<Canvas xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
	xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">

        <Canvas Canvas.Left="83" Canvas.Top="135" Width="200" Height="200" Background="Green">
		<Ellipse x:Name="ellipse" Stroke="red" StrokeThickness="1" Width="300" Height="150" RenderTransformOrigin="0.5,0.5">

			<Ellipse.Triggers>
				<EventTrigger RoutedEvent="Ellipse.Loaded">
				  	<BeginStoryboard>
				    	<Storyboard x:Name="animation">
				      	<DoubleAnimation
				        	Storyboard.TargetName="ellipse"
				        	Storyboard.TargetProperty="StrokeThickness"
				        	To="10" Duration="0:0:3"
						AutoReverse="True" RepeatBehavior="Forever" />
				    	</Storyboard>
				  	</BeginStoryboard>
				</EventTrigger>
			</Ellipse.Triggers>
		</Ellipse>
	</Canvas>
</Canvas>
