I work on a farm and recently noticed that a 13 year old doe's udder has swollen up. I milked her to see what would come out and a yellow liquid with spots of blood and chunks of white came out. Her udder was also very warm so I'm worried that it's infected. Large amounts of the yellow liquid came out. I tested the liquid for mastitis and the test came back negative. What could it be? There's a picture of the liquid attached. Oh, and the doe also seems to be losing weight.