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991.
Little Salt Spring in southwest Florida, consisting of a shallow, water-filled basin above a deep, vertical underwater cavern, was a freshwater cenote in the peninsula's drier past. It collected and preserved perishable organic artifacts and other evidence of Paleo-Indian and Archaic Indian origin ranging in age from 12,000 to 9000 and from 6800 to 5200 years ago. An Archaic Period cemetery containing an estimated 1000 burials occupies an adjoining muck-filled slough and presently drowned portions of the basin of the spring. Artifacts and the nature of interment suggest a cultural link between the Archaic people and the much later Glades Tradition of southern Florida.  相似文献   
992.
A 2‐year‐old Holstein cow presented with a history of colic signs of 3 days’ duration that had not responded to routine medical therapy. Physical examination findings were consistent with tachycardia and colic. Ultrasonographic examination of the abomasum revealed a thin hyperechoic line producing a cone shadow. Radiography of the cranial abdomen revealed two radiopaque objects within the abomasum. Right paracostal laparotomy and abomasotomy permitted palpation and manual removal of two metallic foreign bodies and a small quantity of gravel. The animal recovered well after surgery and no signs of colic were observed. Her appetite and rumination were also improved.  相似文献   
993.
An in vivo trial was conducted in sheep to investigate the effect of three tropical tannin‐rich plants (TRP) on methane emission, intake and digestibility. The TRP used were leaves of Glyricidia sepium, Leucaena leucocephala and Manihot esculenta that contained, respectively, 39, 75 and 92 g condensed tannins/kg DM. Methane was determined with the sulphur hexafluoride tracer technique. Eight rumen‐cannulated sheep of two breeds (four Texel, four Blackbelly) were used in two 4 × 4 Latin square designs. Four experimental diets were tested. They consisted in a tropical natural grassland hay based on Dichanthium spp. fed alone (C) or in association with G. sepium (G), L. leucocephala (L) or M. esculenta (M) given as pellets at 44% of the daily ration. Daily organic matter intake was higher in TRP diets (686, 984, 1054 and 1186 g/day for C, G, L and M respectively; p < 0.05) while apparent organic matter total tract digestibility was not affected (69.9%, 62.8%, 65.3% and 64.7% for C, G, L and M respectively; p > 0.05). Methane emission was 47.1, 44.9, 33.3 and 33.5 g/kg digestible organic matter intake for C, G, L and M, respectively, and was significantly lower (p < 0.05) for L and M than for G and C. Our results confirm the potential of some TRP to reduce methane production. The strong decrease in methane and the increase in intake with TRPs may be due to their presentation as pellets.  相似文献   
994.
995.
An 8-yr-old male meerkat (Suricata suricatta) presented with sudden lethargy. A globular-shaped heart associated with pleural effusion on chest thoracic radiographs was consistent with congestive heart failure, and echocardiography was performed under general anesthesia. It revealed an Ebstein anomaly, with mild pericardial effusion and marked right heart enlargement. The animal was treated with imidapril chlorydrate. After 4 mo of treatment, thoracic radiographs still showed right-sided cardiomegaly; however, the animal appeared clinically normal.  相似文献   
996.
Seventy male lambs over 10 weeks of age were castrated using Burdizzo, rubber rings, or surgery to assess the acute and long-term effects of castration. All castrations were performed under local anaesthesia. The surgically castrated lambs were additionally sedated with xylazine and the sedation reversed with tolazoline. The frequency of abnormal postures and immediate behavioural responses indicated that surgically castrated lambs were most distressed; the lambs castrated using Burdizzo and rubber rings were not dissimilar to those of the control group. Between 1.5 and 9 h after castration, signs of pain and distress were at a lower level in lambs anaesthetised with bupivacaine compared with those treated with lidocaine. Due to the markedly faster wound healing, Burdizzo castration seemed to be preferable (fewer signs of long-term pain) when compared to the rubber ring technique. It was concluded that local anaesthesia with bupivacaine, followed by the Burdizzo method is the preferable technique for the castration of lambs older than 10 weeks of age.  相似文献   
997.
Histology is often taught in higher education settings using online virtual microscopes (VM). This study aimed to develop and evaluate the use of VM in teaching on a BSc degree at the University of Nottingham by surveying students and staff. A key development was the use of an e-workbook so that students were actively engaged in creating their own bespoke revision material. Subsequently, this approach was used in a second study evaluating the use of VM in teaching the histology and pathology of the gastrointestinal (GI) tract via group work with students from two BSc courses at the University of Nottingham; one based at Derby (RDHC) and the other in Malaysia (UNMC). Students worked together in groups to complete an e-workbook, develop a presentation, and decide how to collaborate and communicate. An evaluation of these activities revealed advantages in developing transferrable skills, and good engagement with both the histology topic and group work. Analysis of assessment of the module at UNMC showed that student performance improved in the histology-based module after the intervention (p < 0.01) and that this improvement was not evident in other modules taken by the cohort. Furthermore, when interrogating the questions from the examination paper that asked students to identify features from histological images, fewer questions were seen as ‘difficult’ (p < 0.001) and more were seen as ‘average’ (p < 0.01). This study demonstrates that the use of VM in histology combined with active learning in creating a revision resource enhances engagement and depth of learning. When further combined with collaborative active group work, students developed a range of histology knowledge and transferrable skills, with notable improvement in examination performance relative to other contemporaneous modules.  相似文献   
998.
Neoplasia of the tubular genital tract in goats, while rarely described, is most commonly reported as uterine adenocarcinoma, leiomyoma, or leiomyosarcoma. In this retrospective, single-center, case series, medical records were searched for goats with a computed tomography (CT) diagnosis of tubular genital mass and a definitive histologic (surgical biopsy or necropsy) diagnosis of malignant neoplasia. Data recorded from CT images were presence of peritoneal/retroperitoneal fluid, urinary tract obstruction, abdominal lymphadenomegaly, additional abdominal nodules/masses, and pulmonary nodules. For masses, maximum cross-sectional area, contrast enhancement, and uterine luminal fluid accumulation were also recorded. Seven goats met the inclusion criteria (leiomyosarcoma n = 5, adenocarcinoma n = 2). Both goats with adenocarcinoma had upper urinary tract obstruction, moderate to severe regional lymphadenopathy, peritoneal fluid, and peritoneal or hepatic nodules/masses; one goat with adenocarcinoma was discharged and subsequently euthanized, and the other had palliative mass debulking and was lost to follow up. Goats with leiomyosarcoma had infrequent, mild peritoneal fluid and mild sublumbar lymphadenopathy. Of the goats with leiomyosarcoma, two were euthanized at or near the time of CT imaging, two were euthanized at the time of surgery due to perceived mass non-resectability, and one had mass regression approximately four months post ovariohysterectomy but was subsequently lost to follow up. Five goats had pulmonary nodules, three of which had pathologic confirmation (pulmonary metastasis in a single patient with adenocarcinoma, and lungworm granulomas in two goats with leiomyosarcoma). Severe sublumbar lymphadenopathy and obstructive uropathy were sequelae in the two caprine patients with genital adenocarcinoma, and in none with leiomyosarcoma.  相似文献   
999.

BACKGROUND

Pesticides are considered main contributors to global arthropod declines and therefore may decrease the provision of ecosystem services such as natural pest control. Organic farming and cultivating pest- and disease-resistant varieties can allow pesticide applications and their impacts on nontarget organisms and the environment to be reduced. We investigated the effects of organic versus conventional management and fungus-resistant versus susceptible wine grape varieties on arthropod biodiversity and pest control of grape berry moths in 32 vineyards in the Palatinate region, Germany. Hazard quotients of applied pesticides were calculated for each vineyard.

RESULTS

The cultivation of fungus-resistant varieties led to significantly reduced hazard quotients and in turn enhanced abundances of natural enemies, particularly theridiid and philodromid spiders. Unexpectedly, organic management resulted in higher hazard quotients than conventional management and reduced numbers of natural enemies, particularly earwigs. Pest predation rates showed no significant differences between grape varieties or management types.

CONCLUSION

Widespread benefits of organic management on arthropod biodiversity found in other crops were absent in our viticultural study region. This is likely due to the dominant role of fungal diseases in viticulture, which requires high numbers of fungicide treatments under both conventional and organic viticulture. Thus, fungicide reduction through the cultivation of fungus-resistant grape varieties is one key element to fostering the abundance of arthropods in general and beneficial arthropods in particular. Beyond vineyards, this is potentially relevant in numerous other crop types. © 2023 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.  相似文献   
1000.
Data on the prevalence of antimicrobial resistant enterococci and staphylococci from the poultry production environment are sparse in the United States. This information is needed for science-based risk assessments of antimicrobial use in animal husbandry and potential public-health consequences. In this study, we assessed the susceptibility of staphylococci and enterococci isolated from poultry litter, recovered from 24 farms across Georgia, to several antimicrobials of veterinary and human health importance. Among the 90 Enterococcus isolates recovered, E. hirae (46%) was the most frequently encountered species, followed by E. faecium (27%), E. gallinarum (12%), and E. faecalis (10%). Antimicrobial resistance was most often observed to tetracycline (96%), followed by clindamycin (90%), quinupristin-dalfopristin (62%), penicillin (53%), erythromycin (50%), nitrofurantoin (49%), and clarithromycin (48%). Among the 110 staphylococci isolates recovered, only coagulase-negative staphylococci (CNS) were identified with the predominant Staphylococcus species being S. sciuri (38%), S. lentus (21%), S. xylosus (14%) and S. simulans (12%). Resistance was less-frequently observed among the Staphylococcus isolates for the majority of antimicrobials tested, as compared with Enterococcus isolates, and was primarily limited to clarithromycin (71%), erythromycin (71%), clindamycin (48%), and tetracycline (38%). Multidrug resistance (MDR) phenotypes were prevalent in both Enterococcus and Staphylococcus; however, Enterococcus exhibited a statistically significant difference in the median number of antimicrobials to which resistance was observed (median = 5.0) compared with Staphylococcus species (median = 3.0). Because resistance to several of these antimicrobials in gram-positive bacteria may be attributed to the shuttling of common drug-resistance genes, we also determined which common antimicrobial-resistance genes were present in both enterococci and staphylococci. The antimicrobial resistance genes vat(D) and erm(B) were present in enterococci, vgaB in staphylococci, and mobile genetic elements Tn916 and pheromone-inducible plasmids were only identified in enterococci. These data suggest that the disparity in antimicrobial-resistance phenotypes and genotypes between enterococci and staphylococci isolated from the same environment is, in part, because of barriers preventing exchange of mobile DNA elements.  相似文献   
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