BackgroundBovine respiratory disease complex (BRDC) is an infectious disease of cattle that is caused by a combination of viral and/or bacterial pathogens. Selection for cattle with reduced susceptibility to respiratory disease would provide a permanent tool for reducing the prevalence of BRDC. The objective of this study was to identify BRDC susceptibility loci in pre-weaned Holstein calves as a prerequisite to using genetic improvement as a tool for decreasing the prevalence of BRDC. High density SNP genotyping with the Illumina BovineHD BeadChip was conducted on 1257 male and 757 female Holstein calves from California (CA), and 767 calves identified as female from New Mexico (NM). Of these, 1382 were classified as BRDC cases, and 1396 were classified as controls, with all phenotypes assigned using the McGuirk health scoring system. During the acquisition of blood for DNA isolation, two deep pharyngeal and one mid-nasal diagnostic swab were obtained from each calf for the identification of bacterial and viral pathogens. Genome-wide association analyses were conducted using four analytical approaches (EIGENSTRAT, EMMAX-GRM, GBLUP and FvR). The most strongly associated SNPs from each individual analysis were ranked and evaluated for concordance. The heritability of susceptibility to BRDC in pre-weaned Holstein calves was estimated.ResultsThe four statistical approaches produced highly concordant results for 373 top ranked SNPs that defined 126 chromosomal regions for the CA population. Similarly, in NM, 370 SNPs defined 138 genomic regions that were identified by all four approaches. When the two populations were combined (i.e., CA + NM) and analyzed, 324 SNPs defined 116 genomic regions that were associated with BRDC across all analytical methods. Heritability estimates for BRDC were 21% for both CA and NM as individual populations, but declined to 13% when the populations were combined.ConclusionsFour analytical approaches utilizing both single and multi-marker association methods revealed common genomic regions associated with BRDC susceptibility that can be further characterized and used for genomic selection. Moderate heritability estimates were observed for BRDC susceptibility in pre-weaned Holstein calves, thereby supporting the application of genomic selection to reduce the prevalence of BRDC in U.S. Holsteins.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2164-15-1164) contains supplementary material, which is available to authorized users.

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This paper describes U-shaped development in graphic symbolization and questions the cultural mediation of the evaluation and universality of the phenomenon. The U was confirmed by a comparison across selected aesthetic dimensions of 420 drawings of American children of various ages and nonartist and artist adults. Drawing scores of adult artists were only not significantly different from those of the youngest children and artist adolescents (p < 0.05, Scheffé method). A developmental sequence was uncovered in the acquisition of the ability to construct the referential connection underlying visual metaphor. Questions regarding the cultural relativity of both the occurrence and determination of the phenomenon address issues of the cognitive approach, schooling, and movements in art.

Extended laboratory culture and antimicrobial susceptibility testing timelines hinder rapid species identification and susceptibility profiling of bacterial pathogens associated with bovine respiratory disease, the most prevalent cause of cattle mortality in the United States. Whole-genome sequencing offers a culture-independent alternative to current bacterial identification methods, but requires a library of bacterial reference genomes for comparison. To contribute new bacterial genome assemblies and evaluate genetic diversity and variation in antimicrobial resistance genotypes, whole-genome sequencing was performed on bovine respiratory disease–associated bacterial isolates (Histophilus somni, Mycoplasma bovis, Mannheimia haemolytica, and Pasteurella multocida) from dairy and beef cattle. One hundred genomically distinct assemblies were added to the NCBI database, doubling the available genomic sequences for these four species. Computer-based methods identified 11 predicted antimicrobial resistance genes in three species, with none being detected in M. bovis. While computer-based analysis can identify antibiotic resistance genes within whole-genome sequences (genotype), it may not predict the actual antimicrobial resistance observed in a living organism (phenotype). Antimicrobial susceptibility testing on 64 H. somni, M. haemolytica, and P. multocida isolates had an overall concordance rate between genotype and phenotypic resistance to the associated class of antimicrobials of 72.7% (P < 0.001), showing substantial discordance. Concordance rates varied greatly among different antimicrobial, antibiotic resistance gene, and bacterial species combinations. This suggests that antimicrobial susceptibility phenotypes are needed to complement genomically predicted antibiotic resistance gene genotypes to better understand how the presence of antibiotic resistance genes within a given bacterial species could potentially impact optimal bovine respiratory disease treatment and morbidity/mortality outcomes.

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Portraiture in art is a process of representation through which the artist recreates the subject of the image, interpreting nuances of physicality and personality through artistic elements such as line, color, and composition. This artistic process results in a tangible imprint of the artist's understanding of and relationship with the subject of the portrait. Similarly, the research portrait, a written narrative, is imprinted with the researcher's understanding of and relationship with the individual or site that is represented in the text. Like the artist, the research portraitist works to balance elements of context, thematic structure, relationship, and voice into an aesthetic whole that is so carefully constructed that every part seems an essential ingredient in the clarity of cohesive interpretation (Lawrence-Lightfoot & Davis, 1997).As a qualitative research methodology, portraiture is distinguished in part by this preoccupation with artistic coherence. The quest for coherence, for balancing a whole, plays a constant role in the researcher's efforts to construct a narrative that authentically portrays the central story of the subject or site. Portraiture is based on a belief in narratives or stories as primary and valid structures through which personal and professional identities are framed, sustained, and shared (see, e.g., Bruner, 1996). The narrative in portraiture is respected as an essential vehicle for meaning making in the life of the individual or group (Bateson, 1989;Lawrence-Lightfoot, 1994) and in the work of the attendant researcher. Narratives taken from literature are frequently used as foils for individual experience and as fodder for the interpretive process (see, e.g., Gilligan, 1982). In portraiture, however, the interpretive product (the research portrait) itself embodies artistic and literary elements. Simultaneously holding to empirical rigor and to artistic mandates, portraiture participates in a tradition of forging bridges across social science and art (Lawrence-Lightfoot & Davis, 1997).Portraiture may be regarded as embracing ethnographic objectives and techniques even as it rewrites both the form and function of traditional case Material from Davis et al. 1993 quoted by permission of Harvard University, Graduate School of Education.

The Bovine Respiratory Disease Coordinated Agricultural Project (BRD CAP) is a 5-year project funded by the United States Department of Agriculture (USDA), with an overriding objective to use the tools of modern genomics to identify cattle that are less susceptible to BRD. To do this, two large genome wide association studies (GWAS) were conducted using a case:control design on preweaned Holstein dairy heifers and beef feedlot cattle. A health scoring system was used to identify BRD cases and controls. Heritability estimates for BRD susceptibility ranged from 19 to 21% in dairy calves to 29.2% in beef cattle when using numerical scores as a semi-quantitative definition of BRD. A GWAS analysis conducted on the dairy calf data showed that single nucleotide polymorphism (SNP) effects explained 20% of the variation in BRD incidence and 17-20% of the variation in clinical signs. These results represent a preliminary analysis of ongoing work to identify loci associated with BRD. Future work includes validation of the chromosomal regions and SNPs that have been identified as important for BRD susceptibility, fine mapping of chromosomes to identify causal SNPs, and integration of predictive markers for BRD susceptibility into genetic tests and national cattle genetic evaluations.