Validation of the specificity and sensitivity of species-specific primers that provide a reliable molecular diagnostic for <Emphasis Type="Italic">Xiphinema diversicaudatum</Emphasis>, <Emphasis Type="Italic">X. index</Emphasis> and <Emphasis Type="Italic">X. vuittenezi</Emphasis>

Xiphinema diversicaudatum and X. index are vector nematode species of economic importance in viticulture regions as they can transmit Arabis Mosaic, Grapevine Fanleaf and Strawberry Latent Ringspot viruses to grapevine. Wang et al. (2003) designed species-specific diagnostic primers from ribosomal genes for both these vector species as well as a vector and a non-vector species X. italiae and X. vuittenezi, respectively. Our study aimed to confirm the specificity and determine the sensitivity and reliability of the primers for the two vector species, X. diversicaudatumand X. indexwhen challenged with closely related longidorid species and general nematode communities typical of vineyard soil. With one exception, no PCR product was observed when the primers were tested against six Longidorus, one Paralongidorus and one Xiphinema non-target species. Occasionally (three out of eight replicate PCR reactions) a weak PCR product was noted when primers for X. index were tested with L. elongatus. Furthermore, when challenged with a range of non-target nematode species comprising the nematode community typical of viticulture soil, no PCR product was amplified. An experimental dilution series of extracted DNA rigorously demonstrated that DNA from an equivalent single specimen of the target virus-vector species, X. diversicaudatum and/or X. index, could be detected amongst 1000 equivalent non-targetX. vuittenezi. Also, extracted DNA from an equivalent single target specimen was detected when added to DNA extracted from the overall soil nematode community. The primers were assessed further by using serial mixtures of actual nematodes rather than extracted DNA to simulate field soil. Using this method, a single target nematode could be detected amongst 200 non-target specimens. Given their specificity, sensitivity and reliability, it appears that these diagnostic primers will be of great benefit to phytosanitary/quarantine services related to the viticulture industry.     

植物化感作用影响因素的再认识

土壤养分、酶、微生物、本底特性,根茬还田、水分、植物根系、种植体系和种植模式与化感作用的互作关系,表明这些因子可通过对土壤养分有效性、微生物种群结构、土壤酶活性和化感物质浓度的影响而对化感作用产生直接或间接影响,这些可为通过化感作用途径构建高效农田生态系统提供新的思路.     

鹰嘴紫云英头茬草生产性能的研究

通过对杨凌地区生长的鹰嘴紫云英（Astragalus cicer L.）的株高、株长、产量、草层结构、鲜干比、茎叶比等的研究表明：生长第二年第一茬初花期时刈割的鹰嘴紫云英平均株高达57 cm,株长达102 cm,鲜草产量达47 077.6 kg/hm^2,干草产量8 702.0 kg/hm^2,其茎、叶主要分布在0～40cm的草层中,茎、叶鲜重分别占到总重量的52.39%和31.88%,鲜干比为5.41：1,茎叶比为1.47：1,属典型的下繁型牧草,具产草量高、营养丰富、牧草品质好等优点,是值得推广的优良牧草.     

山羊胎期肺发育的形态学研究

对3～22周龄山羊胎儿肺进行了肉眼、光镜和透射电镜观察，结果表明：1．7～22周龄山羊胎儿肺的外部形态与胎龄无关，肺的外部形态以左二右四叶者为多见．肺的叶间裂和右肺副裂常不完整，以浆膜、肺组织或混合性组织(肺组织及浆膜)融合；2．山羊胎儿肺的发育分为5个时期：胚胎期(3～5周)肺芽分支形成主支气管，主支气管长度不断增长并萌芽出叶支气管，均衬以假复层柱状上皮。腺状期(6～12周)以支气管树发育为主，小支气管衬以假复层和／或单层柱状上皮；终蕾呈腺状，上皮细胞由假复层柱状逐渐变为单层柱状，胞核向细胞顶端移行；终蕾上皮细胞游离面可见短小的微绒毛；线粒体、粗面内质网及核糖体随着胎龄增加而逐渐增多，它们均位于细胞顶部。小管期(13～14周)以呼吸部发育为主，原始肺泡开始形成，呼吸性细支气管衬以未分化的立方上皮；终蕾腺状结构逐渐消失，终蕾上皮细胞由高矮不等的单层柱状上皮逐渐演变为立方形的原始肺泡上皮；细胞游离面可见较多的微绒毛，胞质内线粒体、粗面内质网及核糖体较发达。囊状期(第15周)呼吸部发育显著，肺内细支气管及其末端呈现出“充气”状态；部分原始肺泡上皮细胞分化为扁平的肺泡Ⅰ型细胞和立方形的肺泡Ⅱ型细胞；Ⅱ型细胞内出现嗜锇小体。肺泡期(16～22周)以肺泡的形成和分化为主，更多的肺泡上皮分化为扁平的肺泡Ⅰ型细胞和立方形的肺泡Ⅱ型细胞。此期，毛细血管内皮与部分肺泡上皮贴近，可将肺泡上皮细胞区分为3种：Ⅰ型细胞，呈矮柱状或椭圆形，胞质中有较明显的核糖体、扩张内质网及变性线粒体；形成了由Ⅰ型细胞一基膜一内皮细胞组成的气血屏障。Ⅱ型细胞，胞质内含丰富的嗜锇板层小体和核糖体，内质网扩张呈大小不一的泡状，多泡体出现，线粒体膨大变性，细胞游离面可见少数微绒毛。Ⅲ型细胞，为未分化细胞，呈立方形，胞体较小，胞核相对较大，呈圆或椭圆形，胞质少，呈带状．电子密度低，细胞器少。     

水氮供应对地下滴灌紫花苜蓿生长特征及草地小气候的影响

为探讨不同水氮处理条件下紫花苜蓿生长状况与草地小气候特征的关系,以2年生紫花苜蓿“巨能7号”为研究对象,采用田间试验和室内分析相结合的方法,研究了宁夏引黄灌区地下滴灌条件下不同滴灌量和施氮量处理下紫花苜蓿生长特征和草地小气候的变化。结果表明:1)滴灌量和施氮量对紫花苜蓿的株高、叶面积和鲜草产量都有显著的影响,表现为紫花苜蓿的株高、叶面积和鲜草产量均随滴灌量和施氮量的增加而增加,当施氮量增加到一定值时,继续增施氮肥,其鲜草产量增产效果在不同滴灌量处理下表现出不同的趋势。2)与不施氮处理相比,增施氮肥降低了紫花苜蓿株间空气温度、浅层土层温度和株间光照强度,而增加了群体内部空气相对湿度。3)不同滴灌量对紫花苜蓿的生长微环境的调节作用不同,随着滴灌量的增加,紫花苜蓿群体相对湿度逐渐提高,而紫花苜蓿株间气温和浅层土层温度降温效应越明显。4)紫花苜蓿生育期间株高与叶面积、草产量和群体内部相对湿度呈极显著正相关(P<0.01),与群体内光照强度、株间气温、浅层土壤温度呈极显著负相关(P<0.01)。合理减少滴灌量和施氮量不仅能维持紫花苜蓿良好的生长特征,而且能提高鲜草产量和改善草地生态环境条件。本研究旨在为紫花苜蓿群体微环境生态因子的改善及高产优质栽培措施提供科学依据。     

A review on breeding and genetic strategies in Iranian buffaloes (<Emphasis Type="Italic">Bubalus bubalis</Emphasis>)

The aim of current study was to review breeding progress and update information on genetic strategies in Iranian buffaloes. Iranian buffalo is one of the vital domestic animals throughout north, north-west, south and south-west of Iran with measurable characteristics both in milk and meat production. The species plays an important role in rural economy of the country due to its unique characteristics such as resistance to diseases and parasites, having long productive lifespan and showing higher capability of consuming low-quality forage. In Iran, total production of milk and meat devoted to buffaloes are 293,000 and 24,700 tons, respectively. Selection activities and milk yield recording are carrying out by the central government through the Animal Breeding Centre of Iran. The main breeding activities of Iranian buffaloes included the estimation of genetic parameters and genetic trends for performance traits using different models and methods, estimation of economic values and selection criteria and analysis of population structure. Incorporating different aspects of dairy buffalo management together with improved housing, nutrition, breeding and milking, is known to produce significant improvements in buffalo production. Therefore, identifying genetic potential of Iranian buffaloes, selection of superior breeds, improving nutritional management and reproduction and developing the education and increasing the skills of practical breeders can be useful in order to enhance the performance and profitability of Iranian buffaloes.     

Prevalence of <Emphasis Type="Italic">Haemonchus contortus</Emphasis> infection in sheep slaughtered at Jimma town municipal abattoir,Ethiopia

Haemonchus contortus is a parasite of major economic importance of most sheep-rearing areas of the world. A cross-sectional study was conducted from November 2015 to March 2016 with objectives of determining the prevalence and associated risk factors of Haemonchus contortus infection in sheep slaughtered at Jimma town municipal abattoir, Ethiopia. Of the total 7000 sheep slaughtered during the study time period, 384 sheep were randomly selected and examined for parasites. The overall prevalence of Haemonchus contortus infection was 264 (68.75%). Infection rate of poor body condition animals was significantly (P?=?0.000) higher than good body conditioned animals. The mean packed cell volume (PCV) values (%) of parasitemic and aparasitemic sheep were 23.73?±?3.7 SD and 37.66?±?4.736 SD, respectively. The prevalence in adult sheep (>?1 year) was insignificantly (P?=?0.653) higher than that of young sheep (≤?1 year). The highest prevalence was recorded in sheep that originated from Seka district (73.3%) and the lowest in Kersa district (63.4%) with non-significant variation (P?=?0.691). The highest monthly mean worm burdens and prevalence of Haemonchus contortus infection were recorded in November and lowest in March. The current study revealed that Haemonchus contortus infection is an important and common parasitic disease and requires special attention to its control.     

Can treatment of <Emphasis Type="Italic">Brachiaria decumbens</Emphasis> (signal grass) improve its utilisation in the diet in small ruminants?—a review

Brachiaria decumbens is an extremely productive tropical grass due to its aggressive growth habit and its adaptation to a varied range of soil types and environments. As a result of the vast availability, treated B. decumbens demonstrates as a promising local material that could be utilised as an improved diet for sheep and goats. Despite the fact that the grass significantly increases weight gains in grazing farm animals, there were many reports of general ill-thrift and sporadic outbreaks of photosensitivity in livestock due to the toxic compound of steroidal saponin found in B. decumbens. Ensiling and haymaking were found to be effective in removing toxin and undesirable compounds in the grass. Biological treatments using urea, activated charcoal, polyethylene glycol, and effective microorganisms were found to be useful in anti-nutritional factor deactivation and improving the nutritive values of feedstuffs. Besides, oral administration of phenobarbitone showed some degree of protection in sheep that fed on B. decumbens pasture. In this review, we aim to determine the effect of B. decumbens toxicity and possible treatment methods on the grass to be used as an improved diet for small ruminant.     

Stem cell factor supports migration in canine mesenchymal stem cells

Adult Mesenchymal Stem Cells (MSC) are cells that can be defined as multipotent cells able to differentiate into diverse lineages, under appropriate conditions. These cells have been widely used in regenerative medicine, both in preclinical and clinical settings. Initially discovered in bone marrow, MSC can now be isolated from a wide spectrum of adult and foetal tissues. Studies to evaluate the therapeutic potential of these cells are based on their ability to arrive to damaged tissues. In this paper we have done a comparative study analyzing proliferation, surface markers and OCT4, SOX9, RUNX2, PPARG genes expression in MSC cells from Bone marrow (BMMSC) and Adipose tissue (ASC). We also analyzed the role of Stem Cell Factor (SCF) on MSC proliferation and on ASCs metalloproteinases MMP-2, MMP-9 secretion. Healthy dogs were used as BMMSC donors, and ASC were collected from omentum during elective ovariohysterectomy surgery. Both cell types were cultured in IMDM medium with or without SCF, 10% Dog Serum (DS), and incubated at 38 °C with 5% CO2. Growth of BMMSCs and ASCs was exponential until 25–30 days. Flow citometry of MSCs revealed positive results for CD90 and negative for CD34, CD45 and MCH-II. Genes were evaluated by RT-PCR and metalloproteinases by zymografy. Our findings indicate morphological and immunological similarities as well as expression of genes from both origins on analyzed cells. Furthermore, SCF did not affect proliferation of MSCs, however it up-regulated MMP-2 and MMP-9 secretion in ASCs. These results suggest that metalloproteinases are possibly essential molecules pivoting migration.     

Risk factors associated with feline urolithiasis

Urinary tract diseases are among the main reasons for consultation in veterinary clinics and hospitals. It affects animals of any age, breed and gender. Among the diseases that affect this system, urolithiasis is the second largest cause of clinical signs compatible with feline urinary tract disease. The term urolithiasis refers to the presence of uroliths in any region of the urinary tract, but it is more commonly seen in the bladder and urethra. Uroliths are classified based on the type of mineral present in their composition, therefore, quantitative and qualitative analyzes are important for a better therapeutic approach. The animals may suffer from the disease and be asymptomatic, or show nonspecific clinical signs, making the diagnosis difficult. The disease should not be seen as a single problem, but as a consequence of various disorders. As dietary, metabolic, genetic and infectious causes, as well as factors that potentiate the chance of development of uroliths such as breed, age, sex, age range, obesity, sedentary lifestyle, geographic region and climate. Thus, the knowledge of the factors that influence the formation of uroliths, as well as the understanding of the pathophysiology, are key elements for better alternatives of therapy and prevention. The recognition of these factors helps to identify susceptible populations, minimizing exposure and increasing the protection factors, which facilitates the diagnosis and treatment of patients with urolithiasis. The objective of this paper is to present the main risk factors involved in the formation of urinary lithiasis in felines.