A large seroprevalence survey of brucellosis in cattle herds under diverse production systems in northern Nigeria

BMC Veterinary Research

Table 3 Animal-level seroprevalence of brucellosis in cattle in three states of northern Nigeria, by breed, sex, age, management system, pregnancy status and lactation status, adjusted for sampling weights and test sensitivity and specificity

Variable and level	n	Adjusted prev. (%)	95% CI (%)	P-value*
All Animals
State				0.496
Adamawa	1827	29.2	22.5-36.9
Kaduna	1870	23.3	18.9-28.3
Kano	1048	26.7	18.8-36.7
Management system				<0.001
Zero-grazing	101	23.8^ab	6.8-59.2
Commercial	642	15.9^a	9.5-25.5
Agro-pastoral	2758	22.0^a	17.3-27.8
Pastoral	1244	45.1^b	38.6-51.9
Breed				0.392
Bunaji	3052	27.5	22.5-33.2
Gudali	863	26.3	22.1-31.1
Bos taurus	118	15.1	6.6-31.0
B. taurus x B. indicus	267	21.8	11.7-37.0
Other B. indicus	445	24.7	17.8-33.5
Sex				<0.001
Males	596	38.2^a	31.7-45.2
Females	4149	24.7^b	20.4-29.5
Age				<0.001
< 4 years	559	13.5^a	8.9-19.9
4 - 5 years	2038	23.8^b	19.9-28.1
5 - 7 years	1312	29.8^c	22.6-38.2
> 7 years	804	35.0^c	28.5-42.3
Females Only
Pregnancy status				<0.001
Pregnant	1367	17.2^a	13.6-21.5
Non-pregnant	2835	27.8^b	22.9-33.5
Lactation status				0.635
Lactating	1819	25.3	20.7-30.5
Non-lactating	2386	23.2	19.3-29.9
Total	4745	26.3	22.1-31.0

Figures with different superscripts within the same variable differ significantly (P < 0.05).
* P-value determined using the Chi-square test, corrected for the survey design using the second-order correction of Rao and Scott [53].

ISSN: 1746-6148