Failure of passive transfer in foals: incidence and outcome on four studs in New South Wales

Objective To determine the regional incidence and effectiveness of treatment of failure of passive transfer (FPT) in foals. Design A study of disease incidence. Animals Eighty-eight foals and 57 mares from four studs in the practice area of the Rural Veterinary Centre were tested. Procedure Foals were tested for their serum IgG and total serum protein (TSP) concentration within the first 72 hours of life. Colostrum was collected from mares and specific gravity determined. FPT and partial failure of passive transfer (PFPT) of immunoglobulins was diagnosed when serum IgG concentrations were < 4 g/L and 4 to 8 g/L respectively. Owners of foals diagnosed with FPT were offered treatment with 1 to 2 L plasma (TSP > 70 g/L); 9 (64%) of the affected foals were treated. Results Fourteen foals (16%) had FPT whereas 15 (17%) had PFPT. There were significant differences between the mean TSP concentration in foals with FPT (42.6 ± 4.2 g/L), PFPT (48.1 ± 3.9 g/L) and those acquiring adequate passive immunity (58.9 ± 5.5 g/L) (P < 0.01). Sixteen (29%) mares had pre-suck colostral specific gravity < 1.060 and 12 (71%) foals raised by these mares had FPT or PFPT. The incidence of severe disease (categorised by a sepsis score > 11, positive culture of bacteria from blood or disease requiring hospitalisation) in all foals in the first 2 months of life was 10%. However, none of the nine foals with FPT that received plasma experienced severe disease. In contrast, foals with PFPT had an increased susceptibility to severe disease (P < 0.001) when compared with normal foals. Conclusion Treatment of foals with FPT may reduce the subsequent incidence of severe disease. Pre-suck colostral specific gravity and foal TSP may be used to predict the likelihood of FPT and PFPT. Even though the number of foals studied is small the results highlight the importance of optimal management practices in reducing the incidence of FPT and disease associated with this process.     

Thromboelastography in healthy, sick non-septic and septic neonatal foals

Objectives To evaluate citrated recalcified thromboelastography (TEG) in healthy newborn foals, and to determine intra‐assay, inter‐individual and intra‐individual (at 12 h, 24 h and 7 days after birth) variations. Additionally, to compare TEG variables, haematological values and conventional coagulation profiles from healthy, sick non‐septic, and septic foals. Design Prospective study. Methods The study group comprised 18 healthy, 15 sick non‐septic and 17 septic foals. Two citrated (3.2%; 1 : 9 anticoagulant : blood ratio) blood samples were submitted for haemostatic evaluation using a TEG analyser and conventional coagulation profile. TEG values (R time (R), K time (K), angle (α), maximum amplitude (MA) and G value (G)), complete blood count (CBC) and conventional coagulation profile (prothrombin time (PT), activated partial thromboplastin time (aPTT), fibrinogen concentration (Fib) and antithrombin (AT)) were evaluated. Signalment, presenting complaint, sepsis scores, blood culture results and outcome were taken from the medical records of the sick foals. Results Mean values ± SD for TEG variables in healthy neonatal foals were: R = 11.82 ± 5.35 min, K = 3.06 ± 1.34 min, α= 51.19 ± 12.66 degrees, MA = 55.06 ± 6.67 mm and G = 6361 ± 1700 dyn/cm². Mean coefficients of variation for intra‐assay/inter‐individual/intra‐individual in healthy foals were: R = 3.5/45.2/43.1%; K = 5.3/58.7/28.7%; α= 1.5/24.7/11.9%; MA = 0.3/12.1/6.1%; G = 1.6/26.7/14.7%. Septic foals had significantly greater α, MA and G values than sick non‐septic foals, and significantly greater MA and G than healthy foals, changes that are consistent with hypercoagulability. Weak correlations were detected between TEG variables and haematological or haemostatic values. Conclusions TEG could be used to provide additional information about the haemostatic system in equine neonates.     

Serum protein reference values in foals during the first year of life: comparison of chemical and electrophoretic methods

Normal reference values for serum proteins of foals from birth to 1 year of age have been established. Chemical and electrophoretic/refractometric methods for total protein, albumin, total globulin and Albumin/Globulin (A/G ratio) have also been compared. The biuret total protein method and Bromcresol Green (BCG) method on the Technicon SMA 12/60 autoanalyzer were used and compared with total protein determined via refractometry and albumin determined by Cellulose Acetate (CA) electrophoresis/densitometry. Globulin and A/G ratios were calculated from the chemical method data and compared with that obtained electrophoretically. Total protein, albumin, total globulins and A/G ratios all were in agreement at all sample times studied. Data on the subfractionation of serum globulins via CA electrophoresis is also presented. Wide variations in alpha and beta globulin levels were noted among the foal sera early in life. As a result, two distinct populations of foals with respect to both globulin content and A/G ratio were identified. One of these populations (Group A) appeared to have obtained passive immunity more slowly than the other (Group B) animals. Comparison of these data with clinical cases of foals in which failure of passive transfer was a part suggests that the A/G ratio may be useful in assessing adequate colostral antibody levels in the newborn foal.     

Parenteral nutrition in neonatal foals: clinical description, complications and outcome in 53 foals (1995-2005)

This retrospective study describes the use of and complications associated with parenteral nutrition (PN) administration to 53 equine neonates at the University of California Veterinary Medical Teaching Hospital. Medical records were examined and information obtained on signalment, physical examination, clinical diagnosis, outcome, total hospitalization time, insulin administration, microbiology culture results, other complications (i.e. thrombophlebitis) and necropsy findings. Complete blood count and serum biochemistry analytes, venous blood gas, serum electrolyte and glucose concentrations, and blood lactate concentration results were compared before and during PN administration in all foals. Seventeen foals (32%) developed hypertriglyceridemia (>200mg/dL). Triglyceride concentrations >200mg/dL were significantly (P=0.049) associated with non-survival. Forty-seven foals (89%) developed hyperglycemia (blood glucose >120mg/dL) and eight (15%) developed catheter-related complications (thrombosis or local sepsis). Packed cell volume, total protein, creatinine, blood urea nitrogen, and sorbitol dehydrogenase concentrations decreased while foals were on PN, while serum chloride concentration increased. This study highlighted that hypertriglyceridemia during the acute phase of neonatal illness may be detrimental to outcome, and that the safety of lipid-containing solutions in foals warrants further study.     

A comparison of total calcium,corrected calcium,and ionized calcium concentrations as indicators of calcium homeostasis among hypoalbuminemic dogs requiring intensive care

Objective – (1) To evaluate whether total calcium (tCa) correlates with ionized calcium (iCa) in hypoalbuminemic dogs; (2) to evaluate whether calcium adjusted for albumin (Alb), or total protein (TP), or both accurately predict iCa concentrations and hence can be used to monitor calcium homeostasis in critically ill hypoalbuminemic dogs; and (3) to evaluate factors associated with any potential discrepancy in calcium classification between corrected total and ionized values. Design – Prospective observational clinical study. Setting – Small animal intensive care unit in a veterinary medical teaching hospital. Animals – Twenty‐eight client‐owned dogs with hypoalbuminemia. Interventions – None. Measurements and Main Results – iCa was determined using ion‐specific electrode methodology, on heparinized plasma. The tCa concentration was adjusted for Alb and TP using published equations. In total 29% (8/28) of the hypoalbuminemic, critically ill dogs in this study were hypocalcemic at intensive care unit admission, as determined by iCa measurement. Corrected calcium values failed to accurately classify calcium status in 67.9% and 64.3% of cases, according to whether the Alb‐adjusted or TP‐adjusted values, respectively, were used. The sensitivity and specificity of the tCa to evaluate hypocalcemia was 100% and 47%, respectively. The sensitivity and specificity of the correction formulae were 37.5% and 79% for the Alb‐adjusted values and 37.5% and 74% for TP‐adjusted values. tCa overestimated the presence of hypocalcemia and underestimated the presence of normocalcemia, while corrected calcium values overestimated the presence of normocalcemia and underestimated the presence of hypocalcemia. Conclusions – Calcium homeostasis in hypoalbuminemic critically ill dogs should be evaluated by iCa concentrations rather than tCa or calcium adjusted for Alb or TP. Given that tCa has 100% sensitivity for detecting hypocalcemia in this population it is recommended that all hypoalbuminemic and critically ill patients with low tCa should be evaluated with an iCa measurement.     

Association of hyperlactatemia with age,diagnosis, and survival in equine neonates

Objective – To investigate the association between blood lactate concentration, measured at admission and following 12–36 hours of treatment, and age, diagnosis, and survival in neonatal foals. Design – Retrospective, observational study. Setting – Two equine referral hospitals. Animals – One hundred and twelve foals ≤96 hours of age were included. Interventions – Arterial or venous blood samples were obtained from all foals at admission and surviving foals at 12–36 hours. Measurements – The lactate concentration (LAC) was recorded at 2 time points: admission (LAC‐Admission) and 12–36 hours following treatment (LAC‐24 hours). Main Results – LAC decreased by 0.05 mmol/L for each increased hour of age at presentation. Premature/dysmature foals demonstrated increased odds of nonsurvival of 55% for each 1 mmol/L increase in LAC‐Admission while foals with major diagnoses of neonatal encephalopathy (NE), enteritis and ‘Other’ had increased odds of nonsurvival of 52%, 113%, and 247%, respectively, for each 1.0 mmol/L increase in LAC. Blood‐culture positive foals had significantly lower LAC than blood culture negative foals. LAC‐Admission and LAC‐24 hours were significantly larger in nonsurviving foals. LAC‐Admission of >6.9 mmol/L and LAC‐24 hours >3.2 mmol/L, respectively, correctly classified 85.6% and 94.1% of cases as survivors or nonsurvivors. No differences were found when the 24‐hour change in LAC was investigated in terms of outcome, age at admission, or major diagnosis; however, LAC‐24 hours remained significantly associated with survival. Conclusions – Admission or persistent hyperlactatemia is associated with a nonsurvival. Younger foals, premature/dysmature foals, and foals with neonatal encephalopathy had the largest LAC.     

Clinical and prognostic significance of radiographic pattern, distribution, and severity of thoracic radiographic changes in neonatal foals

A total of 207 thoracic radiographs obtained from 128 foals were evaluated to assess the impact of pulmonary radiographic pattern, distribution, and severity of pulmonary changes on short-term survival of neonatal foals. The association between selected clinical variables and the radiographic manifestation of neonatal respiratory disease was also investigated. The evaluation of interstitial and alveolar-interstitial radiographic patterns within the caudodorsal, caudoventral, and cranioventral lung regions proved to be highly reliable between viewers in the study. A diagnosis of systemic inflammatory response syndrome was related to increased pulmonary infiltrates within the caudodorsal lung region. Dyspneic foals had more extensive pulmonary infiltrates within the cranioventral lung, advanced respiratory disease, and lower survival rates. A fibrinogen concentration >400 mg/dL was associated with increased cranioventral radiographic abnormalities. In addition, tachypnea most consistently related to diffuse (caudodorsal, caudoventral, and cranioventral) pulmonary changes. Neutropenia, milk reflux from the nares, upper airway pathology, abnormal respiratory sounds, failure of transfer of passive immunity (IgG concentration <400 mg/dL), immaturity, or fever, however, were not related to radiographic pattern, distribution, or severity of radiographic changes. Sixty-five percent of foals with radiographic pulmonary disease were discharged alive from our referral hospital. Concurrent caudodorsal and caudoventral radiographic disease was most frequently observed in this foal population. Increased caudodorsal radiographic scores retained statistical significance as a prognostic indicator for nonsurvival in a multiple stepwise logistic regression analysis.     

Diseases in neonatal foals. Part 1: The 30 day incidence of disease and the effect of prophylactic antimicrobial drug treatment during the first three days post partum

Reasons for performing study: Neonatal diseases have been grouped and analysed but up‐to‐date statistically significant information about the incidence and prevalence of diseases in foals is limited. Since the 1950s it has been a common management practice to administer a 3 day course of antimicrobial drugs to neonatal foals. This was shown to significantly reduce the incidence of infections (Platt 1977). Since then management practices have improved and it is widely believed that prophylactic antimicrobial drugs are no longer necessary in foal rearing. Objectives: To determine the 30 day incidences or prevalences (depending on case definition) of various diseases and conditions in the neonatal foal and ascertain the influence of a prophylactic 3 day treatment on the frequency of infections. Methods: The population consisted of Thoroughbred foals born on stud farms in the Newmarket (UK) area in 2005 (n = 1031). Depending on the stud farm's practice in the use of prophylactic antimicrobial drugs, 2 groups of newborn foals (treated and untreated) were identified and followed for 30 days. Results: The 30 day incidences of infectious diseases under study were between 0.2% (osteomyelitis) and 5.85% (systemic disease with diarrhoea). The overall incidence for ‘total infectious diseases’ was 8.27%. The most commonly observed noninfectious condition was limb deformities (12.11% of all foals). There was no significant difference in the incidence of infectious diseases between the 2 groups. Conclusion: Infectious diseases are still an important problem in neonatal foals requiring further investigation as to which factors other than antimicrobial prophylaxis are relevant for disease prevention. Potential relevance: The results provide an up‐to‐date overview about the frequencies of various neonatal foal diseases. They do not support the traditional prophylactic use of antimicrobials to prevent infectious diseases in healthy newborn foals. However, it should be noted that this study was not a randomised controlled trial and therefore does not provide the strongest possible evidence for this conclusion.     

Multiple meningiomas: clinical, radiological, surgical, and pathological findings with outcome in four cats

The present report describes the clinical signs, magnetic resonance imaging (MRI) findings, surgical procedure, pathological findings and follow-up in four cats with multiple meningiomas; three castrated male and one spayed female domestic shorthair indoor cats, ranging in age from 11 to 14 years. In three of four cats, clinical signs at presentation were suggestive of a focal lesion. Three cats had two meningiomas and one had four meningiomas. Most of the tumours were supratentorial, one arose from the tentorium and one was infratentorial. The duration of presenting signs before surgery ranged from 10 days to 11 months. Postoperative MRI revealed complete gross tumour removal in three cases. In one cat with two cranial fossa meningiomas, subtotal excision with a small basal remnant (2 x 2 mm) of the ventral part of one meningioma lying on the floor of the skull, was observed. Based on histopathological architecture, six tumours revealed features of a transitional subtype meningioma, and four of a meningotheliomatous meningioma. In each cat, the multiple meningiomas were all assigned to the same histopathological group. The preoperative presenting signs had resolved by the follow-up examinations 4 weeks after surgery in two cats. Long-term follow-up evaluation revealed that surgically-induced or exacerbated neurological deficits in two cats had completely or almost completely resolved within 8 weeks of surgery. All patients are still alive 12 to 21 months after surgery and no clinical signs of recurrence could be detected at that time.     

Acute kidney injury in dogs: Etiology,clinical and clinicopathologic findings,prognostic markers,and outcome

BackgroundAcute kidney injury (AKI) is a common, potentially fatal condition.ObjectivesTo characterize the etiologies, clinical and clinicopathologic findings, hospitalization period, and outcome of dogs with AKI and to identify markers of negative prognosis.AnimalsTwo hundred forty‐nine client‐own dogs diagnosed with AKI and hospitalized at a veterinary teaching hospital.MethodsRetrospective study. Search of medical records for dogs with AKI.ResultsCommon clinical signs included lethargy (225/249, 90%), anorexia (206/249, 83%), and vomiting (168/249, 68%). Etiologies included ischemic/inflammatory (144/249, 58%), infectious (19/249, 8%), nephrotoxicosis (14/249, 6%), or other (13/249, 5%). Hospital‐acquired AKI was diagnosed in 9% (23/249) of the dogs. Median presentation and peak serum creatinine (sCr) concentrations were 4 mg/dL (range, 1.1‐37.9) and 4.6 mg/dL (range, 1.1‐43.1), respectively. Dogs were classified to AKI grades as follows: Grade I, 6 (2%), Grade II, 38 (15%), Grade III, 89 (36%), Grade IV, 77 (31%), and Grade V, 39 (16%). One hundred and sixty‐four (66%) dogs survived. There was a positive association between death and AKI grade (P = .009). The case fatality rate was higher among dogs with anuria compared with dogs without anuria (50% vs 28%, respectively; odds ratio [95% confidence interval]: 2.5 [1.39‐4.6]; P = .002). Forty‐seven (18.8%) dogs underwent hemodialysis, of which 60% survived.Conclusion and Clinical ImportanceTwo‐thirds of dogs with AKI survived. Hospital‐acquired AKI was common. The severity of AKI, as reflected by presence of anuria, AKI grade, and other body organs involvement, was associated with the outcome.     

Causes of cardiopulmonary arrest, resuscitation management, and functional outcome in dogs and cats surviving cardiopulmonary arrest

Objective: To describe the functional outcome of canine and feline survivors of cardiopulmonary arrest (CPA) and the clinical characteristics surrounding their resuscitation. Design: Retrospective study. Setting: Veterinary teaching hospital. Animals: Client‐owned dogs (15) and cats (3) with CPA. Interventions: None. Measurements and main results: Eighteen animals were identified to have survived to discharge following CPA. Cardiopulmonary arrest was associated with anesthesia with or without pre‐existing disease in 10 animals, cardiovascular collapse in 5 animals, and chronic disease with an imposed stress in 3 animals. All CPAs were witnessed in the hospital. The most common initial rhythm at CPA was asystole (72%). Return of spontaneous circulation (ROSC) was achieved in less than 15 minutes from the onset of cardiopulmonary cerebral resuscitation (CPCR) in all animals. No animals had a recurrence of CPA after the initial CPA. Animals were of a wide range of ages (0.5–16 years) and breeds. Two animals were neurologically abnormal at discharge, one of which was normal at 2 months following CPA. Conclusions: A good functional recovery after CPCR was documented in the small number of CPA survivors presented in this study. This may be due to the reversible nature of their inciting cause of CPA, early detections of CPA (‘witnessed’), and/or the animal's underlying normal health status.