三分域模型在研究单胃动物内源氨基酸排泄中的应用   总被引：1，自引：0，他引：1  

陈正玲  明道绪 《动物营养学报》2001,13(2):5-9

本文在分析三分域链状系统模型及单胃动物内源氨基酸排泄特点的基础上 ,讨论了如何将三分域链状模型用于单胃动物内源氨基酸排泄模式的确定。研究分三步进行 :1.测定动物血液体积 ;2.静脉连续灌注同位素标记的氨基酸并使之于体内达到平衡 ;3.检测消化道中同位素标记氨基酸的排泄率。文章指出 ,若能对所有必需氨基酸的内源排泄率均进行测定 ,则可得出内源氨基酸排泄模式 ,因而在实际测定饲料或日粮真可消化氨基酸含量时 ,只需测定某种氨基酸的内源排泄量即可知其它氨基酸的内源排泄状况  相似文献   

Estimation of daily and total lactation milk yield of Chios ewes from single morning or evening records     

Z. Basdagianni  G. Banos  Z. Abas  G.E. Valergakis 《Livestock Production Science》2005,92(1):59-68

Linear models were developed and evaluated for the estimation of daily (24 h) and total lactation milk yield of dairy sheep from single morning (am) or evening (pm) milking records. A total of 22,908 individual test-day milk records of 5110 ewes of the Chios breed, raised in 46 flocks, were used. Depending on the model, different daily milk yield estimates were derived for each ewe, accounting for lactation number, stage of lactation, season of previous lambing and interval between successive milkings. Daily milk yield was also estimated from doubling the single am or pm record. Actual and estimated yields were compared using root mean square errors (RMSEs), mean absolute differences, an accuracy parameter defined as the ratio of the actual yield variance over the sum of the variances of actual yield and absolute difference, and the product moment correlation between estimated and actual yield. Results were validated on independent datasets. Linear models resulted in less biased and more accurate estimates of the daily milk yield than simply doubling the am or pm record. Root mean square errors decreased by 7-37% and the mean absolute difference was reduced by 1-4% of the average daily yield. Higher accuracy and correlation were obtained from linear model application than doubling. Total lactation milk yield was predicted based on actual daily yield and compared to predictions based on estimated daily yield from am or pm records, as well as directly on single milking records. Root mean square errors obtained when daily yield had been estimated with linear models were 26-35% lower compared to doubling the am or pm yield and 0-13% lower compared to estimating the total lactation yield directly from single milking records. Linear model application also resulted in lower mean absolute difference and higher accuracy and correlation than doubling the am or pm record. Recording the yield of a single milking (am or pm) instead of both can benefit milk recording by reducing its cost and increasing farmer participation. In this context, linear models developed in the present study can be used for the accurate estimation of daily (24 h) and total lactation milk yield from single milking records.  相似文献   

国产克洛素隆尿药排泄数据分析     

胡振英  史彦斌  张新国  罗永江  罗超应  尚若峰  梁纪兰  崔颖  郑继方 《中兽医医药杂志》2004,23(4):9-11

应用Kromasil-C18色谱柱(250 mm×4.6 mm,5 μm),WatersTM480型可调波长紫外检测器,0.01M磷酸钾(pH=7):乙腈(3:1)为流动相,检测波长265 nm,含量测定采用标准曲线法,建立了RP-HPLC法检测绵羊尿中克洛素隆含量的方法.方法有效性评价结果表明,尿药含量在0.01～5.0μg/ml及5.0～30.0μg/ml范围呈良好线形关系(r=0.9993、0.9995),方法平均回收率99.32%,日内、日间变异系数分别为3.91%、6.28%.尿药最低检测限0.005μg/ml.试验绵羊以7 mg/kg单剂量经静脉、肌肉及口服三种途径给药后,尿中药物浓度分析表明,克洛素隆经体内处理后主要经肾脏排泄,给药96 h内,静注经尿排泄原药为81.76%,肌注为64.03%,口服为48.50%.  相似文献   

蚕粪中提取叶绿素铜钠盐的稳定性研究   总被引：10，自引：3，他引：10  

胡军华  张袁松  李鸿筠  姚廷山  刘浩强  雷慧德  陆红霞 《蚕业科学》2005,31(3):370-373

以蚕粪为原料,95%的乙醇为溶剂提取叶绿素,并通过化学法制得叶绿素的铜纳盐。采用721分光光度计对叶绿素铜钠盐进行定性、定量测定,确定该色素测定系统中的最大波长为414nm。通过测量吸光值研究了几种常用食品添加剂对叶绿素铜钠盐稳定性的影响,并对其耐光、耐热、耐酸碱及耐氧化性、耐还原性进行探讨。结果表明:叶绿素铜钠盐在70℃以下稳定性较好;光照对叶绿素铜钠盐稳定性的影响较大;还原剂(Na2S2O3)对叶绿素铜钠盐稳定性的影响较大,氧化剂在短时间内对其稳定性的影响不大,但放置的时间不宜超过30min;叶绿素铜钠盐在pH值为6以上的溶液中较为稳定,且有机酸及单糖对其稳定性无明显影响。  相似文献   

Pharmacokinetic assessment of the monepantel plus oxfendazole combined administration in dairy cows          下载免费PDF全文

M. Ballent  P. Viviani  F. Imperiale  P. Dominguez  S. Halwachs  H. Mahnke  W. Honscha  C. Lanusse  G. Virkel  A. Lifschitz 《Journal of veterinary pharmacology and therapeutics》2018,41(2):292-300

Monepantel (MNP) is a novel anthelmintic compound launched into the veterinary pharmaceutical market. MNP is not licenced for use in dairy animals due to the prolonged elimination of its metabolite monepantel sulphone (MNPSO₂) into milk. The goal of this study was to evaluate the presence of potential in vivo drug‐drug interactions affecting the pattern of milk excretion after the coadministration of the anthelmintics MNP and oxfendazole (OFZ) to lactating dairy cows. The concentrations of both parent drugs and their metabolites were measured in plasma and milk samples by HPLC. MNPSO₂ was the main metabolite recovered from plasma and milk after oral administration of MNP. A high distribution of MNPSO₂ into milk was observed. The milk‐to‐plasma ratio (M/P ratio) for this metabolite was equal to 6.75. Conversely, the M/P ratio of OFZ was 1.26. Plasma concentration profiles of MNP and MNPSO₂ were not modified in the presence of OFZ. The pattern of MNPSO₂ excretion into milk was also unchanged in animals receiving MNP plus OFZ. The percentage of the total administered dose recovered from milk was 0.09 ± 0.04% (MNP) and 2.79 ± 1.54% (MNPSO₂) after the administration of MNP alone and 0.06 ± 0.04% (MNP) and 2.34 ± 1.38% (MNPSO₂) after the combined treatment. The presence of MNP did not alter the plasma and milk disposition kinetics of OFZ. The concentrations of the metabolite fenbendazole sulphone tended to be slightly higher in the coadministered group. Although from a pharmacodynamic point of view the coadministration of MNP and OFZ may be a useful tool, the presence of OFZ did not modify the in vivo pharmacokinetic behaviour of MNP and therefore did not result in reduced milk concentrations of MNPSO₂.  相似文献   

Effects of the sodium‐glucose cotransporter 2 (SGLT2) inhibitor velagliflozin,a new drug with therapeutic potential to treat diabetes in cats          下载免费PDF全文

M. Hoenig  M. Clark  D. J. Schaeffer  D. Reiche 《Journal of veterinary pharmacology and therapeutics》2018,41(2):266-273

Sodium‐glucose cotransporter 2 (SGLT2) inhibitors are used in the treatment of human diabetics. They increase glucose excretion and correct hyperglycemia. We examined the investigational SGLT2 inhibitor velagliflozin in two groups of six neutered adult obese cats (equal gender distribution). Placebo (Pl) or drug (D; 1 mg/kg) was administered for 35 days. Routine blood examinations, fructosamine, beta‐hydroxybutyrate (BHB), nonesterified fatty acids (NEFA), glucagon, adiponectin, and leptin were measured before and after treatment, also water intake, and urinary electrolytes, glucose, and volume. Indirect calorimetry, an intravenous glucose tolerance test (IVGTT; 0.8 g/kg) and insulin tolerance test (IVITT) were conducted. All cats tolerated treatment well. Significant changes with D included a decrease in the respiratory exchange ratio, an increase in cholesterol, a small increase in albumin, and a rise in BHB and NEFA. Glucose clearance was unaltered, although less insulin was secreted during the IVGTT (p = .056) suggesting improved insulin sensitivity. IVITT was unchanged. Treatment did not affect glucagon, leptin, or adiponectin. Water intake, urine output, urinary glucose excretion, and the glucose/creatinine ratio but not urinary electrolytes were significantly higher post‐D. We conclude that velagliflozin is a promising drug, which increases urinary glucose excretion in cats and could thereby be beneficial for the treatment of hyperglycemia.  相似文献   

Estimated Breeding Value in Iranian Buffaloes     

M. R. Sanjabi  F. Alemi  H. R. Naderfard 《农业科学与技术》2011,(4):570-574

This study was conducted from 1992-2002 on 65,534 individual milk records and fat percentage in 473 herds, in six provinces of Khuzestan, Mazndaran, W. Azerbaijan, E. Azerbaijan, Ardabil and Gilan. The data was analyzed by SAS sotfware using GLM procedure. The heritability and breeding value of 1,195 animals were calculated by DFRML procedure. The average milk yield per lactation, days of lactation, fat percentage and LSM of fat percentage were 1,513 kg, 202 days, 5.04 and 6.77, respectively. The estimated heritability of milk was 0.16. The LSM of average milk production in the provinces of Gilan, Mazandaran, E. Azerbaijan, W. Azerbaijan, Khuzestan and Ardabil were： 1,452, 1,586, 1,382, 1,183, 2,135 and 1,189 kg, respectively. These results indicated that Khuzestan province has the highest potential in the field of milk production. The top five highest breeding value bulls have been introduced to artificial insemination＇s station in the city of Uremia.  相似文献   

围产期奶牛血钙影响因素及其与生产性能关系分析     

《中国畜牧杂志》2019,(11)

本试验旨在探究围产期奶牛血钙浓度影响因素及其与生产性能的关系。于2018年7月20日—8月15日对北京地区36头围产期健康荷斯坦牛的血钙浓度进行测定,收集该牛场奶牛生产性能测定(DHI)报告,利用固定效应模型分析不同胎次、体况评分(BCS)、健康状况及血钙浓度变异度对血钙浓度的影响。结果表明:血钙浓度与产后天数存在显著的正向相关关系;经产牛的血钙浓度(1.40 mmol/L)极显著高于初产牛(1.31 mmol/L);不同BCS分组奶牛血钙浓度差异不显著;健康组的血钙浓度(1.41 mmol/L)显著高于患病组(1.30 mmol/L);血钙浓度变异度的大小影响奶牛的产奶量,初产奶牛低变异度组的产奶量(16.70 kg/d)显著高于中变异度组(9.75 kg/d)和高变异度组(5.63 kg/d)。本研究进一步揭示了围产期荷斯坦牛血钙浓度的变化规律以及其影响因素,为预防奶牛产后低血钙症的发生以及制定提高奶牛生产性能的饲养管理策略提供参考。  相似文献   

Making Antibiotic Treatment Decisions for Clinical Mastitis     

《Veterinary Clinics of North America: Food Animal Practice》2018,34(3):413-425

  相似文献   

葡萄汁奶酒发酵工艺研究     

林少华  李星宇  罗红霞 《中国奶牛》2020,(2):55-59

本文以牛奶和葡萄为原料,通过单因素和正交试验优化了葡萄汁奶酒的发酵工艺。结果表明,影响葡萄汁奶酒感官评分因素的强弱顺序依次为发酵温度>接种量>发酵时间>蔗糖添加量>葡萄汁添加量,通过计算发现最佳组合为发酵温度25℃,发酵时间5d,接种量1.00%∶0.50%∶1.50%,蔗糖添加量8%,葡萄汁添加量11%。该组合酿制的葡萄汁奶酒感官评分最高,为92分。经测得,葡萄汁奶酒在最佳发酵工艺条件下的总糖为9.5g/L、酒精体积分数为6.8%,总酸质量浓度为7.2g/L,氨基酸态氮质量浓度为0.21g/L。该葡萄汁奶酒中的天门冬氨酸、谷氨酸、异亮氨酸、亮氨酸、赖氨酸和脯氨酸含量显著高于奶酒和牛奶中的含量(P<0.05)。  相似文献