Slowly count the number of records in a table

Use the JavaScript setInterval () :

var contador = document.getElementById('contador');
var TOTAL_CLIENTES = 10;

var intervalo = setInterval(function() {
  contador.innerHTML = parseInt(contador.innerHTML, 10) + 1;

  if (contador.innerHTML == TOTAL_CLIENTES) {
    clearInterval(intervalo);
  }
}, 500);

<p>Clientes cadastrados: <span id="contador">0</span></p>

The above code will increment the value of <span> by 1 every 500 milliseconds. You can change the increment interval as you want, leave it faster or slower.

TOTAL_CLIENTES is your value from PHP:

var TOTAL_CLIENTES = <?php echo $admcadastros; ?>;

You can use a meta tag to refresh your page from time to time:

<meta http-equiv="refresh" content="5"> // 5 segundos

Or by AJAX, explained its working here:

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