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1.
Theileria equi (T. equi) is an obligate intra- and extra-erythrocytic parasite that causes equine theileriosis (ET) in equids. Equine theileriosis is considered a notifiable disease of global significance, a major constraint to the international movement of horses, and endemic in many countries. This disease may be difficult to diagnose, as it can produce variable and nonspecific clinical signs. A cross-sectional study was designed for the molecular characterisation of T. equi and to investigate the associated risk factors of ET accompanied by its consequences on haematological and sero-biochemical parameters. A convenience sampling of 500 blood samples were collected from ET suspect horses from January to December 2017. PCR was performed on all blood samples targeting the 18S rRNA gene of T. equi followed by sequencing; 9% animals tested positive with confirmed sequences. The isolates of this study showed high homology with Cuban, Russian and Brazilian isolates of T. equi (accession numbers KY111762.2 , MG551915.1 and KY952237.1 , respectively). Based on multivariate analysis, the principal risk factors consisted of absence of dogs on the premises and presence of tick infestation. The haemato-biochemical parameters showed a decrease in granulocytes and erythrocytes, and an increase in lymphocytes, monocytes, mean corpuscular volume, mean corpuscular haemoglobin, mean platelet volume, glucose, phosphorus and aspartate aminotransferase in positive horses. This is the first study which identified ET in Punjab (Pakistan) using molecular techniques and risk factors together with the haemato-biochemical variations in horses.  相似文献   
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Agroforestry practices of farming communities are investigated in southern Punjab province, Pakistan. It is hypothesized that rural people of this areas are more inclined than elsewhere in the province to practice agroforestry due to greater profitability than cropping. A landholder survey revealed that the majority of farmers are inclined to plant trees on their land. Low accessibility of institutional credit is a constraint for both agroforestry farmers (AF) and non-agroforestry farmers. However, among AF respondents only 24% were found to need credit for agroforestry practice, as against nearly 76% for crop production. Mostly farmers were found to have positive perceptions regarding agroforestry practice, because they understand the multiple benefits from growing trees, compared with cropping where farmers face various constraints, including poor access to credit, natural hazards, and little support from local authorities. Further, effort to sensitize farmers that growing trees has multiple benefits compared to only cultivation of field crops can bring about change in farmer’s perceptions and attitudes in the Indus River basin, resulting in motivation for agroforestry adoption.  相似文献   
4.
1. Nuclear magnetic resonance imaging (MRI) was used to assess the advantages of the technique in determining the size (volume) and shape of the Pectoralis muscle ( Pectoralis major and minor) in broiler chickens, non-invasively and in vivo . 2. The imaging was performed using a Spectroscopy Imaging System 2.0 Tesla/31 cm bore imaging spectrometer. Three-dimensional reconstruction of transverse images was used to estimate the size of the Pectoralis muscle of chickens ranging in body weight from 362 to 1643 g. 3. Regression analysis resulted in R 2 values of 0.92 and 0.99 for the relationship between Pectoralis muscle weight, body weight and muscle volume, respectively. 4. It is concluded that MRI and 3-dimensional image reconstruction may be used to estimate the Pectoralis muscle size and shape. This may be readily extended to monitor the influence of various factors on the growth and development of specific organs and tissues in the body.  相似文献   
5.
Summary Two pairs of genes indicated by H P 1 and H A 2 appear to play a part in the genetic control of pubescence of leaves in the crosses of Pak51 x Empire Red leaf, L11 x Empire Red leaf, AC134 x Empire Red leaf, AC134 x Acala 1517D and L11 x Acala 1517 D. H P 1 seems to induce hair of sufficient length and density and is completely dominant to h p 1.H A 2 allele, seems to induce hairiness but to a smaller degree. It acts additivily to H P 1 giving profusely hairy plants. H P 1 gene is present in the local varieties Pak51, L11 and AC134 producing hair of such length and density as to confer jassid resistance in them. Compared with these, the exotic types viz., Empire Red leaf and Acala 1517D possess H A 2 giving sparsely hairy plants.The exotic variety Deltapine Smooth leaf possesses another gene, E A, which displays an epistatic effect on H A 2 gene. The gene E A has only a minor effect on the H P 1.Apart from this, the presence of certain intensifying or modifying genes seem to affect the density and length of hair resulting in deviations even in individual groups.M. Sc. Student, Professor and Head, and Reader, respectively of the Dept. of Plant Breeding and Genetics.  相似文献   
6.
ABSTRACT

Organic amendments in the soil perform better than synthetic fertilizers in regards to soil fertility and sustainable crop productivity. Experiments were conducted to compare the effects of organic and synthetic fertilizers on soil fertility and wheat (Triticum aestivum L.) productivity. Soil fertility and protein contents of wheat grains (13.2% and 13.3% during 2005–06 and 2006–07, respectively) were improved by organic amendments. However, synthetic fertilizer (at the rate of 150, 100, and 60 kg ha?1 N, P2O5, and K2O, respectively) applications resulted in the maximum grain yield (4.05 and 4.46 t ha?1 during 2005–06 and 2006–07, respectively). The observed and simulated soil organic carbon (SOC) reasonably agreed during RothC model validation (R 2 = 0.99). Economic analysis showed the maximum net profit and relative increase in income ($729 US ha?1 and 309%, respectively) from inorganic treatment. Application of synthetic fertilizers increased grain yield and farm profit while organic manure enhanced grain quality. The RothC model had potential for determining the SOC in organic farming under arid environment.  相似文献   
7.
Under semiarid subtropical field conditions, denitrification was measured from the arable soil layer of an irrigated wheat–maize cropping system fertilized with urea at 50 or 100 kg N ha–1 year–1 (U50 and U100, respectively), each applied in combination with 8 or 16 t ha–1 year–1 of farmyard manure (FYM) (F8 and F16, respectively). Denitrification was measured by acetylene inhibition/soil core incubation method, also taking into account the N2O entrapped in soil cores. Denitrification loss ranged from 3.7 to 5.7 kg N ha–1 during the growing season of wheat (150 days) and from 14.0 to 30.3 kg N ha–1 during the maize season (60 days). Most (up to 61%) of the loss occurred in a relatively short spell, after the presowing irrigation to maize, when the soil temperature was high and a considerable NO3-N had accumulated during the preceding 4-month fallow; during this irrigation cycle, the lowest denitrification rate was observed in the treatment receiving highest N input (U100+F16), mainly because of the lowest soil respiration rate. Data on soil respiration and denitrification potential revealed that by increasing the mineral N application rate, the organic matter decomposition was accelerated during the wheat-growing season, leaving a lower amount of available C during the following maize season. Denitrification was affected by soil moisture and by soil temperature, the influence of which was either direct, or indirect by controlling the NO3 availability and aerobic soil respiration. Results indicated a substantial denitrification loss from the irrigated wheat–maize cropping system under semiarid subtropical conditions, signifying the need of appropriate fertilizer management practices to reduce this loss.  相似文献   
8.
Summary Four species of amphistomes were recorded from buffaloes in Peshawar region. The incidence of different species was determined. The significance of amphistomes in causing disease is discussed.
Sumario Se registraron cuatro especies de Paramfistomas de bufalos en la región de Peshawar. Se determinó la incidencia de las diferentes especies. Se discute el significado de los amfistomas como causantes de Enfermedates.

Résumé 4 espèces d'amphistomes sont signalées chez les buffles de la région de Peshawar. L'incidence de ces différentes espèces est déterminée. L'importance de ces amphistomes sous l'angle de leur pouvoir pathogène est discutée.
  相似文献   
9.
The study was designed to investigate the effect of cold irrigation water on rice growth and on uptake of N, P, K and Zn applied ca. 50, 20, 35 and 5 mg kg−1 soil, respectively. Cold temperature of irrigation water reduced rice shoot and root dry weight and plant height, significantly compared to hot temperature treatment. Under low temperature stress N was a major rice growth determinant. Increased shoot concentrations of both P and Zn allevated the low temperature stress. The uptake of N, P, K and Zn reduced significantly at low temperature (16.5–20 °C soil and 20–24 °C flood water) compared to high temperature (24.5–27 °C soil and 26.5–29.0 °C), with the strongest effect being noticed for N, followed by P, K and Zn. Application of N, P, K and Zn increased their uptake in rice shoots. Nitrogen and K had synergistic effect on their uptake. Responses to N and K application and their uptake behavior were well marked at higher than at low temperature whereas reverse was true for P and Zn.  相似文献   
10.
土壤活性有机碳测定方法的改良   总被引:3,自引:0,他引:3  
土壤碳库是陆地生态系统中最大的碳库,活性有机碳作为土壤碳库中最活跃的组分,对土壤碳含量的变化和碳排放具有较好的指示作用。目前活性有机碳的测定主要采用333 mmol L-1KMnO_4氧化方法,然而该方法存在诸多不足,需要进行改良。采用改良方法(1:0.2 K_2Cr_2O_7-H_2SO_4)和KMnO_4法测定我国农田生态系统5个长期施肥站点土壤活性有机碳的含量。两种方法测定的土壤活性有机碳含量存在极显著的线性回归关系,且在各地点和施肥处理下均呈极显著的线性关系;改良方法测定的标准误和变异系数都比KMnO_4方法低;并且改良方法所需设备简单、操作简便快速等优点。因此本研究的改良方法与KMnO_4法相比具有一定的优势,可以考虑作为土壤活性有机碳测定的改良方法。  相似文献   
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