Ectoparasites of European hedgehogs (Erinaceus europaeus) in Germany and their health impact

Parasites & Vectors

Table 4 Results of the binomial generalised linear models testing the influence of sampling month, sampling year, sex, age, weight and health status on the infestation rates of European hedgehogs with adult and nymphal I. ricinus

Variables tested in GLM model	GLM Model A: I. ricinus adults^a				GLM Model B: I. ricinus nymphs^a
Variables tested in GLM model	Estimate	SE	Z	P	Estimate	SE	Z	P
Intercept	− 1.17	0.96	− 1.22	0.223	− 2.19	1.36	− 1.61	0.108
Sampling month (reference month: January)
February	0.39	0.80	0.49	0.627	1.94	1.18	1.65	0.100
March	0.76	0.77	0.99	0.320	2.54	1.15	2.22	0.026*
April	1.99	0.70	2.83	0.005*	4.12	1.12	3.69	< 0.001*
May	2.50	0.71	3.50	< 0.001*	3.58	1.10	3.25	0.001*
June	2.03	0.75	2.71	0.007*	2.97	1.13	2.64	0.008*
July	0.92	0.72	1.27	0.205	2.29	1.12	2.04	0.041*
August	0.71	0.77	0.92	0.358	2.60	1.15	2.25	0.024*
September	0.47	0.75	0.63	0.531	2.49	1.13	2.20	0.028*
October	0.83	0.72	1.15	0.251	1.41	1.14	1.23	0.217
November	− 0.93	0.76	− 1.21	0.226	0.07	1.20	0.06	0.953
December	− 0.80	0.90	− 0.89	0.376	− 14.48	577.10	− 0.03	0.980
Sampling year (reference year: 2018)
2019	− 0.43	0.42	− 1.02	0.310	− 0.92	0.48	− 1.92	0.055
2020	− 0.35	0.42	− 0.82	0.413	− 1.32	0.48	− 2.75	0.006*
2021	− 0.32	0.60	− 0.53	0.598	− 1.68	0.64	− 2.61	0.009*
Sex (reference: male)	− 0.20	0.23	− 0.86	0.392	− 0.33	0.24	− 1.38	0.168
Age (reference age: subadult)	− 0.89	0.42	− 2.13	0.033*	− 0.18	0.41	− 0.44	0.661
Weight	< 0.01	< 0.01	2.60	0.009	< 0.01	< 0.01	1.15	0.250
Health status (reference status: health not impaired)
Moderately impaired	0.21	0.66	0.31	0.753	0.45	0.77	0.58	0.560
Severely impaired	< 0.01	0.67	< 0.01	0.999	0.49	0.77	0.64	0.525

GLM Generalised linear model, SE Standard Error
*Statistically significant at P ≤ 0.05
^aBoth models were significantly different from a null model. Model A: Chi-square = 79.25, df = 19, P < 0.001¸ Model B: Chi-square = 109.03, df = 19, P < 0.001

ISSN: 1756-3305