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171.
Summary A pilot health monitoring system was started in 1990 to develop statistically valid data for use in estimating the disease frequencies in dairy cattle and buffaloes. This paper presents the design of the monitoring programme and frequencies of selected diseases. Eighty herds were selected with typical livestock management practices of the farmers in the area. Veterinary assistants visited the farms once a month for 12 months to collect livestock inventory, production, disease and preventive treatment data. The incidence density method was used as a measure of disease frequency.In adults, breeding problems, mastitis and gastro-intestinal problems were the highest reported conditions. Respiratory problems were the commonest in young stock. The calves of both species frequently had gastro-intestinal and respiratory disease conditions. Most of the calf crop of both species were lost within the first 3 months of life.
Monitoreo De Problemas De Salud Bovina En Hatos Lecheros Pequenos En El Territorio Capital De Islamabad
Resumen Se inició un sistema de monitoreo piloto en 1990, con el propósito de desarrollar datos estadísticos válidos para estimar la frecuencia de enfermedades en ganado lechero y en búfalos. Este artículo presenta el diseño del programa de monitoreo y la frecuencia de las enfermedades seleccionadas. Se seleccionaron ochenta hatos con el manejo típico de los ganaderos del área. Los veterinarios visitaron las fincas una vez al mes durante 12 meses para colectar información. El método de densidad en la incidencia fue usado para medir la frecuencia de enfermedades.En adultos, las condiciones más frecuentemente encontradas fueron problemas de fertilidad, mastitis y problemas gastrointestinales. Las afecciones respiratorias fueron el común denominador en jóvenes. Los terneros de ambas especies se encontraron frecuentemente con problemas gastrointestinales y respiratorios, conjuntamente, siendo la mortalidad extremadamente alta en los 3 primeros meses de vida para ambas especies.

Gestion Des Problemes De Sante Bovine De Petits Troupeaux Laitiers Sur Le Territoire De Islamabad: Schema, Donnees Et Frequences De La Maladie
Résumé Un système pilote de gestion de la santé a débuté en 1990 pour développer des données statistiquement valables pour être utilisées dans l'estimation de la fréquence des maladies de bovins laitiers et de buffles. Cet article présente le schéma du programme de gestion et les fréquences des maladies sélectionnées. Quatre vingt troupeaux ont été choisis; leur élevage était conduit selon la méthode propre aux fermiers de la région. Des assistants vétérinaires ont visité les fermes une fois par mois durant 12 mois pour relever les données sur l'inventaire du bétail, la production, les maladies et les traitements préventifs. L'importance de l'incidence a été utilisée comme méthode pour mesurer la fréquence des maladies. Chez les adultes, les problèmes prédominants dans les conditions indiquées concernaient la reproduction, les mammites et des troubles gastrointestinaux. Les problèmes respiratoires étaient les plus communs chez le jeune bétail. Les veaux des deux espèces présentaient fréquemment des troubles respiratoires et gastrointestinaux. La majorité de la production de veaux des deux espèces étaient perdue dans les trois premiers mois de vie.
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Growth and photochemical response of triazine-susceptible and -resistant rutabaga ‘Laurentian’ genotypes to cyanazine (chloro-s-triazine) and metribuzin (methylthio-as-triazine) were evaluated. The young seedlings of the susceptible rutabaga were killed when cyanazine or metribuzin were applied either pre- or post-emergence. The triazine-resistant rutabaga, however, displayed a differential response to these herbicides. Metribuzin applied pre-emergence killed the seedlings at 0.4 kg ha?1, and at 0.2 kg ha?1 the growth was severely affected. Cyanazine even at higher rates applied pre- or post-emergence failed to inhibit growth in these plants.Chlorophyll fluorescence in leaf sections at the cotyledonary, 2-leaf and 4-leaf stages in the susceptible plants increased by 130 and 172% in response to 10?5 M cyanazine and metribuzin, respectively, suggesting that Photosystem II reactions in these plants were severely impaired. In resistant plants, there was little or no leaf chlorophyll fluorescence (LCF) increase at this herbicide concentration. However, at 10?4 M cyanazine and metribuzin, the LCF in resistant plants increased significantly and the increase was greater in response to metribuzin (86%) than to cyanazine (51%). This indicates that with these triazine-resistant genotypes, metribuzin is relatively more potent and at high rates is capable of interfering with photosynthesis.  相似文献   
174.
Eight clones of monoclonal antibodies (Mabs) to Nipah virus (NV) were produced against formalin-inactivated NV antigens. They reacted positive by indirect immunofluorescent antibody test, and one of them also demonstrated virus neutralizing activity. They were classified into six different types based on their biological properties. These Mabs will be useful for immunodiagnosis of NV infections in animals and further research studies involving the genomes and proteins of NV.  相似文献   
175.
The fruits of the date palm (Phoenix dactylifera) are consumed throughout the world and are an important part of the diet in the Middle East. Dates at the rutab and tamar maturity and ripening stages contain a wide array of phenolic antioxidants, but little is known about the composition of phenolic compounds in dates at the khalal stage of ripening. In the current study, the flavonoid glycoside and procyanidin compositions of dates of the cultivar Deglet Noor harvested at the khalal stage of maturity were characterized using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI/MS/MS). Procyanidin oligomers through decamers were identified in extracts of these dates. Higher molecular weight polymers, undecamers through heptadecamers, were also apparent from mass spectra. Thirteen flavonoid glycosides of luteolin, quercetin, and apigenin, 19 when considering isomeric forms, were also identified. Mass spectra indicate that both methylated and sulfated forms of luteolin and quercetin are present as mono-, di-, and triglycosylated conjugates whereas apigenin is present as only the diglycoside. LC-ESI/MS/MS spectra indicate that quercetin and luteolin formed primarily O-glycosidic linkages whereas apigenin is present as the C-glycoside.  相似文献   
176.
In this work we identified specific bovine leukocytes that were bound by the Mannheimia haemolytica adhesin molecule (MhA) and the biological effect on the leukocytes. Histochemical staining and flow cytometry showed that MhA bind neutrophils (90%) and monocytes (5%). MhA induced an oxidative response in purified neutrophils; this effect was 1.5-fold higher than the effect observed with control cells activated with Zymosan. Cellular binding by MhA was inhibited with GlcNAc and its oligomers, as well as by glycoproteins containing tri- and tetra-antennary N-glycosydically linked glycans. MhA-induced oxidative burst was significantly inhibited by GlcNAc, iodoacetamide, superoxide dismutase, and piroxicam (p<0.05). Our findings suggest that among bovine leukocytes, neutrophils are the main target for MhA, inducing production of oxidative radicals by non-opsonic mechanism that seem to play an important role in tissue damage during mannheimiosis.  相似文献   
177.
Imidacloprid has been used as a key insecticide for controlling sucking insect pests of cotton, whereas Spodoptera litura also has been indirectly exposed to this insecticide in Pakistan. To evaluate the risk of resistance evolution and to develop a better resistance management strategy, a field collected population was selected with imidacloprid in the laboratory. Thereafter, fitness cost, realized heritability and cross resistance of imidacloprid resistance in S. litura were investigated. After 14 generations of selection with imidacloprid, S. litura developed a 137.48-fold resistance to the insecticide. Bioassay revealed that this strain showed cross-resistance to acetamiprid (RR 8.52) and a little to lamdacyhalothrin (1.92) but negative cross-resistance was found to methomyl (−0.19). The resistant strain had a relative fitness of 0.38, with substantially lower rates of larval survival, larval duration, male pupal duration, development time, emergence rate of healthy adults, fecundity, hatchability, and prolonged larval and pupal duration. Mean relative growth rate of the larvae, intrinsic rate of population increase, and biotic potential was lower for the selected populations. The estimated realized heritability (h2) of imidacloprid resistance was 0.15 in the resistant strain of S. litura. Development of the resistance may cost significant fitness for the resistant population. This study provided valuable information for further understanding the impact of imidacloprid resistance on physiological parameters of S. litura and for facilitating the development of resistance management strategies.  相似文献   
178.
根据塔克拉玛干沙漠北缘荒漠过渡带哈德、肖塘2个试验点的风、温梯度观测数据,利用风速比法计算了中性大气层结、无风沙运动条件的空气动力学粗糙度[WTBX](z0),并分析探讨z0[WTBZ]与下垫面状况、大气稳定度及风速的相互关系。结果表明:哈德、肖塘中性条件下z0的取值范围分别为 1.81×10-11~1.20×10-3 m,1.00×10-11~1.65×10-3 m,平均值为2.70×10-5 m 和6.05×10-5 m,与平坦沙面的值较为接近;z0随下垫面性质变化明显;空气动力学粗糙度总体上随着理查逊数(Ri)增大而变大,但又呈现出一定的离散程度;空气动力学粗糙度与2 m高度风速呈显著的负指数关系;大气稳定度对空气动力学粗糙度的影响作用有待于进一步确定。   相似文献   
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