Implications of chemosensory feeding in catfishes: an analysis of the diets of Ictalurus nebulosus and I. natalis

1985 ◽  
Vol 63 (3) ◽  
pp. 590-602 ◽  
Author(s):  
Allen Keast
Keyword(s):  
Young Adults ◽  
Food Availability ◽  
Fish Species ◽  
Metabolic Efficiency ◽  
Potential Prey ◽  
Brown Bullhead ◽  
Chironomid Larvae ◽  
Age Class ◽  
Ictalurus Nebulosus ◽  
Lower Standard

The implications of chemosensory feeding and associated ictalurid morphology were investigated through a seasonal study of the diets of the brown bullhead (Ictalurus nebulosus) and yellow bullhead (I. natalis) relative to food availability. Based on the attributes of chemosensory feeding (little discrimination between prey types) and bullhead morphology (poor sight, broad mouth), it was predicted that bullheads would be food generalists and opportunists, and that age-class diets would overlap. These predictions were generally supported for the brown bullhead. Some food types (amphipods) were harvested when most abundant; however, others (chironomid larvae) were consistently taken, and a few potential prey types were underutilized. The yellow bullhead, by contrast, was a food generalist only when young. Adults were specialized piscivores and crayfish feeders. The brown bullhead showed greater weight and length increases than co-occurring visually feeding centrarchids with diets of similar calorific values. Because of the similarity in calorific intake among species, a greater metabolic efficiency in brown bullheads was indicated. Other workers have shown that brown bullheads have lower standard and active metabolisms than some fish species.

Circadian rhythms in the brown bullhead, Ictalurus nebulosus (Teleostei). Evidence for an endogenous rhythm in feeding, locomotor, and reaction time behaviour

1980 ◽  
Vol 58 (10) ◽  
pp. 1899-1907 ◽  
Author(s):  
Lars-Ove Eriksson ◽  
Theo van Veen
Keyword(s):  
Reaction Time ◽  
Locomotor Activity ◽  
Feeding Activity ◽  
Brown Bullhead ◽  
Phase Angle Difference ◽  
Ictalurus Nebulosus ◽  
Angle Difference ◽  
Dark Regime ◽  
Free Running ◽  
Time Latency

Locomotor and feeding activity was investigated under(1) 12 h light(L): 12 h dark(D)and 16 h L: 8 h D, (2) 24 h D and 24 h L, and (3) dark pulses (0.75 h L: 0.25 h D), in the brown bullhead (Ictalurus nebulosus). In addition to locomotor and feeding activity, reaction time (latency time on lights-off and lights-on) was also measured.Fish subjected to a light–dark regime showed nocturnal behaviour, in many cases with a positive phase angle difference (i.e., the animals ceased their activity several hours before lights-on). Further, the actograms showed, as expected, a distinct 24 h rhythm. Only 2 brown bullheads out of 15, subjected to constant conditions, showed a circadian component in the locomotor activity, which could only be detected by frequency analysis.Nine out of 12 animals subjected to dark pulses (0.75 h L: 0.25 h D) showed a free-running circadian rhythm (approximately 23 h) in locomotor activity and 2 out of 3 showed such a rhythm in feeding activity. Observations and measurements of reaction time on leaving and re-entering the shelter after lights-off and lights-on (0.75 h L: 0.25 h D) showed also that this parameter has a circadian course. Measurements performed a fortnight later showed a similar, but less pronounced, pattern of behaviour.Dark pulses are thought to prevent rapid dissociation of a flexible multioscillatory circadian system in the brown bullhead.

Aggression of guarding male smallmouth bass (Micropterus dolomieui) towards potential brood predators near the nest

1993 ◽  
Vol 71 (2) ◽  
pp. 437-440 ◽  
Author(s):  
R. J. Ongarato ◽  
E. J. Snucins
Keyword(s):  
Aggressive Behaviour ◽  
Yellow Perch ◽  
Perca Flavescens ◽  
Smallmouth Bass ◽  
Brown Bullhead ◽  
Ictalurus Nebulosus ◽  
Defence Behaviour ◽  
Micropterus Dolomieui ◽  
Brood Guarding

Models of potential brood predators placed near the nest were used to elicit defence behaviour in male smallmouth bass (Micropterus dolomieui) in the field. The three predator models represented a conspecific, a species found in the lake (yellow perch, Perca flavescens), and a species not present in the lake (brown bullhead, Ictalurus nebulosus). Aggressive behaviour increased with brood age and with decreasing distance between model and nest. Brood-guarding smallmouth bass exhibited a generalized response to the three predator models and did not discriminate between them by altering levels of aggression.

Ictalurus nebulosus (Lesueur) (Brown bullhead) 2n = 60

1973 ◽  
pp. 17-19
Author(s):  
Maria Luiza Beçak ◽  
Willy Beçak ◽  
Franklin L. Roberts ◽  
Robert N. Shoffner ◽  
E. Peter Volpe
Keyword(s):  
Brown Bullhead ◽  
Ictalurus Nebulosus

scholarly journals Dietary patterns and home food availability during emerging adulthood: do they differ by living situation?

2009 ◽  
Vol 13 (2) ◽  
pp. 222-228 ◽  
Author(s):  
Melissa Nelson Laska ◽  
Nicole I Larson ◽  
Dianne Neumark-Sztainer ◽  
Mary Story
Keyword(s):  
Young Adults ◽  
Dietary Intake ◽  
Emerging Adults ◽  
Food Availability ◽  
Risk Groups ◽  
Dietary Factors ◽  
Apartment House ◽  
Living Situation ◽  
Home Food ◽  
Home Food Availability

AbstractObjectiveThe objective of the present work was to cross-sectionally examine and compare dietary behaviours and home food environments by young adults’ living situation.DesignUsing data from Project EAT (Eating Among Teens)-II, a large diverse youth cohort originally sampled in Minnesota, linear regression was used to examine self-reported meal frequency, dietary intake and home food availability outcomes by living situation (i.e. living with parents, renting an apartment/house or living on a college campus).SubjectsYoung adults (n 1687), mean age 20·5 years.ResultsResults suggested that young adults living with their parents or in rented apartments/houses had less frequent meals, poorer dietary intake and less healthy home food availability compared with those living on campus. These findings were evident even after controlling for sociodemographic factors (e.g. race/ethnicity, socio-economic status), particularly among females.ConclusionsAlthough few emerging adults consume diets that are consistent with national recommendations, those living with parents and in rented apartments/houses may represent particularly at-risk groups. These differences in dietary factors across living situations appear to exist beyond the sociodemographic differences in these populations. Effective nutrition and healthy eating promotion strategies are needed for young adults.

Fine structure of the axillary gland in the brown bullhead (Ictalurus nebulosus)

1991 ◽  
Vol 224 (4) ◽  
pp. 669-676 ◽  
Author(s):  
M. Whitear ◽  
G. Zaccone ◽  
S. Fasulo ◽  
A. Licata
Keyword(s):  
Fine Structure ◽  
Brown Bullhead ◽  
Ictalurus Nebulosus ◽  
Axillary Gland

scholarly journals Dermal Melanoma with Schwannoma-Like Differentiation in a Brown Bullhead Catfish (Ictalurus Nebulosus)

2002 ◽  
Vol 14 (3) ◽  
pp. 247-250 ◽  
Author(s):  
Kaori Sakamoto ◽  
M. Randall White
Keyword(s):  
Cell Junctions ◽  
Neurofilament Protein ◽  
Brown Bullhead ◽  
Cytoplasmic Staining ◽  
Color Changes ◽  
Ictalurus Nebulosus ◽  
Spindle Cells ◽  
Eosinophilic Cytoplasm ◽  
S 100 ◽  
Monomorphic Population

A dermal melanoma with histologic similarities to mammalian melanocytic schwannomas was diagnosed in a wild-caught brown bullhead catfish ( Ictalurus nebulosus). The diagnosis was based on cytologic, histopathologic, immunohistochemical, and ultrastructural findings. The neoplasm protruded from the cutaneous surface of the dorsal midline immediately caudal to the dorsal fin, was diffusely black and focally ulcerated, and was attached to the underlying skin by a broad-based stalk. Cytologically, the tumor was composed of a monomorphic population of melanophores, the melanin-producing and storing cells within the dermis and epidermis of fish that are partially responsible for rapid color changes. Histopathologic examination of the neoplasm revealed an unencapsulated, well-circumscribed, moderately cellular neoplasm composed of 2 distinct cell populations: spindle cells arranged in a “herringbone” pattern and numerous melanophores. The spindle cells had scant bipolar eosinophilic cytoplasm, with small centrally located vesicular nuclei; nucleoli were not seen. The histologic appearance was similar to that described for mammalian melanocytic schwannomas. Immunohistochemically, the spindle cells exhibited positive cytoplasmic staining for S-100 protein but were negative for vimentin, neurofilament protein, and glial fibrillary acidic protein. Ultrastructurally, the tumor consisted of neoplastic spindle cells with rudimentary cell junctions, actin bundles, and few melanosomes and melanophores with abundant intracytoplasmic melanosomes.

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