Assessment of anticoccidial efficacy of novel Triazine compound and Sulfaclozine against experimentally induced caecal coccidiosis in broiler chickens

This study was performed to investigate the theraputic efficacy of toltrazuril, sulfaclozine sodium and their combination in broiler chicken for the treatment of experimentally induced caecal coccidiosis. For this purpose, seventy-five day-old chicks were randomly divided into five equal groups (15 each). G1 , kept as control negative; G2 , infected non treated (control positive); G3 , infected treated with toltrazuril (1 mL/L); G4 , infected treated with sodium sulfaclozine (2 mL/L); G5 , infected treated with toltrazuril (1 mL/L) + sulfaclozine Na (2 g/L). All groups except negative control group were inoculated orally with 5 × 104 sporulated oocysts of Eimeria tenella (field isolate) on the day 15th of age. According to the present results, G2 showed a significant increase in oocyst count, AST, ALT, ALP, uric acid, and creatinine, with significant decrease in body weight gain, hematological parameters, total protein, and albumin. Treatment decreased the harmful effect of infection but some significant differences were shown between infected and treated groups and non infected and non treated group in assessment criteria. Furthermore, the histopathological findings were also discussed. In conclusion, the current study showed that the application of both tested drugs gave significant and satisfactory improvement in the assessment criteria as well as they are effective in control of coccidiosis caused by Eimeria tenella

A longitudinal study of Middle East respiratory syndrome coronavirus (MERS-CoV) in dromedary camels

Abstract Background Middle East respiratory syndrome coronavirus (MERS-CoV) was identified in humans in 2012. Since then, 2605 cases and 937 associated deaths have been reported globally. Camels are the natural host for MERS-CoV and camel to human transmission has been documented. The relationship between MERS-CoV shedding and presence of neutralizing antibodies in camels is critical to inform surveillance and control, including future deployment of camel vaccines. However, it remains poorly understood. The longitudinal study conducted in a closed camel herd in Egypt between December 2019 and March 2020 helped to characterize the kinetics of MERS-CoV neutralizing antibodies and its relation with viral shedding. Results During the 100-day longitudinal study, 27 out of 54 camels (50%) consistently tested negative for presence of antibodies against MERS-CoV, 19 (35.2%) tested positive and 8 (14.8%) had both, positive and negative test results. Fourteen events that could be interpreted as serological indication of probable infection (two seroconversions and twelve instances of positive camels more than doubling their optical density ratio (OD ratio) in consecutive samples) were identified. Observed times between the identified events provided strong evidence (p = 0.002) against the null hypothesis that they occurred with constant rate during the study, as opposed to clustering at certain points in time. A generalized additive model showed that optical density ratio (OD ratio) is positively associated with being an adult and varies across individual camels and days, peaking at around days 20 and 90 of the study. Despite serological indication of probable virus circulation and intense repeated sampling, none of the tested nasal swab samples were positive for MERS-CoV RNA, suggesting that, if the identified serological responses are the result of virus circulation, the virus may be present in nasal tissue of infected camels during a very narrow time window. Conclusions Longitudinal testing of a closed camel herd with past history of MERS-CoV infection is compatible with the virus continuing to circulate in the herd despite lack of contact with other camels. It is likely that episodes of MERS-CoV infection in camels can take place with minimal presence of the virus in their nasal tissues, which has important implications for future surveillance and control of MERS-CoV in camel herds and prevention of its zoonotic transmission