Table 6 Gastrointestinal scores (mean ± SD), following a single oral administration of saline, single oral administration of codeine (0.3, 0.6 and 1.2 mg/kg) or a single intravenous administration of morphine (0.2 mg/kg) to 7 adult horses

Baseline

2.7 ± 0.8

2.7 ± 8

1.7 ± 0.5

2.4 ± 1.3

2.4 ± 1.5

0.5

3.4 ± 1.5

3.0 ± 0.8

2.3 ± 1.0

2.6 ± 0.8

1.4 ± 1.4

0.75

3.4 ± 1.3

3.0 ± 0.6

1.9 ± 0.7

2.0 ± 0.6

1.9 ± 1.7

1

3.1 ± 1.3

2.7 ± 1.8

2.6 ± 0.8

1.7 ± 0.8

1.6 ± 0.5

2

3.9 ± 0.7^*

2.9 ± 0.7

2.7 ± 1.0

2.4 ± 0.8

2.1 ± 1.3

4

3.9 ± 0.7^*

3.6 ± 1.0

4.0 ± 0.8^*

3.4 ± 0.8

3.9 ± 1.1^*

6

3.7 ± 1.0^*

3.3 ± 0.8

3.4 ± 0.8^*

3.4 ± 1.1

3.4 ± 1.4

24

–

4.0 ± 0.8^*

3.3 ± 1.7^*

3.0 ± 1.5

3.3 ± 0.5