Behavioural adaptation in the domestic horse: potential role of apparently abnormal responses including stereotypic behaviour     

Jonathan J. Cooper  Melissa J. Albentosa 《Livestock Production Science》2005,92(2):177-182

Classically, biologists have considered adaptation of behavioural characteristics in terms of long-term functional benefits to the individual, such as survival or reproductive fitness. In captive species, including the domestic horse, this level of explanation is limited, as for the most part, horses are housed in conditions that differ markedly from those in which they evolved. In addition, an individual horse's reproductive fitness is largely determined by man rather than its own behavioural strategies. Perhaps for reasons of this kind, explanations of behavioural adaptation to environmental challenges by domestic animals, including the capacity to learn new responses to these challenges, tend to concentrate on the proximate causes of behaviour. However, understanding the original function of these adaptive responses can help us explain why animals perform apparently novel or functionless activities in certain housing conditions and may help us to appreciate what the animal welfare implications might be. This paper reviews the behavioural adaptation of the domestic horse to captivity and discusses how apparently abnormal behaviour may not only provide a useful practical indicator of specific environmental deficiencies but may also serve the animal as an adaptive response to these deficiencies in an “abnormal” environment.  相似文献   

Intracytoplasmic Glutathione Levels in Heifer Oocytes Cultured in different Maturation Media and its Effect on Embryo Development     

MJ Mertens  M López-Bejar  M-T Paramio 《Reproduction in domestic animals》2005,40(2):126-130

The present study was carried out to study the effect of different maturation media on embryo development of heifer oocytes and on their glutathione (GSH) synthesis during in vitro maturation (IVM). Immature heifer oocytes were matured in parallel in one of four maturation media: (i) Tissue Culture Medium (TCM)-199 supplemented with 10 ng/ml of epidermal growth factor (EGF); (i) TCM-199 supplemented with 10 ng/ml of EGF plus 1 microg/ml of FSH; (iii) TCM-199 supplemented with 10% of foetal bovine serum (FBS) and (iv) TCM-199 supplemented with 10% of FBS plus 1 microg/ml of FSH. Cow oocytes were used as control and were matured in TCM-199 supplemented with 10 ng/ml of EGF. No differences were observed in blastocyst rate among the different heifer oocyte groups (8.8, 7.5. 8.4 and 6.8%, respectively) however, the percentage of blastocysts obtained from cow oocytes was significantly higher (30%; p < 0.01) than those obtained from heifer oocytes. De novo GSH synthesis during oocyte maturation of heifer and cow oocytes was detected. No significant differences in intracytoplasmic GSH levels were observed among the experimental heifer oocyte groups or between heifer and cow oocytes both before and after IVM. In conclusion, the blastocyst yield obtained from heifer oocytes was lower than that from cow oocytes and this fact could not be explained by significant differences in intracytoplasmic GSH contents of oocytes before or after IVM.  相似文献   

恩拉霉素的研究进展   总被引：4，自引：0，他引：4  

周岷江  严玉宝  胡娟  余华  叶建强  谢晶  汤华钊 《中国兽药杂志》2007,41(12):42-44

概述了恩拉霉素的理化特性、药效学、毒理学和临床应用研究进展,展望了今后恩拉霉素的研究方向.  相似文献   

Temperature and surface-ocean water balance of the mid-holocene tropical western pacific     

MK Gagan  LK Ayliffe  D Hopley  JA Cali  GE Mortimer  J Chappell  MT McCulloch  MJ Head 《Science (New York, N.Y.)》1998,279(5353):1014-1018

Skeletal Sr/Ca and 18O/16O ratios in corals from the Great Barrier Reef, Australia, indicate that the tropical ocean surface approximately 5350 years ago was 1 degrees C warmer and enriched in 18O by 0.5 per mil relative to modern seawater. The results suggest that the temperature increase enhanced the evaporative enrichment of 18O in seawater. Transport of part of the additional atmospheric water vapor to extratropical latitudes may have sustained the 18O/16O anomaly. The reduced glacial-Holocene shift in seawater 18O/16O ratio produced by the mid-Holocene 18O enrichment may help to reconcile the different temperature histories for the last deglaciation given by coral Sr/Ca thermometry and foraminiferal oxygen-isotope records.  相似文献   

Formation of molecular chlorine from the photolysis of ozone and aqueous sea-salt particles     

KW Oum  MJ Lakin  DO DeHaan  T Brauers  BJ Finlayson-Pitts 《Science (New York, N.Y.)》1998,279(5347):74-77

Halogen atoms from the reactions of sea-salt particles may play a significant role in the marine boundary layer. Reactions of sodium chloride, the major component of sea-salt particles, with nitrogen oxides generate chlorine atom precursors. However, recent studies suggest there is an additional source of chlorine in the marine troposphere. This study shows that molecular chlorine is generated from the photolysis of ozone in the presence of sea-salt particles above their deliquescence point; this process may also occur in the ocean surface layer. Given the global distribution of ozone, this process may provide a global source of chlorine.  相似文献   

Mechanism of the Zonal Displacements of the Pacific Warm Pool: Implications for ENSO   总被引：7，自引：0，他引：7  

J Picaut  M Ioualalen  C Menkes  T Delcroix  MJ McPhaden 《Science (New York, N.Y.)》1996,274(5292):1486-1489

The western equatorial Pacific warm pool is subject to strong east-west migrations on interannual time scales in phase with the Southern Oscillation Index. The dominance of surface zonal advection in this migration is demonstrated with four different current data sets and three ocean models. The eastward advection of warm and less saline water from the western Pacific together with the westward advection of cold and more saline water from the central-eastern Pacific induces a convergence of water masses at the eastern edge of the warm pool and a well-defined salinity front. The location of this convergence is zonally displaced in association with El Nino-La Nina wind-driven surface current variations. These advective processes and water-mass convergences have significant implications for understanding and simulating coupled ocean-atmosphere interactions associated with El Nino-Southern Oscillation (ENSO).  相似文献   

Differential Rotation and Dynamics of the Solar Interior     

MJ Thompson  J Toomre  ER Anderson  HM Antia  G Berthomieu  D Burtonclay  SM Chitre  J Christensen-Dalsgaard  T Corbard  M DeRosa  CR Genovese  DO Gough  DA Haber  JW Harvey  F Hill  R Howe  SG Korzennik  AG Kosovichev  JW Leibacher  FP Pijpers  J Provost  EJ Rhodes  J Schou  T Sekii  PB Stark  PR Wilson 《Science (New York, N.Y.)》1996,272(5266):1300-1305

Splitting of the sun's global oscillation frequencies by large-scale flows can be used to investigate how rotation varies with radius and latitude within the solar interior. The nearly uninterrupted observations by the Global Oscillation Network Group (GONG) yield oscillation power spectra with high duty cycles and high signal-to-noise ratios. Frequency splittings derived from GONG observations confirm that the variation of rotation rate with latitude seen at the surface carries through much of the convection zone, at the base of which is an adjustment layer leading to latitudinally independent rotation at greater depths. A distinctive shear layer just below the surface is discernible at low to mid-latitudes.  相似文献   

14 EVALUATION OF BACTERIAL CONTAMINATION AFTER UNCOMPLICATED EQUINE CASTRATIONS.     

MJ  Schoonover  HD Moll  CL Crowson  HW Jann 《Veterinary surgery : VS》2003,32(6):601-602

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Reduction of Pesticide Residues on Produce by Rinsing     

Krol WJ  Arsenault TL  Pylypiw HM  Incorvia Mattina MJ 《Journal of agricultural and food chemistry》2000,48(11):5788

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Hypovitaminosis A in pigs     

MJ CARRIGAN  JRW GLASTONBURY  JV EVERS 《Australian veterinary journal》1988,65(5):158-160

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