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71.
Long‐distance transportation has negative impacts on production and health in cattle. Feed and water are routinely deprived from cattle during transportation. We investigated whether niacin supplementation could improve niacin nutrition and mitigate the adverse effect of transportation with feed and water deprivation in steer calves. We also studied the adverse effect of feed and water deprivation in nontransported steer calves. Twelve calves were assigned to feed and water deprivation for 2 days, or full access to feed and water in experiment 1. Ten calves were assigned to 2‐day transportation with feed and water deprivation, or the transportation with feed and water deprivation, but with supplementation of rumen‐protected niacin at 100 g/day per head in experiment 2. Bodyweight was measured and blood was collected for 32 days in each experiment. Feed and water deprivation temporarily decreased serum glucose concentrations and bodyweight gain. Transportation with deprivation of feed and water caused a temporal decrease in bodyweight gain and serum albumin concentration, and a continuous decrease in serum glucose and total cholesterol concentrations, which was suppressed by niacin supplementation. Niacin supplementation increased blood niacin concentration. These results suggest that niacin supplementation mitigates adverse effects of transportation with feed and water deprivation in steer calves. 相似文献
72.
P Pfnuer T Matsui W Grosch H Guth T Hofmann P Schieberle 《Journal of agricultural and food chemistry》1999,47(5):2044-2047
A stable isotope dilution assay was developed for the quantitation of the hazelnut odorant 5-methyl-(E)-2-hepten-4-one by mass chromatography using synthesized [(2)H](2)-5-methyl-(E)-2-hepten-4-one as the internal standard. Application of the method on two batches of commercial hazelnut oils, processed from either roasted or unroasted nuts, revealed 6.4 microg 5-methyl-(E)-2-hepten-4-one per kg of unroasted oil whereas 315.8 microg per kg was determined in the roasted nut oil. The about 50-fold higher amount of 5-methyl-(E)-2-hepten-4-one in roasted hazelnut oil suggested the necessity of a thermal treatment to generate the flavor compound. Pan frying of raw hazelnuts (9 to 15 min) or boiling of the crushed nut material for 1 h in water led to an increase of 5-methyl-(E)-2-hepten-4-one by factors of 600 and 800, respectively, thereby corroborating that the major part of the nut flavorant is formed during heat treatment from a yet unknown precursor in hazelnuts. 相似文献
73.
M Yamada T Matsui Y Kobayashi H Furuoka M Haritani M Kobayashi M Nakagawa 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(7):823-825
Previously we reported that tissue destruction characterized by the presence of karyopyknotic, karyorrhectic and mitotically arrested cells was seen in alimentary epithelial cells and lymphocytes in the lymphoid and hemopoietic systems of cattle experimentally administered with autumn crocus (Colchicum autumnale L.). This report deals with the mechanism of acute cellular injury following experimental autumn crocus poisoning in cattle as demonstrated by the in situ DNA strand break analysis and electron microscopy. The analyses revealed that cellular injury caused by autumn crocus was closely associated with apoptosis. 相似文献
74.
Y Kuroda M Yoshida T Shibahara T Matsui T Nakane H Hara Y Inoshima H Sentsui 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》1999,61(7):749-753
A disease characterized by papules, nodules, vesicles and, rarely, pustules and ulcers on teats was seen among cattle on a farm in Chiba Prefecture, Japan. A virus was isolated by inoculation of fetal bovine lung cell cultures from a vesicle on a teat of an infected cow. The virus was subsequently passaged in fetal bovine lung and muscle cells in which it produced complete cytopathic changes. The virus was identified by physicochemical examinations and electromicroscopic observation as a parapoxvirus. A seroepidemiological survey was performed on antibody to the isolated virus by the agar gel immunodiffusion test. The isolated virus formed a precipitation line which cross reacted with other parapoxviruses isolated previously in Japan. The positive rate was more than 50% among cattle in the Kanto district. The positive rate increased with age. It was suggested that parapoxvirus infection might have already been prevalent among cattle in Japan. 相似文献
75.
Satoshi Hashimoto Kenichi Ueno Kenichi Takahashi Toshiyuki Suzuki Yutaka Itabashi 《Fisheries Science》2010,76(3):529-536
Photosensitivity was observed in the mice used in bioassays of diarrhetic shellfish poisoning. The mice were intraperitoneally
injected with the extracts from the midgut glands of cultured scallops Patinopecten yessoensis gathered in early spring in Funka Bay, Hokkaido, Japan. The injections induced atypical symptoms in the mice within 24 h.
The symptoms included piloerection, substantial eye discharge, swelling of the ears and head, and ear scratching. They were
similar to those reported in studies of photosensitivity caused by pyropheophorbide in the midgut glands of abalones, which
are herbivorous gastropods. The problematic scallops also accumulated a large amount of pyropheophorbide-a. The amount determined with high-performance liquid chromatography was 300–530 μg per 1 g of the homogenate of the midgut
glands. The dose of pyropheophorbide sufficient to cause photosensitivity in a mouse is estimated to be 0.99–2.3 mg per mouse
with 20-g body weight. Moreover, comparative tests in mice showed that the onset of the symptoms required light and a substantial
amount of pyropheophorbide. Therefore, we determined that the observed symptoms were photosensitivity caused by pyropheophorbide.
Scallops, which are suspension-feeding bivalves, can accumulate a large amount of pyropheophorbide in the midgut glands depending
on the habitat environment. 相似文献
76.
Tatsuro Suzuki Takahiro Noda Toshikazu Morishita Koji Ishiguro Shiori Otsuka Jotaro Aii Ayana Nakano Kenjiro Katsu Katsuhiro Matsui Ryoma Takeshima Noriaki Aoki Takashi Hara Takahiro Hara Rie Satoh 《Plant Breeding》2023,142(5):711-720
The concentration of amylose, which is synthesised using granule-bound starch synthase, affects the physical properties of food. However, no studies have focused on starch properties and physical characteristics of low-amylose buckwheat. Here, we hypothesised that low-amylose buckwheat would be useful to produce new buckwheat products because low-amylose characteristics change the texture of buckwheat food. In this study, we bred relatively low-amylose buckwheat compared to wild type and investigated the causative genes of the traits, starch properties and physical properties of noodles. In the GBSSa mutant, the amylose concentration was lower than that in the wild type. Compared with the wild type, the mutant exhibited the following traits: Amylose concentration decreased by approximately 2%, setback in the Rapid Visco Analyzer decreased by 30 points and the physical characteristics of noodles in the sensory analysis were soft and sticky. These results suggest that this trait may be useful for changing the texture of foods. In addition, the mutant is promising for producing new foods with physical characteristics that are different from those of the wild type. 相似文献
77.
Suzuki Toshiyuki Kamiyama Takashi Okumura Yutaka Ishihara Kenji Matsushima Ryoji Kaneniwa Masaki 《Fisheries Science》2009,75(4):1039-1048
Fatty-acid esters of dinophysistoxin-1 (DTX1) in scallops Patinopecten yessoensis, mussels Mytilus coruscus, and toxic dinoflagellate Dinophysis species, collected from Japanese seawater, were analyzed by liquid-chromatography mass spectrometry (LC–MS). Precursor ion
monitoring, multiple reaction monitoring for 18 fatty-acid esters of DTX1, and full-scan MS/MS spectra obtained with a hybrid
triple–quadrupole linear-ion-trap mass spectrometer showed that 14:0, 16:0, and 16:1 esters were the most abundant 7-O-acyl-DTX1 analogues in bivalves. Fatty-acids esters formed by conjugations at hydroxyl positions other than the 7-position
of DTX1 were not detected in the bivalves. DTX1 and okadaic acid-16:0 fatty-acid esters have been reported as the most abundant
ester in bivalves in several previous studies; however, we found that 7-O-16:1-DTX1 was the most abundant ester in some mussels in which 16:1 was more dominant than 16:0 in the free fatty-acid profile.
Comparison between 7-O-acyl-DTX1 and free fatty-acid profiles in the same bivalve samples suggests that polyunsaturated fatty acids are selectively
excluded in enzymatic acylation of DTX1. No 7-O-acyl-DTX1 was detected in any single-cell isolates of D. fortii, D. acuminata, D. mitra, D. norvegica, D. tripos, D. infundibulus, and D. rotundata. 相似文献
78.
79.
80.
Luiz L. Mafra Jr. Daiana Lopes Vanessa C. Bonilauri Hajime Uchida Toshiyuki Suzuki 《Marine drugs》2015,13(6):3920-3935
This study investigates the occurrence of diarrhetic shellfish toxins (DSTs) and their producing phytoplankton species in southern Brazil, as well as the potential for toxin accumulation in co-occurring mussels (Perna perna) and octopuses (Octopus vulgaris). During the spring in 2012 and 2013, cells of Dinophysis acuminata complex were always present, sometimes at relatively high abundances (max. 1143 cells L−1), likely the main source of okadaic acid (OA) in the plankton (max. 34 ng L−1). Dinophysis caudata occurred at lower cell densities in 2013 when the lipophilic toxins pectenotoxin-2 (PTX-2) and PTX-2 seco acid were detected in plankton and mussel samples. Here, we report for the first time the accumulation of DSTs in octopuses, probably linked to the consumption of contaminated bivalves. Perna perna mussels were consistently contaminated with different DSTs (max. 42 µg kg−1), and all octopuses analyzed (n = 5) accumulated OA in different organs/tissues: digestive glands (DGs) > arms > gills > kidneys > stomach + intestine. Additionally, similar concentrations of 7-O-palmytoyl OA and 7-O-palmytoly dinophysistoxin-1 (DTX-1) were frequently detected in the hepatopancreas of P. perna and DGs of O. vulgaris. Therefore, octopuses can be considered a potential vector of DSTs to both humans and top predators such as marine mammals. 相似文献