Table 2. Increased endometrial EGF concentrations between Days 11 and 16 of the estrous cycle in dairy cows a.
| Cow No. | Days after estrus |
Pregnancy |
||||||
| 11 | 12 | 13 | 14 | 15 | 16 | 1st AI | 2nd AI | |
| 1 | – | – | + | + | – | – | + | NA |
| 2 | – | – | + | + | + | – | + | NA |
| 3 | – | – | + | + | + | – | − | − |
| 4 | – | + | + | + | – | – | − | + |
| 5 | – | – | + | + | – | – | − | + |
| 6 | – | – | + | + | – | – | + | NA |
| 7 | – | – | – | – | – | – | − | − |
| 8 | – | – | + | + | + | – | − | − |
| 9 | – | – | – | – | – | – | − | − |
| 10 | – | – | – | – | – | – | − | − |
a Endometrial EGF concentrations of ≥ 4.9 ng/g tissue weight (+) were considered as increased levels based on a normal range on Day 14 of the estrous cycle determined using data from 99 fertile cows [3]. NA: not applicable. Cows with odd and even numbers were subjected to repeated biopsies from positions A to F and from positions F to A, respectively (see Fig. 1).