BACKGROUND Although the epidemiology of scrapie has been broadly understood for many years, attempts to introduce voluntary or compulsory controls to eradicate the disease have frequently failed. Lack of precision in defining the risk factors on farm has been one of the challenges to designing control strategies. This study attempted to define which parts of the annual flock management cycle re...

Information on the physiological ecology of grass-dominant pastures has made a substantial contribution to the development of practices that optimise the amount of feed harvested by grazing animals in temperate livestock systems. However, the contribution of ecophysiology is often under-stated, and the need for further research in this field is sometimes questioned. The challenge for ecophysiol...

In grazing systems, heterogeneous distributions of forage resources and faeces result in localised accumulations of nutrients and parasites (both macroparasites and microparasites), creating trade-offs between the costs of exposure to infestation or infection and the benefits of nutrient intake. Each contact between livestock and faeces in the environment is a potential parasite/pathogen transm...

An integrated management system involving cattle, ewes and lambs developed to minimise levels of parasitic nematode contamination of pasture was evaluated in a 2-year (1989-1991) study. Four experimental farmlets were managed as self-containcd units over a May-May year. Over the two years, stocking rate averaged 15 su/ha and cattle:sheep ratio 35:65. Three treatments (lambs regularly drenched, ...

Pasture biomass is an important quantity globally in livestock industries, carbon balances, and bushfire management. Quantitative estimates of pasture biomass or total standing dry matter (TSDM) at the field scale are much desired by land managers for land-resource management, forage budgeting, and conservation purposes. Estimates from optical satellite imagery alone tend to saturate in the cov...

A variety of management options are used to minimize losses of nitrogen (N), phosphorus (P), and other potential pollutants from agricultural source areas. There is little information available, however, to indicate the effectiveness of these options (sometimes referred to as Best Management Practices, or BMPs) on basin scales. The objective of this study was to assess the water quality effecti...

Brazil has the largest commercial beef cattle herd in the world (over 190 million head in 2006) [1], with cultivated pastures occupying about 150 million hectares of its territory [2]. On a biome basis, the most extensive pasture occupation is found in the Cerrado (~ 546,251 km, amounting to about 26.8% of the total biome area and 36.8% of the total pasture area in Brazil), the Brazilian savann...

Runoff from a cow-calf pasture in eastern Nebraska was monitored for total coliforms (TC), fecal coliforms (FC), and fecal streptococci (FS) during 1976, 1977, and 1978. Bacteriological counts in runoff from both grazed and ungrazed areas generally exceeded recommended water quality standards. The FC group was the best indicator group of the impact of grazing. Rainfall runoff from the grazed ar...

Agricultural intensification is critical to meet global food demand, but intensification threatens native species and degrades ecosystems. Sustainable intensification (SI) is heralded as a new approach for enabling growth in agriculture while minimizing environmental impacts. However, the SI literature has overlooked a major environmental risk. Using data from eight countries on six continents,...

Two, 8-week experiments, each using 30 lactating Holstein cows, were conducted to examine performance of animals offered combinations of total mixed ration (TMR) and high-quality pasture. Experiment 1 was initiated in mid October 2004 and Experiment 2 was initiated in late March 2005. Cows were assigned to either a 100% TMR diet (100:00, no access to pasture) or one of the following three formu...