I really want to thank you for a wonderfully informative and supportive site. Our 2 year old female guinea developed a couple of mammary lumps but was otherwise well. We trust our vet who recommended removal but were incredibly anxious nonetheless. Your site gave me courage to go through with it and the information I needed to deal with all that the surgery and aftercare would entail. Her lumps were removed last Friday and she is recovering well. Interestingly her wounds are sealed with subcutaneous dissolvable stitches and superglue so there is nothing to bother her and they are incredibly neat. Today we are told they were lipomas. The lab has suggested they are usually caused by trauma which is a puzzle to us as our guineas are treated and handled very carefully. However, I am once again reassured by the suggestion on your site that these lipomas are most probably hereditary and so hopefully not caused by anything we have done. Thank you.