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1.
The Activated Coagulation Time (ACT) was determined on 10 normal cows. Duplicate samples were taken from each cow. The mean ACT was 145 seconds with a range of 120-180 seconds. Standard deviations were 18 and 13 for the first and second sampling, respectively. Repeatability of the ACT was acceptable.  相似文献   
2.
Forage technology has been successfully introduced into smallholder cattle systems in Cambodia as an alternative feed source to the traditional rice straw and native pastures, improving animal nutrition and reducing labour requirements of feeding cattle. Previous research has highlighted the positive impacts of forage technology including improved growth rates of cattle and household time savings. However, further research is required to understand the drivers, challenges and opportunities of forage technology for smallholder cattle households in Cambodia to facilitate widespread adoption and identify areas for further improvement. A survey of forage-growing households (n = 40) in July–September 2016 examined forage technology adoption experiences, including reasons for forage establishment, use of inputs and labour requirements of forage plot maintenance and use of forages (feeding, fattening, sale of grass or seedlings and silage). Time savings was reported as the main driver of forage adoption with household members spending approximately 1 h per day maintaining forages and feeding it to cattle. Water availability was reported as the main challenge to this activity. A small number of households also reported lack of labour, lack of fencing, competition from natural grasses, cost of irrigation and lack of experience as challenges to forage growing. Cattle fattening and sale of cut forage grass and seedlings was not found to be a widespread activity by interviewed households, with 25 and 10% of households reporting use of forages for these activities, respectively. Currently, opportunities exist for these households to better utilise forages through expansion of forage plots and cattle activities, although assistance is required to support these households in addressing current constraints, particularly availability of water, if the sustainability of this feed technology for smallholder cattle household is to be established in Cambodia.  相似文献   
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4.
Dried tansy ragwort containing pyrrolizidine alkaloids was fed as 2.5% of a complete (control) diet to Hereford steers, with and without (basal) a mixture of additives. The additives provided a dietary supplement equivalent to 0.1% ethoxyquin, 1% methionine hydroxy analog, 2% MgO, 2.7 mg of vitamin B6/kg of diet, 50 micrograms of vitamin B12/kg of diet, 0.45 g of folic acid/kg of diet, and 0.2 g of cobalt/kg of diet. The additives did not alter tansy ragwort toxicity substantially, as assessed by liver histologic changes, sulfobromophthalein clearance rate, and serum gamma-glutamyl transpeptidase activity. After 281 days, 1 of 4 steers fed the basal diet was alive, whereas 3 of 4 steers in the basal plus additives group were alive, suggesting some protective activity. The chronic lethal dose of tansy ragwort in steers was 3.6% of initial body weight.  相似文献   
5.
南极半岛海洋气候区的土壤Ⅲ.冻-融作用与水分状况   总被引:1,自引:0,他引:1  
陈杰  龚子同  阮心玲  BlumeHP 《土壤》2004,36(1):5-11
自由水活动在南极海洋性气候区土壤形成与演化过程中发挥极为重要的作用。本文对土壤自由水的来源、冻-融作用、永冻层和活动层动态以及自由水参与下的物质迁移过程等几个方面进行了论述,讨论了上述不同过程的影响因素以及土壤发生学意义,指出以土壤水形态转化和自由水活动为基础的土壤过程具有显著的微域性特点,是决定本区土壤发生类型与分布模式的重要因素之一。  相似文献   
6.
HP Lin  CY Mou 《Science (New York, N.Y.)》1996,273(5276):765-768
The recently discovered mesoporous aluminosilicate MCM-41 consists of hexagonal arrays of nanometer-sized cylindrical pores. It is shown that this material can be synthesized by cooperative condensation of silicate and cylindrical cationic micelles. Careful control of the surfactant-water content and the rate of condensation of silica at high alkalinity resulted in hollow tubules 0.3 to 3 micrometers in diameter. The wall of the tubules consisted of coaxial cylindrical pores, nanometers in size, that are characteristic of those of MCM-41. The formation of this higher order structure may take place through a liquid crystal phase transformation mechanism involving an anisotropic membrane-to-tubule phase change. The hierarchical organization of this "tubules-within-a-tubule" particle texture is similar to that of the frustules of marine diatoms.  相似文献   
7.
During recent years, Yersinia enterocolitica has been isolated from humans and various animal species in connection with intestinal disorders, such as acute ileitis and appendicitis. Cases of septicaemia, polyarthritis and erythema nodosum have also been described (Mollaret & Destombes 1964, Nilehn 1969, Winblad 1969, Lassen 1972, Langford 1972). Y. enterocolitica has been isolated most frequently from chinchillas and hares, but sporadic isolations from deer, cow, horse, rabbit, goat and dog have been reported (Langford, Krogstad et al. 1972). In Norway, an outbreak of the disease in a goat herd is the only described case of yersiniosis among animal species (Krogstad et al.). A case of chronic enteritis in a dog from which Y. enterocolitica was isolated is presented in the following.  相似文献   
8.
An oral vitamin E absorption test used in human beings was modified for use in horses. The most appropriate techniques with which to measure gastrointestinal tract absorption of vitamin E (alpha-tocopherol) in horses were developed. Vitamin E was administered orally, and serum values of alpha-tocopherol were measured by use of high-performance liquid chromatography at 0, 3, 6, 9, 12, and 24 hours after vitamin E administration. Variables included comparison of 2 dosages (45 and 90 IU/kg of body weight), routes of administration, and absorption dynamics of 3 preparations of dl-alpha-tocopherol. Absorption of the 2 doses of dl-alpha-tocopherol acetate indicated a dose response; the area under the curve at 24 hours (AUC24) was 4.3 micrograms.h/ml for the 45-IU/kg dose and 32.2 micrograms.h/ml (P less than 0.01) for the 90-IU/kg dose. Maximal absorption was apparent when vitamin E was naturally consumed in grain, compared with administration of identical preparations by stomach tube or paste. In the same horses, dl-alpha-tocopherol and dl-alpha-tocopherol acetate plus polyethylene glycol had statistically similar absorption curves and both had significantly greater AUC24, compared with dl-alpha-tocopherol acetate; values for the 3 compounds were 23.6, 25.8, and 12.6 micrograms.h/ml, respectively. The AUC24 varied between individual horses, but time of peak value was consistently observed between 6 and 9 hours.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
9.
Five days after treatment with chlorpyrifos, a 1.5-year-old male llama was unable to stand, had saliva flowing from its mouth, and had constricted pupils, hyperglycemia, a metabolic acidosis, and a plasma pseudocholinesterase activity of 111 IU/L. Mean (+/- 1 SD) plasma pseudocholinesterase activity of 29 healthy llamas was 233.76 +/- 51.55 IU/L. Five to 8 days after topical application of chlorpyrifos (25 mg/kg of body weight) to 3 healthy llamas, the pseudocholinesterase activity decreased to 38% to 62% of pretreatment (base-line) activity and returned to within 90% of base-line activity by the 36th to 48th day after treatment.  相似文献   
10.
Blood samples were collected on nonracing days from 57 racing Greyhounds at 2 weeks, 8 weeks, 13 weeks, and 16 weeks after the beginning of the racing season. Hematologic and biochemical tests were performed to detect marked changes induced by stress of racing. In general, these Greyhounds were healthy. Rhabdomyolysis was detected in one dog. In several other dogs, possible subclinical muscle injury was identified by increased serum creatine kinase activities. Mean serum Ca concentrations tended to decrease during the racing season. None of the tests was a good predictor of racing performance. Mean values for several hematologic and biochemical tests were different from those of other breeds of dogs.  相似文献   
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