Four practical diets containing 2% of crude protein (CP) (180 and 280 g kg−1), with or without menhaden fish meal (FM), were fed to Australian red claw Cherax quadricarinatus during a 97‐day feeding trial. Growth, survival, body composition and processing traits of pond‐cultured red claw were determined. Juvenile red claw (mean individual weight of 5.75 ± 3.3 g) were randomly stocked into twelve 0.04‐ha ponds at a rate of 1000 per pond (25 000 ha−1), and each diet was fed to three ponds. At harvest, the final mean weight of red claw fed Diet 4 (0 g kg−1 FM and 280 g kg−1 CP) and Diet 3 (113 g kg−1 FM and 280 g kg−1 CP) was significantly (P < 0.05) higher (62.4 and 58.5 g, respectively) than red claw fed Diet 1 (73 g kg−1 FM and 180 g kg−1 CP; 51.7 g) and Diet 2 (0 g kg−1 FM and 180 g kg−1 CP; 53.0 g). Red claw fed diets containing 280 g kg−1 CP, with or without FM, had significantly higher percent weight gain (894 and 959%, respectively) compared to red claw fed 180 g kg−1 CP, with or without FM (778 and 799%, respectively). Feed conversion ratio, percent survival, and total yield among treatments, which averaged 3.55, 65.2%, and 724 kg ha−1 overall, were not significantly different. Results from this study indicate that pond‐cultured red claw stocked at 25 000 ha−1 can be fed a practical diet containing 280 g kg−1 CP with 0 g kg−1 FM if a combination of plant‐protein ingredients (soybean meal, distillers’ dried grains with solubles, and milo) is added; however, if the percentage of dietary protein level is 180 g kg−1, growth is reduced even if FM is added at 73 g kg−1 of the diet. Use of diets containing plant‐protein sources may help reduce diet costs to producers and thereby, increase profits.

The freshwater prawn Macrobrachiurn rosenbergii is a commercially important culture species in the South Central United States. Two major constraints in the commercial culture of the freshwater prawn in the U.S. are poor survival during live transportation of seed-stock to growout ponds, and live transportation of pond harvested prawn to distant live markets due to the territorial and cannibalistic nature of prawn. The use of anesthetics could possibly improve transport survival; however, to date anesthetic agents have not been evaluated for use with prawn. Two trials were conducted with juvenile freshwater prawn to compare the efficacy of anesthetics commonly used on fish. The first trial was designed to identify the most promising candidates. In Study 1, tricaine methanesulfonate (MS-222), 2-phenoxyethanol, quinaldine sulfate (quinaldine), clove oil, and Aqui-STM were evaluated at 25 and 100 mg/L for 1 h in three replicate 10-L glass containers, containing five juvenile prawn each. Relative sedation level was determined every 3 min for 1 h, then recovery time and survival were measured. In Study 1, MS-222 and 2-phenoxyethanol were determined to be ineffective on prawn at all rates tested. Based on their performance in Study 1, quinaldine, clove oil, and AquiSTM were evaluated at 100, 200, and 300 m f i in Study 2. Observations were determined as in Study 1. Clove oil and AquiS" induced anesthesia faster and at lower concentrations than quinaldine. At the highest treatment rate (300 m e ) prawn suffered 60% mortality in the Aqui-S" treatment, 13% mortality in the quinaldine treatment, and 0% mortality in the clove oil treatment and control following a 1-h exposure to these concentrations. Based on these data, AquiS" and clove oil applied at 100 mg/L may be suitable anesthetic treatments for prawn. Additional research is needed to determine optimal time and dose relationships to minimize stress during holding, handling, and transportation of prawn. Zar, J. H. 1984. Biostatistical analysis, 2nd edition.

ABSTRACT. Juvenile (mean weight 8.1 g) Australian red claw crayfish, Cherax quadricarinatus, were stocked in July at three rates of 12,000/ha, 18,000/ha, and 24,000/ha into two, 0.02-ha earthen ponds in a cool temperature region of the United States (Kentucky) and grown for 70 days. Red claw were fed a pelleted marine shrimp diet twice daily. Ponds had continual aeration provided. Dissolved oxygen and temperature were measured twice daily (0900 and 1530 hours); total ammonia nitrogen (TAN), nitrite, and alkalinity were measured twice weekly; and pH was measured daily. At harvest, there were no significant (P > 0.05) differences in final individual weight, percentage weight gain, specific growth rate, feed conversion ratio, percentage survival, yield, and economic return among all treatments and averaged 58.4 g, 805%, 3.04%/ day, 7.47, 42.7%, 461 kg/ha, and Ϫ$2659/ha, respectively. There were no significant (P > 0.05) differences in the percentage of males and females harvested from the ponds among any stocking rate with males comprising 48.2% and females comprising 51.8%. Final individual weight of males and females was not significantly (P > 0.05) different among all treatments. These data indicate that there is no advantage to stocking red claw at rates below 24,000/ha in terms of growth, survival, yield, and economic return and that red claw can grow to marketable size in a cooler temperate region of the United States with a short (<110 days) growing season by stocking a larger-size (8 g) red claw.

Economical, nutritious diets for hybrid striped bass (HSTB) are required for the continued expansion and sustainability of this industry. Turkey meal (TM) is a by‐product of the US turkey industry and is a potentially‐valuable local, alternative protein source for use in aquaculture diets because of its excellent nutritional composition and quality. TM may substitute for more expensive fish meal (FM)‐based diets; however, there are no published data with regard to using this ingredient in sunshine bass diets. Therefore, a 16‐week feeding trial was conducted with juvenile (36 g) sunshine bass (Morone chrysops × Morone saxatilis) to evaluate growth, feed conversion and body composition when fed diets with decreasing levels of FM (300, 200, 100 and 0 g kg−1) and increasing levels of turkey meal (0, 97, 175 and 264 g kg−1). Four practical diets were formulated to contain 400 g kg−1 protein and similar energy levels. Twenty fish were stocked into each of the 12, 1200‐L circular tanks and were fed twice daily ad libitum. At the conclusion of the feeding trial, there were no significant (P > 0.05) differences in final mean weight, percentage weight gain, specific growth rate and feed conversion ratio among treatments, which averaged 363.7 g, 904.3%, 2.02% day−1 and 1.73, respectively. Percentage survival of fish fed diet 4 (0 g kg−1 FM and 264 g kg−1 TM) was significantly (P > 0.05) lower (survival = 88.3%) than fish fed diet 3 (100 g kg−1 FM and 175 g kg−1 TM; survival = 95%), but not different from fish fed diet 1 (survival = 92.5%) and fish fed diet 2 (survival = 93.3%). Fillet weight and amount of abdominal fat were not significantly different among all treatments and averaged 258 and 58 g kg−1, respectively. Fish fed diet 1 (300 g kg−1 FM, 0 g kg−1 TM) and diet 2 (200 g kg−1 FM and 970 g kg−1 TM) had a significantly (P < 0.05) lower hepatosomatic index (2.83 and 3.01, respectively) than fish fed diet 4 (3.33), but not different (P > 0.05) compared to fish fed diet 3 (3.14). Lipid in the fillet of fish fed diet 2 (197 g kg−1) was significantly (P < 0.05) higher than fish fed all other diets; and the percentage lipid in the fillet of fish fed diet 1 (126 g kg−1) was significantly lower than fish fed diets 2 and 4, but not different (P >0.05) compared to fish fed diet 3. Fillet moisture, protein and ash were similar among fish fed all diets and averaged 748, 798 g kg−1 and 51.0 g kg−1 (dry‐matter basis), respectively. The amino acid composition of fillets was similar among all treatments with a few slight significant differences. Results from the present study indicate that tank‐grown sunshine bass can be fed a diet containing 264 g kg−1 TM with 0 g kg−1 FM, compared to diets containing up to 300 g kg−1 FM, without adverse effects on weight gain, growth rate, feed conversion and body composition. Further research should be conducted using lower‐protein diets to determine minimum protein level for tank‐grown sunshine bass.

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