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81.
Dai ISHIYAMA Kie YAMAMOTO Masato KIKUCHI Fumie MAGATA Kei TAKAHASHI James K. CHAMBERS Kazuyuki UCHIDA Reina FUJIWARA Manabu MOCHIZUKI Hisashi INOKUMA 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2022,84(1):31
A 5-day-old male crossbred beef calf presented with a well-coordinated bilateral hopping gait of the hind limbs. Postmortem CT showed a poorly defined oval-shaped region at the L3–L4 spinal segments, which had high signal intensity on T2 weighted postmortem MRI images. On pathological examination, we identified a large cystic cavity filled with a large amount of cerebrospinal fluid on the cut surface of the spinal region. Histopathological examination revealed that the spinal cord parenchyma was compressed by the cystic structure, and the cystic cavity was lined with a thin layer of discrete ependymal cells, indicating syringohydromyelia. This is the first reported case of a Holstein-Friesian × Japanese Black crossbred calf with solitary syringohydromyelia. Our findings suggest that myelodysplasia with cystic cavities can be suspected by CT, without the need for MRI. 相似文献
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N. MORITSUKA T. NISHIKAWA S. YAMAMOTO N. MATSUI H. INOUE LI Kun-Zhi T. INAMURA 《土壤圈》2013,23(2):169-176
Paddy fields in the southeastern basin of Dianchi Lake have rapidly changed to greenhouses since 1999. A total of 61 surface soil samples, including 43 greenhouse soils, 12 upland soils, and 6 paddy soils, were collected from a flat lowland area mainly used for agricultural production fields in the southeastern basin of Dianchi Lake. Analyses of the soil samples indicated that the greenhouse soils were characterized by a lower organic matter content, lower pH, and higher soluble nutrients than the paddy soils in the area. The lower organic matter content of the greenhouse soils was ascribed to environmental or management factors rather than the clay content of the soil. Accumulation of soluble nutrients, especially inorganic N, was due to over-application of fertilizers, which also caused soil acidification. The average amount of readily available N, P, and K accumulated in the greenhouse soils was estimated to be equal to or higher than the annual input of these nutrients as a fertilizer, indicating that a reduction in fertilizer application was possible and recommended. In contrast, a very low available Si content was observed in the paddy soils, suggesting the need for Si application for rice production. 相似文献
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Tomoaki ONODA Ryuta YAMAMOTO Kyohei SAWAMURA Yoshinobu INOUE Akira MATSUI Takeshi MIYAKE Nobuhiro HIRAI 《Journal of Equine Science》2011,22(2):37-42
Thoroughbred horses are seasonal mating animals, raised in northern regions or countries.
Foals born yearly in spring generally show a typical seasonal compensatory growth pattern,
in which their growth rate declines in the first winter and increases in the next spring.
In this study, a new empirical adjustment approach is proposed to adjust for this
compensatory growth when growth curve equations are estimated, by using 1,633 male body
weights of Thoroughbreds as an illustrating example. Based on general Richards growth
curve equation, a new growth curve equation was developed and fit to the weight-age data.
The new growth curve equation had a sigmoid sub-function that can adjust the compensatory
growth, combined with the Richards biological parameter responsible for the maturity of
animals. The unknown parameters included in the equations were estimated by SAS NLMIXED
procedure. The goodness of fit was examined by using Akaike’s Information Criterion (AIC).
The AIC values decreased from 13,053 (general Richards equation) to 12,794 (the newly
developed equation), indicating the better fit of the new equation to the weight-age data.
The shape of the growth curve was improved during the period of compensatory growth. The
proposed method is one of the useful approaches for adjusting seasonal compensatory growth
in growth curve estimations for Thoroughbreds, and for their management during the
compensatory period. Based on this approach, the optimal growth curve equations can be
estimated also for female body weight of Thoroughbreds or other growth traits affected by
seasonal compensatory growth. 相似文献
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YASUNORI KOYA KIYOSHI SOYANO KAZUHISA YAMAMOTO HIROYUKI OBANA TAKAHIRO MATSUBARA 《Fisheries Science》2002,68(5):1099-1105
The present study investigates the relationship between testicular development and serum steroid hormone levels in captive Pacific herring Clupea pallasii during the first reproductive cycle. The maturity of the testis was divided into five periods based on histological observation. These are early spermatogenic stage (April to July), mid-spermatogenic stage (August to November), late spermatogenic stage (December to March), functional maturation stage (early April) and spent stage (late April). The pattern of seasonal change in gonadosomatic index (GSI) clearly reflected testicular maturity. 11-Ketotestosterone (11-KT) levels increased from October to a peak level (6.58 ± 1.87 ng/mL) in January, and were maintained at this level until March. In contrast, testosterone levels were consistently low, less than 1 ng/mL, at all times. These results suggest that 11-KT is the predominant androgen that controls spermatogenesis in this species. 17,20β-Dihydroxy-4-pregnen-3-one (DHP) showed a single sharp peak (3.38 ± 0.35 ng/mL) in early April of the second year, suggesting that milt production is induced by DHP as in some other teleost species. 相似文献