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Juvenile red claw, Cherax quadricarinatus, were obtained from a commercial supplier and stocked into twelve 0.04‐ha ponds with an average water depth of approximately 1.1 m at a rate of 1100 red claw per pond (27,170 red claw/ha). Mean stocking weight (±SD) was 6.25 ± 3.0 g. Three replicate ponds were randomly assigned to each of the four treatments. In Treatment 1 (TRT1), red claw were stocked into ponds to which dried alfalfa hay (forage) was added at a rate of 500 kg/ha/mo; Treatment 2 (TRT2) consisted of red claw being fed a prepared diet containing 13% protein; in Treatment 3 (TRT3), red claw were fed a diet containing 13% protein at which had dried alfalfa hay been added at a rate of 500 kg/ha/mo; and in Treatment 4 (TRT4; control), red claw were fed a complete diet containing 28% protein. Water quality measurements were made three times weekly for dissolved oxygen and temperature (am, pm), pH, total ammonia nitrogen, nitrite, and alkalinity averaging 7.17 mg/L, 8.96 mg/L, 25.5 C, 27.3 C, 8.68, 0.39 mg/L, 0.012 mg/L, and 106.5 mg/L, respectively. After 113 d, the final mean weight of red claw fed TRT3 was significantly (P < 0.05) higher (68.10 g) compared to that of red claw fed hay only (49.40 g) but not different from red claw fed TRT2 (56.03 g) and TRT4 (62.10 g). Likewise, red claw fed TRT3 had significantly higher percent weight gain (990%) compared to that of red claw fed hay only (690%) but not different from TRT2 (796%) and TRT4 (893%). Feed conversion ratio of TRT2, TRT3, and TRT4 and percent survival among all treatments did not differ significantly (P > 0.05), averaging 2.85 and 66.8%, respectively. Total yield of red claw fed TRT3 and TRT4 (968 and 952 kg/ha) was significantly (P < 0.05) higher compared to that of red claw fed hay only (617 kg/ha) but did not differ from red claw fed TRT2 (882 kg/ha). Tail meat yield of male red claw in TRT3 was significantly (P < 0.05) higher (17.3 g) compared to that of male red claw in TRT1 (12.7 g) and TRT2 (14.9 g) but not significantly different (P > 0.05) from male red claw in TRT4 (16.9 g). Tail meat yield of female red claw in TRT3 and TRT4 was significantly (P < 0.05) higher (14.2 and 13.9 g, respectively) compared to that of female red claw in TRT1 (10.5 g) and TRT2 (10.4 g). Tail muscle proximate compositions showed no significant differences (P > 0.05) in protein (wet weight basis) between males and females among treatments (diet) which averaged 16.2 and 14.6%; however, there were little to no significant differences in fat and ash between males and females among treatments. Results from this study indicate that pond‐cultured red claw stocked at 27,170 red claw/ha can be fed a practical diet containing 13% protein, with or without forage (alfalfa hay), compared to red claw fed a complete diet containing 28% protein; however, if alfalfa hay is added to the pond at 500 kg/ha/mo as the sole source of added nutrients, growth is reduced. Therefore, the use of alfalfa hay, in combination with a low‐protein pelleted diet may be a production metho...

In this study, electrospun poly(vinyl alcohol) (PVA) microfibre mats incorporated with clove oil (CO) with high water-stability and water absorption ability were prepared through a heat-induced in situ cross-linkage with citric acid (CA). The effects of CA content on the electrospinning solution properties and physical properties of the crosslinked microfibre mats were investigated. The Fourier transform infrared spectroscopy showed that the esterification could occur between hydroxyl groups on the PVA and carboxyl groups on citric acid. The established strong interactions of citric acid and PVA after crosslinking improved the thermal stability, mechanical properties, contact angle, and water stability. The bacterial growth kinetics and the disk diffusion assay proved that the PVA/CA/CO microfibre mats had an obvious inhibitory effect on E. coli and S. aureus. The results showed the PVA/CA/CO microfibre mats would be a promising package material for food products.

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Shell-on tails of male (M), nonspawning female (F), and spawning female (SF) Australian red claw crayfish (Cherax quadricarinatus) (n = 270) were aerobically stored at 2• C up to 10 d to monitor meat quality changes under a retail condition. Percentage protein of SF muscle was higher (P < 0.05) and moisture and ash content lower (P < 0.05) than those of M and F muscles. The pH of muscle changed during storage, with SF generally having a lower value than M or F (P < 0.05). Lipid oxidation increased during the 1st 5 d and no significant difference existed between the 3 muscle groups. Cooking yield of SF (91.72%) at 10 d was significantly lower than that of M (96.25%) or F (97.81%), and its muscle shear force was also higher (P < 0.05) than M at 0, 3, 5, and 7 d and than F at 5 and 7 d. Sensory panel results (cooked meat tenderness, juiciness) were significantly correlated with instrumental results (shear force, cooking yield), with SF showing a lower meat tenderness, juiciness, and overall acceptability than M and F samples.

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