Fertility in Gyr Cows (Bos indicus) with Fixed Time Artificial Insemination and Visual Estrus Detection Using a Classification Table

Table 3

Odds ratios and confidence intervals for factors associated with FSF in cows under insemination based on fixed time or natural estrus observation applying a rating score table.

Predictor; levels	Estimators		Probability of the likelihood ratio	Somers’; D
	ODDS ratio	95% confidence interval
SC-FTAI	1.050	0.595–1.855	0.4435	0.178
NSE-AI
PPA ≤ 100 d	0.802	0.382–1.687
PPA > 100 d
DMY ≥ 6 k/L/d	0.509	0.266–0.971
DMY < 6 k/L/d
BCAI ≥ 2.5	0.850	0.440–1.642
BCAI < 2.5
CN ≤ 3	0.832	0.479–1.445
CN > 3
Logistic prediction equation:

AIP = protocol type: SC-FTAI: synchronized cows and fixed time artificial insemination; NSE-AI: natural estrus observation applying rating score table; PPA: postpartum anestrous; DMY: daily milk yield; BCAI: body condition at AI time; CN: calving number.