Grazing Behavior and Diet Preference of Beef Steers Grazing Adjacent Monocultures of Tall Fescue and Alfalfa: II. The Role of Novelty

Abstract

Domestic ruminants select a mixed diet when grazing heterogeneous pastures. Adjacent monocultures allow diet preference to be evaluated without certain constraints that could influence diet selection; however, few forage species have been evaluated. Adjacent monocultures of tall fescue (Festuca arundinacea Schreb.) and alfalfa (Medicago sativa L. ssp. sativa) were used to test the theories that selection of mixed diets is influenced by a plant's “novelty,” and that regardless of forage species, cattle will have a partial preference for legumes over grasses. Cattle without previous experience eating alfalfa spent 78% of total grazing time eating alfalfa, whereas after having experience grazing alfalfa they spent less (P = 0.04) time grazing alfalfa (72%). Overall, proportion of the day spent grazing was less (P = 0.001) when alfalfa was novel (40%) than when steers were experienced with both forages (46%). Proportion of the day spent idling was greater (P < 0.001) when alfalfa was novel (35%) than when both forages were familiar (26%). The proportion of grazing time in alfalfa was greater (P = 0.02) in the afternoon (76.8%) than in the morning (72.1%), differing from previous studies that reported a decline in legume preference over the day with an increased grass preference in the afternoon. Application of adjacent monocultures in production systems would benefit from additional research on performance of cattle grazing in this paddock arrangement.

Diet Composition and Dry Matter Intake of Beef Steers Grazing Tall Fescue and Alfalfa

“…This indicates that even though concentrations of n‐alkanes C 27 and C 33 were low, they did provide additional discrimination between the forages when only n‐alkanes were considered. When only C 29 and C 31 n‐alkanes were used, however, over 66% of the diet composition estimates were calculated as either 100% alfalfa or 100% tall fescue, which we know was not the case based on behavioral observation (Boland et al, 2011). Using only the two n‐alkanes, C 29 and C 31 , did not provide enough discrimination between the two forage species for NNLS to estimate diet composition.…”

Spatial Arrangement of Forages Affects Grazing Behavior of Beef Heifers Continuously Stocked at Low Stocking Rate

“…As indicated by Chapman et al (2007), the spatial and temporal separation approaches also allow entertaining the possibility of applying species‐specific management to the individual components to help control botanical composition. Similar studies in our laboratory (Boland et al, 2011a,b; Boland and Scaglia, 2011), and at Mississippi State University (Solomon et al, 2011, 2012), followed a similar approach.…”

Comparison and Diet Preference of Novel Endophyte‐Infected Tall Fescue Cultivars

“…Forage preference measurements have been recorded by visual scoring (van Santen, 1992;Shewmaker et al, 1997), and also by clipping and weighing the remaining forage after grazing (Smit et al, 2006). It is possible that these methods could be augmented with GPS technology, which can be implemented without disrupting animal grazing behavior during periodic measurements (Turner et al, 2000;Boland et al, 2011;Augustine and Derner, 2013).…”