Changes in Semen Quality in Estonian Holstein AI Bulls at 3, 5 and 7 years of Age

Abstract

The predictability of semen quality of mature sires from measurements at an early age is not well established. The aim of the present study was to determine age-dependent changes in the quality of bull semen from six Estonian Holstein (EHF) bulls, processed when the sires were 3, 5 and 7 years old. Fertility data such as 60-day non-return to oestrus rates (60d-NRRs) were available for 3-year-old bulls. From each batch, semen straws were analysed immediately after thawing [i.e. post-thaw (PT)] (controls) and after a swim-up (SU) procedure. The analyses comprised subjective and computerized measurements of sperm motility using computer-assisted sperm analysis (CASA) as well as estimations of sperm concentration, morphology and membrane integrity. There was a significant (p < 0.05) increase in the percentage of sperm motility (SU), membrane integrity (PT, SU) and normal tail and acrosome morphology (SU) with an increase in the age of the sires. The percentage of total motile spermatozoa PT measured by CASA correlated between 3- and 7-, and between 5- and 7-year-old bulls (p < 0.05). In addition, the proportion of head abnormalities tended to correlate between all three age groups both PT and after SU (p < 0.1). The sperm parameters correlating with fertility were average path velocity (VAP) (p < 0.001), total motility as measured by CASA (p < 0.01), linearly motile spermatozoa (p < 0.05) and CASA-assessed numbers of motile spermatozoa (p < 0.05), all after SU selection. The results showed that overall semen quality examined at 3 years of age is related to the semen parameters later in bulls' life. Moreover, CASA-assessed motility after SU seems to be a reliable marker for semen quality assessment as it shows correlation not only between the ages, but also to field fertility.

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

“…A similar pattern of motion characteristics (lower progressive motility, VSL, BCF and higher ALH) was observed in case of Jersey ( Bos taurus ) and Kangayam ( Bos indicus ) bulls (Karthikeya 2003; Rengarajan 2004), although the parameter set up varied in the latter studies. Regarding the post‐thaw sperm motion characteristics, progressive motility and velocity were higher in Holstein bulls (Hallap et al. 2006) than that of Jersey breed.…”

“…2002). Analysis of sperm sub‐populations using CASA can be utilized to differentiate the sperm cell composition in different age groups of bulls, which may have some correlation with the differential freezability of semen from young to old animals (Hallap et al. 2006).…”

Fresh and post thaw quality characteristics of Holstein Friesian bull semen maintained at semen production unit Quetta Baluchistan, Pakistan

“…Artificial insemination (AI) is now being widely used nearly in all cattle and buffaloes breeding countries. To achieving higher percentage of conception with artificial insemination, it is essential to improve the techniques of insemination and quality of diluted semen [2,3]. The fertility of spermatozoa, depends not only on the initial quality of semen, but also on subsequently laboratory process of semen dilution, chilling, freezing, storage and transportation, finally thawing for insemination invariably resulted in reduction of the viability and fertilizing capacity of spermatozoa [4].…”

“…The fertility of spermatozoa, depends not only on the initial quality of semen, but also on subsequently laboratory process of semen dilution, chilling, freezing, storage and transportation, finally thawing for insemination invariably resulted in reduction of the viability and fertilizing capacity of spermatozoa [4]. The importance of breeding program is to identify genetically superior breeding bulls and to maximize the number of offspring conceived with frozen semen through artificial insemination (AI) [3]. Short term storage of semen may be satisfactory used for 3 to 4 days to meet day-to-day requirements of AI centers.…”

Changes in Bull Sperm Kinematics after Single Layer Centrifugation

“…Eventually, there is a progressive and irreversible decline in semen quality with age (Hallap et al. ; Bussallou et al. ).…”