PhD in Veterinary Sciences for Animal Health and Food Safety

Contacts

Supervisor

Curriculum vitae

Phd thesis

Ph.D. thesis title is "Metabolic Status, Immune Function, and Uterine Health in Postpartum Dairy Cows: A Novel Approach to Uterine Pathology Diagnosis and Treatment"

Summary

Dairy cows face various health challenges during the transition period, particularly in the postpartum weeks, including oxidative stress (OS), immune dysfunction, and changes in the uterine microbiome, leading to conditions like metritis, Clinical Endometritis (CE), and Purulent vaginal discharge (PVD). OS leads to excessive production of reactive oxygen species (ROS). This OS can worsen inflammatory responses. Research on mitochondrial activity and intracellular ROS in dairy cow endometrial cells is limited. Postpartum (pp) diseases involve complex signaling processes, including cytokine production, and neutrophil mobilization. For endometritis diagnosis, transrectal ultrasonography (TUS) is a reliable on-field method. Understanding the uterine microbiota is essential for therapies. The first objective is Metabolic Status: evaluate OS and metabolic disease by blood and assess OS by endometrial cells using biomarkers in metritis, CE and healthy cows. Second objective is Immune Function: analyze cytokines by blood in metritis and healthy cows and examine neutrophils viability and functionality in healthy cows. Third objective is Uterine health: Diagnose CE by TUS and study uterine microbiota in cows with PVD and CE before and after local antibiotic treatment. For Metabolic Status: The study involved 121 Holstein cows, and blood samples were collected weekly from 7 to 35 days pp to assess OS and metabolic disease. OS markers are reactive oxygen metabolites (d-ROM), antioxidants (OXY), and OS index (OSI). Metabolic disease markers are Glycemia and BHBA. A subset of 6 healthy and 6 metritis cows had endometrial samples collected for mitochondrial activity, intracellular ROS levels, and cell nuclear area assessment. Cows with metritis and CE exhibited higher OS levels compared to healthy cows (P<0.05). However, mitochondrial activity and intracellular ROS levels did not differ between metritis and healthy cows (P>0.05), whereas cell nuclear area showed difference(P<0.05). We found a modest increase in blood glucose in healthy compared to metritis cows at 14 days pp (P<0.05). There was no significant difference in blood glucose and BHBA in CE cows(P>0.05). For immune function evaluation, 25 cows blood samples were collected weekly from 7 to 35 days pp to measure cytokines (TNF-α, IL-6, and IL-10) using ELISA kits. Neutrophil viability and functionality were assessed using flow cytometry with blood samples collected from five cows at multiple time points. Metritis cows showed higher levels of IL-10 compared to healthy cows (P<0.05). For Neutrophil viability, viable PMN showed difference at 0 h and after 6 h of storage (P<0.01). Phagocytosis and Oxidative burst were not different at any time point (P>0.05). For uterine health analysis, TUS was used for CE diagnosis in 93 cows, and uterine microbiota samples were collected from 16 cows. TUS showed higher specificity at 28 and 35 days pp. For uterine microbiota, Trueperella was predominant in cows with PVD and CE, when grown in culture media (P<0.05). Alpha and beta diversities showed a different uterine microbiome in PVD, or CE compared to healthy or healed (P<0.05). At the phylum level, the relative abundance of Bacteroidetes and Fusobacteria was greater in PVD and CE than in healthy or healed cows (P<0.05).

In conclusion, this study demonstrates that dairy cows experiencing metritis and CE exhibit higher levels of oxidative stress and immune imbalances, highlighting the importance of early detection through uterine health assessments for improved management and therapeutic interventions.

Research activities

Research products:

1. Paper related to the Ph.D. project
   • Chandrappa, S.M., Pascottini, O.B., Opsomer, G., Meineri, G., Martino, N.A., Banchi, P., Vincenti, L. and Ricci, A., 2023. Circulating and endometrial cell oxidative stress in dairy cows diagnosed with metritis. Theriogenology, 198, pp.217-223. Impact factor - 2.92, Q1 journal.
2. Paper not related to the Ph.D. project
   • Gonzalez Andueza, S., Azari‐Dolatabad, N., Benedetti, C., Fernandez, A., Angel‐Velez, D., Sadeghi, H., Chandrappa, S.M., Opsomer, G., Van Soom, A. and Pascottini, O.B., 2022. Lycopene supplementation to serum‐free embryo culture medium and its effect on development and quality of bovine blastocysts produced in vitro. Reproduction in Domestic Animals, 57(10), pp.1277-1279. Impact factor - 1.85, Q2 journal.
3. Abstracts of National congresses
   • Chandrappa, S. M.; Martino N.A.; Drago S.; Starvaggi Cucuzza A.; Banchi P.; Vincenti L.; Ricci A. Effect of uterine pathologies, treatments, and β-Hydroxybutyrate on recovering time fertility in dairy cows. 74th Annual SISVET conference (Societa Italiana delle Scienze Veterinarie) in Italy from June 23rd to June 26th, 2021, (Oral presentation).
   • Chandrappa S. M.; Donato G.; Alkhawagah A.; Meineri G.; Vincenti L.; Ricci A. 2022. Evaluation of the effect of oxidative stress on uterine pathologies in postpartum dairy cows. 75th Annual SISVET conference in Italy from June 15th to 19th 2022, in presence. Received Best Poster Award 2022. (Poster presentation).
4. Abstracts of International congresses
   • Chandrappa, S.M.; Bogado Pascottini O.; Meineri G.; Martino N.A.; Banchi P.; Starvaggi Cucuzza A.; Vincenti L.; Ricci A. Evaluation of the effect of oxidative stress in blood serum and endometrial cells in cows with metritis. 24th Annual ESDAR (European Society for Domestic Animal Reproduction) Conference 2021 from 12th to 17th October 2021,(Poster presentation).
   • Ricci A.; Chandrappa S. M.; Gaudino T.; Martino N.A.; Starvaggi Cucuzza A.; Vincenti L. 2020. Transrectal ultrasound as a tool for the diagnosis of clinical endometritis in dairy cows. 24th Annual ESDAR Conference 2021 from 12th to 17th October 2021,(Poster presentation).
   • Chandrappa S. M.; Bogado Pascottini O.; Opsomer G.; Meineri G.; Bergagna S.; Vincenti L.; Ricci A. 2022. Evaluation of oxidative stress and peripheral concentrations of inflammatory cytokines in dairy cows with postpartum metritis. 19th International Congress on Animal Reproduction (ICAR) in Bologna (ITALY) from 27th June to 1st July 2022,(Poster presentation).
   • Chandrappa S. M.; Bogado Pascottini O.; Gonzalez Andueza S.; Sadeghi H.; Vincenti L.; Ricci A.; Opsomer G.; Effect of type of anticoagulant, transportation time, and glucose supplementation to the culture medium on circulating neutrophil viability and functionality in dairy cattle. 31st World Buiatrics Congress (WBC) 2022 Madrid, Spain from September 4th to 8th 2022, (Poster presentation).
   • Chandrappa S. M.; Bogado Pascottini O.; Opsomer G.; Grego. E.; Ala U.; Banchi P.; Vincenti L.; Ricci A. 2022. Uterine microbiota in postpartum dairy cows suffering from purulent vaginal discharge and clinical endometritis prior to and following local antibiotic treatment. 25th Annual ESDAR Conference 2022 from 28th September to 2nd October 2022,(Poster presentation).
   • Chandrappa S. M.; Meineri G.; Vincenti L.; Ricci A. 2023. Clinical approach to clinical endometritis based on Oxidative stress markers and Transrectal ultrasound diagnosis. 1st European Symposium on Animal Reproduction (ESAR) in Nantes, France from 21st to 23rd September 2023, (Poster presentation).
5. Third mission activities  

• Game of Research – North edition, 2021- 16^th December 2021 - Evaluation of the effect of oxidative stress in blood serum and endometrial cells in cows with metritis, (Oral presentation).