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101.
Mapping of lacustrine aquaculture and socio‐economic assessment of cage farmers operations can be employed as decision support tools in an integrated fashion for fisheries management. We simultaneously mapped and reported the location of cages and characterized socio‐economic and indicators of cage farming in Lake Victoria, Kenya. Structured questionnaires and interviews from cage farmers generated socio‐economic data and management information. Vital water quality parameters were analyzed in selected sampling sites. Cage culture was found to be a male‐dominated activity with the majority of owners aged <45 years (n = 23; 59%). Siaya County had the highest cage establishments (n = 20) and number (n = 1,343). Proximity to Dominion Farm, pioneers of cage culture, as well as decreased presence of water hyacinth (Eichhornia crassipes) coverage may have contributed to high cage numbers in Siaya County. The only species cultured was Oreochromis niloticus. Most cage establishments (n = 30; 76%) were located within 200 m from the shoreline. Total operational costs for a cycle (8 months) amounted to USD 465,250 worth a total production value of USD 8,827,000, farmers often realizing a mark‐up of >100%, indicative of its robust viability within “The Blue Economy” concept. With the increasing number of cages in the lake, there is the need for policy and regulations to guide its investment, both to protect local economies through improved business practices and to ensure sustainability for the lake ecosystem due to the likelihood of exacerbation in water quality deterioration in cage culture sites.  相似文献   
102.
A meningeal osteosarcoma was diagnosed in a dog displaying neurologic signs compatible with a space-occupying cerebellar lesion. Gross lesions, restricted to the brain, consisted of a solitary, compressive mass attached to the dura mater overlying the left cerebellum. The mass was composed of single and multinucleated, atypical polygonal cells that lined or rested within lacuna surrounded by eosinophilic, mineralized matrix. The matrical component stained dark green-yellow to blue with Movat's pentachrome stain, deep blue to red with Heidenhain aniline blue stain, and brown-black with Von Kossa stain. Results of these stains were interpreted as tumor osteoid. Foci of dural mineralization and osseous metaplasia were present at the point of tumor attachment. The microscopic observations were interpreted as an osteosarcoma of extraskeletal origin. To our knowledge, these findings represent the first documented case of a meningeal osteosarcoma in a domestic animal species.  相似文献   
103.
Saphenous nerve biopsy was performed to diagnose globoid cell leukodystrophy in a 3-month-old West Highland White Terrier. The dog had progressive neurologic disease that appeared to involve the cerebellum, spinal cord, and lower motor neurons to the hind limbs. Light and transmission electron microscopic findings of the nerve biopsy specimen established the diagnosis. Peripheral nerve biopsy may provide a reliable antemortem method for diagnosis of globoid cell leukodystrophy.  相似文献   
104.
Zinc deficiency was diagnosed in 2 flocks of sheep and a herd of goats. Alopecia and eating of wool were observed. Skin lesions were hyperkeratosis and parakeratosis. Abnormal hoof growth and a closed stance with arched back and bowed hindlimbs were seen. Anorexia, depression, and foot soreness diminished quickly after zinc supplementation. Skin lesions healed and hair and wool growth resumed. A cause for the deficiency could not be established.  相似文献   
105.
Erythrocytes from pigs with experimental porcine eperythrozoonosis were examined using light microscopy and scanning and transmission electron microscopy. Three distinct forms of Eperythrozoon suis were attached to the plasma surface of erythrocyte membrane. Erythrocytes were initially parasitized by one or several immature forms. Immature forms enlarged and developed into juvenile and mature forms. The parasite replicated by budding of small immature forms from larger immature forms, juvenile forms, and mature forms. Small immature forms attached to adjacent membrane of the same erythrocyte or a nonparasitized erythrocyte. E. suis organisms were intimately associated with, but distinctly separated from erythrocyte membrane by a 30-nm electron lucent zone. Cell membrane in this area was denser than adjacent nonparasitized membrane. Early interaction between erythrocyte membrane and small immature forms resulted in no membrane deformation, but as this form enlarged, it later became embedded in a deep cup-like membrane invagination. As the immature form developed into the juvenile form a shallow, broad-based depression was observed in the membrane. A similar depression that covered a greater surface area was observed in the membrane parasitized by the mature form. The interaction between the parasitic forms and erythrocyte membrane resulted ultimately in severe membrane deformation. Parasite-membrane interactions may play an important role in the development of misdirected immune responses in experimental porcine eperythrozoonosis.  相似文献   
106.
Incidents of human–wildlife conflict can solidify participant perspectives and expectations, and reveal underlying social and institutional dynamics. We describe and analyze two incidents of conflict between hunters and grizzly bears in 2011 and 2012. Both incidents were associated with the controversial elk hunt in Grand Teton National Park, Wyoming. We gathered quotes from opinion-editorials and interviews, categorized quotes according to type, and used cluster analysis to identify discourses and associated coalitions of participants. We examined how participants defined problems, used evidence, and advocated solutions in relation to these incidents. Participant discourses addressed technical and procedural issues of regional wildlife management that extended beyond these incidents, revealing divergent expectations about wildlife management on public lands. Existing decision-making processes dominated by government agencies do not appear to be addressing these expectations. We recommend an integrative, outside appraisal of regional elk management to address conflict and support ecologically sound decision-making that serves common interests.  相似文献   
107.
In a 10-year period, extramedullary plasmacytomas (EMP) represented 5.2% of all oral tumors found in the dog (16/302). These 16 oral EMP comprised 28.5% of all EMP within the same time period. Eleven dogs died with a median survival time of 474 days. Five dogs remain alive at the time of this writing. Dogs without complete surgical removal of the EMP and no adjuvant therapy had a median survival time of 138 days. Oral EMP have a clinical behavior consistent with EMP arising from other tissues. They have no obvious correlation with multiple myeloma, and complete surgical resection may be curative.  相似文献   
108.

Purpose

To survey commonly used, sterile ophthalmic viscoelastic materials used during routine cataract surgery for the presence of bacterial DNA and/or viable bacteria and endotoxin quantification.

Methods

Samples from three different ophthalmic viscoelastic manufacturers and three different production lots per manufacturer were collected for 16 S ribosomal ribonucleic acid (rRNA) sequencing and conventional aerobic and capnophilic bacterial culture. Other samples of viscoelastic material from the same three manufacturers were collected for endotoxin quantification using a commercially available Limulus amebocyte lysate (LAL) assay. Statistical analysis was performed using Sigma Plot 14.0, and R v4.0.2.0. Differences (p ≤ .05) between sample collection sites in total DNA concentration, microbial richness, mean intra-group distances, and endotoxin quantification alongside reagent controls were evaluated.

Results

Culture yielded two isolates, identified as Staphylococcus epidermidis and Bacillus megaterium. 16 S rRNA sequencing revealed no differences between brands in richness or overall composition. The most common bacterial DNA detected across all brands was Staphylococcus sp., Cutibacterium sp., Flavobacterium sp., and Lactobacillus sp. A significant difference was found between the median endotoxin concentration between Anvision and Hyvisc® viscoelastic (Anvision: 0.171 EU/mL, Hyvisc®: 0.03 EU/mL; p < .001).

Conclusions

No brand-specific differences in bacterial DNA were detected in the viscoelastic materials. Staphylococcus, Cutibacterium, Flavobacterium, and Lactobacillus were the dominant contributors to the bacterial DNA detected. Although Anvision viscoelastic samples contained significantly more endotoxin than Hyvisc® viscoelastic samples, endotoxin concentrations were below the FDA limit of 0.2 EU/mL for both manufacturers. These data further the understanding of inflammatory outcomes following cataract surgery.  相似文献   
109.
Despite the development of several recent PCR assays for the egg stages of various trichostrongyles, there have been no protocols described for preserving field samples for PCR without refrigeration. In this study, Lugol's iodine (LI), sodium azide (SA), and neutral buffered formalin (NBF) were evaluated using Haemonchus contortus eggs to determine their potential as a preservative for trichostrongyle egg samples to be processed with real-time PCR. When egg recovery, embryo development, and egg morphology were evaluated from fecal samples preserved with LI, NBF, and SA, there was equally good recovery and preservation for the first month. Preserved eggs were detectable for 1 month, but after 6 months, none could be recovered. When real-time PCR analysis was performed on eggs isolated from faeces preserved with LI and SA, there was no detectable inhibition compared to fresh, non-preserved eggs; however, NBF significantly inhibited amplification. The results from this study demonstrate that for PCR applications LI and SA are effective preservatives for H. contortus eggs, resulting in good preservation of morphology while allowing for uninhibited PCR.  相似文献   
110.
The enteric pathogen Salmonella enterica serovar Typhimurium causes food poisoning resulting in gastroenteritis. The S. Typhimurium effector Salmonella invasion protein A (SipA) promotes gastroenteritis by functional motifs that trigger either mechanisms of inflammation or bacterial entry. During infection of intestinal epithelial cells, SipA was found to be responsible for the early activation of caspase-3, an enzyme that is required for SipA cleavage at a specific recognition motif that divided the protein into its two functional domains and activated SipA in a manner necessary for pathogenicity. Other caspase-3 cleavage sites identified in S. Typhimurium appeared to be restricted to secreted effector proteins, which indicates that this may be a general strategy used by this pathogen for processing of its secreted effectors.  相似文献   
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