Stocking Rate and Fuels Reduction Effects on Beef Cattle Diet Composition and Quality

Abstract

An experiment was conducted to evaluate the influence of forest fuels reduction on diet quality, botanical composition, relative preference, and foraging efficiency of beef cattle grazing at different stocking rates. A split plot factorial design was used, with whole plots (3 ha) being fuel reduced or no treatment (control), and split plots (1 ha) within whole plots were grazed to three levels of forage utilization; (low) 3 heifers Á ha À1 , (moderate) 6 heifers Á ha À1 , (high) 9 heifers Á ha À1 , with a 48-h grazing duration. Grazing treatments were applied in August of 2005 and 2006. Cattle diet composition and masticate samples were collected during 20-min grazing bouts using six ruminally cannulated cows in each experimental unit. Relative preference indices indicated a strong preference for grass regardless of treatment and stocking rate. Grass consumption was lower in control pastures (P , 0.05) and tended (P , 0.095) to decrease with increased stocking rates. Shrub use was higher in control pastures displaying a quadratic effect (P , 0.05) due to stocking, whereas shrub use increased with stocking rate across all treatments. Cattle grazing control pastures consumed diets higher in crude protein compared to cattle grazing treated pastures (P , 0.05). In vitro dry matter digestibility values were lower (P , 0.05) in control sites and tended (P¼0.10) to decrease with increased stocking rates. In both control and treated pastures, bites per minute and grams consumed per minute declined (P¼0.003) with increased stocking, indicating foraging efficiency of cattle decreases with increased stocking rates. Our data indicated cattle grazing late season grand fir habitat types have a strong preference for grasses regardless of treatment or stocking rate. However, as stocking rate increased in both control and treated pastures, grass consumption decreased, shrub consumption increased, and foraging efficiency decreased.

Vegetation, Wildlife, and Livestock Responses to Planned Grazing Management in an African Pastoral Landscape

“…Moreover, these improvements were evident despite higher livestock stocking rates in planned grazing areas. This is significant because increased stocking would normally be expected to have negative effects on vegetation, cattle, and wildlife (Fynn & O'Connor, 2000;Mishra et al, 2004;Clark et al, 2013). These improvements suggest that the benefits of planned grazing practices can outweigh any undesirable effects of increased stocking rate.…”

Livestock Production Systems

“…Within the first decade of the twenty-first century, livestock production strategies have increased emphasis on livestock in conservation-oriented approaches to include (1) efforts to "engineer ecosystems" by altering vegetation structure for increased habitat and species diversity, and structural heterogeneity to achieve desired contemporary outcomes (Derner et al 2009(Derner et al , 2013; (2) use of targeted grazing involving application of a specific kind of livestock at a determined season, duration, and intensity to accomplish defined vegetation or landscape goals (Launchbaugh and Walker 2006), to reduce invasive annual grasses (Diamond et al 2010) and invasive weeds (Goehring et al 2010), as well as fuel reduction efforts (Davison 1996;Clark et al 2013); and (3) improvement of the distribution of livestock grazing across the landscape through the use of low-stress stockmanship methods using herding, strategic location of low-moisture supplement blocks (Bailey et al 2008), patch burn grazing in mesic (Fuhlendorf and Engle 2004) and semiarid (Augustine and Derner 2014) ecosystems, and foraging and learning through past experiences that increase the likelihood of animals learning to eat different plants (e.g., Provenza et al 2003). These ecological benefits from conservation-management applications have been attained without negatively impacting livestock production (Limb et al 2011;Augustine and Derner 2014).…”

Aboveground and belowground mammalian herbivores regulate the demography of deciduous woody species in conifer forests

“…Cattle are “bulk grazers,” with a diet composed largely of fibrous grasses and grass‐like species even during late summer as grasses senesce with summer drought in dry forests (Clark et al. ). By contrast, elk are “intermediate grazers,” with a broader diet of grasses, forbs, and shrubs in these same dry forests, and more pronounced switch to a shrub diet in late summer with senescence of grasses and forbs (Findholt et al.…”

“…Direct impacts of cattle on upland woody plant demography in the region have not received much attention, likely because cattle are primarily grazers of herbaceous species and deciduous woody species represent a very small proportion of their diet (Clark et al. ). Our study indicates that in addition to wild ungulates, cattle can also regulate woody species growth and size, despite their strong preference and selection for herbaceous vegetation.…”

“…, Cook ), would exert more pressure on cottonwood and willow than cattle, which are primarily grazers who prefer herbaceous species (Clark et al. ), resulting in greater effects by elk on the survival and growth of the two plant species. Moreover, we hypothesized that for both ungulates, increasing herbivore density would increase pressure on plant populations and have greater impacts on individual plant demographic performance.…”