*Texas A&M researchers continue to learn more about avian influenza in dairy cattle.   *The Occupational Safety and Health Administration is accepting comments on the proposed heat illness standard.   *U.S. beef exports were higher in July.  *Pasture management is making a difference on some Texas High Plains ranches.   *Congress is back in Washington D.C. and farm groups are pushing for action on a Farm Bill.   *The West Texas Fair and Rodeo in Abeline is attracting competitors and visitors from around the country.   *Coastal Bend farmers and ranchers are looking forward to better weather this month.   *This is the time of year to be concerned about salt toxicity in livestock.