Table 4 Serum antibody titer of Broiler PS (Parent stock) used in the experiment

A farm
Age of chickenA	Flock 1			Flck 2				Flock 3				Flock 4
	Multinational ELISA kitB	DomesticELISA kitC		Multinational ELISA kit		DomesticELISA kit		Multinational ELISA kit		DomesticELISA kit		Multinational ELISA kit		DomesticELISA kit
48 weeks	5428	6726		5229		6066		6327		7005		6978		7168
60 weeks	8031	8414		8087		7549		657		7907		6629		8316
Die out	7918	7598		7467		5889		7073		6335		6509		5492
B farm
Age of chicken	Flock 1			Flock 2				Flock 3				Flock 4
	Multinational ELISA kit	DomesticELISA kit		Multinational ELISA kit		DomesticELISA kit		Multinational ELISA kit		DomesticELISA kit		Multinational ELISA kit		DomesticELISA kit
36 weeks	5411	6162		4486		5987		2951		5097		3008		4284
48 weeks	7085	6803		6458		6681		19891		12315		4153		5034
60 weeks	7677	6206		5345		4380		4380		5126		8838		7493
C farm
Age of chicken	Flock 1			Flock 2				Flock 3				Flock 4
	Multinational ELISA kit	DomesticELISA kit		Multinational ELISA kit		DomesticELISA kit		Multinational ELISA kit		DomesticELISA kit		Multinational ELISA kit		DomesticELISA kit
1 week	7036	7105		4807		6425		4833		7787		7231		8089
3 weeks	199	246		63		43		383		436		246		470
5 weeks	168	467		617		2117		251		681		172		337
7 weeks	122	158		463		1559		1660		2554		272		289
10 weeks	923	1896		1906		4580		727		2578		1011		1987
14 weeks	1261	1972		2744		4348		1914		2977		876		1435
18 weeks	2204	3388		3346		5756		2953		3863		688		1202

^A Age of chickens: The age of chicken when the samples were collected.
^B Multinational ELISA kit: ELISA titer of Infectious bronchitis virus antibodies in serum analyzed by a multinational corporation ELISA kit.
^C Domestic ELISA kit: ELISA titer of Infectious bronchitis virus antibodies in serum analyzed by a Domestic corporation ELISA kit.