Phylogenetic studies of dogs with emphasis on Japanese and Asian breeds

A Nonsynonymous Substitution of Lhx3 Leads to Changes in Body Size in Dogs and Mice

Lhx3 is a LIM-homeodomain transcription factor that affects body size in mammals by regulating the secretion of pituitary hormones. Akita, Shiba Inu, and Mame Shiba Inu dogs are Japanese native dog breeds that have different body sizes. To determine whether Lhx3 plays a role in the differing body sizes of these three dog breeds, we sequenced the Lhx3 gene in the three breeds, which led to the identification of an SNP in codon 280 (S280N) associated with body size. The allele frequency at this SNP differed significantly between the large Akita and the two kinds of smaller Shiba dogs. To validate the function of this SNP on body size, we introduced this change into the Lhx3 gene of mice. Homozygous mutant mice (S279N+/+) were found to have significantly increased body lengths and weights compared to heterozygous mutant (S279N+/-) and wild-type (S279N-/-) mice several weeks after weaning. These results demonstrate that a nonsynonymous substitution in Lhx3 plays an important role in regulating body size in mammals.

Comparison of hematologic variables between dogs with congenital intrahepatic and extrahepatic portosystemic shunts

BACKGROUND

Dogs with congenital intrahepatic portosystemic shunt (IHPSS) are predisposed to gastrointestinal inflammation, ulceration, and bleeding, unlike dogs with congenital extrahepatic portosystemic shunt (EHPSS). Limited information is available about hematologic differences between dogs with IHPSS and dogs with EHPSS.

OBJECTIVE

Compare hemogram variables between dogs with IHPSS and EHPSS. We hypothesized that hematologic variables would differ between the 2 populations, with a higher frequency and severity of anemia and microcytosis in dogs with IHPSS.

ANIMALS

Twenty-six client-owned dogs with IHPSS and 35 client-owned dogs with EHPSS.

METHODS

Retrospective cross-sectional study. Dogs were included if a CBC was performed before shunt attenuation. Contingency analysis was performed to determine if the frequency of clinical signs and of hematologic variables below the reference range differed between groups. Hematologic and selected biochemical variables were compared between groups using an analysis of covariance with age as a covariate.

RESULTS

Gastrointestinal clinical signs (IHPSS, 81% vs EHPSS, 34%; P = .01), anemia (31% vs 6%; P = .01), microcytosis (77% vs 29%; P = .002), and hypochromia (77% vs 49%; P = .03) were more common in dogs with IHPSS than in dogs with EHPSS. Dogs with IHPSS had lower packed cell volume (34% vs 41%, P = .04), hemoglobin concentration (11.5 g/dL vs 13.7 g/dL, P = .03), mean corpuscular volume (57 fL vs 65 fL; P = .001), and mean corpuscular hemoglobin concentration (32 g/dL vs 33 g/dL; P = .04) than dogs with EHPSS.

CONCLUSIONS AND CLINICAL IMPORTANCE

Dogs with IHPSS had a higher frequency of anemia, microcytosis, and hypochromia and exhibited more gastrointestinal clinical signs.

The Science and Social Validity of Companion Animal Welfare: Functionally Defined Parameters in a Multidisciplinary Field

Social validity refers to the social significance and acceptability of intervention goals, procedures, and outcomes. Animal practitioners, who are often guided by the principles of ABA, lack the benefit of verbal participants (at least with respect to target animals) with which to assess a client's needs and preferences. The study of a learner's welfare is useful for determining areas where intervention is needed or how the learner feels about an intervention that is underway. Three tenets of animal welfare measurement include physiological function, naturalistic behavior, and affect, where affect refers to private events, including emotions, which are a function of the same variables and contingencies responsible for controlling public behavior. The development of new technologies allows us to look "under the skin" and account for subjective experiences that can now be observed objectively. We introduce the reader to tools available from the animal welfare sciences for the objective measurement of social validity from the learner's perspective.

Analysis of Red Blood Cell Parameters in Dogs with Various Stages of Degenerative Mitral Valve Disease

Introduction

Although peripheral blood analysis has become increasingly automated, microscopy is the only available method for the diagnosis of anisocytosis and poikilocytosis. The aims of the study were to compare RBC volume data obtained with two different analysers and by manual assessment of smears and to compare this data between dogs in various stages of heart failure secondary to degenerative mitral valvular (DMV) disease. The impact of diuretic administration on RBC morphology was also assessed.

Material and Methods

Sixty-eight dogs, 56 in different stages of DMV disease and 12 as healthy controls, were studied. Impedance and flow cytometry haematological analyses were performed for each animal. Additionally, two smears were prepared for manual analysis. RBC structure, staining, and size differences were recorded.

Results

There were no significant differences between the blood morphological parameters assessed using haematological analysers nor between dogs receiving diuretic treatment and those not treated. Based on the manual smear, significantly higher erythrocyte anisocytosis was observed in the dogs with symptomatic DMV disease than in the control group.

Conclusion

Haematological analysers based on impedance and flow cytometry provide reliable and comparable morphological results in dogs with heart failure. However, microscopic assessment of blood smears is a more reliable tool to detect erythrocyte anisocytosis.

Genetic diversity and population structure of the Sapsaree, a native Korean dog breed

BACKGROUND

The Sapsaree is a breed of dog (Canis familiaris) native to Korea, which became perilously close to extinction in the mid-1980s. However, with systematic genetic conservation and restoration efforts, this breed was rescued from extinction and population sizes have been gradually increasing over the past few decades. The aim of this study was to ascertain novel information about the genetic diversity, population structure, and demographic history of the Sapsaree breed using genome-wide single nucleotide polymorphism data. We characterized the genetic profile of the Sapsaree breed by comparison with seven foreign dog breeds with similar morphologies to estimate genetic differentiation within and among these breeds.

RESULTS

The results suggest that Sapsarees have higher genetic variance compared with the other breeds analyzed. The majority of the Sapsarees in this study share a discrete genetic pattern, although some individuals were slightly different, possibly as a consequence of the recent restoration process. Concordant results from analyses of linkage disequilibrium, effective population size, genetic diversity, and population structural analyses illustrate a relationship among the Sapsaree and the Tibetan breeds Tibetan terrier and Lhasa Apso, and a small genetic introgression from European breeds. The effective population size of the Sapsaree has contracted dramatically over the past generations, and is currently insufficient to maintain long-term viability of the breed's genetic diversity.

CONCLUSIONS

This study provides novel insights regarding the genetic diversity and population structure of the native Korean dog breed Sapsaree. Our results suggest the importance of a strategic and systematic approach to ensure the genetic diversity and the authenticity of the Sapsaree breed.

Studies of modern Italian dog populations reveal multiple patterns for domestic breed evolution

Through thousands of years of breeding and strong human selection, the dog (Canis lupus familiaris) exists today within hundreds of closed populations throughout the world, each with defined phenotypes. A singular geographic region with broad diversity in dog breeds presents an interesting opportunity to observe potential mechanisms of breed formation. Italy claims 14 internationally recognized dog breeds, with numerous additional local varieties. To determine the relationship among Italian dog populations, we integrated genetic data from 263 dogs representing 23 closed dog populations from Italy, seven Apennine gray wolves, and an established dataset of 161 globally recognized dog breeds, applying multiple genetic methods to characterize the modes by which breeds are formed within a single geographic region. Our consideration of each of five genetic analyses reveals a series of development events that mirror historical modes of breed formation, but with variations unique to the codevelopment of early dog and human populations. Using 142,840 genome-wide SNPs and a dataset of 1,609 canines, representing 182 breeds and 16 wild canids, we identified breed development routes for the Italian breeds that included divergence from common populations for a specific purpose, admixture of regional stock with that from other regions, and isolated selection of local stock with specific attributes.

Evaluation of frequency and intensity of asymptomatic anisocytosis in the Japanese dog breeds Shiba, Akita, and Hokkaido

Microcytosis is observed in healthy Japanese breed dogs. The aim of the study was to evaluate the frequency and intensity of asymptomatic anisocytosis using a three-grade scale in Japanese dog breeds with special emphasis on the following indices: mean cell volume, mean cell haemoglobin, mean cell haemoglobin concentration, and red blood cell distribution width. The retrospective study included analyses of blood morphology and blood smear for clinically healthy Japanese dog breeds Shiba, Akita, and Hokkaido aged from 6 months to 14 years, performed as a part of preventative care. A total of 74 dogs of both sexes were qualified for the study. The group included both neutered and non-neutered animals (Akita – 17 females, 12 males, Shiba – 24 females, 18 males, Hokkaido – 2 females, 1 male). The blood smear revealed significant anisocytosis in 60.8% and mild anisocytosis in 28.4% of the tested dogs – 89.2% in total. Microcytosis was reported for 25.7% of the tested Japanese breed dogs. Reduced mean cell haemoglobin and mean cell haemoglobin concentration were diagnosed in 75.7% and 40.5% of dogs, respectively. Red blood cell distribution width as an anisocytosis indicator exceeded the norm in 12% of the tested dogs. Compared to mixed breed dogs, the Japanese breeds had a reduced mean cell volume, mean cell haemoglobin concentration and significant anisocytosis in the blood smear as well as a higher red blood cell distribution width indicator. Veterinarians should consider these differences when interpreting the results of morphological blood tests.