Table 2.

M. synoviae antibody of native broilers infected by infectious synovitis in China

Group	Breed	No. of farma	Age (day)	Clinical signs	Type of sample	No. of positive M. synoviae antibody	Positive proportion	Sampling time
A1	Tianlu	8	35–60	Arthrocele	Serum	79/103	76.70%	2012.01–2014.12
A2	Tianlu		35–60	NO	Serum	88/131	67.18%	2012.01–2014.12
B1	San Huang	17	30–75	Arthrocele	Serum	208/299	69.57%	2010.10–2014.12
B2	San Huang		30–75	NO	Serum	78/252	30.95%	2010.10–2014.12
C1	Silky	5	31–63	Arthrocele	Serum	59/62	95.16%	2012.06–2014.12
C2	Silky		31–63	NO	Serum	30/80	37.5%	2012.06–2014.12
D1	Hua	9	40–71	Arthrocele	Serum	140/155	90.32%	2012.02–2014.12
D2	Hua		40–71	NO	Serum	81/128	63.28%	2012.02–2014.12
E1	Qingyuan Ma	14	29–62	Arthrocele	Serum	197/240	82.08%	2011.03–2014.12
E2	Qingyuan Ma		29–62	NO	Serum	112/238	47.06%	2011.03–2014.12
Total		53				1072/1696	63.20%	2010.10–2014.12

^aThirty-two blood samples were collected from each farm, including 16 samples from sick chickens with typical clinical signs and 16 samples from chickens without any clinical symptoms