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Reena Kamal Triveni Dutt Manjunath Patel Amitava Dey Panch Kishore Bharti Poolangulam Chinnakkan Chandran 《Tropical animal health and production》2018,50(4):701-706
In tropical countries, at high temperatures, several physiological rearrangements occur in cows as they attempt to facilitate heat dissipation and/or reduce metabolic heat production. Following exposure to heat, cattle appear to acclimatize within 2–7 weeks. The failure of homeostasis at high temperatures may lead to reduced productivity or even death. The situation is even worse when humidity adds to high temperature. Livestock with elevated body temperature exhibit lower DMI and growth with less efficiency, reducing profitability for dairy farms in hot and humid climates. Shading of feed and water also offers production advantages. Although several elaborate methods for reducing heat stress in cows have been reported, simple shade materials appear to be the most cost-effective methods that are currently applicable to tropical developing countries. Different materials are being used to provide shade during warm weather. The shade material determines the microclimate—it should be light, strong, durable, weatherproof, good looking and a bad conductor of heat, and free from tendency to condense moisture inside. This review discusses various shade materials and their advantages and disadvantages in different situations. 相似文献
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伤口愈合是一种复杂的现象,是机体控制的系统对细胞进行精微同步调节的结果.然而,一系列可变因素通过多种方法来影响此过程.通常来说,机体内的各种维生素,矿物质,脂肪酸,氨基酸和其他营养物质对该过程起着直接或间接的重要影响.不仅如此,各种疾病与无数的外界因素也以不可预料的形式影响着该过程.因此,任何治疗方法都是努力控制上述因素以使机体处于最佳恢复状态.因此,当这种天然愈合过程被打断,机体的伤口就会转变为慢性,或者出现溃疡. 相似文献
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Mastomys natalensis pretreated with diethylcarbamazine (DEC), levamisole or centperazine were exposed to the standard inoculum of infective larvae of Brugia malayi. Percentage 'take' of infection, duration of prepatent period, course of microfilaraemia and number of adult worms recovered were compared with those of untreated infected Mastomys (control). DEC and centperazine did not alter the 'take' (DEC/centperazine: 100%; control: 88.24%) and the average prepatent period (DEC: 105.44 days; centperazine: 105.18 days, control: 109.20 days). In levamisole pretreated animals on the other hand, the 'take' was much lower (68.18%) with extended prepatent period (125.87 days). However, unlike centperazine and control, the course of microfilaraemia was identical in DEC and levamisole pretreated animals. The average adult worm recovery was significantly high in centperazine pretreated animals being 14.09 as against 8.12, 7.46 and 8.42 in DEC, levamisole pretreated and control animals, respectively. 相似文献
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The photochemical degradation of the herbicide isoproturon in aqueous and non-aqueous solutions and in soils has been investigated. Four new photometabolites were formed in non-aqueous solution and three in soil. These were characterised by spectroscopic methods and identified by comparison with authentic synthetic samples such as 3-(4-isopropylphenyl)-1-methylurea; 3-(4-isopropylphenyl)urea; 4,4′-diisopropylazobenzene and 4,4′-diisopropylazoxybenzene. The pathway of formation of these photo products is depicted. 相似文献
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The chemotherapeutic efficacy of mebendazole given in combination with Freund's complete adjuvant (FCA) against Brugia malayi in multimammate rat was evaluated. Animals treated with mebendazole, orally at 200 mg/kg x 5 consecutive days along with FCA given subcutaneously (s.c.) on day -10, day 0 and day +15 of the drug treatment killed 48.51% of the adult worms. This drug given alone at the same regimen and by the same route showed only 18.7% mortality rate on adults. Mebendazole given intraperitoneally along with FCA given s.c., however, was four times more efficacious as filaricide than mebendazole alone. Nevertheless, the animals receiving FCA alone also revealed 23.5% mortality rate of adult worms. The animals receiving a combination therapy or FCA alone showed significant increase in antibody titre to the filariae which however decreased in the later stages. No enhancement of antibody level could be detected in animals treated with mebendazole alone. The non-specific immunopotentiation induced by FCA appeared to play a major role in enhancing the activity of mebendazole. 相似文献
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Total phenolic content in eight diverse wheat lines showed that PF-70354 YACO'S' had the highest (802.90 ± 1.35 μg g−1 fresh weight) and Agra Local possessed the lowest amount (684.72 ± 5.28 μg g−1 fresh weight). However, for further experiments two lines namely, ACC-8226 and MP-845, with contrasting disease scores under field trials were assessed. Pre-infectional levels of total phenolics and peroxidase activity were higher in ACC-8226 than in MP-845. Furthermore, the amount of phenolics and peroxidase activity in each case increased after inoculation. The post-infectional levels of phenolics and peroxidase were again higher in ACC-8226 than in MP-845. The peroxidase activity decreased with age in both the varieties, with very little peroxidase activity after 35th day. However, the amount of phenolics started to decrease with the progress of disease and age in MP-845, whereas in ACC-8226 an elevated level of it was maintained. Our findings not only support that ACC-8226 is the resistant and MP-845 is the susceptible variety but also provide important biochemical parameters for plant breeders to authentically identify potential breeding material and plan effective breeding strategies using these tools. 相似文献