Macrae reveals UK dairy cow study outcome
A study into UK dairy cows has shown one in three were suffering clinical or subclinical ketosis in the first 50 days of lactation, according to metabolic blood profiles taken over a five year period. Dr Alistair Macrae, from the Royal (Dick) School of Veterinary Studies, told delegates at the World Buiatrics Congress that this condition puts dairy cows at risk from reduced fertility and performance.
Dr Macrae used metabolic profile analyses accumulated through the Dairy Herd Health and Productivity Service (DHHPS). The DHHPS collected blood samples from over 40,000 individual cows, from over 1200 commercial UK herds between 2006 and 2011. The samples were collected in order to investigate the prevalence and extent of negative energy balance in cows before calving, and in lactation.
The prevalence of clinical and subclinical ketosis can be revealed by the levels of betahydroxybutyrate (BHB) and Non-Esterified Fatty Acids (NEFAs) in the blood, a direct measurement of negative energy balance in cows. Dr Macrae explained there are two crucial periods where cows are most at risk of negative energy balance. These are in the transition period 10 days prior to calving, and in the first 21 days after calving.
Macrae says: “Attention to the nutritional management of the transition cow is essential to help reduce the effects of negative energy balance on cow performance and future fertility."
The BSAVA has opened submissions for the BSAVA Clinical Research Abstracts 2026.
