Table 2.

Laboratory parameters of the heifer, renal excretion of electrolytes

	plasma [mmol/l]	urine [mmol/l]	FE [%]	FE [%] reference in calves [7]
creatinine	0.139	14.39
sodium	155.5	140.5	0.87	0.0–2.7
calcium	2.49	0.78	0.3	0.0–2.2
phosphor	0.84	3.39	4.22	2.7–23.6
potassium	3.47	364.5	94.14	15–85

Increased fractional excretion (FE) is a hint for increased elimination of electrolytes due to renal failure

$FEelectrolyt=\frac{\left(e,l,e,c,t,r,o,l,y,t,,u,r,i,n,e,*,c,r,e,a,t,i,n,i,n,e,,p,l,a,s,m,a\right)}{\left(e,l,e,c,t,o,l,y,t,,p,l,a,s,m,a,*,c,r,e,a,t,i,n,i,n,e,,u,r,i,n,e\right)}*100$