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This is the first report providing estimates of the genetic basis of breast muscle myopathies (BMM) and their relationship with growth and yield in broiler chickens. In addition, this paper addresses the hypothesis that genetic selection for increase breast yield has contributed to the onset of BMM. Data were analyzed from ongoing recording of BMM within the Aviagen breeding program. This study focused on three BMM: deep pectoral myopathy (DPM; binary trait), white striping (WS; 4 categories) and wooden breast (WB; 3 categories). Data from two purebred commercial broiler lines (A and B) were utilized providing greater than 40,000 meat quality records per line. The difference in selection history between these two lines has resulted in contrasting breast yield (BY): 29% for Line A and 21% for Line B. Data were analyzed to estimate genetic parameters using a multivariate animal model including six traits: body weight (BW), processing body weight (PW), BY, DPM, WB, and WS, in addition to the appropriate fixed effects and permanent environmental effect of the dam. Results indicate similar patterns of heritability and genetic correlations for the two lines. Heritabilities (h²) of BW, PW and BY ranged from 0.271-0.418; for DPM and WB h² <0.1; and for WS h² ≤0.338. Genetic correlations between the BMM and BW, PW, or BY were ≤0.132 in Line A and ≤0.248 in Line B. This paper demonstrates the polygenic nature of these traits and the low genetic relationships with BW, PW, and BY, which facilitates genetic improvement across all traits in a balanced breeding program. It also highlights the importance of understanding the environmental and/or management factors that contribute greater than 65% of the variance in the incidence of white striping of breast muscle and more than 90% of the variance of the incidence of wooden breast and deep pectoral myopathy in broiler chickens. [ABSTRACT FROM AUTHOR]

This paper aimed to study the dietary effects of Bacillus subtilis fmbj (BS fmbj) on growth performance, small intestinal histomorphology, and its antioxidant capacity of broilers at 21 d of raising. A total of 300 1-d old male Arbor Acres broilers were randomly assigned to 5 groups: broilers fed the basal diets with 0 g/kg BS fmbj (CON), 0.2 g/kg BS fmbj (BS-1), 0.3 g/kg BS fmbj (BS-2), 0.4 g/kg BS fmbj (BS-3), and 0.5 g/kg BS fmbj (BS-4). The results showed that there were no differences in the growth performance among treatments during the trail. Dietary BS fmbj in broiler diets increased (P < 0.05) the serum immunoglobulin A (IgA) and immunoglobulin G (IgG) concentration, and enhanced the secretory immunoglobulin A (sIgA) level of small intestine (jejunum and ileum) compared with those in the CON group. The BS groups could improve (P < 0.05) the values of villus length, villus width, crypt depth, and villus area of small intestine compared with that in the CON group. Compared with the CON group, the BS group increased (P < 0.05) small intestinal antioxidant capacity and its mitochondrial antioxidant capacity, and also improved the antioxidant related-gene expression. The BS group exerted a lower (P < 0.05) level of oxidative damages in small intestine than that of the CON group. In conclusion, dietary BS fmbj in broiler diets was potential to improve the small intestinal histomorphology, small intestinal antioxidant capacity, and its mitochondrial antioxidant capacity. Thus this BS fmbj might be considered to be an important additive for the poultry industry. [ABSTRACT FROM AUTHOR]

There has been much recent interest in mathematical developments for the analysis of growth in poultry. In this paper, we present a sinusoidal function to describe the evolution of growth as a function of time based on real life experiments. The function was evaluated with regard to its ability to describe the relationship between body weight and age in broilers and was compared to 4 standard growth functions: Gompertz, logistic, Lopez, and Richards. In order to estimate the model parameters, we adopted a global optimization method based on a direct search method instead of using gradient-based techniques. The results of this study show that both the sinusoidal function and the direct search method precisely describe the growth dynamics of broiler chickens. Fitting the growth functions to different data profiles nearly always led to the same or less maximized log-likelihood values for the sinusoidal equation, which is an indication of its superiority in describing growth data from broiler chickens. [ABSTRACT FROM AUTHOR]

The existing literature is inconsistent with respect to optimal dietary concentrations of glycine (Gly) and serine (Ser) in broiler feed. Therefore, we conducted a meta-analysis to investigate the response of broilers to dietary levels of Gly using a full quadratic model based on mixed model methodology. Response was measured as ADG (g/d), ADFI (g/d), and G:F (g/g). In addition, the influence of other dietary constituents was evaluated. This meta-analysis was based on a data set comprising a total of 9,626 broilers in 10 peer-reviewed papers that investigated the response of broilers to different dietary concentrations of Gly, achieved by addition of free Gly. The fitted quadratic model, with either Gly+Ser or the calculated glycine equivalent (Glyequi) of both amino acids as the independent variable, revealed that all model terms were significant (P ≤ 0.05), and hence proved a curvilinear relationship between these independent variables and response traits. The R² value and root MS error confirmed a strong relationship between observed and predicted traits. A comparison of the influence of Gly+Ser and Glyequi on response traits revealed that both approaches produced similar results. Because Glyequi should meet the physiological values of a diet better than Gly+Ser, models with 2 independent variables were conducted using Glyequi. The second independent variables were methionine (Met):TSAA ratio and the concentrations of cysteine (Cys) and CP. In models with one or 2 independent variables, the impact of dietary Gly on ADFI was low. By contrast, G:F was markedly influenced by dietary Gly; this effect intensified at lower Met:TSAA ratios and higher Cys and CP levels. ADG was also a function of Glyequi and the second independent variables. For ADG, an optimal Met:TSAA ratio of 0.655 and Cys concentration of 0.302% was calculated. Following the nonlinear nature of relationship, generally applicable replacement values could not be calculated. However, it was concluded that consideration of dietary Cys can diminish the requirement for Glyequi, and therefore, enable a reduction in the CP of broiler diets without limiting growth performance. [ABSTRACT FROM AUTHOR]

An abstract of the paper "Expression of Pro-Inflammatory Cytokines in Lungs of Ascites-Resistant and -Susceptible Broiler Chickens Following Intravenous Cellulose Microparticle Injection," by K. R. Hamal and colleagues is presented.

An abstract of the paper "Assessment of Closiridium perfringens and Clostridium septicum from commercial broilers with gangrenous dermatitis and asymptomatic broilers within the same houses," by S. Dunham and colleagues is presented.

The article presents an abstract of the research paper "Comparison of digestible lysine needs in the starter period when fed diets formulated to ideal ratios or added alone," by F.G.P. Costa and colleagues.

The article presents an abstract of the research paper "Assessment of the interassay repeatability of ileal amino acid digestibility in wheat fed to broilers," by A. Bandegan and colleagues.

The article presents an abstract of the research paper "Additive effects between ingredients on ileal amino acid digestibility in broilers," by V. Ravindran and colleagues.

The article presents an abstract of the research paper "Administration of mushroom extract to broiler chickens for bifidobacteria enhancement in the gut and feces," by W.L. Willis.

The article presents an abstract of the research paper "Evaluation of XPC™ and prototypes on aflatoxin challenged broilers," by G.D. Osweiler and colleagues.

An abstract of the paper " The effect of egg storage period and turning frequency during incubation on fertile hatchability, hatchling organ weights, and broiler performance," by N. Okur and colleagues is presented.

An abstract of the paper "Organic trace minerals (Mintrex&x00AE; P) in broiler breeder diets and pre-incubation conditions on bone development and leg health of broilers," by E.O. Oviedp-Rondon and colleagues is presented.

An abstract of the paper "Performance of Broilers Fed Commercial Forms of Phytases With Different Biochemical Characteristics: P. Lycii, A. Niger and E. Coli," by P. W. Waldroup and colleagues is presented.

The article presents an abstract of the research paper "Case report: Necropsy findings during a phytase research trial in broilers," by T.O. Conner-Dennie and colleagues.

The article presents an abstract of the research paper "The effect of dietary protein level and digestibility and Clostridium perfringens infection on the growth performance of broiler chickens," by G.P. Widyaratne and colleagues.

The article presents an abstract of the research paper "Phase feeding in a small-bird production scenario: Impact on growth and uniformity," by V.B. Brewer and colleagues.

The article presents an abstract of the research paper "Performance, organ morphology, and abdominal fat of broilers supplemented with a probiotic and garlic as an alternative to antibiotic growth promoters," by H. Collazos and colleagues.

The article presents an abstract of the research paper "Broiler performance on a COBAN® anticoccidal program with exposure to a mixed Eimeria population," by R.C. Van Wyhe and colleagues.

The article presents an abstract of the research paper "Efficacy of a novel, clostridial probiotic (Clostridium butyricum MIYAIRI 588) in broilers," by M.I. Gracia and colleagues.

The article presents an abstract of the research paper "Effect of a lactobacilli feed additive supplementation on performance of broilers," by M.I. Gracia and colleagues.

The article presents an abstract of the research paper "Medicinal plants (Marjoram, Sweet Basil and/or Rosemary) supplementation to broiler diets as feed additives: Effects on performance, carcass traits, immunity and economics," by H.M. Yackout and colleagues.

The article presents an abstract of the research paper "Changes of biochemical parameters and enzymes activities in broiler chickens with cold induced ascites," by A.G. Golian and colleagues.

The article presents an abstract of the research paper "Effects of Graded Levels of Melamine in Young Broiler Chicks," by D.R. Ledoux and colleagues.

The article presents an abstract of the research paper "Enzyme complex containing NSP-enzymes and phytase improves the performance of broilers fed corn-based diet," by M. Francesch and P.A. Geraert.