Equine Neonates Research Articles

Tumor necrosis factor-α is transferred to equine neonates via colostrum but is not associated with their health status

We followed the hypothesis that equine neonates with reduced transfer of tumor necrosis factor-α (TNFα) are at increased risk of neonatal infection. We investigated TNFα concentrations in colostrum of healthy mares and blood of their neonates in a non-hospitalized population of Warmblood mares where delivery, neonatal adaptation and health was closely monitored by veterinarians. Concentration of TNFα and IgG was determined in colostrum respective milk and in neonatal blood collected immediately after delivery and 18 h thereafter in 97 foals that were assigned to groups failure of passive transfer (FPT; n = 31) and control (CON; n = 66) based on serum IgG concentration at 18 h of age. Foal health was assessed repeatedly during the first 24 h of life. Statistical analysis was done with p < 0.05 indicating significance. There were no significant differences between foal groups FPT and CON regarding age and parity of dams, gestation length (FPT 343 ± 10, CON 340 ± 8 days) and foal sex. Concentrations of TNFα in colostrum at birth and in foals at 18 h varied but did not differ between groups (colostrum FPT 6.1 ± 9.1, CON 9.9 ± 31.5 ng/ml; foal FPT 2.3 ± 5.9, CON 2.4 ± 5.3 ng/ml; n.s.). There was an increase in the mean serum TNFα concentration until 18 h in foals (n.s. between groups). Results of the present study confirm previous findings of TNFα transfer from the mare to the neonate via colostrum but do not suggest that transfer of TNFα via colostrum is important for protection of the neonate against infectious diseases.

Comparison of the broncoalveolar lavage fluid proteomics between foals and adult horses.

Neonates have different cellular composition in their bronchoalveolar lavage fluid (BALF) when compared to foals and adult horses; however, little is known about the non-cellular components of BALF. The objective of this study was to determine the proteomic composition of BALF in neonatal horses and to compare it to that of foals and adult horses. Bronchoalveolar lavage fluid samples of seven neonates (< 1 week age), four 5 to 7-week-old foals, and six adult horses were collected. Quantitative proteomics of the fluid was performed using tandem mass tag labeling followed by high resolution liquid chromatography tandem mass spectrometry and protein relative abundances were compared between groups using exact text. A total of 704 proteins were identified with gene ontology terms and were classified. Of these, 332 proteins were related to the immune system in neonates, foals, and adult horses. The most frequent molecular functions identified were binding and catalytic activity and the most common biological processes were cellular process, metabolic process, and biological regulation. There was a significant difference in the proteome of neonates when compared to foals and to adult horses. Neonates had less relative expression (FDR < 0.01) of many immune-related proteins, including immunoglobulins, proteins involved in the complement cascade, ferritin, BPI fold-containing family B member 1, and macrophage receptor MARCO. This is the first report of equine neonate BALF proteomics and reveals differential abundance of proteins when compared to BALF from adult horses. The lower relative abundance of immune-related proteins in neonates could contribute to their susceptibility to pulmonary infections.

Colostral transfer of tumor necrosis factor-α to neonates is not associated with their health status

Timely and adequate colostrum intake is vital for the equine neonate. In addition to immunoglobulins, colostrum contains bioactive substances. Tumor necrosis factor-α (TNF) has been suggested to help prevent neonatal infections (Secor et al., Vet Rec 2012;170:51). Transfer of TNF to neonates via colostrum was assessed in healthy mares (n=101) foaling in a veterinary clinic. Concentration of TNF (ELISA Equine TNF-α duo-set; R & D Systems) and IgG was determined in colostrum and neonatal blood immediately after delivery and 18h thereafter. Neonatal health was assessed via a modified sepsis score. Foals were assigned to two groups: failure of passive transfer (FPT; n=32) or control (C; n=66) based on serum IgG concentration below or above 0.8 g/l at 18 h of age. Three foals were excluded. Statistical analysis between groups was done by chi2 test or t-test (IBM SPSS statistics 27.0). Values are given as mean±SD. A p-value <0.05 was considered significant. Groups did not differ with regard to parity of dams (ns), gestation length (FPT 343±10, C 340±8 days, ns) and foal sex (ns). Premature lactation (milk running from >12h before parturition) which may reflect bacterial placentitis was noted in 9/32 and 5/66 dams of groups FPT and C, respectively (p<0.01), but no mare received treatment.All foals were born mature. Concentration of serum IgG in neonates differed between groups (FPT 4.9±1.8, C 13.4±4.5 g/l; p<0.001). No foals had detectable TNF in serum at birth (lower detection limit of assay: 2.1 pg/ml). In colostrum, TNF was detectable in 81% and 83% of dams in groups FPT and C, respectively (ns). In 34% and 54% of their foals, TNF was present at 18h (ns). Concentrations of TNF in colostrum at birth and in foals at 18h varied considerably but did not differ between groups (colostrum FPT 5968±9022, C 9980±31493 pg/ml, ns; foal FPT 2214±5851, C 2412±5327 pg/ml, ns). The sepsis score categorized 27 and 64 foals of groups FPT and C at 18h as normal, while 5 and 2 were slightly compromised respectively. From the 32 FPT and 66 C foals, 18 and 4 were treated with equine plasma (1l intravenously). None of the foals developed clinical signs of sepsis within the following days. The results demonstrate that TNF is transferred from the mare to the neonate via colostrum. The TNF blood concentration of a foal was not associated with its health status. An involvement of macrophage-secreted TNF in the morphogenesis of the mammary gland (Gouon-Evans et al., Breast Cancer Res 2002, 4:155-164) has to be considered in horses.

Antibiograms of field and hospital acquired equine neonatal bacterial fluid cultures in the Midwestern United States: 149 samples (2007‐2018)

Contemporary data reflecting local pathogens and their antibiograms is necessary to select empirical antimicrobial therapy for equine neonates. Describe bacterial isolates associated with equine neonatal infection and their antibiograms in the Midwestern United States. An increase in gram-positive infection and antibiotic resistance compared to previous literature was expected. Data from 149 fluid samples from 133 foals <30 days of age submitted for bacterial culture between January 2007 and December 2018. A retrospective evaluation of equine neonatal fluid cultures was performed. Fluid submission type, bacterial culture and antibiogram, empirical antibiotic treatment, and foal outcome was included. Isolate susceptibility to individual antimicrobials and combination protocols relevant to equine practice were recorded. The effect of recorded variables on foal survival was evaluated using Fisher's exact or chi-squared tests. Ninety bacterial isolates (78 aerobes and 12 anaerobes) were identified and gram-positive organisms predominated (n=50/90, 56%). Greater than 70% of aerobic isolates were susceptible to ampicillin, ceftiofur, chloramphenicol, trimethoprim/sulfamethoxazole, and all penicillin/aminopenicillin and aminoglycoside combinations. Seventy-seven (n=81/105) percent of foals survived. Survival was associated with a negative fluid culture and was not associated with empirical antimicrobial choice. Gram positive and anaerobic isolates associated with equine neonatal fluid cultures exceed that of previous reports. Historical empirical antimicrobial choices for equine neonatal infection in the Midwestern United States are supported by local antibiogram results.

Energy endocrine physiology, pathophysiology, and nutrition of the foal

Most homeostatic systems in the equine neonate should be functional during the transition from intra- to extrauterine life to ensure survival during this critical period. Endocrine maturation in the equine fetus occurs at different stages, with a majority taking place a few days prior to parturition and continuing after birth. Cortisol and thyroid hormones are good examples of endocrine and tissue interdependency. Cortisol promotes skeletal, respiratory, cardiovascular, thyroid gland, adrenomedullary, and pancreatic differentiation. Thyroid hormones are essential for cardiovascular, respiratory, neurologic, skeletal, adrenal, and pancreatic function. Hormonal imbalances at crucial stages of development or in response to disease can be detrimental to the newborn foal. Other endocrine factors, including growth hormone, glucagon, catecholamines, ghrelin, adipokines (adiponectin, leptin), and incretins, are equally important in energy homeostasis. This review provides information specific to nutrition and endocrine systems involved in energy homeostasis in foals, enhancing our understanding of equine neonatal physiology and pathophysiology and our ability to interpret clinical and laboratory findings, therefore improving therapies and prognosis.

Postnatal Dynamics of Circulating Steroid Hormones in Mule and Equine Neonates.

It is necessary to study hormonal patterns from mules to recognize alterations and neonatal maladaptation. Our objective was to evaluate concentrations of hormones in mule (n = 6) and equine foals (n = 6). Blood was collected at T0, 1, 6 and 12 h after birth. Hormone concentrations were evaluated using liquid chromatography tandem mass spectrometry. Effects of time, group and interactions and regression analysis were evaluated (p &lt; 0.05). There was a cubic and quadratic decline in mule and equine foals, respectively, for 3β,20α-dihydroxy-DHP. Mule foals were born with lower circulating 3β,20α-dihydroxy-DHP concentrations, which might be related to progestogen concentrations in mares with a hybrid placenta. Corticosterone and cortisol concentrations remained unchanged for the first hour post-foaling then declined in mule and equine foals (p &lt; 0.0001). Dehydroepiandrosterone was the main androgen present. There was a decrease in dihydrotestosterone at 12 h (p = 0.002). Differences in the temporal patterns of secretion within each steroid class, pregnanes, corticoids, and androgens, suggest they were derived from different tissue sources, presumptively the placenta, adrenals and gonads of the fetus/neonate, respectively. Mule and horse foals were born without evidence of testosterone secretion. For the first time, steroid hormone levels were measured in neonatal mules, and this will provide insight into neonatal physiology that differs from equine and allow us to gain an understanding of mules that have rarely been studied. Further studies are needed to elucidate the effects of hybrid pregnancies in the steroid endocrinology of neonates.

Comparison of insulin sensitivity between healthy neonatal foals and horses using minimal model analysis.

The equine neonate is considered to have impaired glucose tolerance due to delayed maturation of the pancreatic endocrine system. Few studies have investigated insulin sensitivity in newborn foals using dynamic testing methods. The objective of this study was to assess insulin sensitivity by comparing the insulin-modified frequently sampled intravenous glucose tolerance test (I-FSIGTT) between neonatal foals and adult horses. This study was performed on healthy neonatal foals (n = 12), 24 to 60 hours of age, and horses (n = 8), 3 to 14 years of age using dextrose (300 mg/kg IV) and insulin (0.02 IU/kg IV). Insulin sensitivity (SI), acute insulin response to glucose (AIRg), glucose effectiveness (Sg), and disposition index (DI) were calculated using minimal model analysis. Proxy measurements were calculated using fasting insulin and glucose concentrations. Nonparametric statistical methods were used for analysis and reported as median and interquartile range (IQR). SI was significantly higher in foals (18.3 L·min-1· μIU-1 [13.4–28.4]) compared to horses (0.9 L·min-1· μIU-1 [0.5–1.1]); (p < 0.0001). DI was higher in foals (12 × 103 [8 × 103−14 × 103]) compared to horses (4 × 102 [2 × 102−7 × 102]); (p < 0.0001). AIRg and Sg were not different between foals and horses. The modified insulin to glucose ratio (MIRG) was lower in foals (1.72 μIUinsulin2/10·L·mgglucose [1.43–2.68]) compared to horses (3.91 μIU insulin2/10·L·mgglucose [2.57–7.89]); (p = 0.009). The homeostasis model assessment of beta cell function (HOMA-BC%) was higher in horses (78.4% [43–116]) compared to foals (23.2% [17.8–42.2]); (p = 0.0096). Our results suggest that healthy neonatal foals are insulin sensitive in the first days of life, which contradicts current literature regarding the equine neonate. Newborn foals may be more insulin sensitive immediately after birth as an evolutionary adaptation to conserve energy during the transition to extrauterine life.

Serum amyloid A as an aid in diagnosing sepsis in equine neonates.

Sepsis is a significant cause of morbidity and mortality in neonatal foals, especially during the first 7days of life. Diagnosing sepsis in neonatal foals can be challenging because initial clinical signs are often ambiguous and non-specific. To determine if the major acute phase protein serum amyloid A (SAA) as measured by a point-of-care SAA testing device can be used as an evidence-based biomarker of sepsis. Retrospective cohort. Clinical diagnosis of sepsis based on positive bacterial blood culture or a positive sepsis score was obtained and compared to SAA values in a population of neonatal foals on a breeding farm and referral hospital during four consecutive foaling seasons. A rapid, point-of-care blood test was used to measure SAA concentrations in neonatal foals <36hours old that were clinically diagnosed as healthy, sick non-septic or septic. The septic foals (n=35) had a median SAA concentration (114µg/mL) that was significantly greater (P<.05) than that for foals in the sick non-septic (n=117, 1.5µg/mL) and healthy (n=245, 0µg/mL) groups. At a diagnostic threshold of 100µg/mL, the SAA test had a sensitivity of 52.9% (95% CI 36.5-68.9), specificity of 97.5% (95% CI 95.0-99.0), positive predictive value of 75.0% (95% CI 56.2-87.5), negative predictive value of 93.7% (95% CI 91.2-95.5), and a test accuracy of 92.1% (95% CI 88.2-95.0). The results of this study indicate that SAA is a useful aid in the diagnosis of sepsis in the neonatal foal.

Serum symmetric dimethylarginine concentration in healthy neonatal Thoroughbred foals.

Symmetric dimethylarginine (SDMA) is widely used in other species as a marker of renal dysfunction and is considered a more sensitive indicator of glomerular filtration rate than creatinine. Reference ranges are established in healthy adult horses (≤14μg/dL) and concentrations are increased in horses with acute kidney injury (median 32μg/dL; range 15-92). To establish the normal range of SDMA concentrations in neonatal Thoroughbreds. Cross-sectional. Blood samples were collected from Thoroughbred foals <36h old deemed healthy by physical examination. Exclusion criteria included foals from mares undergoing treatment for placentitis and foals that developed clinical disease or died/euthanised <2weeks from birth. Biochemistry and serum SDMA concentrations were obtained. Subjects included 120 foals. Median age was 13.5h (range 1.0-34.0). Median and 95% confidence interval for SDMA concentration was 69.0µg/dL (63.0, 75.0; range 35.0-376.0). A cut-off value of 168µg/dL would include 95% of individuals and is therefore suggested. Serum SDMA concentration was correlated with age (R=-.3, P=.003), creatinine concentration (R=.6, P≤.001) and urea concentration (R=.3, P=.002). Limitations include a small sample size, no consideration of subclinical disease and a short follow-up period. In equine neonates, SDMA concentration is higher than in adult horses, older foals and adults with acute kidney injury. Therefore, currently SDMA cannot be used as a marker of renal dysfunction in this age group. Further work is required to assess whether SDMA concentration is increased in neonates with renal disease and, if so, what cut-off should be used.

The enteroinsular axis during hospitalization in newborn foals

The enteroinsular axis (EIA) is an energy regulatory system that modulates insulin secretion through the release of enteroendocrine factors (incretins). Despite the importance of energy homeostasis in the equine neonate, information on the EIA in hospitalized foals is lacking. The goals of this study were to measure serum insulin and plasma incretin (glucose-dependent insulinotropic polypeptide [GIP], glucagon-like peptide-1 [GLP-1] and glucagon-like peptide-2 [GLP-2]) concentrations, to determine the insulin and incretin association, as well as their link to disease severity and outcome in hospitalized foals. A total of 102 newborn foals ≤72 h old were classified into hospitalized (n = 88) and healthy groups (n = 14). Hospitalized foals included septic (n = 55) and sick non-septic (SNS; n = 33) foals based on sepsis scores. Blood samples were collected over 72 h to measure serum insulin and plasma GIP, GLP-1 and GLP-2 concentrations using immunoassays. Data were analyzed by nonparametric methods and univariate logistic regression. At admission, serum glucose and insulin and plasma GIP were significantly lower in hospitalized and septic compared to healthy foals (P < 0.01), while plasma GLP-1 and GLP-2 concentrations were higher in hospitalized and septic foals than healthy and SNS foals, and decreased over time in septic foals (P < 0.05). As a percent of admission values, GLP-1 and GLP-2 concentrations dropped faster in healthy compared to hospitalized foals. Serum insulin concentrations were lower in hospitalized and septic non-survivors than survivors at admission (P < 0.01). Hospitalized foals with serum insulin < 5.8 µIU/mL, plasma GLP-1 >68.5 pM, and plasma GLP-2 >9 ng/mL within 24 h of admission were more likely to die (OR = 4.2; 95% CI = 1.1–16.1; OR = 13.5, 95% CI = 1.4–123.7; OR = 12.5, 95% CI = 1.6–97.6, respectively; P < 0.05). Low GIP together with increased GLP-1 and GLP-2 concentrations indicates that different mechanisms may be contributing to reduced insulin secretion in critically ill foals, including impaired intestinal production (GIP, proximal intestine) and pancreatic endocrine resistance to enhanced incretin secretion (GLP-1, GLP-2; distal intestine). These imbalances could contribute to energy dysregulation in the critically ill equine neonate.

Survival and racing performance after surgical treatment of rib fractures in foals.

To evaluate the short and long-term outcomes of foals treated surgically for fractured ribs and variables that may affect outcome. Retrospective. Seventy-three equine neonates with surgically repaired fractured ribs. Medical records were reviewed to include sex, breed, the side of thorax affected, number of ribs fractured, co-morbidities directly associated with rib fracture, and surgical technique used. Short-term outcome was defined as survival to discharge. Long-term outcome was whether or not they started a race. Race records of maternal siblings were obtained for comparison. Seventy-three neonates underwent surgery for fractured ribs. Fifty-seven neonates (78%) survived to discharge from the hospital. Rib fractures were more commonly observed in colts and in the left hemithorax (61% and 57%, respectively). Sex, side affected, number of ribs fractured, co-morbidities, number of ribs repaired, and surgical technique did not affect the short- or long-term outcomes. Thirty-five of 57 (61%) foals treated surgically for rib fractures that survived to discharge started a race compared to 173 of 257 (67%) of maternal siblings that raced. Short- and long-term outcome were not affected by co-morbidities, surgical technique, or number of fractured ribs. Neonates with surgically repaired fractured ribs had a good prognosis for survival and and those that survived had a similar chances of starting a race compared to maternal siblings.

Paratracheal air cyst in a foal

SummaryA 1‐day‐old American Paint Horse was presented for a large air‐filled mass along the ventral aspect of the neck. Bronchoscopy and oesophagoscopy revealed no sign of communication with the trachea or oesophagus. Radiographs and a computed tomography scan of the neck identified a communicating tract between the lumen of the cystic mass and mid‐trachea. The foal was systemically healthy at this initial presentation, and delayed removal of the cyst was recommended to allow further maturation of the foal prior to undergoing general anaesthesia. Upon discharge, the cyst continued to grow in size and became more fluid than air‐filled requiring repeat centesis and draining. The foal was then re‐presented at 3 weeks of age for surgical removal. In surgery, direct communication with the trachea was identified and ligated. Histopathology demonstrated that the cyst lining was composed of squamous epithelium with goblet cells and occasional ciliated cells. The location, morphological features and congenital presentation of the mass were consistent with a paratracheal air cyst (PAC). Surgical resection resulted in excellent functional and cosmetic outcome. Although not previously reported in horses, PAC should be included in the differential diagnosis of an air‐filled ventral neck mass in equine neonates. Complete surgical excision may result in a successful outcome.

Oxidative state in equine neonates: Anti- and pro-oxidants.

In newborns, exposure to the extrauterine environment with high oxygen tension and sudden pulmonary adaptation leads to an increase in reactive oxygen species (ROS). ROS have several physiological roles, which are essential for neonatal development, however, when unbalanced, these highly unstable molecules can cause cellular destabilisation, compromising vital processes. To characterise the oxidative status in healthy equine neonates, evaluating an indicator of lipid peroxidation and both enzymatic and nonenzymatic antioxidant systems, during the first week of life. Experimental cohort. Twenty-four foals were evaluated, with blood collections performed at 5minutes, 12, 72 and 168hours after birth. The degree of lipid peroxidation was quantified using Thiobarbituric Acid Reactive Substances (TBARS). Superoxide dismutase (SOD) and glutathione peroxidase (GPx) enzymatic activities, and total, conjugated and unconjugated serum bilirubin levels were also analysed. Comparisons were performed using ANOVA followed by a Tukey's test. Additionally, dependent variables were also evaluated with Pearson's correlation tests. Higher GPx activity was observed at 12 and 72hours when compared to 5minutes. An increase in TBARS levels was found at 5minutes after birth, followed by a decrease at 72hours and stabilisation through subsequent moments until 168hours after birth. No differences were observed in SOD activity when comparing the four time points. Bilirubin concentrations were lower at 5minutes after birth and total and unconjugated bilirubin increased at 12hours and decreased between 72 and 168hours after birth. Lipid peroxidation at birth was high, suggesting an increase in ROS levels relating to physiological events in neonatal adaptation. Antioxidant systems, involving unconjugated bilirubin and GPx, were activated and these biomolecules act concomitantly to reduce ROS levels, thus maintaining oxidative homeostasis. Overall, our results suggest a pro-oxidant balance during the first 168hours after birth in equine neonates.

Ultrasonography in neonatal foals: Depiction and measurement of the kidneys

Aim of the study was to describe the echotexture and dimensions of the kidneys including the renal pelvis in neonatal foals using transabdominal sonography. In the course of a preliminary examination, sonographic examinations of the kidneys of 10 dead newborn foals were performed in order to determine their localization, measurement parameters, and echotexture. In subsequent necropsies, the kidneys were measured and the obtained values were compared with the sonographic measurements. A high level of agreement between the both measurement values could be demonstrated. In the main examination, 57 1- to 14-day old foals of different breeds were examined. The intercostal spaces and the fossa paralumbalis of both body halves were scanned in longitudinal direction and the topography and echotexture of the kidneys were evaluated using a standardized sonographic examination procedure. The length and width of the organ as well as the extent of the renal pelvis were measured during the same procedure. The obtained measurement values were analyzed comparatively under consideration of different breeds. The renal capsule was identified sonographically by the depiction of a fine hyperechogenic line. The renal cortex itself proved to be echogenic in the ultrasonographic image and the renal medulla hypoechogenic. The renal pelvis exhibited a hyperechogenic sound image. The mean length and width of the left kidney amounted to 7.1 ± 1.4 cm and 4.2 ± 0.7 cm, respectively. The right kidney measured 6.7 ± 1.4 cm and 3.9 ± 0.7 cm in mean length and width. The measurement of the left renal pelvis resulted in mean values of 1.3 ± 0.7 cm in length and 0.7 ± 0.4 cm in in width. Mean length and width of the right renal pelvis amounted to 1.3 ± 0.6 cm and 0.6 ± 0.4 cm, respectively. The renal pelvis displayed an anechogenic lumen on the left and right sides in 24.6 % and 64.3 % of the foals, respectively. The comparison of the measurement values under consideration of different breeds showed that body weight of the equine neonates did not exhibit a correlation with kidney size. Transabdominal sonography is a reliable diagnostic tool for the evaluation of kidneys in neonatal foals. The description of physiological renal echotexture and dimensions serves to identify pathological conditions.

Sonographic topography of abdominal organs and structures in equine neonates

The study aimed to present a systematic and standardized examination for neonatal foals' abdominal sonography and to describe physiological topographic conditions of some abdominal organs and structures. A standardized sonographic examination of the abdomen was performed in 57 foals in left and right lateral recumbency. Left and right intercostal spaces as well as the ventral abdomen which was divided into 6 segments (left, middle and right cranial, left middle and right caudal abdomen) were examined. The locations, in which the various organs could be found, were described. Furthermore death foals were examined sonographically followed by a necropsy to verify the organs' topography. A standardized systematic examination for abdominal ultrasonography in neonatal foals could be developed and the extension of some abdominal organs could be described. The umbilical vein is localized in the middle cranial segment, the urachus in the middle caudal segment. The umbilical arteries start in the middle caudal segment und spread into the left and right one. The bladder is constantly found in the caudal aspect of the abdomen and extents, depending on its filling, in the middle or in the left and right segments as well. The right kidney is located in the 15th to 17th intercostal space (ICS), the left kidney in the 16th and 17th ICS. The spleen can be visualized in the left 10th to 16th ICS and often in the left cranial abdominal segment. The liver is found in the middle and right cranial segment and the right 16th to 17th ICS and in the left 7th ICS. The stomach is located in the left and middle cranial segment and in the left 9th to 11th ICS, the duodenum constantly in the right 12th ICS. The jejunum can be found in the left caudal and the middle abdominal segments. Caecum is in the right 15th ICS to the fossa paralumbalis and the colon in both right segments and the middle caudal one. By examining the neonatal foals' abdomen in a systematic ultrasonographic way the most important abdominal organs can be visualized.

Short-term outcome and risk factors for post-operative complications following umbilical resection in 82 foals (2004-2016).

Umbilical remnant infection and patent urachus are an important cause of morbidity for the equine neonate. Left untreated, fatal complications can develop. Identifying risk factors for post-operative complications after surgery are important for estimating prognosis. To identify risk factors associated with post-operative complications in foals undergoing umbilical remnant resection due to patent and/or infected umbilical remnants. Retrospective case series. Foals undergoing umbilical remnant resection due to patent urachus or infected remnants at the Marion duPont Scott Equine Medical Center from 2004 to 2016 were included in the study. Data were obtained from medical records and associations between outcomes and post-operative complications, and pre or intraoperative clinical variables were assessed using bivariable and multivariable analyses. Eighty-two foals underwent umbilical remnant resection of which 73 (89.0%) survived to discharge. The urachus was the most commonly affected structure being patent and/or infected in 84.1% of cases. Concurrent diseases were present in 60.6% of foals prior to surgery, with diarrhoea and septic arthritis being most common. The presence of preoperative septic arthritis and/or physitis were significantly associated with nonsurvival (OR 33; 95% confidence interval 1.1-985.2; P = 0.04). Longer anaesthesia time (OR 1.4; 95% confidence interval 1.1-1.7; P = 0.02) and failure of passive transfer of immunoglobulins (OR 5.9; 95% confidence interval 1.2-29.04; P = 0.03) were associated with increased odds for post-operative complications. It is not known if medical treatment alone would have been successful in foals that did not receive preoperative medical treatment. Overall survival is high after surgical excision of umbilical remnants. The presence of preoperative septic arthritis and/or physitis was associated with decreased survival and failure of passive transfer of immunoglobulins and longer anaesthesia times were associated with increased odds for post-operative complications.

Ultrasonography of the umbilical remnant in foals

Pathologies of the umbilical remnant are relatively common in equine neonates both as primary entities and as consequences of prematurity, dystocia and septicaemia. Early diagnosis is fundamental to improving the...

Differences in third metacarpal trabecular microarchitecture between the parasagittal groove and condyle at birth and in adult racehorses.

The aetiology of equine metacarpal condylar fractures is not completely understood and a developmental cause has been postulated. To investigate the subchondral bone trabecular microarchitecture of the lateral parasagittal groove and condyle in equine neonates and its adaptation with maturation and athletic activity. Ex vivo observational study. Distal metacarpi of neonates, yearlings and adult racehorses (n = 24) were harvested. Dorsal and palmar frontal histological sections, containing the lateral parasagittal groove and condyle, were studied. The sections were digitalised and subchondral trabecular bone quantity and quality parameters and trabecular orientation in the frontal plane were measured. Trabecular spacing and length were greater (P = 0.004 and P = 0.0005 respectively) whereas bone fraction, trabecular number and connectivity were all lower (P = 0.0004, P = 0.0001 and P = 0.001 respectively) in the lateral parasagittal groove compared with the condyle in neonatal foals. Trabecular thickness and bone fraction increased with age in racehorses and trabecular spacing decreased. The predominant trabecular orientation had a consistent pattern in neonates and it changed with maturity and the cumulative effect of racing at all the ROIs except for the palmar lateral parasagittal groove that retained a more 'immature' pattern. Samples were investigated in 2D. 3D processing could have provided more information. Already at birth there are striking differences in the subchondral bone trabecular microarchitecture between the lateral parasagittal groove and condyle in foals. Adaptation of trabeculae is confirmed with maturity in racehorses, with the greatest adaptation measured in bone quantity parameters. The trabecular orientation had a unique and more immature orientation pattern in the lateral palmar parasagittal grooves in adult racehorses and may reflect a weaker structure at this site.

Emergency care of the equine neonate in the field

James SW Prutton BSc (Hons) BVSc DipACVIM DipECEIM MRCVS, Equine Medicine Specialist, Liphook Equine Hospital, outlines the assessment process

Evaluation of updated sepsis scoring systems and systemic inflammatory response syndrome criteria and their association with sepsis in equine neonates.

BackgroundThe original equine sepsis score provided a method of identifying foals with sepsis. New variables associated with sepsis have been evaluated, but the sepsis score has not been updated.ObjectivesTo evaluate the sensitivity and specificity of 2 updated sepsis scores and the systemic inflammatory response syndrome (SIRS) criteria in regard to detecting sepsis in foals.AnimalsTwo‐hundred and seventy‐three ill foals and 25 healthy control foals.MethodsHistorical, physical examination, and clinicopathologic findings were used to calculate the original sepsis score and 2 updated sepsis scores. SIRS criteria were also evaluated. Sepsis scores and positive SIRS scores were statistically compared to foals with sepsis.ResultsOne‐hundred and twenty‐six foals were septic and 147 sick‐nonseptic. The original and updated sepsis scores were significantly higher in septic foals as compared to sick‐nonseptic and healthy foals. The sensitivity and specificity of the updated sepsis scores to predict sepsis were not significantly better than those of the original sepsis score. One‐hundred and twenty‐seven of 273 (46.5%) foals met the original SIRS criteria and 88/273 (32%) foals met the equine neonatal SIRS criteria. The original SIRS criteria had similar sensitivity and specificity for predicting sepsis as did the 3 sepsis scores in our study.Conclusions and Clinical ImportanceThe updated sepsis scores did not provide improved ability in predicting sepsis. Fulfilling the original SIRS criteria provided similar sensitivity and specificity in predicting sepsis as the modified sepsis score and might serve as a diagnostic aid in identifying foals at risk for sepsis.