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[Objectives] This study was conducted to investigate the effect of lipopolysaccharide (LPS) on the gene expression levels of neuromedin B (NMB) and its receptor (NMBR) in the hypothalamic-pituitary-testis (HPT) axis of male rabbits. [Methods] Forty male New Zealand white rabbits were randomly divided into an experimental group injected with LPS and a control group. At 0, 1.5, 3, 6 and 12 h after LPS injection, four rabbits in each group were sacrificed, and the hypothalamus, pituitary and testicular tissues were collected. RT-PCR was carried out to detect the expression of rabbit NMB and NMBR mRNA in the HPT axis. [Results] NMB and NMBR mRNA were expressed in the hypothalamus, pituitary gland and testis of rabbits, and there was a certain time effect, indicating that the NMB/NMBR system is involved in the activities of the hypothalamus-pituitary-testis (HPT) axis. At 1.5 h after LPS stimulation, the expression of NMB mRNA in the hypothalamus increased significantly, and showed an extremely significant difference from the control group (P<0. 01), while the expression of NMBR mRNA in the hypothalamus increased, but was not significantly different from the control group (P > 0. 05). The expression levels of NMB and NMBR mRNA in the pituitary and testis tissues in the HPT axis at different time after the LPS treatment were not significantly different from those in the control group (P > 0. 05). Therefore, LPS stimulation still has a certain effect on the expression of NMB and its receptor mRNA in the HPT axis. [Conclusions]This study is of great significance for the in-depth study on the mechanism of damage caused by immune stress to livestock and poultry reproduction. [ABSTRACT FROM AUTHOR]

Man groves are difficult to map accurately from satellite data by means of parametric classification because of their spectral similarity to other coastal vegetation despite their habitat being inside coastal waters. This study aims to improve the mapping accuracy through incorporation of such spatial knowledge about man groves in the Waitemata Harbor of Auckland, New Zealand, from SPOT data. The spatial knowledge was combined with spectral knowledge in the mapping. Supervised classification was found to map stunted and lush mangroves at an accuracy of, respectively, 46.7 percent and 68.3 percent. These accuracy levels rose, respectively, to 83.3 percent and 96.7 percent after the spatial knowledge was sequentially incorporated into the mapping. A similar accuracy level was achieved from knowledge-based spatial reasoning. If integrated simultaneously with spectral knowledge, spatial knowledge did not improve the accuracy noticeably because of difficulty in gaining quality spectral knowledge. It is concluded that knowledge-based, post-classification processing considerably improves the accuracy of mapping mangroves over parametric classification. [ABSTRACT FROM AUTHOR]