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1.
Zhang-Yong Ning Xin-Tao Wu Yan-Fen Cheng Wen-Bao Qi Yu-Fu An Heng Wang Gui-Hong Zhang Shou-Jun Li 《Journal of veterinary science (Suw?n-si, Korea)》2012,13(3):219-222
Reports of influenza A virus infections in dogs has received considerable attention from veterinarians, virologists, and epidemiologists. Interaction between influenza viral hemagglutinin and cell oligosaccharides containing sialic acid residues results in infection. Sialic acids have an α-2,3-linkage to the penultimate galactose in the avian influenza virus receptor and an α-2,6-linkage in the human receptor. To date, there are no detailed data on the tissue distribution or histological features of either type of sialic acid-linked influenza virus receptors in beagle dogs, which are common laboratory animals and pets. We conducted the current study to visualize the in situ tissue distribution of both sialic acid-linked influenza virus receptors in various organs of beagle dogs using Maackia amurensis lectin II and Sambucus nigra agglutinin. Both α-2,3- and α-2,6-sialic acid-linked receptors were detected in the endothelial cells of the respiratory tract and other organs. Endothelial cells of most gastrointestinal organs were negative for α-2,3-sialic acid-linked receptors in the dogs. Our results suggested that these canine organs may be affected by influenza virus infection. The findings from our study will also help evaluate the occurrence and development of influenza virus infections in dogs. 相似文献
2.
The presence and distribution of cannabinoid type 1 and 2 receptors in the mandibular gland: The influence of different physical forms of diets on their expression in piglets
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C. Pirino M. G. Cappai M. Maranesi D. Tomassoni A. Giontella W. Pinna C. Boiti J. Kamphues C. Dall'Aglio 《Journal of animal physiology and animal nutrition》2018,102(2):e870-e876
We explored the expression and cell type distribution of cannabinoid receptors type 1 (CB1) and cannabinoid receptors type 2 (CB2) in the mandibular glands of pigs in relation to different physical forms of the diet. Thirty‐two crossbred growing pigs (ages 5–6 weeks) were randomly allotted to four experimental groups (eight pigs/group) and fed four different physical types of the same diet for 4 weeks: finely ground pellet (FP), coarsely ground meal (CM), coarsely ground pellet (CP) and coarsely ground extruded (CE) with dMEAN of 0.46, 0.88, 0.84 and 0.66 mm respectively. At the end of the feeding trial, the pigs were euthanized and the mandibular gland was collected after dissection. By immunohistochemistry, positive signals for CB1 were found in the cytoplasm of duct epithelial cells of pigs fed CP, FP and CE diets and in the serous cells of mixed acini in pigs fed the coarser CM diet. Positive signals for CB2 were detected in duct epithelial cells and in neurons of ganglia close to major secretory ducts of all pigs. The differential expression and localization of these receptors in response to variable chewing activity due to the type of diet suggest that endocannabinoids may influence the functional activity of the mandibular gland by modifying qualitative and/or quantitative aspects of salivary secretion. 相似文献
3.
Henson KL Alleman AR Kelley LC Mahaffey EA 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2000,29(2):40-46
Abstract: Immunohistochemical techniques were used to examine 29 cases of equine lymphoma for estrogen receptor (ER) and progesterone receptor (PR) expression. The lymphomas examined included T-cell-rich large B-cell lymphomas, B-cell neoplasms, and T-cell lymphomas. The individual cases were also classified according to the anatomic location of the tumors. One normal equine lymph node was also examined for ER and PR expression. All of the cases of equine lymphoma and the normal lymph node were negative for ER. A total of 16/29 (55%) PR-positive lymphomas were identified. Seven of the 12 (58%) T-cell-rich large B-cell lymphomas were positive, 7/11 (64%) B-cell tumors were positive, and 2/6 (33%) T-cell neoplasms were positive. Anatomically, 6/9 (66%) subcutaneous lymphomas were PR positive, 3/5 (60%) intrathoracic lymphomas were positive, 1/4 (25%) intra-abdominal lymphomas were positive, 2/5 (40%) intra-abdominal/intrathoracic lymphomas were positive, 1/2 (50%) upper airway lymphomas were positive, and 3/3 (100%) splenic lymphomas were positive. One case involving abdominal and thoracic tumors and leukemia was negative for PR expression. The normal lymph node contained a low percentage (1.9%) of PR-positive lymphocytes. The presence of PR in neoplastic equine lymphoid tissue indicates that these tumors may be responsive to serum progesterone. Also, identification of PR-positive cells in the normal lymph node suggests that PR may be constitu-tively expressed in normal equine lymphocytes. Further studies are needed to quantify PR levels in normal and malignant equine lymphoid tissue and to determine the usefulness of either progestin or antiprogestin drugs in the management of equine lymphoma. 相似文献
4.
Epidermal growth factor (EGF) receptors were detected in plasma membrane preparations of equine hoof wall laminar tissue at concentrations comparable to that of equine liver. Scatchard analysis of the equilibrium binding data suggested the presence of two classes of EGF binding sites in most of the controls (plasma membranes from clinically normal horses); a high-affinity class and a more numerous low-affinity class. The dissociation constant of the low-affinity class of EGF-specific receptors (KD = 1 x 10(-9)M) is in reasonable agreement with other values established for the EGF receptor. The variability between individual estimates for the KD of the high-affinity receptor class precluded an accurate estimate for those sites. A possible explanation is discussed. The high-affinity binding sites were uniformly absent in plasma membranes prepared from horses affected by chronic laminitis. Autoradiographic analysis localised the EGF receptors primarily to the secondary epidermal laminae, with an apparent greater density over the proliferative basal keratinocytes. Little label was associated with the dermal or the keratinised primary epidermal laminae. Tissue from horses with chronic laminitis had EGF receptors located uniformly over the hyperplastic epidermal keratinocytes. These data suggest that an EGF-mediated response may be involved in the hyperproliferative response that is characteristic of chronic laminitis. 相似文献
5.
Research progress on the role of melatonin and its receptors in animal reproduction: A comprehensive review
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HS Talpur IB Chandio RD Brohi T Worku Z Rehman D Bhattarai F Ullah L JiaJia L Yang 《Reproduction in domestic animals》2018,53(4):831-849
Melatonin and its receptors play a crucial role in the regulation of the animal reproductive process, primarily in follicular development. However, the role that melatonin performs in regulating hormones related with reproduction remains unclear. Melatonin and its receptors are present both in female and male animals’ organs, such as ovaries, heart, brain and liver. Melatonin regulates ovarian actions and is a key mediator of reproductive actions. Melatonin has numerous effects on animal reproduction, such as protection of gametes and embryos, response to clock genes, immune‐neuroendocrine, reconciliation of seasonal variations in immune function, and silence or blockage of genes. The growth ratio of reproductive illnesses in animals has raised a remarkable concern for the government, animal caretakers and farm managers. In order to resolve this challenging issue, it is very necessary to conduct state‐of‐the‐art research on melatonin and its receptors because melatonin has considerable physiognomies. This review article presents a current contemporary research conducted by numerous researchers from the entire world on the role of melatonin and its receptors in animal reproduction, from the year 1985 to the year 2017. Furthermore, this review shows scientific research challenges related to melatonin receptors and their explanations based on the findings of 172 numerous research articles, and also represents significant proficiencies of melatonin in order to show enthusiastic study direction for animal reproduction researchers. 相似文献
6.
H Korkeala 《Acta veterinaria Scandinavica》1979,20(3):438-446
The accumulation and distribution of cadmium (Cd) between cellular subfractions were studied in Cd-resistant Staphylococcus 3719 + and its plasmid-negative Cd-sensitive variant 3719–, grown in media containing 0.01, 0.1 or 50 mg of Cd/litre. In the media containing 0.01 and 0.1 mg of Cd/1 the uptake of Cd by the Gd-resistant S. aureus was significantly less than that by Cd-sensitive S. aureus, both in toto and in terms of the cell wall fractions. Only variant 3719 + grew in the medium containing 50 mg of Cd/1. The finding of a lag phase in the growth of both variants is interpreted to suggest that the resistance is of inducible character, even in the sensitive S. aureus. The mechanism of resistance to Cd could consist of both barrier and clearance functions. 相似文献
7.
N. LUTHERSSON K. HOU NIELSEN P. HARRIS T. D. H. PARKIN 《Equine veterinary journal》2009,41(7):619-624
Reasons for performing study: The prevalence (up to 93% in Thoroughbred racehorses) and severity of equine gastric ulceration syndrome (EGUS) have been correlated with the type of training and associated management practices. However, there have been few reports to confirm these findings in nonracehorses in Europe. Objectives: To describe the prevalence, anatomical distribution, severity and number of gastric ulceration lesions in a population of Danish pleasure horses; and to investigate differences for groups based on age, breed type and workload. Methods: A total of 201 horses not in active race‐training, age 7 months‐27 years, were evaluated, representing 23 different stables from all 5 regions of Denmark. These horses were considered to be healthy by the owner and not on veterinary treatment for EGUS. Endoscopically observed ulcer lesion scores were based on the number present (0–4) and severity (0–5). The presence or absence of ulcers in the glandular and/or nonglandular regions of the stomach was recorded and which site the most severe ulcers were found. Results: The prevalence of EGUS severity score ≥2 was 53%. The most severe lesions were commonly observed at the margo plicatus. Although older horses were not more likely to be affected by clinically significant EGUS they were more likely to have lesions in both the glandular and nonglandular regions. Differences in location of EGUS lesions were identified in different age groups, breed types and in horses exposed to different levels of work. Conclusion and potential relevance: This study confirms that gastric ulceration can be prevalent in a group of apparently clinically normal horses, not in intensive work. Further investigation of reasons for differences in EGUS location between different populations may aid toward the development of novel preventive measures. 相似文献
8.
为检测胰岛素样生长因子(IGFs)及其受体(IGFR)mRNAs在绵羊发情周期早期卵巢、子宫和输卵管中的表达,探讨绵羊胚胎早期发育过程中其发育环境——生殖道中生长因子的表达、分泌及其作用,取绵羊发情周期早期卵巢、子宫和输卵管,经固定、切片、免疫染色,观察IGFs mRNAs的表达和分布情况。同时用RT-PCR技术研究了各组织中IGF-Ⅰ、IGF-Ⅱ、IGF-ⅠR、IGF-ⅡR mRNAs的表达情况。结果表明,IGFs mRNAs在绵羊发情周期早期的卵巢、子宫和输卵管中都有表达,4种因子表达模式相似:在卵巢中,IGFs主要定位于卵泡颗粒细胞,间质细胞亦有少量表达。在输卵管中,上皮细胞免疫染色呈阳性;在子宫中,腺细胞及上皮细胞的阳性信号强于固有层。RT-PCR检测表明IGFs mRNAs在3种组织中均有表达。 相似文献
9.
REASONS FOR PERFORMING STUDY: The acceptance of skin grafts in horses is unpredictable and the final cosmetic result can be disappointing. Besides movement and infection, graft failure is often caused by chronic inflammation, inherently present during second intention healing of limb wounds in horses. In human burns affected by infection and inflammation, the acceptance of the island skin grafts of the modified Meek technique appeared to be better than meshed sheet skin grafts. HYPOTHESIS: The percentage take of Meek micrografts is higher than of other techniques; and rates of both wound contraction and epithelialisation are increased. METHODS: Large traumatic limb wounds of 13 horses healing by second intention were grafted using the modified Meek technique. Photographs of the wounds were taken at set intervals. Wound areas, and areas of acceptance and rejection were determined using a digital image post processor (Scion Image). The percentages of take, wound contraction and epithelialisation were calculated. RESULTS: The initial mean wound area was 7500 mm2. Graft acceptance was mean +/- s.d. 93.7 +/- 5.9%. Wound closure was due to contraction (55.2 +/- 11.1%) and epithelialisation (44.8 +/- 11.1%) and resulted in a 96.7 +/- 3.6% reduction of the initial wound area 29.1 +/- 6 days after grafting. All wounds showed functional and cosmetic healing. CONCLUSIONS: The method for skin grafting in horses achieved higher percentages of take than reported previously and consistent cosmetic and functional results. The grafts increased not only the rate of epithelialisation but also had a strong positive effect on wound contraction, resulting in rapid closure and smaller scars. POTENTIAL RELEVANCE: The modified Meek technique proved to be a novel technique for skin grafting equine wounds in clinical practice, which can be performed easily. The molecular background of the increase of wound contraction by the grafts may provide a clue in the search for medicinal stimulation of wound contraction during second intention healing. 相似文献
10.
Rattanatrai CHAIYASING Takuro ISHIKAWA Katsuhiko WARITA Yoshinao Z. HOSAKA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2021,83(7):1022
This study aimed to investigate the function of estrogen receptors (ERs) in myoregeneration and intermuscular adipogenesis. Ovariectomized (OVX) ERα knockout (KO) mice and ERβ KO mice were used to assess the effect of estrogen on the myoregenerative process. Tibialis anterior muscle was collected on days 7, 10, and 14 after cardiotoxin injection to assess myotube morphology and adipogenesis area. Regenerated myotubes from OVX-ERβ KO mice were consistently smaller in diameter than those from OVX-ERα KO and OVX-wild-type mice, whereas the adipogenesis area of OVX-ERβ KO mice was consistently greater than that of the other types. Therefore, ERβ may be an influential factor in promoting myoregeneration and adipogenesis inhibition compared to ERα. 相似文献
11.
Olkowski AA Wojnarowicz C Chirino-Trejo M Wurtz BM Kumor L 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2005,52(10):517-524
The present study examined several basic attributes of first-line defence mechanisms in the skin as potential factors that may explain the susceptibility of broiler chickens to cellulitis. The variables including structural characteristics of the skin, physicochemical properties and cellular responses to the challenge with pathogens were compared between two categories of chickens, a strain of fast-growing commercial broiler chickens (susceptible to cellulitis) and leghorn chickens (resistant to cellulitis). There were substantial differences between leghorns and broilers with regard to physiological characteristics of the skin. Broiler skin was more amenable to injury and the wound-healing process was slow. Compared with leghorns, the lesions resulting from sub-dermal challenge in broilers were more severe and disseminated over a larger area. Mobilization of phagocytic cells (heterophils and macrophages) in leghorns was brisk even in the areas distant from the site of infection, whereas only few heterophils were recruited in the skin of broilers. The functional competence of heterophils in broilers was inferior when compared with leghorns. Based on the present finding, the predisposition of broilers to cellulitis appears to be primarily associated with the inferior first line of defence of their skin. Broilers in commercial situations may be at higher risk to succumb to even minor infection and eventually develop cellulitis because: (1) structural weaknesses of the skin may predispose broilers to skin injury and thus the risk of skin infection by pathogens is increased; (2) broiler skin surface is more likely to provide a conducive environment for colonization of Escherichia coli; (3) in the event of infection, poor recruitment of phagocytic cells to the site of infection may readily lead to widespread colonization of the tissue by pathogens causing cellulitis and (4) poor functional quality of the phagocytic cells that are mobilized compromise the ability of the host to contain the spread of infection. 相似文献
12.
The equine enteric nervous system — Neuron characterization and distribution in adults and juveniles
D. L. Doxey G. T. Pearson E. M. Milne J. S. Gilmour H. K. Chisholm 《Veterinary research communications》1995,19(6):433-449
A study of myenteric and submucosal plexuses was undertaken in the jejunum and ileum of horses and ponies in which no clinical or pathological evidence of intestinal abnormality was apparent. Complete transverse sections of the intestine, stained by a modified haematoxylin and eosin method, were examined using up to 20 sequential sections per animal. Information was gathered from adult, juvenile and fetal equidae. In adults, the longitudinal muscle layers were thinner than the circular muscle layers and the ileum had thicker layers compared to the jejunum. In adults, the submucosal plexus had more neurons per section than the myenteric plexus by mean ratios of 1:3 in the jejunum and 1:1.9 in the ileum. In juveniles, the ratios were respectively 1:1.8 and 1:1.5 and in the fetus 1:2.5 and 1:1.3. The three-dimensional distribution of neurons in both plexuses varied from animal to animal and no consistent pattern was observed. Groups of neurons contained between one and 42 cells per section examined and their length in a cranio-caudal direction varied from 10 to over, 100 µm. There were few statistical differences observed between the cranial, middle and caudal portions of either the jejunum or the ileum when neuron groups or neuron numbers per section were examined in 10 adult animals.Abbreviations H&E
haematoxylin and eosin
Deceased; formerly of the Moredun Research Institute, 408, Gilmerton Road, Edinburgh, EH17 7JH, UK 相似文献
13.
《Veterinary anaesthesia and analgesia》2017,44(1):127-132
ObjectiveTo evaluate the regional distribution of ventilation in horses during spontaneous breathing and controlled mechanical ventilation (CMV) using electrical impedance tomography (EIT).Study designProspective, experimental case series.AnimalsFour anaesthetized experimental horses.MethodsHorses were anaesthetized with isoflurane in an oxygen-air mixture and medetomidine continuous rate infusion, placed in dorsal recumbency with an EIT belt around the thorax, and allowed to breathe spontaneously until PaCO2 reached 13.3 kPa (100 mmHg), when volume CMV was started. For each horse, the EIT signal was recorded for at least 2 minutes immediately before (T1), and at 30 (n = 3) or 60 (n = 1) minutes after the start of CMV (T2). The centre of ventilation (CoV), dependent silent spaces (DSS) (likely to represent atelectatic lung areas), non-dependent silent spaces (NSS) (likely to represent lung areas with low ventilation) and total ventilated area (TVA) were evaluated. Cardiac output (CO) was measured and venous admixture and oxygen delivery (DO2) were calculated at T1 and T2. Data are presented as median and range.ResultsAfter the initiation of CMV, the CoV moved ventrally towards the non-dependent lung by 10% [from 57.4% (49.6–60.2%) to 48.3% (41.9–54.4%)]. DSS increased [from 4.1% (0.2–13.9%) to 18.7% (7.5–27.5%)], while NSS [21.7% (9.4–29.2%) to 9.9% (1.0–20.7%)] and TVA [920 (699–1051) to 837 (662–961) pixels] decreased. CO, venous admixture and DO2 also decreased.Conclusions and clinical relevanceIn spontaneously breathing anaesthetized horses in dorsal recumbency, ventilation was essentially centred within the dependent dorsal lung regions and moved towards non-dependent ventral regions as soon as CMV was started. This shows a major lack of ventilation in the dependent lung, which may be indicative of atelectasis. 相似文献
14.
REASONS FOR PERFORMING STUDY: Dehydration is a serious welfare concern in horses working in developing countries. Identification of a valid and practical indicator of dehydration would enable more rapid treatment and prevention. OBJECTIVES: To examine changes in bodyweight, clinical and blood parameters during rehydration of working horses, identify a 'gold standard' criterion for dehydration and use this to validate a standardised skin tent test, drinking behaviour and mucous membrane dryness as potential field indicators. METHODS: Fifty horses with a positive skin tent test, working in environmental temperatures of 30-44 degrees C in Pakistan, were rested and offered water to drink ad libitum. Bodyweight, clinical and blood parameters, mucous membrane dryness, drinking behaviour and skin tent duration at 6 anatomical locations were measured at 0, 30, 60, 120, 180, 240 and 300 min. RESULTS: Skin tent duration was affected by side of animal (P = 0.008), anatomical location and coat moisture (both P < 0.001). Younger animals had shorter skin tents at all time points (P = 0.007). There was no significant association between plasma osmolality (P(osm)) or water intake and skin tent duration. Horses with a higher P(osm) drank significantly more water (P < 0.001), and had longer (P < 0.001) and more frequent (P = 0.001) drinking bouts. Neither P(osm) nor water intake affected qualitative and semi-quantitative measurements of mucous membrane dryness significantly. CONCLUSIONS AND POTENTIAL RELEVANCE: The standardised skin tent test and measures of mucous membrane dryness investigated in this study were not valid or repeatable indicators of dehydration when compared with P(osm) as a 'gold standard' criterion. The volume of water consumed and the number and duration of drinking bouts were the most reliable guide to hydration status currently available for mature working horses. Offering palatable water to drink ad libitum provides both the diagnosis and the remedy for dehydration in working horses. 相似文献
15.
Previous studies have shown that the brain is a target of persistent infection with bovine viral diarrhea virus (BVDV) and have demonstrated viral tropism for neurons as well as other endogenous cell types in diverse brain areas. Apart from foci of mild residual inflammation in some postnatal calves, consistent brain lesions, per se, have not been reported. No similar comprehensive studies of the brain have been reported in bovine fetuses. In the current study, 12 BVDV-seronegative heifers were inoculated intranasally with a 2-ml 4.4 log(10) TCID(50)/ml dose of noncytopathic type 2 BVDV at 75 and 175 days of gestation to create persistently and transiently infected fetuses, respectively. In only persistently infected fetuses, encephaloclastic lesions resulting in pseudocysts were observed in the subependymal zone in the region of the median eminence and adjacent corona radiata as well as in the region of the external capsule associated with lenticulostriate arteries. Additionally, areas of rarefaction in white matter were observed at the tips of cerebrocortical gyri and in the external capsule. The distribution of viral antigen was examined by immunohistochemical labeling using the 15C5 anti-BVDV monoclonal antibody. Viral antigen was detected only in calves inoculated at 75 days of gestation, i.e., persistently infected. The pattern of BVDV immunolabeling revealed both similarities and differences compared with previous studies in postnatal calves, suggesting that viral infection in the brain is a dynamic and progressive rather than static process. 相似文献
16.
N. Arcamone L. D’Angelo P. de Girolamo C. Lucini A. Pelagalli L. Castaldo 《Research in veterinary science》2014
This study reports the immunohistochemical localization and distribution of orexin A and B-like and their receptors-like peptides in the gastroenteric tract of chicken. The immunoreactivity is distributed in endocrine cells, nerve fibers and neurons, both in the stomach and intestine, and shows a discrete conformity with the data till now reported for Mammals. Our study suggests a possible participation of orexin-like peptides in the modulation of chicken gastroenteric activities and the preservation of their main distribution compared to Mammals. Western blot analysis has confirmed the presence of prepro-orexin and both receptors in the examined tissues. 相似文献
17.
Martina Mosing Ulrike Auer Paul MacFarlane David Bardell Johannes P. Schramel Stephan H. Böhm Regula Bettschart-Wolfensberger Andreas D. Waldmann 《Veterinary anaesthesia and analgesia》2018,45(1):31-40
Objective
The aim of this study was to evaluate the effect of continuous positive airway pressure (CPAP) on regional distribution of ventilation and dead space in anaesthetized horses.Study design
Randomized, experimental, crossover study.Animals
A total of eight healthy adult horses.Methods
Horses were anaesthetized twice with isoflurane in 50% oxygen and medetomidine as continuous infusion in dorsal recumbency, and administered in random order either CPAP (8 cmH2O) or NO CPAP for 3 hours. Electrical impedance tomography (and volumetric capnography (VCap) measurements were performed every 30 minutes. Lung regions with little ventilation [dependent silent spaces (DSSs) and nondependent silent spaces (NSSs)], centre of ventilation (CoV) and dead space variables, as well as venous admixture were calculated. Statistical analysis was performed using multivariate analysis of variance and Pearson correlation.Results
Data from six horses were statistically analysed. In CPAP, the CoV shifted to dependent parts of the lungs (p < 0.001) and DSSs were significantly smaller (p < 0.001), while no difference was seen in NSSs. Venous admixture was significantly correlated with DSS with the treatment time taken as covariate (p < 0.0001; r = 0.65). No differences were found for any VCap parameters.Conclusions and clinical relevance
In dorsally recumbent anaesthetized horses, CPAP of 8 cmH2O results in redistribution of ventilation towards the dependent lung regions, thereby improving ventilation-perfusion matching. This improvement was not associated with an increase in dead space indicative for a lack in distension of the airways or impairment of alveolar perfusion. 相似文献18.
新疆焉耆盆地黑果枸杞灌丛与根系组成及分布特征 总被引:2,自引:0,他引:2
对新疆焉耆盆地平原盐漠草地中的黑果枸杞(Lycium ruthenicum)灌丛与根系组成及分布特征进行了研究。结果表明,黑果枸杞灌丛由新老株丛构成,常以几近平行的多行排列分布;其根系为根蘖型,主要由水平根及根蘖形成植株的地下垂直茎组成,不定根作为一个特殊组成部分,具有明显的季节性和特定性,仅在7月后参与木质化的水平根和地下垂直茎组成的根系系统上发生;水平根分布于50cm左右深的土层,具有分蘖和继续分生水平根的特性;地下垂直茎具有在地下多级分生的特性。地下生物量占总生物量的平均鲜重比例为33.2%,根系所在的土壤含水量在13.7~19.1%。 相似文献
19.
N. P. De Bernardis K. A. Seabaugh J. Ismay M. Mudge 《Equine Veterinary Education》2019,31(12):659-665
Multiple techniques exist for removal of cystic calculi in the male horse, some of which use a perineal urethrotomy (PU) to facilitate access to the urinary bladder for removal of small uroliths in the standing, sedated horse. These techniques have limited efficacy in the removal of uroliths that have a diameter larger than the PU site, typically 4–5 cm. Pneumatic lithotripsy as reported in this article provides a novel way to fragment these larger uroliths while containing the fragments and protecting the urethra and urinary bladder. Ten geldings and one stallion underwent a lithotripsy procedure to remove one (n = 10) or several (n = 1) uroliths ranging in diameter from 4 to 9 cm. A PU was performed and a laparoscopic retrieval bag was inserted into the urinary bladder through the PU site. The urolith was manipulated into the bag using blind transrectal manipulation or endoscopic guidance and the opening of the bag was exteriorised out of the PU site. A pneumatic lithotrite was used to fragment the stone. When the urolith was adequately fragmented, the fragments were removed by the use of sponge forceps and by flushing the fragments from the bag with obstetrical lube. This was continued until the bag could smoothly be withdrawn from the urinary bladder. All uroliths were successfully removed. The PU sites healed without complication and none of the horses had recurrence of presenting clinical signs. This article also discusses the difference between two types of laparoscopic retrieval bags. Pneumatic impact lithotripsy in combination with a retrieval pouch offers a safe alternative to other methods for removal of cystic calculi in the horse. 相似文献
20.
Reasons for performing study: No previous study compares computed tomography (CT), contrast‐enhanced computed tomography (CECT) and standing low‐field magnetic resonance imaging (LFMRI) to detect lesions in horses with lameness localised to the foot. This study will help clinicians understand the limitations of these techniques. Objectives: To determine if CT, CECT and LFMRI would identify lesions within the distal limb and document discrepancies with lesion distribution and lesion classification. Methods: Lesions in specific structures identified on CT and MR images of feet (31 limbs) from the same horse were reviewed and compared. Distributions of lesions were compared using a Chi‐squared test and techniques analysed using the paired marginal homogeneity test for concordance. Results: Lesions of the deep digital flexor tendon (DDFT) were most common and CT/CECT identified more lesions than LFMRI. Deep digital flexor tendon lesions seen on LFMRI only were frequently distal to the proximal extent of the distal sesamoid and DDFT lesions seen on CT/CECT only were frequently proximal to the distal sesamoid. Lesions identified on LFMRI only were core (23.3%) or splits (43.3%), whereas lesions identified only on CT were abrasions (29.8%), core (15.8%), enlargement (15.8%) or mineralisation (12.3%). Contrast‐enhanced CT improved lesion identification at the DDFT insertion compared to CT and resulted in distal sesamoidean impar ligament and collateral sesamoidean ligament vascular enhancement in 75% of cases. Low‐field MRI and CT/CECT failed to identify soft tissue mineralisation and bone oedema, respectively. Conclusions and potential relevance: Multiple lesions are detected with CT, CECT and LFMRI but there is variability in lesion detection and classification. LFMRI centred only on the podotrochlear apparatus may fail to identify lesions of the pastern or soft tissue mineralisation. Computed tomography may fail to identify DDFT lesions distal to the proximal border of the distal sesamoid. 相似文献