Table 4.

Univariable logistic regression analysis of potential risk factors of brucellosis in breeding female cattle in the study areas.

Variable	Category	Total animals examined	Total animals positive (%)	Crude OR (CI 95%)	P-value
Origin	Lemu Seka	249	12 (4.8%)	–	–
	Chora Boter	174	5 (2.9)	1.7 (0.59–4.95)	0.321
Age					0.033
	<3 years	29	4 (13.8)	–	–
	3–6 years	204	8 (3.9)	3.9 (1.10–13.96)	0.035
	>6 years	190	5 (2.6)	5.9 (1.49–23.52)	0.012
Breed	Cross	116	10 (8.6)	–	–
	Local	307	7 (2.3)	4.0 (1.50–10.89)	0.006
BCS					0.269
	Good	54	4(7.4)	–	–
	Medium	264	11(4.2)	1.8 (0.56–6.01)	0.313
	Poor	105	2(1.9)	4.1 (0.73–23.23)	0.109
Parity					0.216
	Nulliparous	184	11(6.0)	–	–
	Monoparous	112	3(2.7)	2.3 (0.63–8.47)	0.206
	Pluriparous	127	3(2.4)	2.6 (0.72–9.62)	0.144
Pregnancy status	Non-pregnant	165	11(6.7)	–	–
	Pregnant	258	6 (2.3)	3.0 (1.09–8.28)	0.034
Abortion history	No	282	8(2.8)	–	–
	Yes	141	9(6.4)	0.4 (0.16–1.14)	0.088
Abortion period					0.070
	No history	282	8(2.8)	–	–
	Before 5th month	44	1(2.3)	1.3 (0.15–10.29)	0.832
	After 5th month	97	8(8.2)	0.3 (0.12–0.89)	0.029
Retained placenta	No	294	9(3.1)	–	–
	Yes	129	8(6.2)	0.5 (0.18–1.27)	0.138
Agro-ecology	Mid-altitude	351	16(4.6)	–	–
	Lowland	71	1(1.4)	3.4 (0.44–25.99)	0.240
Management system	Sem-intensive	222	10(5.0)	–	–
	Extensive	201	7 (3.2)	1.6 (0.60–4.31)	0.345
Introduction of new animal	No	134	8(6.0)	–	–
	Yes	289	9(3.1)	2.0 (0.75–5.24)	0.171
Herd size					0.076
	Small	180	12(6.7)	–	–
	Medium	126	4(3.2)	2.2 (0.69–6.92)	0.187
	Large	117	1(0.9)	8.3 (1.06–64.60)	0.044
Species composition	Only cattle	40	5(12.5)	–	–
	Mixed with sheep and/ goat	383	12(3.1)	4.4 (1.47–13.26)	0.008

OR: Odds Ratio; CI: Confidence Interval, BCS: Body condition score.