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991.
This study investigated the prevalence of MRSA in samples taken in households, with and without backyard pigs in villages in a rural area of Shandong Province, China. Community‐associated MRSA and livestock‐associated MRSA, belonging to ST59 and ST9, respectively, were identified in both humans and pigs. The genotypic and phenotypic comparison of isolates indicates that bidirectional transmission of MRSA has occurred between humans and pigs in the villages.  相似文献   
992.
就生物科学农业系统中的一元非线性回归模型问题,在相关分析的基础上,按照"残差最小"原则,应用"残差"数据序列,采取关联分析、相对误差、均方差比值、小误差概率等方法进行综合评判,优选模型精度高,与实际相符,且避免了错误应用模型事件发生,为实践应用提供了科学评判依据和手段.  相似文献   
993.
Objectives were to determine associations between percentage pregnancy loss (PPL) in dairy cattle and: (i) pregnancy diagnosis by ultrasonography; (ii) pregnancy diagnosis by serum pregnancy‐specific protein B (PSPB) concentrations, with or without serum progesterone concentrations; and (iii) production and environmental factors. This study included 149 822 pregnancy diagnoses conducted over 13 years in Holstein‐Friesian cows in Hungarian dairy herds. The following were determined: PPL in cows diagnosed pregnant by transrectal ultrasonography 29–42 days after artificial insemination (AI; n = 11 457); PPL in cows diagnosed pregnant by serum PSPB 29–35 days after AI (n = 138 365); and PPL and its association with serum progesterone concentrations, PSPB and production/environmental variables. The definition of PPL was percentage of cows initially diagnosed pregnant based on ultrasonography or PSPB, but not pregnant when examined by transrectal palpation 60 –70 days after AI. The PPL was lower (p < 0.001) in cows following ultrasonographic vs PSPB diagnosis of pregnancy at 29–35 days (8.1 vs 19.3%, respectively), but was higher in cows following ultrasonographic pregnancy diagnosis on 29–35 vs 36–42 days (8.1 vs 7.1%, respectively, P < 0.05). Furthermore, 72.9% of pregnancies with ultrasound‐detected morphological abnormalities resulted in pregnancy loss. As a subset of PSPB data, a fully quantitative PSPB assay was used for 20 430 samples; PPL in cows with a high PSPB concentration (>1.1 ng/ml) was lowest (15.0%), whereas cows with low concentrations of both PSPB and progesterone (0.6–1.1 and <2 ng/ml, respectively) had the highest PPL (76.3%; p < 0.0001). Furthermore, PPL was higher in cows with advanced parity and with high milk production, when ambient temperatures were high, although body condition score (BCS) had no effect on PPL. Finally, there were no significant associations between serum PSPB and environmental temperatures or number of post‐partum uterine treatments.  相似文献   
994.
The consistent failure to isolate bona fide pluripotent cell lines from livestock indicates that the underlying mechanisms of early lineage specification are poorly defined. Unlike other species, the contrivances of segregation have been comprehensively studied in the mouse. In mouse, FGF/MAPK signalling pathway dictates the segregation of hypoblast (primitive endoderm). However, it is not evident whether this mechanism is also conserved in livestock. Here, in this study, we examined the roles of FGF/MAP kinase signalling pathways in porcine parthenogenetic embryos during the early development. Porcine parthenogenetic embryos were cultured in the medium addition with FGFR inhibitor BGJ398 (10 μm ) or DEMOS. Pluripotency‐ and lineage‐related gene expressions in the early porcine embryos were determined. Compared to control, total cell numbers on day 7 were significantly higher (55 ± 5.96 vs 47 ± 1.97, p < 0.05) in embryos cultured in the presence of BGJ398, but had no significant effect on the rate of blastocyst development (47% vs 44%, p > 0.05). Nonetheless, BGJ398 treatment significantly augmented the expression of pluripotency and trophoblast marker genes (SOX2, OCT4, KLF4 and CDX2), but did not significantly change the expression of NANOG and hypoblast marker gene (GATA4). Furthermore, the addition of FGF signalling agonist (FGF2) during the embryo development significantly decreased the expression of pluripotency and trophoblast marker genes (SOX2, NANOG, KLF4 and CDX2), but no significant effect on the expression of OCT4 and GATA4 was observed. Here, we exhibit that inhibition of FGF signalling could improve the quality of the porcine embryo and escalate the chance to capture pluripotency. Besides, it also promotes the trophoblast development of porcine parthenogenetic embryo. In addition, the data suggested that FGF signalling pathway is dispensable for the segregation of hypoblast and epiblast lineages in porcine embryo during the early development.  相似文献   
995.
Predicting male fertility on non‐invasive sperm traits is of big importance to human and animal reproduction strategies. Combining the wide range of parameters monitored by computer‐assisted sperm analysis (CASA) with some molecular traits (e.g. mtDNA content) may help to identify markers of the male fertility. The aim of this study was to characterize variation in the mtDNA copy number in equine sperm and to investigate whether mtDNA content is correlated with quality traits of stallion spermatozoa and the age of the male. Ejaculates collected from 53 fertile stallions were divided into four age groups (3–5, 6–10, 11–14 and >15 years) and were subjected to a complex investigation including conventional analysis, CASA, flow cytometry and mtDNA content (real‐time PCR). The mean (±SD) number of mtDNA copies equalled 14 ± 9 and varied from 3 to 64. Considering the great number of sperm parameters monitored in this study, only few of them were correlated with the mtDNA content: ejaculate volume (a positive correlation), the amplitude of lateral head displacement (ALH; a negative correlation) and the high mitochondrial activity index (a negative correlation). The stallion age was not correlated with the mtDNA copy number. This study provides the first set of data on mtDNA content in equine sperm and confirms phenomena previously described for humans and dog on associations between sperm mtDNA content and selected motility parameters monitored by the CASA. Basing our study on spermatozoa from fertile stallions could however limit the extent of detected associations.  相似文献   
996.
Persistent dorsal displacement of the soft palate (pDDSP) is a relatively rare equine disorder. This case series reports histories and clinical findings in 8 cases of pDDSP, and outcome after treatment of concurrent epiglottic entrapment (n = 3), laryngeal tie‐forward (n = 6) ± laser staphylectomy (n = 2), and/or sectioning of mucosa ventral to the epiglottis and the hyoepiglotticus muscles (n = 2). Four of 6 horses that underwent tie‐forward ± laser staphylectomy had complete resolution of pDDSP and returned to their previous level of work, as did one horse that had a subepiglottic releasing incision. Correction of concurrent epiglottic entrapment in 3 horses with pDDSP did not result in resolution of pDDSP in any case. Previous laryngeal surgery including laryngoplasty and ventriculocordectomy appear to be risk factors for the development of pDDSP.  相似文献   
997.
998.
Studies on genetic variability in Trypanosoma evansi have been limited by a lack of high-resolution techniques. In this study, we have investigated the use of inter-simple sequence repeats (ISSR) and microsatellites in revealing polymorphism among T. evansi isolates. Twelve ISSR primers and five microsatellite loci were used to generate polymorphic bands and alleles, respectively, to investigate the genetic variability among T. evansi isolates from Africa and Asia. Seven of the twelve ISSR primers showed variability between isolates with a total of 71 fragments of which 49(69%) were polymorphic. Microsatellite analysis revealed a total of 60 alleles. On average the ISSR markers revealed a higher genetic diversity (23%) than microsatellites (21.1%). The two techniques showed a strong agreement of r=0.95 for Dice and r=0.91 for Jaccard indices in estimating the genetic distances between isolates. The distance UPGMA tree revealed two major clusters of T. evansi which correlate with the minicircle classification of subtype A and B. The cophenetic correlation coefficient between Dice and Jaccard based matrices were r=0.79 for microsatellites and r=0.73 for ISSR indicating a strong agreement between dendrograms. The results suggest that both ISSR and microsatellites markers are useful in detecting genetic variability within T. evansi.  相似文献   
999.
The macroscopic features of the arterial supply to the reproductive system of the male ostrich was studied in 16 pre-pubertal and eight sexually mature and active birds. The left and right cranial renal arteries arise from the aorta, between the cranial divisions of the kidneys. These vessels supply the cranial divisions of the kidneys, the testes, the epididymides and the cranial segments of the ducti deferentia. Accessory testicular arteries which arise directly from the aorta are present in 45.8% of the specimens. They supply the testes and cranial parts of the ducti deferentia. They are variable in number and origin, and four variants are identified. A cranial ureterodeferential branch originates from the cranial renal artery, supplies the cranial portion of the ductus deferens and ureter, and runs caudally to anastomose with the middle renal artery. The sciatic artery arises laterally from the aorta, just caudal to the acetabulum, and gives rise, ventrally, to a common trunk, the common renal artery, which divides into the middle and caudal renal arteries. The middle renal artery gives rise to the middle ureterodeferential branch which supplies the middle part of the ductus deferens and ureter. A few centimetres caudal to the kidney, the aorta terminates in three branches, namely, the left and right internal iliac arteries and the median caudal artery. The internal iliac artery divides into the lateral caudal artery and the pudendal artery; the latter gives off caudal ureterodeferential branches that supply the caudal segments of the ductus deferens and ureter. In addition, the pudendal artery gives off vessels that supply the cloaca, some of which continue to the base of the phallus, where they form an arterial network. In conclusion, the pattern of the blood supply to the reproductive organs of the male ostrich is, in general, similar to that of the domestic fowl and pigeon, although there are a few highlighted distinctive features.  相似文献   
1000.
The efficacy of decoquinate against Eimeria infections in broiler chickens was evaluated using two drug sensitive laboratory strains of Eimeria tenella and 20 field isolates of Eimeria spp. collected from farms in China where various anticoccidials (including maduramicin) had been used. Decoquinate (20-40 ppm in feed) and maduramicin (5 ppm) were efficacious against E. tenella laboratory strains, but decoquinate more so than maduramicin. Body weight gains of E. tenella infected chickens were significantly improved, and caecal lesions were prevented, by feeding either decoquinate or maduramicin. Decoquinate also prevented oocyst production, but maduramicin did not. Most (18/20) Eimeria field isolates were resistant to maduramicin, judged by oocyst production; decoquinate at > or =20 ppm completely controlled all 20 field isolates. Decoquinate has potential value as a broiler anticoccidial in China and other countries where it has not been previously used.  相似文献   
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