Cobalt, Vit B12
By Dr Mackie Hobson BSc(Agric),BVSc

1. Nutrition

Cobalt (Co) deficiency in Angora goats is seldom seen largely due to the use of lucerne (good cobalt source) in many Angora goat production systems.

Cobalt is an essential constituent of vitamin B12. Vit B12 (cyanocobalamin) is manufactured in the rumen by the rumen microbes. If Co in diet is lower than 0.11ppm DM basis a deficiency will occur.

Deficiencies occur:

• In sandy soils in the Southern Cape and Humandorp.
• Grains and concentrate animal feeds are low in Co.
• Co deficiencies in the Graaff-Reinet/Murraysburg area

Legumes (Lucerne) are a good source of Co.

Vit B12 is stored in the liver. And can last 3-4 months.

Role of Vit B12

Propionate is produced in the rumen as the result of fermentation of carbohydrates which in turn is converted to methyl malonate. The critical step is the conversion of methyl malonate to succinate.

This can explain why Vit B12 injections to sick or goats with a poor functioning rumen often helps.

Deficiencies cause the rate of proprionate clearance from the blood to be poor which supresses the appetite. B12 injection stimulates the appetite overnight.

Vit B12 is also important for the production of Methionine which is essential for mohair growth. See Article on Methionine on the SAMGA website https://www.angoras.co.za/article/importance-of-methionine-in-angora-goats#260

Signs of Cobalt deficiency

Younger goats, especially weaned kids can be more susceptible to deficiencies.

• Reduced appetite (poorer growth)
• Reduced mohair growth
• Polioencephalomalacia (Thiamine deficiency) See article on the SAMGA website https://www.angoras.co.za/article/polioencephalomalacia-pem#217
• Fatty liver -  See article of ‘floppy kid syndrome’ on the SAMGA website

https://www.angoras.co.za/article/floppy-kid-syndrome#257

Determining Vit B12 levels

• Liver samples
• Serum blood samples reflect cobalt intake when liver levels are low. The goats must not be starved before sampling

Treatment

Because a regular dietary intake of cobalt required oral dosing is not effective.

Mineralised anthelmintics contain about 2-3mg cobalt/10ml and are not a sufficient form of supplementation.

• Vit B12 injections will boosts for a least a month
• Feed Lucerne (Legume)

Ref: West, Bruere, Ridder (Vetlearn) Health , disease and Production