K. Bondari

Selection responses were compared in 4 lines of channel catfish (lctalurus punctatus) selected for: (1) large 40-week body weight (W+), (2) large spawn weight (S+), (3) sma1l40-week body weight and large spawn weight (W-S+), and (4) large 40-week body weight and small spawn weight (W+S-). Each line comprised 4 spawns hatched into 4 sibling sets. Ten randomly selected fish from each sibling set (40 fish per line) were included in the study and were grown in 2 segments of a recirculating raceway system. Results indicated that single-trait selection for 40-week body weight was most effective...

First generation inbred channel catfIsh (Ictalurus punctaius) were produced from full brother-sister matings to be compared in growth response to various temperature regimes to a control family produced from the same base population. Temperature regimes involved: (1) constant 22 C well water for 28 weeks, (2) well water heated to 27 C for 20 weeks and not heated (22 C) for the subsequent 8 weeks, and (3) ambient temperature of a 2-ha reservoir. Results indicated that genetic divergence between 2 lines was associated with a differential response to temperature regime. Weekly weight gain and...

Abnormal characteristics studied were taillessness, triple-tailed, crookedback, albinism, and piebaldness in channel catfish (Ictalurus punctatus) and missing dorsal rm in blue tilapia (Tilapia aurea). Tailless catfish were divided into 2 groups: (1) totally tailless with the caudal rm completely missing and (2) partially tailless with the caudal rm reduced in size and modified in shape. Results indicated that the absence of the caudal rm in channel catfish severely reduced body weight and total length and should be selected against. Crooked back abnormality reduced body weight by 28 and...

Six groups of cage-grown channel catfish (lctalurus punctata) and Tilapia aurea were compared for body weight, total length, condition factor, carcass characteristics, and sensory quality. Catfish used in this study were the first generation progeny of brood catfish selected for increased and decreased body weight and for body weight variability at 48-week post-spawning age. A random-bred control line and a group of pond-raised catfish were also included in the experiment. Results indicated that I generation of divergent selection has increased body weight and body weight variability in...