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Shokuhin Eiseigaku Zasshi. Journal of... 2024The present study verified that it is possible to analyze melengesterol acetate using the existing multi-residue method. Melengestrol acetate was extracted from...
The present study verified that it is possible to analyze melengesterol acetate using the existing multi-residue method. Melengestrol acetate was extracted from livestock products using acidic acetonitrile acidified with acetic acid in the presence of n-hexane and anhydrous sodium sulfate. The crude extracts were cleaned up using an octadecylsilanized silica gel cartridge column. Separation by HPLC was performed using an octadecylsilanized silica gel column with linear gradient elution of 0.1 vol% formic acid and acetonitrile containing 0.1 vol% formic acid. For the determination of the analyte, tandem mass spectrometry with positive ion electrospray ionization was used. In recovery tests using four livestock products fortified with maximum residue limits levels of melengestrol acetate (0.001-0.02 mg/kg), the truenesses ranged from 82% to 100%, and the repeatabilities for the entire procedure ranged from 0.5 RSD% to 5.6 RSD%. In recovery tests using 11 livestock products fortified with 0.0005 mg/kg of melengestrol acetate, the truenesses ranged from 88% to 99%, and the repeatabilities ranged from 1.3 RSD% to 5.4 RSD%. The limit of quantification for melengestrol acetate in livestock products was 0.0005 mg/kg.
Topics: Animals; Liquid Chromatography-Mass Spectrometry; Melengestrol Acetate; Chromatography, Liquid; Livestock; Silica Gel; Tandem Mass Spectrometry; Acetonitriles; Formates
PubMed: 38432897
DOI: 10.3358/shokueishi.65.15 -
Journal of Agricultural and Food... Jun 2023Gestagens, a class of veterinary drugs also called progestogens, are synthetic hormones used to increase feed efficiency and rate of gain in heifers. The Canadian Food...
Gestagens, a class of veterinary drugs also called progestogens, are synthetic hormones used to increase feed efficiency and rate of gain in heifers. The Canadian Food Inspection Agency analyzes progestogens melengestrol acetate (MGA), megestrol acetate, and chlormadinone acetate using liquid chromatography-mass spectrometry (LC-MS). Our conventional gestagen method for kidney fat has many time-consuming steps, including solid-phase extraction. A sample preparation procedure having fewer clean-up steps was developed for routine diagnostic analysis of kidney fat and provided similar results faster, and at lower cost. A confirmatory liver method for gestagens, developed using salt-assisted extraction, employed minimal clean-up steps that resulted in high chemical background at the desired lower limit of quantification (LLOQ). Differential ion mobility spectrometry, specifically high-field asymmetric waveform ion mobility spectrometry (FAIMS), was used to filter chemical background in the gas phase. The effect of the ionization probe position on FAIMS parameters, including sensitivity, is described. With LC-FAIMS-MS, chemical background for each gestagen was virtually eliminated, resulting in a quantitative liver method having the desired 0.6 ng/g LLOQ and estimated limits of detection (LODs) up to 140 times lower than LC-MS. Incurred MGA samples, analyzed using kidney fat and liver methods from the same animal, show levels within the quantitative ranges of both methods.
Topics: Animals; Cattle; Female; Progestins; Canada; Chromatography, Liquid; Mass Spectrometry; Melengestrol Acetate; Liver
PubMed: 37319426
DOI: 10.1021/acs.jafc.3c01200 -
Scientific Reports Oct 2023The present study aimed to test the efficiency of transcervical artificial insemination techniques with cervical immobilization (TCAI-CI) or cervical traction (TCAI-CT),...
The present study aimed to test the efficiency of transcervical artificial insemination techniques with cervical immobilization (TCAI-CI) or cervical traction (TCAI-CT), associated or not with the use of oxytocin (OT) as a protocol for cervical dilation, in the brown brocket deer (Subulo gouazoubira). The study was carried out in a crossover design using four adult females in two replicates with an interval of 60 days. Estrus was synchronized with oral melengestrol acetate (MGA) associated with estradiol benzoate and sodium cloprostenol. TCAI techniques were performed from 18 to 24 h after estrus onset. All females received either an i.v. application of 50 IU of OT (G-OT, n = 4) or 1 mL of saline solution (G-Control, n = 4) 20 min before the TCAI procedure. The TCAIs were performed using frozen-thawed semen motility 40%, vigor 3, acrosome integrity 87%, membrane integrity of 95% and 13% of total post-thaw defects from the same batch. Behavioral estrus was observed in 100% of the females, in both replicates. It was achieved a 50% (4/8) success of cervical transposition with semen deposition in the uterine. Regarding inseminations, most of them (87.5%) were performed using the TCAI-CT technique, and the overall conception rate was 50%. Cervical transposition times (< 1 min) and TCAI procedures (~ 17 min) were considered satisfactory. Thus, the performance of the TCAI-CI and TCAI-CT techniques was successful, regardless of using OT as a cervical dilation protocol. This procedure is proposed as a method of choice for artificial insemination with greater applicability in different conservation centers, compared to more advanced reproductive biotechniques, and with a favorable impact on the conservation of deer species.
Topics: Animals; Female; Male; Cervix Uteri; Deer; Insemination, Artificial; Oxytocin; Semen Preservation; Uterus; Cross-Over Studies
PubMed: 37833322
DOI: 10.1038/s41598-023-43392-4