Botanical and nutritive content in diets of sheep, Angora goats, Spanish goats, and deer grazing a common pasture

Abstract

A study was initiated in August 1975 to illuminate the dietary interrelationships among four kinds of small ruminants of the Edwards Plateau of Texas. Interrelationships were based on the botanical and nutritive composition of diets collected monthly over a 1-year period in a pasture where available forage allowed maximum expression of dietary preferences. The study area was located in a pasture regularly grazed by cattle, sheep, and goats for 12 months and rested 4 months. Availability of herbaceous forage was measured each month prior to diet collections. Browse availability was measured for five selected periods throughout the year. Botanical and nutritive composition of livestock diets was obtained from esophageally cannulated sheep, Angora goats, and Spanish goats. Botanical composition of deer diets was determined by the feeding-minutes method. Nutritive content was estimated by hand-plucking plants species and parts that tame deer were observed to graze. Grass standing crop was highest during late summer (3,300 kg/ha) at initiation of the study and lowest (1,951 kg/ha) in winter. Growth exceeded utilization for only 2 months during the spring of the year. Forb availability exceeded 50 kg/ha only from August through November and April through July. Edible browse availability was dominated by Plateau oak and was highest (189 kg/ha) in late summer and lowest (53 kg/ha) in winter.