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1.
The aim was to verify the effect of follicle‐stimulating hormone (FSH) supplementation to α‐MEM+ or TCM199+ media on the in vitro development of ovarian preantral follicles (PFs) derived from collared peccaries. Ovaries (n = 5 pairs) were collected and divided into fragments destined to control group (non‐cultured) or treatments that were cultured for 7 days. The PFs morphology, growth and activation were evaluated by classical histology. The immunohistochemistry markers Ag‐NOR and PCNA were used for nuclear proliferation analysis, and the picrosirius red labelling was used for ovarian extracellular matrix (ECM) evaluation. After 7‐day culture, only the TCM199+ treatment maintained the proportion of intact PFs similar to day 1 (63.2%), but no differences were found among treatments (p > .05). In addition, a significant increase in the growing follicles proportion was verified for all the treatments, indicating follicular activation (p > .05). By the Ag‐NOR analysis, only the TCM199+/FSH maintained the nuclear proliferation similar to the first day (p > .05). The picrosirius red staining revealed that the ECM remained intact in all the treatments (p > .05). We suggest the use of TCM199+ medium supplemented of FSH for the in vitro development of peccaries PFs under 7‐day culturing conditions.  相似文献   
2.

Background  

The establishment of mutant populations together with the strategies for targeted mutation detection has been applied successfully to a large number of organisms including many species in the plant kingdom. Considerable efforts have been invested into research on tomato as a model for berry-fruit plants. With the progress of the tomato sequencing project, reverse genetics becomes an obvious and achievable goal.  相似文献   
3.
Current distribution of sarcoptic mange in wombats   总被引:2,自引:0,他引:2  
Objective To determine the distribution and prevalence of sarcoptic mange in wombats, particularly the common wombat ( Vombatus ursinus ).
Design Questionnaire survey in two parts.
Procedure Questionnaires were distributed to biologists, rangers, animal carers and naturalists. Part 1 of the questionnaire aimed to determine the present distribution of sarcoptic mange in wombats (103 responses). Part 2 invited respondents to assess the prevalence of sarcoptic mange in wombats over a 3 month period (four responses). Information on wombats from 66 localities was received. Each locality represented an area of about 2500 km2.
Results Mange was observed at 93% of localities surveyed and Sarcoptes scabiei was present in common wombats at 52% of localities. Sarcoptic mange was highly prevalent (22%) in two common wombat populations in Victoria. Anecdotal evidence suggested that mange epizootics are sporadic, cause significant morbidity and mortality and have a substantial effect on local abundance. The respondents did not report sarcoptic mange in either northern hairy-nosed wombats ( Lasiorhinus krefftii ) or southern hairy-nosed wombats ( Lasiorhinus latifrons ).
Conclusions Sarcoptic mange occurs in common wombat populations throughout the range of the common wombat including Tasmania and Flinders Island. While mange epizootics are sporadic, they have the potential to threaten the long-term survival of small, remnant populations.  相似文献   
4.
An adult female bearded dragon (Pogona vitticeps) presented to the University of Georgia Veterinary Teaching Hospital for an area of swelling affecting the left eye of approximately 3 years’ duration. Upon examination, the left eye could not be evaluated due to an extensive periorbital mass effect. Hematologic and advanced diagnostic testing were recommended, but due to financial concerns the owner declined. Ultimately, the patient was humanely euthanized and was submitted for necropsy. The mass was diagnosed via histopathology as a cystadenoma of the eyelid. Phthisis bulbi of the left eye with granulomatous inflammation was also observed.  相似文献   
5.
Inhibitors of cyclin‐dependent kinases, as roscovitine, have been used to prevent the spontaneous resumption of meiosis in vitro and to improve the oocyte developmental competence. In this study, the interference of oil overlay on the reversible arrest capacity of roscovitine in sheep oocytes as well as its effects on cumulus expansion was evaluated. For this, cumulus‐oocyte complexes (COCs) were cultured for 20 h in TCM 199 with 10% foetal bovine serum (Control) containing 75 μm roscovitine (Rosco). Subsequently, they were in vitro matured (IVM) for further 18 h in inhibitor‐free medium with LH and FSH. The culture was performed in Petri dishes under mineral oil (+) or in 96 well plates without oil overlay (?) at 38.5°C and 5% CO2. At 20 and 38 h, the cumulus expansion and nuclear maturation were evaluated under stereomicroscope and by Hoechst 33342 staining, respectively. No group presented cumulus expansion at 20 h. After additional culture with gonadotrophins, a significant rate of COCs from both Control groups (+/?) exhibited total expansion while in both Rosco groups (+/?) the partial expansion prevailed. Among the oocytes treated with roscovitine, 65.2% were kept at GV in the absence of oil overlay while 40.6% of them reached MII under oil cover (p < 0.05). This meiotic arrest was reversible, and proper meiosis progression also occurred in the Control groups (+/?). So, the culture system without oil overlay improved the meiotic inhibition promoted by roscovitine without affecting the cumulus expansion rate or the subsequent meiosis progression.  相似文献   
6.
7.
Summary Improved crop varieties developed at experimental stations are intended for release for production in farmers' fields which are not necessarily the test sites. Therefore, it is important to measure the inter-site transferability of the crop variety. This study was undertaken to establish a statistical measure of inter-site transferability of a variety. Data on grain yield from two sets of multi-locational trials on barley and four sets of the wheat trials conducted by the Cereal Program, International Center for Agricultural Research in the Dry Areas, Syria, were analyzed to evaluate the inter-site transferability of the varieties. Genotype × environment interaction was significant and experimental errors were heterogeneous in each set of trials. Correlations between the slope (of linear regression of variety mean on location mean) and variety mean were significant (P < 0.01) in all trials. Correlations between the developed inter-site transferability statistic and the variety mean were significant (P < 0.05) in only two trials. Correlations between mean yield and probability of the inter-site transferability statistic were insignificant in all trials. The inter-site transferability statistic and the associated probability of the transferability may be used to select varieties which are high yielding as well as transferable to a new environment. The strong association of slope with mean yield restricted the scope of varietal selection but the introduced statistic did not suffer from this drawback.  相似文献   
8.
A total of 35 ejaculates were studied in order to assess the suitability of porcine semen for freezing according to the ejaculate characteristics. The effects of the freezing procedure were identified; a decrease in motility and acrosome quality was found after thawing. The best results on motility were linked to the ejaculates with a volume of less than 100 ml of the sperm‐rich fraction, a concentration lower than 450 × 106 spermatozoa/ml and an agglutination score below 2. However, the best normal apical ridge (NAR) was found when the volume of the sperm‐rich fraction was greater than 150 ml. For this reason, an intermediate volume of the sperm‐rich fraction of the ejaculate for the best motility and the best NAR, a concentration lower than 450 × 106 spermatozoa/ml and a rate of agglutination below 2 should provide the best quality after freezing. This study also attempted to determine whether a positive effect of ejaculate selection on the overall freezing performance might be expected.  相似文献   
9.
Sui-Kwong Yau 《Euphytica》2002,123(3):307-314
Three plastic-house experiments were conducted to compare the tolerance of European with West Asian and North African (WANA) winter barleys to boron (B) toxicity. Experiment I screened 24 winter barley entries with diverse origins. Experiment III tested 420 random accessions from seven European and seven WANA countries. Plants were screened in a soil mixed with boric acid (50 mg B/kg) and foliar B-toxicity symptom scores were recorded. Lower scores indicated higher B-toxicity tolerance. In Experiment II, five lines/varieties from each of the European and WANA groups were grown in pots with two soil B levels (0 and 25 mg B/kg). The West Asian landrace barleys had a lower mean B-toxicity symptom score than the European ones. The Syrian landrace variety normally grown in drier areas had a lower score than the Syrian landrace variety grown in wetter areas. Dry weights of the European and WANA groups were not different without adding B, but dry weight under 25 mg B/kg was lower for the European group than the WANA group. European accessions had a higher mean B-toxicity symptom score than the WANA accessions. Iranian and Afghan accessions had the lowest mean scores among countries. These results support the hypothesis that European winter barley varieties and accessions are less tolerant to B toxicity than those WANA accessions and varieties developed from local landraces. The lower B-toxicity tolerance could be a factor adversely affecting the performance of European winter barley varieties in the highlands of WANA. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
10.
Light adaptation in cat retinal rods   总被引:8,自引:0,他引:8  
It has long been an open question whether individual rod receptors in the mammalian retina show any light adaptation. The prevailing evidence so far has suggested that these cells, unlike those in lower vertebrates, adapt little if at all. The experiments on cat rods reported here, however, indicate that this is not really true. Since the cone system in the cat retina has a fairly high light threshold, the rods also need to adapt so that they do not saturate with light before the cones fully take over vision at higher light intensities. In similar experiments, adaptation was found in rods of other mammalian species, including primates.  相似文献   
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