Table 4.
Factors affecting conception rate and precision of female‐sexed semen
| 2012 | 2013 | 2014 | 2015 | 2016 | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| 23.3 | 48.6 | 31.9 | 38.1 | 43.0 | |||||||
| Rate of conception(%) | Average | % | Factor | % | Factor | % | Factor | % | Factor | % | Factor |
| Heifer rate (nonconception) | 56.3 | 63.0 | ↑ | 40.6 | ↓ | 77.8 | ↑ | 44.1 | ↓ | 57.4 | → |
| Use of female‐sexed semen | 50.3 | ― | ― | 63.5 | ↓ | 64.6 | ↓ | 49.0 | → | 28.9 | ↑ |
| Insemination with female‐sexed semen 2 or more times (%) | 38.3 | ― | ― | 23.3 | ↑ | 45.9 | ↓ | 41.5 | → | 40.0 | → |
| Semen accuracy | % | Factor | % | Head | % | Head | % | Head | % | Head | |
| Number of births from use of sex‐sorted Semen (number of female calves produced) | 73.8 | ― | 44.4 | 9(4) | 78.3 | 23(18) | 73.3 | 15(11) | 83.3 | 18(15) | |
| Number of births from nonsorted semen (number of female calves produced) | 53.5 | ― | 100.0 | 6(6) | 63.6 | 11(7) | 36.4 | 11(4) | 40.0 | 15(6) | |
| Rate of female calves birthed (%) | 65.7 | ― | 66.7 | 73.5 | 57.7 | 63.6 | |||||
Note. The average rate of nonfertile cattle is 56.3%, and the average sex‐selected semen utilization rate is 50.3%.
Source: Ozasa Farm Individual Breeding Control Registers.