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101.
Comprehensive information on the role of β‐casein and plasminogen–plasmin (PG–PL) system in milk secretion of Murrah buffaloes during winter season is lacking, although effects of cold stress can be ameliorated to an extent by altering microclimate at farm level. Hence, this study was aimed to determine the changes in productivity along with PG–PL system of milk, plasma hormones and metabolites of buffaloes during winter (December–January) season under two different management systems. Average minimum temperature and wind chill index during this season were 7.02 and 12.74 °C respectively. Buffaloes were divided in two groups of six animals each: control and treatment, where treatment group animals were placed in‐house with floor bedding of paddy straw and the control group animals in loose housing system without straw bedding. Physiological responses were recorded, and milk and blood samples were collected at weekly intervals for six‐week experimental period. Under in‐house management system, buffaloes experienced better comfort by alleviating environmental stress as their physiological responses such as respiration rate and pulse rate were significantly reduced (p < 0.01) as compared to the control, which subsequently resulted higher milk yield by 9.92% (p < 0.05). Analysis of milk samples revealed higher concentration of plasminogen (10.6 vs. 8.05 μg/ml; p < 0.01) and β‐casein (p < 0.05), and lower plasmin level (0.299 vs. 0.321 μg/ml; p < 0.05) in buffaloes under treatment group. It was also found that plasma cortisol, glucose and non‐esterified fatty acids levels were higher (p < 0.01) in control group as compared to the treatment animals by 13.6%, 8.14% and 12.6% respectively. However, milk composition, growth hormone, epinephrine and norepinephrine level in plasma were similar in both the groups. Hence, it may be concluded that provision of in‐house shelter management with floor bedding of paddy straw during winter was effective to minimize environmental stress and improved milk production through manipulation of PG–PL system in buffaloes.  相似文献   
102.
  
  张明洁 《中国农学通报》2017,33(24):118-123
利用海南岛1990—2010年的芒果产量数据和1961—2010年的气象数据,计算了芒果的寒害减产历史序列,应用极值理论构建了产量风险分布模型,依此对各市(县)纯保险费率进行了厘定。并根据寒害的气象风险与产量风险区划成果,通过聚类分析得到区域风险系数,对纯保险费率进行修正,确定了不同免赔额下海南各市(县)芒果寒害保险的纯保险费率。结果表明:不同免赔额下白沙、琼中、五指山和澄迈的纯保险费率最高,说明其寒害风险最高,儋州、临高、屯昌的纯保险费率次之,风险也较高,这与气象指标统计的寒害风险基本一致,说明中部和西北部的芒果种植受寒害影响较大,适合采用高免赔额的费率标准。本研究中纯保险费率是根据气象资料计算而得的,避免了因采用产量资料出现资料短而不稳定的问题,可以有效的防止逆向选择和道德风险,有利于其他热带水果气象指数保险产品设计的借鉴,并使更多的农户参与到保险中来。  相似文献   
103.
黄土高原人工灌草系统不同立地条件土壤种子库特征   总被引:2,自引:0,他引:2  
本研究通过野外调查取样与室内试验相结合,连续两年对黄土高原人工灌草系统不同坡向、坡位进行取样,以期对该区土壤种子库的物种组成、密度特征及其物种多样性进行初步了解。研究结果表明:该人工灌草生态系统土壤种子库共有9科,15种,其组成因坡位、坡向以及年份而异;坡向、坡位均显著影响土壤种子库物种多样性指数、丰富度指数与土壤种子库密度(P<0.05),土壤种子库密度为3 218~5 492粒·m-2,总体呈现为阴坡显著高于阳坡(P<0.05),下坡位显著高于上坡位(P<0.05);坡位和坡向均对物种均匀性系数无显著影响;年份对土壤种子库无显著影响。上述研究可为黄土高原人工灌草系统的可持续利用与恢复提供参考依据。  相似文献   
104.
New Rice for Africa (NERICA) is a general name for interspecific rice varieties derived from a cross between the high‐yielding Asian rice (Oryza sativa L.) between locally adapted African rice (Oryza glaberrima Steud.). Eight NERICAs were evaluated for cold tolerance (CT) at the reproductive stage and compared with their O. sativa parents and three Japanese standard rice varieties over 3 years. Cold tolerance was evaluated based on the filled grain ratio (FGR) after cold water irrigation. The FGR was greatly reduced by cold water irrigation. NERICA 1, 2 and 7 had higher FGR (51.9–57.9 %), while NERICA 6, 15 and 16 had lower FGR (6.2–14.5 %). NERICA 1, 2 and 7 were less affected by cold stress, with a 31 % mean reduction in FGR, while NERICA 6, 15 and 16 were greatly affected, with their FGRs being reduced by more than 80 %. NERICA 3 and 4 were moderately affected by cold stress, with about 45 % reduction rate in FGR. FGR significantly influenced the grain weights of the varieties with strong positive correlations (r = 0.83–0.91; P < 0.001), and thus, similar trends in grain weights were observed. Grain weights were reduced by 61.7–96.4 % under cold stress. NERICA 1, 2 and 7 showed significantly better performance than NERICA 3 and 4, while NERICA 6, 15 and 16 performed poorly under cold water irrigation. The Japanese varieties Koshihikari (very tolerant) and Ozora (moderately tolerant) were more affected by cold water irrigation than NERICA 1, 2 and 7. On the basis of the mean reduction rate (%) in FGR under cold stress, the varieties were classified as follows: NERICA 1, 2 and 7 as tolerant; NERICA 3 and 4 as moderately tolerant; and NERICA 6, 15 and 16 as susceptible to cold stress. However, NERICA 7 grain yields were lower under cold stress due to both greatly reduced number of panicles per plant and number of spikelets per panicle. Therefore, NERICA 1 and 2 are suitable candidates for production in the highland regions of East Africa and should be promoted for production.  相似文献   
105.
In order to explore the effect of different L-lysine levels added in semen dilution on the fresh Dorper sheep quality stored at liquid state,3 health Dorper ram were used to collect semen which were equal-packaged and added to solution containing different levels (0,0.1,0.2,0.3,0.4 and 0.5 g) L-lysine in 120 mL diluent and at 0,6,24,30,48,54,72 and 78 h,the sperm motility,membrane integrity and acrosome integrity were detected.The results showed that the sperm motility in groups added 0,0.1 and 0.2 g L-lysine were higher than other groups,and that in 0.4 and 0.5 g L-lysine groups decreased faster than other groups;The sperm motility in 0.5 g L-lysine group reduced to 0 at 30 h,and it reduced to 0 at 48 h in the group added 0.4 g L-lysine;The effective survival time and survival index in the group added 0.1 g L-lysine was higher than other groups (P< 0.05);The membrane integrity of 0.1 g group was the highest,that had no significant difference with control group from 0 to 54 h (P >0.05),while after 72 h the two groups had significant differences (P< 0.05).The membrane integrity in 0.4 and 0.5 g groups were the worst,and that was significant different with other groups (P< 0.05);The acrosome integrity of 0.1 g group was the highest which had no significant difference with control group (P >0.05),0.4 and 0.5 g groups were the worst,the difference between them was not significant (P >0.05),while was extremely significant difference with other groups except for 0 and 6 h (P< 0.01).The results suggested that dilution added a high concentration of L-lysine could inhibit sperm quality,when the count of L-lysine was more than 0.2 g,sperm quality was significantly decreased,adding 0.1 g L-lysine could improve Dorper sheep fresh sperm quality stored at liquid state.  相似文献   
106.
2020年5月4日在江苏盐城大丰麋鹿国家级自然保护区(120°47′—120°53′E,32°59′—33°03′N)记录到3只彩鹮。栖息地为一处浅滩水塘,3只彩鹮于水中觅食。以往曾宣布彩鹮在国内绝迹,本次记录填补了彩鹮在本地区的分布空白,证实了彩鹮在江苏省仍有分布。这一纪录或许说明本地区栖息地得到了有效的改善。  相似文献   
107.
科栗1号是以S31-1为母本、S4-1为父本配制而成的南瓜一代杂种。植株蔓生,长势中等;分枝较少,叶小,节间短;第1雌花节位第9节左右;嫩瓜扁圆形,瓜皮绿色覆绿色斑点和浅色纵条斑纹,老瓜皮墨绿色。嫩瓜单瓜质量0.5~1.5kg,果实横径9cm左右,纵径13cm左右,糯性好,粉质,品质佳;春季露地和秋季设施栽培嫩瓜产量1500~2000kg·(667m2)-1,早春设施栽培嫩瓜产量3000kg·(667m2)-1左右。适宜浙江省及栽培条件相似的地区推广种植。  相似文献   
108.
AIM: To investigate the effect of paricalcitol (P) on renal tubulointerstitial fibrosis and the underlying mechanisms in diabetic nephropathy (DN).METHODS: DN rat model was induced by a single intraperitoneal injection of streptozotocin after fasting. The animals were randomly divided into 2 groups:the DN rats in paricalcitol-intervened group (group P) were injected intraperitoneally with paricalcitol dissolved in propylene glycol after the day when the model was induced successfully at a dose of 0.4 μg/kg (3 times a week); the DN rats in DN group (group D) were given isopyknic propylene glycol. Normal control group (group C) was also set up. The samples of blood, urine and renal tissue were collected after intervention of paricalcitol for 12 weeks. The biochemical indexes were measured. The renal tissues were used for pathologic observation and determining the expression of transforming growth factor-β1 (TGF-β1), Wnt-4, β-catenin and Klotho by immunohistochemistry and Western blotting. In addition, the correlation among the above indexes was analyzed.RESULTS: (1) Scr, BUN and 24 h urine protein increased significantly in group D compared with group C, while decreased in group P compared with group D (P<0.05). (2) The area of renal tubulointerstitial fibrosis increased in group D compared with group C, while decreased in group P compared with group D (P<0.05). (3) The expression of Klotho decreased, while the expression of TGF-β1, Wnt-4 and β-catenin increased in group D compared with group C (P<0.05). Compared with group D, the expression of Klotho increased, while the expression of TGF-β1, Wnt-4 and β-catenin decreased in group P (P<0.05). (4) The expression of Klotho was negatively correlated with the fibrosis area, TGF-β1, Wnt-4 and β-catenin (P<0.05).CONCLUSION: Paricalcitol inhibits renal tubulointerstitial fibrosis in DN by promoting the expression of renal Klotho, and inhibiting Wnt/β-catenin signaling pathway activation and TGF-β1 synthesis.  相似文献   
109.
[目的]明确野生兴安藜芦对榆紫叶甲不同龄期幼虫的防治作用.[方法]以野生兴安藜芦为材料,采用70%乙醇、60%丙酮、沸水对藜芦的根、茎、叶分别进行提取,研究各提取液对榆紫叶甲2龄、3龄、4龄幼虫的防治效果.[结果]兴安藜芦不同药用部位的杀虫活性具有明显差异,以根提取物的杀虫活性最强,叶提取物的杀虫效果最差;不同提取方法的杀虫效果也有明显不同,以70%乙醇提取液的杀虫活性最强.[结论]试验结果为榆紫叶甲的生物防治提供了参考.  相似文献   
110.
武玲萱  刘钊  王静 《中国蔬菜》2014,1(9):42-43
晋萝卜4 号是以雄性不育系4-01A 为母本,自交系03-37-1 为父本配制而成的秋冬萝卜一代杂种,生育期80 d(天)。地上部叶丛半直立,叶片稀疏,肉质根圆柱形,表皮光滑,出土部分皮绿色,入土部分皮白色,近1/2 露出地面。含水量适中,肉质甜脆,商品性好。肉质根纵径30 cm,横径7~8 cm,单根质量1.5 kg,每667 m2 产量5 000 kg 左右。适宜山西省及其周边地区种植。  相似文献   
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