in the current iranian poultry industry, antibiotics are the most frequently used additive in feeds to increase the productivity. regarding the negative effects on human health due to consuming chicken whose feeds contain antibiotics, finding an appropriate alternative is of a great importance. this study aims to find an appropriate and harmless feed additive to increase the quality and quantit...

Managed forests are increasingly being used for recreation. As a result, foresters may be expected to tailor silvicultural treatments to accommodate specific recreation preferences. To better understand changes in hiking and camping quality in the years following a harvest, six sites on the Oregon State University's research forest were evaluated annually for 11 years. Multiple comparison and r...

growing urban population may cause severe resource as well as social impacts. so, managers at urban parks are often faced with the fundamental question of what level of visitor use can be accommodated in a park or recreation area so that natural and cultural resources and the quality of the visitor experience do not deteriorate to unacceptable levels. within the outdoor recreation ?eld, this is...