Seroprevalence of Leptospira Hardjo in the Irish suckler cattle population

Abstract

BackgroundPrior to the present study, the seroprevalence of leptospirosis in Irish suckler herds was unknown. In this study, we describe the herd and animal-level prevalence of Leptospira Hardjo infection in the Irish suckler cattle population. For the purposes of the study, the 26 counties of the Republic of Ireland were divided into 6 regions from which a representative number of herds were selected. A herd was considered eligible for sampling if it was not vaccinating against leptospirosis and if it contained ≥ 9 breeding animals of beef breed ≥ 12 months of age. In total, 288 randomly selected herds were eligible for inclusion in the seroprevalence dataset analysis. Serological testing was carried out using a commercially available monoclonal antibody-capture ELISA, (sensitivity 100%; specificity 86.67%).ResultsHerds were categorised as either “Free from Infection” or “Infected” using the epidemiological software tool, FreeCalc 2.0. Using this classification, 237 herds were “Infected” (82.29%). The South West and South East regions had the highest herd prevalence. The regional effect on herd prevalence was largely mirrored by breeding herd size. A true animal-level prevalence of 41.75% was calculated using the epidemiological software tool, TruePrev. There was a statistically significant regional trend, with true prevalence being highest in the South East (P < 0.05). The median Breeding Herd Size (BHS), when categorised into quartiles, had a statistically significant influence on individual animal true seroprevalence (P < 0.001); true seroprevalence increased with increasing BHS.ConclusionsLeptospirosis is a widespread endemic disease in the Republic of Ireland. It is possible that economic losses due to leptospirosis in unvaccinated Irish suckler herds may be underestimated.

Herd-level prevalence of selected endemic infectious diseases of dairy cows in Great Britain

“…Regional variations in prevalence of some of the studied pathogens have been reported previously (Ryan et al, 2012;Howell et al, 2015;Sayers et al, 2015). Overall, we found a lower proportion of positive herds in southeast England, where cattle density is lower (<10 dairy cows per 100 ha of farmed land) compared with the other studied regions (CHAWG, 2012).…”

“…Similarly, the prevalence of MAP can be underestimated due to the susceptibility of cows infected with MAP to secondary conditions (e.g., mastitis or lameness; Villarino and Jordan, 2005) and the subsequent exclusion of cows treated with antibiotics from milk sampling and testing. Furthermore, exclusion of the vaccinated herds from the study population resulted in lower precision of the prevalence estimates, such that the smallest number of the studied unvaccinated herds (102 herds) was sufficient to estimate 50% prevalence (the worst-case scenario) with 10% precision and 95% confidence.Regional variations in prevalence of some of the studied pathogens have been reported previously (Ryan et al, 2012;Howell et al, 2015;Sayers et al, 2015). Overall, we found a lower proportion of positive herds in southeast England, where cattle density is lower (<10 dairy cows per 100 ha of farmed land) compared with the other studied regions (CHAWG, 2012).…”

Serosurvey for Zoonotic Viral and Bacterial Pathogens Among Slaughtered Livestock in Egypt

“…is not performed among ruminants in Egypt, it is likely that livestock demonstrating antibodies against Leptospira spp. have been naturally infected with the bacteria except for the 19 antibody-positive buffalo less than 6 months of age, which may carry maternal antibodies at this age (Ryan et al 2012). …”

Presence of Antibodies Against Leptospira interrogans Serovar hardjo in Serum Samples from Cattle in Ukraine

“…Different species of animals are hosts for various serovars of Leptospira. Thus, cattle are maintenance host for serovar hardjo (Ellis et al 1981;Ryan et al 2012) but the scientific literature from different countries describes cases of infection by this pathogen in other species too (red deer in Italy, brown bears in Croatia, wild boars in Poland, etc.) (Slavica et al 2010;Andreoli et al 2014;Żmudzki et al 2015).…”

“…The highest risk is asso ciated with dairy farming and is linked mainly to serovar hardjo (Levett 2001). Nowadays, cattle are the maintenance hosts for this serovar (Ellis et al 1981;Ryan et al 2012), and shed leptospires both in urine and the discharges from the genital tract (Ryan et al 2012). The infection with this pathogen occurs worldwide: in Malaysia, Argentina, Chile, India, and the European countries (Myers and Jelambi 1975;Bahaman et al 1988;Sehgal 2000;Salgado et al 2015).…”