Effect of short-term feeding duration of diets containing commercial whole-cell yeast or yeast subcomponents on immune function and disease resistance in channel catfish, Ictalurus punctatus

Channel catfish (Ictalurus punctatus) fingerlings were fed semipurified diets containing 0–150 mg/kg of vitamin C for 14 wk and subsequently at two temperature regimes infected with the pathogenic bacterium Edwardsiella tarda. Mortality rates were determined 96 h after infection. A supplemental vitamin C level of 30 mg/kg of diet was sufficient for normal growth and for prevention of deficiency signs such as lordosis, scoliosis, and a reduction in bone collagen formation. However, increased resistance against infection was provided when the level of supplemental vitamin C was increased to the highest dietary level, 150 mg/kg, at a water temperature of 23 °C. At 33 °C, increasing the supplemental level of vitamin C had significantly less effect on resistance against infection. The difference in response at the two temperatures indicates that the vitamin C requirement for resistance to infection is possibly higher when channel catfish are infected at lower temperatures, where the natural resistance is reduced, than when infected at a temperature near optimum for the natural resistance mechanisms of the fish.Key words: vitamin C, channel catfish, disease resistance, Edwardsiella tarda, infection

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Tissue Distribution and Immunomodulation in Channel Catfish (Ictalurus punctatus) Following Dietary Exposure to Polychlorinated Biphenyl Aroclors and Food Deprivation

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17041228 ◽

2020 ◽

Vol 17 (4) ◽

pp. 1228

Author(s):

Shannon L. White ◽

Devin A. DeMario ◽

Luke R. Iwanowicz ◽

Vicki S. Blazer ◽

Tyler Wagner

Keyword(s):

Immune Response ◽

Immune Function ◽

Food Deprivation ◽

Ictalurus Punctatus ◽

Stress Responses ◽

Channel Catfish ◽

Polychlorinated Biphenyl ◽

Dietary Exposure ◽

Total Pcbs ◽

Whole Body

Although most countries banned manufacturing of polychlorinated biphenyls (PCBs) over 40 years ago, PCBs remain a global concern for wildlife and human health due to high bioaccumulation and biopersistance. PCB uptake mechanisms have been well studied in many taxa; however, less is known about depuration rates and how post-exposure diet can influence PCB concentrations and immune response in fish and wildlife populations. In a controlled laboratory environment, we investigated the influence of subchronic dietary exposure to two PCB Aroclors and food deprivation on tissue-specific concentrations of total PCBs and PCB homologs and innate immune function in channel catfish (Ictalurus punctatus). Overall, we found that the concentration of total PCBs and PCB homologs measured in whole body, fillet, and liver tissues declined more slowly in food-deprived fish, with slowest depuration observed in the liver. Additionally, fish that were exposed to PCBs had lower plasma cortisol concentrations, reduced phagocytic oxidative burst activity, and lower cytotoxic activity, suggesting that PCBs can influence stress and immune responses. However, for most measures of immune function, the effects of food deprivation had a larger effect on immune response than did PCB exposure. Taken together, these results suggest that short-term dietary exposure to PCBs can increase toxicity of consumable fish tissues for several weeks, and that PCB mixtures modulate immune and stress responses via multiple pathways. These results may inform development of human consumption advisories and can help predict and understand the influence of PCBs on fish health.

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Short term effects of limb autotomy on immune function and disease resistance of Portunus trituberculatus (Brachyura, Portunidae)

Crustaceana ◽

10.1163/15685403-bja10002 ◽

2020 ◽

Vol 93 (2) ◽

pp. 181-197

Author(s):

Xujie Wang ◽

Yingying Peng ◽

Huaihua Yu ◽

Wenjun Xu ◽

Hui Shi ◽

...

Keyword(s):

Disease Resistance ◽

Immune Function ◽

Self Regulation ◽

Portunus Trituberculatus ◽

Granular Cells ◽

Negative Effects ◽

Short Term ◽

Physiological Regulation ◽

Regulation Mechanisms ◽

Short Term Effects

Abstract Crustaceans usually autotomize their limbs in response to physical or physiological threats. In this study, the short term effects of different degrees of autotomy on immune function and disease resistance of Portunus trituberculatus were studied by autotomizing one limb (mild autotomy) or four limbs (severe autotomy). The results indicate that the total haemocyte count (THC) of these crabs showed a tendency to decrease rapidly at first, then increase, and then decrease after mild autotomy and severe autotomy, but the THC changes for individuals with mild autotomy lagged relatively behind. The haemocyte compositions of the crabs also changed greatly after limb autotomy; especially in the severe autotomy group, the proportion of large granular cells and non-granular cells increased significantly within 0.5 h and 2 h after treatment, and the proportion of small particle cells clearly decreased. From the changes in related immune enzyme activities, the effect of autotomy on the activity of haemolymph superoxide dismutase (SOD) in P. trituberculatus was notably low, but had a greater influence on the activities of phenoloxidase (PO), lysozyme (LZM), acid phosphatase (ACP) and alkaline phosphatase (AKP). Among these activities, PO activity decreased significantly within 1 h after treatment and then gradually recovered, LZM activity began to rise continuously within 4 h of autotomy, and both ACP and AKP activity increased immediately after treatment and then gradually decreased. Compared with the individuals with severe autotomy, the haemolymph immunoenzymatic activity of the mild autotomy crabs was slight and slower. In addition, limb autotomy directly affects the disease resistance of P. trituberculatus, especially for the case of severe autotomy, i.e., the resistance of P. trituberculatus to disease is significantly weakened, and the probability of death greatly increases. On the whole, P. trituberculatus could respond to the short term negative effects of limb autotomy by corresponding physiological regulation mechanisms, but the disease resistance was still reduced. This study showed that the self-regulation ability of P. trituberculatus in response to limb autotomy was limited, especially in the case of severe autotomy.

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Enhanced Disease Resistance to Enteric Speticemia in Channel Catfish,Ictalurus punctatus,Administered Lytic Peptide

Journal of Applied Aquaculture ◽

10.1300/j028v03n01_03 ◽

1994 ◽

Vol 3 (1-2) ◽

pp. 25-34 ◽

Cited By ~ 7

Author(s):

D. G. Kelly ◽

William R. Wolters ◽

J. M. Jaynes ◽

J. C. Newton

Keyword(s):

Disease Resistance ◽

Ictalurus Punctatus ◽

Channel Catfish ◽

Lytic Peptide

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Odorant receptors activated by amino acids in sensory neurons of the channel catfish Ictalurus punctatus.

The Journal of General Physiology ◽

10.1085/jgp.102.6.1085 ◽

1993 ◽

Vol 102 (6) ◽

pp. 1085-1105 ◽

Cited By ~ 19

Author(s):

T T Ivanova ◽

J Caprio

Keyword(s):

Amino Acids ◽

Amino Acid ◽

Ictalurus Punctatus ◽

Channel Catfish ◽

Olfactory Receptor ◽

Action Potentials ◽

Single Channel ◽

Odorant Receptors ◽

Olfactory Neurons ◽

Whole Cell

Odorant receptors activated by amino acids were investigated with patch-clamp techniques in olfactory receptor neurons of the channel catfish, Ictalurus punctatus. The L-isomers of alanine, norvaline, arginine, and glutamate, known to act predominantly on different olfactory receptor sites, activated nondesensitizing inward currents with amplitudes of -2.5 to -280 pA in olfactory neurons voltage-clamped at membrane potentials of -72 or -82 mV. Different amino acids were shown to induce responses in the same sensory neurons; however, the amplitude and the kinetics of the observed whole cell currents differed among the stimuli and may therefore reflect activation of different amino acid receptor types or combinations of receptor types in these cells. Amino acid-induced currents appeared to have diverse voltage dependence and could also be classified according to the amplitude of the spontaneous channel fluctuations underlying the macroscopic currents. A mean single-channel conductance (gamma) of 360 fS was estimated from small noise whole-cell currents evoked by arginine within the same olfactory neuron in which a mean gamma value of 23.6 pS was estimated from 'large noise' response to norvaline. Quiescent olfactory neurons fired bursts of action potentials in response to either amino acid stimulation or application of 8-Br-cyclic GMP (100 microM), and voltage-gated channels underlying generation of action potentials were similar in these neurons. However, in whole-cell voltage-clamp, 8-Br-cyclic GMP evoked large rectangular current pulses, and single-channel conductances of 275, 220, and 110 pS were obtained from the discrete current levels. These results suggest that in addition to the cyclic nucleotide-gated transduction channels, olfactory neurons of the channel catfish possess a variety of odor receptors coupled to different types of transduction channels.

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