Table 6. Overall effect of rumen-protected methionine (RPM) treatment on fertility responses and pregnancy loss in lactating dairy cows.
| Treatment1 | |||
|---|---|---|---|
| Item [% (n/total n)] | CON | RPM | P-value |
| Overall | |||
| P/AI at 28 days | 65.5 (91/139) | 66.7 (96/144) | 0.42 |
| P/AI at 32 days | 58.6 (82/140) | 61.4 (89/145) | 0.32 |
| P/AI at 47 days | 56.1 (78/139) | 59.7 (86/144) | 0.27 |
| P/AI at 61 days | 54.4 (75/138) | 58.3 (81/139) | 0.26 |
| Pregnancy loss | |||
| 28 and 61 days | 16.7 (15/90) | 10.0 (9/90) | 0.08 |
| 32 and 61 days | 7.4 (6/81) | 2.4 (2/83) | 0.10 |
| Primiparous | |||
| P/AI at 28 days | 63.5 (40/63) | 66.7 (42/63) | 0.35 |
| P/AI at 32 days | 58.7 (37/63) | 60.3 (38/63) | 0.43 |
| P/AI at 47 days | 56.5 (35/62) | 57.1 (36/63) | 0.47 |
| P/AI at 61 day | 54.8 (34/62) | 56.5 (35/62) | 0.43 |
| Pregnancy loss | |||
| 28 and 61 days | 12.8 (5/39) | 14.6 (6/41) | 0.41 |
| 32 and 61 days | 5.6 (2/36) | 5.4 (2/37) | 0.50 |
| Multiparous | |||
| P/AI at 28 days | 67.1 (51/76) | 66.7 (54/81) | 0.48 |
| P/AI at 32 days | 58.4 (45/77) | 62.2 (51/82) | 0.31 |
| P/AI at 47 days | 55.8 (43/77) | 61.7 (50/81) | 0.23 |
| P/AI at 61 days | 54.0 (41/76) | 59.7 (46/77) | 0.23 |
| Pregnancy loss | |||
| 28 and 61 days | 19.6 (10/51) | 6.1 (3/49) | 0.03 |
| 32 and 61 days | 8.9 (4/45) | 0.0 (0/46) | 0.03 |
1Treatments: Control (CON) = feeding with 60 g of dried distillers grain (1.87% Met of MP); and Rumen-protected methionine (RPM) = 21.2 g of rumen-protected methionine (Smartamine M, 2.34% Met of MP) + 38.8 g of dried distillers grain.