The relationship between diet and retained placenta in cows

Abstract

Retained placenta (RP) is one of the most common complications occurring in the post-partum period in cows. Beside other reasons, many authors stress the influence of diet on the incidence of RP. However, the role of minerals and vitamins fed at this time on subsequent fertility is poorly understood. As nutritional causes of RP are due primarily to the diet fed the last 6 to 8 weeks before calving, the aim of this paper was to investigate the relationship between diet in dry and transition periods and subsequent occurrence of RP, as well as in the time of introduction to lactation in fresh cows, with special emphasis on content of minerals and vitamins in diet. The investigation has been carried out on a big dairy farm situated on the east of Croatia with 1 775 Holstein-Frisian (HF) cows in duration of one year. Diet samples from dry period (DP), from period approximately from the 21st day before calving till the day of calving (BC) and period of introduction to lactation (IL) were subjected for analysis of calcium (Ca), phosphorous (P), selenium (Se), iodine (I) and vitamins A, D3 and E. The observed rate of cows with RP on the investigating farm was rather high (16.55%). High diet concentrations both for Ca and P in DP and BC periods (0.98 and 0.62% of Ca; 0.37 and 0.52% of P, respectively), combined with low concentration of vitamin D in DP and BC periods (12 800 and 14 400 IU/day, respectively), as well as low concentration of Se in DP and BC periods (0.08 and 0.07 mg/kg, respectively) combined with low concentration of vitamin E in DP and BC periods (160 and 180 IU/day, respectively) were identified as critical factors that could have contributed in influencing high incidence of RP on the investigating farm.