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21.
Peter B. Best 《African Zoology》2013,48(2):181-185
For most of the year, Meyer’s parrots in the Okavango Delta do not form large feeding flocks, and groups larger than two or three are probably the result of opportunistic aggregation at favoured food items after dispersion from communal roosts. Communal roosting likely does not facilitate flocking unless the food resources are close to the roost site, but may function in anti-predator defence. Meyer’s parrots appear to be dependent on riverine forest, Acacia-Combretum marginal woodland and mopane woodland for roost sites in the Okavango Delta. They aggregated more during the breeding season due to their specialist nutritional requirements, and female dependence on food provisioning by the male parrots. Meyer’s parrots may be sedentary in the Okavango Delta, but the possibility of limited local movements in other areas (especially the Zimbabwean highlands) should be investigated. 相似文献
22.
Summary An equine model of acute non‐immune inflammation has been developed to facilitate studies of the inflammatory process and the actions of novel anti‐inflammatory drugs. Five polyester sponge strips soaked in sterile 2% carrageenin solution were placed in subcutaneous pouches prepared under local anaesthesia in the necks of conscious ponies. Serial removal of the strips and harvesting of the exudate enabled studies to be made of the cellular, biochemical and mediator aspects of the localised, acute inflammation, and the heat generated by the lesion was monitored by infra‐red thermometry. Maximal concentrations of the eicosanoids 6‐keto‐prostaglandin F1α, thromboxane B2 and leukotriene B, occurred at 9 h, whereas leukocyte numbers, lactate dehydrogenase (LDH) and total protein concentrations were greatest at 24 h. Lesional skin temperature was increased by approximately 4°C throughout the 24 h period. The novel anti‐inflammatory agent BW540C, administered orally at a dose‐rate of 20 mg/kg, did not affect leukocyte infiltration or the concentrations of protein, LDH and eicosanoids in exudate but serum thromboxane B2 levels were reduced. Skin temperature rises were greater in drug‐treated animals. It is concluded that higher doses of BW540C will be required for a clinically useful anti‐inflammatory action in horses. 相似文献
23.
以甘肃天祝地区3个牧场所产的白牦牛乳为研究对象,采用气相色谱-质谱联用检测方法,测定3个牧场所产白牦牛乳中脂肪酸含量,比较在枯草期、枯草末期、返青期、青草期4个时期及不同胎次的白牦牛所产牦牛乳中脂肪酸的构成及含量.结果表明:3个牧场白牦牛乳中乳脂肪酸含量差异不显著(P>0.05);1~5胎次母白牦牛乳中脂肪酸含量差异不显著(P>0.05).枯草期、枯草末期、返青期、青草期4个时期白牦牛乳中饱和脂肪酸(SFA)、不饱和脂肪酸(USFA)含量比值分别为1.86、1.75、1.62、1.32.随着气温的升高及牧草的成熟,白牦牛乳中饱和脂肪酸含量逐渐降低,而不饱和脂肪酸的含量逐渐升高. 相似文献
24.
通过招商引资壮大雅安市现有乳品加工企业的能力与水平,带动奶业基地发展;建立奶业协会,破除当前条块分割、体制不顺等问题,提高农民养奶牛奶羊的组织化程度;建设奶业高种园区,提高科技贡献率,充分利用雅安发展奶业得天独厚的优越条件及大好机遇,超常规跨越式发展,使雅安市成为四川奶业强市. 相似文献
25.
Plasma N‐terminal pro‐B‐type natriuretic peptide concentration in healthy retired racing Greyhounds 下载免费PDF全文
26.
Christiana M. Glover Lisa M. Miller Noel O. Dybdal Alfonso Lopez Wendy M. Duckett Dianne McFarlane 《Journal of Equine Veterinary Science》2009
The objective of this study was to describe the histopathologic changes observed in extrapituitary organs as well as the pituitary glands of horses with pituitary pars intermedia dysfunction (PPID). Adrenal gland, thyroid gland, liver, lung, kidney, heart, and pituitary gland from 32 horses with clinical and histologic evidence of PPID and 20 control horses were reviewed histologically. Ten of the control horses were aged animals (≥15 years), allowing those changes attributed to age to be identified. In addition to previously reported changes in adrenal gland and liver, an association was established between PPID and several extrapituitary histopathologic changes, namely bronchiolitis, proliferative glomerulopathy, and myocardial lipofuscinosis and fibrosis. The potential biologic significance of these changes is discussed and, although the retrospective design of the current study precludes establishment of causal relationships between the observed extrapituitary changes and PPID, these findings suggest that further investigations are warranted. 相似文献
27.
28.
植物种间关联研究对揭示植物对生境变化的响应及植被演替机制具有重要意义。运用2×2列联表、2χ检验方法对群落草本植物优势种进行总体相关性和种对间的联结性检验,应用Spearman秩相关系数刻画种对间的数量变化关系,对太行山中段植物群落草本层中重要值较高的32个优势种群、496个种对间的关联性进行定量研究。结果表明,太行山中段草本植物优势种整体上多呈现正关联,群落处于较稳定的演替阶段。其中2χ检验结果有75个种对呈极显著正关联,74个种对呈显著正关联,只有20个种对为不显著的负关联。Spearman秩相关分析结果有43个种对呈极显著相关,79个种对呈显著相关,只有6对为不显著的负相关。对生境要求相同或相似的种对表现出显著的正关联。χ2检验呈显著、极显著相关的种对数多于秩相关分析。 相似文献
29.
A 12‐year‐old Paint‐Arab mare was admitted for evaluation of a penetrating chest laceration at the thoracic inlet. The left brachiocephalic muscle was transected and the recurrent laryngeal nerve was traumatised. Subsequent to the injury, the horse developed Horner's syndrome on the left side of the neck and face, Grade IV left laryngeal hemiplegia, dysphagia, cough and subcutaneous emphysema. The defect was closed in multiple layers. Antimicrobial and antiinflammatory therapy was instituted along with local wound care. The mare remained bright and responsive and the wound healed normally. The mare showed no signs of respiratory distress. Dysphagia and ptosis persisted at 30 days post trauma. 相似文献
30.
鸡肾型传染性支气管炎组织病理学变化规律的研究 总被引:1,自引:3,他引:1
为制造疾病模型便于防治鸡肾型传支。将1日龄健康雏鸡70只分为A、B、C 3组(试验组、对照组和感染组),试验组人工接种IBV肾型毒株,感染组晚1 d放入试验组内混养,常规饲养管理,每日4次观察接毒后的临床症状,同时定期剖检病鸡和病死鸡,取多脏器固定于10%福尔马林液中、石蜡切片、HE染色,显微镜下观察组织病理学变化,按严重程度标+~++++后记录并标明曲线。结果表明,在整个试验过程中肾脏的病理变化最为严重并且持续时间较长,从第2天开始出现病变,并持续到第20天;其次是肺脏,病变出现在第5~16天;肝脏和肺脏的病变时间相同只是程度轻一些;心脏的病变出现在第6~13天。1 d后,感染组也出现相似的病理变化,说明此病的传染性很强。 相似文献