Mycoplasma bovis antibody dynamics in naturally exposed dairy calves according to two diagnostic tests

BMC Veterinary Research

Table 1 Summary description of the four Danish dairy herds and diagnostic test results prior to and during the study period

Herd no.	1	2	3	4
Prior to enrolment
Herd size (No. of cows)	177	174	182	391
Estimated start of outbreak	Early Jun 2015	Early Jul 2015	Late Nov 2015	Mid Dec 2015
After enrolment
Data collection	1 Jul 2015–16 Sep 2016	20 Jul 2015–6 Oct 2015	8 Dec 2015–23 Feb 2016	20 Jan 2016–5 Apr 2016
Age group primarily affected	Cows	Cows and calves	Cows	Cows and calves
Primary clinical signs
Cows	Mastitis	Mastitis, arthritis	Arthritis	Mastitis, arthritis
Calves	Pneumonia, otitis media	Arthritis, otitis media, pneumonia	Few cases of arthritis and otitis media	Arthritis, otitis media, pneumonia
Diagnostic tests
Number of calves	15	22	20	26
Number of samples	51	101	89	93
Positive samples^a
BioX^b	16	26	14	13
MilA^c	48	98	41	88
Positive cultures from necropsied calves (total necropsied calves)	0 (0)	1 (1)	0 (2)	2 (2)

^aNumber of seropositive samples out of all sera obtained during the study period
^bODC% values > 37 in BioX Bio K 302 ELISA (BioX Diagnostics, Belgium)
^cAU > 135 in the MilA ELISA

ISSN: 1746-6148