Eighteen multiparous Holstein cows were used to study the long term effect of reducing
dietary P concentration on intake of D Mand milk yield,on blood levels of inorganic
phosphate(Pi), Ca,vitaminD3, parathyroid hormone (PTH) as well as assessing bone
turnover by the use of bone formation marker osteocalcin (OC) and bone resorption
markercross-linkedcarboxy-terminal telopeptideoftypeIcollagen(CTX).Treatments
were initiated 3 weeks before expected calving, and cows were followed until week 36
after calving. Indryperiod treatments were Low P(LP)(1.7gP/kgofDM),MediumP(MP)
(2.1gP/kgDM) and High P(HP) (2.5gP/kgDM).