Production Characteristics, Water Quality, and Costs of Producing Channel Catfish <i>Ictalurus punctatus</i> at Different Stocking Densities in Single‐batch Production

Ruebush²,

Leyva³

et al. 2009

N American J Aquac

Pond studies were conducted in 2002 and 2003 to determine whether reduced growth from feeding channel catfish Ictalurus punctatus every other day in multiple‐batch systems could be overcome by offering feeds with a higher crude protein level. In the 2002 study, fish were fed a commercial diet containing either 28% or 36% crude protein every other day to apparent satiation. Survival, net yield, total yield, and weight at harvest of either fingerlings or carryover fish (second year of production; mean weight, 300 g) fed a 28% crude protein diet were not significantly different from those of fish fed the 36% crude protein diet. Fingerling growth was less than 1.0 g/d for both diets, while carryover fish reached market size with both diets when fed every other day. The study was expanded in 2003 to include a 32% protein treatment and control (fed daily). Fingerling growth, weight at harvest, and feed conversion ratio (FCR) were significantly lower when fingerlings were fed every other day than when the fish were fed daily. Higher protein levels did not improve survival, FCR, growth, weight at harvest, or net yield of fingerlings. Carryover fish in all treatments reached market size by the end of the study, but yield was lower when fish were fed every other day and was not affected by protein level. Partial budget analysis indicated a positive change in revenue the first year from switching from feeding every day to feeding every other day, but returns turned negative during the second year. Feeding every other day resulted in smaller fish, lower carryover biomass, and second‐year yields below the break‐even level. No evidence was found to support the use of higher‐protein diets when feeding every other day.

Section: Resultsmentioning

confidence: 99%

Section: Methodsmentioning

confidence: 99%

The Effect of Dietary Protein Level on Channel Catfish Production Characteristics when Feeding on Alternate Days in Multiple‐Batch Production

Ruebush²,

Leyva³

et al. 2009

N American J Aquac

“…Previous pond studies at the University of Arkansas at Pine Bluff (UAPB) have looked at a variety of single and multiple-batch characteristics of both fingerlings (6.7 cm-17.8 cm; Engle & Valderrama, 2001;Pomerleau & Engle, 2003;Pomerleau & Engle, 2005a, Pomerleau & Engle, 2005bSouthworth, Stone, & Engle, 2006a;Southworth, Stone, & Engle, 2006b) and stocker size catfish (55 g-361 g; Pomerleau & Engle, 2003;Green & Engle, 2004;Pomerleau & Engle, 2005a, b). A small stocker is a fish in the size range of 27 g-82 g and a large stocker is a fish in the size range of 82 g-340 g (USDA, 2006).…”

Section: Introductionmentioning

confidence: 99%

“…Feed was estimated for all densities with an assumed FCR of 1.75 based on a 2004 multiple-batch study done at UAPB (Southworth, Stone, & Engle, 2006b). Many single-batch studies (Busch, 1984;Pomerleau & Engle, 2003;Green & Engle, 2004;Southworth, Stone, & Engle, 2006a) and multiple-batch studies (Engle & Valderrama, 2001;Tucker et al, 1993;Southworth, Stone, & Engle, 2006b) conducted in the past have found no significant differences in FCR due to varying stocking densities, with conversion values ranging from 1.0 to 2.0. In the current study, sensitivity analyses were done by varying FCR from 1.0 to 2.0.…”

mentioning

confidence: 99%

The Effect of Understocking Density of Channel Catfish Stockers in Multiple-Batch Production

Southworth

Journal of Applied Aquaculture

Ruebush

2009

Self Cite

A multiple-batch study was conducted using stocker catfish (0.09 kg/fish) and carryover fish (0.39 kg/fish) to look at the effects of different stocker densities on fish production. Twelve 0.1-ha ponds were stocked with 7,400; 11,120; or 14,825 stockers/ha, and equal weights of carryover fish (2,268 kg/ha). Fish were fed once daily to apparent satiation with a 32% protein floating feed and aerated with a single 0.37-kW electric paddlewheel aerator. No significant differences were detected for gross, net, and net daily yields, growth (g/d), or survival. Sub-marketable yield (<0.57 kg) increased as stocking density increased. However, marketable yields (³0.57 kg) were not affected by density. Carryover fish in high-density ponds had a significantly lower (P < 0.05) mean weight at harvest, but mean stocker weight was not different across densities. Economic analysis found breakeven prices increased and net returns decreased with increased stocking density when sub-marketable fish were not considered as revenue. The study indicated the possibility that stockers compete with large carryover fish, particularly at higher densities.

“…Data for growth, survival, and yield in multiple-batch production of fingerlings and carryover fish were taken from Engle and Valderrama (2001), Engle et al (2009) and Nanninga and Engle (2010) for various feeding strategies (Tables 2 and 3). Performance of the three different stocker weight classes when fed with different feeding strategies was adopted from the performance of similar weight classes of stockers from Green and Engle (2004), Pomerleau and Engle (2005) and Southworth et al (2006) ( Table 4). The initial model used a feed price of $440=MT and a catfish price of $2.76=kg, with unlimited access to operating capital and labor.…”

Section: Optimizing Catfish Feeding and Stocking Strategies 173mentioning

confidence: 99%

Optimizing Catfish Feeding and Stocking Strategies Over a Two-Year Planning Horizon

Kumar

Aquaculture Economics & Management

2014

Self Cite

& Rising costs of feed ingredients in recent years have resulted in record increases in catfish feed prices. Since understocked channel catfish (Ictalurus punctatus) do not reach market size until the second year of production, static one-year economic models and analyses may not be adequate. A previous mixed-integer profit-maximizing model was extended to include a second year to evaluate the effects of varying feeding frequencies on farm management decisions, particularly on adjustments in the second year. Production options considered included frequency of feeding (every day, every other day, and every third day), multiple-batch production from four different fingerling sizes, and single-batch production from three different stocker sizes. Every day feeding was identified as the profit-maximizing feeding strategy on farms using multiple-batch production but unfavorable market prices, high feed prices, and operating capital constraints reduced feeding frequencies.Every day feeding remained the optimal strategy for farms in single-batch foodfish production. Market and capital constraints reduced the scale of farms operating in single-batch foodfish production, but did not change the optimal every day feeding strategy. Farms maximized profits by transitioning from multiple batch to single batch over the two-year period.