Exercising upper respiratory videoendoscopic findings of 50 competition draught horses with abnormal respiratory noise and/or poor performance.

BACKGROUND: Upper respiratory tract (URT) endoscopy at rest is commonly used to evaluate competition draught horses with URT conditions. Overground endoscopy might be preferred for draught horse URT evaluation as it allows the horses to be driven with harness, overcheck and cart-load under similar conditions to those experienced in the show ring where airway conditions are most prominent. OBJECTIVE: To describe the exercising URT findings of competition draught horses with abnormal respiratory noise and/or poor performance. STUDY DESIGN: Case series. METHODS: Medical records of competition draught horses undergoing overground endoscopic evaluation between January 2013 and January 2018 with a presenting complaint of abnormal respiratory noise and/or poor performance were reviewed. Video recordings of resting and overground endoscopy were evaluated in all horses. Spearman's rank correlation coefficient was calculated between laryngeal function at rest and at exercise. RESULTS: Fifty competition draught horses were examined. Thirteen had previously undergone URT surgery. There was significant correlation between resting and exercising laryngeal function (ρ = 0.77, P<0.01). Abnormalities were detected in 46 horses and included arytenoid cartilage collapse (n = 31), vocal fold collapse (n = 27), palatal dysfunction (n = 14), epiglottic disorders (n = 11), dynamic laryngeal collapse (n = 1), rostral deviation of the palatopharyngeal arch (n = 3) and medial deviation of the aryepiglottic folds (n = 16). The majority of horses had a complex of abnormalities (n = 31) or required exercising examination for identification (n = 41). Incidental upper oesophageal incompetence was observed in nine horses. MAIN LIMITATIONS: Retrospective collection of data. CONCLUSIONS: Overground endoscopic evaluation was a useful technique for identifying URT disorders in competition draught horses. The spectrum of upper airway conditions identified in exercising draught horses supports the use of overground endoscopy as a diagnostic technique and could influence treatment considerations. The Summary is available in Portuguese - see Supporting Information.

Reproductive careers of Thoroughbred broodmares before and after surgical correction of ≥360 degree large colon volvulus.

BACKGROUND: Limited data exist describing broodmare longevity and reproductive efficiency after surgical correction of ≥360 degree large colon volvulus (° LCV). OBJECTIVES: Compare career duration and foals delivered for broodmares before and after ≥360° LCV surgery. STUDY DESIGN: Retrospective case series. METHODS: Broodmares registered with The Jockey Club that had surgical correction of ≥360° LCV and survived to hospital discharge at Rood and Riddle Equine Hospital from 1 January 2000 to 31 December 2015 were included. Information was collected from the hospital's medical data base and The Jockey Club produce records about the mares' reproductive careers. Data were evaluated using parametric and nonparametric tests, P≤0.05. RESULTS: Mares that were bred but never foaled prior to surgery (n = 19) had shorter careers (mean ± standard deviation [s.d.]), 4.4 ± 4.5 years, and fewer foals, 3.1 ± 3.3, compared with mares that delivered ≥1 foal before surgery (n = 565), 10.4 ± 4.5 years and 7.4 ± 3.4 foals, respectively, P<0.001. Broodmares that delivered foals before surgery produced more foals in the years before surgery, 4.8 ± 3.0, than after surgery, 2.6 ± 2.4, P<0.001, and had longer breeding careers, 5.9 ± 3.8 vs. 4.5 ± 3.3 years before compared with after surgery, P<0.001. No significant differences in career length or number of foals delivered were detected for mares with a single compared with multiple LCV surgeries. Mares that were 3-11 years old at the time of surgery had significantly more foals after surgery compared with mares ≥12 years old, P<0.001, as expected. MAIN LIMITATIONS: Retrospective collection of data. CONCLUSIONS: Broodmares had productive careers following surgery for ≥360° LCV that were largely influenced by the mares' age at the time of surgery.

Duration of disease influences survival to discharge of Thoroughbred mares with surgically treated large colon volvulus.

REASONS FOR PERFORMING STUDY: Large colon volvulus results in strangulating obstruction requiring surgical treatment. Duration of this disease prior to surgical treatment is likely to influence survival directly. OBJECTIVES: The primary objective of this study was to evaluate the influence of duration of large colon volvulus on patient survival to discharge. Relationships between other factors and survival following large colon volvulus were also examined. STUDY DESIGN: Retrospective case analysis. METHODS: Medical records of Thoroughbred mares aged ≥2 years undergoing surgical treatment for large colon volvulus between 1 March 1986 and 28 February 2011 were reviewed. Multivariable logistic regression was used to identify influence of duration and other factors on survival to discharge. RESULTS: Within the study period, 1039 surgeries were performed to correct large colon volvulus in 896 Thoroughbred mares. Median duration of colic signs prior to admission was 2 h (interquartile range [IQR] 1-4 h). Median time from admission to anaesthetic induction was 25 min (IQR 15-45 min). Median surgical time was 70 min (IQR 55-85 min). Primary surgical treatment was simple correction of the large colon volvulus followed by replacement of the colon. The overall survival to discharge was 88%. The final model identified risk factors significantly associated with survival and included colic duration prior to admission, packed cell volume at admission, surgery length, duration of hypotension while under anaesthesia, heart rate 48 h post operatively, post operative manure consistency and days hospitalised. CONCLUSIONS: Duration of colic prior to admission was statistically associated with patient survival to discharge. Other factors significantly associated with survival in mares with large colon volvulus were related to disease severity and degree of colonic compromise. Mares with large colon volvulus have a good prognosis for recovery with early referral and prompt surgical treatment.

Detection of bacteraemia and host response in healthy neonatal foals.

REASONS FOR PERFORMING THE STUDY: Neonatal sepsis is a common problem in foals and is a primary cause of death in the post natal period. Transient bacteraemia and subsequent host responses have not been described in the equine neonate. OBJECTIVES: The primary objective of this study was to determine if transient bacteraemia occurs in foals within the first 72 h of life. Additional objectives included description of bacterial organisms associated with transient bacteraemia and concurrent cytokine gene expression in healthy foals. STUDY DESIGN: Prospective observational study in healthy foals. METHODS: Blood was aseptically collected for bacterial culture from observed spontaneously born foals at birth and 1, 2, 3, 4, 8, 12, 24, 48 and 72 h following birth. Samples taken at birth, 4, 12, 24, 48 and 72 h were analysed for interferon gamma (IFNγ), interleukin (IL)-1, IL-2, IL-6, IL-8, IL-10, IL-18 and monocyte chemotactic protein 1 (MCP1) cytokine gene expression quantified by RT-PCR. RESULTS: Bacteria were cultured from 9 of 70 samples submitted for blood culture. The positive samples were from 4 of the 7 foals, all of which remained healthy throughout and subsequent to the study. All positive blood cultures were from blood samples obtained at 12 h of age or earlier and IL-10 elevation coincided with positive blood cultures in healthy foals. Cytokine gene expression fluctuated with age. CONCLUSIONS: Positive blood cultures suggest transient bacteraemia may occur in healthy foals early in the post natal period. Age corrected normal values may be necessary to interpret cytokine concentration in diseased populations.

Prairie rattlesnake envenomation in 27 New World camelids.

BACKGROUND: Morbidity and case fatality from rattlesnake envenomation is regionally specific because of variability in relative toxicity of the species of snake encountered. A previous report of rattlesnake envenomation in New World camelids (NWC) from the western coastal United States documented high case fatality rates and guarded prognosis for survival. HYPOTHESIS/OBJECTIVES: To describe clinical findings, treatments, and outcome of NWC with prairie rattlesnake (Crotalus viridis viridis) envenomation in the Rocky Mountain region of the United States. ANIMALS: Twenty-seven NWC admitted to the Colorado State University Veterinary Teaching Hospital for evaluation of acute rattlesnake envenomation between 1992 and 2012. METHODS: Medical records of NWC evaluated for rattlesnake envenomation as coded by the attending clinician and identified by a database search were reviewed retrospectively. Month of admission, signalment, area of bite, clinical and clinicopathologic data, treatments, and outcome were recorded. RESULTS: Twenty-five llamas and 2 alpacas were admitted for envenomation. Llamas were overrepresented compared to hospital caseload. The face was the most common site of envenomation, observed in 96% of recorded cases. Presenting clinical signs included fever, tachypnea, tachycardia, and respiratory distress. Nine animals required a tracheotomy. Median hospitalization time was 3 days and overall survival rate was 69%. CONCLUSIONS AND CLINICAL IMPORTANCE: Case fatality rate for prairie rattlesnake envenomation in NWC was lower than that reported in the Western coastal region of the United States and similar to that reported for prairie rattlesnake envenomation in horses.

Milk thistle and its derivative compounds: a review of opportunities for treatment of liver disease.

Milk thistle extracts have been used as a "liver tonic" for centuries. In recent years, silibinin, the active ingredient in milk thistle extracts, has been studied both in vitro and in vivo to evaluate the beneficial effects in hepatic disease. Silibinin increases antioxidant concentrations and improves outcomes in hepatic diseases resulting from oxidant injury. Silibinin treatment has been associated with protection against hepatic toxins, and also has resulted in decreased hepatic inflammation and fibrosis. Limited information currently is available regarding silibinin use in veterinary medicine. Future study is justified to evaluate dose, kinetics, and treatment effects in domestic animals.

Evaluation of a veterinary glucometer for use in horses.

BACKGROUND: Glucose assessment and regulation are important factors in the treatment of hospitalized horses and foals. HYPOTHESIS/OBJECTIVES: The purpose of this study was to compare glucose measurement by a veterinary glucometer, adjusted by code for use in horses and foals, to a reference chemistry analyzer. It was hypothesized that the veterinary glucometer and reference analyzer would yield similar results and that interpretation of glucose values obtained from a veterinary glucometer would result in clinically appropriate decisions. ANIMALS: Fifty blood samples from adult horses and 50 blood samples from neonatal foals admitted to the Colorado State University Veterinary Hospital or Equine Reproduction Laboratory for evaluation. METHODS: Glucose concentrations from fresh whole blood samples were evaluated in duplicate with a veterinary glucometer and these values were compared with those obtained with a reference plasma chemistry analyzer. The accuracy of glucometer measurement was evaluated with a Clarke error grid. RESULTS: The veterinary glucometer accurately measured whole blood glucose concentrations in both horses and foals when compared with a reference plasma chemistry analyzer. Nearly 97% of the glucometer values obtained in this study would have resulted in appropriate clinical decisions based on the Clarke error grid analysis. CONCLUSIONS AND CLINICAL IMPORTANCE: The veterinary glucometer evaluated has potential utility for point-of-care whole blood glucose evaluation in both horses and foals.

Arterial blood gas parameters of normal foals born at 1500 metres elevation.

REASONS FOR PERFORMING STUDY: Arterial blood gas analysis is widely accepted as a diagnostic tool to assess respiratory function in neonates. To the authors' knowledge, there are no published reports of arterial blood gas parameters in normal neonatal foals at altitude. OBJECTIVE: To provide information on arterial blood gas parameters of normal foals born at 1500 m elevation (Fort Collins, Colorado) in the first 48 h post partum. HYPOTHESIS: Foals born at 1500 m will have lower PaO2 and PaCO2 than foals born at sea level due to low inspired oxygen and compensatory hyperventilation occurring at altitude. METHODS: Sixteen foals were studied. Arterial blood gas analysis was performed within 1 h of foaling and subsequent samples were evaluated at 3, 6, 12, 24 and 48 h post partum. Data were compared to those previously reported in healthy foals born near sea level. RESULTS: Mean PaO2 was 53.0 mmHg (7.06 kPa) within 1 h of foaling, rising to 67.5 mmHg (9.00 kPa) at 48 h post partum. PaCO2 was 44.1 mmHg (5.88 kPa) within one hour of foaling, falling to 38.3 mmHg (5.11 kPa) at 48 h. Both PaO2 and PaCO2 were significantly lower in foals born at 1500 m elevation than those near sea level at several time points during the first 48 h. CONCLUSIONS AND POTENTIAL RELEVANCE: Foals at 1500 m elevation undergo hypobaric hypoxia and compensatory hyperventilation in the first 48 h. Altitude specific normal arterial blood values are an important reference for veterinarians providing critical care to equine neonates.