Mark A. Mitchell’s research while affiliated with Louisiana State University and other places

Commercial cricket production has been plagued by viral disease outbreaks that have decimated their potential outputs and profit margins. To date, no epidemiological studies have been performed to estimate the prevalence of major viruses affecting crickets raised in commercial settings. A cross-sectional study was performed to estimate the prevalence of three important viruses (Acheta domesticus densovirus [AdDV], Acheta domesticus volvovirus [AdVVV], and invertebrate iridovirus 6 [CrIV]). Samples were collected across age groups (2-, 4-, and 6-week-olds) and seasons (January, May, August, and October) to determine the effect that these variables had on the prevalence rates. Quantitative real-time PCR was performed and revealed the following high overall prevalence rates: 46.7, 100, and 100% for AdDV, AdVVV, and CrIV, respectively. Viral loads varied from 101–5 for AdDV, 102–7 for AdVVV, and 102–9 for CrIV. AdDV prevalence rates were statistically significant across age and season (age: χ² = 8.3, p = 0.015; season: χ² = 59.7, p < 0.001), with crickets more likely to be infected as they aged and during the colder winter months. CrIV followed similar trends when looking at changes in viral loads between ages and seasons. AdVVV experienced a spike in viral loads across all ages during the month of August. Understanding the epidemiology of these viruses is instrumental in determining best management practices for commercially raised crickets.

Viscoelastic testing evaluates the formation and lysis of a clot over time, allowing more complete assessment of patient hemostasis in real time, whereas traditional tests, such as prothrombin time and partial thromboplastin time, only measure coagulation factor function. Patient-side viscoelastic coagulation monitors are easy to use, portable, and provide faster turnaround time than commercial laboratories. Viscoelastic testing requires only 0.2 mL of blood and is useful in diagnosing and treating hemostatic disorders. Currently, there is no standardized coagulation testing method across bird species. In this cross-sectional study, a viscoelastic coagulation device, the Entegrion Viscoelastic Coagulation Monitor-Vet (VCM-Vet), was evaluated. Blood samples were obtained from 26 Hispaniolan Amazon parrots (HAPs) (Amazona ventralis) under manual restraint. Results were recorded on the device as graphical output with quantitative viscoelastic measurements. Results were reported using standard rotational thromboelastometry terminology, including clotting time, clot formation time, alpha angle, maximum clot firmness, clot firmness amplitude at 10 and 20 minutes after clot formation, and clot lysis at 30 and 45 minutes. The median clotting time was 463 seconds (reference interval: 56-1635 seconds), the mean clot formation time was 704.7 seconds (reference interval: 172-1697 seconds), the mean alpha angle was 27.3 (reference interval: 7-60), and the mean maximum clot firmness was 15.4 (reference interval: 7-25). Statistical analysis found that all parameters were normally distributed aside from clotting time in seconds. There was no appreciable breakdown of the clot during the 60-minute device runtime, and there was no significant difference in any parameter based on sex. The VCM-Vet produced clotting times for this population of HAPs and enabled the creation of reference intervals. Based on our findings, the VCM-Vet can be used to assess clot potential in HAPs and possibly other avian species.

Over the last two decades, the insects-as-food-and-feed industry has rapidly emerged. Its growth is largely because insects require substantially less resources (water, food, and energy) to produce than traditional sources of animal protein, making it a sustainable alternative food option. As this industry continues to grow, veterinarians will likely be called upon to assist in identifying food safety concerns, assessing animal health, implementing biosecurity measures, and formulating/prescribing treatment protocols comparable to what we have seen with the honeybee industry and the institution of veterinary feed directives (VFDs). Similar to other agricultural markets, high animal densities and management practices put insects at high risk for infectious diseases. Veterinarians interested in working with these species will need to become knowledgeable regarding the diseases afflicting the feeder insect industry and how best to diagnose and treat pathogens of concern. Using the edible cricket industry as an example, this review will highlight health and production issues while drawing similarities to other traditional livestock operations. If the insects-as-feed-and-food industry is going to be viable, veterinary involvement will be essential to ensure that insects can be used as a safe source of food for all.

Anticoagulant choice can have significant effect on complete blood counts of reptiles and has not been reported in bearded dragons (Pogona vitticeps). Whole blood was collected from 14 captive individuals and aliquoted into separate blood tubes containing dipotassium ethylenediaminetetraacetic acid (EDTA) and lithium heparin. Samples were shipped and processed within 24 h. A CBC, including a WBC count using a commercial phloxine method, was performed on blood from both tubes. A WBC estimate, WBC differential, and morphologic review were performed on blood smears made from the anticoagulated blood, as well as on a direct blood smear made from anticoagulant-free blood. Some CBC values were significantly different between the EDTA and lithium heparin samples. Hematologic data generated from direct blood smears were more similar to data from EDTA samples than to data from lithium heparin samples. Additionally, multiple lithium heparin samples had poor phloxine stain uptake and leukocyte clumping, so that many WBC parameters were altered or unreportable. These results support EDTA as an appropriate anticoagulant for bearded dragon hematologic evaluation and suggest it may be superior to heparin for some individuals in generating a WBC count using a commercial phloxine method.

Anthropogenic activities have negatively affected many birds, including owls. The Wildlife Hospital of Louisiana (WHL) has seen a 3.2-fold increase in barred owl (Strix varia) cases over the past eight years (2023, 134; 2015, 42). Because most of these animals present with traumatic injuries, analgesics should be considered in their treatment plan. To date, no study has measured the pharmacokinetics of an analgesic in barred owls. The goals of this study were to determine the harmonic means, times to maximum concentration, and elimination half-lives for single 1 mg/kg and 2 mg/kg intramuscular doses of meloxicam. Twelve barred owls (1 mg/kg, n = 6; 2 mg/kg, n = 6) admitted to the WHL and determined to be clinically normal based on examination and blood work were recruited for this study. Meloxicam was administered intramuscularly, and blood samples were collected intermittently over 12 h to measure plasma concentrations using high-performance liquid chromatography. Both doses had rapid elimination half-lives (1 mg/kg, 0.99 ± 0.1 h; 2 mg/kg, 1.07 ± 0.43 h) and were below the limits of quantification (0.1 µg/mL) by 6–12 h. Based on these results, 1 and 2 mg/kg doses of meloxicam were found to produce plasma concentrations below therapeutic concentrations for less than four hours, making current twice-daily recommended dosing intervals unlikely to provide desired analgesia.

Simple Summary Common blue-tongued skinks (Tiliqua scincoides) are popular pets due to their docile temper. Because of their popularity, they are routinely presented to veterinarians for examinations or procedures; however, to date, there has been limited research evaluating sedation protocols for this species. This study aimed to test different sedation combinations in these skinks: alfaxalone alone, alfaxalone with midazolam, dexmedetomidine with midazolam, and a combination of alfaxalone, dexmedetomidine, and midazolam. All four combinations provided safe sedation, but there were different physiologic responses noted. According to our trials, the combinations of all three drugs or alfaxalone with midazolam are recommended for minor procedures. Abstract Common blue-tongued skinks (Tiliqua scincoides) are popular pet reptiles; however, there has been limited research to investigate sedatives for this species. The purpose of this study was to measure the physiologic effects of four combinations of alfaxalone, dexmedetomidine, and midazolam for minor procedures such as intubation and blood collection. Eleven common blue-tongued skinks (Tiliqua scincoides) were used for this prospective, randomized cross-over study. The subcutaneous combinations were used as follows: 20 mg/kg alfaxalone (A); 10 mg/kg alfaxalone and 1 mg/kg midazolam (AM); 0.1 mg/kg dexmedetomidine and 1 mg/kg midazolam (DM); and 5 mg/kg alfaxalone, 0.05 mg/kg dexmedetomidine, and 0.5 mg/kg midazolam (ADM). Heart rate, respiratory rate, palpebral reflex, righting reflex, escape reflex, toe pinch withdrawal reflex, tongue flicking, and the possibility of intubation were recorded at baseline and every 5 min for 60 min. Venous blood gases were measured at baseline, full sedation, and recovery. Heart and respiratory rates decreased significantly in all groups, but the reductions were most prominent in DM and ADM. Analgesic effects, as measured by the toe pinch withdrawal reflex, were only observed in DM and ADM. Intubation was possible in all four protocols; however, it was not possible in two DM skinks. Based on these trials, ADM and AM are recommended for minor procedures in blue-tongue skinks.

Dubia roaches (Blaptica dubia) are native to Central and South America, and this species is commonly offered to captive reptiles; however, our understanding of their nutritional value is limited. Moreover, they have a natural inverse calcium to phosphorous (Ca:P) ratio. Reptiles fed non-gut loaded insects are more susceptible to developing nutritional secondary hyperparathyroidism. The purpose of this study was to measure the nutritional content of these insects and determine whether a high-calcium (8% dry matter) commercial gut loading diet could be used to produce a positive Ca:P ratio in these insects. Roaches (0.2 g, 16 mm) were fasted for 24 hours and then randomly divided into a control group (n = 6, baseline) and three experimental groups (12 hours, 24 hours, 48 hours; n = 6 each). Each cohort (n) represented approximately 75- 80 roaches (15-18g). Roaches in the experimental groups were gut loaded on 50 g of the Fluker’s High-Calcium Dubia Roach Diet (Fluker Farms, Port Allen, LA, USA) for 12, 24, and 48 hours. All groups were humanely euthanized by isoflurane overdose and freezing at -80°C (-112°F). Samples were sent on ice packs to Dairy One (Ithaca, NY, USA) for nutritional analysis. At baseline, all control cohorts had a severe inverse Ca:P ratio (mean: 0.15±0.007, min-max: 0.14- 0.16); however, the Ca:P ratios were found to significantly increase at all three time points compared to baseline (P < 0.0001; all means > 1.4). These results confirm that dubia roaches fed a high-calcium diet can be used to provide an appropriate Ca:P ratio for captive reptiles.

Lactate is an important biochemistry analyte used in human and veterinary medicine to assess tissue perfusion and can be used as a prognostic indicator for certain disease conditions. Whereas lactate is commonly measured using "patient-side" handheld meters, these meters have not been validated for companion avian species. The purpose of this study was to measure the level of agreement between 2 commercially available point-of-care lactate meters and a laboratory benchtop blood analyzer in Hispaniolan Amazon parrots (Amazona ventralis). Blood samples were collected from 20 adult parrots at Louisiana State University by drawing 1.5 mL of blood from the right jugular vein. One drop of whole blood was used for the Lactate Plus analyzer and the remainder of the sample transferred into a lithium heparin microtainer. From the blood in the microtainer, 0.2 mL whole blood was analyzed using the epoc Blood Analysis System, and the remaining sample was centrifuged to obtain plasma that was immediately frozen at -80°C (-112°F) and submitted to the Texas A&M University Clinical Pathology Laboratory for analysis on the VITROS 4500 benchtop analyzer. Bland-Altman agreement plots and Passing-Bablok regression were used to measure the level of agreement between the methods. There was poor agreement between all 3 methods with mean percentage differences in lactate concentrations ≥22% (epoc and Lactate Plus: 33.6% [95% CI: 27-40]; epoc and VITROS 4500: 55% [95% CI:52-58]; VITROS 4500 and Lactate Plus: 22% [95% CI:16-28]). Based on these results, the point-of-care meters tested in this study are not interchangeable, and separate reference intervals were calculated for each method. Blood lactate concentrations may have more utility in tracing lactate trends over time in an individual rather than being able to utilize this information at 1 time point for disease diagnosis and prognosis.

Simple Summary Turtles and tortoises are routinely presented to veterinarians for medical and surgical treatment. In many of these cases, sedation is required to properly examine the animal and perform necessary diagnostic tests. Unfortunately, there is a dearth of evidence-based research available to guide veterinarians working with these animals. In addition, the available publications show that there are differences between species. Therefore, with nearly 350 species of chelonians in the world, it is important for us to evaluate protocols on a species-by-species basis. In this study, six eastern mud turtles (Kinosternon subrubrum) were given 10 mg/kg alfaxalone via intramuscular (IM) and intravenous (IV) routes using a cross-over study design that allowed us to compare the results between and within turtles. As expected, the IV route led to a faster induction and recovery. This study demonstrated that alfaxalone 10 mg/kg IV or IM can be used to provide safe and effective sedation in eastern mud turtles. Abstract Current sedation protocols for chelonians can pose a challenge to clinicians because of prolonged induction and recovery times, difficulties in gaining venous access, and natural species variation. This study evaluated the sedative and physiologic effects of intramuscular (IM) and intravenous (IV) alfaxalone in six wild-caught adult eastern mud turtles (Kinosternon subrubrum). The turtles received alfaxalone 10 mg/kg IM and IV in a randomized cross-over design. A 10-day washout period occurred between trials. Baseline parameters (heart rate, respiratory rate, temperature, and reflexes) were assessed prior to injection and every 5 min post-injection until recovery. Three venous blood gas samples were also collected and analyzed over the course of each trial (baseline, induction, and recovery). Intravenous alfaxalone resulted in a significantly faster induction (p = 0.016; median: 1.5 min, 25–75%: 1–7.5, minimum–maximum: 1–21) and a shorter total sedation time (p = 0.041; median: 52 min, 25–75%: 34.5–62.5, minimum–maximum: 33–87) when compared with IM alfaxalone (induction, median: 20 min, 25–75%: 15–22.5, minimum–maximum: 15–25; total, median: 70 min, 25–75%: 65–82.5, minimum–maximum: 65–90). Blood gas and physiologic parameters were not significantly different between groups; however, the pH (p = 0.009) and glucose (p = 0.0001) significantly increased, and partial pressure of carbon dioxide (p = 0.024) significantly decreased over time. This study demonstrated that alfaxalone 10 mg/kg IV or IM can be used to provide safe and effective sedation in eastern mud turtles.