Submitted on: 27 March 2000.
Revised on: 11 May 2000.
Accepted on: 14 June 2000.
___________________International Journal of Veterinary Science and Medicine
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Submitted on: 13 May 2008.
Revised on: 26 July 2008.
Accepted on: 17 August 2008.
___________________International Journal of Veterinary Science and Medicine
Submitted on: 16 June 2007.
Revised on: 26 July 2007.
Accepted on: 02 September 2007.
___________________International Journal of Veterinary Science and Medicine
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