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991.
Current study was conducted to identify constituents of Taxus wallichiana Zucc. that might be responsible for its folk use in anti-inflammatory conditions. Taxusabietane A was isolated from the bark extract of Taxus wallichiana Zucc. Taxusabietane A was analyzed for in-vitro and in-vivo anti-inflammatory activities using Lipoxygenase (LOX) inhibition assay and carrageenan-induced paw edema model. Taxusabietane A revealed considerable LOX inhibitory activity with the IC50 value being 57 ± 0.31. Standard compound Baicalein showed the IC50 value being 22.1 ± 0.03 μM. Taxusabietane A also showed significant (5 and 10 mg/kg) anti-inflammatory activity induced by carrageenan. However, this study highlighted the potential of Taxusabietane A to be further explored as a new lead compound for management of conditions associated with inflammation.  相似文献   
992.
Tropical Animal Health and Production - The aim of the study was to assess the effect of feeding the same diet to different breeds of chickens and at different ages on fatty acid (FA) composition...  相似文献   
993.
Mastitis (intramammary inflammation) caused by infectious pathogens is still considered a devastating condition of dairy animals affecting animal welfare as well as economically incurring huge losses to the dairy industry by means of decreased production performance and increased culling rates. Bovine mastitis is the inflammation of the mammary glands/udder of bovines, caused by bacterial pathogens, in most cases. Routine diagnosis is based on clinical and subclinical forms of the disease. This underlines the significance of early and rapid identification/detection of etiological agents at the farm level, for which several diagnostic techniques have been developed. Therapeutic regimens such as antibiotics, immunotherapy, bacteriocins, bacteriophages, antimicrobial peptides, probiotics, stem cell therapy, native secretory factors, nutritional, dry cow and lactation therapy, genetic selection, herbs, and nanoparticle technology-based therapy have been evaluated for their efficacy in the treatment of mastitis. Even though several strategies have been developed over the years for the purpose of managing both clinical and subclinical forms of mastitis, all of them lacked the efficacy to eliminate the associated etiological agent when used as a monotherapy. Further, research has to be directed towards the development of new therapeutic agents/techniques that can both replace conventional techniques and also solve the problem of emerging antibiotic resistance. The objective of the present review is to describe the etiological agents, pathogenesis, and diagnosis in brief along with an extensive discussion on the advances in the treatment and management of mastitis, which would help safeguard the health of dairy animals.  相似文献   
994.
Brucellosis not only represents an important health restraint on livestock but also causes high economic losses in many developing countries worldwide. Despite considerable efforts made for the control of brucellosis, the disease is still spreading in many regions (such as the Middle East) where it represents one of the most important health hazards impacting both animals and humans. The present review aims to investigate the efficacy of veterinary control programs regarding brucellosis, with a special focus on current prevention, control, and eradication approaches. The reasons for unsuccessful control programs such as the absence of highly effective vaccines and non-certified bulls are also debated, to understand why the prevalence of brucellosis in livestock is not decreasing in many areas despite considerable efforts taken to date. The importance of governmental and regional investment in brucellosis control remains one of the main limiting factors owing to the limited budget allocated to tackle this disease. In this context, one health concept has generated novel comprehensive approaches with multiple economic implications across the livestock industry and public health. However, the implementation of such global preventive strategies appears to be a key issue for many endemic and low-income countries. According to the collected data, epidemiological contexts including management and trade systems along with well-defined agro-ecological zones should be evaluated in brucellosis endemic countries to improve milk production and to enhance the sustainability of the livestock sector at both national and regional levels.  相似文献   
995.
This study aimed to comprehensively evaluate the effects of glycerine supplementation at various concentrations on performance, rumen fermentation, blood metabolites and product characteristics of beef and dairy cattle in vivo by using a quantitative meta-analysis approach. Meta-analysis was performed by integrating a total of 52 studies from 39 articles and 182 treatments into a database. Data were constructed into an intact database and did not distinguish between beef and dairy cattle, except for the parameters of production performance and product characteristics. Data summarized were analysed by using a statistical meta-analysis that employed a fixed effect of glycerine supplementation level and a random effect of various studies for both beef and dairy cattle. Significance of an effect was stated at the probability level of p < .05, and p < .1 was considered as a tendency of significant. Results revealed that there was a linear decrease on dry matter intake (p < .01) and daily gain (p < .05) of beef cattle with the increasing levels of glycerine supplementation. Glycerine supplementation did not decrease milk production of lactating dairy cows. Molar proportion of acetate in the rumen was decreased (p < .001), whereas propionate and butyrate proportions were increased (both at p < .001) by glycerine supplementation. Generally, glycerine did not change nutrient digestibility except that it reduced fibre digestibility (p < .001). Glycerine supplementation linearly lowered triglyceride and NEFA concentrations (both at p < .05) in the blood serum, but not other blood metabolites. Glycerine tended to linearly increase (p < .1) carcass percentage in beef cattle. Increasing dietary glycerine levels decreased milk fat (p < .01) but elevated milk protein (p < .001). Glycerine tended to increase milk lactose (p < .1) by following a quadratic pattern. The proportion of MUFA was increased quadratically by glycerine supplementation (p < .05), whereas glycerine tended to decrease SFA by following a quadratic pattern (p < .1).  相似文献   
996.
Improving water use efficiency in rice irrigation through wet-seeding   总被引:1,自引:0,他引:1  
Since the early-1960's, when modern rice production technologies became available, more than 90% of the total irrigation water developed in south and southeast Asia is used for rice culture. But currently rice culture is highly inefficient in water use. As fresh water availability for agriculuture is becoming increasingly scarce, greater efficiency of water use in rice culture is deemed essential. Past experience indicates that effective implementation of water-efficient irrigation methods in rice farms within public sector irrigation systems is restricted by the difficulty of controlling water deliveries and distribution, and establishing a water charge system based on the actual amount of water used by farmers. Clearly, a rice production method that is inherently less water-requiring, or more water-efficient, would have an advantage over the traditional method in this respect. Recent studies conducted in the Philippines indicate that wet-seeded rice culture is superior to the traditional transplanted rice culture in terms of water efficiency. Other advantages of wet-seeded rice culture include its greater drought tolerance, less labor requirement for crop establishment and weed control, and higher returns from rice farming. This paper presents a comparative study of wet-seeded and transplanted rice cultures focusing on these aspects.  相似文献   
997.
A rotational water supply system is designed to deliver a constant flow of water among irrigators along a tertiary canal. Under the existing rotational system in Pakistan transmission losses along the canal are not considered. A constant time per unit irrigated area is allocated to all the farmers regardless of their location along the canal. This results in decreasing volumes of water delivered to downstream farmers. A variable time model is developed which allocates more time to the downstream farmers to deliver a constant volume of water per unit area to all the farmers in the command area of a tertiary unit.  相似文献   
998.
In this research we explore the potential of precision surface irrigation to improve irrigation performance under the warabandi system prevalent in the Indus Basin Irrigation System. Data on field dimensions, field slopes along with characteristic soil infiltration properties and outlet discharge were collected through a survey of a sample tertiary unit of Maira Branch Canal, Khyber Pakhtunkhwa Province, Pakistan. The performance of all fields in the tertiary unit was analysed and reported in aggregate, with detailed results of one field presented for illustration. The objective is to determine the optimum field layout, defined as the number of border strips, for the observed field characteristics to maximize performance. The results indicate that performance improvement is relatively easily achievable through changes in field layout within current irrigation services. Estimated application efficiency is sensitive to the selected depth of application, and it is important that a practical depth of application is selected. We recommend a depth of application of 50 mm and show how this is achievable and leads to a low quarter distribution uniformity of 0.750 and an application efficiency of 80 %. We also explore the feasibility of a 10-day warabandi rather than the 7-day warabandi and show that there is no significant change in the performance under a 10-day warabandi.  相似文献   
999.
Extensive subsurface drainage system was installed in districtMardan in the North West Frontier Provinceof Pakistan in 1987 to control increasingwater logging and salinity problems due tocanal irrigation. Several recentlycompleted fields studies have indicatedthat subsurface drainage system hasenormously lowered watertable in certainareas due to extensive drainage network. Therefore, a study of controlled subsurfacedrainage technique was initiated in MardanScarp area to observe the temporal andspatial variations in water table depths ofthis specific case under various modes ofcanal irrigation and monsoon rains. Twoartificially drained areas, consisting of40 ha and 160 ha respectively, werecontrolled and selected for extensivemonitoring. A total of 98 observationswells (7.6 cm dia. and 4.1 m depth) wereinstalled in between lateral drains toobserve water table fluctuation. Theresults of this study are very interesting.Each of the two areas monitored in thestudy behaved differently. It was observedthat in one of the areas design water tabledepth at 1.1 m was maintained with properfunctioning of the controlled techniqueapplied to the subsurface drainage system. The results from this area showed that 25to 55% of the time throughout the yearachieved this objective whereas in thesecond area desired water table could notbe maintained and water table depth in thisarea remained between 2.0 to 2.7 m causingunnecessary water stress to plants. Alsoit was observed that watertable in theformer area is mostly controlled by thefunctional behavior of the irrigationcanal. In addition, the proper functioningof controlled techniques in subsurfacedrainage system supplemented veryefficiently to retain the groundwater levelto the optimal limits in dry season and tothe design ones in the others for timelyneeds of the crops. Also rainfalls havesignificant impact on the spatial andtemporal behaviors of water table depths inboth the areas during the monsoon season.  相似文献   
1000.
Based on different surveys, dairy farmers are concerned about extensive use of exogenous oxytocin in buffaloes, which is being held responsible for reproductive problems including irregular oestrous cycle and delayed ovulation. For these concerns, effects of oxytocin injection on postpartum follicular dynamics, postpartum oestrous interval (PEI), oestrous length, the interval from onset of estrus to ovulation and blood progesterone (P4) were studied in Nili-Ravi buffaloes. For this purpose, 23 animals within 1 week after calving were randomly divided into three groups: without oxytocin (CON; n = 7), 10 i.u. oxytocin (LOW; n = 8), 30 i.u. oxytocin – (HIGH; n = 8) and used to record the PEI for the study period of 154 days. At subsequent estrus, three buffaloes from each group (not served) were selected randomly to monitor two cycles for 6 weeks. Transrectal ultrasonography was performed to evaluate follicular and corpus luteum (CL) development, and blood sampling was done for progesterone (P4) analysis. These results revealed that postpartum oestrous interval (PEI) decreased significantly in oxytocin-treated groups. The number of small, medium and total follicles on the left ovary was significantly higher in the HIGH group. However, an overall number of small and total follicles on both right and left ovaries was significantly higher in CON and HIGH groups. On the other hand, there was no difference in the number of follicles on the right ovary among all treatment groups. The same was true for the size of pre-ovulatory follicles, CL, P4 concentrations and oestrous cycle length. The intervals from onset of estrus to ovulation and from standing estrus to ovulation were increased considerably in the HIGH group. It is concluded that exogenous oxytocin administration resulted in the shortening of PEI but triggered a delay in ovulation. Moreover, a higher dose of oxytocin could stimulate the growth of small, medium, and total follicles in postpartum Nili-Ravi buffaloes.  相似文献   
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