Woody breast (WB) is a myopathy of the Pectoralis major muscle in broilers that is characterized by increased hardness of the raw fillet. This defect increases economic losses due to associated decreased meat quality and the addition of training skilled laborers to identify problematic fillets. Therefore, the objectives of this study were to determine if compression force (CF) could be used as a non-invasive method of detecting WB and to assess changes in meat attributes during cold storage. Deboned fillets (n = 121) were collected from 8-wk-old broilers, and categorized as normal (NORM, n = 42), mild (MILD, n = 39), and moderate/severe (SEV, n = 40) for WB. Right fillet weight, drip loss, and CF of the cranial region were measured on the day of processing (day 0) and 1, 2, 3, 4, and 8 d of cold storage (4°C). Left fillets were sampled for sarcomere length (SL) and gravimetric fragmentation index (GFI) analysis following 1, 3, and 8 d of cold storage. Initial breast fillet weight, CF, cumulative drip loss, and SL increased as severity of WB category increased (P < 0.05). Compression force was highly correlated to WB severity (rs = 0.79). Compression force, SL, and GFI declined with storage time (P < 0.05), whereas cumulative drip loss increased (P<0.05). Cumulative drip loss, SL, and GFI had interactions between storage length and WB category (P < 0.05), where SEV generally changed more than NORM over time. The results of this study indicate that increased severity of WB fillets is associated with higher CF compared to normal fillets. Furthermore, there is a softening effect of the meat over time and data suggest that moisture (drip loss) and myofibril proteolysis (fragmentation) contribute to these changes. Using instrumental CF to assess fillet hardness can be used as a reliable tool to identify WB. However, adaptability in the commercial processing require additional studies prior to the incorporation into the processing plant for online grading purposes.

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The objective of this study was to determine the effect of ensiling different ratios of whole crop oat to lucerne on fermentation quality, aerobic stability and in vitro digestibility of silage on the Tibetan plateau. Four experimental treatments were produced varying in the ratio of forages on a fresh matter (FM) basis: 1) 100% oat (control, dry matter (DM) content: 317 g/kg), 2) 90% oat + 10% lucerne (OL10, DM content: 316 g/kg), 3) 80% oat+ 20% lucerne (OL20, DM content: 317 g/kg) and 4) 70% oat+ 30% lucerne (OL30, DM content: 318 g/kg). All treatments were packed into laboratory-scale silos and ensiled for 60 days and then subjected to an aerobic stability test for 15 days. Further, the four experimental treatments were incubated in vitro with buffered rumen fluid to study the nutrient digestibility. All silages were well preserved with low pH and NH -N contents, and high lactic acid contents and V-scores (evaluation of silage quality). Increasing the lucerne proportion increased (p < 0.05) crude protein (CP) content of silage, whereas neutral (NDF) and acid (ADF) detergent fibre contents were not affected. Under aerobic conditions, the control silage showed higher (p < 0.05) yeast counts (>10 cfu/g FM) followed by OL10 silage, and OL10 silage improved aerobic stability for 74 h. OL20 and OL30 silages showed fewer (p < 0.05) yeasts (<10 cfu/g FM) and markedly (p < 0.05) improved the aerobic stability (>360 h). After 48-h incubation, OL30 silage increased (p < 0.05) in vitro dry matter digestibility (IVDMD) and neutral detergent fibre digestibility (IVNDFD) compared with the control silage. These results suggest that replacing oat with lucerne had no unfavourable effects on fermentation quality of silage, but improved CP content, aerobic stability IVDMD and IVNDFD. OL30 silage was the best among the three mixed silages.

One of the current myopathies affecting the chicken meat industry is deep pectoral myopathy ( DPM ), also known as green muscle disease or Oregon disease, the condition is considered a major problem in poultry processing lines. Thus, the present study proposes to examine the meat quality of the Pectoralis major muscle (breast fillet) from carcasses of broilers affected by DPM in Pectoralis minor muscle (tender) and from a control group. Breast fillets samples were harvested from Ross AP95 broilers that were slaughtered at 42 days of age and were selected to the occurrence of the myopathy (score 2 and score 3) and from a control group without (score 0) the presence of myopathy. Chemical composition, cholesterol, fatty acid profile, pH, color, water-holding capacity, cooking loss, shear force, sarcomere length, and collagen were analyzed in the breast fillet. And with the results it was observed the samples classified as DPM score 2 had a higher moisture and a lower protein percentage. The higher values lipid was found in the samples from broilers affected by DPM. There was no difference ( P > 0.05) fatty acid profile only to C10:0, C15:0, C17:0, C20:0, and C18:2c9,t11. Differences were detected ( P < 0.05) for the pH, WHC, SF, and sarcomere length of the samples from broilers affected by DPM. The higher pH observed in the samples from birds classified as DPM score 2 and the higher WHC values were observed in the samples affected by DPM (score 2 and 3). The SF ( P < 0.05) among samples, with the most tender samples (lower SF values) being those unaffected by the condition DPM (score 0). The dorsal side surface, where the Pectoralis major muscle is in contact with the Pectoralis minor muscle, higher L* values were found in the meat affected by the myopathy. Although deep pectoral myopathy affects the Pectoralis minor muscle of broilers, it can also alter the qualitative characteristics and chemical composition of the breast fillets ( Pectoralis major muscle).

The stem-loop potential of a nucleic acid segment (expressed as a FONS value), decomposes into base composition-dependent and base order-dependent components. The latter, expressed as a FORS-D value, is derived by subtracting the value of the base composition-dependent component (FORS-M) from the FONS value. FORS-D analysis is the use of FORS-D values to estimate the potential of local base order to contribute to a stem-loop structure, and it has been used to investigate the relationship between stem-loop structure and other selective pressures on genomes. In the present study, we evaluated the reliability of FORS-D analysis by comparing it with statistically significant stem-loop potential, another robust method developed by Le and Maizel for examining stem-loop structure. We found that FORS-M values calculated using 10 randomized sequences are as reliable as those calculated using 100 randomized sequences. The resulting FORS-D values have a similar trend and distribution as statistically significant stem-loop potential, implying that FORS-D analysis is as reliable as the latter in measuring the distribution of base order-dependent stem-loop potential. Since the calculation of the FORS-M values is time consuming, the integrated program Bodslp developed by us will become a convenient tool for large-scale FORS-D analysis. The results also suggest that for some purposes the online program SigStb developed by Le and Maizel may be used as an alternative tool for FORS-D analysis.