Gif Animation is not working as expected in WPF - wpf

Question

I am having one multi thread WPF application. In that application am using gif image with one of the threads. I need to check whether database connection is established or not ,until then the icon should be loading gif, after that which will turn into success or failure icon accordingly.
I have used the following code to set the gif initially .
<Image x:Name="sample" Grid.Row="1" gif:ImageBehavior.AnimatedSource="{Binding DataBaseImageSource}" Margin="{Binding ElementName=BorderContainer, Path=Margin}" />
After that i am changing the icon using below code. This code will get executed after window.show() method.
try
{
myContext.Database.Connection.Open();
myContext.Database.Connection.Close();
this.DataBaseImageSource = (BitmapImage)Application.Current.FindResource("SuccessIcon");
}
catch (SqlException e)
{
this.ResultSummary = "Failure";
this.DataBaseSummary = e.Message.ToString();
this.DataBaseImageSource = (BitmapImage)Application.Current.FindResource("ErrorIcon");
return false;
}
return true;
once i called this above window.show() method, then am changing the animated source based on the database availability .
But the gif is not at all loading it behaves like a normal png image, after that the image gets changed based on the result. how can i make gif to be animated followed by source change?