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81.
This study investigated the effects of substituting ear corn silage (ECS) for commercial formula feed on milk production and milk fatty acid profiles in grazing dairy farms during the summer season. A field survey was conducted on five grazing dairy farms in every summer month of 2017, 2018, and 2019. Three of the five farms substituted fresh ECS for the commercial formula feed at a ratio of 2:1 from July of each year (ECS farms). Other farms maintained the same feeding management as before (non‐ECS farms). An interview survey was conducted on each farm to calculate feed intake and milk yield per cow. Feed and milk samples were collected in each survey. Milk compositions and milk fatty acid profiles were determined. The substitution of ECS for the commercial formula feed did not affect milk yield or milk composition, but ECS farms maintained low levels of milk urea compared with non‐ECS farms (p < .01). The ECS substitution also influenced some of the milk fatty acid proportions; C16:0 and C16:1 increased, and trans‐11 C18:1, cis‐9,trans‐11 C18:2, and the sum of polyunsaturated fatty acids decreased, while these fatty acid proportions were maintained in non‐ECS farms throughout the summer season (p < .05).  相似文献   
82.
ABSTRACT:   In order to study the physiological characteristics of neoteny in teleosts, the development of the thyroid axis and digestive tract of the ice fish, Salangichthys microdon (Salmonoidei), were examined using wild caught samples in the Yura River and its estuary. In all developmental stages examined in this study, the digestive tract was straight, and no gastric gland was observed, even in adults. Since these features are only observed in larval stages of a related species, ayu, Plecoglossus altivelis (Salmonoidei), it is suggested that the ice fish retains larval features, not only in appearance but also in internal organs. Additionally, the thyroid axis exhibited a unique characteristic. Until the end of the juvenile stage, thyroid glands remained inactive, and no thyroid stimulating hormone (TSH) cells were observed. Activation of the thyroid gland and the first appearance of TSH cells occurred in adults. Since activation of the thyroid axis was generally known to occur by the time larval have transformed to juveniles in several teleosts, a delayed functioning of the thyroid axis was suggested as a specific characteristic, and probably a major factor contributing to neotenic development of the ice fish.  相似文献   
83.
K. Rikiishi    T. Matsuura    M. Maekawa    K. Noda  K. Takeda 《Plant Breeding》2003,122(2):105-111
Eighty‐four cultivars of barley (Hordeum vulgare) and 95 wild strains (82 of H. spontaneum and 13 of H. agriocrithon) were surveyed for the production of callus, callus growth, and shoot regeneration in cultures derived from immature embryos. All cultivars except for ‘Turkey 381′, induced calli from more than 90% of embryos. On the other hand, the wild lines showed a large variation in the percentage of callus induction from 0 to 100%. Among the cultivars, those with the brittle rachis genotype, bt Bt2, on chromosome 3H, regenerated shoots with a significantly higher percentage than the cultivars with the Bt bt2 genotype. Green shoots were produced in a higher ratio (0.84) in the cultivars than in the wild lines (0.52). Among the lines examined,‘Lenins’ regenerated shoots efficiently (90.4%) and produced the highest number of calli with green shoots per embryo (4.77) followed by ‘Golden Promise’ (3.15). Examination of callus growth and shoot regeneration from embryos at different developmental stages revealed that scutellum development affected the quantity and quality of callus and shoot regeneration.  相似文献   
84.
85.
Radiographic and immunohistochemical analyses were performed in two Holstein heifers with leukocyte adhesion deficiency (BLAD). Severe bone resorption, osteolysis and severe progressive periodontitis in submandibula due to dysfunction of leukocytes in heifers affected with BLAD were demonstrated by radiographic examination. Immunohistochemical analysis of lymph nodes using anti-CD18 monoclonal antibody demonstrated that CD18-positive cells were not found on those from a heifer affected with BLAD, whereas CD18-positive cells were clearly present in lymph nodes from a clinically normal heifer. These characteristic findings support the importance of adherence-dependent leukocyte functions in host defense.  相似文献   
86.
SUMMARY: An inhibitory effect of Kunitz and Bowman-Birk soybean trypsin inhibitors (K- and BB-SBTI) was investigated on tryptic and chymotryptic proteinases of a brood of tiger puffer Takifugu rubripes and yellowtail Seriola quinqueradiata . These assist to comprehend the differences in dietary soybean meal (SBM) utility by fish species and to develop low cost SBM diets with low contents of fish meal. The K-SBTI strongly inhibited tryptic proteinase and weakly inhibited chymotryptic proteinase from the hepatopancreas and intestine including pyloric ceca of the fishes. The BB-SBTI strongly inhibited both proteinases of the fishes. The K-SBTI inhibition for tryptic protease and the BB-SBTI inhibition for tryptic and chymotryptic proteases were relatively constant in tiger puffer with growth of 12–199 g bodyweight. In yellowtail with growth of 7–672 g bodyweight, the K-SBTI inhibition for tryptic protease and the BB-SBTI inhibition for chymotryptic protease were also relatively constant. The BB-SBTI inhibition for yellowtail tryptic protease typically fell in the stage from 7 g to 57 g bodyweight, and then decreased slightly or was maintained constantly. These results indicate that there are different inhibitory modes of K- and BB-SBTI and there is inter- and intraspecific diversity of tryptic protease conformation between the two species.  相似文献   
87.
Neutrophil responses were evaluated in dairy cows at parturition and on 1, 2, 3, 5 and 7 days after they were given dihydroheptaprenol (DHP) (0.5 mg/kg body weight) at parturition. The chemiluminescent index increased significantly (P less than 0.05) from parturition to 1 day after parturition in cows injected with DHP. No significant differences were observed in the number of neutrophils between untreated and DHP-treated groups of dairy cows during the immediate postparturient period.  相似文献   
88.
A Pomeranian dog, 1 year- and 8 month-old neutered female, was presented with persistent respiratory distress and recurrent generalized demodicosis. Physical examination revealed cyanosis, rough respiratory sounds, multifocal alopecia and dermal erosions on the dorsal side of the forelimbs, perineal area and skin around the eyes. A severe diffuse interstitial lung pattern was observed on thoracic radiographs. The blood examination revealed neutrophilia and hypoglobulinemia. Serum immunoglobulin concentrations of IgG and IgA were low. Histopathological examination revealed severe diffuse interstitial pneumonia with Pneumocystis carinii infection. Severe lymphoid depletion was observed in the spleen and other organs with lymphoid follicles consisted mainly of CD3-positive T cells and few cells of B-cell lineage. B-cell hypoplasia with subsequent antibody deficiency was suspected.  相似文献   
89.
The excitability of lateral geniculate cells to orthodromic volleys decreased during saccadic eye movements. This decrease was caused by retinal impulses generated by a quick displacement of the image of the visual field associated with eye movements. This may be a mechanism for saccadic suppression.  相似文献   
90.
Neuronal correlates of eye movements in the visual cortex of the cat   总被引:1,自引:0,他引:1  
About 10 percent of the cells in the visual cortex of awake cats do not respond to stationary parallel stripes in any orientation or to stripes moving across the visual field in any direction at a moderate speed (up to 132 degrees per second), but these cells are either excited or inhibited during saccadic eye movements when the animal faces a patterned visual environment. Of nineteen such cells tested in total darkness, seven discharged in association with eye movements. For saccade-related discharges, the latency during retinal stimulation is typically shorter than the latencey in total darkness.  相似文献   
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