About

Sarah Ho is the CVM Director of Student Engagement at the College of Veterinary Medicine at NC State University. Her role involves overseeing student engagement initiatives, fostering a supportive and collaborative campus community, and promoting student success and well-being. She is actively involved in creating opportunities for students to enrich their academic experience, including study abroad programs, research projects, and extracurricular activities. Her focus is on building a welcoming environment where students can develop professionally and personally, contributing to the college's mission of shaping the future of veterinary medicine.

Research topics

• Medicine
• Biology
• Microbiology
• Veterinary medicine
• Virology
• Surgery
• Pathology
• Internal medicine
• Ecology
• Toxicology
• Gastroenterology
• Nursing
• Zoology

Selected publications

• Comparison of Intrarenal and Intravenous Injections of Sodium Pentobarbital for Euthanasia in New Zealand White Rabbits (Oryctolagus cuniculus)

  UNC Libraries · 2026-04-22

  articleOpen access

  Peripheral venous access in rabbits can be difficult to obtain. When failure occurs, there is a dire need for alternative vascular access routes to be available. The AVMA categorizes intrarenal injection of pentobarbital as acceptable with conditions for euthanasia. Animals must be in an unconscious state, and only minimal studies using intrarenal administration have been reported. A total of 53 rabbits were used to conduct 3 separate analyses to assess and measure the efficacy, efficiency, and validity of the intrarenal route for euthanasia in New Zealand White rabbits by assessing the time to cardiopulmonary arrest (TCPA). Animals were sedated with 40 mg/kg ketamine and 50 μg/kg dexmedetomidine intramuscularly into the lumbar muscles, and timing started at the beginning of the injection and ended when cardiac and respiratory arrest were observed. Cardiac and respiratory arrest following intravenous injection of pentobarbital was significantly quicker (cardiac, 6 to 24 s, median 9 s; respiratory, 6 to 19 s, median 9 s; P < 0.001) than for the intrarenal route (cardiac, 40 to 900 s, median 411 s; respiratory, 23 to 900 s, median 120 s; P < 0.001), with no negative animal reactions observed during euthanasia injection performance. Four animals did not achieve TCPA within 15 min after administration. Although TCPA was longer with intrarenal compared with intravenous euthanasia ( P < 0.001), this study demonstrates that the intrarenal approach under anesthesia is a feasible alternative to the intravenous approach, as it can be reliably performed without observed animal distress or alterations in organ pathology. The overall information from this study can help guide both laboratory and practicing clinicians considering this technique. Still, factors such as variable times to cardiopulmonary arrest and technical skill should be considered.

  PublisherDOI

• Flumazenil has a dose-dependent effect on recovery from midazolam sedation in Rhode Island Red chickens (Gallus gallus domesticus)

  American Journal of Veterinary Research · 2026-04-07

  articleOpen access

  Objective: To evaluate the pharmacodynamics of 3 doses of IM flumazenil following 5 mg/kg midazolam, IM, in Rhode Island Red chickens. Methods: Using a randomized, crossover design, hens received IM midazolam followed 25 minutes later by 1 of 4 treatments IM: 0.02, 0.05, or 0.1 mg/kg flumazenil or an equal volume of 0.9% sodium chloride (control). Serial assessment of heart and respiratory rates, sedation scores, and times to recumbency and standing were recorded from midazolam administration until recovery. Chickens not recovered by 3 hours after midazolam received 0.05 mg/kg flumazenil, IM (rescue). Categorical variables were analyzed with the Cochran Q test, whereas noncategorical variables were evaluated with a mixed-effects γ regression model. The Pearson correlation and intraclass correlation coefficient measured correlation between observers. Results: All six Rhode Island Red hens became recumbent following midazolam administration. Heart and respiratory rates remained within clinically acceptable limits. Median (range) time to recovery following 0.02, 0.05, or 0.1 mg/kg flumazenil or control was 153.9 (55.2 to 180.0), 137.3 (35.5 to 181.0), 70.7 (29.6 to 182.0), and 173.0 (151.0 to 181.0) minutes, respectively. This was statistically significant between groups. Rescue flumazenil was administered in 3 of 6, 3 of 6, 1 of 6, and 5 of 6 birds in 0.02, 0.05, and 0.1 mg/kg flumazenil or control, respectively. Conclusions: In chickens sedated with 5 mg/kg midazolam, IM, 0.1 mg/kg flumazenil provided the fastest time to recovery compared to lower doses (0.02 and 0.05 mg/kg) or control. Clinical Relevance: This study supports the use of 0.1 mg/kg flumazenil, IM, to expedite recovery in midazolam-sedated chickens.

  PublisherDOI

• Rabbits with liver lobe torsion commonly exhibit gastric dilation, a rounded right hepatic silhouette, and peritoneal fluid on radiographs

  American Journal of Veterinary Research · 2026-01-26

  articleOpen access

  Objective: To describe and quantify selected radiographic findings of rabbits diagnosed with liver lobe torsion (LLT). Methods: The study included 50 rabbits with an antemortem diagnosis of LLT with radiographs made within 72 hours of diagnosis via ultrasound. Medical records from 2010 to 2020 from 4 institutions were reviewed. A board-certified radiologist reviewed the radiographs. Radiographic evaluation of gastric size was assessed on the right lateral view (caudal extent of the stomach relative to the lumbar vertebral column, gastric height and width, and vertebral stomach score), as well as gastric content patterns and radiographic signs of intestinal dilation and content, hepatic rounding, and loss of serosal detail. Loss of abdominal serosal detail was compared to the presence of peritoneal fluid on ultrasound. Results: 35 of 50 rabbits (70%) had a gastric height and gastric width sum height greater than or equal to the length from the L1 cranial endplate to the coxofemoral joint. The median vertebral stomach score was 8.8. The gastric content was mostly ingesta. A rounded margin along the right hepatic silhouette in the ventrodorsal view was identified in 30 of 50 rabbits (60%). Peritoneal fluid was correctly identified radiographically in 37 studies (74%), not appreciated but present in 7 (14%), correctly identified as not present in 4 (8%), and incorrectly identified in 2 (4%). Conclusions: Radiographic findings suggested that gastric dilation with ingesta, a rounded right hepatic silhouette, and peritoneal fluid, although not always present, are common in rabbits with LLT. Clinical Relevance: Identification of these findings should prompt further diagnostic imaging.

  PublisherDOI

• Intranasal alfaxalone in cockatiels (Nymphicus hollandicus) does not produce sedation compared to intramuscular alfaxalone with or without midazolam

  American Journal of Veterinary Research · 2025-04-03

  articleOpen access

  Objective: To compare the sedative effects of intranasal (IN) alfaxalone to IM alfaxalone with or without IM midazolam in cockatiels (Nymphicus hollandicus). Methods: A prospective, blinded, crossover study was performed on 8 healthy male cockatiels from February through April 2021. Birds randomly received 4 treatments with at least a 1-week washout period: alfaxalone at 15 mg/kg, IN (IN-A); alfaxalone at 15 mg/kg, IM, with (IM-AM) or without (IM-A) midazolam at 3 mg/kg, IM; and midazolam at 3 mg/kg, IM (IM-M). Time to recumbency and heart and respiratory rates were recorded. Ten minutes following administration, birds were restrained for sham 2-view radiographs and venipuncture. Following venipuncture, flumazenil at 0.1 mg/kg, IM, was administered (IM-AM and IM-M). Time to standing was recorded. Data were analyzed using a linear mixed model, a mixed effects γ-regression model, and Cochran Q, Friedman, and Wilcoxon signed-rank tests. Results: No sedative effects were observed in IN-A. Recumbency was achieved in 0/8, 5/8, 8/8, and 0/8 birds in IN-A, IM-A, IM-AM, and IM-M, respectively. Respiratory and heart rates remained within acceptable limits in all birds. Sham radiographs were acquired in 0/8, 1/8, 6/8, and 0/8 birds in IN-A, IM-A, IM-AM, and IM-M, respectively. Venipuncture was successful in all birds with median lactate concentrations of 4.9, 2.4, 1.0, and 1.8 mmol/L in IN-A, IM-A, IM-AM, and IM-M, respectively. Median (range) time to standing after handling in IM-A and IM-AM was 8.8 (0 to 15.0) and 14.5 (0.6 to 15.5) min, respectively. Conclusions: Intranasal alfaxalone at 15 mg/kg did not produce sedation. Clinical Relevance: Intramuscular alfaxalone at 15 mg/kg with midazolam at 3 mg/kg produced sedation in cockatiels.

  PublisherDOI

• Comparison of Intrarenal and Intravenous Injections of Sodium Pentobarbital for Euthanasia in New Zealand White Rabbits (Oryctolagus cuniculus)

  Journal of the American Association for Laboratory Animal Science · 2025-06-18

  articleSenior author

  Peripheral venous access in rabbits can be difficult to obtain. When failure occurs, there is a dire need for alternative vascular access routes to be available. The AVMA categorizes intrarenal injection of pentobarbital as acceptable with conditions for euthanasia. Animals must be in an unconscious state, and only minimal studies using intrarenal administration have been reported. A total of 53 rabbits were used to conduct 3 separate analyses to assess and measure the efficacy, efficiency, and validity of the intrarenal route for euthanasia in New Zealand White rabbits by assessing the time to cardiopulmonary arrest (TCPA). Animals were sedated with 40 mg/kg ketamine and 50 μg/kg dexmedetomidine intramuscularly into the lumbar muscles, and timing started at the beginning of the injection and ended when cardiac and respiratory arrest were observed. Cardiac and respiratory arrest following intravenous injection of pentobarbital was significantly quicker (cardiac, 6 to 24 s, median 9 s; respiratory, 6 to 19 s, median 9 s; P < 0.001) than for the intrarenal route (cardiac, 40 to 900 s, median 411 s; respiratory, 23 to 900 s, median 120 s; P < 0.001), with no negative animal reactions observed during euthanasia injection performance. Four animals did not achieve TCPA within 15 min after administration. Although TCPA was longer with intrarenal compared with intravenous euthanasia (P < 0.001), this study demonstrates that the intrarenal approach under anesthesia is a feasible alternative to the intravenous approach, as it can be reliably performed without observed animal distress or alterations in organ pathology. The overall information from this study can help guide both laboratory and practicing clinicians considering this technique. Still, factors such as variable times to cardiopulmonary arrest and technical skill should be considered.

  PublisherDOI

• PRELIMINARY HEMATOLOGY AND BIOCHEMISTRY REFERENCE INTERVALS IN JUVENILE BLACKTIP SHARKS (CARCHARHINUS LIMBATUS) IN THE GALÁPAGOS MARINE RESERVE

  Journal of Zoo and Wildlife Medicine · 2025-10-01 · 1 citations

  articleSenior authorCorresponding

  Species-specific hematology and biochemistry reference intervals (RIs) provide a crucial diagnostic resource for veterinarians, researchers, and wildlife managers working with elasmobranchs. This study aimed to establish hematologic and biochemical RIs from a population of free-ranging, juvenile blacktip sharks (Carcharhinus limbatus) in the Galápagos Marine Reserve in Ecuador. Heparinized blood samples were collected from the ventral coccygeal vein in 36 juvenile blacktip sharks captured via beach seine and physically restrained. Manual CBCs were performed, and heparinized plasma was submitted to a reference laboratory for biochemistry analysis. Per American Society for Veterinary Clinical Pathology guidelines, preliminary hematology and biochemistry RIs were determined minus white blood cell differentials due to artifact following blood smear storage and transport. Juvenile blacktip sharks in the Galápagos Marine Reserve had similar PCV (median: 28%, RI: 18.6–35%) but higher WBC concentrations (median: 29.9 × 103/µL, RI: 9.5–52.4 × 103/µL) than wild adult sandbar sharks (Carcharhinus plumbeus). Furthermore, juvenile blacktip sharks had lower plasma concentrations of aspartate aminotransferase (AST, median: 6 U/L, RI: 4–13 U/L), creatine kinase (CK, median: 16 U/L, RI: 6–90 U/L), and glucose (median: 58 mg/dL, RI: 39–78 mg/dL) than wild Atlantic sharpnose (Rhizoprionodon terraenovae) and bonnethead sharks (Sphyrna tiburo) may have been due to different capture methods. Hematology and biochemistry reference intervals will aid blacktip sharks under managed care and support future comparative and longitudinal research of blacktip shark populations within the Galápagos Marine Reserve.

  PublisherDOI

• Maropitant citrate exhibits rapid absorption, short half-life, and fast clearance in orange-winged Amazon parrots (Amazona amazonica) following subcutaneous and intravenous administration

  American Journal of Veterinary Research · 2025-04-04

  articleOpen accessSenior author

  Objective: To determine pharmacokinetic parameters after IV and SC administration of a single dose of maropitant. Methods: In this experimental study, adult orange-winged Amazon parrots were administered a single dose of maropitant (1 mg/kg) SC and IV with an 8-week washout period between experiments. Blood samples were collected at 0.5, 1.5, 2, 3, 6, 9, 12, and 24 hours after drug administration for the SC study. For the IV study, samples were taken at the same time points with additional collections at 5 minutes and 36 hours. Plasma maropitant was determined with LC-MS-MS, and pharmacokinetic parameters were calculated using a noncompartmental model. Results: A total of 8 orange-winged Amazon parrots (2 female and 6 male) were used in this study. Mean ± SD maximum concentration after SC administration was 130.9 ± 24.6 ng/mL and was reached at 0.5 ± 0 hours. Combined terminal half-life after SC administration was 6.67 hours. Bioavailability after SC administration was 85%. Plasma concentration at 24 hours was negligible and nearly identical between SC and IV administrations. Conclusions: A single dose of 1 mg/kg was well tolerated in all birds IV and SC. Maropitant rapidly attained plasma concentrations following SC administration and had a relatively high bioavailability and short half-life. Clinical Relevance: The results of this study suggest that the currently used doses and dosing intervals for maropitant in psittacine birds do not maintain above-target plasma concentrations considered therapeutic in dogs and may be insufficient to achieve systemic effects comparable to those observed in other species.

  PublisherOA PDFDOI

• Mydriasis in eastern box turtles (<i>Terrapene carolina carolina</i>) following topical administration of proparacaine, 10% phenylephrine, and rocuronium bromide

  Veterinary Ophthalmology · 2024-05-17

  articleOpen accessCorresponding

  OBJECTIVE: To determine the mydriatic effect of topical 10% phenylephrine with 10 mg/mL rocuronium bromide and compare this protocol with and without pretreatment with proparacaine. ANIMALS STUDIED: Ten client-owned pet adult eastern box turtles (Terrapene carolina carolina). PROCEDURES: All turtles were sedated with 8 mg/kg alfaxalone intramuscularly. One group of four turtles received four 20 μL drops of 10% phenylephrine and four 20 μL drops of rocuronium bromide in the right eye. Another group of four turtles received one standard drop of proparacaine followed by four 20 μL drops of 10% phenylephrine and four 20 μL drops of rocuronium bromide in the right eye. Two control group turtles received four 20 μL drops of saline in the right eye. The left eye was untreated in all turtles. Drops of the same type were separated by 2 min while drops of different types were separated by 5 min. Pupil size was recorded at 0, 15, 30, 60, 90, 120, 180, 240, and 360 min after administration of the final drop. RESULTS: Treatment with 10% phenylephrine and rocuronium bromide resulted in pupil diameter changes from baseline that were statistically significant from zero at 60, 90, and 120 min in the non-proparacaine group and 90 min in the proparacaine group. The time to peak effect was 90 min in the proparacaine group and 75 min in the non-proparacaine group. Saline-treated pupils in the control group decreased in diameter over the study period. Overall, the treated eyes of the proparacaine group and non-proparacaine group were not different from each other, but both dilated more than the control group. CONCLUSIONS: Rocuronium bromide and 10% phenylephrine can produce effective and safe mydriasis in eastern box turtles, but there was wide interindividual variation in effectiveness. Proparacaine did not improve the mydriatic effect.

  PublisherOA PDFDOI

• Medical Management of Reproduction in Birds

  Veterinary Clinics of North America Exotic Animal Practice · 2024-10-15 · 2 citations

  reviewSenior author
  PublisherDOI

• Osteosarcoma of the wing in a sulfur‐crested cockatoo

  Veterinary Clinical Pathology · 2024-01-02 · 2 citations

  articleOpen access

  A 26-year-old female sulfur-crested cockatoo (Cacatua galerita) was evaluated for vocalizing through the night and extending her right wing. Physical examination revealed a large, firm mass extending from the humerus to the distal aspect of the elbow. Computed tomography confirmed a large aggressive mass of the right distal humerus with a large soft tissue component, severe osteolysis, and adjacent periosteal proliferation. Fine-needle aspirates of the mass were most compatible with sarcoma, and osteosarcoma was prioritized. An unstained slide was treated with nitroblue tetrazolium chloride/5-bromo-4-chloro-3-indolyl phosphate toluidine salt-phosphatase (NBT/BCIP) substrate for ALP detection and was strongly positive, confirming a diagnosis of osteosarcoma. A month later, the patient underwent wing amputation and arrested during recovery from anesthesia. Post-mortem examination and histopathology were consistent with osteosarcoma. This case report highlights a rare occurrence of osteosarcoma in a cockatoo as well as its cytologic and histologic features. Additionally, this report provides support for NBT/BCIP application in ALP-expressing tumors, a cytochemical stain that has been minimally investigated in avian species.

  PublisherOA PDFDOI

Frequent coauthors

• Joanne Paul‐Murphy

  Zoological Society of San Diego

  22 shared

• Michelle G. Hawkins

  19 shared

• David Sánchez-Migallón Guzman

  University of California, Davis

  18 shared

• Philip H. Kass

  University of California, Davis

  18 shared

• Kellie A. Fecteau

  University of Tennessee at Knoxville

  16 shared

• Aslı Mete

  University of California, Davis

  16 shared

• Andrea Thomson

  North Carolina State University

  14 shared

• David Sánchez-Migallón Guzman

  University of California, Davis

  12 shared