Abstract
BackgroundA study was carried out to evaluate the response of different native sheep breeds to experimental infection with Anaplasma ovis, the most prevalent sheep tick-borne pathogen in Apulia (Southern Italy). Thirty-four lambs belonging to a Northern European breed (Suffolk) and two Southern Italian breeds (Comisana and Altamurana) were infected. Eleven clinical as well as haematological parameters were monitored at different temporal resolutions on the same subjects before and after the infection, resulting in a data set of 435 observations. The present work, aiming to further the research, presents the results of a multivariate analysis carried out to identify which parameters out of the eleven considered are the most reliable parameters to be considered as markers of the disease phenotype as well as prognosticators of practical clinical importance.ResultsData were analysed by discriminant analysis. Out of the eleven considered variables (red blood cells, packed cell volume, mean corpuscular volume, mean corpuscular haemoglobin, mean corpuscular haemoglobin content, haemoglobin concentration, white blood cells, neutrophils, leukocytes, platelets, rectal temperature), only seven were included in the step-wise model since significantly increasing the Mahlanobis distance between the two closest groups. Both discriminant functions resulted to be highly significant (P < 0.0001) and the percentage of variation accounted for by the first discriminant function was 63.6% of the variance in the grouping variable.ConclusionsTaken together, the observed results stress the marked differentiation among the three breeds in terms of physio-pathological phenotypes indicating packed cell volume and red blood cell count as the most informative parameters in the routine clinical practice for A. ovis infection in sheep.
Highlights
A study was carried out to evaluate the response of different native sheep breeds to experimental infection with Anaplasma ovis, the most prevalent sheep tick-borne pathogen in Apulia (Southern Italy)
Is characterized by a complex orography, a wide extension in latitude and a rich history of genetic mixing with animals brought by migrant or occupying populations through the centuries; as a results, a plethora of native breeds, that have evolved in parallel to their nosological context, can be found [2]. As for the latter aspect, a relevant differentiation between Northern and Southern Italy is represented by tick-borne diseases (TBDs), which are enzootic only in the southern part of the peninsula
Based on the above considerations, a study was carried out [8] to evaluate the response of sheep breeds native both from Southern Italy (Comisana and Altamurana) and Northern Europe (Suffolk) through an experimental infection with Anaplasma ovis, an obligate intraerythrocytic Rickettsia, the most prevalent sheep tick-borne pathogen (TBP) in Apulia (Southern Italy) [9]
Summary
A study was carried out to evaluate the response of different native sheep breeds to experimental infection with Anaplasma ovis, the most prevalent sheep tick-borne pathogen in Apulia (Southern Italy). Breeds traditionally reared below the 41° parallel generally display a good tolerance to TBDs [3] Due to this feature, breeds from these areas are of particular interest to better understand the phenotype “tolerance to TBDs”, which is known to be under complex multi-factorial regulation [4,5] and possibly not unrelated to the erythropoietic system [3] as well as to the haemoglobin genetic systems [6,7]. Based on the above considerations, a study was carried out [8] to evaluate the response of sheep breeds native both from Southern Italy (Comisana and Altamurana) and Northern Europe (Suffolk) through an experimental infection with Anaplasma ovis, an obligate intraerythrocytic Rickettsia, the most prevalent sheep tick-borne pathogen (TBP) in Apulia (Southern Italy) [9]
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
