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71.
研究啮齿动物的食性及其营养生态位特征不仅可以了解高寒草甸环境变化下物种的食性适应特征,还可探讨多种啮齿动物的种间关系。本研究采用粪便显微组织观察法,分析了甘南草原高原鼠兔(Ochotona curzoniae)、高原鼢鼠(Eospalax baileyi)和喜马拉雅旱獭(Marmota himalayana)3种啮齿动物的食性及营养生态位特征。结果发现:3种啮齿动物所采食的植物种类基本相同,但其比例各异;高原鼢鼠所采食的植物主要是珠芽蓼(Polygonum viviparum)和鹅绒委陵菜(Potentilla anserina)等杂类草,且对莎草科(Cyperaceae)植物的采食量显著高于其它两种动物,高原鼠兔主要采食禾本科(Poaceae)植物,喜马拉雅旱獭则主要采食禾本科和菊科(Asteraceae)植物;营养生态位宽度依次为喜马拉雅旱獭>高原鼢鼠>高原鼠兔,其中高原鼠兔与喜马拉雅旱獭的营养生态位重叠最大(0.52)。3种啮齿动物在食物上存在分化,营养生态位分离,是其共存的重要原因。  相似文献   
72.
采用二因素裂区设计,以保水剂和活性炭、硅藻土、凹凸棒为填充剂的包衣材料制作丸粒化胡麻种子,研究了丸粒化处理对胡麻种子萌发和幼苗生长的影响。结果表明:与不加保水剂相比,保水剂质量与种子质量为1∶1时,丸粒种子的活力指数和出苗率显著提高20.11%、18.62%;随着保水剂含量的增加,幼苗的根冠比显著减小3.25%。包衣剂中以活性炭:凹凸棒=1∶1为填充剂的发芽率和出苗率比不加填充剂的明显提高6.79%、22.41%,幼苗生长最健壮。与未丸粒化的种子相比,当保水剂质量与种子质量为1∶1时,以活性炭:凹凸棒=1∶1为填充剂的丸粒种子发芽指数、活力指数和出苗率显著提高,而且幼苗的茎粗、叶面积和根冠比分别显著增加11.02%、27.35%、28.07%。可见,适量的保水剂(保水剂质量与种子质量为1∶1)和以活性炭、凹凸棒为填充剂的包衣剂能提高胡麻种子活力,增加出苗率,使幼苗的干物质重增大,根系发达,根冠比提高,为胡麻高产奠定了良好的基础。  相似文献   
73.
本文分析了影响鸡肉品质风味的饲料因素,提出了在日粮中添加红枣富硒饲料、VE、益生菌、饲料添加剂等调控鸡肉品质风味的措施,以期为鸡养殖提供科学参考。  相似文献   
74.
75.
本试验旨在研究不同饲粮类型对育肥湖羊肌肉脂肪酸和氨基酸组成的影响。选用90只体重为(24.65±2.80)kg的90日龄健康公湖羊,随机分为3组,分别饲喂传统精粗饲粮+舔砖(CK组)、全混合饲粮(TMR组)、粗料+精料颗粒料(CP组),每组3个重复,每个重复10只羊。预试期10 d,正试期120 d。结果表明:饲粮类型对育肥湖羊血清和肝脏的总超氧化物歧化酶、谷胱甘肽过氧化物酶、过氧化氢酶活性和丙二醛含量以及总抗氧化能力均无显著影响;与CK组相比,TMR组育肥湖羊背最长肌中棕榈酸和总的饱和脂肪酸的比例分别降低了10.77%和9.18%(P<0.05),但CK与CP组差异不显著;TMR组油酸和总的单不饱和脂肪酸的比例较CK组分别升高了4.78%和4.71%(P<0.05),但CK与CP组差异不显著;与CK组相比,TMR组湖羊肌肉中异亮氨酸和必需氨基酸含量分别上升了10.34%和4.45%(P<0.05);TMR组非必需氨基酸和总氨基酸含量较CK组分别升高了2.33%和3.42%(P<0.05),但CK与CP组差异不显著。上述结果提示,与传统精粗饲粮相比,TMR可显著增加育肥湖羊肌肉中不饱和脂肪酸和必需氨基酸含量,降低饱和脂肪酸比例,改善肉品质,提升羊肉的营养食用价值。  相似文献   
76.
The objective of this study was to determine the effects of dietary levels of crude protein (CP) and levels of fermentable carbohydrates (FC) and their interaction on odour emission, odour intensity, odour hedonic tone, and ammonia emission from pig manure, and manure characteristics. An experiment was conducted with finishing pigs (n = 36) in a 2 × 3 factorial randomized complete block arrangement with 6 treatment combinations in 6 blocks. There were 2 dietary CP levels (low 12%; high 18%) and 3 digestible FC levels: (low 95.5; medium 145.5; and high 195.5 g/kg feed, as-fed basis). Pigs with an initial body weight (BW) of 57.7 ± 2.5 kg were penned individually in partly slatted floor pens. Faeces and urine of each pig accumulated in separate manure pits under the slatted floor. In the 6th week of the collection period air samples were collected directly above the manure in each pit. Manure samples were taken for manure characteristics. Air samples were analyzed for odour concentration and for hedonic tone and odour intensity. Manure samples were analyzed for volatile fatty acids (VFA), indoles, phenoles, sulphurous compounds, ammonium, and total N concentrations. Dietary CP level and FC level did not affect odour emission, odour intensity and hedonic tone but their interaction affected odour emission at P = 0.06. At a high dietary CP level, increased FC level decreased odour emission, while at a low CP level, increased FC level increased odour emission from pig manure. Total N and ammonium concentrations, and ammonia emission from pig manure were reduced at low dietary CP level (P < 0.001). High FC level led to low ammonia emission from pig manure (P = 0.01). Manure pH increased at high dietary CP level (P < 0.001) and decreased when FC level increased (P < 0.05). Total VFA concentration increased at high dietary CP level (P < 0.001) and when FC level increased (P < 0.001). Enhanced dietary CP increased the manure concentrations of phenol (P < 0.001), cresols (P = 0.01), indole (P < 0.001), 4-ethylphenol (P < 0.001) and carbon disulfide (P < 0.001), but FC did not affect concentrations of these compounds (P > 0.05) in the manure. We conclude that the interaction between dietary CP and FC plays a role in odour production and emission. Ammonia emission from pig manure can be reduced substantially by decreasing dietary CP and by increasing FC.  相似文献   
77.
There are many patterns of coexistence in communities, including partitioning based on spatial, temporal, or food niches. This study considered the partitioning of food between two ecologically similar and sympatric species, the tamarisk gerbil and the midday gerbil, in the Terek-Kuma Lowland of the Republic of Daghestan. The qualitative and quantitative characteristics of the diets of both gerbils were revealed. The species have relatively wide diets; the tamarisk gerbil’s diet consisted of forty-six plant species, and the midday gerbil’s diet consisted of fifty plant species within the study areas. Thirty plant species were present in the diets of the two gerbils. The dietary breadths of both gerbils were similar. The dietary overlap of the two gerbils ranged from low to moderate (average Pianka’s dietary overlap index, 0.476?±?0.08). Finally, under conditions in which food resources are sufficient, the moderate abundance of gerbils and the high diversity of habitats and microhabitats in the study areas allow these two species of gerbils to coexist in a common location.  相似文献   
78.
选用360头21日龄断奶仔猪,按制粒工艺、原料预处理不同设计2因素2水平试验,研究二次制粒颗粒饲料对断奶仔猪培育阶段生长性能的影响。结果:试验全期,采用二次制粒工艺及膨化玉米、膨化豆粕原料的处理组4,仔猪体重、平均日增重、饲料转化效率显著优于(P<0.05)其他3组。处理组4仔猪42日龄的血清尿素氮和皮质醇浓度显著低于其他3个处理组。试验表明,在选择膨化玉米与膨化豆粕优质饲料原料的基础上,采用二次制粒工艺,尤其先将鱼粉与膨化玉米、膨化豆粕进行第一次高温制粒,对降低应激、改善仔猪培育阶段的生长性能有良好的效果。  相似文献   
79.
80.
The goals of this study were to compare the efficacy of once-daily administered Glargine insulin to twice-daily administered Lente insulin in cats with diabetes mellitus and to describe the use of a high-protein, low-carbohydrate diet designed for the management of diabetes mellitus in cats. All cats with naturally occurring diabetes mellitus were eligible for inclusion. Baseline testing included a physical examination, serum biochemistry, urinalysis and urine culture, serum thyroxine concentration, and serum fructosamine concentration. All cats were fed the high-protein, low-carbohydrate diet exclusively. Cats were randomized to receive either 0.5 U/kg Lente insulin q12h or 0.5 U/kg Glargine insulin q24h. Re-evaluations were performed on all cats at weeks 1, 2, 4, 8, and 12, and included an assessment of clinical signs, physical examination, 16-hour blood glucose curve, and serum fructosamine concentrations. Thirteen cats completed the study (Lente, n = 7, Glargine, n = 6). There was significant improvement in serum fructosamine and glucose concentrations in all cats but there was no significant difference between the 2 insulin groups. Four of the 13 cats were in complete remission by the end of the study period (Lente, n = 3; Glargine, n = 1). The results of the study support the use of once-daily insulin Glargine or twice-daily Lente insulin in combination with a high-protein, low-carbohydrate diet for treatment of feline diabetes mellitus.  相似文献   
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