Hematobiochemical findings of DCM in Labrador Retrievers

Introduction

The DCM is a progressive myocardial disease in Labrador Retrievers characterized by ventricular dilation, impaired systolic function and reduced myocardial contractility leading to CHF and increased risk of cardiac death (Freeman et al., 2022) [4] . The most frequently reported signs of DCM in Labrador Retrievers include exercise intolerance, difficulty in breathing, rapid respiration and cough associated with left-sided heart failure, whereas rightsided heart failure in Labrador Retrievers may present with abdominal distension, jugular vein distension and pulsation along with additional signs such as cold extremities, weight loss, syncope, low intensity systolic murmur, weak femoral pulse and cyanosis. Thorough patient history, results of physical examination, electrocardiography and thoracic radiography provided a practical means of diagnosing DCM in Labrador Retrievers.

Materials and Methods

Haematology

Blood sample was collected from the cephalic or saphenous vein using disposable syringes and transferred into EDTA vials for whole blood analysis. Haemoglobin was measured as per Sahli's acid hematin method using a Sahli's haemoglobinometer and the readings were recorded in g/dL (Benjamin, 2007) [1] . Packed cell volume was determined using the microhematocrit technique following standard procedures and the results were expressed as a percentage (Benjamin, 2007) [1] . Erythrocyte counts were obtained following the procedure described by Weiss and Tvedten (2004) [19] and expressed as millions/µL.White blood cells were enumerated using a dilution method based on Benjamin (2007) [1] , with values reported as thousands/µL. Blood smears were stained with Field's stain (Jain, 1986) [5] and the differential leukocyte count was conducted using the battlement technique. A total of 100 leukocytes were assessed and the percentages of individual cell types were documented according to Benjamin (2007) [1] .

Serum Biochemistry

Blood sample was collected in clot-activator tubes for serum separation. After separation, serum was transferred and stored at -20 0 C until biochemical analysis was performed. The estimation of blood urea nitrogen (BUN), Serum Creatinine, Alanine transferase, Aspartate transferase, Total protein and albumin was performed in semiautomatic analyser using ERBA diagnostic kits, following the instructions provided by the manufacturer.

Results

Hematology

The mean values of hematological parameters of control Labrador Retrievers and DCM Labrador Retrievers were presented in Table-I. The mean values of hemoglobin (Hb), packed cell volume (PCV), total erythrocyte count (TEC), total leukocyte count (TLC)of control group were 12.73 + 0.36 g%, 37.50+1.99%, 6.20+0.50 millions/mm 3 The mean value of hemoglobin was significantly decreased (P<0.01) in DCM Labrador Retrievers (11.16+0.38g%) when compared to healthy control (12.73 + 0.36g%). The mean value of packed cell volume (PCV) also significantly decreased (P<0.01) in DCM Labrador Retrievers (32.33+1.99%) when compared to healthy Labrador Retrievers (37.50+0.55%). In the similar manner, there was a significant decrease (P<0.01) in the mean total erythrocyte count of DCM Labrador Retrievers (4.54+0.22 millions/mm 3 ) when compared to apparently healthy Labrador Retrievers (6.20+0.50 millions/mm 3 ). There was a significant increase (P<0.01) in the mean total leukocyte count (17.14+0.46 thousand/mm 3 ) of DCM Labrador Retrievers when compared to apparently healthy control (9.70 +0.82 thousand/mm 3 ). The mean value of neutrophils was significantly increased (P<0.01) (76.00+1.50%) in DCM Labrador Retrievers when compared to apparently healthy control (66.37 + 2.31%). The mean value of lymphocytes was significantly decreased (P<0.01) in DCM Labrador Retrievers (21.16+0.19%) when compared to apparently healthy control (30.87 + 1.34%). In the present study, there was no significant difference (P>0.05) in the mean values of monocytes and eosinophils of Labrador Retrievers with DCM when compared to the control group.

Discussion

Hematology

The mean+SE values of hematological parameters (Hb, PCV, TEC, TLC and DLC) in apparently healthy Labrador Retrievers were with in normal range, as reported by Wess and Tvedten, (2004), Benjamin, (2007) [1] and Sree Sai Jyosthna et al. (2024) [15] . In the present study, the mean values of haemoglobin, packed cell volume and total erythrocyte counts were significantly decreased when compared to control group. The present findings were in agreement with previous authors (Vishnurahav et [18,10,15] . While the mean values of total leukocyte count and neutrophils were significantly increased when compared to control group. The present findings were in accordance with earlier observations (Mayani et [10,12,3,20] . However, no significant difference was noticed in the mean values of monocytes and esionophils between control and DCM Labrador Retrievers, which was in accordance with the findings of (Jeyaraja et al., 2015; Vishnurahav et al., 2018 and Sree Sai Jyothsna et al., 2024) [6,18,15] . The reason for the low haematocrit could be associated with the fluid retention that occurs in congestive heart failure and thus haemodilution (Martin et al., 2010; Mayani et al., 2022 and Sai krishna et al., 2022) [9, 10, ] . In the present study, presence of concurrent bacterial infection in the DCM Labrador Retrievers might be responsible for leukocytosis and neutrophilia (Mayani et [10,3,20] .

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