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Hepatic Microsomal N-Hydroxylation Of Aniline And 4-Chloroaniline By Rainbow Trout (Onchorhyncus Mykiss), Steven P. Bradbury, J. M. Dady, A. D. Hoffman, M. M. Voit, D. L. Olson Dec 1991

Hepatic Microsomal N-Hydroxylation Of Aniline And 4-Chloroaniline By Rainbow Trout (Onchorhyncus Mykiss), Steven P. Bradbury, J. M. Dady, A. D. Hoffman, M. M. Voit, D. L. Olson

Steven P. Bradbury

N-Hydroxylation of aniline and 4-chloroaniline was quantified in rainbow trout microsomal preparations using h.p.l.c.-liquid scintillation methods. Radioactive phenylhydroxylamine and 4-chlorophenylhydroxylamine metabolites were identified by co-elution with non-labelled standards. The method provided resolution of metabolite standards, and quantification of both N-hydroxylated metabolites was achieved without derivatization. The maximum velocities at 25 degrees C were 33.8 +/- 1.40 and 22.0 +/- 0.98 pmol/min per mg for aniline and 4-chloroaniline N-hydroxylation, respectively. The Km values were 1.0 +/- 0.11 and 0.8 +/- 0.11 mM for aniline and 4-chloroaniline N-hydroxylation, respectively. These activities were not induced by treatment of the trout with Aroclor 1254 …


Swine Responses To Constant And Modified Diurnal Cyclic Temperatures, Hongwei Xin, James A. Deshazer Nov 1991

Swine Responses To Constant And Modified Diurnal Cyclic Temperatures, Hongwei Xin, James A. Deshazer

Hongwei Xin

Ad libitum fed and individually penned crossbred gilts (39 ± 2 kg) were exposed to a constant air temperature of 30.8*" C (CON) and equal-mean diurnal cyclic temperatures cycling from 26° to 33*^ C (RPK) and from 23.4° to 40° C (RNT). Fluorescent lighting with an intensity of 800 to 1100 L/m/m2 was provided from 0600 h to 2100 h. Measurements of feed intake, heat loss rates, water usage, growth, and ingestion behavior were made for a five-day period and replicated six times. Daily average heat loss rates, water usage, and feed conversion of the RPK and RNT pigs could …


Stimulation Of Pheromone Biosynthesis In The Moth Helicoverpa Zea: Action Of A Brain Hormone On Pheromone Glands Involves Ca2+ And Camp As Second Messengers, Russell A. Jurenka, Emmanuelle Jacquin, Wendell L. Roelofs Oct 1991

Stimulation Of Pheromone Biosynthesis In The Moth Helicoverpa Zea: Action Of A Brain Hormone On Pheromone Glands Involves Ca2+ And Camp As Second Messengers, Russell A. Jurenka, Emmanuelle Jacquin, Wendell L. Roelofs

Russell A. Jurenka

Isolated abdomen and pheromone gland bioassays were utilized to determine the physiological action of the pheromone-biosynthesis-activating neuropeptide (PBAN) in the corn earworm moth Helicoverpa (= Heliothis) zea. An isolated pheromone gland bioassay showed that synthetic PBAN was active at 0.02 pmol, with maximal activity occurring at 0.5 pmol and 60 min of incubation. Second-messenger studies demonstrated that extracellular Ca2+ is necessary for PBAN activity on isolated pheromone glands. The Ca2+ ionophore A23187 stimulated pheromone biosynthesis alone, whereas the Ca2+ channel blockers La3+ and Mn2+ inhibited PBAN activity. However, the organic Ca2+ channel blockers verapamil and nifedipine did not inhibit PBAN …


Control Of Salmonella On Beef Tissue Surfaces In A Model System By Pre- And Post-Evisceration Washing And Sanitizing, With And Without Spray Chilling, James S. Dickson, Maynard E. Anderson Jul 1991

Control Of Salmonella On Beef Tissue Surfaces In A Model System By Pre- And Post-Evisceration Washing And Sanitizing, With And Without Spray Chilling, James S. Dickson, Maynard E. Anderson

James S. Dickson

Beef tissue was inoculated with a nalidixic acid resistant strain of Salmonella California and processed under conditions simulating pre- and post-evisceration carcass washing and sanitizing. These treatments, using distilled water to wash and 2% acetic acid to sanitize, reduced the population of salmonellae by as much as 2-log10 cycles when compared to samples which were washed only in distilled water. Increasing the acid temperature to 55°C reduced the bacterial populations further. Spray chilling, when used in series with the pre- and post-evisceration treatments, apparently resulted in recovery of some injured Salmonella.


Ferrous Fumarate Fortification Of A Chocolate Drink Powder, Richard F. Hurrell, Manju B. Reddy, Sandra A. Dassenko, James D. Cook, David Shepherd Mar 1991

Ferrous Fumarate Fortification Of A Chocolate Drink Powder, Richard F. Hurrell, Manju B. Reddy, Sandra A. Dassenko, James D. Cook, David Shepherd

Manju B. Reddy

An evaluation was made into the usefulness of ferrous fumarate as an iron fortificant for an experimental chocolate drink powder targetted to children and adolescents. Organoleptically ferrous fumarate was acceptable when the chocolate drink powder was reconstituted in milk or water that was heated to < 80". Unacceptable colour changes occurred, however, when boiling milk or water were used. In human Fe absorption studies when the Fe compounds were added to the chocolate drink immediately before consumption, ferrous fumarate was 3.31 % absorbed compared with 2.82% for ferrous sulphate and 2.11 % for ferric pyrophosphate. When the Fe compounds were processed during the manufacture of the chocolate drink powder, the absorption of ferrous fumarate was 5.27 %, ferrous sulphate 2.62 'YO and ferric pyrophosphate 0.55 %. Ascorbic acid had little or no effect on the absorption of ferrous fumarate. It is concluded that food processing can influence the relative absorption of fortification Fe and that, if not reconstituted with boiling milk or water, ferrous fumarate could be a useful compound for the fortification of chocolate drink powders.


Interaction Of Insecticide Resistance Genes In Field Populations Of Culex Pipiens (Diptera: Culicidae) From Italy In Response To Changing Insecticide Selection Pressure, Bryony C. Bonning, J. Hemingway, R. Romi, G. Majori Mar 1991

Interaction Of Insecticide Resistance Genes In Field Populations Of Culex Pipiens (Diptera: Culicidae) From Italy In Response To Changing Insecticide Selection Pressure, Bryony C. Bonning, J. Hemingway, R. Romi, G. Majori

Bryony C. Bonning

Culex pipiens Linnaeus larvae were collected from various locations in Italy and colonized as separate strains. These were analysed for elevated nonspecific esterase activity and frequency of altered acetylcholinesterase (AChE) mechanisms of insecticide resistance, and bioassayed, to define the cross-resistance spectra conferred by these to organophosphorus and carbamate insecticides. These mechanisms were further characterized by polyacrylamide gel electrophoresis. Elevated esterase A1 (formerly known as Est 3A) which predominated in C. pipiens from Italy in 1985 had been replaced by two esterases, A2 and B2. Altered acetylcholinesterase was still present at high frequencies. Altered and normal acetylcholinesterase were distinguished by differential …


Basic Alfalfa Germplasms Differ In Nutritive Content Of Forage, Andrew W. Lenssen, E. L. Sorensen, G. L. Posler, L. H. Harbers Mar 1991

Basic Alfalfa Germplasms Differ In Nutritive Content Of Forage, Andrew W. Lenssen, E. L. Sorensen, G. L. Posler, L. H. Harbers

Andrew W. Lenssen

Little information is available regarding comparative forage quality of alfalfa (Medicago sativa L.) leaves and stems of the nine germplasms from which most North American cultivars have been developed. In a greenhouse trial, forage quality of leaves and stems of the nine germplasms was compared when grown in a common environment and harvested at the same phenological stage. Germplasm sources (and representative cultivar) tested were: Indian (Sirsa #9), African (African), Peruvian (Hairy Peruvian), Flemish (DuPuits), Turkistan (Lahontan), Chilean (Kansas Common), M. varia Martin (Grimm), Ladak (Ladak), M. falcata L. (Anik). Leaves of germplasm sources differed for concentrations of neutral detergent …


Contamination Of Beef Tissue Surfaces By Cattle Manure Inoculated With Salmonella Typhimurium And Listeria Monocytogenes, James S. Dickson Feb 1991

Contamination Of Beef Tissue Surfaces By Cattle Manure Inoculated With Salmonella Typhimurium And Listeria Monocytogenes, James S. Dickson

James S. Dickson

Contamination of beef lean and fat tissue surfaces by Salmonella typhimurium and Listeria monocytogenes was evaluated using phosphate buffer or sterilized manure as an inoculation menstruum. Immersion in inoculated phosphate buffer resulted in an increase in numbers of attached cells during the 120 min inoculation for both bacterial species. Tissue immersed in inoculated manure generally showed an increase in cell numbers up to 10 min of immersion with only slight increases in cell numbers from lOto 120 min. Fewer cells attached to either tissue type from the manure inoculum (P<0.05), although actual numerical differences were small.


Inhibition Of Alcohol Dehydrogenase Activity By Acetylenic And Allylic Alcohols: Concordance With In Vivo Electrophile Reactivity In Fish, Steven P. Bradbury, Glenn M. Christensen Jan 1991

Inhibition Of Alcohol Dehydrogenase Activity By Acetylenic And Allylic Alcohols: Concordance With In Vivo Electrophile Reactivity In Fish, Steven P. Bradbury, Glenn M. Christensen

Steven P. Bradbury

Acetylenic and al!ylic alcohols have been reported to be 20 to 5,000 times more acutely toxic to fathead minnows (Pimephales promelas) than would be expected from a narcosis-based mechanism of action. The greater-than-expected toxicity of these alcohols has been proposed to be a result of metabolic activation to the corresponding reactive a ,)3-unsaturated aldehydes or allene derivatives. Using purified horse liver and rainbow trout (Oncorhynchus mykiss) hepatic cytosol alcohol dehydrogenase (ADH) preparations, the propensity of a series of acetylenic and allylic alcohols to inhibit enzyme activity, in both the presence and the absence of reduced glutathione, was ascertained. Those alcohols …


Use Of Respiratory-Cardiovascular Responses Of Rainbow Trout (Oncorhynchus Mykiss) In Identifying Acute Toxicity Syndromes In Fish: Part 4. Central Nervous System Seizure Agents, Steven P. Bradbury, Richard W. Carlson, Gerald J. Niemi, Tala R. Henry Jan 1991

Use Of Respiratory-Cardiovascular Responses Of Rainbow Trout (Oncorhynchus Mykiss) In Identifying Acute Toxicity Syndromes In Fish: Part 4. Central Nervous System Seizure Agents, Steven P. Bradbury, Richard W. Carlson, Gerald J. Niemi, Tala R. Henry

Steven P. Bradbury

The respiratory-cardiovascular responses of spinally transected rainbow trout to acutely lethal concentrations of chlorpyrifos, cypermethrin, fenvalerate, endosulfan, endrin, and strychnine were examined. Common to all six toxicants, the most striking change in respiratory-cardiovascular parameters was an increased cough frequency. Ventilation frequency and volume dropped in strychnine-exposed trout, but both remained near predose levels (frequency) or elevated (volume) in the pyrethroid- and cyclodiene-exposed trout. In chlorpyrifos-intoxicated trout, ventilation frequency decreased while volume increased. Oxygen consumption remained near predose levels in the chlorpyrifos-, pyrethroid-, and strychnine-exposed trout, but increased dramatically in the cyclodiene-exposed trout. Arterial oxygen, carbon dioxide, and pH declined in …


Lignin Distribution In Thermomechanically Pulped Wood Fibers Via X-Ray Microanalysis, Douglas Stokke, Xuerong Wang Jan 1991

Lignin Distribution In Thermomechanically Pulped Wood Fibers Via X-Ray Microanalysis, Douglas Stokke, Xuerong Wang

Douglas D. Stokke

The three major framework organic constituents of the secondary xylem (wood) of trees are cellulose, hemicelluloses, and lignin. Lignin imparts a number of important physical properties to the woody cell wall. In addition, lignin serves as the "cement" which binds cells together, and is the material which must be softened, altered, or removed during pulping processes. The distribution of lignin within pulp cell walls is of importance with respect to use of the pulp fibers. In this study, x-ray analysis was used to investigate lignin distribution in thermomechanically pulped (i.e., pulped with heat and pressure, with no chemical treatment) aspen …


Flight Times Of Africanized And European Honey Bee Drones (Hymenoptera: Apidae), Richard L. Hellmich Ii, Thomas E. Rinderer, Robert G. Danka, Anita M. Collins, D. L. Boykin Jan 1991

Flight Times Of Africanized And European Honey Bee Drones (Hymenoptera: Apidae), Richard L. Hellmich Ii, Thomas E. Rinderer, Robert G. Danka, Anita M. Collins, D. L. Boykin

Richard L Hellmich

Flight activities of Africanized honey bee (Apis mellifera L.) drones were compared with those of two color morphs of European drones in Venezuela. European drones departed from colonies 19 +/- (mean +/- SEM) min earlier, and flight times were more variable than those of Africanized drones. Mean flight time differences decreased as the drones aged and were similar whether drones were flying from Africanized or European colonies. Overlap of their flight distributions was > 70%, which suggests that interbreeding of the two types of bees will be substantial under most natural conditions. Black and yellow European drones flew at similar times …


Response Of Africanized And European Honey Bees To Lactose In Sucrose Syrup, H. Allen Sylvester, Richard L. Hellmich Ii, Anita M. Collins Jan 1991

Response Of Africanized And European Honey Bees To Lactose In Sucrose Syrup, H. Allen Sylvester, Richard L. Hellmich Ii, Anita M. Collins

Richard L Hellmich

Application of biotechnology to control Africanized honey bees may be possible by genetically engineering domestic honey bee stocks to be resistant to some agent which is toxic or debilitating to Africanized bees. The agent could then be made available to forages in an area, and susceptible wild colonies, including Africanized honey bees, would be controlled.


Depression Of Forage Quality Of Alfalfa Leaves And Stems By Acyrthosiphon Kondoi (Homoptera: Aphididae), Andrew W. Lenssen, Edgar L. Sorensen, Gerry L. Posler, Sue L. Blodgett Jan 1991

Depression Of Forage Quality Of Alfalfa Leaves And Stems By Acyrthosiphon Kondoi (Homoptera: Aphididae), Andrew W. Lenssen, Edgar L. Sorensen, Gerry L. Posler, Sue L. Blodgett

Andrew W. Lenssen

ACYTthosiphon kondoi Shinji is a major pest of alfalfa (Medicago sativa L.). Susceptible seedling plants are killed by A. kondoi, and established plants suffer yield loss by stunting. Information is meager on the influence of A. kondoi infestation or host plant resistance on forage quality of alfalfa leaves and stems. In a controlled environment, the forage quality (includingphenolic monomers)of alfalfagermplasmsKSI53P4and KS153BA3P4 (susceptible and resistant to A. kondoi, respectively) with and without A. kondoi infestation was compared. Leaves infested with A. kondoi had lower concentrations of crude protein and true in vitro digestible dry matter (TIVDDM) than uninfested leaves of controls, …


Resistance To Anthracnose Protects Forage Quality Of Alfalfa, Andrew W. Lenssen, G. L. Posler, E. L. Sorenson, D. L. Stuteville Jan 1991

Resistance To Anthracnose Protects Forage Quality Of Alfalfa, Andrew W. Lenssen, G. L. Posler, E. L. Sorenson, D. L. Stuteville

Andrew W. Lenssen

Anthracnose, caused by Colletotrichum trifolii Bain, decreases forage yield and stand persistence of alfalfa (Medicago sativa L.) throughout much of the USA. Little is known about the effects of anthracnose or host-plant resistance on forage quality, including phenolic monomer concentrations. In a controlled environment, we compared forage quality, including phenolic monomers, of alfalfa cultivars Saranac (susceptible) and Saranac AR (resistant) with and without anthracnose (Race 1). In the absence of inoculation, leaves of the two cultivars did not differ significantly for any parameter measured. Leaves had more total phenolics than did stems. Forage quality of inoculated leaves of Saranac often …


Attachment Of Salmonella Typhimurium And Listeria Monocytogenes To Glass As Affected By Surface Film Thickness, Cell Density, And Bacterial Motility, James S. Dickson, E. K. Daniels Jan 1991

Attachment Of Salmonella Typhimurium And Listeria Monocytogenes To Glass As Affected By Surface Film Thickness, Cell Density, And Bacterial Motility, James S. Dickson, E. K. Daniels

James S. Dickson

With equal cell densities, surface film thickness did not influence the numbers &Salmonella typhimurium and Listeria monocytogenes cells which attached to glass. Motile L. monocytogenes cells had a greater cell surface charge and generally attached in higher numbers than non-motile cells.


Control Of Salmonella Typhimurium, Listeria Monocytogenes, And Escherichia Coli 0157:H7 On Beef In A Model Spray Chilling System, James S. Dickson Jan 1991

Control Of Salmonella Typhimurium, Listeria Monocytogenes, And Escherichia Coli 0157:H7 On Beef In A Model Spray Chilling System, James S. Dickson

James S. Dickson

Simulated water spray chilling cycles were modified to include acetic acid as a sanitizer. The modified cycles were tested for effectiveness in reducing levels of S. typhimutium, L. monocyfogenes, and E. coli 0157:H7 on beef lean and fat tissue. Reductions of up to 3 log cycles were obtained for all three bacterial species on fat tissue. Reduction was less on lean tissue with the same treatments, although the modified cycles reduced populations when compared to the control cycle.


Storage And Bacterial Contamination Effects On Myofibrillar Proteins And Shear Force Of Beef, James S. Dickson, John D. Crouse, M. Koohmaraie Jan 1991

Storage And Bacterial Contamination Effects On Myofibrillar Proteins And Shear Force Of Beef, James S. Dickson, John D. Crouse, M. Koohmaraie

James S. Dickson

Thirty-two steaks from the longissimus muscle, fifth rib to third lumbar vertebra, were obtained from youthful carcass beef. Half were sterilized by ultraviolet light and all vacuum packaged and stored for 1, 14, 28 or 57 days at 2°C. After storage, steaks were examined for microbial populations, myofibril fragmentation index (MFI), cooking characteristics and shear force (SF). Aerobic and anaerobic counts decreased during storage. Psychrotrophic counts were low throughout. Sterilization had no effect on SF or MFI. Cooking loss tended (P < 0.09) to increase with time of storage. SF values decreased and MFI values increased through day 14, but remained relatively constant after that. Results of SDS-PAGE, SF and MFI indicate major changes in proteolysis of myofibrils and tenderness were completed by day 14.


Attachment Of Salmonella Typhimurium And Listeria Monocytogenes To Beef Tissue: Effects Of Inoculum Level, Growth Temperature And Bacterial Culture Age, James S. Dickson Jan 1991

Attachment Of Salmonella Typhimurium And Listeria Monocytogenes To Beef Tissue: Effects Of Inoculum Level, Growth Temperature And Bacterial Culture Age, James S. Dickson

James S. Dickson

The effects of inoculum level, growth temperature and culture age on the attachment of Salmonella typhimurium and Listeria monocytogenes to beef tissue surfaces were evaluated. An increase in inoculum level resulted in an increase in the number of attached cells for both bacteria which was proportional to the increase in inoculum. Bacteria grown at 23°C attached in higher numbers flVO5) to fat tissue than bacteria grown at 37°C or at 37°C followed by 24 h at 5°C. Growth temperature did not affect attachment to lean tissue for either bacterium. Overnight cultures of both bacteria attached in greater numbers 0VO.05) to …