Sheep and goat grazing diets on an annual Mediterranean grassland containing tall wheatgrass (Thinopyrum ponticum (PODP.))

Abstract

Sheep and goat grazing diets on an annualMediterranean grassland containing tall wheatgrass (Thinopyrum ponticum (PODP.)). Cienc. Inv. Agr. 45(3):240-250. The development of mixed grazing systems is an interesting alternative for the utilization of rangelands with ecological and/ or economic limitations; therefore, the study of patterns and eating habits of different species in the same grazing area is important. A mixed grazing study was carried out on a Mediterranean grassland sown with Thinopyrum ponticum 30 years ago (Rinconada de Maipú, Chile 33º 28'S; 70º 51ʼ W) with the purpose of quantifying the botanical composition, dietary overlap and selectivity indexes of the main grass species consumed by goats and sheep. Trophic behavior was studied in seven young Suffolk Down rams, seven young Merino-Precoz rams and seven young Boer-Criollo bucks grazing together during three grassland phenological stages. During the grassland vegetative stage, diets were mainly composed of annual grasses and forbs. Perennial grasses dominated the animals' diets during the reproductive and dry grassland stages. The diversity of the goats' diets was higher than that of the sheep, demonstrating greater plasticity in their dietary habits. However, in this environment, both species behaved as generalist herbivores. The level of diet overlap between the sheep and goats was high, especially when grazing during the grassland reproductive and dry phenological stages, suggesting potential competition during lower forage quality stages.

Summer Diet of Horses (Equus ferus caballus Linn.), Guanacos (Lama guanicoe Müller), and European Brown Hares (Lepus europaeus Pallas) in the High Andean Range of the Coquimbo Region, Chile

“…The data presented by Uresk [ 58 ], in the dietary study of the black-tailed hare ( Lepus californicus ), report a lower number of dietary items (13 plant species), but as in our results, the intake of a dicotyledonous grass ( Achillea millefolium ) [ 58 ]. This suggests that this herbivore has a high amplitude of trophic niche, but at the same time presents a selective behavior for some plant species, which would fulfill a nutritional role of production and a functional role as diet improvers [ 25 , 59 ]. Selections of plant species with high energy content associated with relative high levels of fat and protein are reported by Schai-Braun et al [ 60 ], which supports our affirmation.…”

Adaptive mechanisms of tall wheatgrass to salinity and alkalinity stress

“…There is little information regarding voluntary feed intake and diet selection of ruminants grazing tall wheatgrass swards. Evidence of tall wheatgrass being preferred (Borman et al, 1991) or deterred (Castellaro et al, 2018) among other fodder species on offer is scarce and has not been performed on the basis of current knowledge about leaf age and length as strong determinants of forage digestibility (di Marco & Agnusdei, 2010; Insua et al, 2018).…”

Botanical Composition and Diet Quality of the Vicuñas (Vicugna vicugna Mol.) in Highland Range of Parinacota, Chile

“…The study of the botanical composition of herbivores' diets represents an important aspect of their ecology and is relevant in the development of management techniques aimed at reducing the impact of animals on vegetation and on the environment [1,2]. By identifying the components of the diet of grazing herbivores, information is generated to determine key aspects of livestock management, including range carrying capacity, choice of grazing sites, estimation of trophic competition with other herbivores, assessment of the nutrient content of the diet, supplementation needs and prediction of the effects of overgrazing [2,3].…”