Table 4.
Mean temperature–humidity index (THI) thresholds associated with conception rates (CR) of heifers and multiparous cows
| THI threshold | Number of animals (N) | CR (%) | ||
|---|---|---|---|---|
|
|
|
|||
| Heifers | Multiparous cows | Heifers | Multiparous cows | |
| Mean THI <60 | 8 | 57 | 61.26 | 52.21 |
| Mean THI 60–65 | 20 | 84 | 58.41 | 51.15 |
| Mean THI 66–70 | 31 | 79 | 56.15 | 49.13 |
| Mean THI 71–75 | 21 | 82 | 57.72 | 46.82 |
| Mean THI 76–80 | 13 | 75 | 54.42 | 42.26 |
| Mean THI >80 | 12 | 60 | 52.61 | 40.41 |
| Mean THI ≤72 | 65 | 225 | 59.14 | 50.68 |
| Mean THI >72 | 40 | 212 | 55.12b | 43.84a |
CR: conception rate (pregnancy per artificial insemination service).
a,b
Means with different superscripts in the same row differ at p<0.05.