Biting fly damage on bovine leather - An alternative source of 'light spot' damage

During the grading processes of leather, one of the most common downgrading defects is 'light spot'. Small scale trial work has established that a for m of 'light spot' was produced on bovine crust leather after the live anima l had been exposed to biting flies (specifically Stomoxys calcitrans). The resultant damage was found to have sharper boundary edges, compared wit h the diffuse edges associated with lice 'light spot' damage. The 'light sp ots' were grouped closely together and were of a more consistent, regular s ize and shape than either lice or demodex damage. The fly damage penetrated into the cerium layer of the skin, beyond the superficial grain enamel los s associated with lice damage.