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We compared performance (growth, survival, condition, and health indices) of largemouth bass, Micropterus salmoides, fin-gerlings (10.3 g fSE ± 0.5 gl and 92 mm [SE ± 1 mm] total length) fed one of four commercial grower feeds: Purina Aquamax Grower 400 (PAG; PMI Nutrition International LLC), Bio-Oregon BioDiet Grower (BDG; Bio-Oregon), Silver Cup Steelhead (SCS; Silver Cup), and Richloam Bass Fry Diet 12 (RBF; Silver Cup). Sixteen 833-L circular tanks, connected in parallel to a recirculation system, were initially stocked with 2.25 kg offish (219fish each, 0.32 fish ID with four replicates per feed treatment. Water temperature was 25° C, and photoperiod was 15 h light:9 h dark. Feed sizes (2.4-30 mm) were comparable, and protein compositions ranged from 49% to 61%. Fish were fed to satiation multiple times per day (trial duration = 100 days). Overall, performance was best for fish fed RBF, followed by PAG and BDG, and then SCS. The SCS feed resulted in significantly lower growth and survival (P ⩽ 0.05). The PAG and BDG feeds resulted in significantly lower growth than the RBF feed (P ⩽ 0.05); however, survival did not differ (P > 0.05). Performance measures were positively correlated with protein, and protein to energy ratio and negatively correlated with fat and carbohydrate compositions. The four commercial grower feeds resulted in highly varied growth, survival, and health indices, and this research should facilitate feed choice for various largemouth bass production strategies as well as increase contribution of stocked fish. [ABSTRACT FROM AUTHOR]

We compared performance (growth, survival, and condition) of northern largemouth bass Micropterus salmoides salmoides fingerlings fed one of three commercial starter feeds: Otohime Marine Weaning (OMW; Marubeni Nisshin Feed), Bio-Oregon BiVita Fry (BVF; Bio-Oregon), and Purina Aquamax Starter (PAS; PMI Nutrition International LLC). Nine 833-L circular tanks, connected in parallel to a recirculation system, were stocked with 465 fish (1.4 kg), each to provide a rearing density of 1.1 fish/L. Water temperature was maintained at 27°C, and photoperiod was 15:9 h light:dark. Feed sizes (1.5-1.6 mm) were comparable and had similar protein composition (48%-50%). Feed was dispensed by vibratory feeders at a rate of 5% BWPD from 0730 h to 2130 h every 0.5 h for a total of 29 feedings per day (trial duration = 22 days). Overall performance was best for fish fed OMW, followed by BVF, then PAS. The PAS feed resulted in significantly lower growth, survival, and condition factor (P ⩽ 0.05). Though not statistically significant, the BVF feed resulted in lower growth, condition factor, and survival than OMW (P > 0.05). Performance measures were positively correlated with crude fat and negatively correlated with protein to energy ratio of feeds. The OMW or BVF diets may be more appropriate for intensive culture when the artificial feed is the sole food supply, while the PAS diet may be more suitable for extensive culture as a supplemental food source. [ABSTRACT FROM AUTHOR]

The white bass (Morone chrysops) is an important sport fish species in the upper Midwest. As such, understanding white bass dynamics is critical for managing its populations. Thus, we evaluated population dynamics of white bass in a northwestern South Dakota reservoir and attempted to determine whether bass recruitment patterns were more related to reservoir inflows or spring weather patterns. We found that white bass growth increased from 243 mm for age-2 fish, to 322 mm for age-6 fish, and then to 346 mm at age 9. The total annual mortality rate was 29.7%. In terms of year-class strength, white bass recruitment was erratic. The recruitment pattern was more related to spring weather patterns than reservoir inflow. In comparison, white bass population dynamics in this South Dakota irrigation reservoir were more similar to those of white bass populations in Midwestern glacial lakes than those found in southern US reservoirs. [ABSTRACT FROM AUTHOR]