<script type="text/javascript">
        $(document).ready(function () {
            setInterval(function () {
                $("#top").fadeOut(function () {
                    $(this).attr("src", "https://www.r10.net/avatars/57819.gif?dateline=1359841323").fadeIn().delay(1000).fadeOut(function () {
                        $(this).attr('src', 'https://www.r10.net/avatars/61474.gif?dateline=1380197474').fadeIn().delay(1000);
                    });
                }
                );
            }, 4000);
        });
    </script>

<img id="top" src="https://www.r10.net/avatars/57819.gif?dateline=1359841323" width="60" height="60" />