The purpose of this study was to identify porcine-specific peptide markers from thermally processed meat that could differentiate pork from beef, chevon and chicken meat. In the initial stage, markers from tryptic digested protein of chilled, boiled and autoclaved pork were identified using LC-QTOF-MS. An MRM method was then established for verification. A thorough investigation of LC-QTOF-MS data showed that only seven porcine-specific peptides were consistently detected. Among these peptides, two were derived from lactate dehydrogenase, one from creatine kinase, and four from serum albumin protein. However, MRM could only detect four peptides (EVTEFAK, LVVITAGAR, FVIER and TVLGNFAAFVQK) that were consistently present in pork samples. In conclusion, meat species determination through a tandem mass spectrometry platform shows high potential in providing scientifically valid and reliable results even at peptide level. Besides, the specificity and selectivity offered by the proteomics approach also provide a robust platform for Halal authentication.

(2016) Skeletal muscle proteome and meat quality of broiler chickens subjected to gas stunning prior slaughter or slaughtered without stunning, CyTA -Journal of Food, 14:3, 375-381, DOI: 10.1080/19476337.2015 To link to this article: https://doi.org/10. 1080/19476337.2015 The study examined the effects of pre-slaughter gas stunning and slaughter without stunning on meat quality and skeletal muscle proteome of broiler chickens. Fifty Cobb broiler chickens were randomly assigned to either a neck cut without pre-slaughter stunning (Halal slaughter) or preslaughter gas stunning followed by a neck cut. Samples of Pectoralis major muscle at 7 min, 4 h and 24 h postmortem were analyzed for pH, shear force, color, drip and cooking losses. Proteome profile of the 7 min samples was examined by two-dimensional polyacrylamide gel electrophoresis. Birds subjected to Halal slaughter had higher (P < 0.05) redness than those gas stunned at 4 and 24 h postmortem. Gas-stunned birds had lower (P < 0.05) muscle pH and shear force and higher (P < 0.05) drip and cooking losses compared with those subjected to Halal slaughter throughout postmortem storage. Gas stunning up-regulated (P < 0.05) the expression of beta-enolase, pyruvate kinase and creatine kinase compared with Halal slaughter. Results indicate that pre-slaughter gas stunning hastened postmortem energy metabolism and had detrimental effects on the water holding capacity and redness of broiler breast muscles.Proteoma del músculo esquelético y calidad de la carne de pollos de engorde sujetos a aturdimiento por gas previo a la matanza o bien matados sin aturdimiento RÉSUMÉ Este estudio examinó los efectos de la matanza con previo aturdimiento por gas y la matanza sin aturdimiento en la calidad de la carne y el proteoma del músculo esquelético en pollos de engorde. Cincuenta pollos de engorde de Cobb fueron asignados de forma aleatoria para cortarles el cuello sin previo aturdimiento (matanza Halal) o con aturdimiento con gas previo a la matanza antes de cortarles el cuello. Se analizaron las muestras del músculo pectoral mayor a 7 min, 4 h y 24 h postmortem para el pH, la fuerza cortante, el color, la pérdida por goteo y de volumen en el cocinado. Se examinó el perfil del proteoma de las muestras de 7 min mediante dos electroforesis en gel poliacrilamida dimensionales. Las aves que estuvieron sujetas a matanza Halal tuvieron un color rojizo más fuerte (P < 0,05) que aquellas a las que aturdieron con gas después de 4 y 24 h postmortem. Las aves que aturdieron con gas tuvieron menor pH y fuerza cortante (P < 0,05) en el músculo y mayores (P < 0,05) pérdidas por goteo y de volumen en el cocinado en comparación con aquellas sujetas a matanza Halal mediante almacenamiento postmortem. El gas de aturdimiento reguló a la alta (P < 0,05) la expresión enolasa beta, la piruvatocinasa y la creatina quinasa en comparación con la matanza Halal. Los resultados indicaron que el aturdimiento por gas previo a la matanza aceleró el metabolismo de la energía postmortem y tuvo efectos perjudic...

This experiment aimed to determine microbial spoilage and lipid and protein oxidation during aerobic refrigerated (4°C) storage of rabbit meat. Forty male New Zealand white rabbits were slaughtered according to the Halal slaughter procedure. The hind limbs were used for microbial analysis while the Longissimus lumborum m. was used for determination of lipid and protein oxidation. Bacterial counts generally increased with aging time and the limit for fresh meat (10(8)cfu/g) was reached at d 7 postmortem. Significant differences in malondialdehyde content were observed after 3d of storage. The thiol concentration significantly decreased with increase in aging time. The band intensities of myosin heavy chain and troponin T significantly reduced with increased refrigerated storage while actin remained relatively stable. This study thus proposes protein oxidation as a potential deteriorative change in refrigerated rabbit meat along with microbial spoilage and lipid oxidation.

Corynebacterium pseudotuberculosis is the causative agent of caseous lymphadenitis (CLA) which commonly affects sheep and goats. The disease remains as a major disease causing economic loss to the small ruminant industries. There is little information related to responses of interleukin-1β and interleukin-6 in the chronic states. This study was designed to determine the serum concentrations of interleukin-1β and interleukin-6 (pg/mL) in nonpregnant does experimentally inoculated with Corynebacterium pseudotuberculosis via intradermal route in chronic form. Eighteen non-pregnant healthy Katjang does aged 2 years old were divided randomly into two groups. The control and the treatment groups consist of nine does each and were kept for 3 months. The control group was inoculated with PBS solution while the treatment group was inoculated intradermally with C. pseudotuberculosis. Serum samples were collected every 3 days (72 hours) for 3 months (2064 hours). The present study showed significant increase in IL-1β (278 ± 19.19 pg/mL) after 1day (24 hours) of post infection (p<0.0001) which decreased sharply (98.31 ± 19.19 pg/mL) after 5 days (120 hours) of post infection (p = 0.9293) and attained a significant concentration (217.43 ± 19.19 pg/mL) after 3 months (2064 hours) of post infection (p<0.0048) in does challenged with C. pseudotuberculosis compared to the control group. In contrast, the concentration of IL-6 increased significantly (p<0.0001) to (56.43 ± 1.98 pg/mL) in 2 months (1392 hours) of post infection and then decreased significantly (p<0.0001) to concentration of (22.18 ± 1.98 pg/mL) in 3 months (2064 hours) compared to the control group. In conclusion, the present study indicate that the importunity of C. pseudotuberculosis is associated with persistently high concentrations of IL-1β and low concentration of IL-6 which, when interpreted, could severely contribute to pathological vicissitudes and injury of organs and tissues in the chronic stage of C. pseudotuberculosis infections.

Corynebacterium pseudotuberculosis is the causative agent of caseous lymphadenitis (CLA), a common disease in small ruminant populations across the globe. The disease remains as a major disease causing economic loss to the owners. There is little information related to the effect of this disease towards reproductive performance of the animal when the disease occurs in chronic form. This study analyzes the changes of the reproductive hormones in nonpregnant does infected chronically with Corynebacterium pseudotuberculosis via intradermal route. Eighteen non-pregnant healthy Katjang does aged 2 years old were divided randomly into two groups. The first and second groups consist of nine does each and were kept for 3 consecutive months. The first group was experimentally inoculated with 1 ml of 107 cfu of live Corynebacterium pseudotuberculosis through intradermal route while the second group was inoculated with 1 ml PBS (pH 7) solution intradermally. Serum samples were collected every 3 days for 3 consecutive months from each group post infection via jugular venipuncture for reproductive hormone analyses. Present study indicates a decrement in progesterone concentration but shows an increment in estradiol profile throughout 3 months post-infection. The present results therefore indicate hormonal imbalance due to chronicity of Corynebacterium pseudotuberculosis in affected does.