Browsing by Subject "SPERM MOTILITY"

Sort by: Order: Results:

Now showing items 1-2 of 2
  • Iso-Touru, Terhi; Wurmser, Christine; Venhoranta, Heli; Hiltpold, Maya; Savolainen, Tujia; Sironen, Anu; Fischer, Konrad; Flisikowski, Krzysztof; Fries, Ruedi; Vicente-Carrillo, Alejandro; Alvarez-Rodriguez, Manuel; Nagy, Szabolcs; Mutikainen, Mervi; Peippo, Jaana; Taponen, Juhani; Sahana, Goutam; Guldbrandtsen, Bernt; Simonen, Henri; Rodriguez-Martinez, Heriberto; Andersson, Magnus; Pausch, Hubert (2019)
    Background: Cattle populations are highly amenable to the genetic mapping of male reproductive traits because longitudinal data on ejaculate quality and dense microarray-derived genotypes are available for thousands of artificial insemination bulls. Two young Nordic Red bulls delivered sperm with low progressive motility (i.e., asthenospermia) during a semen collection period of more than four months. The bulls were related through a common ancestor on both their paternal and maternal ancestry. Thus, a recessive mode of inheritance of asthenospermia was suspected. Results: Both bulls were genotyped at 54,001 SNPs using the Illumina BovineSNP50 Bead chip. A scan for autozygosity revealed that they were identical by descent for a 2.98Mb segment located on bovine chromosome 25. This haplotype was not found in the homozygous state in 8557 fertile bulls although five homozygous haplotype carriers were expected (P=0.018). Whole genome-sequencing uncovered that both asthenospermic bulls were homozygous for a mutation that disrupts a canonical 5 splice donor site of CCDC189 encoding the coiled-coil domain containing protein 189. Transcription analysis showed that the derived allele activates a cryptic splice site resulting in a frameshift and premature termination of translation. The mutated CCDC189 protein is truncated by more than 40%, thus lacking the flagellar C1a complex subunit C1a-32 that is supposed to modulate the physiological movement of the sperm flagella. The mutant allele occurs at a frequency of 2.5% in Nordic Red cattle. Conclusions; Our study in cattle uncovered that CCDC189 is required for physiological movement of sperm flagella thus enabling active progression of spermatozoa and fertilization. A direct gene test may be implemented to monitor the asthenospermia-associated allele and prevent the birth of homozygous bulls that are infertile. Our results have been integrated in the Online Mendelian Inheritance in Animals (OMIA) database (https://omia.org/OMIA002167/9913/).
  • Kareskoski, Maria; Venhoranta, Heli; Virtala, Anna-Maija; Katila, Terttu (2019)
    Artificial insemination (AI) with cooled stallion semen has increased markedly during the last decades in all countries, but fertility is often lower than when fresh semen or natural mating is used. The objective of this study was to examine field data (1634,cycles 523 Standardbred (SB) mares, 575 Finnhorse (FH) mares, and 90 stallions) using multivariable logistic regression for factors influencing the pregnancy rate (PR) after Al with cooled transported semen from SB and FH stallions. The PR per cycle for the material was 47%: Finnhorses 42% and Standardbreds 53%. When assessed with multivariable logistic regression analyses with a generalized linear mixed model, variables that affected the PR were breed, the number of inseminated estrus cycles, the percentage of progressively motile sperm (PMOT) in the ejaculate/AI dose at the time of shipment, and the number of progressively motile sperm in the Al dose at the time of insemination. In Standardbreds, variables that increased the per cycle PR were the number of Al per estrus cycle (multiple inseminations increasing the probability of pregnancy compared to only one insemination), the number of inseminated cycles, and PMOT in the AI dose at the time of insemination. In Finnhorses, the number of Al per estrus cycle (two and three inseminations increasing the probability of pregnancy compared to only one), the number of spermatozoa in the ejaculate and in the Al dose, and PMOT in the ejaculate/AI dose at the time of shipment increased the per cycle PR. Non-significant factors for the whole material included the type of artificial vagina (open-ended or closed), transport time, place of Al (stud farm or home stable), insemination done by veterinarian or technician, weekday, month, age of the mare (all age classes combined), age of the stallion, ejaculate parameters (sperm concentration, total number of sperm), and insemination dose parameters (volume proportion of seminal plasma, sperm concentration, PMOT, total number of sperm). In conclusion, breed, breeding opportunity in more than one cycle, more than one insemination/estrus, PMOT of the ejaculate/AI dose and the number of progressively motile sperm in the Al dose at the time of insemination are important for the outcome of inseminations with cooled semen. (C) 2018 Elsevier Inc. All rights reserved.