The aim of this study was to investigate a possible relationship between acid-base parameters in urine before parturition and the calcium level in blood shortly after parturition. Hundred dairy cows kept under identical feeding and housing conditions were monitored. The diet was based on grass and corn silage and hay ad libitum. Urine samples were taken on day 14, 7, and 3 before the estimated calving (day 285 of gestation) for the determination of pH, net acid-base excretion (NABE) and base-acid quotient (BAQ). Blood samples were taken within the first 12 h after calving for theanalysis of total calcium. During the period before parturition, the mean values of urinary pH, NABE, and BAQ were 8,63 ± 0,02, 232 ± 4 mEq/kg DM, and 4,75 ± 0,09, respectively. The pH and NABE values indicated a state of metabolic alkalosis of the cows resulting from the distribution of a diet with a high positive dietary cation-anion difference value (+ 474 mEq/kg DM). No significant correlations were observed between total calcium concentration in blood (1,92 ± 0,04 mmol/L) and mean values of urinary pH (r = 0,08; P = 0,416), NABE (r = 0,04, P = 0,719), or BAQ (r = -0,12, P = 0,234). The measurement of acid-base parameters in urine prior to parturition cannot be used to predict the level of blood calcium after parturition in cows under alkalotic condition. The determination of the NABE and BAQ parameters revealed similar information on the acid-base status of dairy cows as the measurement of the urinary pH.
Which stakeholders in the dairy sector have an influence on the productive life of dairy cows? Research results from FiBL and Agroscope suggest that broad-based cooperation is needed to create structures for a longer productive life.
Agriculture is aiming to reduce greenhouse gas and ammonia emissions. Agroscope showed that for dairy cattle housing, feed composition plays a role in these emissions as well as wind and temperature.
Lazzari G., Münger A., Eggerschwiler L., Borda-Molina D., Seifert J., Camarinha-Silva A., Schrade S., Zähner M., Zeyer K., Kreuzer M., Dohme-Meier F.
Tannin-containing feedstuffs like Acacia mearnsii and sainfoin (Onobrychis viciifolia) have a measurable impact in reducing methane emissions from dairy cows. However, since these feedstuffs in some cases lead to productivity losses, careful consideration must be given to their use.