PSVII-17 The relationship of biochemistry of seminal plasma, ejaculate volume and sperm concentration in horses

Abstract

Abstract The aim of the work was to study the relationship between biochemistry of seminal plasma with the ejaculate volume and the concentration of spermatozoa. Ejaculates from 35 stallions aged 5 to 15 were collected during the breeding season (February–May). The concentration of calcium (Ca), phosphate (P), potassium (K), magnesium (Mg), selenium (Se), zinc (Zn) and lithium (Li) in seminal plasma were determined by atomic emission and mass spectrometry (AES-ICP and MS-ICP) using an mass spectrometer Elan 9000 (Perkin Elmer, USA) and an atomic emission spectrometer Optima 2000V (Perkin Elmer,USA). The concentration of glucose, phospholipids, aspartate-amino-transferase (AST) and alkaline phosphatase (AIP) was determined by ChemWell 2902V analyzer (Awareness Technology, USA). The significance of differences between the indices was determined using Student’s t-test, the differences at P ≤ 0.05 were considered statistically significant. A significant negative correlation between the volume of ejaculate and concentration of Se (r = -0.42; P = 0.01), P (r =-0.39; P = 0.001), AIP (r = -0.48; P = 0.01), Zn (r = -0.40; P = 0.01), Li (r = -0.39; P = 0.02), phospholipids (= -0.52; P = 0.03) in seminal plasma was established. A correlation between the concentration of sperm and the concentration of P (r = 0.71; P = 0.01), Se (r = 0.39; P = 0.02), Li (r = 0.33; P = 0.05), AIP (r = 0.81; P = 0.001) in seminal plasma was established. Also a negative correlation between the concentration of sperm and glucose (r = -0.62; P = 0.01) was found. We assumed that selenium, zinc, phosphorus, lithium, phospholipids and AIP in seminal plasma have an epididymal origin and do not depend on the secretion of the accessory sex glands. Glucose enters the ejaculate with the secrets of the accessory sex glands. Authors acknowledge financial support from Russian Science Foundation, Grant No: 17-16-01109, development program of Bioresource collections “Cryobank of genetic recourses the All-Russian Research Institute for Horse Breeding.”