Are pigs dirty animals? The hide of cattle presented for slaughter can, at times, be excessively dirty due to adherent dirt, faeces and straw. Hide cleanliness can be improved in a number of ways such as controlling diet and feeding before slaughter, optimising housing conditions so that there is minimal soiling of the hide,

and transporting the animals to the abattoir under suitable conditions. Animals may also be clipped prior to slaughter to remove physical soiling, though this procedure can be dangerous for operatives and it is essential that it is undertaken using the correct handling facilities. The presentation of dirty cattle for slaughter is expensive for the farmer and the beef industry. Animals rejected for slaughter due to excessive levels of dirt may be returned to the farm of origin resulting in increased transport costs. Alternatively, animals may be clipped in the abattoir, or slaughtered at the end of the day. This will result in increased expenses due to additional lairage costs, bedding, labour etc. Dirty hides are also less valuable than clean hides.

Carcasses contaminated by excessively dirty hides will require additional trimming thus reducing carcass weights.

Why did it matter that dirty water polluted the river?
Can you think of a reason after looking again at the map? Be sure to write down your answers!