O<i> ur readers wrote letters throughout 1986 expressing their viewpoints on a variety of issues. Here are condensed versions of some of those letters. We appreciate their taking the time to share their viewpoints and look forward to hearing from you in 1987.</i>

Dr. Dan Hays appeared in The Times recently supporting the vital importance of vivisection in medical research.

I first met Dr. Hays on May 20, 1964, when I was 2 days old. He performed emergency surgery to reconstruct my esophagus. Without the operation I would have starved to death.

Medical techniques developed through animal research have saved millions of lives, including mine. With advances being made in the study of cancer, diabetes and heart disease, medical research holds the potential for saving millions more.

JOHN D. LIECHTY

Newport Beach