Effects of trace minerals source in the broiler breeder diet and eggshell translucency on embryonic development of the offspring

In 2 experiments, interactions between trace mineral (Zn, Mn, Cu, Se) source (organic or inorganic) in the broiler breeder diet and egg translucency (high or low) on egg characteristics and embryonic development were investigated. In the first experiment, eggs from old breeders (55-57 wk) and in the second experiment, eggs from prime breeders (34-36 wk) were used. Egg composition and bacterial load on the eggshell were analyzed in fresh eggs. During incubation, metabolic heat production of the embryos (d 8 (E8) to 19 of incubation) and tibia ossification (E8.5-E14.5) were determined daily. At hatch, chicken quality was assessed, including tibia biophysical characteristic. Egg quality was not affected by breeder trace minerals source or egg translucency in both experiments. In both experiments, an interaction between trace minerals source and translucency score was found for egg weight loss during incubation. In inorganic trace minerals fed breeders, a high egg translucency resulted in a higher egg weight loss than a low egg translucency, whereas this difference was not seen in organic trace minerals fed breeders. Embryonic heat production and tibia ossification were not affected by trace minerals source or egg translucency. Chicken quality showed ambiguous results between experiment 1 and 2 regarding trace minerals source in the breeder diet. In experiment 2, high translucent eggs from organic fed breeders hatched later than eggs from the other three treatment groups and additionally, high egg translucency resulted in lower residual yolk weight and higher heart and liver percentage of YFBM compared to low egg translucency. Tibia biophysical characteristics at hatch were not affected by trace minerals source or egg translucency. It can be concluded that organic trace minerals source in broiler breeder diet affects eggshell conductance, particularly in low translucent eggs, but effects on chicken quality and tibia characteristics appears to be limited.

Quercetin ameliorates chicken quality by activating the PI3K/PKB/AMPK signaling pathway in broilers

This study was conducted to investigate the effects and mechanism of quercetin on chicken quality in broilers. We selected 480 AA broilers (1 day old) and randomly allotted those to four treatments (negative control and 0.2, 0.4, or 0.6 g of quercetin per kg of diet) for 42 days. Compared with the control group, the supplementation with 0.4 g of quercetin significantly increased the pH_45min and L ^* value of the thigh muscle and decreased the shearing force of the thigh muscle and breast muscle and drip loss of the thigh muscle (P < 0.05). The supplementation with 0.6 g/kg of quercetin significantly increased the pH_45min and L ^* value of the thigh muscle, and pH_45min of breast muscle and decreased the drip loss of the thigh muscle (P < 0.05). Sensory scores of meat color, tenderness, and juiciness also were improved with increasing quercetin concentration (P < 0.05). The inosinic acid (IMP) content of the breast and thigh muscles of broilers was significantly increased by supplementation with 0.6 g/kg of quercetin (P < 0.05). Supplementation with 0.2, 0.4, and 0.6 g of quercetin significantly reduced mRNA expression of L-FABP (P < 0.05, P < 0.05, and P < 0.05); supplementation with 0.4 and 0.6 g/kg of quercetin significantly increased mRNA expression of PKB and AMPKα1 (P < 0.05 and P < 0.05); supplementation with 0.6 g/kg of quercetin in the diet significantly reduced mRNA expression of SREBP1 and HMGR (P < 0.05 and P < 0.05) and significantly increased mRNA expression of CPT1 and PPARγ (P < 0.05 and P < 0.05); and supplementation with 0.2, 0.4, and 0.6 g/kg of quercetin significantly increased mRNA expression of PI3K, LPL, and Apo A1 and significantly reduced mRNA expression of ACC and FATP1 in the breast muscle of broilers (P > 0.05). PI3k, PKB, AMPK, SREBP1, and L-FABP were significantly and positively correlated with pH_45min (P < 0.05); PPARγ was significantly and positively correlated with shear force (P < 0.05); CPT1 was significantly and positively correlated with the L ^* value (P < 0.05); and HMGR was significantly and positively correlated with drip loss (P < 0.05). In conclusion, quercetin improved the meat quality, protecting it against lipid oxidation and deposition by regulating the PI3K/PKB/AMPK_α1 signaling pathway in the breast muscle of broilers.

Interactions between egg storage duration and broiler breeder age on egg fat content, chicken organ weights, and growth performance

Egg storage and breeder age are between the most important factors affecting egg lipids, chicken quality, and posthatch performance. To evaluate these factors, including their interaction, the impact of egg storage duration (5, 12, and 19 D), and breeder age (47 and 67 wk) was investigated in Arbor Acres broiler eggs and chickens. Total yolk fat content, chicken organ development at hatch and at 6 D of age, and posthatch performance (at 7 D and 35 D of age) were determined. Total fat content in fresh yolk was lower in 12 and 19 D stored eggs than in 5 D stored eggs (Δ = −2.42% on average). In hatchlings, the heart percentage was not affected by storage duration in the younger flock but was higher after 19 D than after 5 and 12 D of storage in the old flock (Δ = +0.09% on average). Residual yolk weight was higher after 12 D egg storage than after 5 D egg storage (Δ = +1.7 g), with 19 D egg storage in between. Liver and intestine percentage decreased with storage duration. Residual yolk weight (Δ = +1.09 g) and liver percentage (Δ = +0.18%) were higher in old breeders than in younger breeders. At day 6, chicken BW, yolk free body mass, liver percentage, and intestine percentage interacted between egg storage duration and breeder age with the strongest effects in chickens from older breeder after 19 D of storage. Heart percentage was lower after 19 D compared with 5 and 12 D of storage (Δ = −0.05% on average). Feed intake and feed conversion ratio were higher between day 0 to 7 and 0 to 35 after 19 D than after 5 D egg storage (Δ19-5 D = +12 g and +199 g; +0.11 points and +0.09 points, respectively). It can be concluded that when it is needed, eggs from younger breeders should be stored for a prolonged period (≥12 D) rather than those from older breeders.

Wooden-Breast, White Striping, and Spaghetti Meat: Causes, Consequences and Consumer Perception of Emerging Broiler Meat Abnormalities

Ten years ago, the occurrence of macroscopic defects in breasts muscles from fast-growing broilers challenged producers and animal scientists to label and characterize myopathies wholly unknown. The distinctive white striations in breasts affected by white striping disorder, the presence of out-bulging and pale areas of hardened consistency in the so-called wooden breast, and the separation of the fiber bundles in breasts labelled as spaghetti meat, made these myopathies easily identified in chicken carcasses. Yet, the high incidence of these myopathies and the increasing concern by producers and retailers led to an unprecedented flood of questions on the causes and consequences of these abnormal chicken breasts. This review comprehensively collects the most relevant information from studies aimed to understand the pathological mechanisms of these myopathies, their physicochemical and histological characterization and their impact on meat quality and consumer's preferences. Today, it is known that the occurrence is linked to fast-growth rates of the birds and their large breast muscles. The muscle hypertrophy along with an unbalanced growth of supportive connective tissue leads to a compromised blood supply and hypoxia. The occurrence of oxidative stress and mitochondrial dysfunction leads to lipidosis, fibrosis, and overall myodegeneration. Along with the altered appearance, breast muscles affected by the myopathies display poor technological properties, impaired texture properties, and reduced nutritional value. As consumer's awareness on the occurrence of these abnormalities and the concerns on animal welfare arise, efforts are made to inhibit the onset of the myopathies or alleviate the severity of the symptoms. The lack of fully effective dietary strategies leads scientists to propose whether "slow" production systems may alternatively provide with poultry meat free of these myopathies.