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31.
The aim of this study was to test and compare two new components in extenders for freezing donkey semen: mare colostrum and jenny colostrum. Colostrum was obtained from four mares and four jennies right after the foal's birth. Ejaculates were collected from five fertile donkeys. Sperm samples were pooled, diluted and cryopreserved in three different experimental extender groups: lactose supplemented with egg yolk extender (20%) as the control group, lactose supplemented with jenny colostrum extender (20%), and lactose supplemented with mare colostrum extender (20%). After thawing, we evaluated the sperm motility by means of computer‐assisted analysis, viability by SYBR‐14 and propidium iodide (PI), membrane functional by HOS test and acrosome integrity by isothiocyanate conjugated with peanut agglutinin (FITC‐PNA) and PI. The results demonstrated that lactose–jenny colostrum extender displayed significantly higher values (p < .05) in nearly all parameters evaluated – Total Motility, Viability, HOS test, VCL, VSL, VAP, LIN, STR and WOB –, compared with mare colostrum and egg yolk extenders after thawing. In conclusion, the extender containing jenny colostrum used for donkey semen cryopreservation improved the donkey sperm quality after the freezing–thawing process.  相似文献   
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A die-off occurred in a captive colony of blue-winged grasshoppers (Tropidacris collaris) at the Toronto Zoo. One fourth of the colony died within a year due to infection with worms initially mistaken for nematomorphs but later identified as nematodes belonging to the Mermithidae, genus Mermis. Mortality persisted and the grasshopper population dwindled over the following years. Mermithid larvae developed in the hemocoel of the insects until they eventually emerged from a hollowed-out exoskeleton. Circumstantial evidence suggests that the parasites were introduced with raspberry browse that was grown on site and contaminated with mermithid eggs.  相似文献   
33.
Iridophores are iridescent cutaneous pigment cells found in reptiles, fish, and amphibians. Neoplasms of iridophores are rarely reported, and little is known about their behaviour, metastatic potential, and prognostic indicators. This paper reports details of the clinical course and pathological findings of metastatic iridophoroma in a veiled chameleon (Chamaeleo calyptratus) and red-barred dragon (Ctenophorus vadnappa). The veiled chameleon presented with a subcutaneous mass on the right lateral elbow and was diagnosed as an iridophoroma on fine needle aspiration. It was otherwise clinically normal. Within 35 days of excision, multiple secondary skin masses developed which were often non-pigmented and required microscopic examination to identify them as iridophoroma metastases. There were in total 54 days between the first detection of the primary mass and end stage, extensive cutaneous and visceral metastatic disease, and there had been no detectable primary mass during routine clinical examination 128 days prior to death. The red-barred dragon presented with a white sub-mandibular mass. While undergoing an excisional biopsy the animal expired, post-mortem examination revealed a cutaneous malignant iridophoroma with tumour cell clusters seen in pulmonary arterial vessels, suggesting that surgical handling of iridophoroma could precipitate the release of circulating tumour cell clusters. This is the first iridophoroma described in a red-barred dragon and the second report of a malignant iridophoroma in a veiled chameleon. Timely detection and careful excision of lizard iridophoroma may be an important factor in clinical outcome.  相似文献   
34.
Changing immune parameters during pregnancy have previously been reported in humans and cattle, and have been suggested to contribute to increased susceptibility to infections. However, data regarding immune parameters during pregnancy in sows are rare. In this study, we investigated the peripartal immune status of sows using phenotypical (FACS analysis) as well as functional (proliferation assays, cytokine analysis) parameters of peripheral blood mononuclear cells (PBMCs) in pregnant sows. In previous studies, we reported a modulation of the immune system after feed supplementation of the probiotic Bacillus cereus var. toyoi in piglets [Schierack, P., Wieler, L.H., Taras, D., Herwig, V., Tachu, B., Hlinak, A., Schmidt, M.F., Scharek, L., 2007. Bacillus cereus var. toyoi enhanced systemic immune response in piglets. Vet. Immunol. Immunopathol. 118, 1–11]. Here, we extended these previous studies to include investigations of possible probiotic effects on the peripartal immune status of sows and their reproductivity. We show that immune parameters of sows change during pregnancy, the proliferative response of PBMCs to several bacterial antigens in control animals decreased from days 90 to 30 ante partum. Relative numbers (%) of CD3+CD8+, CD4+, cytotoxic T, CD14+ and CD21+ cells were reduced compared to non-pregnant sows. In contrast, the proliferative response of PBMCs of probiotic-treated sows increased during pregnancy. Bacterial antigens primarily stimulated the proliferation of naïve CD21+ cells and the relative CD21+ cell numbers were elevated in the probiotic group in the absence of effects on other immune cell populations. The clinical and microbial status of both control and probiotic sows was similar, excluding pre-existing health problems or infections as responsible for the immunological changes, and feed supplementation also had no significant effects on reproductivity. The results suggest that the probiotic B. cereus var. toyoi can alter the proliferative response of lymphocytes and affects the immune cell population ratios of pregnant sows. How and to what extent this may affect health and reproductivity should be the focus of further studies.  相似文献   
35.
In this work the antiviral activity of 20 dehydroepiandrosterone (DHEA) analogs with different substituents at positions C-3, C-15, C-16 and C-17 were evaluated against vesicular stomatitis virus (VSV) in Vero cell cultures. The selectivity indexes (SI) obtained with DHEA and epiandrosterone (EA) were 50 and 72.6, respectively. The work showed that the compounds 21-norpregna-5,17(20)-dien-3β,16α-diyl-diacetate, 17,17-ethylendioxyandrostan-5,15-dien-3β-ol and 3β-hydroxypregn-17(20)-en-16-one had higher SI values than ribavirin, which was used as a reference drug. The antiviral mode of action of DHEA was also investigated against VSV replication in Vero cells, and time of addition experiments showed that DHEA mainly affected a late event in the virus growth cycle. Analysis of RNA and protein synthesis indicated that DHEA adversely affected positive strand RNA synthesis and viral mature particle formation.  相似文献   
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This study compared 38 sainfoin and 2 Lotus accessions to their respective tannin contents, N buffer solubility, and in vitro protein degradation. Tannin contents were measured by a protein precipitation method using either bovine serum albumin or Rubisco and by the colorimetric HCl/butanol method. Precipitation of bovine serum albumin and Rubisco was highly correlated (R(2) = 0.939). Correlations between the protein precipitation variants and the HCl/butanol method were relatively low (R(2) < 0.6). Protein degradation was measured at 4 h of incubation in an inhibited in vitro system and could not be explained by any of the tannin assays (R(2) < 0.03) and only partially by N buffer solubility (R(2) ≤ 0.433). Decisive factors other than the quantity of tannins or their ability to precipitate proteins must be considered. Resistance of soluble protein toward degradation can possibly be caused by tannin protein binding.  相似文献   
40.
Sainfoin (Onobrychis viciifolia Scop.) is a perennial forage legume that possesses beneficial properties in the context of sustainable agriculture. In order to initiate a pre-breeding programme, we have assembled a germplasm collection of O. viciifolia from many geographic regions, as well as a collection of Onobrychis species that might be crossed with O. viciifolia to improve its biological and agronomic properties. The objective of this study was to obtain DNA sequences from a representative sample of these accessions in order to characterise their genetic diversity and to assess the robustness of the Onobrychis taxonomy. Because of potential problems with copurification of tannins and polyphenols from Onobrychis leaf tissue, three methods for DNA extraction were assessed and the most appropriate one identified. DNA sequences were obtained for the nuclear internal transcribed spacer region and the trnH-psbA and trnT-trnL intergenic spacers of the chloroplast genome. Neighbour joining trees were constructed and accessions were assigned to operational taxonomic units. The results indicated that there is substantial genetic diversity among Onobrychis species. Redundancies in species nomenclature were identified, as well as possible overlap between some of the sections into which the Onobrychis genus has been divided. A genetic distinction was apparent between O. viciifolia accessions from western Europe and those from eastern Europe and Asia, reflecting a similar division based on agronomic properties. Recognition of these different though related germplasms will be valuable in the design of breeding programmes for the rational improvement of sainfoin as a forage crop for sustainable agriculture.  相似文献   
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