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991.
Aspergillosis is an infectious, non‐contagious fungal disease of clinical importance in flamingo collections. Itraconazole is an antifungal drug commonly used in the treatment and prophylaxis of avian aspergillosis. Studies have shown that dosage regimes in birds vary based on different itraconazole presentation and administration methods. This investigation used a population pharmacokinetic approach to study itraconazole in lesser flamingos. Itraconazole was administered orally at 10 mg/kg to 17 flamingos. A sparse blood sampling was performed on the subjects, and samples were collected at 1, 2, 3, 5, 8, 12, 16, 21, and 24 hr post‐drug administration. Twelve flamingos were sampled three times, three birds bled twice and two sampled once. Itraconazole in plasma was quantified using high‐pressure liquid chromatography (HPLC). A one‐compartment pharmacokinetic model with first order absorption was fitted to the data using nonlinear mixed effects modeling (NLME) to determine values for population parameters. We identified a long half‐life (T½) of more than 75 hr and a maximum plasma concentration (CMAX) of 1.69 µg/ml, which is above the minimal inhibitory concentrations for different aspergillus isolates. We concluded that plasma drug concentrations of itraconazole were maintained in a population of flamingos above 0.5 ug/ml for at least 24 hr after a single oral dose of 10 mg/kg of itraconazole solution.  相似文献   
992.

Nitrogen (N) plays an important role in small-scale dairy systems, both in production costs and as an indicator of environmental impact. The objective of this study was to quantify nitrogen inputs and outputs to identify areas for improvement in nitrogen utilisation efficiency (NUE). Evaluation was in 12 small-scale dairy farms with different feeding strategies. Six followed the traditional cut and carry of irrigated temperate pastures (CUT), and six have implemented grazing of pastures (GRZ), quantifying N inputs and outputs from May 2016 to April 2017. Data were analysed by ANOVA following a split-plot model with season (rainy or dry) as main plots and feeding strategy (CUT or GRZ) as split-plots, with results in kilograms N per hectare and kilograms N per cow. There were differences (P < 0.05) between seasons and strategies in N inputs from purchased N fertilisers and purchased feeds as concentrates and roughages, showing different N inputs and outputs whether in CUT or GRZ strategies. There were also significant interactions between seasons and strategies as in the sale of animals, where GRZ sell throughout the year, while CUT sell at the beginning of the dry season. N balance ranged from 33.9 to 183.0 kg N/ha, and 37.8 to 111.0 as kilograms N per cow with an interaction (P < 0.05) between season and strategies. There was a larger N surplus in GRZ during the rainy season from fertiliser inputs, which reduced N utilisation efficiency (NUE). Mean NUE in kilograms N per hectare and kilograms N per cow was 19%, with the higher efficiency for GRZ in the dry season. Farms with the best NUE had lower use of fertilisers and purchased feeds.

  相似文献   
993.
The aim of this work was to investigate the methylation and hydroxymethylation status of mesenchymal stem cells (MSC) from amniotic fluid (MSC‐AF), adipose tissue (MSC‐AT) and fibroblasts (FIB‐control) and to verify the effect of trichostatin A (TSA) on gene expression and development of cloned bovine embryos produced using these cells. Characterization of MSC from two animals (BOV1 and BOV2) was performed by flow cytometry, immunophenotyping and analysis of cellular differentiation genes expression. The cells were used in the nuclear transfer in the absence or presence of 50 nM TSA for 20 hr in embryo culture. Expression of HDAC1, HDAC3 and KAT2A genes was measured in embryos by qRT‐PCR. Methylation results showed difference between animals, with MSC from BOV2 demonstrating lower methylation rate than BOV1. Meanwhile, MSC‐AF were less hydroxymethylated for both animals. MSC‐AF from BOV2 produced 44.92 ± 8.88% of blastocysts when embryos were exposed to TSA and similar to embryo rate of MSC‐AT also treated with TSA (37.96 ± 15.80%). However, when methylation was lower in FIB compared to MSC, as found in BOV1, the use of TSA was not sufficient to increase embryo production. MSC‐AF embryos expressed less HDAC3 when treated with TSA, and expression of KAT2A was higher in embryos produced with all MSC and treated with TSA than embryos produced with FIB. The use of MSC less methylated and more hydroxymethylated in combination with embryo incubation with TSA can induce lower expression of HDAC3 and higher expression of KAT2A in the embryos and consequently improve bovine embryo production.  相似文献   
994.
The aim of this study was to evaluate the caprine preantral follicles enclosed on vitrified/warmed ovarian cortex grafted to nude BALB/mice during 1 month. The ovarian cortex from goats was fragmented (3 × 3 × 0.5 mm) and divided into four groups: fresh control, vitrified control, fresh transplant and vitrified transplant. Follicular morphology, development and density, fibrosis as well as apoptosis, and tissue revascularization were evaluated. It was also observed a significant decrease in morphologically normal preantral (primordial, transition, primary and secondary) follicles in both vitrified control and vitrified transplant treatments when compared with both fresh control and fresh transplant. However, fresh control and fresh transplant exhibited a similar percentage of developing follicles. Additionally, Vitrified control showed a significant increase in developing follicles in comparison with both fresh control and fresh transplant. Follicular density significantly decreased in all treatments in comparison with fresh control. We observed high fibrosis in both fresh transplant and vitrified transplant. The mRNA expression of caspase 3 was lower in both fresh transplant and vitrified transplant in comparison with vitrified control. In conclusion, xenotransplantation is an excellent strategy to maintain normal preantral follicle morphology after vitrification/warming of goat ovarian tissue. Yet, in order to ensure the survival and development of these follicles, it is essential to improve the revascularization of the graft.  相似文献   
995.
Semen banking is critical to preserving rare and autochthonous breeds. However, protocols can change with time, leaving heterogeneous semen batches. The objective of this study was to assess differences in sperm quality and field fertility. We report differences between batches frozen with the Biociphos and BIOXCell extenders in the Asturiana de la Montaña cryobank (autochthonous and endangered breed, Northern Spain). Doses from 48 bulls were analysed by CASA and flow cytometry. The 85‐days non‐return rates from AI records were used to assess the fertility of 23,853 AI. BIOXCell showed higher quality post‐thawing. Differences increased after a 5‐hr incubation at 37°C, and Biociphos yielded doses with lower resilience. Field fertility did not differ between extenders (Biociphos: 57.4% ± 1.2; BIOXCell: 56.6% ± 3.0), possibly because of AI protocols compensating for differences in quality. However, this needs to be confirmed by controlled intervention studies. In conclusion, batches frozen with Biociphos may require specific strategies for compensating for the lower sperm quality. Regular surveys and evaluation of cryobank procedures may be useful to characterizing stored batches and defining strategies to guaranteeing success in their future use.  相似文献   
996.
Over the last four decades, plastination has been one of the best processes of preservation for organic tissue. In this process, water and lipids in biological tissues are replaced by polymers (silicone, epoxy, polyester) which are hardened, resulting in dry, odourless and durable specimens. Nowadays, after more than 40 years of its development, plastination is applied in more than 400 departments of anatomy, pathology, forensic sciences and biology all over the world. The most known polymers used in plastination are silicone (S10), epoxy (E12) and polyester (P40). The key element in plastination is the impregnation stage, and therefore depending on the polymer that is used, the optical quality of specimens differs. The S10 silicone technique is the most common technique used in plastination. Specimens can be used, especially in teaching, as they are easy to handle and display a realistic topography. Plastinated silicone specimens are used for displaying whole bodies, or body parts for exhibition. Transparent tissue sections, with a thickness between 1 and 4 mm, are usually produced by using epoxy (E12) or polyester (P40) polymer. These sections can be used to study both macroscopic and microscopic structures. Compared with the usual methods of dissection or corrosion, plastinated slices have the advantage of not destroying or altering the spatial relationships of structures. Plastination can be used as a teaching and research tool. Besides the teaching and scientific sector, plastination becomes a common resource for exhibitions, as worldwide more and more exhibitions use plastinated specimens.  相似文献   
997.
The International Society for Plastination (ISP) was conceived as a means of defining plastination as an area of professional activity and serving as an agency for disseminating information relative to the art and science of plastination. In this paper, we present the purpose of ISP, the Journal of Plastination, the Plastination Index and the different international meetings organised by ISP.  相似文献   
998.
Body composition and energy requirements are different between males and females in several species, and both interfere with weight loss. The aim of this study was to compare the total and regional body composition and energy requirements in obese male (n = 8) and female (n = 8) cats, during weight loss and weight maintenance over 17 subsequent weeks after regimen. The total and regional (thoracic and pelvic limbs, and trunk) body composition was assessed by dual‐energy X‐ray absorptiometry (DXA). Females exhibited a higher fat mass (FM) than males (p < 0.05), and the trunk was the site with greater fat accumulation regardless of gender. A 23.0 ± 2.8% reduction in body weight was followed by a 50.3 ± 9.4% and a 37.0 ± 8.9% reduction in fat in the trunk region in males and females respectively. Lean mass (LM) mobilization was also increased in the trunk (p < 0.05), and the loss of LM was associated with a reduction in bone mass. The energy intake to achieve the same rate of weight loss was 12.9 ± 3.4% higher in males (p < 0.05). The cats exhibited a gradual increase in energy requirements to maintain their body weight after weight loss (p < 0.05). It was concluded that obese cats mainly accumulate fat in the trunk. The reduction in lean mass after the regimen also occurred in the trunk, with no modifications in the skeletal muscle mass of the limbs. Neutered male cats have higher energy requirements than neutered females, and gender should be considered during obesity management in cats.  相似文献   
999.

Context

Land-use change impacts biodiversity and ecosystem services, which are intrinsically related. There is a serious lack of knowledge concerning on how land-use change affects this relationship at landscape level, where the greatest impacts have been reported. A proper knowledge of that relationship would provide crucial information for planning conservation strategies. The forest landscape of southern Chile, which includes Valdivian Temperate Forest, has been designated as a hotspot for biodiversity conservation. However, this landscape has been transformed by land-use change.

Objective

We evaluated the impact of land-use change on the spatial patterns of the diversity of native forest habitat and the influence of these impacts on the provision of the ecosystem services water supply, erosion control, and organic matter accumulation from 1986 to 2011.

Methods

The evaluation, at the landscape level, was carried out using satellite images, landscape metrics, spatially explicit models and generalized linear models. Results: We found that the area loss of native forest habitat was 12%, the number patches of native forest habitat increased more than 150% and the Shannon diversity index decreased by 0.20. The largest decrease in the provision of services was recorded for erosion control (346%), and the smallest for water supply (11%).

Conclusions

The loss of provision of the ecosystem services can be explained by the interaction between the area loss, increase in the number patches and diversity loss. We recommend that the conservation planning strategies should consider the current landscape configuration, complemented with land-use planning.
  相似文献   
1000.
This work characterized the egg residual concentrations of albendazole (ABZ ) and its sulphoxide (ABZSO ) and sulphone (ABZSO 2) metabolites and evaluated their effect on egg fertility and hatchability after ABZ treatments to laying hens. Seventy hens were allocated in groups: Group‐1 was the control without treatment; Group‐2 received a single ABZ oral dose (10 mg/kg); Group‐3, ‐4 and ‐5 were treated with ABZ in medicated feed over 7 days at 10, 40, or 80 mg kg?1 day?1, respectively. Eggs were analyzed to determine the ABZ /metabolite level by HPLC or subjected to incubation to evaluate the fertility and hatchability. Only ABZSO and ABZSO 2 metabolites were quantified in egg after ABZ single oral administration with maximum concentrations of 0.47 ± 0.08 and 0.30 ± 0.07 μg/ml, respectively. ABZ and its metabolites were found in eggs after 7‐day ABZ treatments. The egg residue exposure estimated as AUC s (areas under the concentration vs . time curve) were 100.5 (ABZ ), 56.3 (ABZSO ) and 141.3 μg hr g?1 (ABZSO 2). ABZ administration did not affect the egg fertility at any dosages. Egg hatchability was not affected by ABZ treatment at 10 mg/kg in medicated feed, but it decreased when the dose was 4–8 times higher. These results should be considered when ABZ is used for deworming laying hens.  相似文献   
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