Forb selection differed by sheep breed and fell during the first week in each paddock.
Three ewe breeds compared
A study published on 26 March 2026 followed a 51-day grazing trial in northern mixed-grass prairie. It included 15 Dorper, 15 Rambouillet and 15 Hampshire ewes, plus 139 Dorper lambs. The animals grazed four three-hectare paddocks in sequence, staying nine to fourteen days in each according to available forage.
Forb selection changed with time
Dorper ewes selected forbs at 19.2% on average, compared with 7.7% for Rambouillet and 7.9% for Hampshire ewes. Observed forb selection fell from 17.4% to 1.7% around days seven to nine, while grass selection rose. Intake of the toxic plains larkspur remained low at 0.5% to 1.5% in the sampled diets.