Last week, I shared four cases I saw for the first time this year. I requested farmers and vets to contact me if they had encountered the syndrome I explained in pigs.
Two readers wanted to know if the incidents could be a result of climate change or development of antibiotic resistance by pathogens.
Medical professionals should try and understand why diseases occur and if there are changes in occurrence trends.
While a single incidence of a disease occurrence can flag a change in patterns, a change requires scientific investigation to be confirmed. This is a known as disease epidemiology.
Since I have not carried out thorough investigations, it is not possible to state if there has been a change in occurrence of the diseases.
Nonetheless, two of the cases involving dogs were unlikely to be associated with global warming or antibiotic resistance because they were cancers of animals above eight years old.
Oliver, a pig farmer in Makueni, wanted to know if the disease could spread to his county. Farmers and traders should know that movement of animals and animal products promotes disease spread.
Oliver may feel safe in that the syndrome I described was only on one farm, affecting mainly pregnant pigs.
Njuguna from Kiambu said he was on the verge of losing his pigs. He thought the syndrome I described was responsible. He had 20 pigs and 18 died in two weeks.
The disease signs included bleeding spots under the skin and on the surfaces of the intestines, stomach and heart. He said his neighbour’s pigs had died with similar signs.
I advised Njuguna to report the disease to the authorities immediately. His animal health service provider had told him to sell the pigs for slaughter. The farmer, however, delayed to do so and I commended him for that.
Njuguna’s case points more to African swine fever. Once a notifiable disease is confirmed, the national and county directors of veterinary services ensure intervention measures are taken to check the outbreak, treat the animals and give protective treatment to healthy ones.
Kamau is a consultant and has long experience in pig production. He has on a few occasions seen pigs with the syndrome.
Most of the cases he had seen had resolved without a confirmatory diagnosis as they were thought to be bacterial infections.
A different perspective came from Hose, a paravet in Narok. He said he had encountered the syndrome and was advised by a doctor that it was most likely porcine parvovirus (PPV). The pigs appeared to recover when he used the PPV vaccine.
I explained to him it was unlikely to be PPV. A PPV outbreak has five key indicators comprising small piglet litters and repeat breeding. Served pigs lose all or some embryos by the 35th day of pregnancy. Sows farrow mummified foetuses.
There is increased number of stillbirths per farrowing and piglets with low birth weights. Abortions are not a dramatic feature of PPV.
Hose’s case could have been a viral infection where the pigs developed immunity and managed the virus naturally. Farmers should vaccinate their breeding pigs against PPV.
Dr Juliet, who has worked with pig farms, said she had seen the syndrome once but her investigation did not yield a specific diagnosis.
She suspected it could be a viral infection that caused depression of immunity in the sows, resulting in general bacterial infection. I am inclined to postulate the same.
I continue to receive enquiries. Most want to know the cause of the disease and how to protect their animals. Farmers should practise good hygiene, vaccinate their animals and source animals from healthy herds.
BREEDING AND HEALTH RECORDS
I received a follow-up call from the Kiambu County Director of Veterinary Services (CDVS). He requested me to brief the sub-county Director of Veterinary Services (SCDVS) of the area the farm is. In terms of disease outbreak investigation, this is an order.
We visited the farm with the SCDVS – Dr Lydiah Nyaga and Dr Juliet who is a microbiologist. Our first face-to-face briefing was the initial step of the official outbreak investigation.
Dr Nyaga assured us that county authorities would liaise with the National Director of Veterinary Services (DVS) to make a confirmatory diagnosis of the problem.
A scrutiny of the breeding and health records showed three of the pigs were served by the same boar while the other two had artificial insemination. The boar had fever and loss of appetite two weeks before the sows got sick.
It recovered after treatment with antibiotics. We advised the manager to rest the boar from breeding until we confirmed the disease affecting sows.
The sick pigs we had treated earlier with antibiotics were recovering. We attributed the response to control of bacterial infection. One sow was in the process of abortion. I terminated the pregnancy to save the mother.
Four of the five surviving piglets of one sow had died. The last died as we arrived at its pen.
There were no new cases on the farm. In fact, six more sows had since my last visit farrowed between 12 and 14 healthy piglets.
We concluded our meeting, recognising our joint end of year challenge; to follow up on the outbreak investigation till we confirm the cause of the disease syndrome on the