Increased hepatic aryl 4-monoxygenase in chickens caused by lipophilic xenobiotics

Hens were treated with three types of lipophil xenobiotics - polychlorinated biphenyl (PCB), lindane and hexachlorobenzene (HCB) - to study changes in the levels of microsomal proteins and in the activity of microsomal aryl 4-monooxygenase in liver. The above foreign substances were given in feed at a dose of 50 mg per kg during a fortnight. The level of microsomal proteins in liver increased after seven-day administration of xenobiotics and was always higher in the course of the experiment than in the controls. The activity of the microsomal enzyme (aryl 4-monooxygenase) was significantly higher in treated hens after seven- and 14-day interval, and also seven days after the end of feeding the contaminated feed mixture. Inductive properties were strongest in polychlorinated biphenyl (Delor 103), but lindane and hexachlorobenzene also induced a statistically significant rise, in comparison with the controls. It is shown that the inductive ability of lipophil xenobiotics is stronger in hens than in chicks, which may influence the metabolism of some biologically important substances in poultry organism.     

喂料后称重肉种母鸡

在美国,大多数家禽生产商采取隔日饲喂方案来控制种用小母鸡体重。在当前鸡舍条件下,隔日饲喂方案是给所有鸡均匀分配饲料最好的方法,以保证鸡群均匀度。但是,嗉囊或者消化道内有食物会使鸡只的实际体重增加而且随着时间延长消化道内饲料逐渐减少。因此,后备种鸡一般在未采食的那天进行称重以规范数据,将体重与嗉囊或者消化道内有无饲料分开。然后每周在固定时间称重。这样称得的体重称为“空腹”体重。     

Chemical marker for ALS-inhibitor herbicides: 2-aminobutyric acid proportional in sub-lethal applications

A chemical profiling technique for sub-lethal acetolactate synthase (ALS)-inhibitor herbicides (e.g., sulfonylureas, imidazolines, triazolopyrimidine sulfonanilides, and pyrimidyloxy salicylic) was developed using 2-aminobutyric acid, and was found to be directly proportional to application rates in field studies on two varieties of potato plants. An uncomplicated, benign-by-design analytical method for the determination of 2-aminobutyric acid in plant tissue was developed. The method is simple, fast, and automated, entailing a water-trichloroacetic acid extraction followed by precolumn on-line derivatization using o-phthalaldehyde (OPA) solution and liquid chromatographic analyses. Use of reagents and chlorinated organic solvents, and generation of waste, are minimized as compared to other ALS-inhibitor herbicide analytical techniques. Recoveries for a series of fortified plant tissues ranged from 82 to 103%. Two 20-day field trials on two potato varieties, Russet Burbank and Shepody, were conducted during the 2000 and 2001 growing seasons. The study demonstrated that the 2-aminobutyric acid method is an excellent, selective chemical marker technique for ALS-inhibitor herbicides for real world plant matrixes.     

Predicting Soil Electrical Conductivity of the Saturation Extract from a 1:1 Soil to Water Ratio

Since 1954, the electrical conductivity of the saturated paste extract (ECe) has been the preferred index for soil salinity. Based on this value, remediation strategies were developed and widely used but this approach is time consuming and not routinely offered by many soil testing facilities. However, many laboratories determine the EC_1:1 value of a 1:1 soil to solution ratio extract. The objective of this study was to identify the relationship between ECe and EC_1:1 and determine if EC_1:1 can be used as a proxy in the northern Great Plains for ECe. Samples were collected across five studies and from AGVISE Laboratory. The samples were analyzed for EC_1:1 and ECe. The relationship between the ECe and EC_1:1 showed that soil parent materials need to be considered in the conversion of EC_1:1 values to ECe values. A failure to consider parent materials in this conversion may have short and long-term sustainability ramifications.