Accurate quantitative analysis of equine insulin in blood samples is critical for assessing hyperinsulinemia in horses. Although there are various laboratory methods for evaluating equine serum insulin, different immunoassays show significant discrepancies between the determined insulin concentrations and are often not comparable. The aim of this study was to evaluate the Immulite® 1000 chemiluminescent immunoassay (CLIA) to establish independent laboratory and assay-specific cut values to provide an accurate diagnosis of hyperinsulinemia in horses. Thus, the analytical and clinical performance of Immulite® 1000 CLIA in terms of precision (intra- and inter-assay coefficient of variance, CV) and recovery upon dilution were evaluated and compared with radioimmunoassay (RIA), which has been previously validated for use in horses.Archived serum samples (n = 106) from six Quarter horse mares enrolled in the glucose phase of a Frequently Sampled Insulin and Glucose Test (FSIGT) study were used to measure blood insulin.The Immulite® 1000 CLIA had good precision with acceptable intra- and inter-assay CVs, adequate recovery on dilution, and a strong correlation with the RIA (r = 0.974, P < 0.0001), with constant bias resulting in consistently lower values.On this basis, the Immulite® 1000 Insulin Assay is valid for measuring equine serum insulin for diagnostic and monitoring purposes when cut values are appropriately adjusted.
Abstract Introduction The COVID-19 pandemic caused by the novel coronavirus SARS-CoV-2 has put an unprecedented burden on global healthcare, including detrimental implications for the volume and provision of surgical services. The aim of this audit was to assess if the planned surgical cancer care (both diagnostic for possible cancer, and treatment of known cancer) during this period of widespread community and hospital based COVID-19 infection resulted in patients acquiring symptomatic COVID-19 as a consequence of their surgical admission, and if so, what the impact on patients was. Methods A prospective audit of all patients undergoing elective cancer surgery in Greater Manchester operated on between 01/05/2020 and 31/06/2020 was undertaken after the introduction of specific peri operative COVID safety measures across Greater Manchester cancer surgical cells. The COVID related outcomes for all cancer patients operated on in Greater Manchester were recorded. Results Of the 1501 patients undergoing surgery, one (<0.1%) was diagnosed with COVID-19 in hospital within 14 days of surgery. This patient did not require admission to critical care due to post-operative COVID-19 diagnosis, and there was no associated mortality related to post-operative COVID-19 infection. Conclusion The use of peri operative COVID-19 infection prevention strategies has allowed for the safe continuation of elective cancer surgery during this pandemic in all surgical units, without significant additional COVID-19 related morbidity or mortality.
Background Pituitary pars intermedia dysfunction ( PPID ) is common in older horses. Objectives To determine diagnosis frequency, prognostic factors, long‐term survival, and owner satisfaction with treatment. Animals Medical records from horses diagnosed with PPID , 1993–2004. Methods A retrospective cohort design with data collected from the Veterinary Medical Data Base ( VMDB ) and a cohort of 3 VTH s. Proportional accessions, annual incidence, and demographics were compared for all accessions. During the same period, a subset of medical records (n = 44) was extracted and owners (n = 34) contacted to obtain long‐term follow‐up information. Results Diagnoses of PPID were reported for 217 horses that presented to VTH s and were reported to the VMDB . Proportional diagnosis increased from 0.25/1,000 in 1993 to 3.72/1,000 in 2002. For 44 horses included in the follow‐up study, the most commons signs were hirsutism (84%) and laminitis (50%). Of 34 horse owners contacted, the average time from onset of signs to diagnosis was 180 days. Improvement in ≥ 1 signs, 2 months after diagnosis, was reported by 9/22 (41%) of horse owners. Clinical signs and clinicopathologic data were not associated with survival, and 50% of horses were alive 4.6 years after diagnosis. Cause of death among horses (15/20; 85%) was euthanasia, and 11/15 (73%) were euthanized because of conditions associated with PPID . Most horse owners (28/29; 97%) said they would treat a second horse for PPID . Conclusion and Clinical Importance PPID was diagnosed with increasing frequency, and 50% of horses survived 4.5 years after diagnosis. Owners were satisfied with their horses' quality of life and would treat a second horse if diagnosed.
Equine protozoal myeloencephalitis (EPM) due to Sarcocystis neurona infection is 1 of the most common neurologic diseases in horses in the United States. The mechanisms by which most horses resist disease, as well as the possible mechanisms by which the immune system may be suppressed in horses that develop EPM, are not known. Therefore, the objectives of this study were to determine whether horses experimentally infected with S. neurona developed suppressed immune responses. Thirteen horses that were negative for S. neurona antibodies in serum and cerebrospinal fluid (CSF) were randomly assigned to control (n = 5) or infected (n = 8) treatment groups. Neurologic exams and cerebrospinal fluid analyses were performed prior to, and following, S. neurona infection. Prior to, and at multiple time points following infection, immune parameters were determined. All 8 S. neurona–infected horses developed clinical signs consistent with EPM, and had S. neurona antibodies in the serum and CSF. Both infected and control horses had increased percentages (P < 0.05) of B cells at 28 days postinfection. Infected horses had significantly decreased (P < 0.05) proliferation responses as measured by thymidine incorporation to nonspecific mitogens phorbol myristate acetate (PMA) and ionomycin (I) as soon as 2 days postinfection.
Sarcocystis neurona is the most common cause of Equine Protozoal Myeloencephalitis (EPM), affecting 0.5-1% horses in the United States during their lifetimes. The objective of this study was to evaluate the equine immune responses in an experimentally induced Sarcocystis neurona infection model. Neurologic parameters were recorded prior to and throughout the 70-day study by blinded investigators. Recombinant SnSAG1 ELISA for serum and CSF were used to confirm and track disease progression. All experimentally infected horses displayed neurologic signs after infection. Neutrophils, monocytes, and lymphocytes from infected horses displayed significantly delayed apoptosis at some time points. Cell proliferation was significantly increased in S. neurona-infected horses when stimulated nonspecifically with PMA/I but significantly decreased when stimulated with S. neurona compared to controls. Collectively, our results suggest that horses experimentally infected with S. neurona manifest impaired antigen specific response to S. neurona, which could be a function of altered antigen presentation, lack of antigen recognition, or both.
Abstract Objective —To assess antiulcerogenic properties of 3 dietary oils. Animals —8 healthy adult mares. Procedure —A protocol to induce gastric ulcers was used and included 240 mL of water plus corn oil, refined rice bran oil, or crude rice bran oil administered each day for 6 weeks according to a 4 × 4 Latin square randomized crossover design with 5-week washout intervals. A 7-day alternating feed deprivation period was included between weeks 5 and 6. Omeprazole was administered daily for the last 14 days of each washout interval. Endoscopic examinations of the stomach were performed at 0, 5, and 6 weeks, and the number (0 to 4 scale) and severity (0 to 5 scale) of ulcers were scored. Gastric fluid was collected at 0 and 5 weeks. Results —Median body weight significantly increased by 29 kg (range, 10 to 50 kg). Mean ± SE gastric fluid pH significantly decreased from 4.9 ± 0.4 to 3.1 ± 0.3 over 5 weeks, and total volatile fatty acid concentration significantly decreased over time. Mean ± SE severity of nonglandular ulcers significantly increased from 0.4 ± 0.1 to 1.2 ± 0.2 over 5 weeks. Nonglandular ulcers significantly increased in number (mean ± SE, 1.3 ± 0.2 to 3.0 ± 0.2) and severity (mean ± SE, 1.2 ± 0.2 to 2.6 ± 0.2) during the 7-day alternating feed deprivation period. No effects of treatment were detected. Conclusions and Clinical Relevance —In this model dietary oils did not prevent gastric ulcers from forming in the nonglandular portion of the stomach of horses. ( Am J Vet Res 2005;66:2006–2011)
Summary Bodyweights (BW) of 39 horses, competing in a 3‐day event, were measured the evening before the endurance test (BW 1 ), after phase D (BW 2 ) and the next morning before stadium jumping (BW 3 ). Plasma sodium concentration [Na 1 ] was measured the evening before and after phase C of the endurance test [Na 2 ]. Total body water (TBW 1 ) was calculated using the formula (BW1 (kg) × 0.66 l/kg) and water loss (WL) was calculated as [(BW 1 – BW x ) X 0.9]. Cation balance (CB), the exchangeable cation concentration, was calculated using the formula [(TBW 1 (1) X Na 1 ) ‐ (TBW 2 (1)] X Na 2 ). The decrease in BW and TBW averaged 17.4 ± 1.0 kg and 15.6 ± 0.8 litres respectively (mean ± s.e.m.) during the endurance test and remained decreased 9.2 ± 1.0 kg (BW) and 8.3 ± 1.0 litres (TBW) for 18 to 24 h after competition. Plasma sodium concentration after phase C of the endurance test (141.2 ± 0.3 mmol/l) was greater than resting values (138.8 ± 0.2 mmol/l), resulting in a net decrease in CB (‐1601.1 ± 171.7 mmol). Significant water and electrolyte losses occur in horses competing in the endurance test of a 3‐day event and these fluid losses persist for 18–24 h after this phase of competition.
Abstract Objective —To compare the effects of hydrochloric acid (HCl) and various concentrations of volatile fatty acids (VFAs) on tissue bioelectric properties of equine stomach nonglandular (NG) mucosa. Sample Population —Gastric tissues obtained from 48 adult horses. Procedures —NG gastric mucosa was studied by use of Ussing chambers. Short-circuit current (Isc) and potential difference (PD) were measured and electrical resistance (R) and conductance calculated for tissues after addition of HCl and VFAs (5, 10, 20, and 40mM) in normal Ringer's solution (NRS). Results —Mucosa exposed to HCl in NRS (pH of 1.5 and, to a lesser extent, 4.0) had a significant decrease in Isc, PD, and R, whereas tissues exposed to acetic acid at a pH of < 4.0, propionic and butyric acids at a pH of ≤ 4.0, and valeric acid at a pH of ≤ 7.0 induced a concentration-dependent effect on reduction in these same values. Values for Isc returned to baseline (recovery of sodium transport) after addition of calcium carbonate in tissues exposed to all concentrations of VFAs except the higher concentrations of valeric acid at a pH of ≤ 4.0. Histologic examination revealed cell swelling in the mucosal layers below and adjacent to the stratum corneum in tissues exposed to HCl and VFAs at a pH of ≤ 4.0. Conclusions and Clinical Relevance —The VFAs, especially acetic acid, in the presence of HCl at a pH of ≤ 4.0 appear to be important in the pathogenesis of NG mucosal ulcers in horses.
