A practical method to prevent dark-cutting (DFD) in beef.
A method for the prevention of dark-cutting in beef, based on recognition of social relationships within groups of bulls, was tested on 2234 bulls slaughtered under commercial conditions. When the influence of time between loading the animals and slaughter was eliminated statistically, the bulls of the socially stablized group showed the lowest pH(24) values, whereas those of the socially unstable group showed the highest ones. When the type of social group was eliminated statistically, the earlier slaughtered animals had lower pH(24) values than those slaughtered later. When the two major factors were integrated, there was no statistically significant difference in the pH(24) values in bulls of the socially stabilized group whether they were slaughtered immediately after transport or during the following day. In contrast, in bulls from the socially unstable group, the pH(24) values increased substantially after overnight lairage at the abattoir. In conclusion, for longer transportion, bulls from loose housing with stable social relationships should be used. It is necessary to keep the same social groups from loading to slaughter, strictly avoiding any mixing of strange bulls. Bulls from tethered stalls should be transported and slaughtered within as short a time after regrouping as possible.