Native Horses Research Articles

Phylogenetic Relationships among Japanese Native and Alien Horses Estimated by Protein Polymorphisms.

A total of 2, 415 blood samples from 8 populations of Japanese native horses, 18 populations of Asian native horses and 8 breeds of European horses (race-horses, draft-horses and ponies) collected since 1971 were electrophoretically examined at 33 biochemical genetic loci. Gene diversity within populations or breeds measured by the proportion of polymorphic loci (Ppoly) and the expected average heterozygosity per individual (H) was observed to be higher in the Mongolian native horses than in other populations or breeds, and in the Tokara horse of Japan was on the lowest level. Gene diversity between populations or breeds was evaluated by the principal component analysis (PC). It was also measured by computing the Nei's standard genetic distances from the allele frequency data, and the dendrograms were drawn from the genetic distance matrix by the unweighted-pair-group (UWPG) method and the neighbor-joining (NJ) method for estimating the phylogenetic relationships among the horse populations or breeds. The results revealed that the horse populations or breeds were roughly classified into four clusters, that is, Asian native horses, European race-horse breeds, European draft-horse breeds and European pony breeds. The cluster of Asian native horses included some subclusters of Mongolian native horses, south and southeast Asian native horses, Indonesian native horses, and Japanese native horses, although the Batak horse of Indonesia was observed to diverge from the subcluster of Indonesian native horses and the Tokara and Noma horses of Japan diverged remarkably from the subcluster of Japanese native horses in gene constitution. Such diversifications are postulated to be on account of the effect of random genetic drift and/or a bottle-neck effect resulting from their geographic isolation and small reproductive population size. The Mori-Hayashida's two-wave immigration hypothesis for formation of eight local populations of the Japanese native horses can not be supported from our genetic data.

Characteristics of Grazing Behaviour in Tokara Native Horses and Japanese Black Cows Grazed Separately on Native Pastures

Characteristics of Grazing Behaviour in Tokara Native Horses and Japanese Black Cows Grazed Separately on Native Pastures

北海道和種馬にみられた線維性骨異栄養症の臨床病理学的観察

北海道和種馬にみられた線維性骨異栄養症の臨床病理学的観察

Intake, Digestibility and Nutritive Value of Sasa nipponica in Hokkaido Native Horses.

Intake, Digestibility and Nutritive Value of Sasa nipponica in Hokkaido Native Horses.

Changes of eating pattern of Hokkaido native horses in winter

Changes of eating pattern of Hokkaido native horses in winter

Changes of eating pattern of Hokkaido native horses in winter

Changes of eating pattern of Hokkaido native horses in winter

Phylogenetic Relationship of Cheju Native Horses by Mitochondrial DNA Analysis

Phylogenetic Relationship of Cheju Native Horses by Mitochondrial DNA Analysis

Population Differentiation of Japanese Native Horses by DNA Fingerprinting.

Oligonucleotide probes specific for simple tandem repeat sequences produce individual specific DNA fingerprints in man and animal species tested so far. In the present study, a polynucleotide (TG)n was used to investigate DNA fingerprint variability in three breeds (Thoroughbred, Tokara horse and Noma horse) in order to clarify the relationships among Japanese native horses by using DNA fingerprinting (DFP). Estimates of the probabilities of finding identical fingerprints in two unrelated individuals of different breeds were in the range from 2.1×10-1 to 3.6×10-5.Similarities in DFP patterns between individuals were estimated by using the band sharing (BS) value. From the BS values, individuals within breeds tended to be more similar to each other with regard to DFP pattern than to individuals of other breeds. Furthermore, the genetic distance among the horse breeds was estimated as the mean number of nucleotide substitutions per nucleotide site. All individuals of three different ferent breeds were distributed into particular clusters and the Tokara horse was far from other breeds. DFP analysis can therefore be effectively used to assess the genetic relationship among breeds of horses.

傾斜樹林地に冬季間放牧した北海道和種馬の牧区内位置

傾斜樹林地に冬季間放牧した北海道和種馬の牧区内位置

東亜と日本在来馬の起源と系統

東亜と日本在来馬の起源と系統

Hemoglobin Type Analysis of Ryukyu and Tokara Native Horses

Hemoglobin Type Analysis of Ryukyu and Tokara Native Horses

An additional classification for equine Hb-.ALPHA. types.

Equine hemogulobin-α (Hb-α) types have been classified into ten genotypes using the four haploytypes of A, AII, BI and BII which have been identified internationally. However, Hb-α types with the new haplotype not being able to be applied to the ten known Hb-α types, were detected in Hokkaido native horses. These new variants were also observed in other foriegn breeds of horses as well. In addition, since all of these new Hb-α types are clearly controlled by the same new haplotype, this new haplotype was given the name of CII, and then, CI as another haplotype compared with the supposed haplotype CII type. At the same time, an additional classification for the Hb-α types with the new haplotype was demonstrated, and then, some problems for typing them and the differece in the Hb types between donkeys and horses were also discussed.

Extinctions on Ice

Mass extinctions of North American mammals at the end of the last Ice Age continue to draw scientific attention and debate It is a paleontological mystery that falls under the heading Now you see them, now you don't. last Ice Age, or Pleistocene epoch, extended from 1.6 million to 10,000 years ago, yet not until its final two millennia did large numbers of North American animals make their swan song. In a blip of time in the 3.5billion-year history of life on earth, the fossil evidence indicates that 35 classes of mammals became extinct in North America and most vanished altogether. What caused the virtually simultaneous demise of mammoths, mastodons and saber-toothed cats, not to mention native horses, ground sloths, native camels, armadillo-like glyptodonts, giant peccaries, mountain deer, giant beavers, four-pronged antelopes, dire wolves, native lions and giant short-faced bears? Scientists have grappled with this question for nearly two centuries, and, as evidenced by a recent symposium at the Smithsonian Institution in Washington, D.C., the debate is not about to cool down. There is broad agreement that the extinctions occurred 12,000 to 10,000 years ago, and probably more precisely about 11,000 years ago. But the cause of this disappearing act is attributed either to hunting by early inhabitants of the New World, climate change or some combination of the two. The seemingly incredible notion I have defended is that prehistoric people obliterated hundreds of species of large mammals, and even more species of smaller animals as oceanic islands were populated, in a very brief moment early in the colonization of the globe, says ecologist Paul S. Martin of the University of Arizona in Tucson.

日本•韓国在来馬の免疫学的特性に関する研究

日本•韓国在来馬の免疫学的特性に関する研究

主成分分析による沖縄在来馬と宮古改良馬の体型に関する解析

主成分分析による沖縄在来馬と宮古改良馬の体型に関する解析

Feeding the sick horse

The present study is the first report that investigated the seroprevalence of Toxoplasma gondii infection in domestic horses in various prefectures of Japan and analyzed risk factors for seropositivity. We performed a latex agglutination test for riding/racing horses from 11 prefectures in Japan (783 samples) and 4 groups of Japanese native horses (254 samples). The total seroprevalence of anti-T. gondii antibody in horses examined in this study was 4.24% (44/1037). As for riding/racing horses, we did not find a statistically different T. gondii seroprevalence between sampling prefectures. In contrast, seroprevalence of T. gondii in older horses (> 21 years) was significantly higher than that in younger horses (< 5 years and 11–15 years). There was no significant difference in T. gondii seroprevalence between riding/racing horses and Japanese native horses. Logistical regression analysis revealed that age, but not sex and usage, is a significant risk factor of T. gondii infection for domestic horses in Japan. These findings suggest that domesticated horses in Japan can be horizontally infected with T. gondii by ingestion of food or water contaminated with oocysts.

Classification of Body Size and Shape of Five Native Horses Bred in the Kyushu Region

Body size and shape of five native horses of Tokara, Taishu, Amami, Ryukyu and Misaki horse which have been bred in the Kyushu region were studied by multivariate analysis with principal component analysis and cluster analysis for thirteen body measurements of those horses.1. The first principal component with size factor contributed to the separation of Misaki horse from other four native horses.2. The second principal component with shape factor contributed to the separation to the sex differential in Tokara, Taishu, Amami and Ryukyu horses.3. The third principal component with shape factor contributed to the separation to the sex differential in Misaki horse.4. Five native horses were classified in two groups, Misaki and other four native horses, by cluster analysis.

Sero-Epidemiological Study on Equine Influenza in Japan

A serological survey was conducted on horse sera collected for 7 years just before the first outbreak of equine influenza (EI) infection in Japan in 1971. No antibodies against the A/Equi-1/Prague/56 (equi-1) and A/Equi-2/Miami/63 (equi-2) strains of EI virus were detected in any of the sera of 452 native horses when employing hemagglutination inhibition (HI) and complement fixation (CF) tests against viral (V) antigen. On the contrary, of the 80 imported horses, 48 (60.0%) had HI titers of 1:8 or higher against equi-1 and 23 (28.8%) against equi-2. In the CF-V test 42.6% of the horses showed titers of 1:4 or higher against equi-1 antigen and 42.9% against equi-2 antigen. However, all the test sera of the native and imported horses were negative (less than 1:4) in CF tests against soluble human influenza antigen. Epidemiological analysis was carried out to clarify the relationship between the history and the presence of serum antibody against EI viruses in individual imported horses.

正誤表（野沢謙）

正誤表（野沢謙）

正誤表（江崎孝三郎）

正誤表（江崎孝三郎）