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1.
Our objective was to develop a lipopolysaccharide (LPS) inflammation model in calves to evaluate the acute-phase response with respect to the release of pro-inflammatory cytokines and acute-phase proteins, fever development and sickness behaviour. Fourteen 4-week-old male Holstein Friesian calves were included and randomly assigned to a negative control group (n = 3) and an LPS-challenged group (n = 11). The latter received an intravenous bolus injection of 0.5 μg of LPS/kg body weight. Blood collection and clinical scoring were performed at 0, 0.5, 1, 1.5, 2, 2.5, 3, 3.5, 4, 5, 6, 8, 12, 18, 24, 28, 32, 48, 54 and 72 h post LPS administration (p.a.). In the LPS group, the following clinical signs were observed successively: tachypnoea (on average 18 min p.a.), decubitus (29 min p.a.), general depression (1.75 h p.a.), fever (5 h p.a.) and tachycardia (5 h p.a.). Subsequent to the recovery from respiratory distress, general depression was prominent, which deteriorated when fever increased. One animal did not survive LPS administration, whereas the other animals recovered on average within 6.1 h p.a. Moreover, the challenge significantly increased plasma concentrations of tumour necrosis factor-α, interleukin 6, serum amyloid A and haptoglobin, with peaking levels at 1, 3.5, 24 and 18 h p.a., respectively. The present LPS model was practical and reproducible, caused obvious clinical signs related to endotoxemia and a marked change in the studied inflammatory mediators, making it a suitable model to study the immunomodulatory properties of drugs in future research.  相似文献   
2.
Fifteen, one year old swamp buffalo males with average liveweight of 200.5 ± 9.5 kg were randomly assigned according to a completely randomized design to receive three dietary treatments of supplemental vegetable oils in concentrate contained 140, 750, and 16 g of crude protein, total digestible nutrient, and ether extract, respectively (T1 = unsupplemented, T2 = supplemental coconut oil and sunflower oil in ratio 50:50 at 6% of concentrate, and T3 = supplemental sunflower oil at 6% of concentrate) during a 5-month feeding trial. Urea-treated rice straw was offered ad libitum and concentrate was supplemented at 150 g/kg BW. The results revealed that supplementation of vegetable oils decreased dry matter intake in sunflower oil supplemented group. Combination of coconut oil and sunflower oil supplementation resulted in similar average daily gain as those found in control and in sunflower oil supplemented groups. Rumen microorganism population, ammonia–nitrogen, blood urea–nitrogen and total volatile fatty acid concentrations were decreased as vegetable oils were supplemented. Oil supplementation slightly reduced growth rate, hot carcass percentage, loin eye area particularly on sunflower oil supplemented group. Based on these findings, vegetable oil resulted in decreased performance of swamp buffaloes although the combination of coconut oil and sunflower oil could reduce negative effect of unsaturated oil supplementation. However, further analyses of conjugated fatty acids (CLA) in meat could offer useful information in determining pronounced effects of vegetable oil supplementation.  相似文献   
3.
He-Ne激光辐照野桑蚕蛹的子代,获得长茧丝(SC)和斑纹变异(BW)个体,经继代饲养,对其发育、形态性状、茧质和丝质进行调查、统计和F测验,SC区的丝长和纤度与对照区差异达到显著和极显著程度,而BW区表现为变异谱扩大,产生变异油蚕。因此He-Ne激光对野桑蚕具有遗传诱变效应,诱变出长茧丝、细纤度特殊经济性状的个体,在育种上有实用意义。  相似文献   
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5.
芝麻轻简栽培技术试验初报   总被引:4,自引:0,他引:4  
通过对芝麻免耕撒播、免耕条播的3种密度试验表明:免耕撒播种植密度为18万株/hm2时能获得较高产量,且高于对照,但差异不显著;纯收入达9912.5元/hm2,较对照增收54.58%。因此,免耕撒播具有轻便、省工、增产、增效的优点。  相似文献   
6.
竹木复合中密度纤维板工艺条件的研究   总被引:11,自引:2,他引:9  
研究了竹木纤维混合比、空比和纤维筛分值工艺条件对木复合中密度性能的影响。结果表明,在合适的工艺条件下,可以生产出具有优良性能的竹木复合中密度纤维板。竹木复合中密度纤维板的静曲强度、弹性模量和吸水厚度膨胀率随竹木纤维混合比的增大而增大;而平面抗拉强度在0/1~1/1范围内随竹木纤维混合比加大模量和吸水厚度膨胀率随竹木纤维混合比为1/1时,IB最小。板的静曲强度、弹性模量、平面抗拉强度和吸水厚度膨胀率  相似文献   
7.
随机实测261头黎平黄牛的胸围,体斜长和体重,根据体重等于体积乘以密度的原理,采用回归分析方法进行了黎平黄牛体重估测公式的推导与验证。结果表明,黎平黄牛的性别对体尺与体重回归关系的影响差异不显著,合并公母牛的体尺体重数据。得出该品种总的体重估测公式:体重=胸围^m)*体斜长(m)*88-8(r=0.9971,Sy/x=4.701)。胸围,体斜长对体重的回归关系极显著。估测体重的离回归标准误为4.7  相似文献   
8.
Fifty-two multiparous Brahman type cows with reproductive tract scoring (RTS) ≥4 at 45 days post-partum were randomly assigned to two groups of 26 cows each separated into an ad libitum suckling group (C) and treatment group (T). Calves in the T group were separated for 12 h during the night from 45 days post-partum to the onset of the breeding season. Body condition score (BCS) and body weight (BW) were recorded 45 days post-partum, at the start of the breeding season, and at pregnancy diagnosis. Calves were weighed at calving and weaning. Weaning weights were corrected to 205 days. BW and BCS at the onset of the breeding season were similar (p > 0.05) between the experimental groups. Calving to breeding intervals were 93 ± 18 d and 99 ± 22 d for T and C groups, respectively. Calving to conception intervals differed significantly between the groups (111 ± 10 d for T and 133 ± 19 d for C) and a similar result was obtained for the breeding to conception intervals (18 ± 15 d for T and 31 ± 19 d for C). Conception rates were 80% for the T group and 59% for the C group, which correlated better with BW than BCS at the onset of the breeding season. Weaning weights differed (p < 0.05) between C and T groups. From 45 days post-partum to the onset of the breeding season, cows in the T group experienced a positive energy balance (3%) while those in the C group had a negative energy balance (-0.1%). It was concluded that 12 h calf separation at night increases the conception rates and improves the calf weaning weights of Bos indicus beef cattle under extensive production systems in sub-tropical conditions.  相似文献   
9.
黎平黄牛体重估测公式探讨   总被引:3,自引:0,他引:3  
随机实测261头黎平黄牛的胸围,体斜长和体重,根据体重等于体积乘以密度(比重)的原则,采用回则分析方法进行了黎平黄牛体重估测公式的推导与验证。结果表明,黎平黄牛的性别对体尺与体重回归关系的影响差异不显著(P〉0.05),合并公母牛的体尺体重数据。得出该品种总的体重估测公式;体重(kg)=胸围^2(m)×体斜长(m)×88-8(r=0.9971,Sy/x=4.701)胸围,体斜长对体重的回归关系极显  相似文献   
10.
Even though the bacterial wilt is identified as the most destructive disease in hot peppers world-wide, robust molecular markers that facilitate marker assisted selection are absent till date. Kerala Agricultural University (India) has released two hot peppers named Ujwala and Anugraha which show high level field resistance to this pathogen. The variety Anugraha was developed through backcross breeding between a high yielding but highly susceptible variety Pusa Jwala with the highly resistant Ujwala, using Pusa Jwala as a recurrent parent. Thus, Pusa Jwala and Anugraha are near isogenic lines (NILs) differing for the resistance to bacterial wilt only and the resistance is governed by a homozygous recessive (rr) gene action. The F1s of Anugraha × Pusa Jwala were selfed to generate the segregating F2 population. The F2 population has been field screened, 10 highly susceptible and 10 most resistant plants were identified and DNA from these plants were bulked separately. Bulked segregant analysis with AFLP primer combination EcoACT + MseCAC was done using the DNA from donor parent Ujwala, susceptible parent Pusa Jwala, resistant parent Anugraha, bulked susceptible F2 and bulked resistant F2 plants. On resolution using capillary electrophoresis system in genetic analyzer, the AFLP products have yielded three polymorphic bands (103, 117, and 161 bp) which were linked with the resistant recessive allele and three polymorphic bands (183, 296, 319 bp) linked with the dominant susceptible allele of the bacterial wilt resistance gene. The results were confirmed through co-segregation analysis in most resistant and susceptible plants of F2 segregating population.  相似文献   
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