Sandra D. Taylor

Clinical and clinicopathological factors associated with survival in 44 horses with equine neorickettsiosis (Potomac horse Fever).

BACKGROUND The epidemiology of equine neorickettsiosis (EN) has been extensively studied but limited clinical and clinicopathological data are available concerning naturally infected horses. HYPOTHESIS Factors predictive of survival will be identified in horses diagnosed with EN. ANIMALS Convenience sample of 44 horses with EN admitted to 2 referral institutions. METHODS A retrospective study was performed. A diagnosis of EN was based on the presence of positive blood or fecal PCR. RESULTS The most common clinical signs included diarrhea (66%), fever (50%), anorexia (45%), depression (39%), colic (39%), and lameness (18%). The median duration of hospitalization was 6 days and 73% of horses survived to discharge. Laminitis was present in 36% of horses, 88% of which were affected in all 4 feet. Serum creatinine and urea nitrogen concentrations, as well as RBC count, blood hemoglobin concentration, hematocrit, band neutrophils, serum AST activity, serum CK activity, and anion gap, were significantly (P < .05) higher in nonsurvivors. Serum chloride and sodium, concentrations as well as duration of hospitalization were significantly lower in nonsurvivors. The results of forward stepwise logistic regression indicated that blood hemoglobin concentration on admission and antimicrobial treatment with oxytetracycline were independent factors associated with survival. CONCLUSIONS AND CLINICAL IMPORTANCE Severity of colitis as reflected by electrolyte loss, hemoconcentration, and prerenal azotemia were predictors of survival in horses diagnosed with EN. Treatment with oxytetracycline was associated with increased survival.

Plasma C‐Reactive Protein and Haptoglobin Concentrations in Critically Ill Neonatal Foals

Background Accurate diagnostic markers for sepsis in neonatal foals are needed. Plasma C‐reactive protein concentration (p[CRP]) and haptoglobin concentration (p[Hp]) are well‐established biomarkers of infection in humans, but studies are lacking in foals. Hypotheses p[CRP]) and p[Hp] are increased in septic foals compared to sick nonseptic and healthy control foals, and are predictive of survival. Animals Eighty critically ill foals (40 septic, 40 sick nonseptic) and 39 healthy control foals <1 week of age. Methods Multicenter, prospective observational clinical study. Venous blood was collected at admission from septic and sick nonseptic foals and from clinically healthy foals at 24 h of age. A diagnosis of sepsis was made based on positive blood culture or a sepsis score >11, and p[CRP] and p[Hp] were measured by using ELISA tests. Data were analyzed by using the Mann‐Whitney U‐test and forward stepwise multivariable linear regression. P < .05 was considered significant. Results Plasma [CRP] was positively associated with age, serum globulin, adrenomedullin, and bilirubin concentrations, aspartate aminotransferase activity, glutamyl‐transferase activity, band neutrophil count, and rectal temperature, and was increased in foals with toxic neutrophils, enterocolitis, colic, rib fractures and septic arthritis. Surprisingly, p[Hp] was lower in septic foals than in sick nonseptic foals. Neither p[CRP] or p[Hp] was predictive of survival in critically ill foals. Conclusions and Clinical Importance Plasma [CRP] increases with inflammation in neonatal foals but is not indicative of sepsis. Single time point, admission sampling of p[CRP] and p[Hp] do not appear to be useful biomarkers for sepsis in foals.

Plasma Adrenomedullin Concentrations in Critically Ill Neonatal Foals

Background Bacterial sepsis remains a leading cause of morbidity and mortality in neonatal foals, but accurate diagnostic and prognostic markers are lacking. Adrenomedullin (AM) is a polypeptide with diverse biologic effects on the cardiovascular system that increases in septic humans and laboratory animals. Hypotheses Plasma AM concentration (p[AM]) is increased in septic neonatal foals compared to sick nonseptic and healthy control foals, and p[AM] is predictive of survival in septic neonatal foals. Animals Ninety critically ill (42 septic, 48 sick nonseptic) and 61 healthy foals <1 week of age. Methods A prospective observational clinical study was performed. Venous blood was collected from critically ill foals at admission and from healthy foals at 24 hours of age. Critically ill foals were categorized as septic or sick nonseptic based on blood culture results and sepsis score. Plasma [AM] was measured by using a commercially available ELISA for horses. Data were analyzed by using the Mann‐Whitney U‐test and P < .05 was considered significant. Results Plasma [AM] was not significantly different between septic and sick nonseptic foals (P = .71), but critically ill foals had significantly increased p[AM] compared to healthy controls (P < .0001). In critically ill foals, p[AM] was not predictive of survival (P = .051). A p[AM] cutoff concentration of 0.041 ng/mL provided a test sensitivity of 91% and specificity of 54% to predict illness. Conclusions and Clinical Relevance Plasma [AM] shows promise as a marker of health in neonatal foals, but p[AM] increases nonspecifically during perinatal illnesses and is not necessarily associated with sepsis.

Arsenic Toxicosis in Cattle: Meta-Analysis of 156 Cases

BACKGROUND Arsenic toxicosis is uncommon in cattle and successful treatment is rarely reported. OBJECTIVES This analysis reviews all cases of acute arsenic toxicosis in cattle reported in the literature and describes cases from Purdue University that had a favorable outcome. Clinical presentation of the disease, treatments, and variables associated with survival are described. ANIMALS One hundred and fifty-six cattle with arsenic toxicosis from 16 outbreaks. METHODS Meta-analysis. RESULTS The most common clinical signs were sudden death (68%), diarrhea (33%), ataxia (29%), dehydration (22%), and respiratory distress (4%). The most common clinicopathologic abnormalities included azotemia (100%), hematuria (100%), increased liver enzyme activity (86%), and increased hematocrit (60%). One percent of cattle survived and the survival time for nonsurvivors ranged from 20 hours to 21 days. None of the clinical signs or clinicopathologic findings was associated with survival. Treatment was attempted in 24% of cases and was not associated with survival (P = .055), but administration of an antidote and administration of fluids were associated with better outcome (P = .036 and P = .009, respectively). In the animals presented to Purdue University, treatment with IV fluids and sodium thiosulfate resulted in decreased blood arsenic concentrations in all animals (P = .009) and a survival rate of 50%. CONCLUSIONS AND CLINICAL IMPORTANCE Although acute arsenic toxicosis has a poor prognosis, survival is possible if aggressive fluid therapy and antidotes are administered.

Factors Associated with Survival in 97 Horses with Septic Pleuropneumonia

Background Septic pleuropneumonia is a common cause of morbidity and mortality in horses, but there is limited data available regarding factors associated with survival. Hypothesis/Objectives To identify factors predictive of survival in horses with septic pleuropneumonia. Animals A total of 97 horses with septic pleuropneumonia at 2 referral institutions. Methods A retrospective study was performed. A diagnosis of septic pleuropneumonia was based on the presence of sepsis, pleural effusion, and positive bacterial culture from tracheal aspiration (TA) or pleural fluid (PF). Results Thirty‐one percent of horses had a recent history of travel. Clinical signs included lethargy (78%), tachycardia (75%), tachypnea (60%), fever (43%), prolonged capillary refill time (22%), and ventral edema (14%). The most common clinicopathologic abnormality was hyperfibrinogenemia (79%). Increased serum creatinine concentration at presentation was negatively associated with survival (OR, 5.13; CI, 1.88–14.01; P = .001) and return to work (OR, 6.46; CI, 1.10–37.92; P = .034). Eighty‐four TA and 67 PF samples were submitted for culture, 98 and 84% of which were positive, respectively. The most common isolate was Streptococcus equi subsp zooepidemicus. Tracheal aspirates were more sensitive than PF for bacterial growth, but some organisms isolated from PF were not isolated from TA. Thoracotomy was positively associated with survival (OR, 0.13; CI, 0.01–0.83; P = .028). Conclusions and Clinical Importance Increased serum creatinine concentration is a negative prognostic indicator and is likely a reflection of dehydration. Submission of TA and PF is recommended. Thoracotomy should be considered as a treatment for pleuropneumonia.

Clinical findings and survival in 56 sick neonatal New World camelids.

Background Information pertaining to clinical presentation and outcome of neonatal New World camelids (NWC) is limited when compared to calves and foals. Hypothesis Values of variables at admission and subsequent treatment would predict survival in sick neonatal NWC. Animals Fifty‐six client‐owned sick neonatal NWC presented over a 10‐year period to the Purdue University Veterinary Teaching Hospital. Methods A retrospective study was performed. Inclusion criteria were NWC less than 30 days of age with complete medical records that presented between 2000 and 2010. Results The median age at presentation was 1 day (range 1–20). The most common diagnoses were systemic inflammatory response syndrome (50%), congenital defects (41%), ophthalmic lesions (21%), sepsis (16%), and gastrointestinal diseases (16%). Sixty‐six percent of NWC survived to discharge. Clinicopathologic findings on admission were variable and not specific for disorders. Factors associated with survival were absence of choanal atresia (P = .001, OR: 55.9 [2.5–1,232]), administration of llama plasma (P = .013, OR: 4.9 [1.4–17.7]), and antimicrobial treatment with trimethoprim‐sulfamethoxazole (TMS) (P = .016, OR: 6.5 [1.3–32.2]). Conclusions and Clinical Importance The use of antibiotics, particularly TMS, and llama plasma are recommended in sick neonatal NWC. Results from this study could contribute toward defining a NWC‐specific sepsis scoring system.

Effect of valacyclovir on EHV-5 viral kinetics in horses with equine multinodular pulmonary fibrosis

Background Equine herpesvirus‐5 is commonly isolated from the lungs of horses with EMPF, suggesting an etiological link. Valacyclovir is used empirically to treat EMPF; however, no data is available concerning its impact on EHV‐5 viral kinetics. Objectives To determine the effect of oral administration of valacyclovir on EHV‐5 viral load measured by qPCR in blood, nasal secretions (NS) and BALF in horses with EMPF. Animals Six horses diagnosed with EMPF. Methods A prospective clinical trial was performed. Horses received 10 days of PO administered valacyclovir (loading dose 30 mg/kg, maintenance dose 20 mg/kg). Blood, NS, and BALF were collected for EHV‐5 viral kinetics analyses during treatment. Blood and NS were collected every other day. BALF was collected on day 0 and day 10. Results There was no statistical difference in median EHV‐5 viral load between day 0 and day 10 for all samples tested. In blood median EHV‐5 viral load was 7676 (range 575‐39 781) on day 0 and 6822 (range 1136‐18 635) glycoprotein B (gB) gene copies per million cells on day 10. For NS median EHV‐5 viral load was 2.944 × 106 (range 184 691‐3.394 × 109) on day 0 and 8.803 × 106 (range 251 186‐9.868 × 108) gB gene copies per million cells on day 10. For BALF median EHV‐5 viral load was 59,842 (range 61‐315 655) on day 0 and 185 083 (range 3562‐542 417) gB gene copies per million cells on day 10. Conclusions and Clinical Importance Valacyclovir might not be an effective short‐term antiviral treatment but efficacy in treatment of EMPF is unknown.

Evaluation of three intravenous injectable anaesthesia protocols in healthy adult male alpacas

Few studies have investigated the effects of intravenous injectable anaesthesia in alpacas. The objective of this study was to evaluate three intravenous injectable anaesthesia protocols in healthy adult alpacas exposed to noxious stimulation. A prospective randomised crossover study was done using six healthy adult male alpacas. Cardiopulmonary variables including heart rate, respiratory rate, mean arterial pressure, end-tidal pCO2 and haemoglobin oxygen saturation were collected immediately after and every two minutes following induction of each of three anaesthesia protocols in six male castrated alpacas. A hoof tester was used to apply consistent pressure every two minutes after induction and the response was recorded. Time from induction to muscle contraction and leg withdrawal were recorded, as well as time from induction to extubation, sternal recumbency and standing. There was no significant difference in duration of anaesthesia or cardiopulmonary variables among the three anaesthesia protocols. Total duration of anaesthesia was approximately 20 minutes for each protocol. Hypoxaemia and mild hypercarbia were common among all protocols. Induction and recovery scores were excellent.

Neonatal Encephalopathy in Calves Presented to a University Hospital

Background While studies have examined bovine dystocia in relation to calf survival, little has been published regarding perinatal morbidity and treatment of newborn calves beyond failure of transfer of passive immunity (FTPI). Neonatal encephalopathy (NE) is a clinical syndrome commonly diagnosed in infants and foals but is poorly described in calves. Hypothesis/Objectives To identify risk factors for development of NE in calves and factors predictive of survival. Animals Neonatal calves presented to a University hospital over a 10‐year period. Methods Retrospective cohort study (2005–2015). Medical records of all neonatal calves presented to the hospital were examined, and cases of NE were identified. Data pertaining to demographics, dam parity, labor, treatment, and outcome were collected and analyzed with univariate and multivariate statistics. Results Of 200 calves in the final analysis, 58 (29%; 95% CI: 22.8–35.8%) were classified as NE and 142 calves as non‐NE. In univariate analysis, factors significantly associated with diagnosis of NE included male sex, presence of dystocia, abnormal position in the birth canal, and prolonged labor. In the multivariate model, only orientation of the calf in the birth canal remained significant (OR 2.14; 95% CI: 1.02–4.49; P = 0.044). Overall survival of calves with NE was good (45/58; 77.6%; 95% CI: 64.7–87.5); dam parity and being a twin was significantly associated with nonsurvival. Conclusions Calves born after dystocia, especially if malpresented, should be closely monitored for nursing behavior within the first 24 hours of life. Prognosis for survival is good, but supportive care might be required for several days.

Cerebrospinal Nematodiasis in 20 Camelids

Background Information about the clinical and clinicopathologic aspects of cerebrospinal nematodiasis (CN) in camelids is limited. Hypothesis Clinical and therapeutic variables will be identified as factors predictive of survival. Animals Client‐owned camelids suspected of having CN admitted to Purdue University between 1995 and 2015. Methods A retrospective study was performed. A diagnosis of CN was based on cerebrospinal fluid (CSF) eosinophilic pleocytosis or postmortem findings. Results Eleven alpacas and 9 llamas met the inclusion criteria. Seventy‐five percent of the camelids were male (27% castrated and 73% intact). Common clinical abnormalities included proprioceptive deficits (100% of animals), recumbency (55%), tachypnea (55%), and ataxia (40%). Among the 85% of treated animals, 100% received PO fenbendazole, and 88% received a nonsteroidal anti‐inflammatory drug. The survival rate to discharge was 45%. Plasma fibrinogen concentration, creatine kinase activity, and serum creatinine concentration were significantly higher in nonsurvivors. Blood eosinophil count, platelet count, and total CO 2 were significantly lower in nonsurvivors. Factors associated with survival were species, sex, absence of treatment with corticosteroids, and clinical improvement. There was no association between recumbency at admission and survival. A plasma fibrinogen concentration above >266 mg/dL was an excellent diagnostic test to predict survival in the presence of neurological signs or CSF eosinophilia. Conclusions Although prognosis for CN in camelids is guarded, presence of recumbency at admission is not predictive of nonsurvival. Male camelids and llamas appear more likely to die from CN. Corticosteroid treatment is contraindicated in animals diagnosed with CN.