@article{khaled_gaghan_fares_goodell_stanley_kulkarni_gimeno_2025, title={Protection Conferred by Gallid Alphaherpesvirus 2 Vaccines Against Immunosuppression Induced by Very Virulent Plus (vv+) Marek's Disease Virus Strains in Commercial Meat Type Chickens}, volume={14}, ISSN={["2076-0817"]}, url={https://doi.org/10.3390/pathogens14010054}, DOI={10.3390/pathogens14010054}, abstractNote={Very virulent plus Marek’s disease virus (vv+MDV) induces severe immunosuppression in commercial chickens. In this study, we evaluated how three Gallid alphaherpesvirus 2 (GaHV-2) vaccines (CVI-988, rMd5-BAC∆Meq, and CVI-LTR) protected against two negative outcomes of vv+MDV infection: (1) reduced viability and frequency of immune cells in the spleen and (2) decreased efficacy of the CEO (chicken embryo origin) vaccine against infectious laryngotracheitis challenge. At 25 days post-infection with vv+MDV 686, all vaccines are protected against the reduced viability of splenocytes. However, there were differences in the frequency of splenic immunophenotypes among groups. Compared to the uninfected control, the frequency of B cells was reduced in the CVI-988/686 group but not in the rMd5-BAC∆Meq/686 and CVI-LTR/686 groups. T cell subset frequencies showed no difference between the negative controls and CVI-988/686; however, there was a reduction in activated CD4+ T cells in the rMd5-BAC∆Meq/686 group and in activated CD4+, activated CD8+, and γδ+ T cells in the CVI-LTR/686 group. We also demonstrated that the three vaccines protected against MDV-induced tumors, but only rMd5-BAC∆Meq and CVI-LTR protected against the negative impact of vv+MDV 648A strain on CEO vaccine efficacy. Our findings demonstrate important differences in the biology and/or mechanisms of protection of these vaccines.}, number={1}, journal={PATHOGENS}, author={Khaled, Nagwa and Gaghan, Carissa and Fares, Abdelhamid M. and Goodell, Christa and Stanley, William and Kulkarni, Raveendra R. and Gimeno, Isabel M.}, year={2025}, month={Jan} }
 @article{criollo_john_gaghan_fletcher_thachil_crespo_kulkarni_2024, title={Characterization of immune responses and immunopathology in turkeys experimentally infected with clostridial dermatitis-producing strains of Clostridium septicum}, volume={269}, ISSN={["1873-2534"]}, DOI={10.1016/j.vetimm.2024.110717}, abstractNote={Clostridium septicum is one of the major causative agents of clostridial dermatitis (CD), an emerging disease of turkeys, characterized by sudden deaths and necrotic dermatitis. Despite its economic burden on the poultry industry, the immunopathological changes and pathogen-specific immune responses are poorly characterized. Here, we used three strains of C. septicum, namely Str. A1, Str. B1 and Str. C1, isolated from CD field outbreaks, to experimentally infect turkeys to evaluate local (skin and muscle) and systemic (spleen) pathological and immunological responses. Results showed that while all three strains produced an acute disease, Str. A1 and B1 caused significantly higher mortality when compared to Str. C1. Gross and histopathology evaluation showed that birds infected with Str. A1 and B1 had severe inflammatory, edematous, granulomatous and necrotic lesions in the skin, muscle and spleen, while these lesions produced by Str. C1 were relatively less severe and mostly confined to skin and/or muscle. Immune gene expression in these tissues showed that Str. B1-infected birds had significantly higher expression of interleukin (IL)−1β, IL-6 and interferon (IFN)γ genes compared to uninfected control, suggesting a robust inflammatory response both locally as well as systemically. The transcription of IL-1β and IFNγ in the muscle or spleen of Str. A1-infected birds and IL-1β in the skin of Str. C1-infected group was also significantly higher than control. Additionally, Str. A1 or B1-infected groups also had significantly higher IL-4 transcription in these tissues, while birds infected with all three strains developed C. septicum-specific serum antibodies. Furthermore, splenic cellular immunophenotyping in the infected turkeys showed a marked reduction in CD4+ cells. Collectively, it can be inferred that host responses against C. septicum involve an acute inflammatory response along with antibody production and that the disease severity seem to depend on the strain of C. septicum involved in CD in turkeys.}, journal={VETERINARY IMMUNOLOGY AND IMMUNOPATHOLOGY}, author={Criollo, Valeria and John, Feba Ann and Gaghan, Carissa and Fletcher, Oscar J. and Thachil, Anil and Crespo, Rocio and Kulkarni, Raveendra R.}, year={2024}, month={Mar} }
 @article{boone_kulkarni_cortes_gaghan_mohammed_villalobos_esandi_gimeno_2024, title={Evaluation of Adjuvant Effect of Cytosine-Guanosine-Oligodeoxynucleotide in Meat-Type Chickens Coadministered <i>In Ovo</i> with Herpesvirus of Turkey Vaccine}, volume={2}, ISSN={["1557-8976"]}, url={https://doi.org/10.1089/vim.2023.0125}, DOI={10.1089/vim.2023.0125}, abstractNote={Herpesvirus of turkey (HVT) increases activation of T cells in 1-day-old chickens when administered}, journal={VIRAL IMMUNOLOGY}, author={Boone, Allison C. and Kulkarni, Raveendra R. and Cortes, Aneg L. and Gaghan, Carissa and Mohammed, Javid and Villalobos, Tarsicio and Esandi, Javier and Gimeno, Isabel M.}, year={2024}, month={Feb} }
 @article{john_criollo_gaghan_armwood_holmes_thachil_crespo_kulkarni_2024, title={Immunization of turkeys with <i>Clostridium septicum</i> alpha toxin-based recombinant subunit proteins can confer protection against experimental Clostridial dermatitis}, volume={19}, ISSN={["1932-6203"]}, url={https://doi.org/10.1371/journal.pone.0302555}, DOI={10.1371/journal.pone.0302555}, abstractNote={Clostridial dermatitis (CD), caused by Clostridium septicum , is an emerging disease of increasing economic importance in turkeys. Currently, there are no effective vaccines for CD control. Here, two non-toxic domains of C . septicum alpha toxin, namely ntATX-D1 and ntATX-D2, were identified, cloned, and expressed in Escherichia coli as recombinant subunit proteins to investigate their use as potential vaccine candidates. Experimental groups consisted of a Negative control (NCx) that did not receive C . septicum challenge, while the adjuvant-only Positive control (PCx), ntATX-D1 immunization (D1) and ntATX-D2 immunization (D2) groups received C . septicum challenge. Turkeys were immunized subcutaneously with 100 μg of protein at 7, 8 and 9 weeks of age along with an oil-in-water nano-emulsion adjuvant, followed by C . septicum challenge at 11 weeks of age. Results showed that while 46.2% of birds in the PCx group died post-challenge, the rate of mortality in D1- or D2-immunization groups was 13.3%. The gross and histopathological lesions in the skin, muscle and spleen showed that the disease severity was highest in PCx group, while the D2-immunized birds had significantly lower lesion scores when compared to PCx. Gene expression analysis revealed that PCx birds had significantly higher expression of pro-inflammatory cytokine genes in the skin, muscle and spleen than the NCx group, while the D2 group had significantly lower expression of these genes compared to PCx. Peripheral blood cellular analysis showed increased frequencies of activated CD4+ and/or CD8+ cells in the D1 and D2-immunized groups. Additionally, the immunized turkeys developed antigen-specific serum IgY antibodies. Collectively, these findings indicate that ntATX proteins, specifically the ntATX-D2 can be a promising vaccine candidate for protecting turkeys against CD and that the protection mechanisms may include downregulation of C . septicum -induced inflammation and increased CD4+ and CD8+ cellular activation.}, number={4}, journal={PLOS ONE}, author={John, Feba Ann and Criollo, Valeria and Gaghan, Carissa and Armwood, Abigail and Holmes, Jennifer and Thachil, Anil J. and Crespo, Rocio and Kulkarni, Raveendra R.}, editor={Chang, Yung-FuEditor}, year={2024}, month={Apr} }
 @article{john_gaghan_liu_wolfenden_kulkarni_2024, title={Screening and selection of eubiotic compounds possessing immunomodulatory and anti-Clostridium perfringens properties}, volume={103}, ISSN={["1525-3171"]}, url={https://doi.org/10.1016/j.psj.2024.103911}, DOI={10.1016/j.psj.2024.103911}, abstractNote={Eubiotics are water and/or feed additives used in poultry to promote gut health and control enteric burden of pathogens, including Clostridium perfringens. While several eubiotic compounds (ECs) are being introduced commercially, it is essential to devise an in vitro model to screen these compounds to assess their immunomodulatory and antimicrobial properties prior to their testing in vivo. A chicken macrophage cell-line (MQ-NCSU) was used to develop an in vitro model to screen the immunological and anti-C. perfringens properties of 10 ECs: monobutyrin, monolaurin, calcium butyrate, tributyrin, carvacrol, curcumin, green tea extract, rosemary extract, monomyristate, and tartaric acid. An optimal concentration for each EC was selected by measuring the effect on viability of MQ-NCSU cells. Cells were then treated with ECs for 6, 12, and 24 h. and expression of interferon-gamma (IFNγ), interleukin (IL)-1β, IL-6, IL-10, transforming growth factor-beta (TGFβ) and cluster of differentiation (CD40) genes, as well as major histocompatibility complex (MHC)-II protein were evaluated. At 6 h post-stimulation, monobutyrin, calcium butyrate, and green tea extract treatments induced a significant downregulation of IFNγ, IL-6, or IL-1β gene transcription and MHC-II expression, while the IL-10 or TGFβ gene expression in these treatments as well as those receiving rosemary extract and tartaric acid was significantly upregulated, when compared to control, suggesting immunomodulatory properties of these ECs. Finally, pretreatment of macrophages with these selected 5 ECs for 24 h followed by C. perfringens infection showed that monobutyrin, green tea extract, rosemary extract, and calcium butyrate treatments can inhibit bacterial growth significantly at 12 and/or 24 h post-infection, when compared to the control. Collectively, our findings show that ECs possessing immunomodulatory and anti-C. perfringens properties can be selected using an in vitro avian macrophage cell-based model so that such ECs can further be tested in vivo for their disease prevention efficacy.}, number={8}, journal={POULTRY SCIENCE}, author={John, Feba Ann and Gaghan, Carissa and Liu, Jundi and Wolfenden, Ross and Kulkarni, Raveendra R.}, year={2024}, month={Aug} }
 @article{gaghan_browning_cortes_gimeno_kulkarni_2023, title={Effect of CpG-Oligonucleotide in Enhancing Recombinant Herpes Virus of Turkey-Laryngotracheitis Vaccine-Induced Immune Responses in One-Day-Old Broiler Chickens}, volume={11}, ISSN={["2076-393X"]}, url={https://doi.org/10.3390/vaccines11020294}, DOI={10.3390/vaccines11020294}, abstractNote={Infectious laryngotracheitis (ILT) is an economically important disease of chickens. While the recombinant vaccines can reduce clinical disease severity, the associated drawbacks are poor immunogenicity and delayed onset of immunity. Here, we used CpG-oligonucleotides (ODN) as an in ovo adjuvant in boosting recombinant herpesvirus of turkey-laryngotracheitis (rHVT-LT) vaccine-induced responses in one-day-old broiler chickens. Two CpG-ODN doses (5 and 10 μg/egg) with no adverse effect on the vaccine-virus replication or chick hatchability were selected for immune-response evaluation. Results showed that while CpG-ODN adjuvantation induced an increased transcription of splenic IFNγ and IL-1β, and lung IFNγ genes, the IL-1β gene expression in the lung was significantly downregulated compared to the control. Additionally, the transcription of toll-like receptor (TLR)21 in the spleen and lung and inducible nitric oxide synthase (iNOS) in the spleen of all vaccinated groups was significantly reduced. Furthermore, splenic cellular immunophenotyping showed that the CpG-ODN-10μg adjuvanted vaccination induced a significantly higher number of macrophages, TCRγδ+, and CD4+ T cells as well as a higher frequency of activated T cells (CD4+CD44+) when compared to the control. Collectively, the findings suggested that CpG-ODN can boost rHVT-LT-induced immune responses in day-old chicks, which may help in anti-ILT defense during their later stages of life.}, number={2}, journal={VACCINES}, author={Gaghan, Carissa and Browning, Matthew and Cortes, Aneg L. and Gimeno, Isabel M. and Kulkarni, Raveendra R.}, year={2023}, month={Feb} }
 @article{criollo_gaghan_john_orozco_thachil_crespo_kulkarni_2023, title={Immune Response Evaluation in Commercial Turkeys Affected with Clostridial Dermatitis}, volume={67}, ISSN={["1938-4351"]}, DOI={10.1637/aviandiseases-D-22-00089}, abstractNote={Evaluación de la respuesta inmune en pavos comerciales afectados por dermatitis clostridial. La dermatitis clostridial (CD), causada por Clostridium septicum y Clostridium perfringens, es una enfermedad emergente económicamente importante de los pavos caracterizada por muerte súbitas y dermatitis necrótica. Se conoce poco acerca de las respuestas inmunitarias en pavos comerciales afectados por dermatitis clostridial. En el presente estudio, se aisló C. septicum de pavos comerciales afectados por dermatitis clostridial durante un brote reciente, y los tejidos (piel, músculo y bazo) se recolectaron y analizaron para determinar la expresión de genes inmunitarios junto con muestras de aves clínicamente sanas. Los resultados mostraron que los pavos afectados por dermatitis clostridial tenían niveles significativamente más altos de transcritos de IL-1β, IL-6, IFNγ, and iNOS en los tejidos de la piel, los músculos y el bazo en comparación con las aves sanas. Los pavos afectados también tenían una transcripción significativamente elevada del gene del receptor tipo toll (TLR21) en los tejidos de la piel y el bazo, lo que sugiere un papel de este receptor en el reconocimiento inmunitario. La expresión de los genes IL-4 e IL-13 en el bazo y el músculo también fue significativamente mayor en las aves afectadas. Aves adicionales de las mismas granjas afectadas y sanas que fueron examinadas por serología revelaron que los pavos afectados por dermatitis clostridial tenían niveles significativamente más altos de anticuerpos séricos IgM e IgY. Además, la estimulación in vitro de los macrófagos MQ-NCSU con C. septicum condujo a una regulación transcripcional significativamente al alza de los genes IL-1β and IFNγ, mientras que la expresión del gene IL-10 se reguló a la baja. La expresión superficial de la proteína MHC-II y la producción celular de óxido nítrico también aumentaron significativamente en los macrófagos estimulados por C. septicum, lo que indica activación celular. Colectivamente, estos hallazgos sugieren que las respuestas del huésped en pavos afectados por dermatitis clostridial implican una respuesta inflamatoria robusta, así como una respuesta mediada por citoquinas IL4/IL-13 que pueden ayudar en la inmunidad mediada por anticuerpos.}, number={1}, journal={AVIAN DISEASES}, author={Criollo, Valeria and Gaghan, Carissa and John, Feba and Orozco, Eric and Thachil, Anil and Crespo, Rocio and Kulkarni, Raveendra R.}, year={2023}, month={Mar}, pages={80–88} }
 @article{gaghan_browning_fares_abdul-careem_gimeno_kulkarni_2023, title={In Ovo Vaccination with Recombinant Herpes Virus of the Turkey-Laryngotracheitis Vaccine Adjuvanted with CpG-Oligonucleotide Provides Protection against a Viral Challenge in Broiler Chickens}, volume={15}, ISSN={["1999-4915"]}, url={https://www.mdpi.com/1999-4915/15/10/2103}, DOI={10.3390/v15102103}, abstractNote={Infectious laryngotracheitis (ILT) is an economically important disease in chickens. We previously showed that an in ovo adjuvantation of recombinant herpesvirus of the turkey-Laryngotracheitis (rHVT-LT) vaccine with CpG-oligonucleotides (ODN) can boost vaccine-induced responses in one-day-old broiler chickens. Here, we evaluated the protective efficacy of in ovo administered rHVT-LT + CpG-ODN vaccination against a wild-type ILT virus (ILTV) challenge at 28 days of age and assessed splenic immune gene expression as well as cellular responses. A chicken-embryo-origin (CEO)-ILT vaccine administered in water at 14 days of age was also used as a comparative control for the protection assessment. The results showed that the rHVT-LT + CpG-ODN or the CEO vaccinations provided significant protection against the ILTV challenge and that the level of protection induced by both the vaccines was statistically similar. The protected birds had a significantly upregulated expression of interferon (IFN)γ or interleukin (IL)-12 cytokine genes. Furthermore, the chickens vaccinated with the rHVT-LT + CpG-ODN or CEO vaccine had a significantly higher frequency of γδ T cells and activated CD4+ or CD8+ T cells, compared to the unvaccinated-ILTV challenge control. Collectively, our findings suggest that CpG-ODN can be used as an effective adjuvant for rHVT-LT in ovo vaccination to induce protective immunity against ILT in broiler chickens.}, number={10}, journal={VIRUSES-BASEL}, author={Gaghan, Carissa and Browning, Matthew and Fares, Abdelhamid M. and Abdul-Careem, Mohamed Faizal and Gimeno, Isabel M. and Kulkarni, Raveendra R.}, year={2023}, month={Oct} }
 @article{gaghan_gorrell_taha-abdelaziz_sharif_kulkarni_2023, title={Intracloacal Inoculation of Broiler Chickens with Clostridium perfringens Strains: Evaluation of Necrotic Enteritis Disease Development and Lymphoid Immune Responses}, volume={11}, ISSN={["2076-2607"]}, url={https://doi.org/10.3390/microorganisms11030771}, DOI={10.3390/microorganisms11030771}, abstractNote={Necrotic enteritis (NE) is an economically important disease of chickens. We have recently shown that inflammatory responses in chickens inoculated orally with virulent Clostridium perfringens were spatially regulated. Here, we used previously virulence-characterized netB+ C. perfringens strains, avirulent CP5 and virulent CP18 and CP26, to assess the severity of NE and immune responses in broiler chickens when inoculated intracloacally. The results showed that CP18- and CP26-infected birds had a reduced weight gain and developed milder/less severe NE lesions, as determined by the gross lesions scores, suggesting a subclinical-grade infection. Gene expression analysis in infected birds revealed three statistically significant observations compared to uninfected-control: (1) Increased expression of anti-inflammatory/immunoregulatory interleukin (IL)-10/transforming growth factor (TGF)β in cecal tonsil (CT) and bursa of Fabricius in the CP18/CP26-infected groups. (2) Increased CT transcription of pro-inflammatory IL-1β, IL-6 and interferon (IFN)γ and decreased Harderian gland (HG) expression of IFNγ in the CP18/CP26-infected birds. (3) Increased HG or bursal expression of IL-4 and IL-13 in CP5-infected birds. Collectively, intracloacal C. perfringens inoculation seems to induce a highly regulated inflammatory response in the CT and other mucosal lymphoid organs and an intracloacal infection model may be useful in evaluating immune responses in chickens with subclinical NE.}, number={3}, journal={MICROORGANISMS}, author={Gaghan, Carissa and Gorrell, Kaitlin and Taha-Abdelaziz, Khaled and Sharif, Shayan and Kulkarni, Raveendra R.}, year={2023}, month={Mar} }
 @article{kulkarni_gaghan_gorrell_fletcher_2023, title={Mucosal and systemic lymphoid immune responses against Clostridium perfringens strains with variable virulence in the production of necrotic enteritis in broiler chickens}, volume={1}, ISSN={["1465-3338"]}, DOI={10.1080/03079457.2022.2154195}, abstractNote={Necrotic enteritis (NE), caused by Clostridium perfringens, is an economically important disease of chickens. Although NE pathogenesis is moderately well studied, the host immune responses against C. perfringens are poorly understood. The present study used an experimental NE model to characterize lymphoid immune responses in the caecal tonsils (CT), bursa of Fabricius, Harderian gland (HG) and spleen tissues of broiler chickens infected with four netB+ C. perfringens strains (CP1, CP5, CP18, and CP26), of which CP18 and CP26 strains also carried the tpeL gene. The gross and histopathological lesions in chickens revealed CP5 to be avirulent, while CP1, CP18, and CP26 strains were virulent with CP26 being "very virulent". Gene expression analysis showed that, while the virulent strains induced a significantly upregulated expression of pro-inflammatory IL-1β gene in CT, the CP26-infected birds had significantly higher CT transcription of IFNγ and IL-6 pro-inflammatory genes compared to CP5-infected or uninfected chickens. Furthermore, CP26 infection also led to significantly increased bursal and HG expression of the anti-inflammatory/regulatory genes, IL-10 or TGFβ, compared to control, CP5 and CP1 groups. Additionally, the splenic pro- and anti-inflammatory transcriptional changes were observed only in the CP26-infected chickens. An antibody-mediated response, as characterized by increased IL-4 and/or IL-13 transcription and elevated IgM levels in birds infected with virulent strains, particularly in the CP26-infected group compared to uninfected controls, was also evident. Collectively, our findings suggest that lymphoid immune responses during NE in chickens are spatially regulated such that the inflammatory responses against C. perfringens depend on the virulence of the strain.}, journal={AVIAN PATHOLOGY}, author={Kulkarni, Raveendra R. and Gaghan, Carissa and Gorrell, Kaitlin and Fletcher, Oscar J.}, year={2023}, month={Jan} }
 @article{kulkarni_gaghan_mohammed_2022, title={Avian Macrophage Responses to Virulent and Avirulent Clostridium perfringens}, volume={11}, ISSN={["2076-0817"]}, url={https://doi.org/10.3390/pathogens11010100}, DOI={10.3390/pathogens11010100}, abstractNote={The present study evaluated the avian macrophage responses against Clostridium perfringens that varied in their ability to cause necrotic enteritis in chickens. Strains CP5 (avirulent-netB+), CP1 (virulent-netB+), and CP26 (highly virulent-netB+tpeL+) were used to evaluate their effect on macrophages (MQ-NCSU cells) and primary splenic and cecal tonsil mononuclear cells. The bacilli (whole cells) or their secretory products from all three strains induced a significant increase in the macrophage transcription of Toll-like receptor (TLR)21, TLR2, interleukin (IL)-1β, inducible nitric oxide synthase (iNOS), and CD80 genes as well as their nitric oxide (NO) production and major histocompatibility complex (MHC)-II surface expression compared to an unstimulated control. The CP1 and CP26-induced expression of interferon (IFN)γ, IL-6, CD40 genes, MHC-II upregulation, and NO production was significantly higher than that of CP5 and control groups. Furthermore, splenocytes and cecal tonsillocytes stimulated with bacilli or secretory products from all the strains showed a significant increase in the frequency of macrophages, their surface expression of MHC-II and NO production, while CP26-induced responses were significantly higher for the rest of the groups. In summary, macrophage interaction with C. perfringens can lead to cellular activation and, the ability of this pathogen to induce macrophage responses may depend on its level of virulence.}, number={1}, journal={PATHOGENS}, author={Kulkarni, Raveendra R. and Gaghan, Carissa and Mohammed, Javid}, year={2022}, month={Jan} }
 @article{gaghan_adams_mohammed_crespo_livingston_kulkarni_2022, title={Characterization of vaccine-induced immune responses against coccidiosis in broiler chickens}, volume={40}, ISSN={["1873-2518"]}, url={https://doi.org/10.1016/j.vaccine.2022.05.043}, DOI={10.1016/j.vaccine.2022.05.043}, abstractNote={Coccidiosis, caused by Eimeria protozoan species, is an economically important enteric disease of poultry. Although commercial live vaccines are widely used for disease control, the vaccine-induced protective immune mechanisms are poorly characterized. The present study used a commercial broiler vaccine containing a mixture of E. acervulina, E. maxima, and E. tenella. One-day-old chicks were vaccinated by spray followed by a challenge at 21 days of age with a mixture of wild type Eimeria species via oral gavage. Oocyst shedding, immune gene expression and cellular responses in the spleen and cecal tonsils were measured at pre- (days 14 and 21) and post-challenge (days 24, 28 and 35) time points. Results showed that the oocyst counts were significantly reduced in the vaccinated chickens at post-challenge compared to unvaccinated control group. While the vaccinated birds had a significantly increased toll-like receptor (TLR) 21 gene expression at pre-challenge, the transcription of interferon (IFN)γ, Interleukin (IL)-12 and CD40 genes in spleen and cecal tonsils of these birds was significantly higher at post-challenge compared to unvaccinated chickens. Cellular immunophenotyping analysis found that vaccination led to increased frequency of macrophages and activated T cells (CD8+CD44+ and CD4+CD44+) in the spleen and cecal tonsils at post-challenge. Furthermore, in vitro stimulation of chicken macrophages (MQ-NCSU cells) with purified individual species of E. acervulina, E. maxima, and E. tenella showed a significantly increased expression of TLR21, TLR2 and IFNγ genes as well as nitric oxide production. Collectively, these findings suggest that TLR21 and TLR2 may be involved in the immune cell recognition of Eimeria parasites and that the vaccine can induce a robust macrophage activation leading to a T helper-1 dominated protective response at both local and systemic lymphoid tissues.}, number={29}, journal={VACCINE}, publisher={Elsevier BV}, author={Gaghan, Carissa and Adams, Daniel and Mohammed, Javid and Crespo, Rocio and Livingston, Kimberly and Kulkarni, Raveendra R.}, year={2022}, month={Jun}, pages={3893–3902} }
 @article{boyett_crespo_vinueza_gaghan_mohammed_kulkarni_2022, title={Enumeration and speciation of coccidia affecting turkeys using flow cytometry method}, volume={31}, ISSN={["1537-0437"]}, url={https://doi.org/10.1016/j.japr.2022.100270}, DOI={10.1016/j.japr.2022.100270}, abstractNote={Enumeration of Eimeria oocysts is a common practice in monitoring coccidiosis in turkeys; however, the conventional method of manual microscopic examination of Eimeria oocysts is time-consuming. Previously, we used flow cytometry (FCM) to enumerate and speciate coccidia affecting chickens and here, we extended those findings to turkey coccidia species, E. adenoides and E. meleagrimitis. Using FCM, a commercial vaccine containing these species was used to optimize the scatter-plot parameters, including Forward-(size) and Side-(shape/granularity) scatter Area, Height, and Width patterns for Eimeria. The two Eimeria species populations in the vaccine were accurately phenotyped and the gated populations were then sorted using a Cell sorter instrument to obtain pure oocyst suspensions. The individual Eimeria species identity of sorted oocysts was confirmed by PCR using species-specific primers. A significant (P = 0.0466) correlation (R = 0.9893) in the total oocyst count between FCM and manual methods were observed. Furthermore, when FCM was employed to analyze farm fecal samples, the close similarities in the oocyst morphologies coupled with organic debris particulate interference prevented a precise separation of these 2 species resulting in a lack of oocyst count (OPG) correlation between the 2 methods. The OPG counts by FCM were much lower than the manual method; however, a partial OPG trend between the two methods was observed only at the early timepoint collections during a period of 35 d. Collectively, our findings showed that FCM can be used in the enumeration of turkey Eimeria oocysts with a potential scope for a more precise enumeration and speciation in field samples.}, number={3}, journal={JOURNAL OF APPLIED POULTRY RESEARCH}, publisher={Elsevier BV}, author={Boyett, Taylor and Crespo, Rocio and Vinueza, Valeria C. and Gaghan, Carissa and Mohammed, Javid P. and Kulkarni, Raveendra R.}, year={2022}, month={Sep} }
 @misc{kulkarni_gaghan_gorrell_sharif_taha-abdelaziz_2022, title={Probiotics as Alternatives to Antibiotics for the Prevention and Control of Necrotic Enteritis in Chickens}, volume={11}, ISSN={["2076-0817"]}, url={https://doi.org/10.3390/pathogens11060692}, DOI={10.3390/pathogens11060692}, abstractNote={Necrotic enteritis (NE) in poultry is an economically important disease caused by Clostridium perfringens type A bacteria. A global trend on restricting the use of antibiotics as feed supplements in food animal production has caused a spike in the NE incidences in chickens, particularly in broiler populations. Amongst several non-antibiotic strategies for NE control tried so far, probiotics seem to offer promising avenues. The current review focuses on studies that have evaluated probiotic effects on C. perfringens growth and NE development. Several probiotic species, including Lactobacillus, Enterococcus, Bacillus, and Bacteroides bacteria as well as some yeast species have been tested in chickens against C. perfringens and NE development. These findings have shown to improve bird performance, reduce C. perfringens colonization and NE-associated pathology. The underlying probiotic mechanisms of NE control suggest that probiotics can help maintain a healthy gut microbial balance by modifying its composition, improve mucosal integrity by upregulating expression of tight-junction proteins, and modulate immune responses by downregulating expression of inflammatory cytokines. Collectively, these studies indicate that probiotics can offer a promising platform for NE control and that more investigations are needed to study whether these experimental probiotics can effectively prevent NE in commercial poultry operational settings.}, number={6}, journal={PATHOGENS}, publisher={MDPI AG}, author={Kulkarni, Raveendra R. and Gaghan, Carissa and Gorrell, Kaitlin and Sharif, Shayan and Taha-Abdelaziz, Khaled}, year={2022}, month={Jun} }