Evaluation of Transmittance and Reflectance Pulse Oximetry in a Canine Model of Hypotension and Desaturation

Ten, anesthetized dogs were instrumented with three pulse oximeter probes; two lingual transmittance probes and one rectal reflective probe. Arterial oxygen desaturation was produced by decreasing the inspired oxygen concentration. Hypotension was produced with an infusion of nitroprusside. Simultaneous pulse oximeter readings (SpO₂) were compared to co-oximeter measured arterial saturation (SaO₂) collected over a range of SaO₂ (50–100%) and mean arterial pressures (40–100mmHg). Each of the monitors and means of evaluating SpO₂ studied provided accurate SpO₂ measurements over a range of mean arterial pressure from 40–100mmHg. All of the monitors tested tended to overestimate the SaO₂ when the arterial saturation was less than 70%.     

Effect of 5 cm of Water Positive End-Expiratory Pressure on Arterial Oxygen Tension in Dogs During and After Thoracotomy

Thoracotomy in dogs often is associated with lower than expected arterial oxygen tensions (PaO₂). Pulmonary collapse from opening the thoracic cavity is likely to be responsible for decreased PaO₂ during thoracotomy. To examine whether positive end-expiratory pressure (PEEP) is beneficial to dogs undergoing thoracotomy, PaO₂ and hemoglobin saturation (SaO₂) were measured in dogs randomly assigned to receive 5 cm of H₂O PEEP (n = 7) or no PEEP (n = 9). During surgery in both groups of dogs, PaO₂ progressively decreased ( P < .001), but the decrease in PaO₂ was significantly less in the PEEP group ( P = .027). In both groups, PaO₂ did not decrease enough to have a substantial effect on SaO₂. Furthermore, application of PEEP during thoracotomy did not prevent moderate hypoxemia after surgery and discontinuation of PEEP. Application of 5 cm of H₂O PEEP seems to attenuate the decrease in PaO₂ observed in dogs undergoing thoracotomy, but routine application of PEEP does not seem justified. ©     

Pulse Oximetry For Estimation Of Oxygenation In Dogs With Experimental Pneumothorax

The purpose of this study was the evaluation of pulse oximetry for estimating the oxygen saturation of hemoglobin (S_pO₂) in dogs with pneumothorax. Values for measured by pulse oximetry with transducers on the tongues and toes of six dogs were compared with saturation values (S_aO₂) computed from arterial oxygen tensions (P_aO₂) during experimentally induced pneumothorax (30,45, and 60 ml/kg of ambient air in the pleural space). Values for S_pO₂, S_aO₂, and P_aO₂ decreased with increasing volume of air. Compared to computed S_aO₂ values, S_pO₂ values obtained from the tongue tended to be less variable than those obtained from the toe, but both locations gave valuable information. Pulse oximetry appears to be a useful, relatively inexpensive method of estimating hemoglobin saturation in dogs with experimentally induced pneumothorax, and it appears to have clinical application in management of critical or traumartized dogs.     

Energy Expenditure in 104 Postoperative and Traumatically Injured Dogs with Indirect Calorimetry

Apparent restihg energy expenditure (AREE) and respiratory quotient (RQ) were determined by open flow indirect calorimetry in a group of 104 apparently resting, critically ill, postoperative and severely traumatized dogs. The evaluations were conducted in a calm, temperature-controlled environment after at least a 12-hour fast. Subjects were allowed to acclimilate to the monitoring equipment prior to beginning the study. The clinical patients were compared to a group of 20 clinically normal, apparently resting, client owned dogs (NC). The data was also compared to published normals (NP) for energy expenditure of apparently resting dogs. Measurements were indexed to actual body weight in kilograms (BW) as well as to metabolic body size(BW^0.75). Measurements of VO₂ (VO₂/kg and VO₂/kg^0.75) and VCO₂ (VCO₂/kg and VCO₂/kg^0.75) were used to calculate the RQ and the AREE. Critically ill, postperative and severely lower RQ values AREE/kg or AREE/kg^0.75 (p=0.39). The PO&T dogs did exhibit significantly lower RQ values (p<0.0001) than either the (NC) or (NP) groups. Measured AREE of the PO&T dogs was significantly less than a calcualted value using the illness/injury/infection energy requirement (IER), (p<0.0001). Energy expenditure in typical trauma and postoperative patients may commonly be overstimated by the IER method. Conclusion: The AREE of critically ill, postoperative and severly trumatized dogs was not higher than healthy dogs as has been previously suggested in the literature.     

Practicality, Usefulness, and Limits of Pulse Oximetry in Critical Small Animal Patients

Pulse oximetry holds the promise of wide application for monitoring and assessing pulmonary function in small animal patients. Although the saturation as read by pulse oximetry (SpO2) has previously been shown to be accurate in healthy dogs, its accuracy and usefulness have not been demonstrated in critical small animal patients. The present study assessed the accuracy and usefulness of a pulse oximeter (Ohmeda Biox 3740, Ohmeda, Louisville, CO) in a small animal intensive care unit. The instrument yielded readings in 48 of 51 attempts in 33 animals (25 dogs, 8 cats). Criteria were developed to reject spurious readings; when these criteria were applied, the actual calculated SaO2 differed from the SpO2 by O.26 +2.2%, with a correlation of 0.87 (p<0.0001). The 95% confidence interval was +4.4%, comparable to the accepted level in humans. No ill effects from SpO2 were apparent in the patients, and the instrument was useful in monitoring the progress of critical animals. However, uncritical use of the oximeter could have led to gross patient mismanagement, as SpO2 readings as much as 29% different from SaO2 were sometimes obtained.     

PRACTICALITY, USEFULNESS, AND LIMITS OF END-TIDAL CARBON DIOXIDE MONITORING IN CRITICAL SMALL ANIMAL PATIENTS

End-tidal monitors for measuring carbon dioxide (CO₂) have become widely available for clinical use in the last two decades. This non-invasive technology has been previously evaluated in anesthetized veterinary patients, but its accuracy has not been assessed in critical patients. We investigated the usefulness and limits of end-tidal CO₂ monitoring in two populations of critical small animal patients: spontaneously breathing dogs and mechanically ventilated patients with healthy and damaged lungs. In analyzing samples from 43 spontaneously breathing dogs and 34 ventilated patients (28 dogs and six cats), the end-tidal CO₂ was generally lower than pCO₂. The predictive value for hypoventilation was excellent in both populations (100%). The linear correlation of the end-tidal CO₂ and arterial pCO₂ in non-panting dogs with healthy lungs was 0.84 (p<0.0001), and the 95% confidence interval (CI) of the difference was ± 3.2 mm Hg. However, the measures were uncorrelated in panting dogs (r=0.37, p=0.27), and the 95% CI was ± 13.37 mm Hg. Furthermore, where multiple samples could be obtained in individual patients, the r values and differences of end-tidal compared to arterial pCO₂ varied unpredictably. These variations did not appear to be predicted by patient factors such as lung disease. We conclude that the end-tidal CO₂ monitor is clinically useful for detecting hypoventilation and monitoring apnea, but it should be supplemented with arterial pCO₂ determinations if it is important to obtain accurate pCO₂ measures.     

A Comparison of 2 Pluse Oximeters in Dogs

Readings from 2 veterinary pulse oximeters (SDI Vet-Ox #4402 and Nellcor N-20V) were compared in 6 isoflurane-anesthetized dogs. Simultaneous readings Of S_p0₂were recorded from 2 sites (toe and ear) over a range of inspired oxygen concentrations (15-100%), and compared to directly measured S_aO₂ readings. Greater variability of readings was obtained from the Vet-Ox, which failed to give readings 25% of the time. The bias (mean S_aO₂-S_p0₂) and precision (SD of bias) were calculated from the data for each oximeter. For the Vet-Ox, bias (precision) from the toe was +4.O (5.2) and from the ear +1.7 (2.2). The bias (precision) for N-20V readings from the toe was +1.6 (1.5) and from the ear +0.7 (1.5). Generally, both oximeters tended to underestimate S_aO₂; however, both overestimated at the lowest P_a0₂ values. Pearscn cowelation coeefficients were 0.81 for the Vet-Ox and 0.94 for the N-20V for the combined data, including value from probes placed on the toe and ear at all inspired oxygen concentrations. In the two locatiom from which readings were obtained, the 2 units performed quite differently.     

A Comparison of Arterial and Lingual Venous Blood Gases in Anethetized Dogs

The purpose of this study was to determine whether lingual vanous blood gas samples reflect arterial acid-base gas status in anethetized dogs. Heparinized blood samples were drawn simultaneously from the lingual vein and a peripheral artery in 50 anestheized dogs that were clinical surgical patients, as well as from four experimental dogs in which hemorrahaic shock was being studied. Blood pH, oxygen tension (PO₂), and bicarbonate (HCO_3-)) from the two sources in clinical patients showed significant liner correlation, although arterial PO₂)(PaO₂)) tended to be approximately 110mm Hg higher than lingual venous PO₂). During hemorrahgic shock, however, PaO₂) and PaCO₂) were significantly different from lingual venous PO₂) and PCO₂), Lingula venous blood gas analysis may be useful in assessing acid-base and blood gas status in routline cases, but should not be relied upon in dogs with low cardiac output or poor perfusion.     

Changes in Cardiopulmonary Variables and Platelet Count During Anesthesia for Total Hip Replacement in Dogs

Changes in cardiopulmonary function and platelet count were determined in 22 dogs of various breeds that underwent total hip replacement with cemented femoral prostheses. In 11 dogs (group I) polymethylmethacrylate (PMMA) was inserted without venting the reamed and lavaged femoral canal. In a second group of 11 dogs (group II) a urethral catheter (ID: approximately 2.7 mm) was placed into the medullary cavity before the insertion of PMMA. The application of PMMA resulted in a decrease in end-tidal carbon dioxide tension (PETco₂) until 5 minutes after insertion of bone cement. Increases in arterial to end-tidal pCO₂ gradient [P(a-ET)co₂] and physiological dead space (V_D/V_T) were recorded between 2 minutes before and 5 minutes after insertion of PMMA in 12 dogs. A significant decrease in platelet count occurred in both groups of dogs. Decreases in arterial pO₂ (Pao₂), arterial/alveolar oxygen tension ratio (Pao₂/PAo₂), and percent O₂ saturation of hemoglobin in arterial blood (Sao₂) were not statistically significant. No significant differences could be detected between data obtained from both groups of dogs. An increase in femoral intramedullary pressure caused by the insertion of PMMA and subsequent pulmonary microembolism by medullary contents has been considered the most likely cause for changes in pulmonary function. The lack of statistically significant differences in cardiopulmonary variables and platelet count between the two groups of dogs could have been related to inefficient pressure reduction by the method used.     

Pharmacokinetic studies of theophylline in dogs

The pharmacokinetics of theophylline were investigated in dogs following intravenous, single oral, and multiple oral doses of aminophylline. Mean half-life ( t _1/2) of theophylline following single intravenous administration was 5.7 h and the apparent specific volume of distribution ( V'd area) was 0.82 litre/kg. The bioavailability of theophylline was high (91%) following oral administration of aminophylline tablets and the absorption half-life ( t _{1/2 ab}) was 0.4 h.
Theophylline plasma concentrations observed following repeated oral administration of aminophylline tablets were somewhat greater than predicted. This suggests that theophylline plasma concentrations should be monitored and the dosage regimen individually adjusted in critically ill animals.     

Evaluation of intraocular and partial CO2 pressure in dogs anesthetized with propofol

The effects of propofol on intraocular pressure (IOP) and end tidal CO₂ (ETCO₂) were studied because an elevation in the latter may alter IOP. Twenty dogs were divided into two groups (G1 and G2). G1 dogs were induced with 10 mg/kg (IV) of propofol followed by a 0.4 mg/kg/min continuous infusion of the same agent diluted in a 0.2% dextrose solution for 1 h. G(CAPS) 2 dogs served as the control group, where only dextrose solution was administered, under the same time intervals as in G1. Applanation tonometry (Tono-Pen) was used to determine IOP and ETCO₂ as a method to determine partial CO₂ pressure. Measurements were taken every 15 min for 1 h, with M1 occurring immediately before IV administration. IOP and ETCO₂ were not statistically significant in either groups. Based on the results, it may be concluded that propofol does not alter IOP and ETCO₂.     

Evaluation of accuracy of pulse oximetry in newborn calves

In human medicine, pulse oximetry is widely used to measure non-invasively and accurately the percentage of oxygen saturation of arterial haemoglobin (SpO(2)). Recently, pulse oximetry has been used in calves, but its accuracy has not been evaluated in newborn calves. The purpose of this study was to evaluate the accuracy of a pulse oximeter in newborn calves by comparing SpO(2) with arterial oxyhaemoglobin saturation (SaO(2)) obtained by use of a blood gas analyser. Fifty-five newborn calves were investigated from birth to 20 days old. Pulse oximetry readings and arterial blood samples were performed 5, 15, 30, 45, 60 min, 2, 3, 6, 12, 24 h and 1 and 3 weeks after birth. The transmission-type sensors of the pulse oximeter were fixed at the recommended site in the bovine species (at the base of the calf tail, where the skin had been shaved and was not pigmented) and arterial blood samples were withdrawn from the subclavian artery and analysed for SaO(2). Five-hundred paired data of SaO(2) and mean SpO(2)(mSpO(2)) were collected. Linear regression of the pooled data indicated a highly significant correlation of mSpO(2) with SaO(2) (r = 0.87;P< 0.001; mSpO(2) = 15.8 + 0.84 SaO(2)). The overall data bias value was positive (+2.1%), which indicated that the pulse oximeter tended to overestimate the SaO(2). The bias value for each SaO(2) category tended to become higher for lower ranges of SaO(2). Precision was also lower when SaO(2) values were low. The lower the SaO(2) value, the higher the positive bias (overestimation) and the lower the precision. These results suggest that pulse oximetry provides a relatively accurate non-invasive, immediate and portable method to monitor SaO(2) and to evaluate objectively the pulmonary function effectiveness in newborn calves during their adaptation to extra-uterine life.     

Nitric Oxide Response in Critically III Dogs

Alterations in nitric oxide (NO)production may play a role in critical illness. Total serum nitrate/nitrite concentrations [SNN (uM/L)], the stable metabolites of NO, have been used as an indirect measure of NO in people, with increased concentrations reported in cases of critical illness. The relationship of nitric oxide (NO) to criticalillness in dgos is unknown. We tested the hypothesis that critically ill intensive care unit (ICU) canine illness in dogs is unknown. We tested the hypothesis that critically ill intesive care unit (ICU) canine patients would have increased SNN as compared to healthy dogs and non-critically ill dogs. An organ failure index score (OFI) was assigned to dogs admitted to the ICU to evaluate trends between disease severtiy and SNN. Critically ill dogs had significantly (p < 0.05) higher SNN (median 10.53) as compared to non-critically ill dogs (median 2.3) and healthy dogs (median 1.92). Critically ill dogs with the most severe disease (as based on OFI) had higher SNN concentrations. Survival of critically ill dogs with SNN of > 15 upon ICU admission (12% survival) was significantly less than survival of critically ill dogs with SNN ≤ 15 (91%) survival).l (Vet. Emerg. & Crit. Care, 9: 195–202, 1999)     

Thyroid Hormone Concentrations in Dogs With Chronic Weight Loss, With Special Reference to Cancer Cachexia

Serum concentrations of thyroxine (T₄), 3,5,3'-triiodothyronine (T₃), free thyroxine (fT₄), and free 3,5,3'-triiodothyronine (fT₃) were compared between tumor-bearing dogs (with and without chronic weight loss) and non—tumor-bearing dogs (with and without chronic weight loss) (n = 83). Serum T₄, T₃, and fT₃ concentrations were lower ( P < .05) in dogs with weight loss, whether or not they were tumor-bearing, than in dogs without weight loss. Serum fT₄ concentrations did not vary among the groups. Serum albumin concentrations were lower ( P < .05) in cachectic dogs than in dogs not experiencing weight loss, regardless of their tumor-bearing status. Percentage of weight loss was found to be associated ( P < .05) with T₄, T₃, and fT₃ concentrations. It appears that the low thyroid hormone concentrations are related to either an abnormal nutritional state or to the severity of illness, rather than to a tumor-related phenomenon.     

A step towards effect-site target-controlled infusion with propofol in dogs: a ke0 for propofol

Target-controlled infusion (TCI) anesthesia using target effect-site concentration rather than plasma concentration provides less drug consumption, safer anesthesia, less undesired side effects and improved animal welfare. The aim of this study was to calculate the constant that converts propofol plasma into effect-site concentration ( k _e0) in dogs, and to implement it in a TCI system and compare it with the effect on the central nervous system (CNS). All dogs were subjected to general anesthesia using propofol. Fourteen dogs were used as the pilot group to calculate k _e0, using the t _peak method. Fourteen dogs were used as the test group to test and validate the model. R ugloop ii ^® software was used to drive the propofol syringe pump and to collect data from S/5 Datex monitor and cerebral state monitor. The calculated k _e0 was incorporated in an existing pharmacokinetic model (Beths Model). The relationship between propofol effect site concentrations and anesthetic planes, and propofol plasma and effect-site concentrations was compared using Pearson's correlation analysis. Average t _peak was 3.1 min resulting in a k _e0 of 0.7230 min⁻¹. The test group showed a positive correlation between anesthetic planes and propofol effect-site concentration ( R  = 0.69; P <  0.0001). This study proposes a k _e0 for propofol with results that demonstrated a good adequacy for the pharmacokinetic model and the measured effect. The use of this k _e0 will allow an easier propofol titration according to the anesthetic depth, which may lead to a reduction in propofol consumption and less undesired side effects usually associated to high propofol concentrations in dogs.     

Pharmacokinetics of sulphadimidine in normal and febrile dogs

Pharmacokinetic parameters which describe the distribution and elimination of sulphadimidine were determined in normal dogs and dogs in which fever was produced by an intravenous injection of escherichia and staphylococcal species of bacteria. Sulphadimidine was injected as a single intravenous bolus at the dose of 100 mg/kg and the kinetics of the drug were described in terms of the bi-exponential expression: C_p = Ae ^{-α t} + Be ^{-β t} . The distribution half-times of the drug were 1.52 h in the normal and 0.81 h in the febrile dogs. The drug distribution was significantly more rapid ( P < 0.05) in febrile than in normal dogs. Average ± SD values for the half-lives of the drug were 16.2 ± 5.7 h in normal and 16.7 ± 4.7 h in the febrile dogs. The apparent volume of distribution ( V ' _d (area)) was 628 ± 251 ml/kg in the normal dogs, and was not statistically different from 495 ± 144 ml/kg in the febrile dogs. The volume of the central compartment ( V ' _c ) was 445 ± 55 ml/kg in normal dogs and this was significantly higher ( P < 0.01) than the V ' _c of 246 ± 72 ml/kg in the febrile dogs. The body clearance was 22.4 ± 4.8 and 20.2 ± 3.6 ml/hour. kg in the normal and febrile dogs, respectively. The investigation revealed that the dosage regimen of sulphadimidine did not differ significantly between normal and febrile dogs.     

High-Frequency Jet Ventilation in Anesthetized, Paralyzed Dogs and Cats Via Transtracheal and and Endotracheal Tube Routes

The ability of the SAV 6 high-frequency jet ventilator to effectively ventilate three anesthetized, paralyzed cats (3.2–4.2 kg), two small dogs (7.2 and 10.0 kg), six medium-sized dogs (20.5–25.0 kg), and three large dogs (36.0–43.0 kg) via a 14-gauge (dogs) or a 16-gauge (cats) catheter placed percutaneously into the trachea via the cricothyroid membrane or into a preplaced endotracheal tube was evaluated. The lowest driving pressure within the range of 0.25 to 2.0 kg/cm² (1 kg/cm²= 14.2 psi) and the highest cycle rate within the range of 60 to 240 per minute that would generate a PaCO₂ of 30 ± 3 mm Hg were determined.
All animals could be ventilated to a PaC0₂ of 30 ± 3 mm Hg by the endotracheal tube and transtracheal route, except the largest dogs, which couid be ventilated to an average PaC0₂ of 36 mm Hg by the transtracheal route. The transtracheal route consistently required higher driving pressures and lower cycle rates than did the endotracheal tube route. Cats could be ventilated with a driving pressure of 0.25 kg/cm²; small dogs could be ventilated with 0.5 to 1.0 kg/cm₂; medium-sized dogs with 1.0 to 1.5 kg/cm²; and large dogs with 1.5 to 2.0 kg/cm².
The SAV 6 high-frequency jet ventilator can effectively ventilate cats and dogs (7.2–43.0 kg) via a transtracheal catheter and an endotracheal tube.     

Ionized Hypocalcemia in Critically Ill Dogs

Background: Ionized hypocalcemia (iHCa) is a common electrolyte disturbance in critically ill people, especially those with sepsis. The cause of the iHCa is not entirely understood and is likely multifactorial. Critically ill people with iHCa have longer hospital stays and higher mortality rates compared to people with normocalcemia. There are no published clinical studies evaluating the incidence and impact of iHCa in critically ill dogs.
Hypothesis: iHCa occurs in critically ill dogs, is more prevalent in dogs with systemic inflammatory response syndrome (SIRS) or sepsis, and is associated with longer hospital stays and higher mortality.
Animals: One hundred and forty-one client-owned dogs admitted to a companion animal intensive care unit (ICU) in a veterinary teaching hospital.
Methods: Prospective observational study of sequentially enrolled dogs. Blood was collected and analyzed within an hour of admission from all dogs presented to the ICU that met study inclusion criteria.
Results: The incidence of iHCa (iCa < 1.11 mmol/L) was 16%. The presence of iHCa was associated with longer ICU ( P = .038) and hospital ( P = .012) stays but not with decreased survival ( P = .60). Dogs with sepsis as defined by ≥3 SIRS criteria and a positive culture were more likely to have iHCa ( P = .050).
Conclusions and Clinical Relevance: In dogs not previously treated with fluids or blood products intravenously, the finding of iHCa upon admission to the ICU predicted a longer duration of ICU and hospital stay. Septic dogs with positive cultures were more likely to have iHCa.     

PULMONARY VENOUS FLOW CHARACTERISTICS AS ASSESSED BY TRANSTHORACIC PULSED DOPPLER ECHOCARDIOGRAPHY IN NORMAL DOGS

Transthoracic Doppler echocardiography was used to evaluate the technique of measuring and normal patterns of pulmonary venous flow in fourteen normal dogs. Polyphasic pulmonary venous flow profiles were obtained in all dogs, consisting of one (S) or two (S_E and S_L) systolic forward flow waves, one early diastolic forward flow wave (D), one reverse flow wave (R) related to atrial contraction, and one reverse flow wave (R₂) observed after cessation of systolic flow. Pulmonary venous flow was laminar in 9 dogs (65%). Maximal flow velocity during systole (0.39 ± 0.14 m/sec) was significantly lower (P < 0.01) than in early diastole (0.56 ± 0.14 m/sec). During late diastole peak flow velocity was 0.20 ± 0.08 m/sec and maximum R₂ velocity was 0.17 ± 0.05 m/sec. Duration of mitral A-wave was significantly greater (P < 0.05) than R-wave duration in all dogs (0.075 ± 0.10 vs 0.058 ± 0.012 sec). These results can be used for comparison with patterns found in disease states.     

Cardiopulmonary Effects of Using Carbon Dioxide for Laparoscopic Surgery in Dogs

Cardiopulmonary effects of laparoscopic surgery were investigated in five crossbred dogs (21 ± 1.9 kg). Premedicated dogs were anesthetized with thiopental and maintained with halothane at 1.5 times minimum alveolar concentration in oxygen. Controlled ventilation maintained partial pressure of end-tidal co₂ at 40 ± 2 mm Hg. Vecuronium was used for skeletal muscle relaxation. After instrumentation and stabilization, baseline measurements were made of cardiac output (thermodilution technique), mean systemic, mean pulmonary arterial and pulmonary wedge pressures, heart rate, saphenous vein and central venous pressures, and minute ventilation. Baseline arterial and mixed venous blood samples were drawn for analysis of pH, Pao₂, Paco₂, Pvo₂, Pvco₂, and bicarbonate concentrations. Systemic and pulmonary vascular resistances, oxygen delivery and consumption, shunt fraction, and dead space ventilation were calculated using standard formulas. Abdominal insufflation using co₂ to a pressure of 15 mm Hg for 180 minutes resulted in significant ( P <.05) increases in heart rate (15 to 180 minutes), minute ventilation (75 to 135 minutes), and saphenous vein pressure (15 to 180 minutes), and decreases in pH (60 to 180 minutes) and Pao₂ (60 to 180 minutes). For 30 minutes after desufflation, there was a significant decrease in Pao₂, and increases in cardiac output, o₂ delivery, and heart rate, compared with baseline. There was a significant increase in shunt fraction and decrease in pH at 15 minutes after desufflation only. The changes were within physiologically acceptable limits in these healthy, ventilated dogs.