Effects of three methionine sources in diets on temporal B0AT1 and ASCT2 mRNA expression in different intestinal segments of cobia,Rachycentron canadum     

Yuanfa He  Shuyan Chi  Beiping Tan  Xiaohui Dong  Qihui Yang  Hongyu Liu  Shuang Zhang 《Journal of the World Aquaculture Society》2021,52(1):171-183

A 4‐week feeding trial was conducted using five groups of hybrid grouper (61.15 ± 0.15 g) to explore the potential effects of three methionine (Met) sources. Five isonitrogenous and isolipidic diets were formulated that included a fishmeal (FM) diet; nonsupplemented (NS) diet; or NS diets with the addition of the L‐methionine (L‐Met), DL‐methionine (DL‐Met), or coated Met (Co‐Met) to obtain the same Met level as the FM diet. Fish were randomly distributed into sea cages (30 fish per cage). Weight gain and specific growth rate in the DL‐Met group and FM group were significantly higher than those in all other groups (p < .05). In the proximal and distal intestines, of the 20 gene and time combinations (10 per gene), there were 14 combinations (70%) in which there were no significant differences in gene expression levels between the FM and DL‐Met groups (p > .05). The main reason for the same growth effect between the DL‐Met and FM groups may be attributed to the synchronized absorption at most time points after feeding, which had similar expression patterns of B⁰AT1 and ASCT2 of the proximal and distal intestines between two groups.  相似文献   

Impact of grassland contract policy on soil organic carbon losses from alpine grassland on the Qinghai–Tibetan Plateau          下载免费PDF全文

J. Cao  Y. Gong  E. T. Yeh  N. M. Holden  J. F. Adamowski  R. C. Deo  M. Liu  J. Zhou  J. Zhang  W. Zhang  S. Zhang  D. Sheng  S. Yang  X. Xu  M. Li  Q. Feng 《Soil Use and Management》2017,33(4):663-671

Carbon storage in the soils on the Qinghai–Tibetan Plateau plays a very important role in the global carbon budget. In the 1990s, a policy of contracting collective grasslands to smaller units was implemented, resulting in a change from the traditional collective grassland management to two new management patterns: a multi‐household management pattern (MMP: grassland shared by several households without enclosures) and a single‐household management pattern (SMP: grassland enclosed and used by only one household). In 2016, 50 MMP and 54 SMP winter pastures on the Qinghai–Tibetan Plateau were sampled to assess the differences in soil organic carbon (SOC) between the two management patterns. Results showed that average SOC was significantly greater under MMP than under SMP, with an estimated 0.41 Mg C/ha/yr lost due to SMP following the new grassland contract. Based on the government's grassland policy, four grassland utilization scenarios were developed for both summer and winter pastures. We found that if the grassland were managed under SMP, likely C losses ranged between 0.31 × 10⁷ and 6.15 × 10⁷ Mg C/yr across the Qinghai–Tibetan Plateau relative to MMP, which more closely resembles pre‐1990s grassland management. Previous estimates of C losses have only considered land use change (with cover change) and ignored the impacts driven by land management pattern changes (without cover change). The new data suggest that C losses from the Qinghai–Tibetan Plateau are greater than previously estimated, and therefore that the grassland contract policy should be reviewed and SMP households should be encouraged to reunite into the MMP. These findings have potential implications for land management strategies not only on the Qinghai–Tibetan Plateau but also other grazing regions globally where such practices may exist.  相似文献   

Beaver dams,streamflow complexity,and the distribution of a rare minnow,Lepidomeda copei          下载免费PDF全文

Daniel C. Dauwalter  John D. Walrath 《Ecology of Freshwater Fish》2018,27(2):606-616

Freshwater fishes are threatened globally, and often too little is known about threatened species to effectively guide their conservation. Habitat complexity is linked to fish species diversity and persistence, and degraded streams often lack habitat complexity. Beaver Castor spp., in turn, have been used to restore streams and increase habitat complexity. The northern leatherside chub Lepidomeda copei is a rare, small‐bodied, drift‐feeding minnow that has anecdotally been observed to use complex habitats associated with beaver dams in the western United States. To investigate this anecdote, we conducted fish and habitat surveys, the latter focusing on quantifying habitat complexity, in a sub‐basin of the Upper Snake River Basin in the USA. Complementary generalised linear model and path analyses revealed that northern leatherside chub occurred more often at sites with complex streamflows, and streamflows were more complex when beaver dams were present and pools were deeper. Northern leatherside chubs were also more likely to occur when temperatures were warmer, aquatic macrophytes were abundant and stream channels were narrow and deep. The linkage between chubs, complex streamflows and beaver dams needs to be evaluated more broadly to completely understand its role in the rangewide status of the species. However, it does suggests that increased use of beaver reintroductions and dam analogues for stream restoration could be a boon for the northern leatherside chub, but such efforts should be monitored to determine their effectiveness to help adapt beaver‐based restoration approaches to best benefit the species.  相似文献   

Atypical thymoma in a horse: Diagnostic approach and application of an alternative histological classification system     

T. Pudert  A. Weyrich  F. Geburek  C. Herden  M. Röcken 《Equine Veterinary Education》2021,33(11):e386-e392

Thymoma is a rare condition in horses. This case of a 24-year-old Warmblood gelding that was presented with oedema and signs of vascular congestion of the left forelimb caused by a thoracic mass is described. The diagnostic work-up included blood chemistry, cytology of pleural effusion, ultrasonography, radiography and the visualisation and collection of a tissue sample by thoracoscopy. Finally, post-mortem findings and histopathology revealed thymic epithelial neoplasia with histomorphologic features previously unreported in horses. The unique mixture of spindle-shaped and epithelioid tumour cells in combination with clear features of malignancy suggested the application of the Moran and Suster histological classification system for thymomas in humans (Moran and Suster, 2008, Curr. Treat. Options Oncol., 9, 288), which has not been reported in an equine case before and fits well to the present case.  相似文献   

4个甜樱桃品种在德州的引种表现及设施栽培技术   总被引：1，自引：0，他引：1  

谭延肖  郑现和  徐文胜  韩梅梅 《落叶果树》2020,52(3):33-35

对引入山东德州的4个甜樱桃品种美早、萨米脱、布鲁克斯、拉宾斯进行了日光温室栽培试验,对其性状表现进行了观察。结果表明,4个品种均表现生长良好,适应性强,结果正常,果实品质优良,可以作为德州地区日光温室的栽培品种发展。简述了4个甜樱桃品种在日光温室的栽培技术。  相似文献   

Regulatory role of l-proline in fetal pig growth and intestinal epithelial cell proliferation     

Jing Wang  Bi'e Tan  Jianjun Li  Xiangfeng Kong  Minjie Tan  Guoyao Wu 《动物营养（英文）》2020,6(4):438

l-proline (Pro) is a precursor of ornithine, which is converted into polyamines via ornithine decarboxylase (ODC). Polyamines plays a key role in the proliferation of intestinal epithelial cells. The study investigated the effect of Pro on polyamine metabolism and cell proliferation on porcine enterocytes in vivo and in vitro. Twenty-four Huanjiang mini-pigs were randomly assigned into 1 of 3 groups and fed a basal diet that contained 0.77% alanine (Ala, iso-nitrogenous control), 1% Pro or 1% Pro + 0.0167% α-difluoromethylornithine (DFMO) from d 15 to 70 of gestation. The fetal body weight and number of fetuses per litter were determined, and the small and large intestines were obtained on d 70 ± 1.78 of gestation. The in vitro study was performed in intestinal porcine epithelial (IPEC-J2) cells cultured in Dulbecco''s modified Eagle medium-high glucose (DMEM-H) containing 0 μmol/L Pro, 400 μmol/L Pro, or 400 μmol/L Pro + 10 mmol/L DFMO for 4 d. The results showed that maternal dietary supplementation with 1% Pro increased fetal weight; the protein and DNA concentrations of the fetal small intestine; and mRNA levels for potassium voltage-gated channel, shaker-related subfamily, member 1 (Kv1.1) in the fetal small and large intestines (P < 0.05). Supplementing Pro to either gilts or IPEC-J2 cells increased ODC protein abundances and polyamine concentrations in the fetal intestines and IPEC-J2 cells (P < 0.05). In comparison with the Pro group, the combined administration of Pro and DFMO reduced the expression of ODC protein and spermine concentration in the fetal intestine, as well as the concentrations of putrescine, spermidine and spermine in IPEC-J2 cells (P < 0.05). Meanwhile, the percentage of cells in the S-phase and the mRNA levels of proto-oncogenes c-fos and c-myc were increased in response to Pro supplementation, whereas depletion of cellular polyamines with DFMO increased tumor protein p53 (p53) mRNA levels (P < 0.05). Taken together, dietary supplementation with Pro improved fetal pig growth and intestinal epithelial cell proliferation via enhancing polyamine synthesis.  相似文献   

Digital mapping of soil ecosystem services in Scotland using neural networks and relationship modelling—Part 1: Mapping of soil classes     

Matt J. Aitkenhead  Malcolm C. Coull 《Soil Use and Management》2019,35(2):205-216

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Long-term study of aerobic bacteria of the genital tract in stud dogs.     

L Bjurstr?m  C Linde-Forsberg 《American journal of veterinary research》1992,53(5):670-673

The aerobic bacterial flora of the genital tract was characterized in 15 stud dogs in an 18-month study. The dogs represented 4 breeds and were from 3 kennels. Bacterial samples from the prepuce and semen were collected every month, except in connection with matings, when they were collected weekly (464 samples). The dogs that were included all mated at least once during the study. The mean pregnancy rate, litter size, and pup mortality for the bitches with which they had mated were all within normal limits. The most frequent bacteria isolated from the prepuce and semen were Pasteurella multocida, beta-hemolytic streptococci, and Escherichia coli. There was a tendency for breeds to differ in frequency of the most common bacterial species. Bacterial culture yielded no aerobic growth in 14.2% of the preputial samples and 69.8% of the semen samples. Bacteria were transferred between dog and bitch at mating. In this study of healthy breeding dogs, neither the fertility of the dog nor that of the bitch was affected by the bacteria transferred.  相似文献   

Clinical response of nasal adenocarcinoma to cisplatin chemotherapy in 11 dogs.     

K A Hahn  D W Knapp  R C Richardson  C L Matlock 《Journal of the American Veterinary Medical Association》1992,200(3):355-357

In 11 dogs with nasal adenocarcinoma, IV treatment with 2 to 8 cycles of cisplatin at a dosage of 60 mg/m2 of body surface, given at 3-week intervals, resulted in a survival time of 8 to 128 weeks (mean, 32.7 weeks; median, 20 weeks). Radiography revealed complete remission in 2 dogs and partial remission in 1 dog, for an overall response rate of 27%. Clinical problems such as nasal discharge (n = 11), sneezing (n = 6), and epistaxis (n = 4) resolved in 1 to 2 weeks in all dogs after beginning chemotherapy.  相似文献   

Effect of a supply of raw or extruded rapeseeds on digestion in dairy cows.     

A Ferlay  F Legay  D Bauchart  C Poncet  M Doreau 《Journal of animal science》1992,70(3):915-923

The influence of extruded oilseeds on total tract digestibility and ruminal digestion in dairy cows was studied in three cows fed a hay-concentrate (60.5/39.5; 3.7% fatty acids in diet on DM basis) control diet (C) or the same diet supplemented with raw (R) or extruded (ER) rapeseeds (8.0% fatty acids in diet DM). The experimental design was a 3 x 3 Latin square design. Compared with diet C, diets containing rapeseed decreased ruminal OM digestibility (9.5%, P less than .10) and increased (P less than .05) the proportion of propionate in ruminal fluid VFA. Extrusion had no effect on DM and OM total tract digestibilities and increased (P less than .10) N digestion. Microbial N flow at the duodenum was calculated taking into account solid-adherent bacteria (SAB) and liquid-associated bacteria (LAB). Duodenal flows of total, SAB, and LAB of OM and N did not change with diet. Extrusion of the rapeseeds did not modify (P less than .10) the proportion of bacterial N at the duodenum and had no effect on crude fiber digestibility. This trial demonstrates that rapeseeds in hay-based diets can be fed at levels of up to 14% of the diet without adversely affecting crude fiber digestibility.  相似文献