Local host response following an intramammary challenge with Staphylococcus fleurettii and different strains of Staphylococcus chromogenes in dairy heifers

Table 2 Linear mixed regression model for somatic cell count, bacterial count, apoptotic and necrotic neutrophils

Predictor variables	Ln SCC (cells/µL)				Log (CFU/mL + 1)				Ln apoptotic PMN (%)				Ln necrotic PMN (%)
Predictor variables	β^a	SE^b	LSM^c	P	β	SE	LSM	P	β	SE	LSM	P	β	SE	LSM	P
Intercept	3.43	0.34	–	<0.01^d	0.52	0.16	–	<0.01^d	3.16	0.19	–	<0.01^d	2.72	0.11	–	<0.01^d
Inoculum				<0.01^d				<0.01^d				<0.01^d				<0.01^d
Control	Ref.^e	–	3.91	–	Ref.	–	−0.03	–	Ref.	–	3.48	–	Ref.	–	3.15	–
S. fleurettii			6.07	<0.01^f			0.22	0.25^f			2.85	0.01^f			2.79	0.03^f
S. chromogenes TA			5.78	<0.01^f			0.50	<0.01^f			3.06	0.13^f			2.90	0.29^f
S. chromogenes IM			6.71	<0.01^f			0.89	<0.01^f			2.92	0.02^f			2.85	0.10^f
Time of sampling	0.06	0.01	–	<0.01^d	−0.05	0.01	–	<0.01^d	0.01	0.00	–	<0.01^d	0.02	0.15	–	<0.01^d
Quadratic term of time of sampling	0.00	0.00	–	<0.01^d	0.00	0.00	–	<0.01^d				NS^g				NS
Inoculum × time of sampling	–	–	–	<0.01^d	–	–	–	<0.01^d	–	–	–	0.02^d	–	–	–	0.01^d

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