Effect of the Pietrain breed used as terminal boar on Post-weaning Multisystemic Wasting Syndrome (PMWS) in the offspring in four PMWS-affected farms     

Nicolas Rose  Alain Abhervé-Guéguen  Gérald Le Diguerher  Eric Eveno  Jean-Pierre Jolly  Philippe Blanchard  Aurélie Oger  André Jestin  François Madec 《Livestock Production Science》2005,95(3):177-186

The aim of this study was to determine the potential risk factors for PMWS at the individual pig level and assess the effect of the Pietrain paternal genetic background of the animals in a cohort study. The survey was set up in four PMWS-affected farms with 2 repetitions (batches) per farm. A representative sample of 60 pigs per batch, stratified according to the paternal genetic background (Pietrain: yes vs. no), was randomly selected after farrowing. The representative cohort was divided into 8 batches and the pigs were individually monitored from birth to slaughter. Survival analysis was used to determine the factors related to the time to PMWS. The litter-cluster effect was taken into account using the marginal Cox model (robust estimation of the covariance matrix) and the gamma shared frailty model which were compared.No protective effect of the Pietrain breed on the time to PMWS and the proportion of affected pigs in the offspring was found in this study. Piglets showing low circovirus type 2 (PCV2) titres at 7 weeks-old with no subsequent seroconversion and piglets from PCV2 negative sows were most likely to be affected by PMWS (HR=7.0 and 2.8, respectively). Active infection of the pregnant dams with parvovirus was related to an increased risk of PMWS in the offspring (HR=2.3). Neck injuries due to poorly performed injections in the dams were associated with an increased risk of PMWS with the marginal model (HR=2.1). Oxytocin injection (dams) during farrowing was protective against PMWS in the offspring (HR=0.6).  相似文献   

Therapeutic effects of recombinant human growth hormone on rat sepsis     

HUANG Ying  WANG Shu-ren  YING Ming-ying  ZHI Mao-hui  LIN Ying 《园艺学报》2003,19(9):1253-1256

AIM:To investigate therapeutic effects of recombinant human growth hormone(rhGH) on rat sepsis and its possible mechanisms.METHODS:Mean arterial pressure (MAP), levels of plasma TNFα, IL-1β and endotoxin, leukocyte count and survival rate within 1 week were determined after E. coli injection among control group, sepsis group and sepsis+rhGH group.RESULTS:(1)rhGH diminished the decrease of MAP, reduced plasma endotoxin and TNFα levels and increased neutrophil ratio in total leukocytes in sepsis rat. rhGH increased survival rate within 1 week on sepsis rat. (2)No changes were found in IL-1β level among the three groups.CONCLUSION:rhGH showed desirable beneficial effects on rat sepsis, which may attribute to: improving circulatory function;maintaining intestinal mucosa barrier, attenuating bacteria/endotoxin translocation and inhibiting the production and release of TNFα.  相似文献   

修剪方式对广玉兰大树移植成活率及生长的影响     

罗贵斌  张建军 《西北农业学报》2016,25(6):875-881

为提高大树移植成活率及探索修剪方式与大树移植成活生长的关系,以20a以上生广玉兰为试材,以全冠移植为对照(CK),分别采用剪去1/3枝叶量的轻度修剪(QX)、剪去2/3枝叶量的中度修剪(ZX)和不留枝叶的截干回缩修剪(JX)3种方式修剪后移植,经过3a连续试验观察,研究不同修剪方式对广玉兰大树移植成活率和生长的影响。结果表明,与CK相比,3种修剪方式极显著提高广玉兰移植后的成活率和新生叶片数、第2年(2013年)和第3年(2014年)的侧梢数、侧梢长度和底径以及第1年(2012年)和第3年(2014年)冠幅生长;与其他2种修剪方式相比,JX显著提高广玉兰移植成活率、第2年(2013年)和第3年(2014年)的侧梢数、顶梢长度、侧梢长度及冠幅生长以及第3年(2014年)的新生叶片数;显著提高第2年(2013年)和第3年(2014年)的侧梢底径。表明截干回缩修剪更有利于广玉兰大树移植的成活和复壮生长。  相似文献   

Prognostic factors in cats with chronic kidney disease     

King JN  Tasker S  Gunn-Moore DA  Strehlau G;BENRIC 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(5):906-916

BACKGROUND: Chronic kidney disease (CKD) is a common cause of morbidity and mortality in cats. HYPOTHESIS: Some baseline variables are associated with shorter survival times in cats with CKD. ANIMALS: Client-owned cats. METHODS: Cats with CKD with initial plasma creatinine concentration > or =2.0 mg/dL and urine specific gravity (USG) < or = 1.025 were recruited into a prospective clinical trial that compared benazepril with a placebo. We describe baseline variables in 190 cats and their influence on renal survival time in the placebo group (95 cats), which was followed for up to 1,097 days. Renal survival time was defined as the time from initiation of therapy to the need for parenteral fluid therapy, euthanasia, or death related to renal failure. RESULTS: Of the 95 cats treated with a placebo, 58 were censored and 37 reached the renal survival end point (died, n = 0; euthanized, n = 17; parenteral fluids, n = 12; parenteral fluids followed by euthanasia, n = 8). Increased plasma creatinine concentration, increased urine protein-to-creatinine ratio (UPC), and increased blood leukocyte count were significantly (P < .01) associated with a shorter renal survival time and were independent risk factors. Increased concentrations of plasma phosphate or urea, and lower blood hemoglobin concentration or hematocrit were significantly (P < .01) associated with a shorter renal survival time and were dependent risk factors, because they also were significantly (P < .01) correlated with plasma creatinine concentration at baseline. CLINICAL IMPORTANCE: Several variables were significantly associated with a shorter renal survival time in cats with CKD.  相似文献   

内蒙古河套灌区节水工程改造效果分析与评估   总被引：6，自引：0，他引：6  

屈忠义  杨晓  黄永江 《农业机械学报》2015,46(4):70-76,112

以内蒙古河套灌区1982—2012年长系列农业净引水量和年降水量资料为基础,运用均值分析、方差分析、相关分析、时间序列分析和生存分析等数理统计学方法,并结合内蒙古河套灌区农业种植发展进程,分析了河套灌区多年农业净引水量变化趋势与影响因素,得出年降水量(超过211.76 mm时,即丰水年)和节水工程改造分别独立地与农业净引水量呈明显负相关关系的结论。运用时间序列法预测了2013、2014和2015年河套灌区的农业净引水量分别为44.5、44.18和43.86亿m3;同时运用生存分析法预测了在灌区现有节水改造规模条件下,河套灌区农业净引水量区间为35~55亿m3,平均为45亿m3。  相似文献   

提高无性系茶苗定植成活率的技术措施   总被引：5，自引：0，他引：5  

李永章 《茶叶通讯》2007,34(3):34-35,38

无性系茶苗定植后成活率低,是当前制约无性系茶园建设的主要因素.本文通过大量调查分析,找出了影响无性系茶苗定植成活率的主要因素,探讨了提高无性系茶苗移栽成活率的措施.  相似文献   

地衣芽孢杆菌降解水产养殖中残余饵料的特性研究   总被引：10，自引：0，他引：10  

谢航  邱宏端  王秀彬  陈冬花 《福建水产》2008,(3)

从土壤及饲料添加剂中筛选获得了一株能较高效降解水产养殖中残余饵料蛋白、淀粉的功能菌,经鉴定为地衣芽孢杆菌.通过研究养殖水体中饲料浓度、pH值、温度等因素对地衣芽孢杆菌降解饲料中蛋白质、淀粉的影响.结果表明,该菌降解饲料中蛋白质、淀粉的适宜条件为:饲料浓度≤5g/L,pH值6～7,温度25～30℃,盐浓度0～1%,溶氧浓度约4mg/L.地衣芽孢杆菌在这种水体生态条件下接种5%,饲料中的蛋白质与淀粉降解率约为60%.  相似文献   

鳙鱼初孵鱼苗的运输试验     

钱培良  陆剑林 《水产养殖》1994,(6):17-18

本文作者在１９９２－１９９３年进行了５次鳊鱼初孵鱼苗（出膜后１－２６小时）的运输试验，都获得成功。鳙鱼初孵鱼苗在运输路程１２０公里、运输时间３－４小时的情况下，运输成活率达９５以上。  相似文献   

Optimal conditions for egg storage, incubation and post-hatching growth for the freshwater turtle, Chelodina rugosa: Science in support of an indigenous enterprise     

Damien A. Fordham  Arthur Georges  Ben Corey 《Aquaculture (Amsterdam, Netherlands)》2007,270(1-4):105-114

Incubation of northern snake-necked turtle (Chelodina rugosa) eggs and subsequent sale of hatchlings for the pet industry has the potential to provide culturally suitable employment for indigenous communities in northern Australia. Developmental arrest in response to egg inundation is unique to C. rugosa. Eggs can be stored under water for up to 10 weeks without appreciable impact on egg or embryo survival, allowing the transport and sale of eggs into niche markets without high levels of mortality, and permitting eggs to accumulate in diapause until there are sufficient numbers to incubate as batches. Eggs that are not inundated or inundated for short periods experience similar survival rates to eggs inundated for lengthy periods. Incubation temperature influences embryo survival and development period in C. rugosa. Embryonic survival is greatest at 26 °C, steadily declining as temperature increases to 32 °C. A similar increase in incubation temperature decreases incubation period by approximately 40 days, however almost half of this variation is attributed to the increase in incubation temperature from 26 to 28 °C. Hatchling growth in C. rugosa is characterized by two phases. There is an initial phase of relatively slow growth under the partial influence of initial egg size and incubation duration, followed by a second phase of relatively rapid growth under the partial influence of water temperature and mass at hatching. Post-hatching survival is negatively correlated with duration of egg inundation and water temperature. Evidence suggests that inundation of C. rugosa eggs for 6 weeks, incubation of embryos at 28 °C and raising hatchlings in 28 °C water will yield the best overall outcomes.  相似文献   

远海梭子蟹人工育苗试验   总被引：1，自引：0，他引：1  

王红勇  王海波  赖秋明 《海洋水产研究》2004,25(3):78-80

试验结果表明,远海梭子蟹在水温28～30℃,盐度32～34条件下,从产卵至孵化需要257h,从第1期蚤状幼体发育变态为仔蟹苗(C1)约需11～13d。整个育苗共投放蚤状幼体46．6万尾,培育出大眼幼体10．11万只,成活率为21．7％,培育成仔蟹苗5．14万只,育苗成活率为11．6％。文中还对胚胎和幼体发育时间与温度和饵料的关系以及幼体培育成活率等进行了讨论。  相似文献