Clinical and productive implications of urinary pH of high-producing dairy cows during the prepartum period

Abstract

Prepartum urinary pH monitoring is an efficient and economical method to evaluate acidogenic diet efficiency and its benefits. Therefore, the objective of this trial was to correlate prepartum urinary pH data of high-producing dairy cows with blood calcium levels, metabolic diseases incidence in the first ten days of lactation, lactation number and milk yield in the postpartum. One hundred and five dairy cows belonging to two commercial herds were supplemented with anionic salt in the last 21 days of pregnancy. Even with the prepartum anionic salt supplementation, the dietary cationic-anionic difference (DCAD) was estimated at +125 mEq/kg of dry matter. Blood samples were collected on days 1, 2, 5 and 10 after calving to evaluate total calcium (Ca) concentration. During the first 10 days of lactation, individual metabolic diseases and daily milk yield were registered. Average urinary pH was 8.2 ± 0.4. Average serum Ca on days 1, 2, 5 and 10 were 10.29, 10.32, 11.07 and 11.22 mg/dL, respectively. From the 105 monitored cows, 44.8% showed at least one disease event in the first 10 days postpartum. There were no significant correlations (P>0.05) between prepartum urinary pH and blood Ca levels, as well as no significant associations (P>0.05) between prepartum urinary pH and the metabolic diseases incidence.