In this study, the levels of aflatoxin M₁(AFM₁) in milk were determined by HPLC with derivatization method. Milk samples were purified using C∧18 disposable cartridge followed by derivatization with trifluoroacetic acid and analysed using HPLC with fluorescence detection. The recoveries of AFM₁ from milk samples added AFM₁ at a level of 0.025~0.1 ng/ml were 94.7~98.0% with detection limit of 0.009 ng/ml. The amounts of AFM₁ were determined below 0.05 ng/ml for all tested samples of commercial milk collected in 1999 and 2000.

A method for the quantification of eugenol in the medicinal herb Clove was developed and validated. For preparation of sample solutions clove was dried at 60℃ for 2h and ground by mixer and extracted with 95% ethanol for shaking extraction. The elutes were analyzed by HPLC system included a reversed phase column, a isocratic mobile phase of 60% methanol and PDA detector set at 280 nm. Calibration graphs were linear with very good correlation coefficients(r² greater then 0.9999) from 0.0125~1 ㎍/ml. The limit of detection per sample injection (20 ㎕) was 0.81 ng/㎕ and limit of quantification was 2.47 ng/㎕. The method showed good intra-day precision (%RSD 0.08~0.27%) and inter-day precision (%RSD 0.32~1.19%).

Measurement uncertainty could play an important role in the assessment of test results in laboratories and industries. We investigated measurement uncertainties possibly included in determination of flubendazole, a benzimidazole anthelmintic, in pork by HPLC. The concentration of flubendazole was 62.69 ng/g in a sample of pork. Uncertainty was estimated in the analytical procedure of flubendazole. A model equation was made for determination of flubendazole in pork. The four uncertainty components such as weight of sample, volume of sample, calibration curve, and recovery were selected to estimate measurement uncertainties.

This study was conducted to observe the occurrence of aflatoxin in chicken feed from Peninsular Malaysia. A total of 336 samples of chicken feed from Peninsular Malaysia were conveniently collected in this survey. The chicken feed represented the following three categories which are starter, grower and finisher. All samples werecollected from local poultry farms in East Coast Region (Kelantan, Terengganu, and Pahang), Northern Region (Perlis, Kedah, Penang, and Perak), Southern Region (Malacca, Johor) and Central Region (Selangor, Negeri Sembilan) of Peninsular Malaysia for a periodof six months (July-December 2015). Enzymelinked immunosorbent assay (ELISA) was used for screening of total aflatoxin (TA) in the samples. High performance liquid chromatography (HPLC) with fluorescence detector was used for determination of aflatoxin B and G. Moisture content of samples was determined using the hot airoven method (AOAC International, 2011). Overall, the incidence of positive TA >20 µg/kg in chicken feed is 14.9% (50 samples). The average level of TA was found significantly different between different states at p<0.05 for both broiler grower and finisher. Thechromatograph results showed that positive samples were found in broiler finisher from Kedah (94.6 µg/kg and 42.1 µg/kg) and Penang(56.4 µg/kg) with aflatoxin B1. In this study, the range of moisture content were around 6.5-27.3%. About 40% samples have more than12% moisture content. One of the predisposing factors for aflatoxin accumulation in chicken feed is moisture content. The results warrantthe need for surveillance and constant monitoring programmes for the prevention of aflatoxin incidence in poultry farms.

The present study was planned to evaluate the bioequivalence of two commercial formulations of enrofloxacin, which have been marketed as 10% injectable solution after intramuscular administration at a single dose of 2.5 mg/kg body weight to 12 clinically healthy goats The study was carried out on the basis of crossover design. The two formulations were: Baytril as a reference product and Spectrama Vet as a test product. The plasma concentrations of enrofloxacin were measured by high performance liquid chromatography (HPLC) with UV detector. The pharmacokinetics of that data was performed using non-compartmental analysis. The maximum plasma concentration (Cmax), time to reach peak concentration (Tmax), area under concentration-time curve (AUC), elimination half-life (t0.5el) were 1.14 and 1.05 μg/mL, 0.79 and 0.83 h, 5.70 and 5.79 μg.h/mL, 5.19 and 5.39 h for Baytril and Spectrama Vet, respectively. The 90% confidence interval for the mean ratio of Tmax, Cmax and AUC were 94.72~116.2, 87.88~97.16 and 86.44~118.72%, respectively. These values falls within the European Medicines Agency bioequivalence acceptance range of 80~125% for both Tmax and AUC and between 75~133% for Cmax. In conclusion, Spectrama-Vet is bioequivalent to Baytril and both products can be used as interchangeable drug in veterinary medicine practice.

We established a new method to analyze moxidectin using high performance liquid chromatography(HPLC) with fluorescence derivatization in order to obtain its residual profiles in biological samples. Recovery of moxidectin in tissue was 62% at 10 ppb. Average detection reproducibility in terms of coefficience variation was 4.47% at 0.32 to 10 ppb. Residual of moxidectin was studied in 44 Yorkshire-Landrace mixed bred male pigs administered subcutaneously 0, 200, or 800 ㎍/kg body weight (BW) Residual profiles of moxdectin in blood, muscle, liver, kidney and fat of pigs were described. The concentration of the moxidectin in liver after administration of moxidectin was the highest among the tissues examined.

The present study was undertaken to detect residues of Tetracycline in marketed pork using a High Performance Liquid Chromatography (HPLC) System and a UV-Vis Spectrophotometer. 300 samples of marketed pork were collected for the study. The samples after collection were preserved at -20°C. Analyses of the samples using High Performance Liquid Chromatography with UV-Vis Detector were done as per the method of Oka et al., 1985 while analyses of the same samples using UV-Vis Spectrophotometer were done as per the method of Yongnianian et al, 2010. Recovery ranged from 85-93% (HPLC) and 68-83% (Spectrophotometer). Out of the tested samples, 4 samples were detected to be positive for trace residues of tetracycline using Spectrophotometer while 6 samples were detected for tetracycline residues using HPLC method which were well below the Maximum Residue Limit (MRL) value. The method of HPLC is more sensitive than the Spectrophotometric one. Thus, the HPLC method is useful for monitoring of tetracycline residues in pork.&nbsp;

Ceftizoxime is the third generation cephalosporin, extensively used in veterinary medicine. It has larger volume of distribution, good penetration into tissues, and useful for the treatment of mastitis which is resistant to other antibiotics. Keeping in view of generating pharmacokinetic data of ceftizoxime in different domestic animals, the present study was planned to investigate pharmacokinetics of ceftizoxime in goats (n = 6) at the dose rate of 10mg kg-1 body weight following single dose intravenous administration. Drug concentration in plasma was determined using High Performance Liquid Chromatography (HPLC) with UV detector. The values of Cmax, AUC and MRT were 44.40 ± 2.09 µg ml-1, 121.22 ± 15.40µg.h.ml-1 and 11.44 ± 1.30 h, respectively. The longer elimination half-life (8.92 ± 1.11h) along with smaller ClB (0.09 ± 0.01 Lh-1 kg-1) showed slower excretion of the drug from animal body.&nbsp;

We have investigated the accumulation of diacylglycerol (DAG) induced by carbon tetrachloride (CCl4)-derived radicals in the liver of female Sprague-Dawley (SD) rats after intraperitoneally injecting CCl4. DAG is an intracellular activator of protein kinase C (PKC) which regulates cell proliferation and differentiation. The electron spin resonance (ESR) study gave the signal of the PBN-CCl3 adduct in the liver of the rats which were pretreated with PBN, confirming that CCl4 was metabolized into CCl3-radicals with cytochrome P450 enzyme and indicating that PBN could trap them. The blood biochemical assay supported the trapping of the CCl3-radicals; the pretreatment of rats with PBN inhibited the increase in the GOT and GPT values upon exposure to CCl4. The Fourier transform-infrared (FT-IR) study indicated in comparison with the model compounds that the CCl4-injected rats accumulated DAG in addition to phosphatidylcholine, phosphatidylethanolamine and triglyceride (TG) in the lipid membrane fraction of the liver homogenate. DAG was found to be ca. 10-15% of the membrane phospholipids by weight. However, DAG was not found in the lipid of the liver microsomes, suggesting that it is formed only in the cell membrane of liver. Also, neither DAG nor TG was found in the lipid membrane of the rats that were pretreated with PBN followed by an injection of CCl4. The formation of DAG was confirmed by an HPLC study. The activation of PKC was observed in liver homogenate in the rats that were injected with CCl4. On the basis of the above findings, it was concluded that the CCl4-derived radicals stimulate PKC through the accumulation of DAG in the liver membrane of the rats. Furthermore, it was shown that PBN has a protective and therapeutic effect against CCl4-induced damage