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White striping and wooden breast myopathies in broiler chickens: insights into possible causes and predisposing factors, muscle pathological lesions and implications on meat quality
Full text linkWhite Striping (WS) and Wooden Breast (WB) are two emerging myopathies in broiler hybrid chickens, which are gaining great relevance for the poultry sector, due to the huge economical losses ascribable to the unappealing appearance and impaired nutritional and technological quality of af-fected fillets. However, the knowledge concerning their aetiology is not clear and the consequences on meat quality is still incomplete. Therefore, the present thesis, which includes four researches, aimed to deepen the knowledge possessed by the scientific community on these defects. The first study in-vestigated the effects of WB myodegeneration on hybrid chickens meat quality and contributed in typifying macroscopic and histologic lesions. To this purpose, weight, cross sectional area (CSA), pH, L*, a*, b* colour values, water-holding capacity, and Warner-Bratzler shear force were deter-mined on 30 normal and 30 WB breasts (Pectoralis major muscle). In addition, samples were visually and histologically evaluated. Affected samples were heavier, thicker, paler, and characterized by harder consistency, and higher pH and cooking losses. Macroscopically, the condition affected main-ly the cranial portion of the fillet, and was defined by the presence of bulges, petechiae, fluid and clear exudate. Microscopically, muscle fibres with greater CSA were detected, as well as a higher gi-ant fibre prevalence compared to unaffected meat. A relationship between breast weight and WB condition is suggested from the data. The second study evaluated the impact of WS, alone and in combination with WB (WSWB), on the technological quality, mineral, and sensory profile of poultry meat. It emerged that the simultaneous presence of the two myopathies, with respect to the WS le-sion individually considered, had a further detrimental effect on pH, yellowness, cooking losses, in-strumental and sensory toughness. Mineral contents suggest that a defective ions regulation occurs in lesioned pectoral muscles. The third study investigated the impact of 2 coccidiosis control systems (vaccine vs anticoccidial) and 2 feeding plans (standard energy vs low energy content) on WS preva-lence and severity (level 0: no WS; level 1: moderate; level 2: severe) in chicken broiler breasts evalu-ated at 12, 25 and 51 days. All coccidiosis control systems exerted an ameliorative effect in terms of live weight, breast yield, and whole breast weight; heavier fillets were characterized by higher pH val-ues. White Striping macroscopically appeared at 25 d of age with lesions of moderate severity; at 51 days, total average prevalence was very high, with birds treated with coccidiostat showing the high-est incidences of severe lesions. Diet had no effect on overall live performance. The fourth study in-vestigated the role of myowater on WB hardness by integrating low-field nuclear magnetic reso-nance (NMR) relaxometry with texture analysis (compression test); two muscle conditions (Normal vs WB), four sampling locations (cranial-superficial, cranial-deep, medial- superficial, medial-deep) and four sampling times (10, 24, 48, 72 h p.m.) were considered. As WB affected fillets experience tis-sue degenerative changes, myowater distribution and properties were found to vary compared to the unaffected counterparts. Moreover, partial water molecules relocalisation toward extramyofibrillar spaces occurs in WB samples during storage, along with an increase in the mobility of water trapped into the myofibrillar matrix. The cranial-superficial layer of breasts exhibited the highest amount of the extramyofibrillar water, and the texture of this muscle part was harder than the deep layers of both cranial and medial portions. Therefore, a positive correlation between muscle hardness and the mobility of water trapped into the myofibrillar matrix was discovered in WB fillets, opening a new hypothesis alternative to fibrosis, to explain the characterising hard consistency of WB, even though the role of myowater on muscle hardness was not fully clarified.Due miopatie del muscolo pettorale superficiale (Pectoralis major) denominate White Striping (WS) e Wooden Breast (WB) stanno assumendo grande rilevanza per il settore avicolo da carne a causa delle ingenti perdite economiche che stanno causando. I danni sono attribuibili all’aspetto visivo e al peggioramento della qualità nutrizionale e tecnologica dei petti affetti. Nonostante ciò, la loro eziologia non è chiara e la conoscenza delle conseguenze sulla qualità delle carni affette è ancora in-completa. Pertanto, la presente tesi di Dottorato, che comprende quattro ricerche, mira ad appro-fondire le conoscenze possedute dalla comunità scientifica su questi difetti. Il primo studio ha esa-minato gli effetti della miodegenerazione del tessuto muscolare del petto di broiler ibridi affetti da Wooden Breast sulla qualità della carne e ha contribuito a tipizzare le lesioni macroscopiche ed istolo-giche. A questo scopo, i rilievi hanno riguardato il peso, l’area della sezione trasversale (CSA), il pH e il colore (L* a*, b*), la capacità di ritenzione idrica e lo sforzo di taglio. I campioni di petto inoltre sono stati anche valutati visivamente ed istologicamente. I petti affetti da Wooden Breast sono ri-sultati più pesanti, più spessi, più pallidi, più duri al tatto e hanno presentato valori di pH e perdite di cottura più alti. Macroscopicamente, la condizione ha colpito prevalentemente la parte craniale del petto; le lesioni caratterizzanti sono risultate la presenza di globosità, di petecchie, di un essuda-to fluido e chiaro sulla superficie. Microscopicamente, nel WB si sono osservate fibre muscolari con maggiore CSA, così come una maggiore prevalenza di fibre giganti rispetto ai campioni non affetti. Dai dati ottenuti, si suggerisce una relazione tra il peso del petto e la condizione WB. Il secondo studio ha valutato l'impatto del White Striping sia da solo che in combinazione con il Wooden Breast (WSWB) sulla qualità tecnologica e sui profili minerale e sensoriale dei petti di broiler ibrido. È emerso che la presenza contemporanea delle due miopatie, rispetto al solo WS, ha esercitato un ulteriore effetto peggiorativo sul pH, sull'indice del giallo, sulle perdite di cottura, sulla durezza strumentale e sensoriale. Il profilo minerale ottenuto suggerisce uno squilibrio ionico nelle fibre mu-scolari dei petti affetti. Il terzo studio ha valutato l'impatto di due metodi di controllo della cocci-diosi (vaccino vs coccidiostatico) e di due piani di alimentazione (standard vs basso contenuto di energia) sulla prevalenza e la gravità del WS (livello 0: assenza, livello 1: moderato, livello 2: grave) in petti di broiler ibridi esaminati a 12, 25 e 51 giorni di età. Entrambi i sistemi di controllo della coccidiosi hanno esercitato un effetto migliorativo su peso vivo, resa in petto e peso del petto; i pet-ti più pesanti sono stati caratterizzati da valori di pH più elevati. Il WS è comparso macroscopica-mente a 25 giorni di età con lesioni di moderata gravità; a 51 giorni la prevalenza media totale è stata molto elevata, con il gruppo trattato con coccidiostatico che ha evidenziato la maggior inci-denza di lesioni gravi. La dieta non ha avuto alcun effetto sulle prestazioni produttive. Il quarto studio ha esaminato il ruolo dell’acqua contenuta nel muscolo pettorale del broiler ibrido sullo svi-luppo della tipica durezza del WB, integrando analisi di risonanza magnetica nucleare (NMR) e test di compressione. Come fattori, sono stati considerati due condizioni muscolari (Normale vs WB), quattro punti (craniale-superficiale, craniale-profondo, mediano-superficiale, mediano-profondo) e quattro tempi di conservazione (10, 24, 48, 72 h p.m.). Poiché i petti WB esibiscono alterazioni de-generative dei tessuti, di conseguenza la distribuzione e le proprietà delle molecole d’acqua presenti nel muscolo sono risultate diverse rispetto ai petti normali. Inoltre, nel corso della conservazione post mortem, i petti Wooden Breast hanno evidenziato una parziale redistribuzione dell’acqua a fa-vore della frazione extramiofibrillare, unitamente ad una maggiore mobilità della frazione d’acqua intrappolata nella matrice miofibrillare. La porzione craniale- superficiale dei petti ha evidenziato una maggior quantità di acqua extramiofibrillare ed una consistenza più dura rispetto agli strati pro-fondi di entrambe le parti craniale e mediale del muscolo. Pertanto, è emersa nel WB una correlazio-ne positiva tra la durezza muscolare e la mobilità dell'acqua intrappolata nella matrice miofibrillare, aprendo una nuova ipotesi alternativa alla fibrosi per spiegare la caratteristica durezza del WB, anche se il ruolo dell’acqua sulla durezza muscolare non è stato ancora completamente chiarito
Sensory acceptability of rabbit meat patties manufactured with increasing levels of rooibos (Aspalathus linearis) tea extract.
No full text
How does “wooden breast” myodegeneration affect poultry meat quality?
No full textThe aim of the research was to study the
effects of “Wooden Breast” (WB) myodegeneration
on poultry meat quality. At a poultry meat cutting
facility, 30 normal (N) and 30 WB (WB) fillets
(Pectoralis major muscle) were selected to measure
the weight, cross sectional area, pH and L*a*b*
colour values at 48h post mortem, and pH, L*a*b*
colour values, water-holding capacity and Warner-
Bratzler shear force after 3 months of storage at -20
°C. Data on WB condition showed a negative effect
on all of the variables, measured at the cranial end
of fillets, where lesions were more visible
Prevalence of White Striping and Wooden Breast on broiler meat subjected coccidiosis to different control programs
No full textWhite Striping (WS) and Wooden Breast (WB) are alterations of broiler meat characterised by white striation parallel to the direction of muscle fibres, and paleness and harness of the meat, respectively. In this study the effects of coccidiosis control system and low energy diet on WS and WB prevalence were evaluated.
One day-old chicks (Ross 708) were randomly divided in 4 groups of 140 each and assigned to 4 treatments: Control (C), Coccidiostat (Cox), Vaccinated (V), and Vaccinated fed with a Low Energy diet (VLE). Birds were slaughtered at 51 days of age and breasts were scored for both WS and WB based on the severity of condition as: 0= normal, 1= moderate, 2= severe.
No body weight (BW) and average daily gain (ADG) differences were observed between Cox (BW 3.7±0.3 kg ADG 71.1±5.5 g/day), V (BW 3.6±0.4 kg ADG 69.6±6.9 g/day) and VLE (BW 3.7±0.3 kg ADG 71.2±6.3 g/day) groups, being the difference C (BW 3.5±0.3 kg ADG 67.6±5.8 g/day) vs Cox and VLE significant (P<0.05).
The total WS prevalence was above 90% and no differences were observed among groups. The prevalence of WS score 2, covariated by the BW, showed a difference (P<0.01) between Cox (77.6%) and C (61.6%), V (62.6%), VLE (64.4%). The WB prevalence was 64% (C), 51.3% (Cox), 53.4% (V), 55.7% (VLE), and no differences were observed among groups.
The use of vaccine resulted in a reduction of WS grade 2 but had no effect on WB. Diet had no effect on WS and WB prevalence
Supplementing growing rabbit diets with chestnut hydrolyzable tannins: Effect on meat quality and oxidative status, nutrient digestibilities, and content of tannin metabolites
No full textBlack soldier fly as dietary protein source for broiler quails: meat proximate composition, fatty acid and amino acid profile, oxidative status and sensory traits
Full text linkImpact of coccidiosis control program and feeding plan on white striping prevalence and severity degree on broiler breast fillets evaluated at three growing ages
Full text linkWHITE STRIPING APPEARANCE ALONG GROWTH ON BROILER CHICKENS TREATED WITH DIFFERENT COCCIDIOSIS CONTROL PROGRAMS
No full textWhite striping (WS) is an alteration of broiler muscle characterised by the presence of white striations parallel to the direction of muscle fibers. This condition is becoming increasingly important in broiler production because it affects the acceptance of raw meat by the consumer and its hysicochemical characteristics, thus decreasing the economic value (1). In this study the age of WS onset in broiler chickens and the effect of diet and of different coccidiosis control programs on WS prevalence at slaughter, were evaluated.
Four groups of 180 chickens were randomly allotted to four experimental treatments: control (C), coccidiostat (Cox), vaccinated (V), and vaccinated fed with a low energy diet (VLE). The birds were weighed at 12, 25, 42, and 51 d of age. Twenty animals per treatment were sacrificed at 12 and 25 d of age, whereas the remaining chickens at 51 d. Breasts were categorized based on the degree of WS following the lesion score proposed by Kuttappan et al. (2): 0=absence (normal breast), 1=moderate (breast with white lines less than 1 mm thick), 2=severe (breast with white lines more than 1 mm thick). For histological evaluation, up to now 34/80 (d 12) and 46/80 (d 25) breast samples were examined.
At 12 d of age all breasts were classified as normal (WS score 0), whereas at 25 d of age WS was macroscopically evident with score 1 in a limited number of birds (3/20 group C, 2/20 group Cox, 3/20 group V, 1/20 group VLE).
Histologically, myopathic changes were found in 29/34 (85%) of samples at d 12, and 46/46 (100%) of samples at d 25. At d 12, breast muscles were affected by fiber size change, and multifocal mild degeneration/necrosis, while at d 25 these alterations were increasingly severe and associated with heterophilic and macrophagic infiltration, early interstitial fibrosis, and fat infiltration.
The absence of macroscopic lesions at d 12 associated with the presence of early and mild histological lesions in some samples indicates the onset of WS around 12 d.
At 51 d of age the prevalence of WS was above 90% in all groups, and the prevalence of WS score 2 was 77.6%, 64.4%, 62.6% and 61.6%, for Cox, VLE, V and C, respectively, being significant (P<0.001) the difference Cox vs V and C.
The coccidiostat effect on the increase in WS severity seems attributed to the higher initial birds’ growth.
This study provided a new perspective for the control of WS prevalence and a starting point for further studies.
REFERENCES
1. Kuttappan, V. A., V. B. Brewer, P. W. Waldroup, and C. M. Owens. 2012. Influence of growth rate on the occurrence of white striping in broiler breast fillets. Poult. Sci. 91:2677–2685.
2. Kuttappan, V. A., H. L. Shivaprasad, D. P. Shaw, B. A. Valentine, B. M. Hargis, F. D. Clark, S. R. McKee and C. M. Owens. 2013. Pathological changes associated with white striping in broiler breast muscles. Poult. Sci. 92:331-338
Technological quality, mineral profile and sensory attributes of broiler chicken breasts affected by White Striping and Wooden Breast myopathies
Full text linkThe aim of the research was to study the impact of white striping and wooden breast myopathies on the technological quality, mineral, and sensory profile of poultry meat. With this purpose, a total of 138 breasts were selected for a control group with normal breasts (N), a group of breasts characterised by white striping (WS) myopathy, and a group of breasts having both white striping and wooden breast myopathies (WSWB). Data revealed that the simultaneous presence of the two myopathies, with respect to the WS lesion individually considered, had a further detrimental effect on pH (6.04 vs. 5.96; P < 0.05), yellowness (11.4 vs. 10.3; P < 0.01), cooking losses (30.4 vs. 27.6%; P < 0.05), toughness instrumental values (22.8 vs. 20.0 N; P < 0.01), and perception (6.22 vs. 5.56; P < 0.01). In addition, mineral contents suggest that a defective ions regulation is also present in white striping and wooden breast myopathies
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