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41.
Global Assessment of Human-Induced Soil Degradation 总被引:1,自引:0,他引:1
Soil is a valuable natural resource that in the short - term is nonrenewable and is difficult to reclaim when degraded. The use of soils on a sustainable basis requires that their capability to withstand the demands upon them is not exceeded. Those people concerned with conservation should be aware of the vital importance of soil for maintaining food supplies for an increasing world population. Increasing demands place a greater strain upon the soil. If the demands become too great, the soil becomes degraded. As soil is the basis of all terrestrial ecosystems, a degraded soil means lower fertility, reduced biodiversity, and human poverty. To provide basic information on soil degradation worldwide, a survey of soil loss through erosion, physical deterioration, and chemical pollution was made. Digital databases are not available to hold information necessary to monitor and combat soil degrada tion at global and national scales. Soil degradation is recognized as a serious and widespread problem, so in September 1987 the International Soil Reference and Information Centre was commissioned to make a survey for a map at a scale of 1:10,000,000 entitled "Global Assessment of Human - Induced Soil Degradation" (GLASOD). Until it was published in 1990, there was no uniformly collected body of information on soil degradation worldwide. The GLASOD survey provides basic data on the world distribution and intensity of erosional, chemical, and physical types of degradation. The original purpose of GLASOD was to provide factual information, to replace sweeping statements about soil and land degradation, and to raise awareness of policy makers and governments for the continuing need for soil conservation. The GLASOD survey also enables comparisons to be drawn between degraded soils of different continents, and the methodology used can be a basis upon which plans for restoration of degraded lands can be based. 相似文献
42.
Animal farms are recognized as a major contributor to environmental pollution with antibiotic resistance genes, the persistence
at the source and the discharge routes to the environment of which need better understanding. The presence of 16 tetracycline
resistance genes (TRG) was assessed in feed, feces, manure lagoons, and the vicinities of three Georgia swine farms varied
on antibiotic usage and other operational characteristics. In these farms, TRG profiles of feces and lagoons were composed
of the same “persistent” and “transient” genes, with the former consistently observed in farms’ proximities and the latter
quickly attenuated in the lagoons. Fourteen TRG incidents, 13 of which occurred in gullies, ponds, and creeks, were detected
around farms. Their frequency correlated to the cumulative antibiotic usage (R
2 = 0.99), number of lagoons (R
2 = 0.73), and precipitation (R
2 = 0.83), but not to the size of herd or the amount of manure used for fertilization. Gene-specific amplicons of TRG from
the farms’ proximities were similar to those of “persistent” TRG from corresponding farms. Our data suggested the independency
of TRG profiles of antibiotic usage, variability in TRG persistence in manure lagoons, correlations between operational practices
and TRG incidence in farms’ vicinities, and spills and seepage from lagoons as TRG environmental routes. 相似文献
43.
44.
A 15-month-old, male neutered Staffordshire Bull Terrier cross was presented to its referring veterinarian collapsed and agonal. He was immediately intubated, manually ventilated, and treatment commenced for presumptive snake envenomation with two vials of Tiger/Multi-Brown Snake Antivenom (minimum 7000 units/vial). The dog was transferred to a referral hospital intubated. Additional diagnostics performed following arrival at the referral hospital included a urine snake venom detection kit test, which was positive for brown snake immunotype. Three additional vials of Tiger/Multi-Brown Snake Antivenom (minimum 7000 units/vial) were administered until the dog was extubated and able to stand. Venom-induced consumptive coagulopathy (VICC) was diagnosed based on prolonged clotting times and scleral haemorrhage. Paroxysms of right ventricular outflow tract (RVOT) origin ventricular arrhythmias were treated with lignocaine and sotalol. Four days after presentation, a new-grade IV/VI systolic heart murmur was auscultated, prompting an echocardiogram. An anechoic and compartmentalised mass measuring 43 mm × 19 mm was visualized within the right ventricular wall at the RVOT, immediately adjacent to the pulmonic valve. The mass was causing a RVOT obstruction. Its appearance was suggestive of an intramyocardial haematoma, most likely secondary to VICC. The dog remained cardiovascularly stable, and treatment consisted of supportive care. Recheck echocardiograms at 2 and 7 weeks after discharge revealed progressive improvement of the intramyocardial mass and resolution of the associated heart murmur. Although intramyocardial haematomas are rare, it should be considered as a differential in dogs that develop a newly diagnosed heart murmur and/or cardiac arrhythmia following brown snake envenomation. 相似文献
45.
M Boller K Kelers MA Stevenson KD Winkel S Hardjo J Heller PR Judge HM Ong AM Padula C Reddrop LCP Santos CR Sharp L Smart KL Swindells D Tabrett JR Wierenga 《Australian veterinary journal》2020,98(9):442-448
SnakeMap is a national cloud-based, veterinary snakebite registry. It was designed to prospectively collect data of the clinical circumstances and temporospatial information on cases of snake envenomation in dogs and cats. We herein introduce the project and summarise the data from the first 4 years of SnakeMap. The registry is a veterinary community-based online database allowing case entry from veterinary hospitals across Australia. Registry data comprise hospital characteristics, patient characteristics, envenoming snake type, treatment and outcome variables, including time and geolocation of the snake bite. We present summative information on select key variables from the SnakeMap registry (1 July 2015 to 30 June 2019). Twenty-eight hospitals from 6 states/territories entered 624 cases into the registry, including 419 dogs (67%) and 205 cats (33%). Bite time was available in 216 animals of which 90 (42%) were reported to be bitten in the 3 hours between 03:00 pm and 05:59 pm; median bite to presentation interval was 60 (interquartile range [IQR] 30, 211) minutes in dogs and 95 (IQR 41, 238) minutes in cats. Bites occurred in the owner's yard in 356 dogs (85%) and 53 cats (26%). A snake venom detection kit was used in 172 cases (28%) and antivenom was administered in 523 cases (85%). Most animals (n = 534, 88%) survived to discharge (median hospitalisation of 25 [IQR 16, 62] hours). SnakeMap effectively collects relevant clinical data from dogs and cats with presumed snake bite and provides locally specific information on the epidemiology of snake envenomation in small animals. 相似文献
46.
Contrasting patterns of variation in weedy traits and unique crop features in divergent populations of US weedy rice (Oryza sativa sp.) in Arkansas and California
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47.
48.
Effects of Growth Hormone on In Situ Culture of Bovine Preantral Follicles are Dose Dependent
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CR Jimenez JL de Azevedo RG Silveira J Penitente‐Filho EL Carrascal‐Triana AM Zolini VR Araújo CAA Torres 《Reproduction in domestic animals》2016,51(4):575-584
The objective of this study was to evaluate different concentrations of growth hormone (GH) on the development of bovine preantral follicles cultured included in the ovarian tissue (in situ) on the rates of morphologically normal, viable, primordial and developing follicles, as well as the oocyte and follicle diameter and ultrastructural analysis. Ovarian fragments collected from cows with no cross‐breeds defined were cultured in situ for 1 and 7 days in minimal essential medium (α‐MEM+) supplemented with different concentrations of recombinant human GH (0, 10, 25, 50 ng/ml). The ovarian fragments non‐cultured (control) and cultured were processed for classic histology, mechanical isolation and electron transmission microscopy (MET). The parameters underwent anova (Tukey′s and Dunnett′s tests) and chi‐square test (χ2). After 7 days of culture, the treatment with 50 ng/ml GH showed no differences with fresh control (p > 0.05) and had greater effectiveness than in the 0, 10 and 25 ng/ml GH concentrations of the morphologically normal follicles. Regarding the primordial follicles, a reduction was observed in the 50 ng/ml GH concentration concomitant with the significant increase in developing follicles, differing from both the fresh control and the other GH concentrations tested. In addition, 50 ng/ml GH showed a larger follicle and oocyte diameter when compared to the other treatments cultured. Similar structures were ultrastructurally observed in the control group, 50 ng/ml GH. Follicles cultured in 10 ng/ml GH showed nuclear invagination, vacuoles and lesioned basal membrane. Hence, it is concluded that 50 ng/ml GH is the most effective concentration for the development of preantral follicles cultured in situ. 相似文献
49.
AA Stewart LR Goodrich CR Byron RB Evans MC Stewart 《Australian veterinary journal》2010,88(4):115-123
Objective To present the technique for intra-articular catheter placement and report the clinical outcomes of 38 cases of equine synovial trauma and/or infection treated with broad-spectrum antimicrobials administered via an intrasynovial catheter (ISC). Design Retrospective study. Procedure Medical records of 38 horses treated for synovial trauma and sepsis with frequent antimicrobial administration through an ISC from 1995 to 2008 were reviewed. Follow-up information was obtained via clinical re-evaluation or telephone contact with the owners. Results The majority of horses (84%) received amikacin and Timentin® four times daily. In addition, synovial lavage through the ISC was carried out in 27 horses (71%). Only radiological evidence of osteolysis had a significant negative impact on both lameness at the time of hospital discharge and the long-term outcome. In total, 92% of horses treated with frequent antimicrobial administration through an ISC had clinical resolution of infection. Catheter obstruction occurred in three cases, necessitating replacement or removal, and two synovial fistulae developed at sites of open drainage. The majority of horses treated had a favourable outcome, with 86% being at least pasture sound and 43% returned to riding. Conclusion Septic synovial structures treated with frequent antimicrobial administration through an ISC had a good prognosis for survival and 43% returned to riding, which is consistent with the results of other studies. The use of a simple ISC should be considered when broad-spectrum intrasynovial antimicrobial administration and lavage of a septic synovial structure are indicated. 相似文献
50.
AA da Rocha ICN da Cunha BB Ederli AP Albernaz CR Quirino 《Reproduction in domestic animals》2009,44(S2):313-315
Polyunsaturated fatty acids are important membrane components that influence membrane integrity and fluidity. In the present study, the effect of oral supplementation for 60 days with essential fatty acids (omega 3, 6 and 9) and vitamin E on canine semen quality was evaluated. Sixteen dogs were selected for the experiment; eight were used as the control group and eight received the fatty acid supplemented diet for 60 days. Semen samples were taken every 15 days during the entire experimental period and were analyzed for volume (ml), motility (%), vigour (0–5), concentration (×106 /ml), morphology of spermatozoa (%), plasma membrane integrity (%; using the hyposmotic swelling test) and thermoresistance (motility and vigour after 4 h at 38°C). We concluded that, daily supplementation with omega 3, omega 6 and omega 9 fatty acids, together with vitamin E, for a period of 60 days, significantly increased the semen volume of the treated group after 15 days of supplementation; the vigour and concentration of spermatozoa were superior after the first month of supplementation, while the percentage of morphologically abnormal spermatozoa decreased and the cells were protected against thermal stress. 相似文献