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101.
 论文对柴达木地区山羊养殖品种、基本情况、存在问题和发展思路做一综述,仅供同行参考与借鉴。  相似文献   
102.
《家畜环境卫生学》教学模式的探索   总被引:1,自引:1,他引:0       下载免费PDF全文
 《家畜环境卫生学》是动物科学和动物医学专业的专业基础课,是一门理论和实践应用紧密结合的课程。结合对动物科学、动物医学专业教学改革实际,论文从教学方法和手段、实验课程教学以及教学实习基地建设等方面进行论述,探索家畜环境卫生学理论与实践教学模式,提升教学效果。  相似文献   
103.
放牧条件下绒山羊绒毛季节性生长变化规律的研究   总被引:11,自引:0,他引:11  
本试验研究放牧条件下绒山羊绒毛季节性生长变化的规律。选择体重及产绒性能相近的2.5岁内蒙古白绒山羊羯羊10只,随机均分为2组,分别接受自然光照和短光照处理,短光照组每天的光照时间比自然光照组减少2小时,两组试羊在同一草场放牧。结果表明,放牧条件下,随牧草营养值下降(CP含量13.9%~6.0%)和光照递减(14.6~9.4h/d),绒毛生长呈慢—快—慢增长模式,主要的生长期在9月下旬~12月上旬,11月份为高峰期;减少光照可刺激绒毛生长,使快速生长的时间提前至8月下旬,绒毛长度增加10.9%,但生长模式不变。绒毛细度(14.6~14.9μm)和强度(6.9~5.9g)不受季节影响,但绒毛伸度下降54.3%;减少光照不改变绒毛强度和伸度,但绒毛细度增加5.6%、产绒量提高12.5%。  相似文献   
104.
高原山羊血气分析   总被引:1,自引:1,他引:1  
有血气分析仪对21只高原山羊进行血气分析,结果:pH7.35±0.05,PCO24.74±0.42kPa,PO23.79±1.05kPa,HCO-320.08±3.03mmol/L,TCO221.9±3.07mmol/L,BE-4.98±2.31mmol/L,SBC 20.25±2.65mmol/L,SBE-6.19±2.86mmol/L,O2S%49.47±14.8。表明血气值在不同性别、不同年龄间无显著差异(P>0.05)。  相似文献   
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Urolith formation has been documented in giraffes and goats. As research in giraffes poses logistical challenges, 16 buck goats were used as a model. The impact of two commercially available, pelleted feeds used for giraffes, ADF‐16 and Wild Herbivore (WH), as well as the impact of alfalfa hay and pellet proportions (20% hay:80% pellets, 80P or 80% hay:20% pellet, 20P) on the formation of urolithogenic precursors in goat urine was accomplished in a 2 × 2 factorial balance study. Complete diets contained 0.60, 0.32, 0.35 and 0.26% phosphorus (P) with calcium:P ratios of 1.60, 4.16, 3.06 and 5.23, for 80P‐ADF‐16, 20P‐ADF‐16, 80P‐WH and 20P‐WH respectively. Total faeces and urine were collected over two 5‐day periods to assess N and mineral balance. Fresh urine samples were collected and evaluated microscopically for urolithic crystal content. Urinary nitrogen (N) was lower and N retention was higher in goats fed 80P diets (p < 0.05). Intake of P was greatest for goats fed 80P‐ADF‐16; however, urinary P excretion and P retention were not affected by treatment. Crystal scores were higher in animals receiving 80P diets (p = 0.08), with crystals being composed predominantly of calcium phosphate. Urine pH was alkaline (>8) for all treatments. Urinary P concentration, a risk factor for urolithiasis, was highest (p 0.06) in the 80P‐ADF‐16 treatment (0.38 vs. 0.01, 0.02 and 0.04 mg/dl for 20P‐ADF‐16, 80P‐WH and 20P‐WH respectively), reflecting its highest dietary P level. Further investigation is recommended to determine the long‐term effects of these diets on urolithogenic compound formation.  相似文献   
109.
复合人工湿地对新农村生活污水的净化效果   总被引:2,自引:0,他引:2  
[目的]研究复合人工湿地对新农村生活污水的净化效果。[方法]通过建设复合垂直流-水平潜流人工湿地系统,研究其对接收新农村生活污水及雨污的池塘废水的净化效果。[结果]在春、夏、秋三季,复合人工湿地系统对废水均有较好的去除效果,且去除效果稳定。在整个运行期内,复合人工湿地系统对CODCr、TP、TN、NH4+-N的平均去除率分别达到64.71%、64.81%、40.21%、54.26%以上,且出水平均浓度均达到《地表水环境质量标准》(GB3838-2002)III类水质标准。复合人工湿地系统的二级湿地单元出水水质明显优于一级湿地单元,但第一级的处理效果高于第二级。[结论]该研究可为新农村生活污水治理提供参考依据。  相似文献   
110.
Forty-eight male Lezhi black goat kids with similar body weight ((12.09±1.70) kg) and age ((60±5) d) were used to determine the effect of dietary copper (Cu), in the form of reagent grade Cu sulfate (CuSO45H2O), on performance, serum lipid profile, and the relative mRNA abundance of genes involved in lipid metabolism.  Goat kids were stratified by body weight and randomly assigned to one of 4 treatment groups.  Each treatment consisted of 12 replicate pens with each pen containing one goat kid.  Treatment groups received the basal diet with no supplemental Cu (control), basal diet plus 10 mg of Cu kg–1 of dry matter (DM), basal diet plus 20 mg of Cu kg–1 of DM, or basal diet plus 30 mg of Cu kg–1 of DM.  Goats were housed individually in pens and fed a high-concentrate pelleted diet for 60 d.  Average daily gain, average daily feed intake and feed:gain of goats were not affected by dietary Cu supplementation (P>0.10).  No differences were detected in serum total cholesterol, triglyceride, and high density lipoprotein cholesterol concentrations of goat kids fed with different Cu concentrations (P>0.05).  However, serum low density lipoprotein cholesterol concentrations decreased linearly (P=0.01) as the concentration of dietary Cu increased.  Intramuscular fat content of longissimus muscle increased (P=0.002) quadratically and liver Cu concentrations increased (P<0.001) linearly as dietary Cu concentration increased.  Compared with the control, dietary supplementation of 20 mg Cu kg–1 DM decreased the relative mRNA abundance of fatty acid-binding protein 4 (P=0.01) and lipoprotein lipase (P=0.05), and tended to decrease the relative mRNA abundance of carnitine palmitoyltransferase I (P=0.06) in longissimus muscle of goats.  The relative mRNA abundance of peroxisome proliferator-activated receptor alpha (P<0.001), carnitine acetyltransferase (P=0.001), and carnitine palmitoyltransferase I (P=0.001) were also decreased in liver by Cu supplementation.  These results indicate that dietary supplementation of Cu modified lipid metabolism by increasing muscular fat and decreasing serum low density lipoprotein cholesterol, and the modification might be associated with the reduction of relative mRNA abundance of genes for oxidation of long-chain fatty acid in muscle and liver of Lezhi black goat kids.  相似文献   
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