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Pneumonia is an important issue for sheep production, leading to reduced growth rate and a predisposition to pleurisy. The objective of this study was to identify loci associated with pneumonic lesions and pleurisy in New Zealand progeny test lambs. The lungs from 3,572 progeny-test lambs were scored for presence and severity of pneumonic lesions and pleurisy at slaughter. Animals were genotyped using the Illumina Ovine Infinium HD SNP BeadChip (606,006 markers). The heritability of lung lesion score and pleurisy were calculated using the genomic relationship matrix, and genome-wide association analyses were conducted using EMMAX and haplotype trend regression. At slaughter, 35% of lambs had pneumonic lesions, with 9% showing lesions on more than half of any individual lobe. The number of lambs recorded as having pleurisy by the processing plants was 9%. Heritability estimates for pneumonic lesions and pleurisy scores adjusted for heteroscedasticity (CPSa and PLEURa) were 0.16 (± 0.03) and 0.05 (± 0.02), respectively. Five single-nucleotide polymorphisms (SNPs) were significantly associated with pneumonic lesions at the genome-wide level, and additional 37 SNPs were suggestively significant. Four SNPs were significantly associated with pleurisy, with an additional 11 SNPs reaching the suggestive level of significance. There were no regions that overlapped between the 2 traits. Multiple SNPs were in regions that contained genes involved in either the DNA damage response or the innate immune response, including several that had previously been reported to have associations with respiratory disease. Both EMMAX and HTR analyses of pleurisy data showed a significant peak on chromosome 2, located downstream from the transcription factor SP3. SP3 activates or suppresses the expression of numerous genes, including several genes with known functions in the immune system. This study identified several SNPs associated with genes involved in both the innate immune response and the response to DNA damage that are associated with pneumonic lesions and pleurisy in lambs at slaughter. Additionally, the identification in sheep of several SNPs within genes that have previously been associated with the respiratory system in cattle, pigs, rats, and mice indicates that there may be common pathways that underlie the response to invasion by respiratory pathogens in multiple species.

This review considers the application of new technologies to beef cattle and deer improvement. Many potential opportunities are linked to the concept of monitoring and then tracing the unique identity (ID) of livestock through the use of DNA methods and electronic IDs, including: identifying or confirming pedigrees; collection of field, yard or abattoir data linked to an electronic ID; marker-assisted selection using DNA and measured phenotypes; and trace-back facilities for meat products at the point of sale by matching a DNA sample taken there with one taken earlier in the abattoir. Opportunities with assisted reproduction are described, with the greatest potential payoffs being from much wider use of artificial insemination, provided that more practical and economical insemination methods can be found (especially in beef herds). Some new goal traits are considered which could become more important than at present, when applied to new production environments (e.g., selection to improve feed conversion efficiency, resistance to feed-borne toxins, resistance to nematode parasites, and deer calving earlier in the season). We conclude with a discussion of technology adoption for beef cattle and deer improvement. [ABSTRACT FROM AUTHOR]