailability or poor accessibility of services or being unaffordable to the farmer, it is ethical for the doctor to do clinical diagnosis and confirmation by treatment.

It simply means if the problem is resolved through treatment, then it is deemed to have been confirmed. 

This form of treatment is, however, discouraged because in diligent disease control, there should be laboratory evidence of presence of the disease-causing agent. 

Asunta vaccinated her pigs as I had advised, though a few were inseminated before full vaccination. 

For vaccination to be effective, pigs should be immunised 14 days before being served. At the time, I cautioned she could end up with some undesirable outcomes with the sows which were improperly vaccinated.

Sure enough, sometime in May, the pigs disappointed Asunta with dead piglets at birth, but she hung on with hope on the properly vaccinated pigs. The first happy call came on June 8.


Asunta was very excited. The first properly vaccinated sow had given birth to 15 healthy piglets two days earlier. They were all doing well. 

The following day, another sow gave birth to 18 piglets and only one was very weak. The weak one appeared to have nestled into a position in the uterus poorly supplied with blood because it was otherwise properly formed. 

That challenge is often seen when sows give birth to more than 16 piglets.

In the following weeks, all the properly vaccinated sows gave birth to more than 12 healthy piglets each, except one. 

Asunta was overjoyed but at the same time apprehensive about the one odd and last sow to give birth. The sow’s farrowing was an anti-climax to a problem solved. It gave birth to 11 blind piglets. 

All were well-formed and otherwise looked healthy, but their eyelids were sealed shut. They had failed to separate into the usual two halves.

Unfortunately, it is very difficult and tedious to nurse blind piglets because they have to be hand-fed for a large part of their life. 

We agreed with Asunta she would do a cost-benefit analysis and decide if to rear the piglets or destroy them. 

The unopened eyes were most likely due to genetic defects possibly from inbreeding. It had nothing to do with the original problem.

- [email protected] /[email protected]