title: Effects of (artificial) boar stimuli on uterine activity in estrous sows.
abstract: This study aims to examine influences of specific boar stimuli on uterine activity in estrous sows, by comparing uterine activity in presence of a mature teaser boar and a robot boar with variable stimuli. Nineteen multiparous, cyclic, commercial crossbred sows were used. Intra-luminal uterine pressure was measured using a non-surgical method for 45 min before applying one of four treatments in combination with a back-pressure-test (BPT): (1) robot with olfactory and auditory stimuli (R+O+A) (n=16), (2) robot with auditory stimuli (R+A) (n=16), (3) robot without additional stimuli (R) (n=16), (4) a mature boar (boar) (n=15). After treatment, measurements continued for 30 min. For each measurement, frequency, mean amplitude and mean duration of uterine contractions were determined. Spontaneous frequency of uterine contractions was 18.6+/-0.7 h(-1) on average and did not differ between treatments. Frequency of contractions increased significantly for the boar (+5.6+/-1.3 h(-1); P<0.01), R+O+A (+3.9+/-1.3; P<0.01) and R+A (+2.6+/-1.3; P<0.05). The effect of boar presence on frequency of contractions was greater than the effect of R (P<0.05). Amplitude and duration of contractions were not affected by treatment. The change in frequency was dependent on spontaneous frequency (P<0.01). In conclusion, the higher the level of boar stimuli, the greater the increase in frequency of uterine contractions. The results indicate that the used combinations of artificial boar stimuli do not mimic a 'whole' boar. It is unclear which boar stimuli stimulate maximal uterine activity during estrus.
authors.affiliation: Adaptation Physiology, Animal Sciences Group, Wageningen University, P.O. Box 338, 6700 AH Wageningen, The Netherlands. rosemarijn.gerritsen@wur.nl
authors.forename: R
authors.initials: R
authors.lastname: Gerritsen
authors.forename: P
authors.initials: P
authors.lastname: Langendijk
authors.forename: N M
authors.initials: NM
authors.lastname: Soede
authors.forename: B
authors.initials: B
authors.lastname: Kemp
mesh_terms: D000161:Acoustic Stimulation; D000818:Animals; D004971:Estrus; D005260:Female; D008297:Male; D010812:Physical Stimulation; D011312:Pressure; D012726:Sexual Behavior, Animal; D012903:Smell; D013552:Swine / Q000502:physiology*; D014590:Uterine Contraction; D014599:Uterus / Q000502:physiology*