Table 5.

Model 2: Linear regression model for average daily milk yield within the Langhill herd in 157 heifers calving during the time period August 2003 to March 2006, with herd lifetime data recorded from September 2003 to August 2011 at the SRUC Dairy Research and Innovation Centre herd.

Intercept		Coefficient: 19.72
Variable	Na	Mean effect	Lower 95% CIb	Upper 95% CI
Sole Lesion (2 to 4 months post-calving)
0 to 1	24	Baseline
2	35	−0.76	−3.03	1.50
3	32	0.008	−2.29	2.30
4 to 8	27	−2.68	−5.05	−0.31
Digital dermatitis (2 to 4 months post-calving)
0	98	Baseline
1 to 3	20	2.63	0.51	4.75
Feed − genetic groupc
LF:C	30	Baseline
LF:S	36	10.57	7.99	13.14
HF:C	30	−1.41	−3.87	1.05
HF:S	32	2.737	0.27	5.21

^aN = Number of heifers with lesions observed within each category.

^bCI = confidence interval. Parameter is ‘significant' if the 95% confidence interval excludes 0.

^cFeed-genetic groups include low forage (LF), high forage (HF), control (C), and select (S).