The fourth group consisted of crawfish harvested the previous day and purged for 24 hours in an aerated vat without access to feed.A subset of crawfish from each treatment on each test date was randomly collected for determination of hindgut content weight.
The amount of hindgut content in crawfish was greatest among the nonwashed specimens.
Regardless of whether gut contents were expressed as a percentage of whole wet crawfish weight (0.07 percent) or as dry abdominal weight (1.9 percent), the relative hindgut content weight of fully purged crawfish was significantly lower, approximately 60 percent less than that of crawfish not washed (Figure 4).
A similar portion of crawfish was placed in a second tub containing 10 gallons of water and 1.6 pounds of noniodized table salt and allowed to soak for 10 minutes (Figure 2).
A third portion of the day’s harvest consisted of nonwashed individuals.
This practice is based largely on hearsay or tradition, often passed down from generations.
Though seldom employed, commercial depuration, or purging, confines freshly harvested crawfish in water for one or two days without food prior to further sales.
Dedicated cooking rigs are used, often large enough to accommodate a 30- to 40-pound sack of crawfish – the typical means of transport.
Cooks will often empty the entire sack of crawfish into the pot, perhaps after a cursory wash.
The remaining crawfish from each wash treatment were sacked and immediately placed in humid refrigerated storage at 42-46 degrees Fahrenheit for assessment of mortality after 72 hours, a second objective of the study.