|Kirby, J - UNIVERSITY OF ARKANSAS|
|Froman, D - OREGON STATE UNIVERSITY|
|Harry, D - NICHOLAS TURKEY FARM|
|Darden, J - HYBRID INC.|
|Marini, P - NICHOLAS TURKEY FARM|
|Rhoads, M - UNIVERSITY OF ARKANSAS|
Submitted to: Poultry Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 30, 2000
Publication Date: December 1, 2000
Citation: King, L.M., Kirby, J.D., Froman, D.P., Sonstegard, T.S., Harry, D.E., Darden, J.R., Marini, P.J., Rhoads, M.L., Donoghue, A.M. 2000. Efficacy of sperm mobility assessment in commercial flocks and the relationship of sperm mobility and insemination dose on fertility in turkeys. Poultry Science. Interpretive Summary: Our objective was to evaluate the Sperm Mobility Test on commercial farms. In research flocks, the test, has shown differences in sperm mobility among males and is predictive of fertility. Semen from each of 405 breeder toms (11 strains) was evaluated in duplicate (n= 285) or in triplicate (n = 120). Sperm mobility was normally-distributed among all toms tested, except for one strain. There were no correlations between sperm mobility, semen volume, or sperm concentration in any of the breeder toms tested. Because the sperm mobility indexes for toms evaluated in these field trials were higher than observed in research flocks, the Sperm Mobility Test was modified to increase the separation between high or low sperm mobility phenotypes. The concentration of Accudenz was increased from 2% to 6% (w/vol) to optimize the test. To determine the effects of sperm mobility and insemination dose on duration of fertility, hens were inseminated twice ebefore the onset of lay with sperm from toms classified as High, Average, or Low mobility in concentrations of 25 to 400 million sperm/AI dose, and egg fertility was evaluated for 5 weeks. High mobility sperm maintained higher fertility (P < 0.05) at all insemination doses compared to Low mobility sperm. Toms with high mobility sperm also sired more poults (P < 0.05) in sperm competition studies using 25% High mobility sperm + 75% Low mobility sperm/AI dose. These results demonstrate that the Sperm Mobility Test can be used for on-farm evaluation of semen quality of toms in commercial flocks.
Technical Abstract: A study was conducted to evaluate the integrity of turkey sperm membranes subjected to various hypo-osmotic conditions, and to develop a test to determine the% viable sperm capable of withstanding hypo-osmotic stress after in vitro storage. For Trial I, sperm were subjected to varying osmotic solutions by suspension in PBS, 297-19 mosm/kg H2O and stained to assess membrane integrity with Calcein AM and propidium iodide. Viable sperm, as determined by flow cytometric analysis was not different from 100% PBS, to 20% PBS. Fewer viable sperm, however, were detected in 0% PBS (P<0.05). Swollen tails observed for viable sperm were 0, 4.5, 6.5, 24.3, 50.5 and 100% for 100, 80, 60, 40, 20 and 0% PBS, respectively. Semen was also evaluated fresh or after 24 h in vitro storage at 5 C in PBS or H2O (Trial II). The% viable sperm was not different for fresh or in vitro stored sperm in PBS. For sperm stored 24 h in vitro, viable sperm was lower in H20 than in PBS (P<0.05). Subjecting in vitro stored sperm to hypo-osmotic stress before fluorescent staining resulted in detection of labile sperm not accounted for by staining alone indicating that the turkey sperm membrane is more susceptible to damage after cold storage.