1. Expression of myostatin is not altered in lines of poultry exhibiting myofiber hyper- and hypoplasia;Mott;Poult. Sci.,2002
2. Reproductive complications associated with selection for broiler growth;Siegel;Br. Poult. Sci.,1985
3. Statistical analysis: The experimental unit for egg trait analysis was each egg (60 replicates per strain). During incubation the experimental unit was each group of 30 eggs per strain, providing 22 replicates at the start of experimentation. Replicates were randomized with respect to strain and location within the incubator. Prior to hatch, plastic dividers were used to separate each incubator tray into 3 smaller sections, ensuring that 30 eggs from each strain were represented in every tray. Since some strains were mixed because the dividers were too pliable, the number of replicates was reduced. The unaffected trays provided 8 replicates of 30 eggs per strain for analysis and were the basis for subsequent results. For the carcass characteristic data at hatch (Table 3), the experimental unit was each of 10 chicks per strain and sex. During the rearing portion of the trial, the experimental unit was each cage having 10 birds per strain and sex (8 replicate cages per strain). The data (excluding egg characterization analysis) were analyzed using the general linear model procedure in SAS [4]. To separate differences attributed to the egg vs. those of the dam, egg trait data were analyzed with egg weight as the covariate using the general linear model procedure in SAS [4]. Hatch data were transformed to arc sine values before analysis. Differences between treatment means were separated using the Tukey's honestly significant difference test. Significance was based on testing at P = 0.05. Means are shown with ± SEM. Among strains, differences between males and females were not found and, therefore, will not be discussed further.
4. The SAS System for Windows, Release 8.02;SAS Institute,2001
5. Personal communication;Emmerson,2004