Urinary ketone bodies determination as a tool for fast diagnosis of bovine subclinical ketosis and their relation with milk composition

Abstract

In early lactation, dairy cows high-yielding production suffer a variety of metabolic
changes derived from energy deficiency, due to poor dry matter ingestion and high milk production,
which are factors that predispose to ketosis. The main objective of the present paper was to relate
the presence of urine ketone bodies with beta-hydroxybutyrate serum levels and total solids in milk.
One hundred and forty multiparous Holstein-Friesian dairy cows high-yielding production belonging
to five commercial dairy herds in semi-intensive production systems of southern Brazil were used.
Sampling was done at 2, 5, 8 and 11 post-calving weeks. In each period samples of urine, blood and
milk were obtained for determination of ketone bodies, beta hydroxybutyrate and total solids,
respectively. Four different strips for testing ketone bodies in urine by sodium nitroprussiate method
were used. Also, urinary pH was measured. The proportion of cows positive to ketone bodies in
urine was 11,2%. BHB values above 1,2 mmol/L (cut-off point for ketosis) were present in 12,4% of
the cows. In conclusion, the subclinical ketosis in dairy cows may be diagnosed through the use of
strips for urine ketone bodies. No relation between ketone bodies and milk components were found
in the cow.