Table 1.

Descriptive characteristics of studied populations relevant for sampling planning, number of samples collected and E. coli isolates used in the study.

Characteristics	Target animal	Year
		2008	2009	2010	2011	2012
Number of animals slaughtered in Poland	Broilers	554846197	578970522	633640413	666313527	723764340
	Layers	29550379	26353151	33890429	37311263	39056653
	Turkeys	27244356	22926577	25339326	25287042	27780566
	Swine	19525920	17420288	19488804	20038278	20094157
	Cattle	1601569	1492360	1580467	1523384	1578773
Number of slaughterhouses in Poland	Broilers	178	159	160	156	155
	Layers	51	44	43	40	37
	Turkeys	37	34	29	26	24
	Swine	912	706	694	682	662
	Cattle	440	355	349	351	340
Slaughter capacity threshold*	Broilers	3650000	2200000	2100000	2 200 000
	Layers	70000	100000	50000	30 000
	Turkeys	700000	250000	100000	90 000
	Swine	19300	35000	39000	45 000
	Cattle	3600	4750	4800	4 950
Number of abattoirs designated for sampling and their contribution to annual slaughter capacity (%)**	Broilers	47 (80%)	61(85%)	66 (90%)	63 (90%)
	Layers	7 (50%)	20 (95%)	20 (99%)	27 (99%)
	Turkeys	15 (80%)	21 (95%)	23 (99%)	22 (99%)
	Swine	200 (80%)	109 (70%)	94 (70%)	81 (70%)
	Cattle	91 (80%)	79 (80%)	78 (80%)	72 (80%)
Number of samples collected and proceeded	Broilers		180	186	192	195
	Layers		162	194	181	179
	Turkeys		180	188	194	189
	Swine		181	176	189	194
	Cattle		174	179	176	191
Number of tested E.coli isolates	Broilers		171	170	170	171
	Layers		157	169	155	157
	Turkeys		173	170	170	180
	Swine		178	170	172	190
	Cattle		173	171	173	190

^*Minimal number of animals slaughtered at abattoir to consider designation of slaughterhouse for sampling.

^**Estimated contribution (%) of designated abattoirs to annual national production of slaughtered animals.