title: Short communication: Ultrasonographic assessment of lung consolidation postweaning and survival to the first lactation in dairy heifers.
abstract: The aim of this prospective cohort study was to assess the association of systematic thoracic ultrasonography findings postweaning on calves' survivability to the first lactation. Three-month-old Jersey heifers (n=250) returning from a custom heifer grower were scanned by thoracic ultrasonography and lungs assessed using a scoring system with a scale from 1 to 4. A score of 1 was attributed to calves with no abnormality. A score of 2 was assigned if multiple comet tails or B-lines (coalescence of multiple comet tails) were observed. A score of 3 was assigned to calves with ≥1 location of lung consolidation ≥1 cm but <6 cm. Calves with extensive consolidation (≥6 cm in one or more locations) or evidence of abscessation or pleural effusion (>1 cm) were assigned a score of 4. Calves with a score of 4 had greater risk of dying or being culled [26% (95% credibility interval: 13-47%)] than calves with a score of 1 [1% (0-6%)], 2 [3% (1-9%)], or 3 [5% (1-17%)]. We found no association between age of first calving in the remaining calves and lung score. Thus, lung lesion severity assessed by thoracic ultrasound is associated with a long-term production outcome.
authors.affiliation: Dairy Technical Services Team, Merck Animal Health, 35500 W 91st Street, De Soto, KS 66018. Electronic address: elizabeth.adams@merck.com.
authors.forename: E A
authors.initials: EA
authors.lastname: Adams
authors.affiliation: Département des sciences cliniques, Faculté de Médecine Vétérinaire, Université de Montréal, CP5000, Saint-Hyacinthe, J2S 7C6, Québec, Canada.
authors.forename: S
authors.initials: S
authors.lastname: Buczinski
mesh_terms: D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000000981:diagnostic imaging* / Q000503:physiopathology; D015331:Cohort Studies; D005260:Female; D007774:Lactation; D008168:Lung / Q000000981:diagnostic imaging / Q000503:physiopathology; D008171:Lung Diseases / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000662:veterinary*; D010996:Pleural Effusion / Q000000981:diagnostic imaging / Q000503:physiopathology / Q000662:veterinary; D011446:Prospective Studies; D014463:Ultrasonography; D014886:Weaning
keywords: dairy calf; lung consolidation; pneumonia; ultrasonography