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1.
Muscle biopsies were taken from the middle gluteal muscle of 28 Standardbred trotters, 3-4 years of age. The 13 horses in Group T were trained consistently from 18 months of age, whereas the 15 horses in Group UT were not exposed to any systematic training before 3 years of age. Group T horses had a lower percentage of Type IIB fibres (31%) than did Group UT horses (39%). Citrate synthase (CS) activity, representing oxidative capacity, was higher in Group T (72 mmol kg-1 min-1) than in Group UT (47 mmol kg-1 min-1). Biopsies were taken from 4 horses in each group when they were foals and then annually until 3-4 years of age. Results from this study indicate that regular training of Standardbreds from 18 months of age resulted in increased CS activity and a decrease in the percentage of Type IIB fibres. This study shows that training, not growth, is the main factor that induces a high oxidative capacity and a high Type IIA/IIB fibre ratio in muscle of Standardbred trotters. 相似文献
2.
During recent years it has been evident that a number of gastrointestinal hormones are potent calcitonin secretagogues, and it has been suggested that a gastrointestinal-thyroid C cell system exists as a part of post prandial calcium homeostasis. In the present study the hypocalcaemic effect of pentagastrin, a synthetic peptide with gastrin effects, was studied in lactating cows. Intravenous infusion of pentagastrin caused marked hypocalcaemia and hypophosphataemia in the cows. Thyroidectomy completely abolished the hypocalcaemic and hypophosphataemic effects of the peptide. The results thus suggested that the effects of the peptide were due to release of endogenous calcitonin. 相似文献
3.
Fredrik I. Grünenfelder Dominik Weishaupt Ron Green Frank Steffen 《Veterinary radiology & ultrasound》2005,46(2):91-96
Fibrocartilaginous embolization (FCE) of the spinal cord is a common disease in large breed dogs. There are only a few reports about this entity in small breed dogs and it has never been reported in chondrodystrophic breed. For definitive diagnosis histopathologic examination is necessary. Magnetic resonance imaging (MRI) as a potential diagnostic tool for intravitam diagnosis of FCE has been mentioned before, but results have not been reported so far. This report describes the neurological findings and MRI results in three small breed dogs, including a Pekingese dog, with FCE of the spinal cord. The disease was suspected in two animals based upon clinical and MRI-appearance and confirmed in the third by histopathological examination. In all three cases, similar focal intramedullary lesions, consisting of hyperintensive signals on T2-weighted images, were detected. Based on these findings, high-field MRI may be used as an antemortem tool for the diagnosis of FCE. It is also shown that FCE can occur in chondrodystrophic dogs. 相似文献
4.
Estimation of Crown Temperature of Winter Wheat and the Effect on Simulation of Frost Tolerance
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T. Persson A. K. Bergjord Olsen L. Nkurunziza E. Sindhöj H. Eckersten 《Journal of Agronomy and Crop Science》2017,203(2):161-176
Accurate estimation of winter wheat frost kill in cold‐temperate agricultural regions is limited by lack of data on soil temperature at wheat crown depth, which determines winter survival. We compared the ability of four models of differing complexity to predict observed soil temperature at 2 cm depth during two winter seasons (2013‐14 and 2014‐15) at Ultuna, Sweden, and at 1 cm depth at Ilseng and Ås, Norway. Predicted and observed soil temperature at 2 cm depth was then used in FROSTOL model simulations of the frost tolerance of winter wheat at Ultuna. Compared with the observed soil temperature at 2 cm depth, soil temperature was better predicted by detailed models than simpler models for both seasons at Ultuna. The LT50 (temperature at which 50 % of plants die) predictions from FROSTOL model simulations using input from the most detailed soil temperature model agreed better with LT50 FROSTOL outputs from observed soil temperature than what LT50 FROSTOL predictions using temperature from simpler models did. These results highlight the need for simpler temperature prediction tools to be further improved when used to evaluate winter wheat frost kill. 相似文献
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6.
Thomas H Hansen Kristian H Laursen Daniel P Persson Pai Pedas Søren Husted Jan K Schjoerring 《Plant methods》2009,5(1):12-11
Background
Quantitative multi-elemental analysis by inductively coupled plasma (ICP) spectrometry depends on a complete digestion of solid samples. However, fast and thorough sample digestion is a challenging analytical task which constitutes a bottleneck in modern multi-elemental analysis. Additional obstacles may be that sample quantities are limited and elemental concentrations low. In such cases, digestion in small volumes with minimum dilution and contamination is required in order to obtain high accuracy data. 相似文献7.
Lars Helge Stien Fredrik Manne Antti Kause Anders Kiessling 《Aquaculture (Amsterdam, Netherlands)》2006,261(2):695-705
The goal of this paper is to propose and evaluate automated image analysis methods for describing muscle cutlets in rainbow trout. The proposed automated image analysis methods were tested on a total of 983 scanned images of trout cutlets, and included quality traits such as fat percentage, flesh colour and the size of morphologically distinguishable subparts of the cutlet. A sub-sample of 50 images was randomly selected for manual segmentation of the cutlet, the dorsal fat depot and the red muscle and regions. The identification of these regions by manual and automatic image analysis correlated strongly (r = 0.97, r = 0.95 and r = 0.91, respectively). The estimated fat percentage obtained from image analysis, based on the area of visible fat and the colour of the cutlet flesh, correlated well with chemical fat percentage measured by mid-infrared transmission spectroscopy (MIT) (r = 0.78). The automated image analysis methods are therefore a reliable means of predicting the fat percentage of trout cutlets. Principal component analysis (PCA) loading plots were used to identify subsets of variables from the image analysis of special significance for further studies; cutlet area, dorsal fat depot area, red muscle area, back height, cutlet width, and width of left and right abdomen wall were among the variables selected. PCA loading plots of different colour variables indicated that simple statistical coefficients such as percentiles and mean values can be used to quantify different aspects of flesh colour. In conclusion, the methods presented here provide a powerful toolbox for describing important morphological structures and quality traits of trout cutlets. 相似文献
8.
The heparin antagonist protamine inhibits bone resorption. In the present study protamine was given i.v. at a dose of 10 mg/kg to goats and sheep in various stages of pregnancy and lactation. It is known that bone resorption increases as pregnancy progresses. In sheep maximum in bone resportion is reached at early lactation. The hypocalcemic response to protamine followed a similar course. The slightest decrease in serum calcium was obtained during early pregnancy and the greatest during late pregnancy and early lactation. Protamine increased serum inorganic phosphorus. The increase was most pronounced during early pregnancy. Protamine did not significantly change serum magnesium.Five lactating ewes were given 25000 i.u./kg of vitamin D3. Serum calcium increased and the hypocalcemic response to protamine was greater after vitamin D3 administration than before.The results showed that the hypocalcemic response to protamine can be used as an indicator of the role of bone resorption in calcium homeostasis in various physiological situations. 相似文献
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10.
Kaeoket K Persson E Dalin AM 《Journal of veterinary medicine. A, Physiology, pathology, clinical medicine》2003,50(4):169-178
This study investigates the distribution of leucocytes, CD2+, CD4+, CD8+ lymphocyte subpopulations and MHC class II expressing cells in the sow endometrium following post-ovulatory insemination in relation to clinical findings and pregnancy outcome. Crossbred multiparous sows were inseminated once either at 15-20 h after ovulation [experiment 1, slaughtered at 20-25 h (5-6 h after artificial insemination (AI), group 1-A, n = 4), at 70 h after ovulation (group 1-B, n = 4), on day 11 (group 1-C, n = 4, first day of standing oestrus = day 1) or on day 19 (group 1-D, n = 4)] or 30 h after ovulation [experiment 2, slaughtered at 5-6 h after AI (group 2-A, n = 4) or on day 19 (group 2-D, n = 3)]. The uterine horns were flushed to control for the presence of spermatozoa and neutrophils and/or for recovery of oocytes and/or embryos. Mesometrial uterine samples were plastic embedded and stained. Cryofixed uterine samples were analysed by immunohistochemistry using mAbs to lymphocyte subpopulations and MHC class II molecules. Light microscopy was used to examine surface (SE) and glandular epithelia (GE), and connective tissue layers, both subepithelially (SL) and glandular (GL). In experiment 1, group 1-A, only one sow had spermatozoa in the utero-tubal junction (UTJ). Marked/moderated numbers of neutrophils and spermatozoa were observed in the flushings of two sows. In group 1-B, altogether 23 of 48 oocytes were cleaved. Day 11 (1-C), embryos with small diameter were observed. Day 19 (1-D), no embryos were found but small pieces of foetal membrane were observed in one of the sows. In group 1-A, large numbers of neutrophils were found within the SE and SL but with high individual variation. For T lymphocyte subpopulations, in the SE, most CD2+ cells were found in group 1-A. For both SE and GE in all groups, the number of CD8+ cells was significantly larger than that of CD4+ cells. In experiment 2, group 2-A, no sow had spermatozoa in the UTJ or in the uterine flushings. At day 19, no sow was pregnant. In group 2-A, large numbers of neutrophils were found within the SE and SL but with high individual variation. At day 19, high E2 levels showed a hormonal prooestrous stage but the endometrial neutrophil infiltration normally expected at pro-oestrus was absent. In conclusion, post-ovulatory insemination (about 18 h after ovulation) resulted in impaired spermatozoa transport within the uterus and embryonic degeneration. In sows post-ovulatory inseminated at a later stage (30 h after ovulation), no sow was pregnant. In both experiments, disturbed immune cell patterns were observed in some individuals. 相似文献