Table 3 Multivariable linear regression model of the effect of infection with different Trypanosoma species and other significant confounding factors on the packed cell volume (PCV) of 241 horses and donkeys from the Central River Division, The Gambia 2006.

Intercept

36.1

1.2

T. congolense

-ve

Ref

+ve

-11.9

0.8

<0.001

T. Brucei sp

-ve

+ve

-2.0

0.9

0.03

T. vivax

-ve

Ref

+ve

-3.3

1.2

0.007

Gender

Male

Ref

Female

-1.6

0.7

0.03

Species

Horse

Ref

Donkey

-1.9

0.8

0.02

Trypanosoma status on microscopic examination

-ve

Ref

+ve

-5.3

1.0

<0.001

T. congolense* T. vivax interaction term

Ref

+ve

6.4

2.3

0.006