TY - JOUR
T1 - Implications of boar sperm kinematics and rheotaxis for fertility after preservation
AU - Fair, S.
AU - Romero-Aguirregomezcorta, J.
N1 - Publisher Copyright:
© 2019 Elsevier Inc.
PY - 2019/10/1
Y1 - 2019/10/1
N2 - Artificial insemination (AI) is the single most important assisted reproductive technique devised to facilitate the genetic improvement of livestock. In the swine industry, it has broadly replaced natural service over the last number of decades which has been made possible by the high pregnancy rates and litter sizes obtainable with semen extended, up to, and sometimes beyond 5 d. Central to achieving good reproductive performance is the ability of boar studs to monitor semen quality, the basis of which has long been the assessment of sperm motility by subjective and, more recently, by more objective computerised systems. In this review, the literature on the relationship between sperm motility and kinematic parameters and field fertility is summarised. We discuss how this relationship is dependent on factors such as the viscosity of the media and the use of standard operating procedures. Emerging evidence is discussed regarding the importance of sperm rheotaxis and thigmotaxis as long-distance sperm guidance mechanisms, which enable motile functional spermatozoa to avoid the backflow of fluid, mucus and semen from the sow's uterus in the hours post AI, facilitating the establishment of sperm reservoirs in the oviducts. The literature on the use of microfluidics in studying sperm rheotaxis in vitro is also summarised, and we discuss how these systems, when combined with techniques such as lensless microscopy, have the potential to offer more physiological assessments of the swimming patterns of boar spermatozoa. Finally, possible future avenues of further investigation are proposed.
AB - Artificial insemination (AI) is the single most important assisted reproductive technique devised to facilitate the genetic improvement of livestock. In the swine industry, it has broadly replaced natural service over the last number of decades which has been made possible by the high pregnancy rates and litter sizes obtainable with semen extended, up to, and sometimes beyond 5 d. Central to achieving good reproductive performance is the ability of boar studs to monitor semen quality, the basis of which has long been the assessment of sperm motility by subjective and, more recently, by more objective computerised systems. In this review, the literature on the relationship between sperm motility and kinematic parameters and field fertility is summarised. We discuss how this relationship is dependent on factors such as the viscosity of the media and the use of standard operating procedures. Emerging evidence is discussed regarding the importance of sperm rheotaxis and thigmotaxis as long-distance sperm guidance mechanisms, which enable motile functional spermatozoa to avoid the backflow of fluid, mucus and semen from the sow's uterus in the hours post AI, facilitating the establishment of sperm reservoirs in the oviducts. The literature on the use of microfluidics in studying sperm rheotaxis in vitro is also summarised, and we discuss how these systems, when combined with techniques such as lensless microscopy, have the potential to offer more physiological assessments of the swimming patterns of boar spermatozoa. Finally, possible future avenues of further investigation are proposed.
KW - Motility
KW - Pig
KW - Rheotaxis
KW - Semen
KW - Thigmotaxis
UR - http://www.scopus.com/inward/record.url?scp=85066478278&partnerID=8YFLogxK
U2 - 10.1016/j.theriogenology.2019.05.032
DO - 10.1016/j.theriogenology.2019.05.032
M3 - Review article
C2 - 31176491
AN - SCOPUS:85066478278
SN - 0093-691X
VL - 137
SP - 15
EP - 22
JO - Theriogenology
JF - Theriogenology
ER -