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41.

Background

Repeat patient testing‐based quality control (RPT‐QC) is a potential method for veterinary laboratories (eg, that have a limited budget for quality commercial control material [QCM] or that wish to use material with a species‐specific matrix).

Objectives

To determine whether total error (TEa), probability of error detection (Ped), and probability of false rejection (Pfr) similar to that achievable with QC materials can be controlled using RPT‐QC

Methods

Control limits (WBC, RBC, HGB, HCT, MCV, and PLT) for the Advia 120 (n = 23) and scil Vet ABC (n = 22) were calculated using data from normal canine specimens from a routine caseload. Specimens were measured at accession and again after 24 hours. Control limits were validated using 23 additional canine specimens tested similarly. Achievable TEa, Ped, and Pfr were investigated using the Westgard EZRules3 and compared to those achievable with commercial QCM.

Results

Theoretical performance of RPT‐QC and commercial QCM‐QC are similar for 1‐3s with both n = 1 and 1‐3s with n = 2 for all measurands and both instruments. Achievable TEa values for RPT‐QC were close to ASVCP recommendations for most measurands; exceptions were PLT (both instruments) and WBC (scil Vet ABC).

Conclusions

Repeat patient testing‐based quality control advantages include a species‐specific matrix, low‐cost, and absence of QC material deterioration over time (since a fresh specimen is used each day). A potential disadvantage is daily access to normal canine specimens. A challenge is determining control limits, which has a subjective element. Further study is needed to confirm actual RPT‐QC performance and to determine if RPT‐QC with abnormal patient specimens is feasible.  相似文献   
42.
This study was conducted to evaluate the effects of different levels of milk thistle meal on performance, blood biochemical indices, ileal bacterial counts and intestinal histology in laying hens fed diets containing different levels of metabolizable energy. A total number of 200 Leghorn laying hens (Hy‐Line W‐36) were randomly assigned to eight experimental treatments with five cage replicates of five birds each. Dietary treatments consisted of four levels of milk thistle meal (0%, 15%, 30% and 60%) and two levels of AMEn (11.09 and 12.34 MJ/kg) fed over a period of 80 days. In vitro studies revealed that the total phenolic component of milk thistle meal was 470.64 mg gallic acid equivalent/g of the sample, and its antioxidant activity for inhibiting the 2‐2‐diphenyl‐1‐picrichydrazyl free radical and reducing ferric ions was about 21% higher than that of butylated hydroxyltoluene (p < .05). Diets containing high level of AMEn led to improved egg production (p < .05), egg weight (< .05), egg mass (< .01) and feed conversion ratio (< .01). In addition, offering diets containing high energy significantly enhanced (< .01) serum triglyceride and malondialdehyde (MDA) concentrations as well as jejunal villus height. Dietary supplementation of 3% milk thistle meal resulted in the best feed conversion ratio (< .05), reduction of ileal Escherichia coli enumeration (< .01) and an enhancement in the villus height‐to‐crypt depth ratio (< .05). Furthermore, feeding incremental levels of this meal led to remarkable decrease in serum cholesterol, triglyceride and MDA (< .01) concentrations while significant increase in blood high‐density lipoprotein content and goblet cell numbers (< .05). The present findings indicate that milk thistle meal with high antioxidant and antibacterial properties in laying hen diets may improve health indices and productive performance.  相似文献   
43.
The objective of this study was to evaluate the effects of dietary supplementation with zinc oxide nanoparticles (ZnO‐NPs) on the performance, egg quality, Zn retention, immunity responses, superoxide dismutase activity (SOD), egg malondialdehyde (MDA) content, and serum parameters in laying hens in the late phase of production. A total of 288 laying hens at 64 weeks of age were randomly assigned to 4 treatments with 6 replicates, and 12 birds within each group. Experimental diets included a corn‐soybean meal‐based diet (without Zn supplementation) and a basal diet supplemented with 80 mg/kg of Zn‐oxide, ZnO‐NPs, and Zn‐methionine. The results indicated that egg production and egg mass were significantly higher in the Zn‐methionine and ZnO‐NPs groups (p < .05). Also, eggshell thickness and shell strength increased in the ZnO‐NPs group as compared with the other groups (p < .05). Moreover, Zn supplementation decreased egg loss (p < .05). There were significant differences among treatments in Zn deposition in tibiotarsus, liver, pancreas, eggs, and excreta (p < .01). Antibody titre, heterophil (%(, and phytohemagglutinin (PHA) were significantly higher in birds fed with Zn‐supplemented diets (p < .05). In treatments supplemented with ZnO‐NPs and Zn‐methionine, the SOD activity in the liver, pancreas, and plasma was greater as compared with the other treatments (p < .05). The MDA content in eggs was significantly reduced in groups supplemented with Zn (p < .01). Moreover, dietary Zn supplementation significantly affected serum total protein, albumin, glucose, alkaline phosphatase activity, carbonic anhydrase activity, and Zn level (p < .05). In conclusion, this study demonstrated that dietary supplementation with ZnO‐NPs can improve the performance of laying hens. Therefore, ZnO‐NPs can enhance zinc absorption in the intestine of aged layers and can be a more suitable source of zinc than regular Zn‐oxide in diets.  相似文献   
44.
This study was conducted to evaluate the comparative effect of maggot meal, silkworm meal and mealworm as dietary protein source on the production performance and some aspects of meat quality in broilers. In this regard, maggot meal was reared on chicken offal and poultry waste. Silkworm meal was obtained from silk industry, while mealworm was developed through beetles rearing. A total of 120‐day‐old broiler chicks were randomly divided into four groups where soya bean meal (M0) was replaced with maggot meal (M1), silkworm meal (M2) and mealworm (M3) respectively. Each group was further divided into three replicates. The study was carried out for a period of 5 weeks. Diets containing mealworm significantly reduced overall feed consumption and resulted into higher weight gain (p < .05). Lowest feed conversion ratio (FCR) was recorded for birds fed with mealworm diet (p < .05). Tenderness and juiciness of meat were higher (p < .05) in M3 compared to the control and other treatments. Mortality did not vary between the control and the treated groups. Therefore, it is concluded that insect meal is rich in essential nutrients and could be successfully used in broiler ration without compromising acceptability. In the light of this study, mealworm is the best choice in broiler ration, in comparison with maggot and silkworm.  相似文献   
45.
To study the effect of luteolin on blood indexes,liver and kidney in mice with acute mercury poisoning,28 mice were randomly divided into four groups:Control group (intraperitoneal injection 0.9% saline),luteolin group (lavage 100 mg/kg luteolin),mercuric chloride group (intraperitoneal injection 4 mg/kg mercury chloride) and mercury chloride+luteolin group (intraperitoneal injection 4 mg/kg mercuric chloride,lavage 100 mg/kg luteolin).The activities of ALT in serum,AST,CREA and BUN contents,blood WBC,RBC,HGB content and GSH and MDA contents of liver tissue were detected.Morphological changes of liver and kidney tissues were observed.The results showed that compared with the control group,the activities of ALT and AST of mercuric chloride group were extremely significantly increased (P < 0.01),serum CREA,BUN,blood WBC and liver tissue MDA contents were significantly increased (P < 0.05) while blood RBC,HGB and liver tissue GSH contents were significantly decreased (P < 0.05).Liver,kidney pathological changes were obviously.Compared with mercuric chloride group,the activities of ALT,AST in serum,CREA,BUN,blood WBC and liver tissue MDA contents of mercuric chloride+luteolin group were significantly decreased (P < 0.05),while blood RBC,HGB and liver tissue GSH contents were significantly elevated (P < 0.05).Liver,kidney pathological changes were attenuated obviously.The poisoning were characterized by inflammation and the occurrence of anemia when acute mercury poisoning occurred,liver and kidney showed different degrees of injury in mice.Luteolin could reduce the toxic effects of acute mercury poisoning on blood,liver and kidney.  相似文献   
46.
为探究异地育肥牦牛模式,本试验对比了低海拔异地育肥耗牛与本地杂交肉牛(秦川×西门塔尔)在同等条件下血液生理生化指标和生长性能的差异。将体重相近的8头1岁本地杂交肉牛(秦川×西门塔尔)和8头4岁青海牦牛各分为2组,每组4头,同一品种的2组试验牛分别饲喂低非蛋白氮饲粮[LNPN,饲粮中缓释尿素添加量为1.0%(干物质基础)]和高非蛋白氮饲粮[HNPN,饲粮中缓释尿素添加量为1.5%(干物质基础)]。预试期10 d,正试期50 d。结果发现:牦牛与肉牛均在LNPN条件下表现出最高的平均日采食量和最小的料重比。饲粮非蛋白氮水平未对牦牛与肉牛的血常规指标造成显著影响(P0.05),但是牦牛在各饲粮条件下中性粒细胞数目(Gran#)、平均红细胞体积(MCV)、平均红细胞血红蛋白含量(MCH)、红细胞分布宽度标准差(RDW-SD)、平均血小板体积(MPV)和血小板分布宽度(PDW)显著高于肉牛(P0.05),而平均红细胞血红蛋白浓度(M CHC)和血小板数目(PLT)显著低于肉牛(P0.05)。饲粮非蛋白氮水平未对肉牛和牦牛各项血清生化指标产生显著影响(P0.05)。牦牛在各饲粮条件下血清总蛋白(TP)、尿素氮(UN)、肌酐(GREA)、免疫球蛋白A(Ig A)、免疫球蛋白M(Ig M)和免疫球蛋白G(Ig G)水平均显著高于肉牛(P0.05)。牦牛在HNPN条件下的血清白蛋白(ALB)水平显著低于LNPN条件下(P0.05)。本试验结果表明,在肉牛和牦牛育肥饲粮中添加1.0%的缓释尿素替代饲粮蛋白质是可行的;低海拔异地育肥牦牛不会对牦牛健康产生不利影响。  相似文献   
47.
本试验旨在通过饲养试验和消化试验来评定红花粕和水飞蓟粕在生长獭兔上的营养价值。选取18只60日龄左右、平均体重(1.73±0.21)kg、健康状况良好的白色獭兔,随机分为3个组,每组6个重复,每个重复1只兔。各组分别饲喂基础饲粮、红花粕饲粮(85%基础饲粮+15%红花粕)和水飞蓟粕饲粮(85%基础饲粮+15%水飞蓟粕)。预试期和正试期各5 d。采用化学分析法测定红花粕和水飞蓟粕的总能(GE)及各营养物质含量,采用全收粪法测定生长獭兔对各营养物质的表观消化率。结果表明:红花粕和水飞蓟粕中的GE、干物质(DM)、粗蛋白质(CP)、粗纤维(CF)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)、酸性洗涤木质素(ADL)、粗脂肪(EE)、粗灰分(Ash)、钙(Ca)、磷(P)以及无氮浸出物(NFE)的含量分别为:18.81 MJ/kg、93.76%、23.94%、14.95%、19.92%、11.99%、2.19%、1.64%、4.93%、0.37%、0.57%、49.32%与17.12 MJ/kg、91.94%、23.62%、16.21%、38.57%、22.73%、4.04%、2.07%、5.31%、0.29%、0.68%、42.09%。生长獭兔对红花粕和水飞蓟粕中GE、DM、CP、CF、NDF、ADF、EE、Ash、Ca、P和NFE的表观消化率分别为62.60%、61.72%、62.39%、15.68%、26.30%、14.75%、80.69%、38.35%、59.35%、31.98%、79.61%与63.13%、61.94%、68.01%、15.74%、27.64%、14.98%、79.90%、38.20%、60.44%、32.99%、79.81%。由此可见,生长獭兔对红花粕和水飞蓟粕中的不同营养成分的表观消化率存在一定差异,结合2种原料各营养物质含量总体分析,2种原料均可作为獭兔的蛋白质饲料资源应用,并且对生长獭兔的营养价值相近。  相似文献   
48.
[目的]研究颗粒日粮中添加柠条对滩羊生长性能、血液生化指标、瘤胃发酵及羊肉品质的影响。[方法]选择体重相近的健康去势滩羊20只,随机分成两组,每组10只;对照组饲喂含有10%菊花粕的颗粒日粮,试验组饲喂含有6%柠条和4%菊花粕的颗粒日粮;开展周期为50天的育肥试验,测定滩羊的生长性能指标;育肥试验结束后,测定滩羊血液生化指标;屠宰后测定滩羊的屠宰性能指标,并取瘤胃液测定瘤胃发酵指标;取背腰最长肌,测定粗脂肪、粗蛋白、氨基酸含量以及脂肪酸组成。[结果]试验组和对照组滩羊的初始体重和终末体重无显著(P>0.05)差异;试验组平均日增重较对照组降低10.84%,差异不显著(P>0.05);对照组平均日采食量显著(P<0.05)高于试验组;两组试验羊料肉比相同。试验组滩羊血清中的总蛋白含量显著(P<0.05)高于对照组,其他血液生化指标无显著(P>0.05)差异。对照组滩羊屠宰率比试验组高1.59%,差异不显著(P>0.05);两组试验羊肝脏重、肝脏指数、心脏和肺脏重、心脏和肺脏指数差异不显著(P>0.05)。试验组滩羊瘤胃液中丁酸浓度显著(P<0.05)高于对照组,异戊酸浓度显著(P<0.05)低于对照组。对照组和试验组滩羊背腰最长肌中分别检测出18种和20种脂肪酸,粗蛋白含量分别为17.51%和20.92%,粗脂肪含量分别为3.22%和3.89%,总氨基酸含量分别为13.25%和14.09%。[结论]颗粒日粮中加入柠条对滩羊生长性能、血液生化指标和屠宰性能影响不明显,但可改善瘤胃发酵,丰富羊肉中脂肪酸组成及含量,增加肉中粗蛋白、粗脂肪和氨基酸含量。  相似文献   
49.
Two growth trials were conducted to evaluate and confirm the efficacy of a porcine meal (PM) with high protein content (>90%) as an alternative feed ingredient in commercial‐type feed formulation for Pacific white shrimp, Litopenaeus vannamei. Six experimental diets were formulated for the two growth trials. The first five diets contained increasing levels (0, 1, 2, 4, and 6%) of PM as a replacement for soybean meal in a plant‐based diet with low inclusion level (6%) of fish meal (FM). The last experimental diet was produced utilizing 4.2% PM to completely replace FM. In Trial 1, shrimp (1.5 g initial mean weight, 20 shrimp/tank, n = 4) were offered test diets for 6 wk in a semirecirculation system. At the end of Trial 1, shrimp fed with the diet containing 6% PM exhibited significantly enhanced weight gain (WG), feed conversion ratio (FCR), and survival compared to those fed with the diet devoid of FM. As survival was poor across all treatments and different densities could mask growth results the trial was repeated. In Trial 2, shrimp (0.85 g, 15 shrimp/tank, n = 4) were offered diets for 6 wk. Dietary supplementation of PM at 6% significantly improved WG, FCR, and apparent net protein retention in contrast with the treatment devoid of FM, confirming the same trends in Trial 1. No significant difference was detected in protein, lipid, moisture, and mineral profiles of whole‐body shrimp as well as survival across all the treatments. Results of this study indicate that PM is a good high protein source in shrimp feeds, which can be included up to 6% in the low FM‐based diet without compromising the growth of shrimp.  相似文献   
50.
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