基于Gentle AdaBoost算法的牛体检测

针对目标在形状、外观和光照条件发生较大变化时产生的检测率低的问题,以牛体检测为例提出了基于Gentle AdaBoost算法的牛体检测。利用bag of features(BOF)的思想创建特征词典,然后通过词典对牛体目标进行特征提取,最后通过Gentle AdaBoost算法对训练集的BOF特征向量进行训练分类,获得目标对象和场景的分类模型。实验结果表明,该算法训练的检测器在牛体目标存在光照不均匀、形变时均可实现可靠的检测。

Breeding Soundness Examination of Breeding Bull after Infecting Mycoplasma wenyonii

[Objective] The research aimed to study the reproductive health of breed- ing bull after infecting Mycoplasma wenyoniL [Method] The blood and semen quality of breeding bull before and after drug treatment was studied by the methods of blood routine examination and breeding soundness examination （BSE）. [Result] Be- fore the treatment with primaquine phosphate, slight anaemia was seen in diseased bull and a lot of M.wenyonfi were seen on blood smears. The scrotal wall of dis- eased bull swelled, testis was softened, the semen quality was reduced, semen quality was decreased and the proportion of primary and secondary deformed sperms was increased. After drug treatment, M.wenyonfi quickly disappeared from blood and the clinical systems were gradually alleviated, so BSE of breeding bulls after one month was passed. [Conclusion] The research laid the foundation for fur- ther study on the relationship between M.wenyonfi and the reduction of bull＇s repro- ductive functions.

Monoclonal antibody-based ELISA and colloidal gold-based immunochromatographic assay for streptomycin residue detection in milk and swine urine

A protein conjugate of streptomycin （streptomycin-bovine serum albumin （BSA） conjugate） was prepared and used as immunogen to produce monoclonal antibodies （MAb）. One hybridoma secreting anti-streptomycin MAb was obtained and then used to produce MAb. The MAb named 13H5 showed the 50% maximal inhibitory concentra- tion （IC50） value of 4.65 ng/ml and the IC20value of 0.21 ng/ml in phosphate buffered saline （PBS）. At optimum con- ditions, an indirect competitive enzyme-linked immunosorbent assay （ELISA） and a colloidal gold-based immuno- chromatographic assay （CGIA） were developed and applied to detect streptomycin residues in milk and swine urine samples. The developed ELISA showed that the minimum detection limit was 2.0 and 1.9 ng/ml for milk and swine urine samples, respectively, without obvious cross-reactivity to other tested antibiotics except dihydrostreptomycin which gave a 118.32% cross reaction value. Milk and swine urine samples spiked with streptomycin at 10, 50, 100 and 200 ng/rnl were analyzed by the established ELISA. The mean recovery of streptomycin was from 81.9% to 105.5% and from 84.3% to 92.2% for milk and swine urine, respectively. The optimized CGIA showed that the minimum de- tection limit was 20.0 ng/ml for milk and swine urine samples. The results of spiked analysis and specific analysis demonstrate that the CGIA could be applicable for screening milk and swine urine samples for the presence of streptomycin residues on-site. The established ELISA and CGIA allow the rapid, low-cost, and sensitive determination of streptomycin residues in food samples.