The influence of the length of time after hormonal treatment with [(d-Ala6, Pro9 NEt)-mGnRH+metoclopramide] i.e. Ovopel on barbel Barbus barbus (L.) milt quality and quantity indicators

• Published in: Journal of applied ichthyology Vol. 28; no. 2; pp. 249 - 253
• Main Authors: Cejko, B. I., Kowalski, R. K., Żarski, D., Dryl, K., Targońska, K., Chwaluczyk, R., Kucharczyk, D., Glogowski, J.
• Format: Journal Article
• Language: English
• Published: Oxford, UK Blackwell Publishing Ltd 01.04.2012; Wiley Subscription Services, Inc
• Subjects: Barbus barbus; Freshwater; Poland
• ISSN: 0175-8659; 1439-0426
• DOI: 10.1111/j.1439-0426.2011.01923.x

Summary The study purpose was the analysis of barbel Barbus barbus (L.) milt quality and quantity with regard to the time following stimulation with [(D‐Ala6, Pro9NEt)‐mGnRH+metoclopramide] i.e. Ovopel. Selected parameters such as total volume of milt (TVM, ml), volume of milt per kg of body weight (VOM, ml kg−1 b.w.), sperm concentration (×109 ml−1), total sperm production (TSP, ×109), osmolality (mOsm kg−1) and pH of seminal plasma were determined. Sperm motility was analyzed by the CASA system, i.e. the percentage of sperm motility (MOT, %) and their progressive motility (PRG, %), curvilinear velocity (VCL, μm s−1) and straight line velocity (VSL, μm s−1), amplitude of lateral head displacement (ALH, μm), and beat cross frequency (BCF, Hz). Milt was collected from 12 specimens (N = 12), with the first portion obtained 12 h following treatment with Ovopel (1 granule kg−1 b. w.). Subsequent portions of milt were taken at 24 h intervals, i.e. after 36, 60, 84, 108, and 132 h. The control group (Control, N = 12) was injected with 0.9% NaCl at 0.5 ml kg−1b.w. from which milt was taken 12 h post injection. The highest TVM, VOM and TSP values were recorded 12 h after Ovopel treatment (3.2 ± 0.7 ml, 36.7 ± 10.5 ml kg−1 b.w. and 39.1 ± 9.4 × 109, respectively); lowest values were recorded after 132 h (0.8 ± 0.4 ml, 11.1 ± 6.5 ml kg−1b.w. and 13.7 ± 7.5 × 109, respectively). The highest seminal plasma osmolality values (300.0 ± 42.6 mOsm kg−1) as well as the lowest sperm concentration (12.5 ± 1.5 × 109 ml−1) were observed 12 h after Ovopel treatment. No significant differences in the percentage of sperm motility (MOT) were noted during any of the periods after hormonal stimulation, however, a change in the character of their movement (PRG) was observed. The lack of significant differences (P > 0.05) in VCL and VSL values between 12 h and 60–132 h indicates that the lengthening of time does not lead to a decrease in sperm velocity and, therefore, is not likely to have a negative impact on their quality. The highest ALH (1.9 ± 0.2 μm) and BCF (11.5 ± 1.1 Hz) values were observed when the effect of stimulation was most noticeable, i.e. 12 h after Ovopel treatment. Based on the total milt volume and sperm production, the best time for milt collection from barbel is 12 h post‐hormonal treatment; 84 h post‐hormonal treatment, TVM, VOM, TSP and some CASA parameters decreased, which suggest the same aging process in sperm.