Nakuritis: Why It is unique to Nakuru County

The age of pasture also determines levels of cobalt. [iStockphoto]

Dear Dr Othieno, I am a dairy farmer from Nakuru County and a regular reader of your column. 

I recently chatted with my neighbour when he asked if I supplemented my animal feed with cobalt.

He warned me that failing to do so would put my animals at risk of Nakuritis. I did not believe such a condition existed until another farmer intimated that a veterinary doctor had diagnosed his animals with cobalt deficiency, manifested by wasting away in his goats and cattle.

I provide mineral licks to my animals and have not observed any signs of the disease.

Is there such a disease, and if so, what can I do to prevent it from occurring on my farm? Also, could the mineral licks be the reason I have not experienced it? [John Njoroge, Nakuru County]

Thank you, John, for reading Smart Harvest and for taking the time to write back to us. Yes, there is indeed a disease called Nakuritis, which is caused by cobalt deficiency.

It is also possible that your mineral supplementation has helped prevent cobalt deficiency in your herd. This condition is endemic to Nakuru, hence the name “Nakuritis.” 

The good news is that the disease can be prevented and treated if it occurs.

Cobalt deficiency is also known as Vitamin B12 deficiency because cobalt is a constituent of Vitamin B12. It occurs due to pasture being deficient in cobalt due to soil being poor in the mineral or because of the general health condition of the animal.  

Vitamin B12 is important in the digestion of cellulose, which is a major component of feeds. Vitamin B 12 is also an important co-enzyme and plays a role in the metabolism process.   

The type of soil will affect the availability of cobalt.

Cobalt is available in large quantities in poorly drained, waterlogged soils but is scarce in deep, sandy soils.

Reduction of cobalt and subsequent deficiency can occur due to over-liming of soils, increasing the pH to above 6.0.

The age of pasture also determines levels of cobalt. For instance, second-cut silages contain a higher content of cobalt compared to first-cut silage.

Young animals have low reserves of cobalt and will require more of this mineral for growth. Also, heavy worm infestation results in high incidences of cobalt deficiency.  Shoats (sheep and goats) are more susceptible to cobalt deficiency than cattle. 

Young stock deficient in cobalt will grow slowly, while adult animals will lose their appetite and grow thin.

If not treated, the animal will lose muscle weight and may die.

Anemia, shown by pale mucus membranes, is a common sign of cobalt deficiency. An animal with cobalt deficiency will be unthrifty, have scaly ears and excessive secretion of tears with matting of the wool below the eyes.

The wool will easily break, while lactating animals will register a drop in milk production.

Other signs include diarrhoea in calves and eating of abnormal objects like tree barks, leaves, soil or dirt (pica).

A veterinary doctor will treat cobalt deficiency by giving a Vitamin B12 injection, which is available in the market alongside multivitamins.  Response is normally good.

If you are in a cobalt-deficient area, you may consider giving oral solutions. This needs to be given every two weeks. To overcome the challenge of repeated administration, slow-release boluses–intraruminal cobalt–can be used.&nbsp

When you suspect cobalt deficiency, start by establishing whether the soil is deficient.

Confirm that cobalt deficiency is the cause of the observable clinical signs by eliminating other causes, such as worms or diseases. 

[Dr. Othieno is a veterinary surgeon and currently the head of communications at the Food and Agriculture Organisation (FAO) Kenya. The views expressed here are not necessarily FAO’s]