Association of single‐nucleotide polymorphism of melanocortin gene with feed intake in rabbit (Oryctolagus cuniculus)

The aim of the study was to investigate the association of two parts of melanocortin gene (MC4R‐1, MC4R‐2) and feed intake for V‐line rabbits. V‐line rabbits were grouped into high and low daily feed intake during the period from 30 to 63 days of age in order to identify MC4R SNPs useful for association study with feed intake. DNA from blood samples of each group was extracted to amplify the MC4R gene. The purified PCR products were sequenced in those had the highest and lowest feed intake. Alignment of sequence data from each group revealed that there is a variation detected in MC4R‐1 at nucleotide 35 (T‐G) (sense mutation) and another variation was detected in MC4R‐2 gene at nucleotide 19 (T‐C) (sense mutation) for high feed intake rabbits. These sense mutations lead to transform some amino acids and cause a significant change of the MC4R function. The results of average daily feed intake (ADFI) indicated that group (1) had significantly higher feed intake than group (2) of V‐line rabbits. The detected mutations and the analysis of daily feed intake means revealed a significant association between MC4R polymorphism and feed intake in rabbits.     

Ability of a 5‐Minute Electrocardiography (ECG) for Predicting Arrhythmias in Doberman Pinschers with Cardiomyopathy in Comparison with a 24‐Hour Ambulatory ECG

Background: Ventricular premature contractions (VPCs) are common in the occult stage of cardiomyopathy in Doberman Pinschers. Although the gold standard for detecting arrhythmia is the 24‐hour ambulatory electrocardiography (ECG) (Holter), this method is more expensive, time‐consuming and often not as readily available as common ECG. Objectives: Comparison of 5‐minute ECGs with Holter examinations. Animals: Eight hundred and seventy‐five 5‐minute ECGs and Holter examinations of 431 Doberman Pinschers. Methods: Each examination included a 5‐minute ECG and Holter examination. A cut‐off value of >100 VPCs/24 hours using Holter was considered diagnostic for the presence of cardiomyopathy. Statistical evaluation included calculation of sensitivity, specificity, positive predictive value, and negative predictive value. Results: Holter examinations revealed >100 VPCs/24 hours in 204/875 examinations. At least 1 VPC during a 5‐minute ECG was detected in 131 (64.2%) of these 204 examinations. No VPCs were found in the 5‐minute ECG in 73 (35.8%) examinations of affected Doberman Pinschers. A 5‐minute ECG with at least 1 VPC as cut‐off had a sensitivity of 64.2%, a specificity of 96.7%, a positive predictive value of 85.6% and a negative predictive value of 89.9% for the presence of >100 VPCs/24 hours. Conclusions and Clinical Importance: A 5‐minute ECG is a rather insensitive method for detecting arrhythmias in Doberman Pinschers. However, the occurrence of at least 1 VPC in 5 minutes strongly warrants further examination of the dog, because specificity (96.7%) and positive predictive value (85.6%) are high and could suggest occult cardiomyopathy.     

Antibodies against Crandell Rees Feline Kidney (CRFK) Cell Line Antigens, α‐Enolase,and Annexin A2 in Vaccinated and CRFK Hyperinoculated Cats

Background: Cats inoculated with feline herpesvirus 1, calicivirus, and panleukopenia (FVRCP) vaccines grown on the Crandell Rees feline kidney (CRFK) cell line have been shown to develop anti‐CRFK antibodies. The identities of common CRFK antigens are unknown. Hypothesis: Cats inoculated with CRFK lysates and FVRCP vaccines will develop autoantibodies measurable by Western blot immunoassay. Antigens associated with these antibodies can be isolated for further study. Animals: One CRFK hyperinoculated rabbit, 44 age‐matched unvaccinated kittens purchased from a commercial vendor. Methods: Commonly recognized CRFK antigens were identified by comparison of Western blot immunoassays using sera from a hyperinoculated rabbit and kittens inoculated with CRFK lysate or 1 of 4 commercially available FVRCP vaccines. Antigens were purified from CRFK lysates and sequenced. Antigen recognition was confirmed by Western blot immunoassay and indirect ELISA for 2 proteins using sera from CRFK and FVRCP inoculated kittens. Results: CRFK antigens 47, 40, and 38 kD in size were identified. Protein isolation and sequencing identified 3 CRFK proteins as α‐enolase, annexin A2, and macrophage capping protein (MCP). Sera from FVRCP and CRFK inoculated cats were confirmed to recognize annexin A2 and α‐enolase by Western blot immunoassay and indirect ELISA. Conclusions and Clinical Relevance: This study validated the use of Western blot immunoassay for detection of antibodies against CRFK proteins and identified 3 CRFK antigens. In humans, α‐enolase antibodies are nephritogenic; α‐enolase and annexin A2 antibodies have been associated with autoimmune diseases. Further research will be necessary to determine the clinical relevance of these findings.