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I would build on Terry's suggestion too, by looking for dental malocclusion as a cause, especially a "wave mouth" pattern where the cheek teeth near the center of the arcade are high and those on one or both ends low. This pattern of tooth development, eruption and wear alters the pressure profile as measured from anteriormost premolar back along the jaws to the jaw joint so as to shift pressure to the jaw joint. This in turn may not only cause the condyle and/or glenoid to develop abnormally, but will maintain or increase abnormality even after the animal becomes skeletally mature. On this same topic, one thing I'd like to hear report of is the incidence in cattle of some of the general types of lesions we see in humans, i.e., where the meniscus of the jaw joint becomes inflamed and then adheres either to the top of the condyle or to the concavity of the glenoid, or sometimes breaks in half with half sticking above and the other half below. I've seen this only once in horses, and in that case, the animal had system-wide abnormalities in bone development. In general, jaw joint lesions of any type are rare in horses, though I've seen the sort of "waisted" condyle in horses that I think you're describing for cattle. As Sue S. and others in this thread mentioned, the fact that you seem to have a lot of examples from a single site is probably significant. -- Deb Bennett > Hi Emily, > I have seen clefts, pits and shallow craters in cattle mandible condyles > now and then. They appear to be the same thing that we see on limb > articular surfaces, i.e. osteochondroses resulting from a localised > failure of growing subchondral bone to mineralise. If you have a cluster > of cases, I would suspect that reflects diet and grazing conditions (and > hence stress on the temporomandibular joint in young animals) rather than > genetics. Unless, that is, there was some congenital predisposition in > this population. Thanks for bringing this up. Joint lesions are > fascinating! > Terry > > > > > > Sent from my Samsung Galaxy smartphone.-------- Original message > --------From: Emily Murray <[log in to unmask]> Date: 09/01/2018 > 10:54 (GMT+00:00) To: [log in to unmask] Subject: [ZOOARCH] Cleft in > cattle mandibular condlye > Baker and Brothwell (1980, 112-4) in their book 'Animal Diseases in > Archaeology' suggest that clefts/grooves in mandibular condyles of cattle > and sheep, along with minor pitting, are considered 'minor, > non-pathological variation from the normal'. Is this still the accepted > interpretation? I have recorded quite a few examples on a site in Ireland > and would be interested to know if there has been any further work done on > this. > Thanks,Emily >