Objective Sperm Motion Analysis to Assess Dairy Bull Fertility Using Computer‐Aided System – A Review

Abstract

Motility is one of the most important characteristics associated with the fertilizing ability of spermatozoa and is an expression of their viability and structural integrity. Computer-assisted semen analyser (CASA) provides precise and accurate information on different sperm motion characteristics. This article reviews various aspects of computer-aided motility analysis of bull sperm like sample preparation, standardization of instrument settings, importance of various motility parameters evaluated by the system and its impact on basic functional studies of spermatozoa. It gives special emphasis to various aspects of bull sperm motion analysis especially sub-populations of spermatozoa, hyper-activation, motion characteristic in different genetic and age groups, etc. and their utility in predicting the fertility of dairy bulls. The need to fill the gap in research and the necessity of universal standardization of the equipment has been discussed.

Considerations of viscosity in the preliminaries to mammalian fertilisation

“…Modern estimates of sperm motility in mammals, made for the purposes of quality control or fertility prediction, use optical or laser-tracking technology to analyse cell movement within a semen sample diluted in a physiological medium [1][2][3]. Although such an in vitro approach is valuable in both a human and veterinary context, it fails to take account of the varied conditions encountered by a sperm cell during passage along the female tract.…”

Protein biomarkers for male artificial insemination subfertility in bovine spermatozoa

“…The ATP is indispensable for the initiation, regulation, and maintenance of the progressive motility of bull spermatozoa, which is required for successful AI 42, 43, 44, 45, 46. Thus, it is important to conduct an objective investigation of the motility of bull cryopreserved spermatozoa before use in AI with a microscopic image recorder or computer‐associated sperm analyzer 30, 31, 47…”

Proper use and impact of ‘Computer Assisted Semen Analysis’ technique on semen evaluation of farm animals

“…For hyperactivated sperms of men, kinematic definition motility is as follows: VCL ~150 μm s -1 , ALH ~7 μm and LIN ≤0.5 (Mortimer, 1997). In hyperactivated sperms of bulls, kinematic definition motility is VCL ≥70 μm s -1 and ALH ≥7μm (Kathiravan et al, 2011) and in those of boars VCL >97μm s -1 , ALH >3.5 μm, LIN <0.32 and WOB <0.71 (Schmidt and Kamp, 2004).…”

“…Hyperactivated motility is characterized by vigorous, non-linear and non-progressive movement and is occurring just before the acrosomal reaction (Kathiravan et al, 2011). Moreover, it is considered to be important, due to the hypothesis that it could be used for prediction of the in vivo or in vitro fertilisation success (Mortimer, 2000).…”

“…The threshold radius depends on the speed and distance that is expected to go into the interval between two successive shots. The third step involves the combination of coordinates from each sperm individually, trajecting the course at the computer and calculating parametres of motility for each sperm individually and also all of them as a population (Mortimer, 2000;Kathiravan et al, 2011).…”