Fiber Metabolism, Procollagen and Collagen Type III Immunoreactivity in Broiler Pectoralis Major Affected by Muscle Abnormalities

Abstract

The present study aimed to evaluate the muscle fiber metabolism and assess the presence and distribution of both procollagen and collagen type III in pectoralis major muscles affected by white striping (WS), wooden breast (WB), and spaghetti meat (SM), as well as in those with macroscopically normal appearance (NORM). For this purpose, 20 pectoralis major muscles (five per group) were selected from the same flock of fast-growing broilers (Ross 308, males, 45-days-old, 3.0 kg live weight) and were used for histochemical (nicotinamide adenine dinucleotide tetrazolium reductase (NADH-TR) and alpha-glycerophosphate dehydrogenase (α-GPD)) and immunohistochemical (procollagen and collagen type III) analyses. When compared to NORM, we found an increased proportion (p < 0.001) of fibers positively stained to NADH-TR in myopathic muscles along with a relevant decrease (p < 0.001) in the percentage of those exhibiting a positive reaction to α-GPD. In addition, an increased proportion of fibers exhibiting a positive reaction to both stainings was observed in SM, in comparison with NORM (14.3 vs. 7.2%; p < 0.001). After reacting to NADH-TR, SM exhibited the lowest (p < 0.001) cross-sectional area (CSA) of the fibers (−12% with respect to NORM). On the other hand, after reacting to α-GPD, the CSA of WS was found to be significantly larger (+10%) in comparison with NORM (7480 vs. 6776 µm2; p < 0.05). A profound modification of the connective tissue architecture involving a different presence and distribution of procollagen and collagen type III was observed. Intriguingly, an altered metabolism and differences in the presence and distribution of procollagen and collagen type III were even observed in pectoralis major muscle classified as NORM.

Weighted gene co-expression network analysis identifies molecular pathways and hub genes involved in broiler White Striping and Wooden Breast myopathies

“…In contrast, to date, little is known about COL4A1 and COL4A2 genes in chickens. Nevertheless, based on their possible involvement in breast abnormalities onset, other types of collagen are being recently studied in fast-growing broilers: Collagen type VI 16 and III 39 .…”

Comparison of muscle fiber characteristics and glycolytic potential between slow- and fast-growing broilers

“…Many previous studies have shown the growth performance, carcass characteristics, and meat quality of fast- and slow-growing commercial broilers ( Choo et al., 2014 ; Zhao et al., 2019 ; Biesek et al., 2020 ). However, there are only a few studies conducted on the comparison of muscle fiber characteristics and GP of breast and thigh muscles from fast- and slow-growing commercial broilers ( Zhao et al., 2012 ; Verdiglione and Cassandro, 2013 ; Shu et al., 2017 ; Mazzoni et al., 2020 ; Weng et al., 2022 ).…”

Spaghetti Meat Abnormality in Broilers: Current Understanding and Future Research Directions

“…A recent study also investigated the distribution of collagen type III and its precursor (i.e., procollagen type III) in SM samples since, being involved in fibrillogenesis, their possible altered deposition might have a key role in the occurrence of muscular abnormalities. In this regard, the findings highlighted an altered immunoreactivity to procollagen type III in SM samples, suggesting a compromised collagen turnover and synthesis (Mazzoni et al, 2020).…”

“…Moreover, histological observations highlighted the presence of small and thin fibers, interspersed by immature/newly deposited connective tissue (Baldi et al, 2018;Sanden et al, 2021). The presence of these fibers, distinguished by a remarkably reduced cross-sectional area, suggests the ongoing of regenerative processes taking place in the muscle, as a natural response mechanism to cell necrosis (Mazzoni et al, 2020). However, a different phase of cell regeneration can be hypothesized when comparing SM and WS samples' immunoreactivity to vimentin, suggesting a different progression of the regenerative processes (Soglia et al, 2020).…”