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51.
Hannah R. Leventhal Anna M. Hassebroek Francisco Carvallo Harold C. McKenzie 《Journal of veterinary diagnostic investigation》2021,33(6):1123
A 14-y-old pony mare was referred after 30-d duration of intermittent pyrexia, anorexia, weight loss, and change in manure consistency. Physical examination revealed a palpable but reducible ventral abdominal mass. Transabdominal ultrasonography revealed multiple distended, hypomotile, and thickened small intestinal loops in close approximation with numerous, well-defined, hyperechoic masses. There was a large amount of echogenic peritoneal fluid; abdominocentesis revealed a neutrophilic and macrophagic inflammatory exudate, and a mixed bacterial population was cultured. Given the poor prognosis, the mare was euthanized. The autopsy findings included a large abdominal abscess, serosanguineous peritoneal fluid with fibrin strands, and ~50 outpouches communicating with the lumen and extending from the anti-mesenteric aspect of the duodenum, jejunum, and ileum. These structures were classified as pseudodiverticula based on the histologic absence of the tunica muscularis layer of the intestinal wall. Pseudodiverticula should be included as a differential etiology in horses when clinical signs consistent with colic, diarrhea, or weight loss are recognized and, when on examination, one or more organized masses are palpated or visualized on transabdominal ultrasound, as well as visualization of small intestinal loops with thickened walls. 相似文献
52.
Plant species richness and diversity in urban and peri-urban gardens of Niamey,Niger 总被引:1,自引:0,他引:1
Hannah Bernholt Katja Kehlenbeck Jens Gebauer Andreas Buerkert 《Agroforestry Systems》2009,77(3):159-179
Urban and peri-urban agriculture (UPA) significantly contributes to food and nutritional security of urban dwellers in many
African countries. Economic and demographic pressures often lead to transformation of subsistence-oriented traditional homegardens
into commercial production units. Such transformation is claimed to result in decreasing plant diversity, particularly of
local species. A study was therefore undertaken in 51 gardens of Niamey, Niger, to assess the factors determining plant diversity
and the suitability of UPA for in situ conservation of plant genetic resources. In each garden, the number and abundance of
all human-used plant species were determined, and species density, Shannon index and Shannon evenness were calculated. In
the 51 surveyed gardens, a total of 116 plant species were cultivated, most of them for the production of fruits or vegetables.
Annual vegetables dominated, particularly exotic species grown for sale. In the cold season, an average of 14 species were
cultivated per garden, the Shannon index was 0.96 and evenness was 0.39. Commercial gardens had a species richness similar
to that of subsistence gardens, but a lower evenness (P < 0.005), caused by the dominance of a few vegetable species. Gardens of immigrants had a lower Shannon index than those
of members of the local Djerma ethnic group. Stepwise multiple regression analysis showed significant influence of various
variables on plant species richness and diversity parameters: garden size (richness and Shannon index), ethnicity of the gardener
(richness and evenness), gender of the gardener and cash-oriented production (evenness), household size (richness) and garden
possession status (Shannon index). Cluster analysis revealed the existence of five garden types. The highest species richness
and diversity, particularly of perennial and local species, was found in large, peri-urban, commercial gardens managed by
relatively wealthy, elderly gardeners with large families and a regular non-agricultural income. 相似文献
53.
Evi Pecceu Brittainy Stebbing Yolanda Martinez Pereira Ian Handel Geoff Culshaw Hannah Hodgkiss-Geere Jessica Lawrence 《Veterinary research communications》2017,41(4):249-256
Vasovagal tonus index (VVTI) is an indirect measure of heart rate variability and may serve as a marker of disease severity. Higher heart rate variability has predicted lower tumour burden and improved survival in humans with various tumour types. The purpose of this pilot study was to evaluate VVTI as a biomarker of remission status in canine lymphoma. The primary hypothesis was that VVTI would be increased in dogs in remission compared to dogs out of remission. Twenty-seven dogs were prospectively enrolled if they had a diagnosis of intermediate to high-grade lymphoma and underwent multidrug chemotherapy. Serial electrocardiogram data were collected under standard conditions and relationships between VVTI, remission status and other clinical variables were evaluated. VVTI from dogs in remission (partial or complete) did not differ from dogs with fulminant lymphoma (naive or at time of relapse). Dogs in partial remission had higher VVTI than dogs in complete remission (p = 0.021). Higher baseline VVTI was associated with higher subsequent scores (p < 0.001). VVTI also correlated with anxiety level (p = 0.03). Based on this pilot study, VVTI did not hold any obvious promise as a useful clinical biomarker of remission status. Further investigation may better elucidate the clinical and prognostic utility of VVTI in dogs with lymphoma. 相似文献
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1. Many populations of sea‐ducks, which typically winter at sea but breed on fresh water, are declining. Numbers of common scoters Melanitta nigra (L.) breeding in Scotland halved between 1995 and 2007, despite most breeding sites having special conservation status. To identify potential conservation measures, a 3‐year study was conducted, investigating correlates of lake use by scoters. 2. At 26 scoter breeding lakes, food abundance (macroinvertebrates) and foraging habitats (substrates, water depth) were measured, and their associations with scoter lake use explored using multi‐model inference. Correlates of macroinvertebrate abundance (water quality, fish abundance) were also investigated. 3. Averaged over 3 years (2009–2011), these lakes held 26.7 (SE 6.3) females, around half the Scottish breeding population. Scoters occurred more often at lakes having abundant large‐bodied invertebrates and extensive shallow water. Lakes where the average weight of the largest invertebrate in each sample exceeded 4 mg had 9.2 times (females) or 27 times (broods) more scoter records than other lakes. Lakes where water depths (10 m from the shore) averaged less than 1.3 m had 2.5 times (females) or 12 times (broods) more scoter records than other lakes. 4. The abundance of large‐bodied invertebrates was greater where small fish species (mostly three‐spined sticklebacks Gasterosteus aculeatus) were more common and brown trout Salmo trutta were scarcer. 5. Results suggest two approaches to scoter conservation. At lakes used for hydro‐electricity generation, water level regimes that provide extensive shallow water should be tested to see if these benefit scoters. At lakes used for trout fishing, trout reduction by increased angling should be trialled, to see if this increases large‐invertebrate abundance and scoter use. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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59.
Carter RA Engiles JB Megee SO Senoo M Galantino-Homer HL 《Equine veterinary journal》2011,43(5):543-551
Reasons for performing study: Abnormal epidermal stem cell regulation may contribute to the pathogenesis of equine chronic laminitis. Objective: To analyse the involvement of p63, a regulator of epidermal stem cell proliferative potential, in chronic laminitis. Methods: Epidermal tissues from skin, coronet and lamellae of the dorsal foot were harvested from 5 horses with chronic laminitis and 5 control horses. Tissues were analysed using histopathology, immunofluorescence microscopy and quantitative immunoblotting Results: Hoof lamellae of laminitic horses had a lower frequency of p63 positive cells than control lamellae, particularly in the distal region. Quantitative immunoblotting confirmed reduced p63 expression in the laminitic distal lamellar region. The decreased p63 expression in laminitic epidermal lamellae was most apparent in the abaxial region adjacent to the hoof wall and highly associated with the formation of terminally differentiated, dysplastic and hyperkeratotic epidermis in this region, whereas lamellae from control horses maintained high p63 expression throughout the axial‐abaxial axis. Conclusions: Expression of p63 in equine skin resembles that reported in other species, including man and rodents, suggesting that p63 can serve as a marker for the proliferative potential of equine epidermal stem cells. p63 expression was significantly lower in the chronic laminitic hoof than in that of control horses, suggesting laminitic hoof epithelium has more limited proliferative potential with a shift towards differentiation. This may reflect reduced activity of epidermal stem cells in laminitic hoof. It is proposed that p63 contributes to the maintenance of hoof lamellae and that misregulation of p63 expression may lead to epidermal dysplasia during lamellar wedge formation. Potential relevance: This study suggests that loss of epidermal stem cells contributes to the pathogenesis of equine laminitis. Autologous transplantation of p63‐positive epidermal stem cells from unaffected regions may have regenerative therapeutic potential for laminitic horses. 相似文献
60.
Nils Dittbrenner Hannah Schmitt Yvan Capowiez Rita Triebskorn 《Journal of Soils and Sediments》2011,11(6):1000-1010