Table 1.
Effect of late gestation supplementation on cow body weight, body condition score, and reproductive performance.
| Treatment1 | ||||||
| Measurement | NoSupp | Supp | CaProp | RUM | SEM | P-value |
| Cows, n | 105 | 86 | 80 | 86 | ||
| Cow body weight, kg | ||||||
| Initial2 | 503 | 505 | 504 | 501 | 7.3 | 0.87 |
| Pre-calving3 | 490b | 535a | 535a | 529a | 6.8 | < 0.01 |
| Pre-breeding4 | 473b | 499a | 491a | 491a | 6.8 | < 0.01 |
| Weaning5 | 513 | 519 | 513 | 512 | 6.8 | 0.93 |
| Body weight change, kg | ||||||
| Initial to Pre-calving | −12.7b | 29.1a | 30.9a | 27.3a | 5.45 | < 0.001 |
| Pre-calving to Pre-breeding | −17.7a | −35.5b | −43.6b | −37.3b | 5.91 | < 0.01 |
| Pre-breeding to Weaning | 40.0a | 20.0b | 22.3b | 20.5b | 5.00 | 0.01 |
| Cow BCS | ||||||
| Initial | 5.3 | 5.4 | 5.4 | 5.4 | 0.05 | 0.18 |
| Pre-calving | 4.8b | 5.3a | 5.4a | 5.3a | 0.06 | < 0.01 |
| Pre-breeding | 5.0b | 5.3a | 5.3a | 5.3a | 0.05 | < 0.01 |
| Weaning | 5.3 | 5.4 | 5.4 | 5.5 | 0.33 | 0.46 |
| Pregnancy rate, % | 90b | 96a | 95a | 91b | -- | 0.09 |
1Treatment = No supplementation (NoSupp), 0.91 kg/d of a 30% crude protein distillers-based supplement (Supp), 0.91 kg/d of a 30% crude protein distillers-based supplement with 160 mg/cow/d of monensin (RUM; Rumensin 90, Elanco Animal Health, 0.91 kg/d of a 30% crude protein distillers-based supplement with 40 g/cow/d propionate salt (CaProp; NutroCal 100, Kemin Industries).
2Initial BW = BW recorded at weaning in November prior to the initiation of late gestation supplementation treatments.
3Pre-calving = BW recorded in February.
4Pre-breeding = BW recorded in May.
5Weaning = BW recorded in November.
abFor each treatment interaction, means in rows with different superscripts differ (P ≤ 0.05).