The persistence to slaughter age of scars resulting from damage inflicted to ostrich skins during the grow-out phase

Damage to ostrich skins in the form of cuts and scratches obtained during the grow-out phase results in lower quality skins that fetch lower prices. This represents major financial losses to the ostrich industry. The stage at which such damage occurs and its persistence to slaughter age, when it affects skin grading, is not known. In this study we assessed the persistence through to slaughter age of wounds inflicted on the skins of ostrich chicks at ages 1, 4, 7, 10 and 13 months. Superficial and deep wounds were investigated by either scratching the skin with a nail, or by cutting through the skin with a scalpel blade. Experimental animals were slaughtered at either 11 or 14 months of age and visible scars were assessed on the processed skins. The length and surface area of each scar were measured to obtain an adjusted scar size. Orientation of lacerations (dorso-ventral or anterior-posterior) proved to be unimportant. Cut wounds were persistent to slaughter as were scratch marks, with only a small percentage of scratch wounds incurred at a young age not persisting to slaughter age. Mean scar size at slaughter became smaller with an increase in age at which the wounds were inflicted, except at 13 months of age where it was assumed that the wounds had not had sufficient time to heal properly. Deep cut wounds caused larger scars at slaughter age than superficial scratch damage. It seems that both superficial (scratches) and deep (cuts) wounds will result in lower skin grading, irrespective of age of infliction. This indicates that changes in chick rearing practices are necessary to reduce the incidence of skin damage if skin quality is to be improved.