Studies On The Effects Of White Oil On Meat Quality And Its Residues Elimination In Chicken

This experiment was conducted to determine the effects of white oil on meat quality, serum biochemical indexes and antioxidation of Yellow broilers; And a method was developed for the deteilmination and identification of white oil residues (n-alkanes) in broiler muscle, using urea adduction fractionation-gas chromatography mass spectrometry; According to this method, residual elimination curve of white oil in broiler breast muscle was also developed. This experiment will be great significant for the establishment of white oil residue criterion and scientific use of oil emulsion vaccine in poultry industry. Research results are as follows:1. A study on the effects of white oil on meat quality, serum biochemical indexes and antioxidation of broilers. Two hundred1-day-old Yellow broilers were randomly divided into4groups, with5replicates of10broilers each group. According to the process of immune, at7,10,14,21and30days, the control group were injected with the saline solution; the live vaccines group were corresponding vaccinated with the live vaccine and injected with the saline solution; the oil emulsion vaccine group were corresponding injected with the oil emulsion vacpine; the white oil group were injected with the white oil. Each group was randomly selected20broilers for samples collection after42days, and the pH and the shear force of breast muscle and leg muscle, IMF (Intramuscular fat) and IMP of the breast muscle, serum biochemical indexes and antioxidation were measured. The result showed that the injection of the white oil would also significantly reduce the pH of the breast muscle and leg muscle and IMF of the breast muscle of broilers injected the white oil compared with the control group (P<0.05), but the shear force of breast muscle and leg muscle and the contents of IMP and IMPc were no significant different between each group (P>0.05).The levels of TP, ALB, BUN, SOD, GSH-PX and MDA of broilers injected the white oil were no significantly different compared with other groups (.P>0.05), but it could significantly improve the levels of TG, INO and decrease the levels of GLB in the white oil group (P<0.05). The result of this research suggested that the white oil could significantly increase the levels of TG, HYP and reduce the content of IMF, INO, moreover, it also had adversely effects on meat quality and serum antioxidation of broilers to a certain degree.2. A method was developed for the determination and identification of white oil residues (n-alkanes) in broiler muscle, using urea adduction fractionation-gas chromatography mass spectrometry (GC-MS). Through the single factor experiments, the optimization of urea adduction was selected as the purification method. Homogenized broiler muscle samples were purified with urea adduction after extracted with n-hexane, then separated on a Agilent DB-lms capillary column (60.0m×0.25mm×0.25μm) using temperature programming. The oven temperature was programmed at20℃/min from100℃(hold1min) to200℃(hold1min), then programmed to320℃at8℃/min and held at320℃for5min. The full scan/select ion mode were selected as the mode of mass spectrometric detection, and the ions for quantitative determination were226.0,240.0,254.0,268.0.284.0,292.0,310.0,324.0,338.0. The results showed that the best method of extraction is a mechanical vibration (0.5h×2times), the best dissolved reagent is dichloromethane, the best adduction temperature is4℃, the optimum washing reagent is isooctane; The limits of detection (LODs, S/N=3) were25μg/kg and the limits of quantitation (LOQs, S/N=10) were50μg/kg for n-alkanes in the white oil, and with a good linearity (R2≥0.99) ranged from200μg/L～5mg/L in this method. And the average recoveries (n=6) of the mixed standard of n-alkanes spiked in the broiler muscle samples ranged from65.16%to91.25%with the relative standard deviations (RSDs) between2.23%～12.50%.The method was applied for the qualitative and quantitative determination of the practical positive sample of broiler muscle with sensitive and accurate characteristics.3. A study on residual elimination curve of white oil (n-alkanes) in broiler breast muscle. Fifty15-days-old Yellow broilers were injected with the white oil in broiler breast muscle. Five broilers were selected for breast muscle samples collection after3,7,10,14,21,28,35and42days, and the n-alkanes contents in breast muscle were measured and the residual elimination curves of white oil (n-alkanes) in broiler breast muscle were developed. The result showed that the n-alkanes contents in breast muscle were gradually reduced after injecting with the white oil; During0～7d, all n-alkanes in broiler breast found a rapid decline relatively, especially for short chain alkanes; After42days, the contents of the short-chain alkanes have fallen below the limit of detection, and the long chain alkane still have remaining; Relative to the short chain alkanes, the eliminate curves of the long chain alkane shows a gentle decline, and it is need more time for migration or elimination in the chicken than the short chain alkanes.