I ISIll R^ mi I 1 1 IN: \ Ol . 7:. NO, I 



of post iiuMttMii rliaiiu'os uiuKm' \ arious comlilioiis 

 ■dw known. 



Tho pivsonl stuily was luuUMtakon 1o di'tiT- 

 n\\\w (lio normal rates ami patterns orpostnioi- 

 teni I'lianiie in penaei(i slirinip as an aid in ilis- 

 tinjiuishini;' gross and histologie elianges due 

 to aiitt>lysis 1V(mu ehanges liue to disease. 



MATHRIALS AND Ml- 1 HODS 



.luxiMiile blow 11 shrimp averaiiing "lO mm in 

 total lenjith (\'\\i of rc^strum to tip of ti'lsoii) 

 were obtained live iVom a eommereial bait ilealei" 

 and were held in 500-liter tiberu'lass tanks for 

 several ilays pritn* to beini; killed. Control 

 shrimp were killed by immersion in tixative. 

 Tlu^ remaininii' shrimp were killed by plaeiiii:' 

 the shrimp between wft towels in an enamel 

 tray for ;>0 min. The slirimji were removed 

 after oO min and plaeed \\\\o 100-ml glass jars. 

 Two groui>s at three temperatures (10'"\ 20 \ ami 

 SOT) were studied: one in air ami the other in 

 seawater. Shrim{) lield in air were introilueed 

 wet into test jars ami tiie jars were sealed. 

 Shrimp held in water were introdueed into the 

 test jars ami enough Instant Oeeaiv' artitieial 

 seawater (at .'U"t "'/(ut salinity') was atldeil to till 

 the jars. ,lars were heUl in wire baskets at 

 midlevel in eonstant temperature baths. 



Samples for antemortem examination were 

 taken at h while those for postmortem exam- 

 ination were taken at 2. 1. S. 12. 24. 48. and 72 

 h. Vouv eontrol shrimp were taken for study 

 and tw(i shrimp (one tVom seawater and one 

 from air) were taken from the 10 \ 20 \ and ;UV C" 

 baths at eaeh of the remaining sampling times. 



General appearance, color, odor, aiul eomli- 

 tion of the hepatopanereas were noted at eaeh 

 sampling period. Tissues for microscopic 

 examination were preserved in lO^'c buffered 

 Formalin, prejiared for microscopy with stan- 

 dard paraftin embedding and sectioning 

 methods, anil stained with liematoxylin ami 

 eosin. 



RKSl LTS 



Gross Observ ations 



The tirst change observed w as the onset of a 

 rigorlike condition of the abdomen which 

 appeared at about 2 h after tieath at oO 'C and at 



I \ni I 1. liiiu- ot oiiMl ol .1 I igDi like sliUcnini; o{ 

 shninp .iIhIihuiiuiI mustulaiuii' ,il 1(V\ 20'\ aiui 30'\' in 

 an and seawater. 



-I- = stiff 

 — = flaccid 



t and 2 1 h at 20 and \0'\\ respectively. Tlie 

 abdomen became flaccid at 12 and 48 h after 

 tleath in shiimi^ held at SO'^ and 20^X". but at 

 lO'T the abdomen remained rigid at 72 h after 

 death (Table 1). 



C'olor change ami the api)earance of spoilage 

 odor were tirst observed at 4 h after death at 

 oOH\ The general appearance of the shrimp 

 changed from the usual semitransparent to a 

 wliitish-opaque at about the same time the first 

 trace of odor was detected (Tables 2 and o). At 

 20 ' ami lO'X' the first color change and appear- 

 ance of odor were notetl at 12 h and 24 li. 

 respectively. At all three temperatures tlie color 

 of the shrimp changed from opaque to an orange- 

 red and finally to red with some blackened 

 areas (Table 2). The intensity of spoilage odor 

 increased along with the color change (Tables 2 

 and a). 



Fluid leakage from the hepatopanereas was 

 tirst observed at 4 h at oO'T and at about 8 and 

 12 h postmortem at 20' and 10 T. Enzymatic 

 cligestion of hepatopanereas and surrounding- 

 tissues was grossly eviilent at 12 h at oOT as 



1 AHi E 2. — Times lit' posUiioi tciii color chaniic of whole 

 shrimp at 10'\ 20'\ and 3lVX" in .m .uid se.iw.iiei. 



Temperoture C'C) 



H postmortem 



10-^C 



20 ^X 



30 -X 



Air Water 



Water Air Water 





 2 



4 

 8 



12 

 24 

 48 



' Rctcrcncc to trade names in liiis pul-ihcalion does not 

 imply endorsement of commercial product. 



— = normol 



= opaque 



LR = orange to light red 



R = red 



Rb = red with blackened edges of cuticle or blackened appendages 



224 



