Autoimmune haemolytic anaemia appears on the Cocker's health list, and while it is far less common than ear disease it is the entry most likely to be life-threatening.
In this condition the immune system attacks the dog's own red blood cells and destroys them faster than the bone marrow can replace them. The Cocker Spaniel is among the breeds recognised as predisposed. It can arise without any identifiable trigger, and it can develop over days.
The signs are worth committing to memory because they are easy to attribute to something else. Pale gums are the most useful — lift the lip and look, and compare it with what normal looks like on a healthy day. Beyond that: sudden lethargy or collapse, rapid breathing, a racing heart, reluctance to exercise, sometimes yellowing of the gums or the whites of the eyes, and dark orange or brown urine.
A dog with pale gums and sudden weakness is an emergency, not a next-morning appointment. Treatment involves immunosuppressive medication and sometimes transfusion, and outcomes are considerably better when it is caught early.
The rest of the Cocker's list is more routine: cataracts, progressive retinal atrophy — both picked up through eye certification, with DNA testing available for the retinal condition — and hip dysplasia.
The Pit Bull's list runs hip and elbow dysplasia, skin allergies, heart murmurs, bloat, obesity, cruciate ligament disease, arthritis and cancer. Its most likely orthopaedic emergency is a cruciate rupture, which is painful, surgical and strongly weight-linked.
For both breeds the single best free habit is keeping the dog lean, and for both, insuring before anything is diagnosed is what keeps a chronic condition affordable.