|Hall, Mary Beth|
Submitted to: Journal Dairy Science Supplement
Publication Type: Abstract Only
Publication Acceptance Date: 2/25/2011
Publication Date: 7/10/2011
Citation: Hall, M., Oetzel, G.R., Huntington, G.B., Moore, F.M., Hertzke, D.M. 2011. Associations among digestive tract lesions and abnormal serum chemistries in cull dairy cattle. Journal of Dairy Science. 94(E-Supplement 1):368. Interpretive Summary:
Technical Abstract: All animals accrue tissue damage with age, but types and prevalence of damage are not known. Tissue lesions could signal impaired organ function which could affect performance. The study objective was to assess prevalence of microscopic lesions in digestive tracts of cull dairy cows, and determine associations among lesions and with abnormal serum chemistry values. Cull dairy cows (79) were sampled at 3 commercial abattoirs on 5 occasions. Tissue samples from reticulorumen (RR), small intestine (SI), large intestine, pancreas (PAN), cecum, and liver (LIV), and a blood sample were obtained immediately postmortem. Additionally, jugular blood samples and RR biopsies of papillae were obtained from 19 clinically normal live, noncull, ruminally cannulated Holsteins (11 lactating cows and 8 non-lactating bred heifers). Associations among lesions and with serum chemistries were evaluated with logistic regression analysis. Odds ratios for pairs of lesions described the increased likelihood of presence of both if one was found. Infiltration by lymphocytes observed in all SI, large intestinal and cecal samples suggests that this is normal, possibly related to barrier immune function. Serum chemistries were generally not good predictors of specific tissue lesions. Noncull animals had lower prevalence of RR inflammation and pustules than cull cows (P<0.03). For cull animals, no lesions were detected in 36% of RR, 49% of SI, and 64% of PAN samples. Only 8% of LIV samples showed no lesions. Associations among lesions were found between RR and PAN, and among PAN, SI, and LIV. Among the odds ratio results: 4.7 for RR pustules and PAN inflammation (P=0.12), 8.7 for SI hemosiderin laden macrophages (HLM) and decreased PAN zymogen (P<0.01), and 3.0 for HLM and LIV mineralization (P=0.06). Interrelatedness of lesion prevalence suggests that impact of disorders that created the lesions was not confined to a single organ. With implications for improved animal health, well-being, longevity, and performance, further investigation is warranted into how treatment or prevention of primary disorders and traits of economic importance relate to development of tissue damage.