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41.
Salt cedar (Tamarix spp.) readily invades and dominates riparian areas and lake basins throughout the western United States. Traditional control efforts (chemical and mechanical control) are expensive and provide limited long-term control. The salt cedar leaf beetle (Diorhabda elongata) provides a method of biological control through reduction in cover. However, population establishment of leaf beetles in some locations is often difficult because of environmental conditions. In previous research, goats readily consumed salt cedar, offering an alternative method of reducing salt cedar cover. For this study, we determined if sheep would consume salt cedar and consume a similar amount as goats. Twelve Rambouillet and 12 Suffolks lambs were fed salt cedar once daily (Trial 1) and three times daily (Trial 2). Intake of salt cedar by sheep was compared between breeds and with intake of salt cedar by goats (n = 10). Salt cedar was fed once a day in Trial 1 for 30 min over 15 d. Intake was recorded daily for individual animals. In Trial 2, salt cedar was offered three times daily for 13 d with intake recorded. There were no differences (P > 0.05) between breeds of sheep. In addition, sheep consumed more salt cedar than goats except on the last day of the study. When salt cedar was offered three times daily, both breeds of sheep increased intake and gained weight over the 13 d of feeding in Trial 2. By the end of the study, intake appeared to still be increasing. Collectively, these results illustrate that both Rambouillet and Suffolk sheep will consume a similar amount of salt cedar as goats and will provide another species of livestock that can be potentially used to reduce salt cedar cover. 相似文献
42.
法系獭兔血液中AKP活性与体尺、体重性状的关系 总被引:1,自引:0,他引:1
对20只40日龄法系獭兔和20只68日龄法系獭兔(公、母各半)血液中AKP活性进行了测定,并分析了40日龄与68日龄法系獭兔血液中AKP活性与体重、体长、胸围的相关性。结果表明:40日龄时法系獭兔血液中AKP活性高于68日龄;日龄相同时,公兔活性显著高于母兔(P<0.05);40日龄AKP活性与体重有较为密切的关系,其他相关则不显著。 相似文献
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The objective was to evaluate the effects of gymnastic training on stride characteristics of walk and trot in therapy horses carrying riders of different weights. Eighteen horses used for therapeutic riding 5 days/week were randomly divided into 2 groups. Nine horses performed gymnastic (GYM) exercises after therapeutic riding on 4 days/week for 3 months, 9 horses did no additional exercises (SED). On days 0 and 90, an inertial sensor mounted to the girth on the ventral midline was used to evaluate stride characteristics when horses were ridden at walk (1.3 m/second) and trot (3.0 m/second) by able-bodied riders representing rider: horse body weight ratios (BWRs) 15%, 20%, and 25%. On day 0, the measured variables did not differ significantly between sedentary (SED) and GYM groups, but on day 90, the following statistically significant results were found: GYM-trained horses had higher regularity for all BWRs at walk and 15% and 20% BWRs at trot. Higher stride symmetry was found in GYM-trained horses carrying 25% BWRs at walk and all rider weights at trot. Dorsoventral displacement was higher in GYM-trained horses when carrying 20% and 25% BWRs at walk and 25% BWRs at trot. Dorsoventral power was lower in SED-trained versus GYM-trained horses carrying 15% BWR at walk and 20% BWR at trot. A more regular and symmetrical stride with a larger range of dorsoventral trunk motion is likely to provide a better therapeutic riding experience. 相似文献
45.
研究了兰州市2006~2013年土地生态安全的时空差异。主要依据PSR模型建立评价指标体系,运用熵权法与综合评价法对不同时期兰州市及各县区土地生态安全状况进行分析。结果表明:(1)兰州市土地生态安全由2006年的"恶劣"状态转变为2013年的"良好"状态;(2)土地生态压力指数从0.176下降为0.145,土地生态状态与土地生态响应指数分别从0.063、0.160提升到0.295、0.290;(3)区域内空间分布差异较为明显,土地生态状态改善与响应增强主要集中在土地生态压力过大的地方。据此可知,兰州市土地生态结构和功能基本完善,已步入良好阶段,但是各县区土地生态空间分布差异较大。 相似文献
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飞鸭体尺与屠宰性能测定及其相关性分析 总被引:1,自引:0,他引:1
试验测定了8周龄天农飞鸭的体尺与屠宰性能,分析了各指标间的相关性。结果表明,半潜水长、胫长和宰前体重在公母鸭之间存在极显著差异(P<0.01),体斜长、龙骨长和胫围在公母鸭之间存在显著差异(P<0.05);屠体重、半净膛重、全净膛重、腿肌重在公母鸭之间存在极显著差异(P<0.01),瘦肉重在公母鸭之间存在显著差异(P<0.05)。宰前体重与体尺各指标(胸宽除外)间存在着极显著相关(P<0.01);试验所测的9个体尺指标均与宰前体重、屠体重、半净膛重、全净膛重之间存在显著(P<0.05)或极显著(P<0.01)正相关;宰前体重、屠体重、半净膛重、全净膛重、胸肌重、腿肌重和瘦肉重相互之间呈强相关(P<0.01),但体重和屠体重却与以上其它重量性状的百分率指标间无明显相关(P>0.05)。 相似文献
48.
本研究旨在探讨兰州大尾羊×小尾寒羊F1代羔羊体重和体尺的相关关系,为通过体尺性状估计其体重提供科学的理论依据。试验随机选取80只150日龄兰小杂交F1代羔羊,公、母羔各半,测量其体重(Y)、体长(X1)、体高(X2)、胸围(X3)、管围(X4)、胸深(X5)和胸宽(X6),运用SPSS 22.0软件分别对公、母羔的体重和体尺数据进行相关性分析、通径分析、逐步线性回归分析和相关系数的分解。结果表明,兰小杂交F1代羔羊的体重与体长、体高、胸围、管围、胸深、胸宽均呈极显著正相关(P<0.01),公、母羔胸围与体重的相关程度最高,相关系数分别为0.907和0.908,其次为体长,相关系数分别为0.875、0.844。各体尺性状间也呈极显著正相关(P<0.01),其中胸围和体长的相关系数最高。胸围和体长主要通过直接作用影响体重,胸深、管围、体高、胸宽主要通过间接作用影响体重,胸围对体重的直接作用最大,胸深对体重的间接作用最大。公、母羔体重与体尺的最优回归方程分别为:Y=-43.861+0.675X3+0.394X1(r=0.945,P<0.01)和Y=-38.378+0.590X3+0.397X1(r=0.948,P<0.01)。综上所述,胸围和体长是影响兰小杂交F1代羔羊体重的两个重要因素,在该品种的选育和肥羔的生产过程中,要加强对胸围和体长的选择力度,同时考虑胸深、管围、体高、胸宽的影响。 相似文献
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Melinda Poole Jessica M. Quimby Tianhua Hu Daizie Labelle William Buhles 《Journal of veterinary pharmacology and therapeutics》2019,42(2):179-188
Mirtazapine is classified as a weight gain drug in cats, and the purpose of this study was to evaluate its efficacy in cats experiencing unintended weight loss. This was a multi‐center, double‐blind, placebo‐controlled, randomized clinical study in client‐owned cats ≥1 year of age, weighing ≥2 kg, with a documented loss (≥5%) in body weight. Cats were treated once daily with either 2 mg/cat mirtazapine transdermal ointment (n = 83) or placebo (n = 94) (Per Protocol population) applied to the inner surface of the pinna for 14 ± 3 days. Physical examination, body weight, complete blood count, serum chemistry, and urinalysis were performed prior to treatment and on Day 14. Changes in body weight between the mirtazapine and placebo groups were evaluated from Day 1 to Day 14 and compared using a two‐sample t test. The mean percent change in body weight was +3.9% (standard deviation ±5.4%) in the mirtazapine group and +0.4% (±3.3%) in the placebo group (p < 0.0001). The most common adverse event was mild erythema at the application site in 17.4% of placebo and 10.4% of mirtazapine‐treated cats. Application of mirtazapine transdermal ointment was well tolerated both topically and systemically and resulted in significant weight gain in cats experiencing unintended weight loss associated with various underlying diseases. 相似文献