Studiet viser at man kan give koen en mere behagelig afgoldning ved hjælp af oral indgift af en række salte indkapslet i en bolus.
Ved oral indgift af en række salte indkapslet i en bolus, mindskes foderindtag og mælkeproduktion, og hvis det anvendes ved afgoldning, reducerer det trykket i yveret og forøger liggetiden de første 24 timer efter afgoldning.
The aim of this study was to evaluate the potential of oral acidogenic mineral boluses (196 g) containing anionic salts to facilitate the transition from lactation to the dry stage by inducing a mild and temporary metabolic acidosis at dry-off. In experiment 1, 84 lactating cows were randomly allocated to 1 of 3 treatment groups consisting of an oral administration of 0, 1, or 2 boluses 5 d before dry-off to evaluate the effects on milk production. In experiment 2, 16 lactating cows were involved in a crossover study to evaluate the effects of the administration of 2 boluses on milk production, feed intake, and urine pH. In experiment 3, 152 lactating cows were allocated to 1 of 2 treatments (control: no treatment; bolus: 2 oral boluses the day before last milking) to evaluate udder pressure, incidence of milk leakage, and lying behavior during the first days following dry-off. Also, milk yield in the subsequent lactation for all enrolled cows was recorded during the first 60 DIM. In experiment 1, cows receiving 2 boluses had the greatest reduction in milk production (−2.56 kg/d of milk) compared with those receiving 1 bolus or no treatment (−1.15 and −0.23 kg/d, respectively) the second day after bolus application. In experiment 2, the application of oral boluses decreased feed intake of cows during the first 3 d following treatment, and milk production was reduced on d 2 and 3 after bolus application. Reduced urine pH at 8 and 24 h after treatment was observed in bolus cows compared with control cows. In experiment 3, bolus cows had lower udder pressure after drying off, but incidence of milk leakage did not differ between treatments. Bolus cows had an additional 85 min of lying time in the 24 h following dry-off. Serum P and β-OH-butyrate concentrations were lower in bolus cows than in control cows after dry-off, but no other differences in blood parameters between treatments were observed. Also, no differences in milk yield in the subsequent lactation were observed between treatments. It is concluded that oral bolus application diminishes feed intake and milk production, and, if applied at dry-off, it decreases udder pressure and increases lying time during the first 24 h after dry-off.