Growth, carcass composition and meat quality response to dietary concentrations in fast-, medium- and slow-growing commercial broilers

Abstract

-Growth, carcass composition and certain meat quality traits were studied in fast (F), medium (M) and slow (S) growing broilers fed with 3 regimes appropriate for each chicken type and differing on average by 418 kJ·kg -1 AMEn and 1% crude protein (P1 > P2 > P3). No significant interactions between chicken types and feed were measured before 3 weeks and after 6 weeks of age, indicating that the 3 genotypes had similar responses to the 3 diets during these periods. Before 3 weeks of age, body weight was 5% higher for P1 compared to P2 and P2 compared to P3 fed chickens for a comparable feed intake. After 6 weeks of age, a 10% reduction in feed intake occurred in P3 compared to P1 and P1 compared to P2 fed chickens for similar body weight gains. The differing responses after 6 weeks of age might be linked to high heat stress that occurred at 7 weeks of age. Between 3 and 6 weeks of age, interactions between chicken type and dietary concentration on feed intake, body weight gain characterised an "after 6 weeks of age" response for F-chickens whereas Mand S-chickens had a "before 3 weeks of age" response. These interactions might be explained by a higher sensitivity of fast-growing chickens to environmental conditions. For chickens slaughtered at market age (F = 6, M = 8 and S = 12 weeks of age), higher breast meat yield (Pectoralis major + minor) and lower abdominal fat content were observed in the F-chickens (17.2% and 2.64%, respectively) compared to the M-(15.7% and 2.86%, respectively) and S-chickens (14.4% and 3.44%, respectively; P < 0.05). Breast meat was more coloured in the S-chickens with lower L* and higher b* and a* 72 hours after slaughter than in the M-and F-chickens (P < 0.05). Dietary concentration had no significant effect on carcass composition, ultimate pH or drip loss of breast meat. Our results suggest that changes in dietary concentration alter growth performance but have little effect on carcass composition and meat quality traits. Résumé -Effet de la concentration de l'aliment sur la croissance, la composition de la carcasse et la qualité de la viande de poulets de chair à croissance rapide, moyenne ou lente. La croissance, la composition de la carcasse et quelques paramètres de qualité de la viande ont été étudiés chez des poulets à croissance rapide (F), moyenne (M) et lente (S) alimentés par 3 régimes de concentration énergétique et protéique croissante (+ 418 kJ·kg -1 EMAn et + 1 % de protéine brute, P1 > P2 > P3). Aucune interaction significative entre le génotype et l'aliment n'a été mesurée avant 3 semaines et après 6 semaines d'âge indiquant que les 3 types de poulets ont des réponses semblables aux 3 régi-mes. Avant 3 semaines d'âge, le poids vif est augmenté de 5 % avec P1 comparé à P2 et avec P2 comparé à P3 pour une consommation semblable des 3 aliments. Après 6 semaines d'âge, une réduction de 10 % de la consommation est observée entre les aliments P1 par rapport à P2 et P2 par rapport à P3 pour un gain de poids semblable avec les 3 aliments. Ces différentes réponses pe...

Proximate composition and meat quality of broilers reared under different production systems

“…These conditions possibly influenced the uniformity of the pH values found among the treatments in the present study. Literature reports results that are consistent with the findings of the present study (Lonergan et al, 2003;Quentin et al, 2003 andSantos et al, 2005).…”

“…Genetic factors possibly have higher influence on color parameters than pH in Paraíso Pedrês meat. The effect of genotype on color parameters was reported by several authors, including Berri et al (2005), Castellini et al (2002b), Grashorn & Clostermann (2002), and Quentin et al (2003). When tissues (breast and thighs) were compared as to redness (a*), it was found that Cobb ® birds presented higher a* values in the breast as compared to the free-range strains (Table 2).…”

Carcass morphology and meat quality from roosters slaughtered at eight months affected by genotype and finishing feeding

“…Thus, the most appreciate parts are breast and drumstick, and their percentages over total carcass are good markers of the animal economic value. The value of 15.07% for breast found in Mos roosters remained in the same order than values found by Quentin et al (2003) for a commercial French 'label' type and by Berry et al (2001) for a genetically selected broiler strain. Similar results were observed by Jaturashita et al (2008), for an indigenous Thai breed, who reported values around 15.5% for breast yield.…”

Effect of Dietary Lysine Regimens on Growth Performance and Meat Composition in Aseel Chicken

“…It was reported that meat type birds performed better with increasing amino acids densities (Zhai et al 2013(Zhai et al , 2014. Panda et al (2011) fed broiler 1.3% Lys with a specific ratio to other amino acid and, observed better results, indicating that concentrated diets can improve F:G in broiler (Quentin et al 2003). Moreover, improved F:G in high and medium Lys groups may be attributed to the higher WG and lower FI in the same groups.…”

“…Dietary Lys is important for maintenance and skeletal muscle accretion (Dozier et al 2007;Ayasan & Okan, 2010). Supplementation of Lys during early growth stages (Ayasan & Okan, 2006;Campestrini et al 2010) is beneficial because it involves the regulation of the protein synthesis and increases muscle growth (Eits et al 2003), improve weight gain and feed efficiency (Quentin et al 2003;Si et al 2004). Chickens grow faster at a relatively high dietary Lys concentration in the diet compared with diet deficient in Lys (Li et al 2013).…”