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481.
482.

Ethiopia is home to a diverse gene pool of indigenous sheep populations. Therefore, a better understanding of genetic variation holds the key to future utilization through conservation. Three of these breeds, Afar, Blackhead Somali, and Hararghe Highland, are found in eastern Ethiopia where they contribute significantly to the livelihood of most pastoralist, agro-pastoralist, and smallholder farmers. These indigenous sheep are recognized on the basis of morphotype and their genetic distinction remains unknown. Here, to assess genetic variation, and matrilineal genetic origin and relationship of fat-rumed sheep found in eastern Ethiopia, 300 individuals from the three breeds were genotyped for 22 microsatellite markers and sequenced for the mitochondrial DNA displacement loop (mtDNA d-loop) region. The overall HO and HE were 0.57 and 0.75, respectively. Differentiation statistics revealed that a high proportion (97%) of the total genetic variation was explained by differences between individuals within populations. Genotype assignment independent of the population of origin showed K?=?2 to be the optimum number of genetic backgrounds present in the dataset. This result was further confirmed by mtDNA D-loop sequences comparison in which the matrilineal genetic origin of eastern Ethiopia sheep is from two haplotype groups (types A and B) among the five haplotypes globally observed. Taken together, our findings suggest that the sheep populations from three breeds originated from two ancestral genetic backgrounds that may have diverged prior to their introduction to Ethiopia. However, to obtain a complete picture of the evolutionary dynamics of Ethiopian indigenous sheep, more samples and populations from within and outside of the country will need to be analyzed.

  相似文献   
483.
Tropical Animal Health and Production - The aim of the study was to determine some ergonomic parameters of donkeys administered with Pycnogenol® (PYC) and subjected to packing during the...  相似文献   
484.
Novel 5-amino-1-phenylpyrazol-4-yl alkyl ketones were synthesised and their herbicidal properties evaluated. Active compounds in the series induced accumulation of protoporphyrin IX in etiolated cucumber cotyledons and caused light-dependent herbicidal effects in 21-day-old cucumber plants. Structural features of the pyrazoles that contributed to herbicidal potency were found to be a high degree of halogen substitution in the 1-phenyl ring, no substitution in the pyrazole 3-position, and an ethyl group as the alkyl component of the ketone. The structure of 1-[5-amino-1-(2,4,6-trichlorophenyl)pyrazol-4-yl]-2-methylpropan-1-one was determined by X-ray crystallography.  相似文献   
485.
486.
Striped skunks (skunks) are susceptible to respiratory infection by influenza A viruses (IAV). As they are common synanthropes, maintenance of IAV in skunks could provide a source of infection for humans. We previously studied the nasal turbinates, lungs and faeces of 50 free‐ranging skunks for the presence of IAV and identified two individuals with influenza A(H1N1)pdm09 infection during the 2009/2010 and 2013/2014 flu seasons. Subsequent to publication of that study, ferrets were shown to preferentially replicate and harbour A(H1N1)pdm09 in the soft palate, a site which had not been investigated in the skunks. From March 2015 to May 2016, we surveyed a convenience sample of 80 free‐ranging urban skunks for IAV in soft palate, nasal turbinates and lungs. The newly emergent influenza A(H1N1)pdm09 clade 6B.1 was detected at all three sites in one skunk with acute rhinitis in February 2016. Clade 6B.1 was the dominant clade in circulation during the 2015/2016 flu season. As the skunk was detected at the height of flu season, reverse zoonosis was considered the most probable source of infection.  相似文献   
487.
The introduction of a new group of dendrobatid frogs to an established captive amphibian collection was followed by several acute mortalities in both resident and introduced frog populations. Chytridiomycosis, caused by Batrachochytrium dendrobatidis, was diagnosed by histology in two of the dead frogs. Following the diagnosis, all amphibians were moved to a specially made quarantine room with strict handling protocols and treated with itraconazole. Frogs, being terrestrial amphibians, were treated with itraconazole (Sporanox, 10 mg/ml) at 0.01% in 0.6% saline in a 5-min bath for 11 consecutive days. Axolotls (Ambystoma mexicanum) and Kaup's caecilians (Potymotyphlus kaupii), being aquatic amphibians, were treated with itraconazole administered directly in their primary tank water to achieve a concentration of 0.01% for 30 min every 5 days for four treatments. Itraconazole was removed from the tank water after 30 min by high-rate-of-flow activated charcoal filters. The treatment and quarantine procedures were successful in eradicating the disease. The few amphibian mortalities that occurred in the 18 mo after the start of the treatment have been histologically negative for the presence of chytrid fungi. The collection is now considered free of chytridiomycosis.  相似文献   
488.
Mineralization of paraprostatic cysts is reported to be uncommon. This retrospective study was performed to review the imaging findings of eight histologically confirmed canine paraprostatic cysts. Radiographic patterns of mineralization seen are described. Four of the eight dogs had mineralized cysts. Mineralization seen on radiography was not consistently seen on ultrasonography, probably due to the lack of acoustic shadowing artefact from the small depth of mineralized tissue. It is thus concluded that mineralization of paraprostatic cysts is more common than implied in the literature, and that radiography is superior to ultrasonography in identifying its presence.  相似文献   
489.
ABSTRACT

Gold kiwifruit (Actinidia chinensis Planch. var. chinensis ‘HORT16A’, marketed as ZESPRI?' ‘HORT16A’) is an important export crop for New Zealand. Nutrient management, including the application of nitrogen (N), for ‘HORT16A’ kiwifruit has mimicked strategies for the green (A. deliciosa ‘Hayward’) cultivar, however, physiological differences between Actinidia species necessitate the development of specific nutrient regimes for ‘HORT16A’ vines. In this trial, all nutrients, except N, were applied at levels comparable to commercial practice. The Control treatment received approximately 145 kg N ha/y, and was based on estimates of total N removed each year in the harvested fruit. The Zero-N treatment vines received all nutrients except N, and the High-N treatment received double the Control, approximately 295 kg N ha/y, for two consecutive seasons. The High-N treatment represents the upper limit of N application practices in commercial ‘HORT16A’ kiwifruit production. Zero-N fruit had higher calcium (Ca) and lower N concentration than High-N fruit in both seasons. Fruit potassium (K) and magnesium (Mg) concentrations were equivalent between these treatments in both seasons. Fruit phosphorus (P) concentration throughout the season was increased in the High-N treatment in both years. Fruit sizes were not different between treatments at final harvest in Year 1, being 130.5 ± 4.13 g, 125 ± 1.49 g, and 125 ± 3.29 g for the High, Control, and Zero-N vines, respectively. Larger fruit were harvested from the High-N vines (125 ± 4.69 g) in Year 2, than from either Control (113 ± 2.03 g) or Zero-N (118 ± 1.03 g) vines. Percent fruit dry matter (DM) content was higher in the Zero-N fruit (17.2 ± 0.06, 17.2 ± 0.06, and 16.8 ± 0.14 for Zero, Control, and High-N vines) at final harvest in Year 1. But values of fruit DM for all treatments were similar in Year 2 in spite of fruit size differences between treatments. Fruit DM for all treatments was slightly higher in Year 2 than in Year 1. Differences in fruit mineral concentration and fruit maturity at harvest may have contributed to increased incidence of low temperature breakdown (LTB) in the High-N fruit in Year 1. In Year 2, when fruit DM was higher in all treatments, yellow coloration was more developed. Total fruit N concentration was lower in Year 2 for all treatments than in Year 1, and LTB was minimal and not different between treatments.

Leaves from Zero-N vines had reduced N in both years compared with Control and High-N vines. In contrast, leaf Ca and Mg concentrations were reduced in High N-vines, compared with values recorded in Zero-N vines in both seasons. Leaf K concentrations were comparable between treatments in both seasons. Leaf sulfur (S) concentration was reduced under the High-N treatment, and leaf P levels were increased under the High-N treatment in both years.

These data demonstrate that N application influences the uptake and accumulation of other mineral elements in ‘HORT16A’ kiwifruit. In order to encourage desirable nutrient concentrations in both the fruit and leaves of ‘HORT16A’ kiwifruit, a reduction in N applied is suggested, and this would have little or no detrimental effect on vine performance over two seasons. Reduced N application will also reduce nitrate leaching which is estimated at 39 kg N ha/y under the Control treatment.  相似文献   
490.
Equine recurrent airway obstruction (RAO) is an inflammatory, obstructive airway disease induced by exposure of susceptible horses to inhaled organic dust particles. The immunological process underlying RAO is still unclear. Previous studies have shown that RAO is linked to the Interleukin-4 receptor (IL-4R) gene in one Warmblood family (F1), but not in another (F2). It has also been shown that in F1, but not in F2, RAO is associated with resistance against parasites, suggesting that this association may have an immuno-genetic basis. Therefore, we hypothesized that the T helper (h)1/Th2/regulatory (Treg) cytokine profiles of RAO-associated antigen- and parasite-antigen-stimulated peripheral blood mononuclear cells (PBMC) differ between RAO-affected and healthy horses depending on their genetic background. In our study, PBMC from 17 RAO-affected and 14 healthy control horses of F1 and F2 were stimulated for 24 h with antigens relevant to RAO [hay dust extract (HDE), Aspergillus fumigatus extract (AFE) and lipopolysaccharids (LPS)]; cyathostomin extract (CE) and recombinant cyathostomin antigen (RCA) or with concanavalin A (ConA). Total mRNA levels of IL-4, IL-4R, IL-13, interferon (INF)-γ and IL-10 were examined by qRT-PCR. Stimulation with either HDE or RCA resulted in significant differences in IL-4R mRNA levels between RAO-affected and control horses in F1, but not in F2. For IL-10 mRNA expression, a significant difference between RAO-affected and control horses in F1 but not in F2 was observed only following stimulation with HDE. In contrast to HDE, stimulation with CE resulted in a significant difference of IL-10 mRNA expression level between RAO-affected horses of F2 and healthy horses of F1. No significant differences were detected upon stimulation with any of the other challenge agents. These findings indicate that the immunological response, specifically IL-4R expression, in response to hay dust and cyathostomin antigens, differs between RAO-affected and healthy horses depending on their genetic background. This study shows that analysis of PBMC reveals systemic changes associated with RAO and helps to elucidate immunological pathways involved in this disease.  相似文献   
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