Discussion by
DAVID W. HILL, Research Sanitary Engineer
THOMAS N. SARGENT, Research Sanitary Engineer
JERRY L. DAUSE, Research Sanitary Engineer
U. S. Department of the Interior
Federal Water Pollution Control Administration
Southeast Water Laboratory
Athens, Georgia
The Federal Water Pollution Control Administration has assigned responsibility
for water pollution control research dealing with poultry processing wastes to the
Treatment and Control Research Activity at the Southeast Water Laboratory in
Athens, Georgia. This group worked closely with C. C. Griffith in the early stages of
his preparation of the subject paper and has helped promote recent research in
poultry processing waste treatment. C. C. Griffith are to be commended for their
effort in preparing the presented correlation from the scarce data available. Perhaps
the most important point in this presentation is that available data on poultry processing wastes in the published literature are extremely limited and out of date. For
example, it was necessary for Griffith to rely on a 1950 article by Ralph Porges and a
1958 paper by John Bolton in order to obtain data relating the strength of poultry
processing wastes to the live weight of birds. Although additional data on poultry
processing wastes are beginning to appear in the published literature, the amount of
such data is small compared to that which might be made available from private files
throughout the poultry processing industry. Individuals who have access to current
and significant data in this area should be encouraged to make these data accessible
to others in the field through the published literature.
The poultry processing industry is growing rapidly and undergoing significant
changes. The average obsolescence of poultry processing equipment is about two to
three years (1). The author has made an excellent attempt to extract some valuable
meaning from available data; but additional and more recent data of this nature,
based on a larger variety of live weights of chickens, should be examined either to
substantiate or to change the results the author presents.
The author's main conclusion is that the waste produced per one thousand lb
of live weight of birds processed increases greatly as the live weight per bird increases.
This significant relationship of the live weight per bird to the waste produced per
thousand lb of birds is not readily apparent until the very expanded nature of the
horizontal scale of the correlation is taken into account. The author's conclusion
stated in another way is that the percentage of degradable material in a bird that is
lost in processing to the waste treatment plant increases substantially with the size of
the birds. Unfortunately, there is not a wide variety of data based on significantly
different weights of chickens to thoroughly test this conclusion, but the need for such
■725