Screening for several potential pathogens in feral pigeons ( Columba livia ) in Madrid

Table 3 Prevalence of the three pathogens analyzed in the feral pigeon population in Madrid, sampled at three different times.

Sampling time	*Chlamydophila psittaci*	*Campylobacter jejuni*	*Campylobacter coli*
Nov. 2006	59.7%^a (37/62)	81.8%^b (36/44)	0% (0/44)
May 2007	37.0%^a (10/27)	86.4%^b (19/22)	4.5% (1/22)
Nov. 2007	51.8%^a (14/27)	35.7%^b (10/28)	0% (0/28)
*Overall*	*52.6% (61/116)*	*69.1% (65/94)*	*1.1% (1/94)*

Presence of the pathogens was determined by PCR analysis and sequence alignments with Genbank (see Methods).
^a Statistically significant differences among sampling time for Chlamydophila psittaci: November 2006- May 2007 (p = 0.030); May 2007- November 2007 (p = 0.049); November (2006-2007)- May 2007 (0.047).
^b Statistically significant differences among sampling time for Campylobacter jejuni: November 2006- May 2007 (p = 0.032); May 2007- November 2007 (p = 0.001); November 2006- November 2007 (p = 0.001); November (2006-2007)- May 2007 (0.001).