Lung consolidation effect on beef × dairy calves
Lung consolidation at weaning has short-term effects on beef × dairy calf growth
14 May 2024
2 minute read
By: A recent study evaluated the impact of lung consolidation at weaning on average daily gain (ADG) of 145 beef × Holstein calves. The study was done by I.L.B. Fernandes and fellow students at Penn State University; the results were presented at the 2024 Tri-State Dairy Conference.
Calves were sourced from two dairies and raised in three cohorts. Calf health (diarrhea, bovine respiratory disease) was assessed after arrival (1 to 4 days of age), at 61 ± 14 day (4 days post-weaning), 83 ± 21 days, and 238 ± 21 days.
Calves received a thoracic ultrasonography scan (TUS) at period 1 to assess for lung consolidation (TUS+ ≥ 1 cm in one lobe), and lung consolidation severity (LCS; none, 1 to 2 cm, or 3 cm).
Calves were fed milk replacer (0.84 kg/day) and had ad-lib access to starter and water in buckets.
At 4 ± 2 day post-weaning, calves were moved to a separate rearing facility. Calf ADG was calculated into periods: arrival weight – weaning weight /day (period 1), weaning weight – 83 day weight/day (period 2), and 83 day weight – 238 day weight /day (period 3).
Period and sire breed were fixed effects, serum total protein and birthweight were covariates, and calf nested within the cohort was a random effect. There were 36 TUS+ calves and LCS was 109 healthy, 10 = 1 to 2 cm, and 26 = 3 cm.
There was a TUS+ × period interaction (P ≤ 0.001). Period 1 ADG was not different (healthy 0.57 ± 0.02, TUS+ 0.56 ± 0.03 kg/day, P = 0.99). However, healthy calves grew 0.13 (± 0.04) kg/day more in period 2 than TUS+ calves (P <0.01). Period 3 ADG was not different (healthy 1.20 ± 0.02, TUS+ 1.28 ± 0.03 kg/day, P = 0.14).
There was also an LCS × period interaction (P ≤ 0.001), with significant differences between LCS in period 2 (P < 0.001). Specifically, period 2 healthy calves had greater ADG (1.18 ± 0.02 kg/day) than LCS at 3 cm (1.05 ± 0.04 kg/day P = 0.02); LCS at 1 cm were similar (P > 0.10). The final weight of the cattle at period 3 was 323.51 ± 36.63 kg (mean ± SD).
The results of the study suggest that lung consolidation at weaning has short-term effects on beef × dairy calf growth, but compensatory growth nullifies the impact within 238 days of age.
