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排序方式: 共有549条查询结果,搜索用时 15 毫秒
61.
Uterus didelphys is a rare congenital abnormality of the reproductive tract. Although it occurs in various species, there are no published reports describing pregnancy outcome in association with this abnormality. Herein we describe a case of successful unilateral singleton pregnancy in a ewe incidentally found to have uterus didelphys during the course of a biomedical research study. The pregnancy was established using assisted reproductive techniques and interrupted in late gestation, at which point the abnormality was identified. Serial ultrasound assessment of foetal biometry revealed a normal foetal growth trajectory. Despite a 45% reduction in placentome number, total placentome weight was near normal secondary to compensatory placentome growth and development. To our knowledge, this is the first detailed report of normal foetal growth in an animal with uterus didelphys and illustrates the ability of the ovine placenta to adapt to a reduced number of placentomes and maintain foetal nutrient supply. 相似文献
62.
Marta Salgueiro Alves Anabela Pereira Cludia Vicente Manuel Mota Isabel Henriques 《Forest Pathology》2019,49(6)
In this study, we characterized the diversity of Pseudomonas associated with Bursaphelenchus xylophilus, its insect vector (Monochamus galloprovincialis) and its host (Pinus pinaster), by a culture‐independent approach using rpoD clone libraries. Clone libraries of Pseudomonas rpoD were obtained from B. xylophilus, M. galloprovincialis and infected P. pinaster. Most M. galloprovincialis and B. xylophilus sequences grouped together in the P. fluorescens group. Genes related to xenobiotics degradation and phenylacetate synthesis were present in the genomes of the type strains closely related to sequences retrieved from the nematode libraries. Results demonstrated that the nematode, during its life stages inside the tree, maintains a diverse Pseudomonas community that is closely related to the one associated with the insect vector. These bacteria might contribute to degradation of xenobiotics and tree weakening during the nematode tree infection. 相似文献
63.
Ballester-Sánchez Jaime Gil Jose Vicente Haros Claudia Monika Fernández-Espinar María Teresa 《Plant foods for human nutrition (Dordrecht, Netherlands)》2019,74(2):185-191
Plant Foods for Human Nutrition - Interest in quinoa as a functional food ingredient is currently emerging. The flours from white, red and black quinoa seeds were analysed in terms of total... 相似文献
64.
Bovine tuberculosis (bTB) is caused by Mycobacterium bovis and closely related mycobacteria of the Mycobacterium tuberculosis complex. They have an extensive host range and may cause zoonotic TB. A major obstacle to bTB eradication in livestock is the implication of wildlife in the natural cycle of the pathogen. The identification of wildlife reservoir hosts is crucial for the implementation of effective control measures. The European wild boar (Sus scrofa) is frequently considered a spillover or dead end host rather than a true reservoir, and scientific evidence is conflicting outside Mediterranean Spain. The aim of this review is to update current scientific evidence of the wild boar as a TB reservoir and to underline those aspects that need further research. Evidences supporting that wild boar is a TB reservoir host include: (i) presence of common M. tuberculosis complex genotypes in wild boar, domestic and wild animals and humans, (ii) high prevalence of M. bovis among wild boar in estates fenced for decades in complete absence of contact with domestic livestock, and other wild ungulates (iii) TB lesions are frequently seen in thoracic lymph nodes and lungs, suggesting that respiratory infection and excretion may occur, and (iv) extensive tuberculous lesions in more than one anatomical region occur in a high proportion of juvenile wild boar that probably represents the main source of mycobacterial excretion. Hence, epidemiological, pathological and microbiological evidence strongly suggests that, at least in Spanish Mediterranean ecosystems, wild boar are able to maintain TB infection in the wild and are most probably able to transmit the disease to other species, acting as a true wildlife reservoir. These results expand the list of wildlife species that act as natural reservoirs of TB in different parts of the world and suggest the need to control the infection in wild boar populations for the complete eradication of the disease in Spain. 相似文献
65.
Fernandez-de-Mera IG Vicente J Hofle U Rodriguez O Gaspar-Lopez E Gortazar C 《New Zealand veterinary journal》2008,56(2):71-73
AIM: To determine if there are sex- or age-related differences in the increase in skinfold thickness in response to the mitogen phytohaemagglutinin (PHA) in red deer. METHODS: One dose of 250 mug PHA was injected intradermally in the right side of the neck, and phosphate buffered saline (PBS) was injected at a second site as a control, in 110 (51 males and 59 females) captive Iberian red deer (Cervus elaphus hispanicus), ranging in age from 21 months to > or =5 years. Skinfold thicknesses were measured immediately before and 72 h following injection. RESULTS: There was a significant effect of gender on the average increase in skinfold thickness; males had greater increases (8.8 (SEM 0.57) mm) than females (4.23 (SEM 0.39) mm) after correcting for other confounding variables. No age-related differences were evident, but differences between sexes were more marked with increasing age. CONCLUSIONS AND CLINICAL RELEVANCE: Effects of gender, probably due to differences in energetic and reproductive constraints in red deer, should be taken into account when interpreting skinfold-test data, both in ecology and in the control of tuberculosis (Tb). Males tend to have a thicker skin than females, so skinfold increase relative to the thickness of the skin, rather than skinfold increase per se, should be used as a more appropriate measure of skinfold increase. This may also have clinical relevance in the interpretation of tuberculin skin testing. 相似文献
66.
67.
J.S. Vicente R. Lavara F. Lavara F. Marco-Jimnez M.P. Viudes-de-Castro 《Livestock Science》2008,115(2-3):153-157
Rabbit farmers and insemination centres have established new requirements relating to males (genetic, nutritional and environmental factors) and rabbit insemination techniques. The aim of this study was to evaluate buserelin acetate on the reproductive performance of nulliparous, multiparous lactating and multiparous non-lactating does inseminated on three commercial farms. Two thousand two hundred and three commercial crossbred does belonging to three commercial farms were inseminated with pooled semen from males of two selected meat lines; R line (UPV rabbit selection centres, Spain) in farms 1 and 2, and PS Hyplus 59 line (Grimaud Frère, France) on farm 3. Ejaculates from 12–20 males from each line were pooled and diluted to twelve million sperm per millilitre by adding TRIS–citrate-extender. Diluted semen from each male line was split into two fractions, the first without buserelin acetate added to semen (Control group) and the second fraction was supplemented with 10 μg of buserelin acetate per millilitre (Buserelin group). Receptive females (red colour of vulvar lips) were inseminated with 0.5 mL using a standard plastic curved pipette. Artificial insemination with semen extended with buserelin resulted in lower pregnancy and kindling rates irrespective of the physiological status of females or the farm (78.7% and 76.0% vs 85.8% and 83.4%, buserelin extender group and control respectively, P < 0.01), although does from both treatment groups had a similar litter sizes (10.4 and 9.6 total and alive born, respectively). This study opened up new prospects for changing rabbit insemination procedures. 相似文献
68.
Effects of low‐density lipoproteins as additive on quality parameters and oxidative stress following cryopreservation of mithun (Bos frontalis) spermatozoa 下载免费PDF全文
P Perumal SK Srivastava SK Ghosh KK Baruah S Bag JS Rajoria K Kumar C Rajkhowa M Pande N Srivastava 《Reproduction in domestic animals》2016,51(5):708-716
Artificial breeding of mithun poses several challenges including lack of standard protocol for cryopreservation of spermatozoa. This is further complicated by harmful effects of hen's egg yolk (EY) as additive in extender. Purified low‐density lipoproteins (LDL) extracted from EY have been shown as beneficial over EY extender for long‐term semen storage in several species. This investigation explored use of LDL versus EY on semen quality and oxidative stress following freezing–thawing of spermatozoa. A total of 25 of 50 ejaculates based on biophysical parameters were selected for the experiment. After diluting with the Tris‐citrate‐glycerol (TCG) extender, each sample was split into three equal aliquots: Group I, control, EY; Group II and Group III contained 8% and 10% purified LDL, respectively. Frozen–thawed samples were evaluated for motility parameters (progressive, and in the bovine cervical mucus penetration test [BCMPT]), viability, sperm and nuclear abnormality, acrosome integrity, and enzymatic (leakage of intracellular contents) and biochemical (oxidative stress) profiles and in vitro fertility (IVF) assay. Study revealed a significant (p < .05) improvement in viability, sperm and nuclear abnormality, acrosome integrity, motility (progressive and in cervical mucus), cholesterol content, and reduction in the leakage of intracellular enzymes in Group II. Moreover, intactness of acrosome and biochemical membranes was protected significantly (p < .05) in addition to significant (p < .05) improvement in binding per cent and binding index in IVF assay in extender containing 8% LDL. These results demonstrate that although cryopreservation of mithun's spermatozoa in EY was comparable with other species, addition of 8% LDL holds a clear advantage over EY or 10% LDL. 相似文献
69.
de la Fuente J Ruybal P Mtshali MS Naranjo V Shuqing L Mangold AJ Rodríguez SD Jiménez R Vicente J Moretta R Torina A Almazán C Mbati PM de Echaide ST Farber M Rosario-Cruz R Gortazar C Kocan KM 《Veterinary microbiology》2007,119(2-4):382-390
Anaplasma marginale is a tick-borne pathogen of cattle that causes the disease bovine anaplasmosis worldwide. Major surface proteins (MSPs) are involved in host-pathogen and tick-pathogen interactions and have been used as markers for the genetic characterization of A. marginale strains and phylogenetic studies. MSP1a is involved in the adhesion and transmission of A. marginale by ticks and varies among geographic strains in the number and sequence of amino-terminal tandem repeats. The aim of this study was to characterize the genetic diversity of A. marginale strains collected from countries in North and South America, Europe, Asia, Africa and Australia, inclusive of all continents. In this study, we characterized 131 strains of A. marginale using 79 MSP1a repeat sequences. These results corroborated the genetic heterogeneity of A. marginale strains in endemic regions worldwide. The phylogenetic analyses of MSP1a repeat sequences did not result in clusters according to the geographic origin of A. marginale strains but provided phylogeographic information. Seventy-eight percent of the MSP1a repeat sequences were present in strains from a single geographic region. Strong (> or =80%) support was found for clusters containing sequences from Italian, Spanish, Chinese, Argentinean and South American strains. The phylogenetic analyses of MSP1a repeat sequences suggested tick-pathogen co-evolution and provided evidence of multiple introductions of A. marginale strains from various geographic locations worldwide. These results contribute to the understanding of the genetic diversity and evolution of A. marginale and tick-pathogen interactions. 相似文献
70.
Mtshali MS de la Fuente J Ruybal P Kocan KM Vicente J Mbati PA Shkap V Blouin EF Mohale NE Moloi TP Spickett AM Latif AA 《Zoonoses and public health》2007,54(1):23-30
Bovine anaplasmosis, caused by the tick-borne rickettsia Anaplasma marginale, is endemic in South Africa and results in considerable economic loss to the cattle industry. This study was designed to characterize strains of A. marginale at the molecular level from cattle raised in communal and commercial farms in the north-eastern and south-western regions of the Free State Province, South Africa, that varied in rainfall and vegetation. Seroprevalence to A. marginale was determined in 755 cattle by an Anaplasma spp. competitive enzyme-linked immunosorbent assay and ranged from 44% to 98% and was similar in both regions. While Anaplasma centrale was not targeted in this study, A. marginale infections were identified by species-specific msp1alpha polymerase chain reaction in 129 of 215 of the samples studied. Similar genetic diversity of A. marginale strains was found in both the north-eastern and south-western regions. The sequences of 29 A. marginalemsp1alpha amplicons from South African strains revealed considerable genetic diversity providing 14 new repeat sequences. However, 42% of MSP1a repeat sequences were not unique to this region. These results indicated the presence of common genotypes between South African, American and European strains of A. marginale. Cattle movement between different parts of South Africa was suggested by the presence of identical A. marginale MSP1a genotypes in north-eastern and south-western regions of the Free State Province. Control strategies for anaplasmosis in South Africa should therefore be designed to be protective against genetically heterogeneous strains of A. marginale. 相似文献