Echocardiographic and electrocardiographic findings in Irish Wolfhounds eating high-pulse or low-pulse diets.

BACKGROUND: Apparently healthy dogs of various breeds eating nontraditional, high-pulse diets can have larger left ventricular diameter, lower systolic function, and more ventricular premature complexes (VPCs) compared with dogs eating traditional, low-pulse diets. It is unknown whether Irish Wolfhounds eating high-pulse diets have similar cardiac abnormalities. HYPOTHESIS/OBJECTIVES: To compare electrocardiographic and echocardiographic findings between Irish Wolfhounds eating high- or low-pulse diets. ANIMALS: Ninety-seven Irish Wolfhounds. METHODS: Retrospective study of Irish Wolfhounds that had echocardiography performed at dog shows between October 2018 and May 2021. Demographic information, echocardiographic measurements, cardiac rhythm (1-minute lead II rhythm strip), and main diet were recorded retrospectively. Diets were classified as high-pulse or low-pulse based on the presence and location of pulses (peas, lentils, chickpeas, or dry beans) on the ingredient list. RESULTS: Thirty-five of 97 Irish Wolfhounds (36%) were eating high-pulse diets and 62 of 97 (64%) were eating low-pulse diets. There were no significant differences between diet groups in echocardiographic measurements. A significantly higher percentage of dogs in the high-pulse diet group (6/35 [17%]) had VPCs compared with those in the low-pulse diet group (1/62 [2%]; effect size = 0.15 [95% confidence interval: 0.004-0.31]; P = .005). CONCLUSIONS AND CLINICAL IMPORTANCE: In this retrospective study of apparently healthy Irish Wolfhounds, high-pulse diets were associated with a higher prevalence of VPCs which could represent early cardiac abnormalities.

Heritability and genetic variance estimation of Osteosarcoma (OSA) in Irish Wolfhound, using deep pedigree information.

BACKGROUND: Osteosarcoma (OSA) is a devastating disease that is common in the Irish Wolfhound breed. The aim of this study was to use a pedigree-based approach to determine the heritability of OSA in the Irish Wolfhound using data from a large publically available database. RESULTS: The pedigree used for this study included 5110 pure-bred Irish Wolfhounds, including 332 dogs diagnosed with OSA and 360 control dogs; dogs were considered controls if they lived over 10 years of age and were not reported to have developed OSA. The estimated heritability of OSA in the Irish Wolfhound was 0.65. CONCLUSION: The results of this study indicate that OSA in the Irish Wolfhound is highly heritable, and support the need for future research investigating associated genetic mutations.

Osteosarcoma is a devastating condition that is prevalent in the Irish Wolfhound breed. In this study, our aim was to estimate heritability of osteosarcoma in the Irish Wolfhound breed. We undertook a pedigree-based analysis to estimate heritability of osteosarcoma in the Irish Wolfhound. The pedigree used included 5110 pure-bred Irish Wolfhounds, including 332 dogs diagnosed with osteosarcoma and 360 control dogs. We considered dogs to be controls if they were over 10 years of age and were not reported to have developed osteosarcoma. This study found the heritability estimate of osteosarcoma in the Irish Wolfhound to be 0.65. This score means that osteosarcoma in this breed is: 1) highly heritable and 2) a complex trait, which means that both environmental and genetic factors influence disease risk. Overall, our results provide support for further investigation into the genetic variants involved in the development of osteosarcoma in Irish Wolfhounds.

Echocardiographic and electrocardiographic evaluation of North American Irish Wolfhounds.

BACKGROUND: Cardiac disease is an important cause of morbidity and mortality in Irish Wolfhounds (IWs), but its prevalence and clinical characteristics in North American IWs are incompletely described. HYPOTHESIS/OBJECTIVES: That atrial fibrillation (AF) is a diagnostic marker of echocardiographic abnormalities, and that clinical characteristics predict development of IW cardiomyopathy (IWCM). To define the prevalence of arrhythmias and echocardiographic abnormalities in North American IWs. ANIMALS: Six hundred and forty-five adult IWs presented for screening examinations intended to identify familial cardiac disease. METHODS: In this retrospective cohort study, reference intervals defined based on echocardiographic data from IW classified as normal, were used to define the prevalence of structural and functional abnormalities. A logistic model was developed to identify clinical findings that predict future development of IWCM. RESULTS: The prevalence of AF was 8.9% (95% confidence interval [CI], 6.6-11.2) of which 55.5% had echocardiographic abnormalities. IWCM defined by left atrial enlargement, left ventricular dilatation, and systolic dysfunction had a prevalence of 1.8% (0.72-2.8). Positive and negative likelihood ratios for AF in the identification of IWCM were, respectively, 10.8 (7.29-16) and 0.2 (0.06-0.69). Multivariable logistic regression identified AF (odds ratio [OR]; 10.6, 95% CI, 2.67-42.3) and male sex (OR; 3.8, 95% CI, 1.02-14) as predictors of future development of IWCM. CONCLUSIONS AND CLINICAL IMPORTANCE: Atrial fibrillation is common in North American IW. It occurs in association with structural cardiac disease but also in its absence. Irish Wolfhounds cardiomyopathy is characterized by chamber enlargement but minimally decreased ejection phase indices of myocardial function. Atrial fibrillation is a risk factor for future development of IWCM.

Pedigree analysis of atrial fibrillation in Irish wolfhounds supports a high heritability with a dominant mode of inheritance.

BACKGROUND: Atrial fibrillation (AF) is the most common arrhythmia in dogs. The Irish Wolfhound breed has a high prevalence of AF making them an ideal breed to investigate possible genetic contributions to this disease. The aim of this study was to perform a heritability analysis in North American Irish Wolfhounds using phenotype data from cardiac screenings performed between 2000 and 2019 in order to determine how much of this disease can be attributed to genetics compared to environmental causes. The second aim was to determine the disease mode of inheritance to help inform prevention and breeding practices. RESULTS: There were 327 Irish Wolfhounds diagnosed with AF and 136 Irish Wolfhounds over 8 years of age without AF. The estimated mean (95% confidence interval) heritability of AF in Irish Wolfhounds was 0.69 (0.50-0.86). The pedigree was consistent with a dominant mode of inheritance. CONCLUSION: Results of this study indicate a strong genetic contribution to AF in Irish Wolfhounds and suggest that future research to identify causative genetic mutations is warranted.

Indirect arterial blood pressure measurement in nonsedated Irish wolfhounds: reference values for the breed.

Arterial blood pressure measurements were obtained from 158 healthy Irish wolfhounds using the oscillometric technique to establish reference values for the breed. In contrast to other sight hounds, Irish wolfhounds have low arterial blood pressure. Mean systolic pressure for the group was 116.0 mm Hg. Mean diastolic pressure was 69.2 mm Hg, and the mean value for mean arterial pressure was 87.8 mm Hg. Blood pressure measurements were higher in older wolfhounds than in young dogs. There was no difference between systolic and mean arterial blood pressures in lateral recumbency compared to standing position. However, diastolic pressure was slightly lower when standing. Calm dogs had lower pressure than anxious wolfhounds. There was a significant interaction between the effects of age, gender, and mood on systolic, diastolic, and mean arterial blood pressure values.