Remediation of Pesticide Contaminated Soil by Planting and Compost Addition

Pesticide contaminated material was obtained from an agrichemical retail facility in Illinois. In an effort to improve physical properties and increase microbial activity and plant growth in the contaminated matrix, the material was mixed with uncontaminated soil or with mature yard waste compost to determine the impact of compost compared to soil on plant establishment and growth, development of soil microbial activity, and herbicide inactivation. Plant growth, particularly weed growth, was significantly greater in compost containing mixes than it was in soil mixes. Microbial activity, as measured by dehydrogenase activity, was significantly higher in compost-containing mixes than in soil mixes. The combination of planting and compost addition resulted in significant increases in herbicide inactivation in the contaminated materials. The results strongly suggest that remediation of herbicide contamination at agrichemical retail facilities can be achieved quite rapidly and at moderate cost and also demonstrate that the combination of compost addition and planting can accelerate xenobiotic degradation in contaminated soils.     

Limitations of atp estimates of microbial biomass

Serious limitations were found in the use of ATP measurements as indicators of Pseudomonas paucimobilis biomass and activity in sterilized soil. These limitations were related to effects of moisture stress, nutrient variation and protozoan predation on soil ATP levels and ATP per bacterium. Rewetting dry soil resulted in an increase (2.2-fold) in ATP per bacterium, as did additions of glucose (5.9-fold) and (NH₄)₂SO₄ (2.8-fold). ATP per bacterium also differed between grazed and ungrazed bacteria. Carbon dioxide evolution and ATP concentrations varied independently with time. Thus, except under low nutrient conditions, when neither bacterial numbers nor ATP measurements changed, ATP concentrations did not indicate bacterial population dynamics or respiration. Carbon and nitrogen effects on ATP concentrations were reduced by adding an excess of glucose a few hours before ATP measurements.     

Instructional practices at Farm Safety 4 Just Kids (FS4JK) safety day camps

The instructional methods used with 1,347 youth in seven Farm Safety 4 Just Kids (FS4JK) day camp sessions conducted in five states during the summer and fall of 2002 were videotaped. The videotapes, instructor questionnaires, and day camp materials were analyzed using an observation protocol that focused on instructional practices and an interaction analysis of instructor-student talk during the sessions. Results showed that instruction focused on hazard recognition, a high level of participant attention during all the sessions observed, and safety day camp content relevant to rural participants regardless of whether they live or work on a farm. Recommendations for improving instructional practice include better use of print materials, more interactive, participatory activities for students, and reduction of instructor-centered, didactic approaches. Given the high level of students' attention, increased involvement of students in active, participatory approaches might enhance the effectiveness of the instruction by: (1) further engaging students through personalizing hazard recognition, (2) contextualizing reports of injuries, (3) examining the complexities of choosing safe behaviors, and (4) paying more attention to the consequences of injury events. Role-playing, narrative simulations, and other types of interactive and collaborative exercises are instructional approaches that support the inclusion of the pre-event contingencies and post-event consequences that are part of all injury events.     

Dermatophytosis in show lambs in the United States

A dermatophytosis, called 'club lamb fungus' by owners, has been affecting show lambs during the lamb show season. Thirty-one families of 108 responding to a questionnaire reported at least one case of dermatophytosis, and 15 of those 31 families reported children or owners involved in showing these lambs developing skin lesions consistent with dermatophytosis. In lambs, gross lesions typical of ovine derma-tophytosis were located on all parts of the body, and consisted of circular areas of matted wool, crusts and discoloration. Lesions appeared either at a single site or were distributed randomly, affecting head, body and extremities. Direct microscopic examination of wool revealed ectothrix, endothrix, and combined endothrix and ectothrix infections. Microsporum gypseum was the only dermatophyte cultured from wool samples collected from affected lambs; however, the presence of endothrix spores suggests that other species may be involved. Arthrospores and fungal hyphae typical of dermatophytes were present in histological sections.     

Antimicrobial susceptibility and multi-drug resistance of Salmonella enterica subspecies enterica serovars in Sudan

This study was undertaken to determine the antimicrobial resistance patterns of Salmonella enterica subspecies enterica recovered from human, food, water, and animal samples collected in Khartoum State, Sudan. A total of 64 Salmonella isolates belonging to 28 different serovars were tested for their susceptibility to 13 antimicrobial agents. The majority of isolates (98.4 %) were resistant to at least one antimicrobial agent. Isolates were frequently resistant to ampicillin (90.6 %), cephalexin (50.0 %), nalidixic acid (25.0 %), streptomycin (21.9 %), kanamycin (18.8 %), gentamicin (17.2 %), and co-trimoxazole and trimethoprim (12.5 %). The most common pattern of multiple drug resistance included resistance to ampicillin and cephalexin. Most isolates were sensitive to chloramphenicol (98.4 %), ciprofloxacin (93.8 %), and norfloxacin (90.6 %). Two chicken- and the two human-origin S. Kentucky isolates were resistant to both ciprofloxacin and norfloxacin. All S. Kentucky isolates and the one S. Rissen isolate demonstrated multi-drug resistance. The results indicate the significance of multi-drug-resistant Salmonella serovars isolated from chickens and other animals and foods as sources for multi-drug-resistant Salmonella in humans in Sudan.     

Effect of transport on feeder calves

One hundred fifty feeder steers (mean body weight, 195 kg) were assigned to 1 of 3 transport groups and were deprived of feed and water (fasted) for 24 hours. Additionally, calves were transported on a commercial livestock trailer for 0 (control-fasted only), 12 (short haul), or 24 (long haul) hours. Blood samples were obtained from the jugular vein before calves were loaded on the transport vehicle and immediately after calves of the long-haul group returned to the research feedlot. Complete blood counts were performed and 32 mineral, enzyme, and biochemical constituents were measured. Calf morbidity, mortality, and average daily weight gain were evaluated during the next 56 days. Duration of transport did not affect average daily gain; however, calves of the short-haul group had significantly (P less than 0.05) higher morbidity and mortality than did those of the control and long-haul groups. In all groups, results of differential leukocyte counts were indicative of stress response. Significant (P less than 0.05) linear contrasts were observed between duration of transport and erythrocyte, leukocyte, segmented neutrophil, lymphocyte, and eosinophil counts and results of serum enzyme (alanine transaminase, hydroxybutyrate dehydrogenase, total lactate dehydrogenase [LD], and LD-1, LD-3, and LD-4 isoenzymes), iron, urea nitrogen, beta-globulin, glucose, and urea nitrogen-to-creatinine ratio determinations. Significant (P less than 0.05) quadratic contrasts were observed between duration of transport and serum unsaturated iron binding capacity, total iron binding capacity, and LD-5 percentage. Calf source had a significant (P less than 0.05) effect on almost all variables tested.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of an oil-based substrate (The Water Cleanser™) and bacterial additives on nitrogen and phosphorous dynamics in freshwater crayfish (Cherax cainii,Austin and Ryan 2002) aquaculture

Two experiments were conducted to evaluate the efficacy of an oil-based substrate, The Water Cleanser? (TWC). The first experiment studied the effects two substrates of different oil composition (TWC, TWC?+), and a commercial bacterial additive (Bio-Aid) on concentrations of nitrogen and phosphorous in indoor aquaria. The second experiment studied the effects of TWC, a bacterial additive, and a combination (TWC?+?B) on concentrations of nitrogen and phosphorous, phytoplankton abundance and diversity in outdoor freshwater crayfish (Cherax cainii, Austin and Ryan, Invertebr Syst 16:357–367, 2002) tanks. In the first experiment, the concentration of TAN decreased more rapidly with Bio-Aid, whilst the maximum concentrations of NO₂-N and NO₃-N were reduced with the substrates. The concentration of orthophosphate was reduced in aquaria with TWC?+?. In the second experiment, concentrations of TAN, NO₂-N, NO₃-N and total phosphate were not significantly affected by TWC. After addition of TWC?+?B, there was a significant decrease in the concentrations of nitrate and total phosphate, and a higher abundance of phytoplankton was maintained than with other treatments. Additionally, a population Bacillus sp. was found on the substrate surface. TWC had no adverse effects on phytoplankton abundance or diversity, or C. cainii physiology, weight gain or survival. TWC and TWC?+?were effective bioremediators of eutrophic water, whilst a combination of TWC?+?B was effective in short term bioremediation and in promoting phytoplankton abundance in C. cainii tank culture.