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21.
Experiments were performed on 11 adult Red Sokoto goats (RSG) with the aim of determining their diurnal temperature fluctuations during the harmattan season. The rectal temperatures (RT) of goats were recorded with a standard clinical thermometer every hour from 06:00 to 19:00 hours. The RT of goats rose gradually from its minimum value of 38.3+/-0.1 degrees C at 06:00 hours and attained its peak value of 39.2+/-0.1 degrees C at 18:00 hours (P < 0.001). Thus, the RT values rose concurrently with increase in ambient temperature. The overall mean RT obtained was 38.7+/-0.1 degrees C. The diurnal fluctuation in the RT of the goats was 1.9+/-0.1 degrees C. There was a highly significant correlation between time of day and RT values (r = 0.947, P < 0.001). The results indicate a diurnal rhythm in the RT of the RSG, which agree with the established pattern of fluctuations in the RT of other breeds of goats. The high diurnal range of 1.9+/-0.1 degrees C confirms that the harmattan season is thermally stressful to the RSG. 相似文献
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Stephen JO White NA McCormick WH Cowles RR Corley KT 《Journal of the American Veterinary Medical Association》2003,223(12):1788-1790
OBJECTIVE: To identify the types of injuries sustained by horses that competed in steeplechase races and determine the prevalence of and risk factors for those injuries. DESIGN: Prospective study. ANIMALS: 2,680 horses that competed in various types of steeplechase races from 1996 through 2000. PROCEDURE: Data regarding races; environment; equipment problems; the number of horses that entered, started, and finished races; the number of riders that fell; and the number of horses that were slowed or stopped by the rider, ran off the course, fell, and sustained injuries or physical abnormalities during races were collected on a standard form by the official veterinarian who attended each meet. Data from all meets were not recorded; however, in recorded meets, data from every race were reported. RESULTS: Data for 197 hurdle, 65 timber, 76 flat, and 8 mixed races were recorded. Nine (3.4/1,000 horses that started in races) horses died or were euthanatized, and 7 of those were associated with catastrophic musculoskeletal injury. Seven fractures were recorded. Four fractures involved forelimbs, 1 involved a hind limb, and 2 involved the cervical portion of the vertebral column. All horses with fractures were euthanatized. Deep or hard course conditions were associated with an increased risk of breakdown injuries. CONCLUSIONS AND CLINICAL RELEVANCE: Successful development and implementation of strategies to prevent injuries and death in horses in steeplechase races depend on a clear understanding of the types and prevalence of injuries involved and risk factors associated with those injuries. 相似文献
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The expression of surface membrane antigens on peripheral blood monocytes (PBM) of cattle of the Boran and N'Dama breeds activated with recombinant cytokines (TNF-alpha and IFN-gamma) and during experimental infection with Trypanosoma congolense was investigated using monoclonal antibodies (MoAbs) and fluorescein-activated cell sorter (FACS). The surface antigens investigated were C3bi receptor, major histocompartibility (MHC) II complex (Ia antigen) and two monocyte/macrophage (Mphi) differentiation antigens. The study revealed that both cytokines caused the enhancement of the expression of all the PBM surface antigens studied. rBolFN-gammaat low concentrations was more efficient in causing the activation of PBM. While the PBM of Boran cattle were more significantly activated to express the C3bi receptor vis-à-vis the Ia antigen than N'Dama cattle, the reverse was the case with the PBM of N'Dama cattle which expressed more Ia antigens than Boran PBM. Similar results were observed during T. congolense infection in the two breeds of cattle. The significantly higher expression of C3bi receptor and correspondingly lower Ia antigen expression by the PBM of Boran cattle, both during trypanosomosis and in vitro may be responsible for the higher rate of erythrocyte phagocytosis, hence the development of more severe anaemia by Boran cattle during trypanosomosis than N'Dama. In addition, the expression of significantly higher numbers of Ia antigen by N'Dama Mphi, hence are more able to process, present and initiate better trypanosome antigen-specific immune response than Boran cattle during infection. These two attributes are known genetic characteristics of trypanotolerance in cattle. 相似文献
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红豆草等草种国家级繁育基地建设初见成效 总被引:1,自引:0,他引:1
介绍了红豆草等草种国家级繁育基地建设项目情况及取得的主要成果,总结了项目建设的主要经验,提出了项目建设的技术措施及建成后的运行管理措施。 相似文献
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不同倍性鸭茅同功酶比较研究 总被引:2,自引:0,他引:2
采用生化遗传学的方法,对我国亚热带地区几个二倍体和四倍体野生鸭茅不同生育期的酯酶,过氧化物酶同功酶进行了比较研究。结果表明,鸭茅二倍体各品系之间,四倍体各品种(系)之间的同源性较高,遗传差异较小,二倍体与四倍体之间,酯酶,过氧经物酶同功酶等都有较大差异。 相似文献
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