Evaluation of the Use of Phosphatidic Acid in the Diet on Growth Performance and Breast Meat Yield in Broilers

Evaluation of the Timing of Use of Phosphatidic Acid in the Diet on Growth Performance and Breast Meat Yield in Broilers

With a growing increase in further processing of poultry, there has been an increased interest in factors, including feed additives, that may improve broiler performance, increase growth, and influence dressing percentage. Mammalian target of rapamycin (mTOR) is known to play vital roles in protein synthesis; mTOR controls the anabolic and catabolic signaling of skeletal muscle mass, resulting in the modulation of muscle hypertrophy. Exogenous phosphatidic acid (PA) can stimulate the mTOR pathway via its activation of the substrate S6 kinase. A study with 648 Cobb 500 male broilers, housed in 36 floor pens (1.11 m2) from 1 to 42 days of age was conducted to evaluate the timing of PA (Mediator® 50P, Chemi Nutra, Austin, TX, USA) supplementation on the growth performance and carcass yield of broilers. Dietary treatments included T1, Control (CON), T2, 5 mg/bird/day of PA for 42 days (d0−42, PAA); T3, 5 mg/bird/day of PA for 28 days (d15−42, PAGF); and T4, 5 mg/bird/day of PA for 14 days (d29−42, PAF). All birds were weighed on d14, 28, and 42 to obtain BW (body weight), FCR (feed conversion ratio), and MORT (mortality percentage). On d42, eight birds per pen were processed to determine carcass and breast meat yield. No differences were observed in BW at d14 or d28. At d42, birds fed PAA were heavier (3.73 ± 0.02, p < 0.05) than all dietary treatments (3.68 ± 0.02). From d0 to d28, birds fed PAA had the lowest FCR (1.423 ± 0.005, p < 0.05) compared to all dietary treatments (1.441 ± 0.005). From d0 to d42, birds fed PAA and PAGF had a lower FCR (1.545 ± 0.014, p < 0.05) when compared to the CON (1.609 ± 0.013). No differences were observed in MORT between treatments during growout. Increased BW observed in birds fed PAA translated to increased breast fillet weight (0.772 ± 0.009 kg, p < 0.05) when compared to the CON (0.743 ± 0.008 kg). Carcass yields were increased in birds fed PAA (77.48 ± 0.32 kg, p < 0.05) when compared to all dietary treatments (76.24 ± 0.16 kg). Utilizing PA for 42 days increased live weights, improved FCR, increased carcass yield, and increased breast fillet weight at processing. Results from this study indicate that supplementation of PA during all phases of growth may increase the production efficiency of broilers.

Relationship among Sex, Skin Color, and Production Parameters of Broiler in Pectoral Myopathies

Breast anomalies in broilers, especially wooden breast (WB) and spaghetti meat (SM), cause high economic losses to the poultry meat sector. In order to identify the parameters that have a causal effect and to reduce the incidence of these myopathies, 141,792 broilers were analyzed in a total of 1477 batches using a visual grading system. The relationship among productive parameters such as the feed conversion ratio, live weight, growth rate, and mortality, was evaluated. Effects due to skin color (white vs. yellow), broiler sex (male, female, and mixed groups), feed presentation (grain vs. mash), and veterinary treatments (treated vs. untreated) were also included in the statistical study. Live weight was observed to have a significant effect (p < 0.001) on WB incidence, which increased by 1.11 for each 100 g of weight. Weight did not significantly affect the incidence of SM. Males had a higher incidence of WB and a lower incidence of SM than females. The incidence of both myopathies varied between samples that turned out to be significantly affected by some of the variables considered in the model, such as grain feeding and the feed conversion ratio. Controlling these factors in the broiler production could help to reduce the incidence of WB and SM.

Energy metabolism and sources of oxidative stress in wooden breast - a review

Modern broilers show dramatic growth over a short interval and contribute directly to the success of the poultry meat industry. The growth performance of commercial broilers is a result of genetic selection for "performance traits", such as body size, meat yield, and feed conversion rate. However, due to the rapid growth rate of modern commercial broilers, several growth-related conditions have arisen, increasing economic losses and consumer concerns. Among the most economically consequential is the muscle disorder called wooden breast. Together with associated myopathies such as white striping and spaghetti meat, wooden breast is causing losses of $200 million a year in the U.S. alone and occurs worldwide. No causative factors are known for wooden breast to date. Wooden breast can affect over 80% of broilers in a flock, yet no methods of amelioration are currently available. Overall, the evidence suggests that wooden breast is a genetic, age-dependent condition associated with fast growth rate. The primary features of wooden breast are muscle degeneration and fibrosis, high levels of oxidative stress, hypoxia, and altered energy metabolism. Recent work has also implicated reduced pectoral vessel density in the pathogenesis of wooden breast. This review examines the history of myopathies in commercial broilers and the relationship of myopathies to metabolism and oxidative performance. This review summarizes the foundational knowledge of wooden breast and provides a platform for further investigation of wooden breast.