Effects on growth, survival, body composition, processing traits and water quality when feeding a diet without vitamin and mineral supplements to Australian red claw crayfish (Cherax quadricarinatus) grown in ponds

Abstract

To be profitable, producers must reduce diet costs, which can be as high as 80% of the variable costs of an aquaculture expense. As vitamin and mineral premixes represent a significant cost, eliminating addition of these premixes could reduce diet costs if no adverse effects were observed for growth and production parameters. A 105-day feeding trial was conducted with juvenile Australian red claw crayfish (Cherax quadricarinatus) to evaluate the effects of growth, survival, body composition, processing traits and water quality when red claw were fed a supplemental diet containing 28% crude protein (CP) without vitamin and mineral premixes (and supplemented alfalfa hay) compared with red claw fed a diet (control diet) containing 42% CP, vitamin and mineral premixes, and with supplemented alfalfa hay, and compared with red claw only fed alfalfa hay when grown in ponds. Juvenile red claw (mean weight of 15.7 AE 1.0 g) were randomly stocked into nine 0.02-ha ponds at a rate of 640 per pond (3.2 per m 2 ), and each treatment was used in three ponds. There were two feedings per day, each consisting of one-half of the total daily ration. At harvest, individual weight, percentage weight gain, specific growth rate, survival and total yield of red claw fed a control diet was significantly higher (P < 0.05) (83.0 g, 398%, 1.53% day À1 , 65.1%,and 1708 kg ha À1 respectively) compared with red claw only fed alfalfa hay (44.9 g, 202%, 1.04% day À1 , 30.3% and 431 kg ha À1 , respectively), but not different (P > 0.05) from red claw fed the supplemental diet without vitamin and mineral premixes (76.2 g, 367%, 1.47% day À1 , 57.2% and 1378 kg ha À1 ). There were no significant differences (P > 0.05) in feed conversion ratio (FCR) among treatments, which averaged 5.0 (based on prepared diet input). These results indicate that vitamin and mineral supplementation in a diet is not necessary when diet containing 28% CP and alfalfa hay are used in combination for pond grown red claw. These results may help reduce diet costs and possibly increase producers' profits which might allow for industry expansion.

Stochastic analysis of production dynamics of male and female redclaw crayfish (Cherax quadricarinatus) reared under commercial intensive cultivation

“…() and Kobayashi et al . (). Considering the difference in cultivation conditions and management, comparison of yields that we obtained with those reported by these authors is not straightforward.…”

“…This led to a closer prediction of biomass. We reviewed pond conditions and yields reported by Jones and Ruscoe (2000), Salame and Rouse (2000), Jones and Ruscoe (2001), Thompson et al (2004), Webster et al (2004), Thompson et al (2005), Rodgers et al (2006), Thompson et al (2006), Metts et al (2007), Saoud et al (2013) and Kobayashi et al (2015). Considering the difference in cultivation conditions and management, comparison of yields that we obtained with those reported by these authors is not straightforward.…”

Evaluation of Four Practical Diets on the Growth and Survival of Juvenile Redclaw, Cherax quadricarinatus (von Martens, 1868)

“…An experimental compound diet formulated by CSIRO (RC-16-2) was the second diet chosen for the experiment. Its formulation was based on a review of redclaw nutrition literature and designed specifically for early stage juvenile redclaw (Pavasovic 2008;Kobayashi et al 2015;Pirozzi et al 2016), and prepared as an extruded diet in crumble form (300 to 500 µm). For the third and fourth diet treatments, two whole organism foods were chosen on the basis that such food had proved successful in other redclaw studies (Jones 1995b;Parnes and Sagi 2002).…”