Japanese Shorthorn Research Articles

Current status and its epidemiological consideration of Fasciola and Eurytrema infections in beef cattle of Japan.

To elucidate current status of fasciolosis and eurytremosis in beef cattle of Japan, inspection data of Tokyo Metropolitan Shibaura Slaughterhouse where beef cattle were shipped from all over Japan were analyzed, and questionnaire to farmers was conducted to assess the relationship between recognition of the disease occurrence in one’s own farm and attention to the diseases. The occurrence of fasciolosis and eurytremosis in beef cattle gradually decreased from 18.6% to 0.06% and from 0.58% to 0.02% during the period of 1964 to 2010, respectively. When the current data from 2009 to 2012 were analyzed, the occurrence of fasciolosis was recognized in cattle produced and fattened all over Japan, indicating the disease was prevalent nationwide. While, 97.5% of Eurytrema infection were detected in cattle produced in Okinawa, Shimane and Kagoshima, indicating the disease was endemic in these regions. Higher occurrence (>0.7%) of fasciolosis was observed in minor breeds, such as Japanese Shorthorn. Japanese Black showed 0.09% and 0.05% of occurrence for fasciolosis and eurytremosis, respectively, but F1 crossbred with Japanese Black showed lower occurrence (0.007% and 0.002%, respectively). No tendency of occurrence in the age of cattle at slaughter was recognized, indicating the infections may have occurred at the growing and early fattening stage of cattle. The questionnaire survey revealed that farmers experiencing fasciolosis had more knowledge about the disease, however, factors, such as testing parasite infections and use of anti-Fasciola dewormers, were not affected by the recognition of occurrence.

Bovine-Specific Nucleotide Polymorphisms and mRNA Expression of the Growth Hormone Secretagogue Receptor 1a (GHSR1a) Gene and its Genetic Association with Growth and Carcass Traits

The growth hormone secretagogue receptor 1a (GHSR1a) is involved in many important functions including growth hormone (GH) secretion and appetite regulation and other important functions. We reveal herein, the unravelling of bovine-specific 5’untranslated region (5’UTR) microsatellite polymorphisms, a 3bp-indel in exon 1 (DelR242) and two different kinds of transcripts of the GHSR1a gene (spliced, without a microsatellite with in the 5’UTR (GHSR1a); and non-spliced, with the microsatellite (GHSR1b)). A number of 17 alleles ((TG)10~33 ) in the 5’UTR microsatellite was found in 11 cattle breeds. Furthermore, we found the DelR242 (3R) allele, a truncated 3- arginine residue (3R) (major type: 4 arginine residues (4R)) within the intracellular loop 3 of GHSR1a protein in Japanese Shorthorn with a high frequency of 0.43 compared to the low frequency of 0.00~0.09 in other cattle breeds. We carried out a genetic association study between the 5’UTR microsatellite and growth and carcass traits in 1,285 steers. Statistical analysis revealed that the 5’UTR microsatellite locus had a significant additive effect on carcass weight (CW) and average daily gain (ADG). The 19-TG allele had a significantly desirable effect on these traits. We proposed a translational hypothesis that the association is due to differences in the secondary structure of GHSR1b mRNA among the GHSR1a gene haplotypes. We also examined age-related changes in the expressions of GHSR1a and GHSR1b in many cattle tissues. The GHSR1a mRNA expression in the arcuate nucleus of postweaning calves was more than 10-fold higher than those of pre-weaning calves and cows. In peripheral tissues, there were 3 marked differences in mRNA expression between cattle, humans and mice, as follows: (1) the GHSR1a mRNA expression in the liver is high in cattle and very low in humans and mice; (2) the GHSR1b mRNA expression in the liver is low in cattle and high in humans; (3) the GHSR1b mRNA expression in the pancreas is very high in cattle.

異なる品種のイワテヤマナシ果汁に浸漬させた日本短角種牛肉の理化学特性

異なる品種のイワテヤマナシ果汁に浸漬させた日本短角種牛肉の理化学特性について検討を行った．日本短角種去勢牛の大腿二頭筋をイワテヤマナシ果汁−1，果汁−2，果汁−3および果汁−4に浸漬させて真空包装し，4°Cで冷蔵保存した．浸漬の0，12，96および192時間後に，各サンプルの保水性および加熱前後の色調値の測定，およびテクスチャープロファイル分析を行った．テクスチャープロファイルの各測定項目に有意な差は認められなかった．果汁のpHは果汁−4が他の果汁に比較して有意に高かった．クッキングロスは果汁−2および果汁−3に浸漬させた筋肉が浸漬0時間のものに比較して浸漬192時間で有意に高くなった．加熱前のa*値は果汁−4に浸漬させた筋肉が他の果汁に浸漬させたものに比較して浸漬96時間で有意に高かった．本研究の結果から，イワテヤマナシ果汁への筋肉の浸漬は浸漬前の肉色を維持すること，およびpHの高い品種は筋肉の保水性を維持することが示された．

パイナップル果汁の注入が日本短角種牛肉のテクスチャーおよび保水性に及ぼす影響

パイナップル果汁の注入が日本短角種牛肉のテクスチャーおよび保水性に及ぼす影響

粗飼料多給肥育における日本短角種去勢牛の飼養成績と血中成長ホルモン（GH）およびプロラクチン（PRL）濃度の変化について

粗飼料多給肥育における日本短角種去勢牛の飼養成績と血中成長ホルモン（GH）およびプロラクチン（PRL）濃度の変化について

浸漬液の違いが日本短角種牛肉のコラーゲン性状および酸化に及ぼす影響

浸漬液の違いが日本短角種牛肉のコラーゲン性状および酸化に及ぼす影響

Grazing Affects Exosomal Circulating MicroRNAs in Cattle.

Circulating microRNAs (c-miRNAs) are associated with physiological adaptation to acute and chronic aerobic exercise in humans. To investigate the potential effect of grazing movement on miRNA circulation in cattle, here we profiled miRNA expression in centrifugally prepared exosomes from the plasma of both grazing and housed Japanese Shorthorn cattle. Microarray analysis of the c-miRNAs resulted in detection of a total of 231 bovine exosomal miRNAs in the plasma, with a constant expression level of let-7g across the duration and cattle groups. Expression of muscle-specific miRNAs such as miR-1, miR-133a, miR-206, miR-208a/b, and miR-499 were undetectable, suggesting the mildness of grazing movement as exercise. According to validation by quantitative RT-PCR, the circulating miR-150 level in the grazing cattle normalized by the endogenous let-7g level was down-regulated after 2 and 4 months of grazing (P < 0.05), and then its levels in housed and grazing cattle equalized when the grazing cattle were returned to a housed situation. Likewise, the levels of miR-19b, miR-148a, miR-221, miR-223, miR-320a, miR-361, and miR-486 were temporarily lowered in the cattle at 1 and/or 2 month of grazing compared to those of the housed cattle (P < 0.05). In contrast, the miR-451 level was up-regulated in the grazing cattle at 2 months of grazing (P = 0.044). The elevation of miR-451 level in the plasma was coincident with that in the biceps femoris muscle of the grazing cattle (P = 0.008), which suggests the secretion or intake of miR-451 between skeletal muscle cells and circulation during grazing. These results revealed that exosomal c-miRNAs in cattle were affected by grazing, suggesting their usefulness as molecular grazing markers and functions in physiological adaptation of grazing cattle associated with endocytosis, focal adhesion, axon guidance, and a variety of intracellular signaling, as predicted by bioinformatic analysis.

Genetic structure and relationships of 16 Asian and European cattle populations using DigiTag2 assay.

In this study, we genotyped 117 autosomal single nucleotide polymorphisms using a DigiTag2 assay to assess the genetic diversity, structure and relationships of 16 Eurasian cattle populations, including nine cattle breeds and seven native cattle. Phylogenetic and principal component analyses showed that Bos taurus and Bos indicus populations were clearly distinguished, whereas Japanese Shorthorn and Japanese Polled clustered with European populations. Furthermore, STRUCTURE analysis demonstrated the distinct separation between Bos taurus and Bos indicus (K=2), and between European and Asian populations (K=3). In addition, Japanese Holstein exhibited an admixture pattern with Asian and European cattle (K=3‐5). Mongolian (K=13‐16) and Japanese Black (K=14‐16) populations exhibited admixture patterns with different ancestries. Bos indicus populations exhibited a uniform genetic structure at K=2‐11, thereby suggesting that there are close genetic relationships among Bos indicus populations. However, the Bhutan and Bangladesh populations formed a cluster distinct from the other Bos indicus populations at K=12‐16. In conclusion, our study could sufficiently explain the genetic construction of Asian cattle populations, including: (i) the close genetic relationships among Bos indicus populations; (ii) the genetic influences of European breeds on Japanese breeds; (iii) the genetic admixture in Japanese Holstein, Mongolian and Japanese Black cattle; and (iv) the genetic subpopulations in Southeast Asia.

Grazing-induced changes in muscle microRNA-206 and -208b expression in association with myogenic gene expression in cattle.

To investigate the roles of microRNAs (miRNAs) in muscle type conversion, the effects of 4 months of grazing on the expression levels of miRNAs and mRNAs associated with skeletal muscle development were analyzed by quantitative RT-PCR using the Biceps femoris muscle of Japanese Shorthorn cattle. After 4 months of grazing, the expression of muscle fiber type-associated miR-208b was higher in the grazed cattle than in the housed. In concordance with the pattern in miR-208b expression, the expression of MyoD, a myogenic regulatory factor associated with the shifting of muscle property to the fast type, was lower in the grazed cattle after 4 months of grazing than in the housed cattle. In addition, the expression of MyHC-2x (a fast type) was higher in the housed cattle than in the grazed, after 4 months of grazing. During the grazing period, miR-206 expression decreased in the housed cattle, whereas expression in the grazed cattle did not change, but rather remained higher than that of the housed cattle even at 3 months after the grazing ended. These miRNAs including miR-206 persisting with muscles of grazed cattle may be associated with regulation of muscle gene expression during skeletal muscle adaptation to grazing.

Overdominance effect of the bovine ghrelin receptor (GHSR1a)-DelR242 locus on growth in Japanese Shorthorn weaner bulls: heterozygote advantage in bull selection and molecular mechanisms.

Ghrelin and the ghrelin receptor (GHSR1a) are involved in growth hormone secretion, food intake, and several other important functions. Ghrelin acts on GHSR1a and induces signal transduction via the Gαq subunit. In our previous study, we identified the DelR242 (3R) allele, a truncated 3-arginine residue (3R) [major type: 4 arginine residues (4R)] of the third intracellular loop of GHSR1a, with a high frequency in Japanese Shorthorn bulls (0.43) but with a low frequency in other cattle breeds (0.00–0.09). To further investigate the reasons for the higher frequency of the 3R allele, we performed several experiments. In this study, we found a significant sex difference in the frequency of the 3R allele. Statistical analysis revealed a significant overdominance effect of the DelR242 locus on growth in Japanese Shorthorn weaner bulls. However, additive/dominance/overdominance effects of the 3R allele on carcass traits in adult steers and dams were not significant. The mode of the overdominance effect was estimated to be solely controlled by the single DelR242 locus without any other linked loci using linkage disequilibrium analysis in GHSR1a. These results indicated that 4R/3R heterozygotes had a selective advantage in weaner bulls because of their higher average daily gain than homozygotes. We discussed possible molecular mechanisms involved in the overdominance effect of the DelR242 locus on these traits in weaner bulls using a structural model of the complex consisting of a GHSR1a dimer and Gαq.

浸漬液のpHが日本短角種牛肉の理化学特性に及ぼす影響

浸漬液のpHが日本短角種牛肉の理化学特性に及ぼす影響について検討を行った．日本短角種去勢牛の大腿二頭筋を，pHが異なる等量の緩衝液に，それぞれ浸漬させて真空包装し，4℃で保存した．24時間後に各浸漬させた筋肉および浸漬なしの筋肉（対照肉）の保水性を求めた．また，加熱前に各筋肉および浸漬液の色調を測定し，加熱後に各筋肉のテクスチャープロファイル分析を行った．浸漬液のpHはテクスチャープロファイル分析の各項目に有意な影響を及ぼさなかった．クッキングロスは対照肉が浸漬させたものに比較して有意に低かったが，トータルロスでは対照肉とpH 6.86緩衝液に浸漬させたものとの間に有意な差は認められなかった．筋肉のL*値はRO水に浸漬させた筋肉が他のものに比較して有意に高かった．筋肉のa*値は浸漬させた筋肉が対照肉に比較して有意に低かった．pH 4.01緩衝液のa*値およびK/S525は他の浸漬液に比較して有意に低かった．

浸漬液および浸漬時間の違いが日本短角種牛肉の理化学特性に及ぼす影響

浸漬液および浸漬時間の違いが日本短角種牛肉の理化学特性に及ぼす影響

Benign multicystic peritoneal mesothelioma associated with partial spontaneous regression in an aged cow

This article describes a benign multicystic peritoneal mesothelioma presenting partial spontaneous regression in a 16-year-old Japanese Shorthorn cow, which exhibited innumerable fluid-filled cysts (<20 cm diameter) distributing throughout the serosal surface of the peritoneal cavity on postmortem examination. Each cyst was further subdivided into several daughter cysts. On histopathology, these cystic structures consisted of multiloculated irregular spaces that contained serous fluid positive for Alcian blue stain and periodic acid-Schiff (PAS) reaction and were lined by neoplastic mesothelial cells arranged in a single to multicell layers. In some places, neoplastic cells exhibited a tubular, papillary, villous-like, or peninsular growth pattern. Neoplastic cells exhibited mild anisocytosis and anisokaryosis with very low mitotic rate. Immunohistochemically, all or some of neoplastic cells were positive for cytokeratin or vimentin, respectively. Some smaller cysts represented abundant sclerotic stroma in association with fewer shrunken neoplastic cell-lined tubules enclosed by dense fibrocollagenous stroma, collagen fiber collapse, infiltrates of lymphocytes and macrophages disposing of collagen fiber debris, and many capillaries. These findings raised the likelihood that a specific process operating partial spontaneous regression might have been implicated in this tumor. The precise mechanism underlying this phenomenon remains uncertain, although the role of abundant sclerotic stroma was highlighted.

Myostatin alters glucose transporter-4 (GLUT4) expression in bovine skeletal muscles and myoblasts isolated from double-muscled (DM) and normal-muscled (NM) Japanese shorthorn cattle

The purpose of this study was to determine whether myostatin alters glucose transporter-4 (GLUT4) expression in bovine skeletal muscles and myoblasts isolated from double-muscled (DM) and normal-muscled (NM) Japanese Shorthorn cattle. Plasma concentrations of glucose were lower in DM cattle than in NM cattle (P < 0.01). The expression of GLUT4 messenger RNA (mRNA) in the skeletal muscle ex vivo and in myoblasts at 72 h after differentiation in vitro was higher in DM cattle than in NM cattle (P < 0.01). In contrast, the NM and DM cattle did not differ with respect to skeletal muscle expression of GLUT1 and myocyte enhancer factor-2c (MEF2c), a transcription factor of GLUT4. In differentiated myoblasts, the expression of GLUT1, GLUT4, and MEF2c mRNAs was greater in DM cattle than in NM cattle (P < 0.01). In the presence and absence of insulin, glucose uptake in myoblasts was increased in DM cattle relative to that of NM cattle (P < 0.01). The addition of myostatin decreased the expression of GLUT4 and MEF2c mRNAs in DM myoblasts (P < 0.05). Results of the present study suggest that myostatin inhibits the expression of GLUT4 mRNA possibly via MEF2c and that the greater ability of the DM cattle to produce muscle relative to the NM cattle may be due to their greater sensitivity to insulin and greater use of glucose.

Case report: simultaneous occurrence of multifocal cortical hypoplasia and degeneration in the cerebellum and systematic cerebrovascular intimal fibroelastosis in a calf

The etiology of cerebellar hypoplasia is often uncertain in one litter or single animals. A spontaneous case of cerebellar cortical hypoplasia and degeneration with a topographic difference in the involvement of lesions is herein described in a 6-month-old female Japanese Shorthorn calf with a history of neurologic signs beginning at birth. The calf was euthanatized because of unfavorable prognosis. The most significant gross lesions were present in the cerebellum, where the cerebellar folia of the vermis and flocculonodular lobe were smaller in size than normal. Upon histopathologic examination of the cerebellum, the whole rostral vermis, some lobules of the caudal vermis, and the whole flocculonodular lobe displayed bilaterally symmetric cortical hypoplasia characterized by narrowing of the molecular layer, absence of Purkinje cells, and hypocellularity of the granular layer. Additional intracerebellar findings consisted of a varying degree of Purkinje cell loss leaving empty baskets in some folia of the well-developed lobules at the caudal vermis and the presence of areas displaying bilateral myelin deficiency in association with spongy vacuolar changes in the deep cerebellar nuclei. Other significant findings included an ischemic cell change of the cerebrocortical pyramidal neurons in the Sylvian gyrus of the left parietal lobe and systematic intimal fibroelastic hyperplasia similar to arterio(lo)sclerosis in the cerebral and cerebellar blood vessels. These histopathologic evidences raise one possibility that a putative chronic hypoxemia due to systematic cerebrovascular alteration might have been implicated in the development of multifocal cerebellar cortical hypoplasia and degeneration in this calf, though final affirmation of this notion should await further investigations of similar or identical cases.

黒毛和種と日本短角種の枝肉形質にCW-1，CW-2およびGHの各遺伝子多型が及ぼす影響

黒毛和種と日本短角種の枝肉形質にCW-1，CW-2およびGHの各遺伝子多型が及ぼす影響

Comparison of Urinary Cortisol Levels in Holstein and Japanese Shorthorn Cows in Response to Breeding System and Heat Stress

This study was performed to compare the stress hormone levels of Holstein and Japanese Shorthorn cows in response to the breeding system and heat stress. A total of 50 Holstein and 17 Japanese Shorthorn cows were used. The breeding system and heat stress were classified into grazing and indoor housing groups, and into the Temperature-Humidity Index (THI) ≥72 and THI <72, respectively. For Holstein cows, the urinary cortisol levels were higher in the grazing group than in the indoor housing group. In contrast, for Japanese Shorthorn cows, the urinary cortisol levels were higher in the indoor housing group than in the grazing group. In the grazing group, the urinary cortisol levels were higher in Holstein cows than in Japanese Shorthorn cows. In the grazing group of Holstein cows, the urinary cortisol levels were higher in the THI ≥72 group than in the THI <72 group. On the other hand, in Japanese Shorthorn cows, the urinary cortisol levels did not differ between the 2 THI groups, regardless of the breeding system. This study suggested that Holstein and Japanese Shorthorn show differing stress responses to breeding system and (or) heat stress.

パイナップル果汁への浸漬時間が日本短角種牛肉の理化学特性に及ぼす影響

パイナップル果汁への浸漬時間が日本短角種牛肉の理化学特性に及ぼす影響

日本短角種経産牛の放牧後の肥育期間と筋肉の理化学特性との関係

日本短角種経産牛の放牧後の肥育期間と筋肉の理化学特性との関係

Individual difference in serum oxytocin concentrations of calves and the correlation with those in dams

We examined individual differences in serum oxytocin concentrations (OT) of calves, and assessed whether these differences were correlated with their dams' milk and serum OT. Eight Holstein (H), nine Japanese Shorthorn (JS), and six Japanese Black (JB) calves were examined. Blood was collected three times during the first month in H calves, while their dams' blood was collected three times prior to parturition. Milk was collected twice after parturition from H cows. Blood from JS and JB calves were collected at 1 and 4 months old, while of their dams only once before parturition. Serum OT in H calves at 7 days old was significantly correlated with that at 30 days. Serum OT of JS calves at 1 month old was significantly correlated to that at 4 months, while of JB calves was also positively correlated (r = 0.70). Serum OT of calves showed significant individual differences in each breed. Serum OT of calves was not correlated with the milk OT of dams, except for 3-day-old calves that fed on their dams' milk. We concluded that although serum OT differed among individuals, this difference was stable within each individual and not affected by the serum OT of the dams.