# Serological Investigation and Epidemiological Analysis of Bovine Leptospirosis in Egypt
## 4 Discussion
However, other previous research in Egypt recorded slightly higher seroprevalence rates (44%) of leptospirosis in nine cattle from Mahalla City, Gharbeya Governorate, Egypt using MAT [9]. The same previous study [9] explored the cross-species surveillance of _Leptospira_ in animals to discover the most common serovars in the studied area region, reflecting that wild and domestic mammals are key sources of pathogenic _Leptospira_. As mentioned previously, very limited studies have explored the status of leptospirosis from the same province [25; 26]. In stark contrast to our present findings, a previous study [25] that examined a total of 97 urine samples from suspected cattle revealed a prevalence rate of 28.9% (28/97) and 45.4% (44/97) for leptospirosis among examined cattle using Dark Field Microscopy and staining via Silver Impregnation Methods, respectively. Another previous study [26] revealed a lower prevalence rate of 4.8% for _Leptospira interrogans_ serogroup Icterohemorhagia serovar Icterohemorhagia among a total number of 353 serum samples from cattle in Dakahilia province using the complement fixation test. Likewise, another study in cows from Kafrelsheikh governorate, Egypt, reported very low seroprevalence (3.6%) of leptospirosis caused by _L. interrogans_ serogroup Hardjo serovar Hardjo using ELISA [41]. Furthermore, a recent outbreak of leptospirosis in a total of 45 sheep had been reported in a previous study [42], which had been the first epidemic in northern Egypt. Contrary to the results of the current study, very high prevalence of bovine leptospirosis had been previously reported in other countries, including India (87.0%) [43] and Poland (89.9%) [44]. This difference in leptospirosis prevalence rates between our study and those mentioned earlier might have been attributed to multiple factors, including geographic location, climatic conditions, sample size, the performed serological test and its sensitivity, abundance of rodents, herd management, and animal density considering that the presence of a dense population of cattle infected with _Leptospira_ spp. may contribute to environmental contamination and dissemination of infection [4; 45; 46]. It is therefore unsurprising to suggest that the transmission dynamics of the disease is exceedingly complex and variable and seems to be associated with environmental conditions [45; 46]. Interestingly, the present study investigated multiple individual variable factors, including locality, age, sex, and reported clinical signs and their potential association with infection occurrence. Regarding locality, the prevalence rate of leptospirosis was significantly higher (11.33%) in cattle of stakeholders from Dikirnis and Belkas districts compared to those from Mansoura (8.67%) and Sherbin districts (8%). The present findings are consistent with several previous studies, which hypothesized that leptospirosis was highly associated with exposure to rice fields and contaminated surface water [47; 41]. However, this difference among studied localities might have been due to variations in agricultural practices and the fact that animals from Dikirnis and Belkas districts usually drink from surface water channels used for land irrigation. In addition, several rice fields are present in the governorate, whereas animals from Mansoura and Sherbin used tape water (treated) for drinking. Regarding the four age groups studied, Table 3 revealed that the prevalence rate was significantly higher in cattle aged 3-5 years (22%, 132/600), followed by those aged 1-3 years (8.67%, 52/600), with those below 1 year old showing a lower prevalence rate (2.66%, 16/600). This result is consistent with several previous studies [4; 48; 49] that found higher prevalence rates among cattle in the 3- to 5-year age group compared to other age groups. Previous research revealed that leptospirosis seroprevalence, using ELISA, in cattle gradually increased with the age of the animals [39].