Canine Breeds Research Articles

3D Digital and Printed Hearts from Different Canine Breeds as an Educational Tool for Radiographic Interpretation.

Three-dimensional (3D) printing is a new method of creating anatomical models, which can enhance the training of students and health professionals. The large breed-variation in dogs means that interpretation of thoracic radiographs can be challenging for the inexperienced radiologist. The aim of this study was to develop digital and printed 3D cardiac models from six canine breeds and evaluate their use as a tool for studying breed variations in radiology. The printed and digital 3D cardiac models were used by postgraduate veterinary students in diagnostic imaging along with a theoretical class on the subject and students completed a pre- and post-test, assessing cardiac size on thoracic radiographs in order to verify the usefulness of the models. The students then completed a satisfaction questionnaire using a Likert scale. There was a significant difference between the pre-test and the post-test results, with greater accuracy after using the 3D models. More errors were made in pre-test interpretation of radiographs from English Cocker Spaniel, English Bulldog, and Yorkshire Terrier and there were a significantly higher number of correct answers after using the 3D models. The vast majority of responses to all questions in the satisfaction questionnaire were positive, with partial or total agreement of the participants. This study demonstrates that digitally printed cardiac models from different breeds of dogs are effective learning tools. They helped students to better understand the relevant spatial relationship and cardiac morphology and to compare this anatomy with the radiographic image. Models are provided in 3D PDF and STL files for download.

Alternative Lengthening of Telomeres Is Rare in Canine Histiocytic Sarcoma.

Cancer cells activate telomere maintenance mechanisms (TMMs) to overcome senescence and thus are targets for TMM-specific therapies. Telomerase-independent alternative lengthening of telomeres (ALT) is frequently utilized as a TMM in human sarcoma subtypes. Histiocytic sarcoma (HS) is a rare but aggressive tumor of hematopoietic origin with unknown ALT incidence in humans. ALT has been identified in canine HS, a tumor type comparable to human HS that occurs with high rates in certain canine breeds such as Bernese mountain dogs (BMDs). This retrospective study characterized the frequency of ALT in BMD and non-BMD patients diagnosed with HS as surrogates for humans. Formalin-fixed paraffin-embedded tumor samples from 63 dogs at two centers, including 47 BMDs, were evaluated for their ALT activity and relative telomere content (TC) using a radiolabel C-circle assay (CCA). Known ALT-positive samples served as controls. CCA-positive cases were validated via FISH. Two BMD samples showed ALT activity of 1-14% compared to controls. All other samples were ALT-negative. The TC did not correlate with the CCA results. ALT positivity was validated by the appearance of ultrabright telomere foci. Low ALT activity was present in 4% of BMDs with HS and therefore does not appear to be a common target for therapeutic approaches but can have diagnostic value.

Clinical retrospective study of vaginal hyperplasia in the bitch (2012-2022).

A retrospective study was used to analyse canine vaginal hyperplasia ambulatory cases in Small animal clinic of the University Veterinary Hospital of the Faculty of Veterinary Medicine, Trakia University in Stara Zagora, Bulgaria between 2012 and 2022. The study was done to investigate the morbidity of vaginal hyperplasia in the bitch and its relationship with the breed, body weight, age, stage of the oestrous cycle, parity of dogs and grade of the condition. Grade II and grade III vaginal hyperplasia were observed in 3.11% of all female dog genital pathological cases. Twenty-eight canine breeds were affected and the largest number were Central Asian Shepherds (30.47%). Most frequently the dogs were between 2 and 3 years old (29.68%), above 40 kg body weight (58.59%) and during follicular phase (proestrus and oestrus) of the oestrous cycle (82.02%). All the affected bitches were non-spayed (100%) and nulliparous were 70.31% of them. Grade III vaginal hyperplasia was more frequently observed (53.13%) than grade II of the condition. High correlation was found between age of the bitches and grade of the vaginal hyperplasia (R2 = .551; SEE = 0.053), body weight and grade of the condition (R2 = .820; SEE = 0.054), and age of the animals and their body weight (R2 = .820; SEE = 1.27).

Treatment of Canine Disc-Associated Cervical Spondylomyelopathy with a Cervical Distraction-Stabilization Technique (C-LOX Combined with LCP Plate) and Clinical Outcomes.

Canine disc-associated cervical spondylomyelopathy (DA-CSM) is a form of caudal CSM, characterized by the compression of the spinal cord and nerve roots due to an intervertebral disc protrusion. It is more frequent in large canine breeds. A variety of surgical techniques has been proposed for DA-CSM. The aim of the study was to evaluate the outcomes of a cervical distraction-stabilization technique using an intervertebral anchored fusion device (C-LOX) combined with a locking compression plate (LCP plate) for the treatment of DA-CSM in dogs, based on clinical and radiographical follow-up data. Thirteen dogs affected by DA-CSM were included in the study. After the surgical procedure, an improvement in neurological status was documented in 9/13 cases. This cervical distraction-stabilization technique seems to be a valuable surgical alternative to treat this canine pathology.

Comparison of CT-measured angles of pelvic limbs without patellar luxation of six canine breeds.

Dogs with medial patellar luxation can be affected by pelvic limb deformities whose corrective osteotomies and associated biomechanical rebalancing might provide higher success rates than standard surgical procedures limited to the stifle joint. In bilaterally affected canine patients, comparison with the contralateral normal limb is impossible. Reference values are useful for orthopedic decision-making. Inconsistency of published reference values might depend on methodology or canine breed. We hypothesized that canine pelvic limb alignment is breed-specific. CT scans of 42 pelvic limbs of dog breeds predisposed for medial patellar luxation, with an orthotopic patellar position and stability were studied. Several angleswere measured with an open-source 3D Slicer plugin using vector calculations. The breeds were compared with a general linear model with a Bonferonni adjustment using SPSS. Chihuahuas, Pomeranians, Jack Russel Terriers, Pugs, French Bulldogs, Maltese were examined. In the order of the listed breeds, the angles were as follows: 28.3°±10.7°, 20.1°±2.9°, 35.4°±6.9°, 32.8°±3.0°, 19.0°±7.1°, 26.6°±5.3° for the antetorsion, 5.3°±1.8°, 2.8°±2.8°, 8°±4.4°, 3.8 °±3.1°, 4.7°±3.3°, 2.3°±3.3° for the femoral varus, of -5.5°±6.2°, 1.1°±4.1°, -5.2°±9.5°, 6.1°±8.0°, -0.1°±5.9°, -9.2°±4.7° for the tibial torsion, 2.0°±2.9°, 2.1°±2.7°, 6.4°±6.8°, 0.0°±5.7°, 3.0°±5.8°, 8.8°±8.6° for the tibial valgus, 1.2°±10.4°, 1.8°±3.4°, -1.7°±4.9°, -1.7°±9.4°, 5.1°±8.8°, -0.2°±8.6° for the femorotibial rotation and -3.4°±2.2°, 1.1°±4.1°, -2.8°±3.4°, -5.2°±4.0°, -2.1°±4.4°, -5.4°±3.7° for the tibiotalar rotation. There were significant differences between breeds in femoral torsion, femoral varus, and tibial torsion angles, but no significant differences in tibial valgus, femorotibial, and tibiotalar rotation angles. Our hypothesis is therefore partially correct. Our results are limited to small dogs prone to medial patellar luxation and might not be generalized. To establish robust reference values larger case numbers and more breeds should be evaluated. In conclusion, canine pelvic limb alignment reference values for small dogs with a predisposition for medial patellar luxation should be considered breed-specific.

Immunological profile of two canine breeds in an endemic region of Leishmania infantum.

Visceral leishmaniosis is the one of the most important protozoal zoonoses in Europe, and it is caused by Leishmania infantum, an intracellular protozoan parasite. The disease is endemic in dogs in the Mediterranean area. The main goal of this work is to correlate the levels of several cytokines linked to immune response against L. infantum infection in two canine breeds. Thirty-one Boxer and twenty-eight Ibizan Hound dogs living in the Valencian Community (East coast of Spain) were analyzed for the presence of anti-Leishmania antibodies in serum by IFAT test. Cytokines IFN-γ, TNF-α, IL-2, IL-6, IL-8, and IL-18 were determined by ELISA commercial tests. The levels of IFN-γ, IL-2, and IL-18 in our study, cytokines linked to a cellular immune response, were higher (p<0.05) in the Ibizan Hound breed; IL-6 levels were higher, although not significant, and only levels of IL-8 were higher in Boxer than in Ibizan Hound. No expression of TNF-α was found. These results corroborate that Ibizan Hound can develop a protective response against canine leishmaniosis, while Boxer is a susceptible breed. The study of immunological aspects in the different canine breeds may represent a useful tool in the prediction of the disease.

Electrocardiographic findings in healthy Cavalier King Charles Spaniels, Pugs, and English Bulldogs.

To describe the ECG findings in 3 different canine brachycephalic breeds: the Cavalier King Charles Spaniel, the Pug, and the English Bulldog (EB). 135 healthy dogs (50 Cavalier King Charles Spaniels, 50 Pugs, and 35 EBs). Medical records were retrospectively reviewed to identify healthy dogs ≥ 1 year old that had undergone an ECG. The Mann-Whitney U test or the Student t test were used to compare continuous variables between male and female dogs, whereas the χ2 test was used for categorical variables. Spearman correlation coefficients between ECG measurements and age and body weight were also calculated in the case of continuous variables, whereas the Kruskal-Wallis test was used for categorical ones. Electrocardiographic parameters of healthy Cavalier King Charles Spaniels overall fitted with traditional reference intervals cited in textbooks; in contrast, 28% of Pugs and 20% of EBs showed a shift of the QRS-complex mean electrical axis (QRS-MEA). In Pugs and EBs, the mean/median QRS-MEA value was 56° (from 0° to 100°) and 59° (from 20° to 100°), respectively. All axis shifts were left shifts (in Pugs, from 0° to 34°; in EBs, 20° to 39°). Only a few meaningful differences were found when comparing ECG variables between males and females. Similarly, only 1 statistically significant correlation was found between ECG parameters and age and body weight. Healthy Pugs and EBs present a trend to a left shift of the QRS-MEA. This should be considered when interpreting ECG tracings in these breeds.

Genetic haplotypes associated with immune response to Leishmania infantum infection in dogs.

Leishmaniasis is a zoonotic parasitic disease, and the main reservoir of the parasite is the dog, although recent years have seen an increase in other mammalian species. In the Mediterranean region, where it is an endemic disease, it is caused by the species Leishmania infantum. The Ibizan hound, an autochthonous breed of this region, appears to have a genetic resistance to parasitic infection, whereas other canine breeds, such as the Boxer, are susceptible to infection. These differences are related to the differentiated activation of the immune response, with the Ibizan hound activating the Th1 immune response, whereas the Boxer breed triggers the Th2 immune response. Cytokine levels and genomic haplotypes of several genes involved in the immune response were analysed in twenty-eight Ibizan hound (resistant canine breed model) and twenty-four Boxer (susceptible canine breed) without clinical signs in the Mediterranean region. Cytokine levels were analysed by ELISA commercial kits and haplotypes were studied using CanineHD DNA Analysis BeadChip including 165,480 mapped positions. The results show 126 haplotypes associated with differential immune response in dogs. Specifically, haplotypes in IL12RB1, IL6R, CIITA, THEMIS, NOXA1, HEY2, RAB38, SLC35D2, SLC28A3, RASEF and DAPK1 genes are associated with serum levels of IFN-γ, IL-2, IL-8, and IL-18. These results suggest that the resistance or susceptibility to Leishmania infantum infection could be a consequence of haplotypes in several genes related to immune response. Future studies are needed to elucidate the relationship of these haplotypes with immune response and gene expression regulation.

Diagnosis, Prognosis, and Treatment of Canine Hemangiosarcoma: A Review Based on a Consensus Organized by the Brazilian Association of Veterinary Oncology, ABROVET

Hemangiosarcoma is a mesenchymal neoplasm originating in the endothelial cells of blood vessels; they can be classified as non-visceral and visceral types. Non-visceral hemangiosarcomas can affect the skin, subcutaneous tissues, and muscle tissues; visceral hemangiosarcomas can affect the spleen, liver, heart, lungs, kidneys, oral cavity, bones, bladder, uterus, tongue, and retroperitoneum. Among domestic species, dogs are most affected by cutaneous HSA. Cutaneous HSA represents approximately 14% of all HSA diagnosed in this species and less than 5% of dermal tumors, according to North American studies. However, Brazilian epidemiological data demonstrate a higher prevalence, which may represent 27 to 80% of all canine HSAs and 13.9% of all skin neoplasms diagnosed in this species. Cutaneous HSA most commonly affects middle-aged to elderly dogs (between 8 and 15 years old), with no gender predisposition for either the actinic or non-actinic forms. The higher prevalence of cutaneous HSA in some canine breeds is related to lower protection from solar radiation, as low skin pigmentation and hair coverage lead to greater sun exposure. Actinic changes, such as solar dermatosis, are frequent in these patients, confirming the influence of solar radiation on the development of this neoplasm. There are multiple clinical manifestations of hemangiosarcoma in canines. The diagnostic approach and staging classification of cutaneous HSAs are similar between the different subtypes. The definitive diagnosis is obtained through histopathological analysis of incisional or excisional biopsies. Cytology can be used as a presurgical screening test; however, it has little diagnostic utility in cases of HSA because there is a high risk of blood contamination and sample hemodilution. Surgery is generally the treatment of choice for dogs with localized non-visceral HSA without evidence of metastatic disease. Recently, electrochemotherapy (ECT) has emerged as an alternative therapy for the local ablative treatment of different neoplastic types; the use of radiotherapy for the treatment of dogs with cutaneous HSA is uncommon. There is greater consensus in the literature regarding the indications for adjuvant chemotherapy in subcutaneous and muscular HSA; doxorubicin is the most frequently used antineoplastic agent for subcutaneous and muscular subtypes and can be administered alone or in combination with other drugs. Other therapies include antiangiogenic therapy, photodynamic therapy, the association of chemotherapy with the metronomic dose, targeted therapies, and natural products. The benefits of these therapies are presented and discussed. In general, the prognosis of splenic and cardiac HSA is unfavorable. As a challenging neoplasm, studies of new protocols and treatment modalities are necessary to control this aggressive disease.

Interleukin 6 and interferon gamma haplotypes are related to cytokine serum levels in dogs in an endemic Leishmania infantum region

BackgroundThe Ibizan Hound is a canine breed native to the Mediterranean region, where leishmaniasis is an endemic zoonosis. Several studies indicate a low prevalence of this disease in Ibizan Hound dogs, whereas other canine breeds present a high prevalence. However, the underlying molecular mechanisms still remain unknown. The aim of this work is to analyse the relationship between serum levels of cytokines and the genomic profiles in two canine breeds, Ibizan Hound (resistant canine breed model) and Boxer (susceptible canine breed model).MethodsIn this study, we analyse the haplotypes of genes encoding cytokines related to immune response of Leishmania infantum infection in twenty-four Boxers and twenty-eight Ibizan Hounds apparently healthy using CanineHD DNA Analysis BeadChip including 165,480 mapped positions. The haplo.glm extension of haplo.score was used to perform a General Linear Model (GLM) regression to estimate the magnitude of individual haplotype effects within each cytokine.ResultsMean levels of interferon gamma (IFN-γ), interleukin 2 (IL-2) and IL-18 in Boxer dogs were 0.19 ± 0.05 ng/ml, 46.70 ± 4.54 ng/ml, and 36.37 ± 30.59 pg/ml, whereas Ibizan Hound dogs present 0.49 ± 0.05 ng/ml, 64.55 ± 4.54 ng/ml, and 492.10 ± 31.18 pg/ml, respectively. The GLM regression shows fifteen haplotypes with statistically significant effect on the cytokine serum levels (P < 0.05). The more relevant are IL6-CGAAG and IFNG-GCA haplotypes, which increase and decrease the IL-2, IL-8 and IFN-γ serum levels, respectively.ConclusionsHaplotypes in the IFNG and IL6 genes have been correlated to serum levels of IFN-γ, IL-2 and IL-18, and a moderate effect has been found on IL8 haplotype correlated to IL-8 and IL-18 serum levels. The results indicate that the resistance to L. infantum infection could be a consequence of certain haplotypes with a high frequency in the Ibizan Hound dog breed, while susceptibility to the disease would be related to other specific haplotypes, with high frequency in Boxer. Future studies are needed to elucidate whether these differences and haplotypes are related to different phenotypes in immune response and expression gene regulation to L. infantum infections in dogs and their possible application in new treatments and vaccines.Graphical

Reporte de un caso de leishmaniasis canina cutánea y visceral en Querétaro, México.

Leishmania infantum is the causal agent of cutaneous and visceral canine leishmaniasis, a disease widely described in Europe and Latin America. This study describes a case of a canine Canary mastiff breed, born in Mexico that was referred to consult by an alopecic lesion and generalized lymph adenomegaly. Diagnosis of leishmaniasis was established by impression smears of the lesion that showed amastigotes within macrophages. Due to the poor body condition of the animal, euthanasia and necropsy were conducted and samples taken from skin, lymph nodes, liver, kidney, and spleen to perform histological and molecular analysis. In skin, spleen and kidney granulomatous lesions were observed showing amastigotes of Leishmania. The diagnosis of L. infantum was confirmed by using molecular tools. The report of this case suggests the potential risk of this disease in a non-endemic region from Mexico.

Clinicopathological and immunohistochemical features of insulinoma in an adult mixed breed dog

Canine insulinoma is a common non-specific neoplasm with high metastasizing ability. Its epidemiology, diagnosis, and treatment are well described. However, its long-term prognosis is considered poor. We report a rare case of insulinoma in a small-size, mixed-breed adult dog, which presented with a circling walk, seizures, weakness, depressed mental state, and hypoglycemia. Glucose continuous rate infusion, diazepam, and phenobarbital were initiated to stabilize the glycemia and control the convulsion. Blood tests, fine needle aspiration cytology, ultrasound and radiological tests, and histology and immunohistochemical analysis confirmed the diagnosis of insulinoma, emphasizing the relevance of considering it as a differential diagnosis for small canine breeds and younger animals. Further, dogs can be regarded as an experimental animal model for human insulinoma research as they share characteristics.

Genetic Polymorphism and Relationship Analyses of Standard Poodle and Bichon Frise Groups Based on 19 Short Tandem Repeat Loci

Abstract Context: As the increasing number of pet canines, the identification of canine has attracted much attentions in the forensic field, however, the genetic diversities of pet canines still remained unknown. Aims: To explore genetic polymorphisms of 19 short tandem repeat (STR) loci and genetic relationships between the two studied canine groups and reference group. Subjects and Methods: In the present study, genetic polymorphisms of 19 STR loci and a sex-linked zinc finger locus were analyzed in a total of 594 canines in Standard Poodle and Bichon Frise groups from China. Results: A total of 166, 159 alleles were observed in the Standard Poodle, Bichon Frise groups with the corresponding allelic frequencies ranging from 0.0030–0.6108 to 0.0012–0.6148, respectively. The combined discrimination power and probability of exclusion of 19 STR loci in Standard Poodle and Bichon Frise groups were 0.9999999999999497, 0.999962884; and 0.99999999999999995, 0.999965955, respectively. Furthermore, the genetic distances between the two canine groups and Labrador retriever group were calculated, and the results indicated that Standard Poodle and Bichon Frise groups showed a closer genetic relationship, while the two canine groups had distant genetic relationships with Labrador retriever group. The result of population genetic structure revealed that genetic component distributions in the three canine groups were different. The predicted accuracies of the constructed random forest prediction model for three validation sets (25% individuals randomly selected from three populations with 808 individuals) were higher than 0.9, especially for the individuals in validation set from the Bichon Frise group is 1. Conclusions: The 19 STR loci could be used for individual identification, canine breed identification and paternity testing in the two canine groups.

Echocardiographic values in healthy Pugs: Effect of body weight, age, and sex.

Transthoracic echocardiography represents the main noninvasive technique for evaluating cardiac morphology and function in dogs. In dogs with particular somatotypes, such as brachymorphic dogs, breed-specific echocardiographic values are needed for a proper echocardiographic interpretation. Nowadays, the Pug represents one of the most popular brachymorphic canine breeds worldwide. However, data on echocardiographic measurements in this breed are currently limited. We aimed to determine echocardiographic values in a population of apparently healthy Pugs, and to assess the possible effects of body weight (BW), age, and sex on selected echocardiographic variables, with particular emphasis on those related to the left-sided cardiac chambers. Apparently healthy Pugs underwent a full physical examination, a 1-minute six-lead electrocardiogram, and a complete transthoracic echocardiography. Twenty-four echocardiographic variables were measured by combining M-mode, two-dimensional and Doppler modalities, and relative values were determined by applying the statistical procedures recommended by the Clinical and Laboratory Standards Institute. Moreover, the effect of selected demographic variables on echocardiographic measurements was tested using a linear mixed model. The investigation included 86 Pugs. Echocardiographic values were provided for each variable and compared with previous veterinary literature. A statistically significant effect of BW, age, and sex was documented for several of the tested variables. Doppler examination demonstrated a trivial pulmonary regurgitation in 24/86 (27.9%) Pugs. Moreover, a persistent left cranial vena cava was suspected in 4/86 (4.7%) dogs. Echocardiographic features of the Pug were addressed and echocardiographic values were made available for clinical use. Because our findings were obtained using a standardized echocardiographic analysis in a population of 86 healthy Pugs, they may act as a reliable guide for an accurate echocardiographic interpretation in this breed.

Prevalence of dog erythrocyte antigens 1 and 7 in eleven canine breeds in the Republic of Korea

Prevalence of dog erythrocyte antigens 1 and 7 in eleven canine breeds in the Republic of Korea

Immunological and genomic characterization of Ibizan Hound dogs in an endemic Leishmania infantum region

BackgroundThe Ibizan Hound is a canine breed native to the Mediterranean region, where leishmaniosis is an endemic zoonosis. Several studies indicate low prevalence of this disease in these dogs but the underlying molecular mechanism remains unknown.MethodsIn this study, qualitative immunological and genomic profiles of this breed have been analyzed.ResultsOur analysis shows relevant differences between the cytokine serum profile of Ibizan Hound dogs and previously published data from other canine strains. Additionally, several genetic risk variants related to the immune response, regulation of the immune system, and genes encoding cytokines and their receptors have been studied. The most relevant genes that presented such fixed polymorphisms were IFNG and IL6R. Other variants with frequencies ≥ 0.7 were found in the genes ARHGAP18, DAPK1, GNAI2, MITF, IL12RB1, LTBP1, SCL28A3, SCL35D2, PTPN22, CIITA, THEMIS, and CD180. Epigenetic regulatory genes such as HEY2 and L3MBTL3 showed also intronic polymorphisms.ConclusionsOur analysis and results indicate that the regulation of immune responses is different in Ibizan Hounds compared to other breeds. Future studies are needed to elucidate whether these differences are related to the low prevalence of L. infantum infection in the Ibizan Hound.Graphical

Ocular morphologic traits in the American Cocker Spaniel may confer primary angle closure glaucoma susceptibility

Acute primary angle closure glaucoma is a potentially blinding ophthalmic emergency requiring prompt treatment to lower the elevated intraocular pressure in humans and dogs. The PACG in most of canine breeds is epidemiologically similar to humans with older and female patients overrepresented with the condition. The American Cocker Spaniel (ACS) is among the most common breeds observed with PACG development in dogs. This study initially sought to identify genetic risk factors to explain the high prevalence of PACG in ACSs by using a case–control breed-matched genome-wide association study. However, the GWAS failed to identify candidate loci associated with PACG in this breed. This study then assessed intrinsic ocular morphologic traits that may relate to PACG susceptibility in this breed. Normal ACSs without glaucoma have a crowded anterior ocular segment and narrow iridocorneal angle and ciliary cleft, which is consistent with anatomical risk factors identified in humans. The ACSs showed unique features consisting of posterior bowing of iris and longer iridolenticular contact, which mirrors reverse pupillary block and pigment dispersion syndrome in humans. The ACS could hold potential to serve as an animal model of naturally occurring PACG in humans.

Stratification of Companion Animal Life Stages from Electronic Medical Record Diagnosis Data.

Aging is a complex, multifactorial process, where different life stages reflect changes in metabolic processes, immune capacities, and genetic/epigenetic repertoires. With accumulating exposure to environmental stresses and deterioration of physiological functions, body systems become more prone to low-grade chronic inflammation and an increasing range of pathologies. We hypothesized that differential susceptibility to diseases across life span reflects phased changes in an organism's physiological capacity that may highlight when interventions may be appropriately used. Furthermore, the number of life stages may vary between species and be impacted by signalment such as breed. We tested this hypothesis using disease diagnoses data from veterinary electronic medical records containing almost 2 million cats and over 4 million dogs. Bi-clustering (on rates of disease diagnoses) and adaptive branch pruning were used to identify age clusters that could be used to define adult life stages. Clustering among diagnoses were then interpreted within the context of each defined life stage. The analyses identified 5 age clusters in cats and 4 age clusters within each of the 4 canine breed size categories used. This study, using population scale data for two species, one with differential size and life expectancies, is the first to our knowledge to use disease diagnosis data to define adult life stages. The life stages presented here are a result of a data-driven approach to age and disease stratification and are intended to support conversations between clinicians and clients about appropriate health care recommendations.

Immune and Genomic Analysis of Boxer Dog Breed and Its Relationship with Leishmania infantum Infection.

Leishmaniosis, one of the most important zoonoses in Europe, is caused by Leishmania infantum, an intracellular protozoan parasite. This disease is endemic in the Mediterranean area, where the main reservoir is the dog. Several studies indicate a possible susceptibility to L. infantum infection with clinical signs in some canine breeds. One of them is the boxer breed, which shows a high prevalence of disease. In this study, immunological and genomic characterization of serum samples from boxer dogs living in the Mediterranean area were evaluated to analyze the immune response and the possible genetic explanation for this susceptibility. Serum levels of cytokines IFN-γ, IL-2, IL-6, IL-8, and IL-18 were determined by ELISA commercial tests, while the genotyping study was performed using the CanineHD DNA Analysis BeadChip. The results show relevant differences in the serum levels of cytokines compared to published data on other canine breeds, as well as sequence changes that could explain the high susceptibility of the boxer breed to the disease. Concretely, polymorphic variants in the CIITA, HSF2BP, LTBP1, MITF, NOXA1, PKIB, RAB38, RASEF, TLE1, and TLR4 genes were found, which could explain the susceptibility of this breed to L. infantum infection.

Serum levels and genetic variations of cytokines in two canine breeds (Ibizan hound and boxer) in the Mediterranean region, in terms of Leishmania infantum infection

Leishmaniosis, endemic to the Mediterranean area and considered to be the most important zoonosis in Europe, is caused by Leishmania infantum, an intracellular protozoan parasite transmitted by sandflies Phlebotomus. On the one hand, the Ibizan hound, a canine breed native of the Mediterranean region has been described to present a great resistance to the leishmaniosis parasitic infection. On the other hand, other breeds, including boxer, present high prevalence, and severity of the infection. In this study, serum levels of cytokines related to immune response together with the genetic variants found in genes encoding these cytokines have been interrogated in dogs of these two canine breeds (Ibizan hound and boxer) living in the Mediterranean region. A total of 59 apparently healthy dogs were sampled with their corresponding epidemiological data. Serum levels of cytokines were interrogated by ELISA commercial kits and the genetic analysis was carried out with the commercial CanineHD BeadChip and subsequent bioinformatic analysis. The results showed higher levels of IFN-γ, IL-2, and IL-18 and lower levels of IL-8 in Ibizan hound dogs compared to boxer ones. Genomic analysis revealed several genetic variants fixed in the Ibizan hound samples, including IFNG, IL2, IL6R, and IL12RB1 genes, which could explain these differences.