title: Effect of mating frequency on sow reproductive performance under field conditions and natural mating in large outdoor production units.
abstract: The effect of mating frequency on fertility and litter size of sows, kept in outdoor production systems was investigated. Sows that were mated once or twice during a single oestrus were included in the study to compare the effect of number of matings on farrowing rate and litter size. Natural mating was used during the study period. Four groups of sows of parity two or more were either mated once 28-30 h after the onset of oestrus or were mated 28-30 h after the onset of oestrus and again 24 h later. The farrowing rate did not differ significantly between single- and double-mated sows, although a noticeable but non-significant depression in farrowing rate was evident between the groups of single-mated and double-mated animals. With the exception of total-born litter size (p > 0.05), the total number born and number of live-born piglets per litter were significantly (p < 0.05) lower in the group of sows that received only one mating compared with the double-mated animals. The implication of these results is that the double mating by natural service of sows kept in an outdoor production systems may improve litter size.
authors.affiliation: Bilkei Consulting, Dübendorf and Alföld, Hungary.
authors.forename: C M
authors.initials: CM
authors.lastname: Waller
authors.forename: G
authors.initials: G
authors.lastname: Bilkei
mesh_terms: D000818:Animals; D003307:Copulation / Q000502:physiology*; D005260:Female; D005298:Fertility; D008098:Litter Size; D011247:Pregnancy; D012098:Reproduction / Q000502:physiology*; D013552:Swine / Q000502:physiology*; D013997:Time Factors