Vet on call: A good farm owner will always listen to the vet

Media reports have indicated that the top leadership of the United States took lightly repeated warnings from medical scientists that Covid-19 had the hallmark of a global pandemic never seen before.

The situation has compelled President Donald Trump to explain some ‘lighthearted’ media pronouncements he made on the disease even after it landed on American soil. He claimed this was to encourage Americans not to panic.

Unfortunately, the jury is out that he should have acted on advice from scientists from the onset.

I have noticed farm managers with a science background, such as veterinary doctors and veterinary paravets, find it difficult to communicate a “no” guided by the scientific unsuitability of instructions issued by the employer or a domineering client.

This often results in costly outcomes.

I had an interesting case three weeks ago on a large-scale dairy farm. The second-level manager reported by phone that there were two sick animals. One was a pregnant cow called Jane and the other a heifer named May.

Jane was showing difficulties in breathing, had swollen lymph nodes and high temperature. The fever dropped from a high of 41 to 40.5 degrees Celsius even after treatment. The cow was deteriorating and the manager was concerned it could die.

May was a heifer. She had poor appetite and scone-like stools, almost similar to a donkey’s. She had not been treated as other parameters appeared normal. The manager wondered whether the heifer could have been drinking inadequate water.

The reports were a bit interesting because the cows are zero-grazed with a very high level of hygiene and tick control.

I contacted the paravet, who had treated Jane. He said he had diagnosed east coast fever and given the standard drug combination therapy.

I considered the weight of the animal and doses of the drug he had given. I opined the cow should have recovered substantially and temperature dropped to just around normal.

I told George, the paravet, that Jane must have been having a mixed tick-borne parasitic infection that I call “the three musketeers”.

These are theileria that cause the deadly but treatable east coast fever, babesia that causes red water and anaplasma that cause anaplasmosis.

The treatment George had given must have knocked off theileria and anaplasma, leaving babesia to continue

SUSTAINED HIGH FEVER

flourishing. Theileria causes high fever of up to 42 degrees Celsius, swelling of lymph nodes and tearing. Babesia, on the other hand, causes lower fever and internal blood loss because the liver destroys infected blood cells.

I advised George to get back to the farm, review Jane and let me know the findings. He would also examine May and report to me before giving any treatment.

George’s findings led me to diagnose a mixed infection in Jane by the '”three musketeers”' while May indicated she only had anaplasmosis.

You see, Jane’s mucous membranes had started becoming yellow and George reported the rumen was moving.

However, when he placed his hand in the heart area, he felt the organ’s beat was heavy and fast. I advised him to treat for babesiosis.

In May’s case, George reported the mucous membranes were starting to turn yellow and the rumen was moving very weakly. Combining these signs with the hard scone-like stools, I confirmed my suspicion of anaplasmosis.

I advised George to treat for the disease. The following day, George confirmed the animals had responded well to treatment. They have since recovered.

The big question was, “How did the cattle get the infections yet they are well taken care of?” I asked Judy, the manager, what could have happened, but she did not have the history since the previous manager had left the farm

The answer came from the head stockman. He said that about two weeks earlier, the pregnant cattle and heifers had been grazed in a harvested oat field.

One of the farm directors had instructed the previous manager, who was also a paravet, to have the animals open-grazed to reduce the cost of feeding.

Incidentally, it was raining heavily and the manager carried out the instructions. My puzzle had been solved.

The animals were washed with acaricide to control ticks but they were grazed in the rain. The rain washed off the tick control chemical and presented an opportunity for the ticks to feed on the cattle. The ticks infected the cattle with the parasites that are transmitted in the tick saliva.

The outcome was infection of two cows with deadly tick-borne diseases that almost cost the loss of one cow. In addition, Jane aborted due to the sustained high fever.

The other outcome was the heavy cost of treating the disease, particularly east coast fever. It costs over Sh10,000 per animal to treat a combination infection of east coast fever, babesiosis and anaplasmosis.

This costly problem could have easily been avoided if the manager had advised the director that it was scientifically unsuitable for the animals to graze in the rain in an area where ticks and tick-borne infections are known to exist.