Feeds sampling

ASTM D-611 involves heating a 50/50 mixture of the feed sample and aniline until there is only one phase. The mixture is then cooled and the temperature at which the mixture becomes suddenly cloudy is the aniline point. The test senses solubility via a light source that penetrates through the sample. 

UOP Test Method 313 is commonly employed to determine the basic nitrogen content of FCC feed. The feed sample is first mixed 50/50 with acetic acid. The mixture is then titrated with perchloric acid. 

Feed sample [kg] About 0.8x10- About 1.0x10- ... 

Javier LU, Marazuela MD, Moreno-Bondi MC (2007) Molecularly imprinted polymers applied to the clean-up of zearalenone and a-zearalenol from cereal and swine feed sample extracts. Anal Bioanal Chem 385 1155-1161... 

In Nebraska, state regulations require that the chemical makeup of animal feed sold in the state be accurately reflected on the labels found on the feed bags. The Nebraska State Agriculture Laboratory is charged with the task of performing the analytical laboratory work required. An example is salt (sodium chloride) content. The method used to analyze the feed for sodium chloride involves a potentio-metric titration. A chloride ion-selective electrode in combination with a saturated calomel reference electrode is used. After dissolving the feed sample, the chloride is titrated with a silver nitrate standard solution. The reaction involves the formation of the insoluble precipitate silver chloride. The electrode monitors the decrease in the chloride concentration as the titration proceeds, ultimately detecting the end point (when the chloride ion concentration is zero). 

Charlie Focht of the Nebraska State Agriculture Laboratory refills a saturated calomel electrode with saturated potassium chloride while preparing to analyze animal feed samples for sodium chloride via a poten-tiometric titration. 

Contains the procedures and methods used in FDA labs for regulatory examination of food and feed samples to determine compliance with the FD C Act... 

A spectrophotometric method for determination of primary and secondary amines requires development for each particular compound, determining the kinetics of reaction of the amine with sodium l,2-naphthoquinone-4-sulfonate (143) and the UVV absorption spectrum of the product, under a set of fixed conditions. The procedure was applied to determination of ephedrine (30) and amphetamine (28) in pharmaceutical samples339. Reagent 143 in a FLA. system was used for the fast determination of lysine (144) in commercial feed samples by multivariate calibration techniques, without need of chromatographic separation340. 

A C30 RP column has been applied for the separation of carotenoids present in various matrices such as human serum, raw and thermally processed carrots, a Duniella algae-derived preparation and a poultry feed. Samples were mixed with deionized water and CaC03, homogenized and extracted with acetone-hexane (1 1, v/v). 

There are many variations on setting up the inlets to the MUX interface, depending on the needs of the laboratory. In one setup, one pump is used to deliver the flow through a flow splitter and multiple probe injector to four LC columns.The flow from each column is then fed into the MUX interface. In another variation, on-line SPE is coupled with LC. One pump, followed by a flow splitter, and one four-injector autosampler are used to feed samples into four extraction columns. A second pump is used (again with a flow splitter) to run gradients on the four LC columns into the MUX interface. In yet another system, an eight-channel UV MUX system is utilized. ... 

Custom-built, gravity feed sample input rack, equipped with a narrow-beam infra-red (IR) source/detector pair. 

Research in analytical chemistry is clearly an area where automation has a significant role to play. It is important that research data is fuUy validated and as accurate as possible. While it is not always possible to automate entire processes, the use of automated carousels to feed samples into a reaction system is an obvious area to improve the quality and rate of generation of data. It wiU also allow the researchers to quickly validate their proposed methodology on real-world samples and optimize the performance characteristics. This naturally requires a very close relationship between the researchers and the ultimate end-users of the analytical product. Given a good return for the investment, I am sure that the initial investment to automate the research activity will be justified and forthcoming. 

Note A typical ICP analysis requires making a solution of 9.6 ml ultra-pure water, 0.2 ml nitric acid (approximately 70% m/m HNO3), 0.1 ml marked feed sample solution (or 1 ml faecal sample solution) and 0.1 ml rhodium internal standard solution (10 pg mb in 5% v/v nitric acid solution). This is contained in a sample tube sealed with clingfilm. The sample probe is inserted through the clingfilm. A pick-up time of 35 s, and a scan time of 35 s proved satisfactory. The probe is rinsed in the 5% v/v nitric acid solution between samples. 

Hall, M.B., Jennings, J.P., Lewis, B.A. and Robertson, J.B. (2001) Evaluation of starch analysis methods for feed samples. Journal of the Science of Food and Agriculture 81,1 7-21. 

The two feeds for which the correlation gave the highest error are heavy, low API, and already preprocessed feed streams. One is DM0 from Gulf Coast and the other is Coker Gas Oil from Mid West. The H-NMR spectra features summarized in Figure 12.3a and b don t provide good clues about any special properties or features of the two feeds that resulted in the highest error for API prediction. One possible explanation for the poor API prediction for these two feeds is that in the analyzed set of feed samples the low API population was underrepresented. 

The refractive index (n) of a feed sample is proportional to its aromatic content the higher the value the more aromatic compounds are present in the feed. There are many methods to predict composition of petroleum products based on refractive index measurements [11]. The best linear regression model to predict refractive index (n) based on H-NMR spectra has the form ... 

In 1991, a survey of the swine sector in Italy noted a relatively high contamination of feedstuffs with veterinary drugs. The contamination concerned more than two-thirds of the controlled industrial animal feed producers (21). Not declared drugs, principally carbadox, olaquindox, and sulfamethazine, were found in 29 of 193 feed samples (15%) collected from 10 different feed producers. For some of these feeds, the relatively high drug levels could caused appearance of residues in the urine of the live swine and further in the offal taken from slaughterhouses. Positive findings in both urine and offal accounted for 10 of the 520 samples analyzed. 

Between 1993 and 1995, more than 250 farms were also inspected, and more than 4000 urine samples and 400 feeds were also examined for potential presence of -agonists (24). During that period, the percentage of positive urine samples from suspected animals decreased from 30% to less than 5%, and the percentage of positive feed samples was in the range 11-15%. Most positive samples contained clenbuterol and some mabuterol, bromobuterol, and salbutamol in addition to clenbuterol. In a few cases, more than one -agonist was detected in urine whereas various synthetic anabolic hormones were also found in feeds. 

Average results of analysis of feed samples and liquid effluent are shown in Table 9.4-1. 

Although MIPs can overcome these problems, no appropriate MIPs had been developed before, due to the high cost and the toxicity of these mycotoxins. The authors succeeded in synthesizing a good ZON mimicking template and made with it an MIP of suitable binding characteristics. This MIP has been applied for the analysis of cereal and swine feed samples. 

N. Garcia-Villar, J. Saurina and S. Hernandez-Cassou, Potentiometric sensor array for the determination of lysine in feed samples using multivariate calibration methods, Fresenius J. Anal. Chem., 371(7) (2001) 1001-1008. 

Table 5.2 Evaluation of field samples citrus pulp and citrus pulp containing animal feed samples measured by GC/MS and CALUX...

Under Annex IV of EU Council Regulation 2377/90 no MRL can be assigned to this compound and as such marketing authorisation for this compound has been withdrawn. However, under Directive 70/524EEC the compound is authorised for use only in turkeys and guinea fowl. No residues of this compound were detected in the 125 pig kidney samples analysed. However, dimetridazole was detected in pig feed samples at concentrations of 110/xg/kg, 130/xg/kg, 1,300 /xg/kg and 2,200 /xg/kg. 

This compound is currently licensed for use only in turkeys and guinea fowl as a feed additive and must not be used in laying hens. No residues of this compound were detected in liver samples (784) obtained from broilers, hens, ducks and turkeys. However, residues were found to be present in 25 broiler, three duck and one hen feed sample. In the future it is unlikely that this compound will continue to be authorised for use as a feed additive in any poultry species. 

In 1998, 3,678 samples were obtained from slaughterhouses (cattle, 1,171 pigs, 587 sheep, 242 poultry, 608) in addition feed samples (137) together with blood serum (185) and urine (285) were obtained from farms. Also in accordance with the revised EU Council Directive 96/23/EC fresh milk (210), eggs (150) and fish (5) samples were analysed. The result of this sampling and analysis programme was that 99.1% of samples were found not to contain detectable residues of veterinary drugs. In total 33 samples contained residues in excess of the MRL or action level. 

In many instances of mycotoxin analysis there is a great need for screening methods that can analyse large volumes of food and feed samples, most of which will be mycotoxin-free. It would also be extremely helpful if such methods could be used by relatively inexperienced operators and in situations where good laboratory facilities are not available (Table 11.5). 

In addition, USFDA analyzed 8731 animal feed samples from 1988 through 2003. No triazine detections were reported in any of the feed samples. Milk was also analyzed in the FDA monitoring program, and out of a total of 866 milk samples surveyed in 1991 and 1992, no triazine residues were detected (USFDA, 1991,1992). 

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