Most veterinary surgeons associate the capture of deer with projectile darts and immobilising drugs, but techniques for physical capture are used extensively particularly in deer farming and for ecological studies. The paper describes these different methods and the circumstances appropriate to their use.
No abstract is provided for this article.
Examination of samples of deep litter poultry manure which caused growth deformation in vegetable crops resulted in the isolation of a potent phytotoxic compound. The chemical properties and symptoms produced by tomato plants grown under hydroponic conditions, showed that it was not 2,4‐ D as suggested by other workers but a nitrogen heterocyclic compound with an attached carboxyl group. Poultry trials have shown that an impurity, 4‐amino‐3,5‐dichloro‐2,6‐lutidine, in the coccidiostat clopidol (3,5‐dichloro‐2, 6‐dimethyl‐4‐pyridinol) causes similar phytotoxicity. Increased potency after poultry ingestion indicates that this impurity is metabolised. The most likely metabolite is 4‐amino‐3,5‐dichloro‐6‐methyl picolinic acid. Chemical and physical data of the metabolite are identical to that of the toxic compound isolated from original manure samples. Detailed symptomology produced by the toxic manure on tomato plants is described.
Development of a novel inoculation technique to improve the current methods of determining the leaching of Escherichia coli O157:H7 from faeces.Ruminant faeces were inoculated with a high [c. 10(7) colony forming units (CFU) g(-1)] or low (c. 10(4) CFU g(-1)) load of a lux-marked strain of E. coli O157:H7 via injection, and subjected to four simulated heavy rainfall events. The population density and metabolic activity of E. coli O157:H7 recovered within the leachate was determined following each simulated rain event and compared with the indigenous E. coli population. The concentration of E. coli O157:H7 in the leachates followed a similar trend to that of nonpathogenic E. coli. Significantly greater densities of generic and pathogenic E. coli were recovered in the leachates generated from sheep faeces compared with cattle faeces. Pathogen metabolic activity was also significantly greater in sheep faeces.Our findings show that E. coli O157:H7 may readily leach from ruminant faeces during rain events. The bacterium leaches more freely from sheep faeces than from cattle faeces and displays greater metabolic activity within sheep leachate.A novel inoculation technique was developed that allowed the determination of both population density and cellular activity of E. coli O157:H7 in leachate derived from faeces.
To quantify the impact of organophosphate pesticides on aquatic ecosystems requires a mechanistic understanding of their behaviour in a range of environmental matrices. The objective of this study was to compare the sorption/desorption, biodegradation and toxic effects of the Pestanal® grade and commercial formulation (Ectomort Centenary) of the organophosphate insecticide propetamphos in river and estuarine sediments. For both formulations, the sorption of propetamphos onto sediment was initially very rapid followed by a slower sorption phase. Similarly, the initial rate of desorption was rapid, followed by a much slower rate. In both sorption and desorption experiments, the level of sorbed propetamphos was considerably higher for the commercial formulation of propetamphos (K d =7–11) than for the Pestanal® grade (K d =4–10). The rate of propetamphos biodegradation was sediment dependent but was most rapid where microbial activity and nutrients were the highest and sorption was the lowest. Propetamphos was more rapidly degraded in sediments under aerobic (t 1/2 =15 d) compared to anaerobic conditions (t 1/2 =19 d). However, no significant difference in the biodegradation rates of the Pestanal® grade and commercial formulations of propetamphos were observed. The toxic effect of propetamphos on sediment microbial communities was significantly greater for the commercial formulation than for the Pestanal® grade of propetamphos based on EC50 (21 versus 236 μg g− 1) and EC10 values (0.3 versus 54 μg g− 1). In conclusion, our results highlight the importance of using commercial pesticide formulations when carrying out ecotoxicological testing.
Bioreduction is a novel method for the on-farm storage of fallen stock in a vessel containing water that is heated and aerated, prior to disposal. The combination of a mesophilic temperature and high bacterial population leads to rapid degradation of carcasses due to microbial and enzymatic breakdown of protein material; and ultimately the reduction in volume of waste to be disposed. The system could, however, be improved if more was known about the changes that occur during a bioreduction cycle. Pig carcasses were placed within two commercial-scale bioreduction vessels (BVs) (6.5 m3 capacity) and the changes in physicochemical parameters, enzymatic activity, gas emissions and microbial communities were analysed over 56 days. Analyses showed that each vessel displayed different physicochemical parameters. The microbial communities within both vessels were also distinct, though they converged between days 28 and 42 before again diverging. Of the enzymes assayed, acetylesterases showed the highest activity during initial stages, with a subsequent increase in lipase towards the end. All other enzymes showed little activity in comparison. Despite active aeration of the vessels, conditions were redox-constrained, leading to the emission of gases associated with anaerobic conditions, namely NH3 and H2S. It was concluded that no single parameter governed the biochemical processes and that each BV will have its own unique microbial population and hence rate of decomposition. Further work is needed to increase the rate of bioreduction through bioaugmentation or developing enzyme additives.
Cyanobacteria living epiphytically on mosses in pristine, unpolluted areas fix substantial amounts of atmospheric nitrogen (N) and therefore represent a primary source of N in N-limited boreal forests. However, the fate of this N is unclear, in particular, how the fixed N2 enters the soil and becomes available to the ecosystem. In this study, we applied 15N-ammonium chloride (15N-NH4Cl) onto carpets of the feather moss Pleurozium schreberi and traced the 15N label into green (living) and brown (senescent) moss and into the upper soil layer over time. Further, we placed filters between moss and soil to assess the role of moss-associated fungi for N-transfer to the soil. The experiment was conducted at endpoints of a N2 fixation gradient in Northern Sweden. Feather moss retained the applied N in the green moss parts for up to 1 year and no increase of excess 15N was found in the brown moss parts or in the soil within that same time frame. The filter treatment did not alter the 15N-distribution in moss or soil. Nitrogen retention in the moss was similar regardless of position along the N2 fixation gradient. Our results suggest that mosses represent a short-term inorganic N sink and that transfer of N to the soil is not facilitated by fungal hyphae.
No abstract is provided for this article.
An apparatus is described for studying the interaction between soil fungi and the growth of higher plants in the presence of specific phytotoxins. At concentrations above 1 mm, caffeic and vanillic acids inhibited the growth of Pisum sativum cultured in nutrient solutions under axenic conditions. Soil fungi capable of using phenolic acids as energy sources were isolated from soil on kaolin aggregates into which a phenolic acid had been incorporated. Some of the fungi (Volutella ciliata, Gliocladium roseum and a Penicillium sp.) were isolated on to agar plates and grown in nutrient solutions containing a specific phenolic acid. One of the fungal isolates, V. ciliata, was compared with an XAD-4 resin, for effectiveness in reducing a phytotoxic concentration of vanillic acid towards the growth of pea seedlings. Reducing the concentration of vanillic acid from 1 to 0.2 mm enhanced the growth of the main root and increased the number of laterals so that the root system resembled that of control plants without the phenolic acid. The precise effect depended on the age of the plant when the phytotoxic concentration of the vanillic acid was reduced. At a 1 mM concentration of NO3-N (10% of concentration in the usual nutrient solution), concentrations as low as 10 μm vanillic acid were phytotoxic towards the growth of pea seedlings, and this effect was also ameliorated by V. ciliata. The V. ciliata produced no phytotoxins per se. Reducing phytotoxic concentrations of vanillic acid during the first 3 days of culture was more effective than subsequent reduction, and after 8 days the plants did not recover subsequently.
Options for the storage and disposal of animal carcasses are extremely limited in the EU after the introduction of the EU Animal By-products Regulations (ABPR; EC/1774/2002), leading to animosity within the livestock sector and the call for alternative methods to be validated. Novel storage technologies such as bioreduction may be approved under the ABPR provided that they can be shown to prevent pathogen proliferation. We studied the survival of Enterococcus faecalis, Salmonella spp., E. coli O157 and porcine parvovirus in bioreduction vessels containing sheep carcasses for approximately 4 months. The vessels were operated under two different scenarios: (A) where the water within was aerated and heated to 40 °C, and (B) with no aeration or heating, to simulate vessel failure. Microbial analysis verified that pathogens were contained within the bioreduction vessel and indeed reduced in numbers with time under both scenarios. This study shows that bioreduction can provide an effective and safe on-farm storage system for livestock carcasses prior to ultimate disposal. The findings support a review of the current regulatory framework so that bioreduction is considered for approval for industry use within the EU.
