Yellow-flowered lucerne: Properties and influence on performance and reproduction of ewes

Abstract

Conception rates and prolificacy of Finnish Landrace ewes fed yellow-flowered lucerne (Medicago falcata L.) pasture and silage prior to and during the mating period were compared with those of control ewes fed timothy (Phleum pratense L.) - meadow fescue (Festuca pratensis Huds.) pasture and silage. Ewes grazed pasture for four weeks and received their respective silage for 10 weeks indoors. Dry matter (DM) intake of lucerne silage was higher than that of grass silage (1.77 vs. 1.40 kg DM day-1). Timothy-fescue grass and silage analysed by a new modified method did not contain detectable amounts of plant oestrogens. In fresh and preserved lucerne, the amount of coumestrol was only moderate varying from zero to 59.5 ppm DM. Ewes fed lucerne received higher amounts of plant oestrogens than those on control feeding, but no differences in conception rate or lambing performance were found between the groups. However on lucerne, ewes conceived five days earlier (P=0.03) than control animals. Prolificacy of lucerne and control fed ewes averaged 3.13 and 3.19 lambs/ewe (P=0.76), respectively. There were no ewe health problems. The results suggest that the intake of yellow-flowered lucerne is good and the level of plant oestrogens has no detrimental effects on reproductive performance of adult Finnish Landrace ewes. ;