About

Sheila Jacobi is an Associate Professor at The Ohio State University in the Department of Animal Sciences, located in the Animal Science Building. Her professional role involves research and teaching within the field of animal sciences, contributing to the academic and practical understanding of animal-related topics. Her contact information includes her office number at 122D Animal Science Building and her phone number at 614-247-7863.

Research topics

• Internal medicine
• Biology
• Animal science
• Biochemistry
• Medicine
• Endocrinology
• Food science
• Chemistry

Selected publications

• Impact of intramammary infections on mammary gland development in pregnant dairy heifers during late gestation

  Journal of Dairy Science · 2025-09-04 · 2 citations

  articleOpen access

  Intramammary infections are common in nonlactating dairy cattle and have been shown to disrupt mammary tissue architecture in nonpregnant heifers. However, their effect on mammary development during pregnancy remains unclear. This study assessed the effects of IMI on mammary gland development in pregnant dairy heifers during late gestation. The study used 21 pregnant Holstein heifers, divided across 3 gestational stages (∼5.75, 6.75, and 7.75 mo of gestation; corresponding to 180 ± 2, 208 ± 2, and 238 ± 2 d pregnant, respectively). Using a contralateral quarter-pair design, a single culture-negative quarter of each heifer was infused with saline (SAL), and the contralateral quarter was challenged with 5,000 cfu of Staphylococcus aureus (CHALL). Mammary secretion samples were collected at various time points until tissue harvest at 21 d postchallenge, when animals were 6.5, 7.5, and 8.5 mo pregnant. Mammary tissue samples from the center and edge parenchymal regions were collected and evaluated for immune cell infiltration and tissue morphometry. Secretions from CHALL quarters had greater SCC and a greater proportion of neutrophils compared with SAL quarters. Mammary tissues from CHALL quarters exhibited increased immune cell infiltration in both the luminal and intralobular stromal regions and lower secretion score compared with SAL, regardless of gestational stage. Additionally, tissues from animals at later gestational stages showed reduced adipose tissue area and larger lobular areas, regardless of quarter treatment. At 8.5 mo of pregnancy, luminal areas in the edge regions of CHALL quarters were nearly 50% smaller than in SAL quarters, suggesting an increased risk to restricting milk accumulation and secretion capacity in the mammary gland. Additionally, in 7.5-mo pregnant heifers, CHALL quarters showed decreased epithelial areas and increased intralobular stromal areas in the central region. Lobular, adipose, and extralobular stromal areas did not differ markedly between CHALL and SAL quarters. Overall, the results of this study indicate that IMI induces tissue damage in mammary glands of pregnant heifers, with a greater effect during late gestation, and that the IMI-induced changes in tissue architecture were not consistent across all tissue mammary gland regions or gestational ages.

  PublisherDOI

• PSV-21 <i>Pediococcus acidilactici</i> survives an in vitro simulated digestion

  Journal of Animal Science · 2024-05-01 · 3 citations

  articleOpen accessSenior author

  Abstract In the swine industry, probiotics are recognized for optimizing growth performance and production efficiency by modulating host physiology, and the response across studies is not consistent. One area of focus is probiotic mitigation of post-weaning diarrhea, and further mechanistic understanding of probiotic and host physiology could help with consistent performance outcomes. An essential attribute of a probiotic is the ability to survive the harsh environments of the gastrointestinal tract (GIT). The aim of this study was to determine if Pediococcus Acidilactici PECh3A (PA) that has been previously genome sequenced for determining gut physiology mechanisms can survive an in vitro simulated digestion. In the in vitro digestion PA concentrations that were investigated included 108, 109, and 1010 colony forming units (CFU)/mL. The in vitro digestion (n = 4/concentration) consisted of 5 phases with incubation times simulating the GIT; initial inoculation (0 h), gastric (2 h), upper intestinal (4 h), lower intestinal (9 h) and extended lower intestinal phase (9 h). For the initial inoculation concentrations of PA were added into 25 mL of sterile milk replacer representing dietary requirements of a suckling pig. In the gastric phase pepsin was added and pH was adjusted to 2.5. In the upper intestinal phase bile and pancreatin were added, along with a pH adjustment to 6.8. In the lower intestinal phase, the multi-enzyme complex consisting of carbohydrase enzymes was added and pH adjusted to 4.8. There was no addition during the extended lower intestinal phase. At each sample collection at the end of a phase 1 mL was collected from each flask. For each sample, 100 µL were serially diluted, plated on deMan, Rogosa, and Sharpe (MRS) plates, and incubated at 37°C for 24h. Survivability was determined by counting CFUs and comparing the concentration with the initial CFU/mL at 0 h and reported as percent survival (%S). Data for the in vitro digestion were analyzed according to a randomized complete block design (RCBD) in a split plot using the Repeated Measures Glimmix Procedure of SAS. Additional orthogonal contrasts were analyzed across PA concentrations. Data showed survival for 108,109, and 1010CFU/mL at all sample phases (108 - 44.24, 60.14, 58.36, 55.69%S; 109 - 40.56, 55.60, 49.35, 50.7%S; 1010 - 32.98, 52.55, 46.72, 43.71%S ± 2.98 respectively; phase P &amp;lt; 0.01 and concentration P &amp;lt; 0.01). There is evidence of a phase and concentration effect on survivability, but no interaction. A linear concentration response was observed across concentrations (54.61, 49.05, 43.99%S ± 1.23; P &amp;lt; 0.05) indicating that as concentration increases the survivability decreases. These findings indicate that PA PECh3A can survive a simulated GIT and potentially impact swine intestinal physiology.

  PublisherOA PDFDOI

• Discovery of steroidal alkaloid metabolites and their accumulation in pigs after short-term tomato consumption

  bioRxiv (Cold Spring Harbor Laboratory) · 2024-02-08 · 1 citations

  preprintOpen access

  ABSTRACT Scope Whole tomato consumption has been shown to be more effective than lycopene alone against chronic disease risks, suggesting other phytochemicals play a role in the health properties of tomato-rich diets. Recently, metabolites of tomato steroidal alkaloids, an understudied class of secondary plant compounds, have been found in plasma, tissues, and urine. However, a comprehensive, targeted analysis to determine which steroidal alkaloid metabolites are present after tomato consumption is lacking. This study profiles and quantifies tomato steroidal alkaloids in blood for the first time. Methods and results In a two-week parallel-arm study, piglets (n = 20) were fed diets containing 10% tomato powder or a macronutrient-matched control. Steroidal alkaloids were extracted from plasma and quantified using LC-MS. Tomatidine and alpha-tomatine were detected in plasma and confirmed with standards, while mass fragmentation spectra aided in identifying 31 additional metabolites representing 9 unique masses. Concentrations averaged to 107.7 nmol/L plasma, comprising of phase I (66%) and phase II (4.5%) metabolites. Conclusion These results describe the profile and concentration of steroidal alkaloid metabolites in pig plasma after short-term tomato consumption. Our methodology and findings allow for future investigations of tomato steroidal alkaloid bioactivity using physiologically appropriate levels.

  PublisherOA PDFDOI

• 180 Dietary milk fat globule membrane alters intestinal microbiota of neonatal piglet following lipopolysaccharide challenge and marker of neuroinflammation

  Journal of Animal Science · 2024-05-01

  articleOpen accessSenior author

  Abstract Early life stress exposure can increase morbidity and reduce animal wellbeing throughout life. Dysregulated gut function has been associated with neurological changes, and neurological changes affect gut homeostasis. Maternal milk is the gold-standard for yielding developmental benefits to offspring. Identification of milk components has led to an understanding of the bioactive nutrients important in neonatal development. Components of the milk fat globule membrane (MFGM) contribute immensely to neonatal gut health and neurodevelopment. However, mechanisms of actions are still being defined. The objective is to understand how dietary MFGM modulates the gut microbiota, blood-brain barrier tight junctions, and brain inflammatory markers following lipopolysaccharide (LPS) challenge. Piglets (n = 24, one-d-old) were assigned to soy (CON) or MFGM phospholipid supplemented diet (0.75% wt/wt) ± LPS (100 µg/kg body weight) in a 2 × 2 factorial design (n = 6 animals•diet-1•challenge-1.). Piglets were fed for 21 d and 6 animals/diet received saline or LPS injections 4 h before euthanasia. Colonic microbiota was characterized through 16s rRNA gene sequencing, while hypothalamus samples were collected to evaluate brain barrier function and inflammation-related genes using RT-qPCR. Microbiota data were processed using QIIME2 with DADA2 plugin and analyzed for alpha-diversity, beta-diversity, and differential abundance in R software. Gene transcription data were analyzed by a 2 × 2 experimental factorial design using the PROC MIXED procedure of SAS. Principal coordinates analysis indicated that MFGM-fed groups exhibited an observable separation from CON-fed groups in terms of microbial community structures (P &amp;lt; 0.05). Firmicutes_A, Bacteroidota, and Firmicutes_D were the predominant phyla across all treatments, with average proportions to be 52.21 %, 24.36 %, and 18.46 %, respectively. At genus level, MFGM + Saline group down-regulated Corynebacterium by 88.00 % (q &amp;lt; 0.05) and Unclassified Muribaculaceae by 73.33 % (0.050.05). However, there was an MFGM × LPS interaction (P &amp;lt; 0.05) observed for nuclear factor of kappa light polypeptide gene enhancer in B cells inhibitor alpha, in which MFGM attenuated the LPS-induced increase in mRNA relative abundance (3.62 and 2.39 ± 0.38). In conclusion, dietary MFGM altered neonatal piglet intestinal microbiota and an important signaling molecule of the neuroinflammatory response following LPS challenge.

  PublisherOA PDFDOI

• Discovery of steroidal alkaloid metabolites and their accumulation in pigs after short-term tomato consumption

  Food Chemistry · 2024-09-17 · 3 citations

  article
  PublisherDOI

• PSVI-13 Dietary Milk Fat Globule Membrane Improves Neonatal Piglet Intestinal Architecture and Enhances Mucosal Diamine Oxidase Activity Following Lipopolysaccharide Challenge

  Journal of Animal Science · 2023-11-06

  articleOpen accessSenior author

  Abstract Early life stressors alter the trajectory of gut development and impair nutrient utilization, barrier function, and animal performance throughout life. Gastrointestinal (GI) maladies increase morbidity and mortality in neonates, and dietary nutrients are essential in supporting GI function. Although maternal milk is the gold-standard for yielding developmental benefits to offspring, genetic selection in the modern sow has resulted in large litter size and milk yield potentially insufficient to achieve the high biological growth potential in sow-reared piglets. Research into milk quality has led to the identification of many bioactive nutrients important in neonatal development. Components of the milk fat globule membrane (MFGM) contribute immensely to neonatal nutrition and gut health. However, mechanisms of actions are still being defined. The objective is to define the effect of MFGM supplementation on neonatal piglet intestinal health. We hypothesize dietary MFGM will enhance piglet intestinal architecture and tight junction (TJ) protein abundance, attenuating systemic lipopolysaccharide (LPS)-induced intestinal barrier disruption. One-day-old piglets (n = 32) were assigned to soy (CON) or MFGM phospholipid supplemented diet (0.75% wt/wt) ± LPS (100 µg/kg body weight) challenge in a 2 × 2 factorial design (n = 8/diet/challenge). Piglets were fed for 21 d and 8 animals/diet received saline or LPS injections 4 h before euthanasia. Piglet weights and feed intake were recorded daily to calculate performance. Intestinal tissues were collected to assess villus height (VH) and crypt depth (CD) by hematoxylin and eosin staining. Two biomarkers of intestinal integrity, intestinal fatty acid-binding protein (I-FABP) and diamine oxidase (DAO), were measured in serum or tissue. Protein abundance of claudin-1 and occludin in ileal and colonic mucosa were detected by Western blot. Data were analyzed by 2 × 2 factorial arrangement of traetments using the PROC MIXED. Dietary MFGM had no adverse impact on growth performance or TJ proteins (P &amp;gt; 0.05). Dietary MFGM increased VH (CON: 348.8 and MFGM: 427.0 ± 26.79 µm) and decreased CD (CON: 166.3 and MFGM: 147.4 ± 8.42 µm) in ileum, thereby increasing the VH: CD ratio (CON: 2.2; MFGM: 3.1 ± 0.13; P &amp;lt; 0.05). Further, LPS treatment increased serum I-FABP by 4.4-fold and decreased jejunal mucosal DAO by 0.5-fold compared with saline treatment (P &amp;lt; 0.05). Additionally, there was a 93.1 % increase in colon DAO activity with MFGM diet compared with soy-fed pigs, regardless of LPS challenge (P &amp;lt; 0.05). Dietary MFGM improved neonatal piglet ileum architecture and increased colon DAO activity, potentially attenuating the intestinal barrier disruption following LPS challenge.

  PublisherOA PDFDOI

• Cellular proliferation and apoptosis in Staphylococcus aureus–infected heifer mammary glands experiencing rapid mammary gland growth

  Journal of Dairy Science · 2023-02-22 · 9 citations

  articleOpen access

  Intramammary infections in nonlactating mammary glands are common and can occur during periods of rapid mammary epithelial cell (MEC) accumulation, which may ultimately reduce total MEC numbers. Reduced MEC numbers, resulting from impaired MEC proliferation and increased cellular apoptosis, are expected to reduce future milk yields. The objective of this study was to measure the degree of cellular proliferation and apoptosis in the epithelial and stromal compartment of uninfected and Staphylococcus aureus-infected mammary glands hormonally induced to grow rapidly. Nonpregnant heifers (n = 8) between 11 and 14 mo of age were administered supraphysiological injections of estradiol and progesterone for 14 d. One mammary gland of each heifer was randomly selected and infused with Staph. aureus (CHALL) while another mammary gland was designated as an uninfected control on d 8 of injections. Mammary tissues were collected on the last day of hormonal injections from center and edge parenchymal regions and subject to proliferation assessment via Ki-67 staining and apoptotic assessment via terminal deoxynucleotidyl transferase dUTP nick-end labeling. Differences in cellular proliferation between CHALL and uninfected control quarters were not apparent, but proliferation of MEC was marginally greater in edge parenchyma than in center parenchyma. Coincidently, CHALL quarters experienced a greater percentage of apoptotic MEC and lower percentage of stromal cells undergoing apoptosis than uninfected control quarters. This study also provides the first insight into the mechanisms that allow the mammary fat pad to be replaced by expanding mammary epithelium as edge parenchyma contained a greater percentage of apoptotic stromal cells than center parenchyma. When taken together, these data suggest that Staph. aureus intramammary infection impairs mammary epithelial growth through reductions in MEC number and by preventing its expansion into the mammary fat pad. These factors during periods of rapid mammary growth are expected to impair first lactation milk yield.

  PublisherOA PDFDOI

• PSIII-2 <i>Pediococcus Acidilactici</i> Demonstrates Probiotic Properties and Inhibits the Growth of Enterotoxigenic <i>Escherichia Coli</i>

  Journal of Animal Science · 2023-11-06 · 1 citations

  articleOpen accessSenior author

  Abstract Lactic acid bacteria are recognized to possess probiotic properties including modulating host physiology. Probiotics are used as direct-fed microbials in the swine industry to optimize pig performance and production efficiency. In the nursery, probiotics have been shown to mitigate post-weaning diarrhea caused by enterotoxigenic Escherichia coli (ETEC). Studies show beneficial effects of supplementing probiotics and the data were inconsistent. Microbial genome sequencing could help better define the mechanisms of probiotic mode of action and dose required to improve probiotic efficacy. The aim of this study was to determine if Pediococcus acidilactici PECh3A (PA) that has been genome sequenced for determining gut physiology mechanisms expresses probiotic properties in-vitro. The growth curve of PA was conducted to determine colony forming units (CFU)/mL concentrations in 2-hour intervals until plateau at 15 hours. Based on the results of the growth curve dose response analysis were performed for acid and bile tolerance and antimicrobial activity against ETEC (3030-2: K88ac LT and STb). Doses investigated were 1010, 109, and 108 CFU/mL. For the acid and bile tolerance experiment PA was grown to concentration 1010 CFU/mL and was centrifuged and inoculated in De Mab, Rogosa, and Sharpe broth (MRS Broth) at pH 2, 4, or 6.5 (control) or MRS ± 0.3% oxgall (wt/vol), respectively, and incubated for 4 h. Following the 4 h incubation samples were serially diluted, plated, and incubated at 37°C for 24 h to determine percent survival. Antimicrobial inhibition of ETEC was assessed by the agar zone of inhibition (ZOI) methods. PA was grown to previously defined CFU/mL concentrations and 100 µL of the culture and filtered supernatant were plated into wells on nutrient agar plates spread with 107 ETEC CFU/mL. ZOI were measured in mm. Data were analyzed according to a factorial design using PROC MIXED procedures in SAS. Survival in acidic media relative to control media was observed in all doses (108,109, and 1010) at pH 4 and minimally at pH 2 (81.8, 90.6, and 89.5% or 33.8, 28.0, and 0% ±7.7, respectively; P &amp;lt; 0.01). PA survival in 0.3% oxgall increased with increasing dose (74.3, 83.3, and 91.7% ±0.67; P &amp;lt; 0.01). PA culture exhibited antimicrobial activity against ETEC at all doses tested, and the PA filtered supernatant exhibited antimicrobial activity from 109 CFU/mL (4.260 mm ± 0.9437, P &amp;lt; 0.01). Taken together the findings indicate that PA PECh3A exhibits functional probiotic properties to potentially improve swine intestinal physiology. Further in vitro and in vivo experiments will access Pediococcus acidilactici PECh3A function and interaction within the host environment.

  PublisherOA PDFDOI

• Dietary Prebiotic Oligosaccharides and Arachidonate Alter the Fecal Microbiota and Mucosal Lipid Composition of Suckling Pigs

  Journal of Nutrition · 2023-06-20 · 13 citations

  articleOpen accessSenior authorCorresponding
  PublisherOA PDFDOI

• Short term tomato consumption alters the pig gut microbiome towards a more favorable profile

  bioRxiv (Cold Spring Harbor Laboratory) · 2022-05-13

  preprintOpen access

  ABSTRACT Diets rich in fruits and vegetables have been shown to exert positive effects on the gut microbiome. However, little is known about the specific effect of individual fruits or vegetables on gut microbe profiles. This study aims to elucidate the effects of tomato consumption on the gut microbiome, as tomatoes account for 22% of vegetable consumption in Western diets, and their consumption has been associated with positive health outcomes. Using piglets as a physiologically relevant model of human metabolism, 20 animals were assigned either to a control or tomato powder supplemented diet (both macronutrient matched and isocaloric) for 14 days. The microbiome was sampled rectally at three time points: day 0 (baseline), day 7 (midpoint), and at day 14 (end of study). DNA was sequenced using shotgun metagenomics, and reads were annotated using MG-RAST. There were no differences in body weight or feed intake between our two treatment groups. There was a microbial shift which included a higher ratio of Bacteroidota to Bacillota (formerly known as Bacteroidetes and Firmicutes, respectively) and higher alpha-diversity in tomato-fed animals, indicating a shift to a more desirable phenotype. Analyses at both the phyla and genera levels showed global microbiome profile changes (PERMANOVA P ≤ 0.05) over time, but not with tomato consumption. These data suggest that short-term tomato consumption can beneficially influence the gut microbial profile, warranting further investigation in humans. IMPORTANCE The composition of the microorganisms in the gut is a contributor to overall health, prompting the development of strategies to alter the microbiome composition. Studies have investigated the role of the diet on the microbiome, as it is a major modifiable risk factor contributing to health; however, little is known about the causal effects of consumption of specific foods on the gut microbiota. A more complete understanding of how individual foods impact the microbiome will enable more evidence-based dietary recommendations for long-term health. Tomatoes are of interest as the most consumed non-starchy vegetable and a common source of nutrients and phytochemicals across the world. This study aimed to elucidate the effect of short-term tomato consumption on the microbiome, using piglets as a physiologically relevant model to humans. We found that tomato consumption can positively affect the gut microbial profile, which warrants further investigation in humans.

  PublisherOA PDFDOI

Frequent coauthors

• Jack Odle

  North Carolina State University

  40 shared

• Xi Lin

  30 shared

• Tina M. Herfel

  7 shared

• Rui Zheng

  First People's Hospital of Yunnan Province

  6 shared

• B.A. Corl

  Virginia Tech

  5 shared

• Kwan Seob Shim

  Jeonbuk National University

  5 shared

• Daniel Clark

  University of Pittsburgh

  5 shared

• Zeina E. Jouni

  Aix-Marseille Université

  5 shared

Awards & honors

• Fechheimer Lecture Series