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Objective: The purpose of this study was to evaluate potential relationships between cytokine gene expression, complete blood counts (CBC) and animals that were sick or would become sick. The CBC and the transcript abundance of cytokines and their receptors expressed in leukocytes were measured from calves at two early timepoints, and again after diagnosis with bovine respiratory disease (BRD)., Results: Blood was collected from calves at pre-conditioning (n = 796) and weaning (n = 791) for CBC. Blood counts were also measured for the calves with BRD (n = 13), and asymptomatic calves (n = 75) after weaning. The CBC were compared for these animals at 3 time points. At diagnosis, neutrophils were higher and basophils lower in sick animals (P < 0.05). To further characterize BRD responses, transcript abundance of 84 cytokine genes were evaluated in 5 calves with BRD and 9 asymptomatic animals at all time points. There was more data for CBC than transcript abundance; hence, animal and temporary environmental correlations between CBC and transcript abundance were exploited to improve the power of the transcript abundance data. Expression of CCL16, CXCR1, CCR1 was increased in BRD positive animals compared to controls (P-corrected < 0.1). Cytokine expression data may help to provide insight into an animal's health.

Background: Classical and atypical bovine spongiform encephalopathies (BSEs) are cattle prion diseases. Distinct bovine prion gene (PRNP) alleles have been associated with classical and atypical BSE susceptibility. However, the full extent of PRNP allele association with BSE susceptibility is not known. A systematic sequence-based genotyping method that detects variation throughout PRNP would be useful for: 1) detecting rare PRNP alleles that may be present in BSE-affected animals and 2) testing PRNP alleles for an association with either classical or atypical BSE susceptibility., Findings: We improved a Sanger-based sequencing strategy for detecting bovine PRNP variation through all exons, introns, and part of the promoter (25.2 kb). Our current method can detect 389 known and other potentially unknown PRNP polymorphisms that may be present in BSE-affected cattle. We determined PRNP genotypes for the first U.S. BSE case and her sire. Previously unknown PRNP polymorphisms were not detected in either animal and all PRNP genotypes support the sire-daughter relationship., Conclusion: The methodologies described here characterize variation throughout PRNP. Consequently, rare PRNP alleles that may be present in BSE-affected cattle can be detected.