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University of León. University of Groningen. LVQ acrosome integrity assessment of boar sperm cells. Nicolai Petkov 1 , Enrique Alegre 2 Michael Biehl 1 , Lidia Sánchez 2 1 University of Groningen, The Netherlands 2 University of León, Spain. Contents. 1. Introduction. 2. Vectorization.
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University of León University of Groningen LVQ acrosome integrity assessment of boar sperm cells Nicolai Petkov1, Enrique Alegre2 Michael Biehl1, Lidia Sánchez2 1University of Groningen, The Netherlands 2University of León, Spain
Contents 1. Introduction 2. Vectorization 3. Analysis by LVQ 4. Results 5. Conclusions
Quality assessment of semen, e.g. by measuring concentration, motility, morphology, intracellular pattern
Acrosome state Veterinary experts: High fraction of acrosome-reacted cells means low fertilizing capacity Acrosome intact Acrosome reacted
Approach Fertilization potential estimation by Automatic image analysis for Estimation of the fraction of acrosome-intact sperm cells
Cell head segmentation cropping thresholding histogram stretching Opening & closing
Gradient magnitude Acrosome intact Acrosome reacted
Gradient magnitude along head boundary Acrosome intact Acrosome reacted
Labeled data Vectors of gradient magnitudes along the contour Class membership Labeled data P = 152
LVQ1 training • Select randomly example from D • Find nearest prototype vector (winner) • Update winner according to moves prototype towards/away from the actual example
Prototype profiles n = 1 m = 1 intact reacted m = 2 n = 1 i n t a c t reacted
Errors (8-fold cross validation) m and n prototypes of class 1 and 2, resp.
5. Conclusions • Gradient magnitude along the cell head contour is a useful feature vector • LVQ1 with 3 prototypes (2 for class 1) produces (training and test) errors of 0.165 • Veterinary experts call this sufficient for semen quality control in an artificial insemination center