Effect of polyhalite on urine pH, dry matter intake, blood calcium (Ca) concentration and urinary Ca output when fed to pregnant and non-lactating dairy cows

• DOI: 10.1016/j.anifeedsci.2021.115119
• Publication Date: 2021-10-20T04:00:40Z
• Authors: E.S. Richardson; G. Ferreira; K.M. Daniels; H.H. Schramm; R.J. Meakin
• Keywords: 2. Zero hunger; 04 agricultural and veterinary sciences; 0405 other agricultural sciences; 6. Clean water

Abstract The objectives of this study were to determine urine pH, Ca concentrations in blood and urine, and dry matter intake (DMI) of non-lactating and pregnant cows consuming acidogenic diets containing polyhalite as an anionic salt during the prepartum period. Forty pregnant and non-lactating Holstein cows [739 ± 84 kg of BW and 22 ± 5 d before their expected calving date (ECD) at the beginning of the experiment], entering their second or greater lactation, were randomly assigned to 1 of 4 experimental diets in a randomized complete block design with 10 replicates. The experimental diets included: a diet with no acidogenic product and high dietary cation-anion difference (DCAD) that served as a negative control (CON; DCAD = 196 mEq/kg DM), a diet containing polyhalite and a neutral DCAD (NEU; DCAD = 7 mEq/kg DM), a diet containing polyhalite and a negative DCAD (NEG; DCAD = −172 mEq/kg DM), and a diet containing CaCl2 and a negative DCAD (CHL; DCAD = −167 mEq/kg DM). Urine pH decreased in cows consuming NEG (P