Christopher C. Kohler

Southern Illinois University Carbondale | SIU · SIU Center for Fisheries, Aquaculture, and Aquatic Sciences

Feeding trials were conducted to determine (1) the optimal inclusion of poultry byproduct meal (PBM) and poultry fat (PF) as alternatives to fish meal (FM) and fish oil (FO) in diets for Largemouth Bass Micropterus salmoides and (2) whether the poultry-based formulations could be used in conjunction with FO-based finishing feeds in a strategy to mi...

Soluble canola protein concentrate (SCPC) is rich in glutamic acid and may act as a feed attractant to improve feed acceptance and production performance of fish fed plant‐based diets. In the first experiment, attractant properties of SCPC were evaluated by comparing production performance of sunshine bass, Morone chrysops × Morone saxatilis, fed r...

Los organismos ectotérmicos viven normalmente dentro de un rango específico de variación térmica, tanto que la vida fuera de ese rango puede ser difícil o letal. El cultivo de la gamitana Colossoma macropomum en el Perú, se haexpandido hacia áreas con distintas condiciones climáticas. En acuicultura, recientemente se han evaluado nuevos insumos y d...

We evaluated production performance and fillet composition of sunshine bass fed increasing levels of stabilized poultry protein meal (PM) and poultry fat (PO) to replace menhaden fish meal (FM) and/or oil (FO) in diets. The control diet included 200 g/kg (dry matter basis) FM and 98 g/kg FO. In eight treatment diets, 50% or 100% of the FM and/or FO...

The n-3 long chain polyunsaturated fatty acids (LC-PUFA) found in marine oils are essential for maximizing ova quality and embryonic survival of many finfish. However, larval survival is often independent of ova n-3 LC-PUFA content, and may depend on the presence of other nutrients (i.e., saturated fatty acids, SFA; or C18 PUFA) during the endogeno...

Larval fish were a frequent dietary component of alewives (Alosa pseudoharengus) from Claytor Lake, Virginia, USA. Alewives consumed the young of four game and two forage species (maximum 26 mm total length (TL)). Alewife piscivority appeared to be at least partially nocturnal and was more prominent in littoral than in limnetic areas. Predator and...

The extent to which flax oil can replace fish oil in diets fed to female broodstock of white bass Morone chrysops was determined by evaluating growth performance and the fatty acid (FA) profile of ovum lipid classes. Four experimental diets containing increasing levels of flax oil as 0, 33, 67, and 100% replacement of menhaden ( Brevoortia spp.) fi...

We evaluated white bass ovum fatty acid composition as well as embryonic and larval survival after varying n-3 and n-6 long-chain polyunsaturated fatty acid (LC-PUFA) concentrations in maternal diets. Diets containing graded levels (0, 33, 66, or 100%) of squid to menhaden oils were fed daily to apparent satiation to female white bass for 8 weeks p...

We evaluated production performance, fillet composition, and sensory integrity of sunshine bass (Morone chrysops x M. saxatilis) fed a marine oil-based finishing feed after being raised on a plant oil-based production feed. Two feeds containing either corn oil (CO) or menhaden oil (MO) were fed to sunshine bass according to different feeding regime...

Collingsworth, PD and Kohler, CC. 2010. Abundance and habitat use of juvenile sunfish among different macrophyte stands. Lake Reserv. Manage. 26:35-42.Juvenile Lepomis sunfish (< 75 mm total length, TL) density, plant stem density and invertebrate density were compared in the 3 most common habitats in the littoral zone of Cedar Lake, a Midwestern N...

The fatty acid (FA) composition of cultured finfish can be tailored by transitioning fish reared on alternative lipid-based, low long-chain polyunsaturated FA (LC-PUFA) content grow-out feeds to high LC-PUFA finishing feeds based on fish oil (FO) before harvest. To determine whether the FA composition of the grow-out feed influences finishing succe...

Collingsworth, P.D., R.A. Oster, C.W. Hickey, R.C. Heidinger and C.C. Kohler. 2009. Factors affecting water willow establishment in a large reservoir. Lake Reserv. Manage. 25:200–207.We evaluated the transplanting potential of an emergent macrophyte, water willow (Justicia americana), into Rend Lake, a large, relatively unvegetated reservoir in sou...

Traditionally fisheries biologists have used various metrics to indicate the condition and, by implication, health of fish. These indices are usually based on relationships between length and weight (Anderson and Neumann 1996). Although such metrics can, under some circumstances, provide a quick estimate of a fish’s condition, their ability to shed...

Abstract To facilitate economical culture of black pacu, Colossoma macropomum, and red pacu, Piaractus brachypomus, in the Amazon region of South America, we assessed locally available alternative energy sources for practical diets. We tested the effects of control diets (containing wheat products) versus diets with different Amazonian feedstuffs (...

We determined whether canola oil could spare menhaden oil (MO) in diets containing minimal fish meal without affecting sunshine bass, Morone chrysops × Morone saxatilis, production. Seven isonitrogenous, isocaloric (41.7% crude protein and 14.6% crude lipid) diets containing graded levels (0, 20, 40, 60, 80, or 100%) of menhaden to canola oils with...

Fatty acid (FA) profile of fish tissue mirrors dietary FA profile and changes in a time-dependent manner following a change in dietary FA composition. To determine whether FA profile change varies among lipid classes, we evaluated the FA composition of fillet cholesteryl esters (CE), phospholipids (PL), and triacylglycerols (TAG) of sunshine bass (...

We evaluated the effects of dietary vitamin E concentration and source on production performance and immunocompetency of sunshine bass, Morone chrysops × Morone saxatilis, following stress and disease challenge. Four diets were formulated to contain requisite levels (1×) or five times (5×) the vitamin E requirement of sunshine bass as met by synthe...

Fatty acid (FA) composition of fillet tissue can be tailored by transitioning fish from alternative lipid-based, low long-chain polyunsaturated fatty acid (LC-PUFA) grow-out feeds to high LC-PUFA "finishing" feeds. To address whether grow-out feed composition influences the responsiveness of fillet tissue to finishing, sunshine bass (SB, Morone chr...

We evaluated the effect of dietary natural source vitamin E (NSVE) on hematology and tissue composition of sunshine bass (female white bass Morone chrysops × male striped bass M. saxatilis) at rest and under the physical stress of exertion. Experimental diets were formulated to contain 1, 2, 5, or 30 times the dietary vitamin E requirement of sunsh...

The effect of using a finishing diet containing menhaden fish oil on the fatty acid composition of fingerling channel catfish, Ictalurus punctatus, was evaluated in a 12-wk growth trial. Three isocaloric, isonitrogenous practical diets with three different sources of lipids (menhaden oil [MO], catfish oil [CO], or beef tallow [BT]) were formulated...

A 7-week feed trial was conducted to determine the minimum dietary level of menhaden (Brevoortia spp.) meal (MM) needed to maintain growth, fillet quality, and health in sunshine bass (female white bass Morone chrysops × male striped bass M. saxatilis). Sunshine bass were stocked at 10 fish/tank (group weight per tank: Mean ± SD = 182.0 ± 2.0 g) in...

We evaluated the influence of three organic fertilizers—cottonseed meal, ground rice bran, and ground flaxseed—on the fatty acid composition of zooplankton and fingerling sunshine bass (female white bass Morone chrysops × male striped bass M. saxatilis). Flaxseed contains about 10-fold greater lipid and percent α-linolenic acid (18:3[n-3]); values...

We evaluated the effects of stressor exposure and super-requirement levels of RRR-atocopheryl acetate (natural-source vitamin E [NSVE]) on production performance and nonspecific immunocompetency of juvenile sunshine bass (female white bass Morone chrysops X male striped bass M. saxatilis). Stressor exposure elicited physiological changes consistent...

Growth rate, survival and body composition of muskellunge Esox musquinongy (initial mean total length = 125 mm) and tiger muskellunge E. masquinongy × E. lucius (initial mean total length = 115 mm) fed semi-purified diets differing in protein level from 31 to 40% and 34 to 45%, respectively, were evaluated in 8-wk trials. The minimum protein level...

— Fish possess a growth hormone similar to mammalian growth hormone, and the presence of a growth hormone-releasing hormone-like material in the brain has been demonstrated in several teleost species. We investigated the effect of a mammalian growth hormone-releasing hormone on serum estradiol-17β and testosterone concentrations in tilapia Oreochro...

The effects of a mammalian growth hormone-releasing hormone (GHRH), PrebGRF(1–78)OH (bGHRH), on growth and serum growth hormone (GH) levels were investigated in tilapias Oreochromis mossambicus andO. niloticus × O. aureus. Fish were injected intramuscularly or implanted intramuscularly (Silastic or cholesterol implants) with distilled water, 0.1 μg...

The plasmid vector, pBRd-AK1-BGH4.6.10 (pBGH), containing the bovine growth hormone sequence driven by an avian retroviral long terminal repeat (LTR) was microinjected at 0.1, 0.5, 1 or 5 ng of pDNA/20 nl of physiological saline into tilapia, Oreochromis mossambicus × O. niloticus embryos. In 24 replicates, normally 60 zygotes were microinjected wi...

Fingerling red tilapia (Oreochromis mossambicus±O. niloticus) were orally administered 17--methyltestosterone (MT) under a warmwater (27.0 ± 0.5 C) and coolwater (21.5 ± 0.5 C) thermal regime. In the warmwater experiment, fish received either 0, 1, 5, 10, 30, 60, or 100 mg MT/kg feed for 75 days. In the coolwater experiment, fish received 0, 10, or...

Nitrogenous waste control in aquaculture systems is necessary to maintain healthy animals and to meet effluent standards. Decreased ammonia production has been attained in traditional livestock production systems by adding extracts of Yucca shidigera to the feed or storage lagoon system. An extract of Yucca shidigera was fed to post yolk-sac and ju...

Broodstock pacu Piaractus brachypomus as well as their eggs during their embryonic development were exposed to either normoxia (5.5–7.5 mg O2/L) or hypoxia (2.0–4.5 mg O2/L) conditions. The plasma concentrations of 11-ketotestosterone in males and estradiol-17β in females, as well as that of their precursor testosterone (T) were significantly (P <...

Three hybrid tilapia (Oreochromis mossambicus ± O. niloticus) spawning families were established in three separate culture tanks to provide a continuous supply of fresh gametes. An ovulation event, resulting in a natural spawn, an artificial spawn or oocyte resorption, occurred with a mean of every 1.4 days among 19 females, though only a few femal...

We evaluated the influence of two broodstock feeding practices on fatty acid composition and viability of eggs in white bass Morone chrysops. The two dietary groups tested were (1) white bass females fed a commercially formulated feed (crude protein, 45%; crude fat, 16%) and (2) white bass females maintained on live food (fathead minnow Pimephales...

Marine oil-based finishing diets have been used to restore fillet FA profile in several "medium-fat" fleshed aquaculture species, and a simple dilution model describing FA turnover has been established to predict and tailor final fillet composition. We evaluated finishing diet efficacy and suitability of the dilution model to describe patterns of F...

We evaluated the effects of casein-based semipurified diets, alone or supplemented with native Peruvian plants, on growth, feed efficiency, and histology of the digestive tract of red pacu, Piaractus brachypomus, juveniles over an 8-wk feeding trial. Three tanks were randomly assigned to one of four casein-gelatin (40:8) diets containing a suppleme...

We stocked phase-III sunshine bass (white bass Morone chrysops ♀ × striped bass M. saxatilis ♂) at a rate of 6,188 fingerlings/ha into twelve 0.04-ha earthen ponds supplied with continuous aeration. Three dietary treatments were randomly assigned to quadruplicate ponds. Sunshine bass were fed to apparent satiation once daily after average initial w...

We evaluated the dietary effects of graded levels of highly unsaturated fatty acids (HUFAs) fed to broodstock female white bass Morone chrysops on reproductive performance, egg hatchability, and larval survival of sunshine bass (female white bass × male striped bass M. saxatilis) through the endogenous feeding stage. Dietary treatments consisted of...

Much of the criticism leveled at aquaculture (e.g., dependency on animal-derived feedstuffs, nutrient-laden effluent discharges, and increased organic contamination in edible products) can be traced to the feeds in use. Accordingly, finfish nutritionists are being challenged to formulate feeds that not only meet the nutritional requirements of live...

A variety of vitamin E isomers can be used in the manufacture of animal feeds, though the efficacy of these sources varies. Our purpose was to evaluate natural-source vitamin E, RRR-a-tocopheryl acetate (NSVE), as an alternative to synthetic vitamin E, all-rac-a-tocopheryl acetate (SYNE), in the diets of sunshine bass (female white bass Morone chry...

A look at fisheries statistics from a global perspective reveals a shift from capture fisheries to fish farming.

The terms “digestion” and “evacuation” are used interchangeably in studies of gastric processing in black basses Micropterus spp. We demonstrate that these processes are distinct and suggest that the differences may influence models involving the kinetics of gastric evacuation. Bolus (particulate matter) and residuum (bolus plus chyme (fluidized ga...

We compared consumption rates of bluegills Lepomis macrochirus by largemouth bass Micropterus salmoides and sunshine bass (female white bass Morone chrysops × male striped bass M. saxatilis) in structured (about 50% coverage with artificial vegetation) and nonstructured 2,000-L fiberglass tanks. In the presence of structure, instantaneous bluegill...

The replacement of menhaden Brevoortia spp. oil with graded levels of canola oil in diets fed for 20 weeks to sunshine bass (female white bass Morone chrysops X male striped bass M. saxatilis) significantly impacted the fatty acid composition of fillets and livers. As the amount of canola oil increased from 0% to 100% of the oil in the diet, the am...

A combination of increased human population growth, high fish harvest pressure, and adoption of more technologically advanced fishing equipment by the commercial fleet has generated concerns about the sustainability of fish stocks in the Peruvian Amazon. We assessed the status of the commercial fishery by conducting interviews with officials of the...

A floating vertical raceway is a system designed to provide a constant, unidirectional flow of water to fish confined in a flexible raceway that is suspended vertically in the water column. This study evaluated the potential of floating vertical raceways for the culture of phase-II sunshine bass (female white bass Morone chrysops × male striped bas...

Arapaima gigas Cuvier pond culture has been conducted in the ponds of five small-scale fish producers in Iquitos (Peru) for approximately one year using a prey-predator pond cultivation mode. The preliminary results obtained in this study demonstrate that A. gigas is an excellent candidate for aquaculture because of its excellent survival, fast gro...

Growth, survival, and proximate composition were evaluated in channel catfish Ictalurus punctatus fry and fingerlings fed one of three isocaloric practical diets (45% or 50% protein) containing 50, 65, or 75% meal from menhaden Brevoortia spp. in a recirculating aquaculture system. There were no significant differences in growth when the experiment...

En este artículo se analiza la posibilidad de cultivo de moluscos como, P. maculata, Anodontites trapesialis y otros en la Amazonía peruana con la finalidad de incremento de las fuentes de proteína para la alimentación de la población, incluyendo la posibilidad de producción comercial

White bass (Morone chrysops) broodstock were obtained from three locations in the United States encompassing the native range of this species: Arkansas River, AR; Lake Erie, near Cleveland, OH; and Lake Poinsett, SD. In spring 1996, white bass eggs of each strain were fertilized with fresh semen from the same strain or with extended striped bass (M...

White bass Morone chrysops were captured by hook and line from the Illinois River and transported for 5 h in either freshwater or water with 5‰ NaCl; they were then maintained in separate water reuse systems at their respective salinities. Blood plasma osmolality, semen osmolality, and semen motility were monitored for 57 h. Our objectives were to...

Differences in salinity tolerance and osmoregulatory performance between sunshine bass (white bass Morone chrysops ♀ × striped bass M. saxatilis ♂) and palmetto bass (striped bass ♀ × white bass ♂) were evaluated by using direct-transfer toxicity testing and monitoring of plasma osmolality during salinity elevation. The 24-h LC50 (concentration let...

Spawning trials were conducted to determine an efficacious dosage of human chorionic gonadotropin (hCG) and to investigate the potential of mammalian gonadotropin releasing hormone analog (mGnRHa) to induce ovulation in white bass Morone chrysops. White bass broodstock were habituated to indoor tanks and subjected over several months to photoperiod...

Aquaculture performance of phase II and phase III sunshine bass (a female white bass Morone chrysops × male striped bass M. saxatilis), palmetto bass (a female striped bass × male white bass), and white bass were evaluated in separate 12-week yield trials conducted in indoor recirculating-water systems. Phase II sunshine bass, palmetto bass, and wh...

Cold tolerance of striped bass Morone saxatilis, white bass M. chrysops, palmetto bass (female striped bass × male white bass), and sunshine bass (female white bass × male striped bass) were compared under controlled laboratory conditions. Two groups of each taxon were acclimated at 20°C in a recirculating-water system housed in an environmental ch...

Adult white bass can be collected from the wild, acclimated to captivity, trained to eat formulated feed, and, by manipulating temperature and photoperiod, induced to spawn (both in and out of season) using hCG injections. Hatchery and pond fry production techniques are basically the same as for sunshine bass. Considerably more research is needed t...

Channel catfish Ictalurus punctatus were induced to spawn out of season by means of photothermal and hormonal manipulations in indoor water-recirculating systems. Groups of fish were maintained under the following temperature regimes: annual, cycles of 9 months in cool water (17 ± 2°C) followed by 3 months at spawning temperatures (25-28°C); compre...

White tilapias, the hybrids of Nile tilapia Oreochromis niloticus × blue tilapia O. aureus, were rapidly hypophysectomized with a 2-mm, high-speed mototool cutter via an opercular approach. Two weeks post-hypophysectomy, serum cortisol levels were nondetectable in 98 of the surviving test fish. The remaining 6 test fish and the nonhypophysectomized...

Performances of sunshine bass, the hybrid of female white bass Morone chrysops × male striped bass M. saxatilis, were compared between fish reared in round and rectangular cages in ponds, between fish reared in round and rectangular indoor tanks equipped with biofilters, and between fish reared in ponds without confinement and in rectangular cages...

We report the first volitional tank spawning of female striped bass Morone saxatilis with male white bass M. chrysops. The female striped bass were reared for 6 or 8 years from larvae to mature adults in captivity. The wild-caught male white bass were acclimated to captivity 1 year before spawning trials. The fish were induced to mature with implan...