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Alpha‐melanocyte stimulating hormone (α‐MSH) is one of the main regulators for melanocytes, and the adenohypophysis is one of the major tissues for the synthesis of this hormone. The Silky fowl is a characteristic breed of chicken with hyperpigmentation throughout the body. The involvement of the adenohypophysis in the hyperpigmentation of this breed is not known. In the present study, the proportion of melanocyte stimulating hormone‐immunopositive cells (MSH cells) in the adenohypophysis was immunocytochemically compared between Silky, Red Cornish × New Hampshire (RN) crossbred and Japanese bantam cockerels at 15 weeks of age. After the body and gland were weighed, the adenohypophyseal cells were enzymatically dispersed and immunostained for α‐MSH, and the immunopositive MSH cells were counted. The weights of the body and adenohypophysis were heaviest in the RN crossbred, followed by the Silky and lightest in the bantam cockerels. In contrast, the ratio between adenohypophysis and bodyweight was much larger in the Silky and the bantam than in the RN crossbreed (P < 0.05). The population of MSH cells in the adenohypophysis was larger in the Silky (14.3%) than in the RN crossbreed (8.0%) and the bantam (8.1%) cockerels (P < 0.05). From these results, it was concluded that prepubertal Silky cockerel have numerous MSH cells in the adenohypophysis suggesting a relationship to hyperpigmentation.  相似文献   
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A 12-year-old Thoroughbred gelding exhibited a unilateral exophthalmos on the left side. There had been no other clinical symptoms, such as rhinorrhea, before the first consultation. Clinical, hematologic, plasma biochemical, cytologic, and computed tomography (CT) examinations and complete necropsy were performed. These examinations did not reveal neoplastic lesions. CT images suggested that maxillary and frontal sinuses may have been filled with fluid. Cytologic and pathologic examinations revealed that the maxillary and orbital bones were pushed up with a large amount of the inflammatory fluid effused by chronic sinusitis. The CT and cytologic examinations were of great use for differential diagnosis in this case. This was an unusual case of exophthalmos induced by deformation of the orbital bones resulting from chronic sinusitis.  相似文献   
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We investigated changes in the predicted functions of the rumen bacterial community in Japanese Black beef cattle during fattening. Nine cattle were fed a high-concentrate diet during the early, middle, and late fattening stages consecutively (10–14, 15–22, and 23–30 months of age, respectively). The rumen fluid and solid samples collected at each stage were subjected to sequencing analyses. The sequencing results were clustered and classified into operational taxonomic units (OTUs). Representative sequences and a raw counting table for each OTU were submitted to the Piphillin website. The predicted functions were revealed by the Kyoto Encyclopedia of Genes and Genomes database as the ratio of the total sequence. In the early stage, “Biosynthesis of secondary metabolites” was significantly higher in the fluid fraction than in the solid fraction. “Two-component system” in the middle stage was significantly lower and “Purine metabolism” in the late stage was significantly higher in the fluid fraction than those in the solid fraction. The fluid fraction was significantly correlated with acetic acid, propionic acid, and bacterial metabolism, such as “Biosynthesis of secondary metabolites” and “Sugar metabolism.” Moreover, the solid fraction was correlated with “Purine metabolism” and “Biosynthesis of secondary metabolism”. These results suggest that the rumen bacterial community in Japanese Black beef cattle adapts to changes in rumen conditions by altering their functions in response to a long-term high-grain diet.  相似文献   
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The objective of this study was to examine the health and meat production of cloned sows and their progenies in order to demonstrate the application of somatic cell cloning to the pig industry. This study compared the growth, reproductive performance, carcass characteristics and meat quality of Landrace cloned sows, F1 progenies and F2 progenies. We measured their body weight, growth rate and feed conversion and performed a pathological analysis of their anatomy to detect abnormalities. Three of the five cloned pigs were used for a growth test. Cloned pigs grew normally and had characteristics similar to those of the control purebred Landrace pigs. Two cloned gilts were bred with a Landrace boar and used for a progeny test. F1 progenies had characteristics similar to those of the controls. Two of the F1 progeny gilts were bred with a Duroc or Large White boar and used for the progeny test. F2 progenies grew normally. There were no biological differences in growth, carcass characteristics and amino acid composition among cloned sows, F1 progenies, F2 progenies and conventional pigs. The cloned sows and F1 progenies showed normal reproductive performance. No specific abnormalities were observed by pathological analysis, with the exception of periarteritis in the F1 progenies. All pigs had a normal karyotype. These results demonstrate that cloned female pigs and their progenies have similar growth, reproductive performance and carcass quality characteristics and that somatic cell cloning could be a useful technique for conserving superior pig breeds in conventional meat production.  相似文献   
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Cell numbers of known species of nitrate- and nitrite-reducing bacteria, Selenomonas ruminantium, Veillonella parvula and Wollinella succinogenes , in the rumen of goats (25–30 kg) were estimated by competitive polymerase chain reaction (PCR). The number of S. ruminantium was the largest of the three species examined, and tended to be greater in goats fed a high-concentrate diet (5.6 × 107 cells/mL rumen fluid) than in goats fed a high-roughage diet (1.3 × 107 cells/mL). The number of V. parvula tended to be greater when goats were fed a high-roughage diet (6.7 × 103/mL) than when fed a high-concentrate diet (3.2 × 103/mL). The number of W. succinogenes was below the detectable level (< 1.0 × 102/mL) when a high-concentrate diet was fed, but was significantly increased by feeding a high-roughage diet (1.6 × 103/mL). Addition of potassium nitrate (6 g/day) to the high-concentrate diet tended to increase V. parvula , and significantly increased W. succinogenes , indicating that these two bacteria can be increased by feeding a diet containing nitrate.  相似文献   
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The total amount of collagen, the relative distributions of types I and III collagens in perimysium and endomysium, and the collagen fiber architecture were compared among the pectoralis (PT), iliotibialis lateralis (ITL) and puboischiofemoralis (PIF) muscles in Silky cocks. All of the myofibers in the PT muscle were type IIB, the myofibers in the ITL muscle were divided into type IIA, 41.7% and IIB, 58.3%, and the PIF muscle was composed of type I, 24.6%; IIA, 64.6%; and transitional, 10.8%. The total amount of collagen differed significantly among the PT (2.92 mg/g), PIF (4.20 mg/g) and ITL (8.06 mg/g) material, where only the PIF was a whole muscle with epimysium. On the image analysis of the immunohistochemical preparations, the percentage area of perimysial collagen to the total area in each type differed significantly among the PIF, PT and ITL muscles, where it was 26.8, 50.0 and 74.4% for the type I collagen and 27.4, 32.9 and 61.7% for the type III collagen, respectively. In the scanning electron micrography of the perimysium in macerated preparations, thick bundles of collagen fibers were observed in the ITL muscle, thinner but broad platelets in the PT muscle, and a coarse tissue of thinner collagen fibers in the PIF muscle. However, the endomysial fabric of collagen fibrils was similar among the muscles. Small, transverse collagen fibers, which branched off from the thicker perimysia, occupied narrow interendomysial spaces and separated the primary myofiber fasciculi. The results indicate that the ITL muscle, localized in the distorted and overextended part of the leg and subject to strong external forces, had highly developed perimysial collagen fiber bundles, but the ITL endomysial collagen architecture was similar to that of the PT and PIF muscles.  相似文献   
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The duration of maternally-derived antibodies against three arboviruses was investigated in calves, using the results of arbovirus serosurveillance performed in Kagoshima Prefecture during 2002–2016. The duration of maternally-derived antibodies against Akabane virus (AKAV), Aino virus (AINOV), and Chuzan virus (CHUV) was estimated to be 178 (sensitivity: 0.769, specificity: 0.730), 156 (sensitivity: 0.806, specificity: 0.791), and 156 days of age (sensitivity: 0.845, specificity: 0.814), by receiver operating characteristic analysis. The duration of maternally-derived antibodies against AKAV, AINOV, and CHUV differed 7–14, 22–28, and 20–31 days in the same calf types between the regions far from each other although it was similar between the adjacent regions. The dairy calves showed 6–29 days longer duration than the beef calves rearing in a similar region.  相似文献   
10.
The histochemical profiles of myofibers in Musculus pectoralis (PT) and M. supracoracoideus (SC) fasciculi were compared among Japanese quail strains with large, normal and small body sizes. In male and female adults, both the PT and SC muscles had attained a 2.5–2.7-fold weight gain in the large strain and conversely a 0.43–0.50-fold change in the small strain relative to those of the normal size. The muscles were composed of fasciculi with a central cluster of type IIA fibers surrounded by a peripheral layer of type IIB fibers. In the large strain, the cross sectional area (CSA) of the fasciculus and CSA of the fibers in each type were significantly enlarged compared with those in the normal size, with the exception of the fasciculus in the deep region of the male PT muscle. The hypertrophied type IIA fibers in the large strain showed considerable variation in nicotinamide adenine dinucleotide dehydrogenase activity, some of which might represent a transitional form into type IIB fibers. In the small strain, the fasciculus CSA did not significantly differ from that of the normal size except for the PT surface region of the male. However, fiber atrophy was observed in type IIB fibers of the PT surface region in both sexes, and type IIA fibers of the PT deep region and SC muscle in the small strain male quails. The relative fiber type composition of a fasciculus in each region showed only a slight change across the strains. These results indicate that breast muscle hypertrophy in the large strain could be based mainly on fasciculus and fiber hypertrophy, but muscle atrophy in the small strain is not induced by fasciculus and fiber atrophy.  相似文献   
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