Volume 63 (2013) Issue: 2013 No#1

SEROEPIDEMIOLOGICAL DETECTION OF ANTIBODIES AGAINST LEPTOSPIRA spp USING MICROSCOPIC AGGLUTINATION TEST IN URMIA COWS AND SHEEP

Author(s): Ramin AG, Azizzadeh F

Keywords:cows, grippotyphosa, Leptospirosis, serology, sheep, MAT, pomona

The study was designed to determine the level of incidence, titer and various serovars of leptospira in 203 cows and 166 sheep at Urmia abattoir in 2011. Blood samples were collected during the slaughter of animals and sera were separated to evaluate the serological reaction to Leptospira spp by Microscopic Agglutination Test (MAT) using live antigens representing Leptospira interrogans serogroups: pomona, grippotyphosa, canicola, hardjo, icterrohaemoragiae, and ballum. Overall, 36% of cows and 19.3% of sheep including 33.8% of bulls, 40.5% of female cows, 18.3% of rams and 25% of ewes had a positive reaction to at least one of the leptospira serovars. The most prevalent serovars in cows were pomona (22.7%), grippotyphosa (13.8%), and hardjo (8.4%), and in sheep were grippotyphosa (66.7%), pomona (26.2%) and canicola (7.1%). Other serovars were not detected in cows and sheep. The most prevalent serological titers of 1:100 and 1:200 in cows was 18.2% and 26.6%, and for sheep were 13.5% and 8%, respectively, and of 1:400 in sheep was 2.3%. Cows with a positive reaction to one, two and three serovars were 28.6%, 5.9%, and 1.5% and sheep positive to one and two serovars were 13.3% and 6%, respectively. Age comparison in seropositive cows and sheep showed a significantly increased infection (p<0.05) from young to adult ruminants, while no differences were seen regarding gender. The main mixed serovars were between grippotyphosa/pomona, grippotyphosa/canicola and canicola/pomona. The gender comparison of the serovars' distribution revealed that the pomona and grippotyphosa were predominant among other leptospiral serovars in cows and sheep, respectively. In conclusion, the rate of leptospirosis in Urmia cows was about 2 fold in sheep. The most current serovars in cows and sheep were pomona and grippotyphosa, respectively. The majority of animals was infected with one serovar, but polyserovars, are also possible. The highest titer (1:200) was observed in cows and 1:400 in sheep. There was no gender difference, but age was significant between cows and sheep. Finally, leptospirosis as a zoonotic disease must be seriously considered in Urmia cows rather than in sheep, and therefore, a serious effort must be made to reduce the rate of serological infection and the risk of public health, as well.