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Published on: July 31, 2021
Vitamin B12 absorption and metabolism in milk-fed lambs
T M Gruner1, J R Sedcole, J M Furlong
1Animal and Food Sciences Division, Lincoln University, Canterbury 8152, New Zealand. tini.gruner@scu.edu.au
New Zealand Veterinary Journal
|March 3, 2009
Summary
Pre-ruminant lambs absorb and retain vitamin B12 poorly from milk. Continuous supplementation may be most effective for preventing deficiency, even with low tissue concentrations.
Area of Science:
- Animal Nutrition
- Biochemistry
- Veterinary Medicine
Background:
- Vitamin B12 is crucial for metabolic pathways, including propionate metabolism.
- Understanding vitamin B12 absorption and retention in pre-ruminant lambs is vital for optimizing their nutrition.
- Propionate metabolism may influence vitamin B12 status in young ruminants.
Purpose of the Study:
- To quantify vitamin B12 absorption and retention in milk-fed lambs.
- To investigate the effect of propionate metabolism activation on tissue vitamin B12 levels.
- To determine the efficiency of oral and intramuscular vitamin B12 supplementation in lambs.
Main Methods:
- Three experiments involving newborn lambs fed milk substitute with or without propionate.
- Administration of vitamin B12 via intramuscular injection or oral supplementation at various doses.
- Measurement of plasma and liver vitamin B12, methylmalonic acid (MMA), and transcobalamin II/haptocorrin concentrations.
Main Results:
- Propionate supplementation increased plasma vitamin B12 in supplemented lambs but not in unsupplemented ones.
- Lambs with marginal vitamin B12 levels could metabolize propionate and maintain normal MMA.
- Oral absorption of vitamin B12 was low (<10%), and retention was poor, irrespective of tissue concentrations.
Conclusions:
- Pre-ruminant lambs exhibit poor absorption and retention of vitamin B12 from milk.
- Even with low tissue vitamin B12, lambs can metabolize propionate if absorption rates are managed.
- Continuous, modest vitamin B12 supplementation is recommended for preventing deficiency in lambs.
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