title: Effect of number of motile sperms inseminated on reproductive performance of rabbit does.
abstract: The relationship between the number of motile sperms inseminated and fertility rate and litter size at birth in rabbits was investigated. A total of 651 artificial inseminations on multiparous rabbit does in different physiological states (lactating or not; sexually receptive or not) were inseminated with a number of motile cells/dose varying from about 1-20 x 10(6). The statistical model computed the following traits: maximum expected value (a), rate of approach to this value (b) and number of motile spermatozoa/dose needed to obtain threshold level (95% of the maximum). The physiological condition of the doe affected the reproductive performance. The sexual receptivity had significant effect during lactation: non-receptive does had the lowest fertility (a: 43.70%; P < 0.05) while no significant differences were found in non-lactating ones (73.80 vs. 89.11%). Also the rate of approach to this maximum was different: non-receptive does showed a higher dependence on spermatozoa number than receptive females (b: 0.69 and 0.58, respectively, in lactating and non-lactating does) and consequently more spermatozoa (13.1 and 11.1 x 10(6) motile/dose) were needed to reach the threshold value. The physiological state of the does did not affect litter size and only 4.1 x 10(6) of motile spermatozoa/dose are needed to reach the threshold value.
authors.affiliation: Dipartimento di Scienze Zootecniche, Universita di Perugia, Italy. zooted@unipg.it
authors.forename: C
authors.initials: C
authors.lastname: Castellini
authors.forename: P
authors.initials: P
authors.lastname: Lattaioli
mesh_terms: D000818:Animals; D005260:Female; D007315:Insemination, Artificial; D008098:Litter Size; D008297:Male; D008954:Models, Biological; D015233:Models, Statistical; D011247:Pregnancy; D011817:Rabbits; D012098:Reproduction / Q000502:physiology*; D012726:Sexual Behavior, Animal; D013081:Sperm Motility; D013094:Spermatozoa / Q000502:physiology*