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1.
Semen and blood samples from 154 rams from two Montana range flocks (Flock A, vaccinated for Brucella ovis ; Flock B, nonvaccinated) were evaluated to determine the relationship between Brucella ovis (B. ovis ) semen culture results and various semen and blood parameters. All rams utilized in this study exhibited no palpable ram epididymitis lesions. Thirteen and 25.6% of the rams tested in Flocks A and B, respectively, had positive B. ovis semen cultures. Only age of ram and ram condition scores differed (P<0.05) between flocks. No flock by semen culture interactions were detected (P>0.05) for any of the parameters evaluated. Age of ram, ram condition score, and spermatozoa rate from forward movement were unrelated (P>0.05) to B. ovis culture results. Rams with positive B. ovis semen cultures had lower sperm motility (P<0.05), higher percentage of abnormal spermatozoa cells (P<0.05), higher percentage of spermatozoa head abnormalities (P<0.01), lower percentage of live-normal cells (P<0.05), higher incidence of white blood cells in semen (P<0.01) and higher complement fixation (CF) titers (P<0.01).  相似文献   

2.
A breeding soundness examination (BSE) involving animal physical examination, scrotal circumference (SC) and semen evaluation was undertaken on 80 Ile-de-France rams at a government breeding farm, 32 km south-west of Casablanca (Morocco) from March to May 1988. A large percentage of rams (21.4%) was found to be unfit for breeding due to physical and genital abnormalities; 11 and 5% had disorders of the feet and respiratory system; upon genital palpation, 17.5, 13.8 and 7.5% of animals had orchitis, epididymitis and posthitis, respectively. The SC increased with age from 28.8+/-3.2 cm at 相似文献   

3.
Ray flower and leaf flavonoids were investigated for the three species of Helianthus series Microcephali. Ray flowers of all species contain coreopsin, sulphurein, and quercetin 7-O-glucoside; those of H. microcephalus also contain quercetin 3-O-glucoside. A mixture of flavonoid aglycones, mostly methoxylated flavones, occurs in leaves of H. microcephalus, but not in H. glaucophyllus or H. laevigatus which also lack the glandular trichomes that in Helianthus are typically associated with flavonoid aglycones. The presence of compounds with the 6,8,4′ pattern of methoxylation in H. microcephalus suggests that the series is more similar in flavonoids to series Angustifolii than to series Corona-solis.  相似文献   

4.
Leaf and ray flower flavonoids were investigated for the seven species of Helianthus series Angustifolii. Flavone aglycones occur in small glandular trichomes located on leaf undersurfaces of H. angustifolius, H. floridanus and H. simulans. Other species lacked both glandular trichomes and flavone aglycones. Flavonol glycosides occur in low concentrations in leaves of all species but were not characterized. Anthochlors (chalkones) occur in leaves of H. heterophyllus and H. longifolius. Ray flower flavonoids include anthochlor and flavonol glycosides and occur in the basal region of the ligule producing a band of UV A around the head. Anthochlors are the predominant ray flower flavonoids in H. angustifolius, H. heterophyllus and H. longifolius, whereas they are absent and quercetin 7-glucoside is present in H. carnosus and H. floridanus. Cladistic analysis of flavonoid and morphological characters indicates that evolution in the series has been a radiation from ancestral types rather than a linear sequence of progressively more derived species.  相似文献   

5.
Ram lambs (7–8 months old) and mature rams (19–20 months old) were used to evaluate the effect of classification levels of male sexual performance on reproductive performance of ewes during spring breeding. In Exp. 1, sexually active ram lambs with high (1.8±0.3; n=5) and low (0.9±0.2; n=5) sexual performance scores (HP and LP; mean±S.E.M.) were used in single sire breeding pens. Ewes (n=305) were stratified by age and assigned to 10 pens for 34 days starting in late March. For Exps. 2 and 3, two replicates were conducted for 2 years with sexually active mature rams in a single sire mating scheme. For Exp. 2, HP rams (n=5) averaged 3.6±0.2 ejaculations and LP rams (n=7) 1.8±0.2 ejaculations for sexual performance scores based on nine, 30 min serving capacity tests (SCT). Polypay ewes (n=152 to 153 per year) were stratified by age and assigned to pens each year for 34–38 days starting in late March for years 1 and 2. For Exp. 3, HP rams (n=6) averaged 3.7±0.1 ejaculations and LP rams (n=10) 2.3±0.1 ejaculations for sexual performance scores based on 18, 30 min SCT. Polypay ewes (n=229 in year 3 and n=244 in year 4) were stratified by age and assigned to pens each year for 34 days starting in late March. In Exp. 1, lambing rates for ewes bred to HP versus LP ram lambs did not differ (65.8 versus 53.0; P=0.20). Prolificacy tended (P=0.06) to be increased by 0.1 lambs in ewes bred by LP ram lambs. Total number of lambs born per ewe present at lambing, and lambing distribution were not altered by HP and LP ram lambs. In Exp. 2, lambing rates for fall-lambing ewes bred to mature HP or LP rams did not differ (58.1 versus 60.1; P=0.78). In Exp. 3, lambing rates for fall-lambing ewes bred to mature HP or LP rams did not differ (74.3 versus 69.0; P=0.35). There was no difference (P>0.10) between years for Exp. 2 or Exp. 3, and mature HP and LP rams did not affect the other reproductive variables monitored. Analyses of the combined data for Exps. 2 and 3 indicated only a year difference (P<0.001) in lambing rates and total lambs born. Present studies indicate that different sexual performance classifications for ram lambs and mature rams did not alter lambing rates or distribution of lambing of Polypays bred in late March to April. These results indicate that HP and LP, sexually active, Polypay rams and ram lambs with average to high quality semen can provide a source of rams for spring breeding Polypays in ambient conditions and that there was no advantage to using HP over sexually active LP ram lambs or rams.  相似文献   

6.
Primary amoebic meningo-encephalitis (PAME) in mouse can be easily produced by intranasal inoculation of Naegleria aerobia Singh & Das, 1970 and Hartmannella culbertsoni Singh & Das, 1970. The ultrastructural characteristics of N. aerobia and H. culbertsoni from infected mouse brain tissues showed many similar characteristics. The distinctive features between the two were the retention of phagocytic activity by N. aerobia as well as pinocytic activity in the ingestion of food as compared to H. culbertsoni where only pinocytic activity was observed. Staining characteristics of mitochondria suggested that N. aerobia was more active in the brain tissues than H. culbertsoni. Membrane-bound darkly stained bodies of unknown function were found in the brains infected with both N. aerobia and H. culbertsoni. They may have some bearing on the pathogenicity of these amoebae. Human cases of PAME so far reported are mostly due to N. aerobia and rarely with H. culbertsoni. This may be due to certain inherent characteristics present in N. aerobia which help them to survive on human brain tissue. On the other hand, the same may be lacking in H. culbertsoni. These ultrastructural differences in both N. aerobia and H. culbertsoni, as revealed by electron microscope studies of the infected brain tissues of mice, are presented in this paper.  相似文献   

7.
The presence of alkaloids in six species of Brongniartia and three species of Harpalyce is reported. This survey revealed remarkable qualitative differences in the alkaloid profiles of these two genera. B. discolor, B. lupinoides, B. sousae and B. intermedia showed a typical -pyridone pattern, with cytisine, anagyrine and baptifoline as major alkaloids. In leaves of the first three species ormosanine-type alkaloids occurred additionally. B. flava and B. vazquezii are devoid of -pyridones, but accumulate lupanine, hydroxylated lupanines and ester alkaloids. All three species of Harpalyce were similar in accumulating -pyridones, but H. formosa differed from H. brasiliana and H. pringlei in the presence of epilupinine. In general the alkaloid profiles of Brongniartia and Harpalyce show similarities to those of the Australian genera Hovea, Lamprolobium, Plagiocarpus and Templetonia and support therefore the actual concept of the enlarged tribe Brongniartieae.  相似文献   

8.
The mitochondrial cytochrome b gene of seven species of sea eagles H. albicilla, H. leucocephalus, H. leucoryphus, H. leucogaster, H. sanfordi, H. pelagicus and H. vocifer was amplified by PCR and sequenced (1026 bp). Phylogeny reconstructions by the Maximum Parsimony and Neighbour-Joining methods produced similar trees in which sea eagles represent a monophyletic group. In addition, the clade H. albicilla/H. leucocephalus groups with the clade H. pelagicus/H. leucoryphus in a monophyletic boreal group while H. vocifer clusters with the H. leucogaster/H. sanfordi clade in a monophyletic tropical clade. The nearest relatives of sea eagles are the kites (genus Milvus) and buzzards (genus Buteo), whereas ‘booted’ eagles (genus Aquila) and vultures (genera Gyps and Aegypius) have diverged earlier from the accipitrid branch. Honey bussards (genus Pernis) and vultures of the genera Gypaetus and Neophron represent basal taxa of the accipitrid lineage. Falcons, New World vultures and the secretary bird (Sagittarius) appear in separate clades outside the Accipitridae.  相似文献   

9.
Five Hieracium species were examined for flavonoid constituents: H. albertinum, H. albiflorum, H. cynoglossoides, H. gracile and H. umbellatum. The major compounds present in all species were mono- and diglycosides, of apigenin and luteolin. Chrysoeriol occurred per se in several species. Quercetin-3-O-glucoside was seen only in H. umbellatum. Species specific patterns of flavonoid glycosides were evident in all five taxa; H. albertinum and H. cynoglossoides showed the greatest similarity which reflects their morphological similarity. Limited examination of artificial hybrids showed additivity of flavonoid glycoside patterns.  相似文献   

10.
The thermodynamic and spectral properties of the photochemical reaction center components of Heliobacterium chlorum have been examined. The primary electron donor bacteriochlorophyll has Em,7 = +225 mV, and the ‘primary acceptor’ Em,10 = −510 mV. The former has an EPR signal in its oxidised form near G = 2.0025, ΔH = 0.95 mT, reminiscent of the properties of the primary donor in bacteria containing bacteriochlorophyll a. The ‘primary acceptor’ has properties similar to those of the iron-sulfur cluster acceptors of green sulfur bacteria. H. chlorum contains a c-type cytochrome (Em,7 = +170 mV) that donates electrons to the photooxidised primary donor with . The reaction center of H. chlorum is thus very similar to that found in representative green sulfur bacteria, but the cellular architecture and photopigments of this group are quite distinct from those of H. chlorum.  相似文献   

11.
During 1983, 887 fine wool rams were subjected to breeding soundness evaluation to determine effects of age and scrotal circumference on semen characteristics. Of rams evaluated, 94.4, 84.8, and 81.9% of young (6 yr), respectively, were rated as satis-factory. Old rams had fewer (P < 0.05) motile cells and more (P < 0.05) abnormal cells than young rams. Among older rams there was a higher percentage (P < 0.05) with testicular lesions than among young or mature rams. Scrotal circumference was positively correlated (P < 0.01) with semen volume and percentage of motile normal cells. Motility was negatively correlated (P < 0.01) with percentage of abnormal cells. Mature and old rams with large (>/=36.7 cm) testis had more (P < 0.10) abnormal cells than those in the same age groups with smaller testis. Scrotal circumference was positively correlated (P < 0.10) to volume and motility in mature and old rams, while motility was negatively correlated (P < 0.01) to percentage of abnormal cells in all age groups. Previous semen testing reduced (P < 0.05) the percentage of mature rams with leucocytes. Vaccination against epididymitis reduced (P < 0.05) the incidence of mature rams with leucocytes and testicular lesions. Brucella ovis was recovered from 54 (67.5%) of 80 ejaculates cultured. Among rams infected with B . ovis , only three (5.6%) were vaccinated against B . ovis and had their semen tested previously.  相似文献   

12.
蓝昭军  林龙峰  赵俊 《生态学杂志》2017,28(4):1377-1386
唇鱼骨和间鱼骨均为分布较广的初级淡水鱼类,是理想的亲缘地理研究材料;且两者形态特征较为相似,不易鉴别,故两者的分布记述和物种有效性存在争议.为了解我国南部唇鱼骨和间鱼骨的群体遗传结构并探讨两者的物种有效性,本研究对8条水系的唇鱼骨和9条水系的间鱼骨共130尾个体的COIND5基因序列片段进行了测定,并对这两个基因的组合序列(2151 bp)进行了分析.结果表明: 在130尾个体的COIND5基因组合序列中,共有196个核苷酸变异位点,共检测出50个单倍型,单倍型多样性为0.964,核苷酸多样性为0.019,遗传多样性较高.基于COIND5基因组合序列构建的 NJ 树显示,所有种群可分为两支,支系Ⅰ包含了韩江和九龙江的全部单倍型以及瓯江的部分单倍型,余下的单倍型组成了支系Ⅱ.两支系间的遗传距离为0.036,而唇鱼骨与间鱼骨之间的遗传距离为0.027.单倍型网络图表明,韩江、九龙江种群和其他水系种群分化较大;漠阳江种群由海南岛种群扩散而来;海南岛各种群及漠阳江种群的单倍型分支与珠江水系单倍型的分支之间的亲缘关系较近,与长江水系单倍型分支之间的亲缘关系则较远;湘江、桂江和柳江之间的亲缘关系较近.AMOVA分析结果显示,地理区之间的变异约占71.2%,地理区内种群间变异约占16.6%,种群内的变异占12.2%,表明其遗传分化主要来自地理区之间.错配分析及中性检验结果显示,全部种群、唇鱼骨种群、间鱼骨种群、支系Ⅰ和支系Ⅱ在历史上均没有发生过明显的扩张.  相似文献   

13.
Darren Curnoe   《HOMO》2008,59(2):123-147
The southern African early Homo assemblage continues to make important contributions to understanding the systematics, adaptations and evolutionary history of the human genus. However, the taxonomy of this sample is in a state of flux. This study examines the size and shape of the mandibular bodies of Swartkrans SK 15 and SK 45 comparing them with variation in two early Homo taxa (H. habilis sensu lato and H. sapiens erectus). The research aims to clarify their phenetic affinities and systematics through univariate statistics, inferential testing and multivariate analysis employing size (Log-transformed) and shape (Mosimann variables). Neither of them strongly resembles H. habilis sensu lato or H. sapiens erectus, rather, they probably sample a novel species of Homo not seen in East Africa. Moreover, there is considerable morphological variability within the Swartkrans sample and the possibility of more than one novel species being sampled at this site cannot be excluded.  相似文献   

14.
The tube building polychaete Hydroides elegans Haswell was found living attached to colonies of the arborescent bryozoan Bugula neritina (L.) in Port Shelter, Hong Kong. Field data collected during the period of January through May 1996, showed that H. elegans density reached 77.6 individuals of H. elegans per g wet weight of B. neritina. Density of H. elegans on B. neritina at depths from the surface to 0.5 m was lower than that at depths below 1 m. In January–March, when there were no H. elegans settling on PVC plates or found on natural substrata, numbers on B. neritina were ca. 5 per g wet weight. H. elegans settled on B. neritina and grew rapidly as mean diameter of tubes increased from 605 μm in February to 936 μm in March. In laboratory experiments, larvae of H. elegans settled and metamorphosed on branches of B. neritina and on the bottom of dishes containing B. neritina leachate. Compounds extracted from the leachate of B. neritina induced 74% of H. elegans larvae to metamorphose at a concentration of 16 μg/ml seawater, compared to 5% in dishes containing only filtered seawater (controls). Metabolites from the leachate of B. neritina which were bound to amberlite XAD-2, indicating they are lipophilic in nature, induced over 70% metamorphosis in H. elegans larvae at 56 μg/ml seawater. A biofilm from one of four strains of bacterial isolates associated with the surface of B. neritina induced low levels of metamorphosis in H. elegans larvae, while other bacterial isolates were detrimental to the survival of juvenile H. elegans. Field experiments further demonstrated that H. elegans settled preferentially on Phytagel discs embedded with whole extracts of B. neritina over control Phytagel discs. Metabolites from B. neritina deterred feeding on alginate pellets by assemblages of local fishes in field assays. Metabolites originating from B. neritina, bacteria colonizing B. neritina, and the complex structure of B. neritina contributed to the recruitment of H. elegans to B. neritina surfaces. Hydroides elegans may gain a refuge from predation by associating with B. neritina colonies both from its structural and chemical attributes.  相似文献   

15.
Horizontal starch gel electrophoresis was used to examine genetic diversity within and differences between one population each of two morphologically different species of Haworthia, namely H. pumila and H. herbacea. Twenty-five leaf samples of each species were surveyed for 24 proteins of which 13 were useful for routine analysis, and gene products of 16 protein coding loci revealed genetic variation at 7 (43.8%) thereof in both species. Values of 1.63 (± 0.20) and 1.56 (± 0.18) were obtained for the mean number of alleles per locus and the average heterozygosity per locus was calculated at 0.168 (± 0.058) and 0.144 (± 0.048) for H. herbacea and H. pumila respectively. The malate dehydrogenase-2 locus is a potential genetic marker to identify the species studied electrophoretically. The mean genotypic distance index between the populations studied was 0.184, an indication of large degree of differentiation between the species. These values are much higher than values obtained for other members of the Aloaceae, showing that normal levels of genetic variation can be expected in at least some succulent monocotyledons.  相似文献   

16.
The interaction between Trypanosoma congolense and Haemonchus contortus was studied in 5 groups of 8 Djallonké sheep. Two groups received a single infection with either H. contortus or T. congolense, and 2 groups were infected with T. congolense followed by H. contortus (TH) or vice versa (HT). One group was kept as uninfected controls. Mortality due to infection was observed only in the dual infection groups. In the TH group, the effects were more acute whereas in the HT group they were more chronic. No significant differences in weight gain could be demonstrated between infected and control groups. Djallonké sheep are able to withstand a single infection with either T. congolense or H. contortus, which confirms their trypanotolerant nature and provides preliminary indication of resistance against helminth infections. However, when exposed to successive infections with both parasites, some of the animals lose this tolerance.  相似文献   

17.
Three diploid taxa – Hieracium transylvanicum (subgenus Hieracium), Hieracium caespitosum subsp. brevipilum and Hieracium pavichii (subgenus Pilosella) – from five natural Bulgarian populations were investigated embryologically. The peculiarities of the male and female gametophytes, embryo- and endospermogenesis were established in each species. The results suggest that the species propagate sexually as expected from their diploid chromosome number. However, some forms of apomixis have also been observed, e.g. somatic apospory and integumental embryony in H. pavichii. The presence of apomixis in a diploid taxon shows that polyploidy is not an obligatory prerequisite for apomixis and the two phenomena are independent. The embryological plasticity detected in H. pavichii and H. transylvanicum suggests they may have higher opportunities for adaptation and successful reproduction.  相似文献   

18.
Several procedures have been proposed to assess structural and functional characteristics of cryopreserved ram semen but none so far have yielded consistent relationships with in vivo fertility. The objectives of this study were to evaluate several sperm function tests as potential markers of in vivo ram fertility (determined by pregnancy rate in ewes) using frozen-thawed semen. In experiment 1, frozen-thawed straws (n=3 per ram) of semen from three high and three low fertility rams were assessed using fluorescent microscopy for (1) progressive motility, (2) viability and, (3) acrosomal status. In experiment 2, frozen-thawed straws (n=3 per ram) of semen from 18 rams of known fertility were analysed using either computer-assisted sperm analysis (CASA) for eight motion characteristics or flow cytometric staining for: (1) viability and acrosomal status, (2) plasma membrane status and capacitation-like changes, and (3) live cells following an osmotic resistance test (ORT). In experiment 3, platelet-activating factor (PAF) was isolated from straws (n=2 per ram) of semen using high-pressure liquid chromatography (HPLC) and quantified using HPLC-tandem mass spectrometry for 18 rams. In experiment 1, no association was found between motility, viability (% live) or acrosomal status (% damaged, % intact and % reacted) and in vivo fertility. In experiment 2, no correlation was found between motility (CASA), viability (% live), acrosomal status (% live, % live intact and % reacted), capacitation status (% capacitated, % non-capacitated), plasma membrane stability (% dead) and % live cells following ORT and ram in vivo fertility. In experiment 3, there was no relationship between PAF content in spermatozoa and ram fertility. In conclusion, we were unable to relate the in vivo fertility of rams with in vitro functional tests of their frozen-thawed semen and suggest that the fertility of a given semen sample cannot easily be quantified using available in vitro tests.  相似文献   

19.
Maike Isermann   《Flora》2008,203(4):273-280
The study analysed the effects of shrub expansion on vegetation composition and plant species diversity in coastal grey dunes on the North Sea island Spiekeroog, comparing Rosa rugosa and Hippophaë rhamnoides. Species composition was recorded in plots of two spatial scales, 1 and 16 m2, considering the full range of shrub cover from less than 10 to almost 100%. Although R. rugosa and H. rhamnoides established and spread in the same grey dune environment, the vegetation of the two shrubland types was much different. While the H. rhamnoides plots were relatively species-rich, characterised by remnant grey dune vegetation with many small, often annual, light-demanding species except in the densest shrubs, the R. rugosa plots were clearly species-poorer due to the loss of many typical grey dune species, including only few shade-tolerant taxa. The total number of species, the number of herbaceous species and of species typical for grasslands decreased with increasing cover of H. rhamnoides and R. rugosa at both spatial scales. For the number of shrubs and shrubland species, hardly any significant effects of shrub cover were observed in R. rugosa, while there were positive effects in H. rhamnoides. Both the Shannon index and evenness decreased with increasing cover of the two shrub species at both spatial scales. Here, the decline in species diversity was more improved in R. rugosa than in H. rhamnoides.  相似文献   

20.
《Small Ruminant Research》2010,88(1-3):111-115
Pasteurellosis is one of the most prevalent diseases of sheep, but the involvement of Pasteurellae in genital pathology of rams has been described rarely. One hundred and eighty-four rams showing palpable lesions in testes, epididymides or scrotum were submitted to bacteriological studies, and seven mature rams found infected with bacterial species belonging to the Pasteurella cluster (i.e., Mannheimia, Pasteurella and Bibersteinia (M/P/B)). The M/P/B cultures obtained were pure and/or heavy, and were confirmed after necropsy in the five M/P/B infected rams that could be slaughtered for further pathological examinations. Pasteurella multocida infected rams exhibited fibrinous exudate and generalized adhesions between the vaginal and the external scrotal layers. Testicular atrophy and epididymal sperm granulomas were also evident in these rams. Microscopically, epithelial hyperplasia with intraepithelial cysts, fibrosis and spermatic granulomas were present in the epididymis, while testis showed sperm stasis foci, microcalcifications and fibrosis. Mannheimia haemolytica infected rams showed severe unilateral epididymitis and testicular atrophy, being microscopically similar to the lesions found in P. multocida infected rams. The ram found infected with B. threalosi had severe unilateral lesions in testis, epididymis and scrotum. Microscopically, abscesses in epididymis and testis, and severe fibrosis and interstitial round cells infiltrates in testis were observed. Further studies should be conducted to determine properly the role played by the Pasteurella cluster in the pathogenesis of genital lesions in rams.  相似文献   

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