[1
]International Organization Affairs, Foreign Agricultural Service, U.S. Department
of Agriculture, Washington, D.C. 20250
[2
]Department of Agronomy-Bioclimatology, Purdue University, West Lafayette, Indiana
47907
[3
]Cooperative State Research Service, U.S. Department of Agriculture
[4
]Department of Dairy Husbandry, University of Missouri-Columbia, Columbia, Missouri
65201
[5
]Board of Trustees, International Livestock Center for Africa
[6
]South Central Poultry Research Laboratory, U.S. Department of Agriculture, ARS, Mississippi
State, Mississippi 39762
[7
]U.S. Department of Agriculture, Beltsville, Maryland 20705
[8
]University of Alaska, Institute of Agricultural Sciences, Palmer, Alaska
[9
]Dept. of Biological Sciences, University of Nevada, Las Vegas 89154; and Laboratory
of Environmental Patho-Physiology, University of Nevada, Boulder City, Nevada 89005