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51.
CASE HISTORY: An adult female Duvaucel's gecko (Hoplodactylus duvaucelii) from a threatened species breeding programme presented due to a prolonged gestation period and distended abdomen.

CLINICAL AND PATHOLOGICAL FINDINGS: The gecko was in lean body condition with an irregularly shaped, firm mass in the coelomic cavity. Radiographically there was a diffuse radio-opacity within the coelomic cavity with cranial displacement of the right lung field. Ultrasonography revealed a round homogenous abdominal mass of medium echogenicity with an echogenic capsule. Haematology showed a leucocytosis with a moderate left shift in heterophils and toxic changes. Bilateral ovariectomy was performed to remove two ovarian granulomas and Salmonella enterica subspecies houtenae (IV) was cultured from the ovarian tissue. The gecko recovered well from the surgery, regained weight and remained in good health 3 years following the surgery.

DIAGNOSIS: Pre-ovulatory stasis and ovarian granulomas associated with infection with Salmonella enterica subsp. houtenae.

CLINICAL RELEVANCE: The surgery described in this case resulted in recovery of the gecko, which despite its loss of reproductive capability is of value as an education animal. This is the first report of pre-ovulatory stasis and ovarian granulomas associated with infection with Salmonella enterica in a Duvaucel's gecko and is also the first reported case of pre-ovulatory stasis in a viviparous lizard species. The case adds to knowledge regarding potential reproductive pathology in lizards, which is particularly important information for managers of captive lizard breeding programmes.  相似文献   
52.
Mice infected with Trypanosoma congolense developed a severe anaemia 1 week after infection, which persisted till treatment with diminazine aceturate when the packed cell volume (PCV) recovered to pre-infection levels. This was accompanied by a marked increase in the plasma levels of the acute phase proteins (APP), serum amyloid P-component (SAP) and haptoglobin (Hp). The initial peak levels of Hp and SAP were attained 7 and 12 days post-infection (DPI), respectively. Thereafter SAP levels decreased significantly to near pre-infection levels, but later increased even after treatment to give a second peak 34 DPI after which there was a decline till the study was terminated. The Hp levels on the other hand decreased to an intermediate level after the initial peak increasing to a second peak 22 DPI. Thereafter Hp decreased significantly following diminazine aceturate treatment to reach pre-infection levels within 5 days post-treatment. This indicates that T. congolense-infected mice develop severe anaemia accompanied by an acute phase response leading to an increase in SAP and Hp but that following treatment divergent responses occurred indicating differences in the pathways for stimulation of the APP. Haptoglobin was shown to be an earlier indicator of infection and a better marker in monitoring the response to treatment.  相似文献   
53.
Early pregnancy diagnosis and monitoring play an important role following embryo transfer in sheep. The aims of the current study were to investigate (i) the pattern of serum progesterone profiles in sheep carrying somatic cell nuclear transfer (SCNT)‐derived (clone) pregnancies, and (ii) the frequency of pregnancy loss during development following SCNT embryo transfer. Sheep SCNT embryos were made using standard nuclear transfer techniques. Day 7 embryos were surgically transferred to oestrus‐synchronized recipients (n = 27). As a control, normal fertile ewes (n = 12) were bred by natural breeding. Serum was collected from all the ewes on the day of estrus (day 0 sample), 7 days post‐estrus (day 7 sample) and 19 days post‐estrus (day 19 sample) and every 10 days thereafter until lambing or pregnancy loss occurred. Serum progesterone (P4) was assessed using enzyme immunoassay. Pregnancy was confirmed by ultrasound scanning on day 35 of pregnancy followed by subsequent scanning every 10 days. In control ewes, pregnancy rate on day 35 was 83.3% (10/12), whereas in the ewes that received SCNT embryos, it was 22.2% (6/27; p < 0.05). The day 45 pregnancy rate in the control ewes was 83.3%, whereas in the SCNT embryo recipients it was 11.0% (p < 0.05). Hormone analysis revealed that SCNT embryo recipients exhibited a significantly lower P4 profiles at different time points in pregnancy compared to controls (p < 0.05). This study highlights the use of serum progesterone in combination with ultrasound for the investigation of embryo loss and crucial times during development of normal and SCNT embryos in sheep. Further, the serum P4 levels directly reflect the degree of placental development in these two groups.  相似文献   
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55.
Field studies were conducted in 2007 and 2008 in North Carolina to determine the response of the weed Maryland meadowbeauty and blueberry to flumioxazin PRE (pre-emergence). No injury to non-bearing (blueberry plants not mature enough to produce fruit) or bearing (blueberry plants mature enough to produce fruit) blueberry from flumioxazin PRE was observed. In non-bearing blueberry, control of meadowbeauty was greater than 97% 90 DAT (days after treatment) with the registered rate of 0.42 kg ai ha–1 flumioxazin. Across two studies in bearing blueberry, a single application of flumioxazin at 0.42 kg ai ha–1 controlled meadowbeauty 79% to 92% 90 DAT. Flumioxazin at 0.21 kg ai ha–1 applied twice 60 d apart resulted in greater than 96% meadowbeauty control 90 d after the first application. Treatments of flumioxazin applied as a single application or two applications applied sequentially 60 d apart in bearing blueberry had yields ranging from 3150 to 6065 kg ha–1and 3551 to 5735 kg ha–1, respectively, and did not have a negative effect on blueberry yield regardless of application rate compared to the nontreated check.  相似文献   
56.
The effects of maturity on grain quality and wet‐milling properties were investigated for two hybrids of corn. Significant differences for hybrid and maturity were observed for all grain quality parameters. Test weight, absolute density, and thousand‐grain weight all increased as the corn matured. Kernel hardness increased and breakage susceptibility varied with increased maturity. Water uptake parameters decreased with maturity of the grain. The starch yield results from wet milling showed that the starch yield increased significantly within each cultivar in the early stages of grain maturity, but there were no significant differences between hybrids. Mathematical models using selected grain quality parameters accurately predicted trends in starch yield for the immature and mature corn samples in this study.  相似文献   
57.
Reconciling food security, economic development and biodiversity conservation is a key challenge, especially in the face of the demographic transition characterizing many countries in the world. Fisheries and marine ecosystems constitute a difficult application of this bio‐economic challenge. Many experts and scientists advocate an ecosystem approach to manage marine socio‐ecosystems for their sustainability and resilience. However, the ways by which to operationalize ecosystem‐based fisheries management (EBFM) remain poorly specified. We propose a specific methodological framework—viability modelling—to do so. We show how viability modelling can be applied using four contrasted case‐studies: two small‐scale fisheries in South America and Pacific and two larger‐scale fisheries in Europe and Australia. The four fisheries are analysed using the same modelling framework, structured around a set of common methods, indicators and scenarios. The calibrated models are dynamic, multispecies and multifleet and account for various sources of uncertainty. A multicriteria evaluation is used to assess the scenarios’ outcomes over a long time horizon with different constraints based on ecological, social and economic reference points. Results show to what extent the bio‐economic and ecosystem risks associated with the adoption of status quo strategies are relatively high and challenge the implementation of EBFM. In contrast, strategies called ecoviability or co‐viability strategies, that aim at satisfying the viability constraints, reduce significantly these ecological and economic risks and promote EBFM. The gains associated with those ecoviability strategies, however, decrease with the intensity of regulations imposed on these fisheries.  相似文献   
58.
Chitosan nanofiber membranes are recognized as functional antimicrobial materials, as they can effectively provide a barrier that guides tissue growth and supports healing. Methods to stabilize nanofibers in aqueous solutions include acylation with fatty acids. Modification with fatty acids that also have antimicrobial and biofilm-resistant properties may be particularly beneficial in tissue regeneration applications. This study investigated the ability to customize the fatty acid attachment by acyl chlorides to include antimicrobial 2-decenoic acid. Synthesis of 2-decenoyl chloride was followed by acylation of electrospun chitosan membranes in pyridine. Physicochemical properties were characterized through scanning electron microscopy, FTIR, contact angle, and thermogravimetric analysis. The ability of membranes to resist biofilm formation by S. aureus and P. aeruginosa was evaluated by direct inoculation. Cytocompatibility was evaluated by adding membranes to cultures of NIH3T3 fibroblast cells. Acylation with chlorides stabilized nanofibers in aqueous media without significant swelling of fibers and increased hydrophobicity of the membranes. Acyl-modified membranes reduced both S. aureus and P. aeruginosa bacterial biofilm formation on membrane while also supporting fibroblast growth. Acylated chitosan membranes may be useful as wound dressings, guided regeneration scaffolds, local drug delivery, or filtration.  相似文献   
59.
The establishment of no‐take marine reserves has been increasingly promoted as a key measure to achieve conservation and sustainability goals in fisheries. Regardless of the wide range of benefits cited, the effectiveness of reserve establishment depends critically on fisheries management outside the reserves. We construct a bioeconomic model of a fishery that allows for the establishment of a no‐take marine reserve and evaluate how the choice of the off‐reserve management target influences the effectiveness of reserve establishment. We evaluate two biomass targets: (i) BMSY or the biomass that produces the maximum sustainable yield (MSY) and (ii) BMEY or the biomass that maximizes the net present value of the returns to fishing. The parameterized model shows that, for a wide range of scenarios, the fishery will be better off in terms of both conservation and economic objectives when the no‐take reserve is established in conjunction with the BMEY target rather than with the BMSY target. Model results further show that the opportunity cost of securing additional fish biomass, in both deterministic and stochastic environments, is lower when the reserve size is increased under the BMEY target. This finding is important because marine reserves have been established as a key measure to restore depleted fish stocks, and the results suggest that this objective can be achieved with lower economic costs in a BMEY managed fishery.  相似文献   
60.
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