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排序方式: 共有9965条查询结果,搜索用时 31 毫秒
991.
Miguel González-Lozano Daniel Mota-Rojas E. Yadira Velázquez-Armenta Alejandro A. Nava-Ocampo Rafael Hernández-González Marcelino Becerril-Herrera María E. Trujillo-Ortega María Alonso-Spilsbury 《The Canadian veterinary journal. La revue veterinaire canadienne》2009,50(12):1273-1277
Sixty hybrid Yorkshire-Landrace penned sows, 30 with eutocic farrowing and 30 experiencing a dystocic parturition, were studied to evaluate the obstetric and neonatal outcomes to low doses of oxytocin administered at advanced stages of parturition. Animals in each group were randomly subdivided into 2 subgroups: 15 eutocic and 15 dystocic sows received oxytocin 0.083 IU/kg (equivalent to 1 IU/12 kg body weight), administered intramuscularly after the delivery of the 5th piglet; the other 15 eutocic and 15 dystocic sows received saline solution intramuscularly at the same time. Oxytocin decreased the number of intrapartum deaths by approximately 50% (P = 0.002). No piglet was born dead from the saline- and oxytocin-treated eutocic sows. The highest viability score was observed among piglets born to eutocic sows treated with oxytocin. In summary, this dose schedule would help to decrease the number of stillbirths in both eutocic and dystocic farrowing sows. 相似文献
992.
M. Belén García-Rodríguez M. Angeles Ríos Granja C. César Pérez García Jose M. Gonzalo Orden Maria J. Cano Rábano Inmaculada Diez Prieto 《The Canadian veterinary journal. La revue veterinaire canadienne》2009,50(9):933-935
This article describes a complex and not previously reported combination of congenital cardiac defects. Echocardiography showed dilation of right and left chambers, accompanied with patent ductus arteriosus, persistence of the left cranial vena cava, atrial septal defect (ASD), subaortic stenosis, and tricuspid dysplasia. The interatrial wall was examined and the diameter of the ASD was measured by magnetic resonance imaging (MRI). 相似文献
993.
F. Catanese R. Distel J. Arroquy R.M. Rodríguez Iglesias B. Olano M. Arzadun 《Livestock Science》2009,120(1-2):58-65
Experimental evidence suggests that ruminant animals are capable of selecting a nutritionally balanced diet (i.e. a diet appropriate to their metabolic needs) from imbalanced but complementary foods. We tested this hypothesis by offering calves different combinations of the same complementary foods. A 5 × 5 Latin square design was used to assess the effect on diet selection of different combinations (termed as food A and food B) of two complementary foods (alfalfa-grass hay and maize grain) offered in separate feed bunks. In Treatment 1, food A and food B had the same composition, 50.0% hay and 50.0% grain (T50:50). In the rest of the treatments, hay–grain combinations in foods A and B were, respectively: 62.5–37.5% and 37.5–62.5% (T63:37); 75.0–25.0% and 25.0–75.0% (T75:25); 87.5–12.5% and 12.5–87.5% (T88:12); and 100.0–0.0% and 0.0–100.0% (T100:0). Daily intake data were analysed through repeated measures analysis. Crude protein intake was similar across treatments (P = 0.28). An increasing tendency (P = 0.01) in food B intake (the food with more grain content) from T50:50 to T100:0, however, led into a decreasing tendency (P < 0.001) in the protein: energy ratio of the diet across treatments. Grain consumption in treatments T75:25, T88:12 and T100:0 was higher than expected, leading to protein levels in the diet below those required for a balanced diet (predicted vs. observed: 19.38 vs. 16.67, P = 0.004; 20.53 vs. 16.10, P = 0.001; and 20.23 vs. 16.79 g kgMW? 1 d? 1, P = 0.015, for T75:25, T88:12 and T100:0, respectively). Although calves were potentially able to select a balanced diet in all feeding treatments, they failed when offered high grain foods at choice (75% of maize grain or more). Evolved mechanisms to regulate macronutrient intake under natural conditions may fail to adequately operate in artificial environments involving high-energy density foods (e.g. maize grain). 相似文献
994.
Two different herds of Iberian pigs have been studied in the montanera fattening period (from November first to end of December) in the dehesa agrosystem (clear forest of evergreen oaks, Quercus rotundifolia) during two different autumns and winters (2003 and 2004) without any supplementary feed. A direct in situ observation method has been used, with continuous observation of ingestive bites taken by continuously monitored pigs (10 uninterrupted hours, from 08:30 to 18:30) to calculate intake. 95 grazing days have been studied corresponding to different randomly chosen pigs. The obtained results show grass and acorns as the main resources with 56.5 and 43.3% of bites respectively. 14 other resources different from grass and acorns were registered, but only 9 resources (berries, bushes, inorganic rubbish, woods, roots, earth and sand, charcoal and ashes, carrion and straw) were consumed at a frequency ≥ 0.01%. The percentage distribution for daily bites showed no significant difference between years. However daily grazing times were significantly affected by year, and were associated with available drinking water from rain. Lack of water in second montanera forced pigs to return to shelters to drink and, in consequence, reduced daily mean grazing time (from 427 ± 14 min in montanera 1 to 368 ± 8 in montanera 2; P < 0.001) and kernel acorn dry matter intake (from 3.6 ± 0.3 kg in montanera 1 to 3.1 ± 0.1 in montanera 2; P < 0.05); however, it did not significantly influence either daily grass dry matter intake (0.38 ± 0.04 kg in montanera 1 versus 0.49 ± 0.04 kg in montanera 2) or total daily dry matter intake calculated from bite number (4.0 ± 0.3 kg in montanera 1 versus 3.6 ± 0.1 in montanera 2). 相似文献
995.
Stefano Nones Camila Fernandes Lídia Duarte Leonor Cruz Edmundo Sousa 《Plant pathology》2022,71(4):966-979
In Portugal, the oak pinhole borer Platypus cylindrus and its mycobiota have been associated with cork oak (Quercus suber) death, but no knowledge exists regarding the associated bacterial community. However, it is known that some bacteria are important for ambrosia beetle symbiosis and play a role in oak tree health. To explore the bacteria associated with this beetle and its host, with the ultimate goal of highlighting potential roles in oak decline, this study used a culture-dependent approach for strain isolation and phylogenetic identification using 16S rRNA gene sequencing and multilocus sequence analysis (MLSA). The bored galleries of different cork oak trees from a cork stand in Alentejo, together with the body and mycangia of adult beetles, were investigated. The samples revealed a diverse community comprising 500 isolates with 64 distinct types of bacterial colonies. Sixty-eight strains were selected for sequencing and used for phylogenetic analysis, 40 from wood galleries and 28 from beetles. Thirty-two genera of bacteria were identified, 18 of which were described for the first time within oak–beetle interactions. Major taxonomic groups were Actinobacteria in beetles and Enterobacterales in wood galleries. Although specific oak bacterial pathogens were not detected, a group of distinct strains detected in wood galleries, potentially belonging to a new Pectobacteriaceae species, were able to produce mild symptoms on cork oak plantlets. This study reports for the first time the biodiversity of culturable bacteria associated with the Q. suber–P. cylindrus interaction, their relevance to both organisms and the possible contribution to oak decline. 相似文献
996.
Alfaro-Fernández Ana Hernández-Llopis Desamparados Font María Isabel 《European journal of plant pathology / European Foundation for Plant Pathology》2022,164(1):147-147
European Journal of Plant Pathology - 相似文献
997.
998.
Fu Zihao Hong Zijin Wei Junling Liao Yukai You Songlin Wang Yifan Lv Jianjing Feng Huan Kolenčík Marek Chang Xuexiu Qian Yu 《Journal of Soils and Sediments》2022,22(9):2530-2547
Journal of Soils and Sediments - Sediment phosphorus fractionation, adsorption kinetics, and adsorption isotherm characteristics were studied in two rivers, Muyang River and Lengshui River in... 相似文献
999.
Menacherry Sunil Paul M. Kočárek Martin Kacerova Tereza Kotíková Zora Kačer Petr Kodešová Radka 《Journal of Soils and Sediments》2022,22(2):522-535
Journal of Soils and Sediments - Dissipation of pharmaceutical compounds entered into the natural environment is an important process minimizing the adverse effects on the living organisms. The aim... 相似文献
1000.
Ortega Jaime Díaz Sedov Sergey Romero Francisco Jardines Luis Gerardo Martínez Rebolledo Elizabeth Solleiro 《Journal of Soils and Sediments》2022,22(3):942-956
Journal of Soils and Sediments - The objective of this study was to examine the pedogenetic evolution occurring in technic hard materials from an iron mine through the characterization of a... 相似文献