Can anyone locate the errors?

The following code contain some errors which im unable to locate. The problem is.....Im doing search and update. Im able to search the database and update Animal_Type and Animal_Breed BUT cannot update Premium_Habitat and Age......

Can some one locate that fatal error please

Thanks

<?php
	include("svrconfig.php");	
	$svr_connect = mysql_connect("localhost","root","magicpass");
	
	if(!$svr_connect)
	{
		die("Could not connect to server: ". mysql_error());
	}
	else
	{
		echo "Connected to server...<br/>";
		$db_connect = mysql_select_db("test_update", $svr_connect);
		
		if(!$db_connect)
		{
			die("Could not locate table: ". mysql_error());
		}
		else
		{
			echo "Connected to table: \"$table\"<br/><br/>";
		}
	}
	
	if(!isset($pet_code))
	{
		echo "Opps! No match found!<br/>";
	}
	
	$pet_code = $_POST['Pet_Code'];
	
	if(isset($pet_code) && $pet_code != '')
	{
		echo "You are UPDATING $pet_code.<br/>";
	}
	else
	{
		echo"No PET CODE entered...<br/>";
		die("<a href = \"pet_search.php\"> <strong>GO BACK</strong>");
	}
	
	//write search query
		
	$search = "SELECT * FROM $table WHERE Pet_Code = '$pet_code'";
	$result = mysql_query($search);
	$num = mysql_num_rows($result);
	
	mysql_close($svr_connect);
//--------------------------------------------------------------------------------------------------------------------------------------------//
	$i = 0;
	
	while($i < $num)
	{
		$pet_code = mysql_result($result,$i,"Pet_Code");
		$a_type = mysql_result($result,$i,"Animal_Type");
		$a_breed = mysql_result($result,$i,"Animal_Breed");
		$p_habitat = mysql_result($result,$i,"Premium_Habitat");
		$a_age = mysql_result($result,$i,"Age");
		
		echo "<form action = 'update.php' method = 'post'>
		<h3> $pet_code </h3>
		<input type='hidden' name='Pet_Code' value='$pet_code'>
		Animal Type: <br/> <input type = 'text' maxlength = '20' name = 'ud_a_type' value = '$a_type'><br/><br/>
		Animal Breed: <br/><input type = 'text' maxlength = '30' name = 'ud_a_breed' value = '$a_breed'><br/><br/>
		Premium Habitat: <br/><input type = 'text' maxlength = '30' name = 'ud_p_habitat' value = '$p_habitat'><br/><br/>
		Animal Age <input type = 'text' name = 'ud_age' value = '$a_age' >
		<input type = 'submit' value = 'UPDATE PETS'></forms>";
		$i++;
	}
	
	
	
	@$ud_a_type = $_POST['ud_a_type'];	
	@$ud_a_breed = $_POST['ud_a_breed'];
	@$ud_p_habitat = $_POST['ud_b_habitat'];
	@$ud_age = $_POST['ud_age'];
	
	include("svrconfig.php");	
	$svr_connect = mysql_connect("localhost","root","magicpass");// I assigned my password
	$db_connect = mysql_select_db("test_update", $svr_connect);
	$update_query = "UPDATE pets SET Animal_Type = '$ud_a_type', Animal_Breed = '$ud_a_breed', Premium_Habitat = '$ud_p_habitat', Age = 'ud_age' WHERE Pet_Code = '$pet_code'";
	mysql_query($update_query);
	mysql_close($svr_connect);
?>