Study On Behaviour Of Sows Before And After Farrowing In Farrowing Crates And Farrowing Pens

Farrowing crates were designed in 1 960s to reduce crushing of the piglets by the sow, now are prevalent in a world since. This system can reduced mortality of piglets from 32%(in pens) to 1 4%(in crates). Later studies show that the crates confines the activities of sows and reduces sow well-being accordingly, though crates improves piglet welfare obviously. rembell committee?stated clearly that an animal should have at least sufficient freedom of movement to be able to turn around, groom itself, get up, lie down and stretch its limbs without difficulty. So, scholars in each country all improvs the design of crate and proposes many kinds of designs such as circle, oval, ellipsoid, turn-around, sloped, etc. They assessed the validity of all designs in a way by observing behaviour of sows. Although many studies have been carried out for study on the effect on the behaviour effected by the designs, there is no report about the orientation preference when sows lay and the frequency of posture transition in pregnancy and lactation periods. Objects of this study are: 1)to compare the effect on behaviour activities of sows in crate and in pen; 2) to compare the change of posture in crate and in pen, and effect on posture transition.Two experiments were carried out to study lying positions, lying posture, orientation and frequency of posture transition of sows before and after parturition in farrowing crates and in farrowing pens.In experiment I, ten Yorkshire sows were observed in farrowing crate for ten weeks. Crate area is l.5x2.3m. Pregnancy pen are loosed one (area is 3.5 x4m) with slight sloped concrete floor.In experiment II, ten Yorkshire sows and ten Landrace sows were observed in pens for ten weeks. Pen is loosed one with concrete floor(area is 3 x3?1 xO.95m) and pig brooder with heater on the top.During observation scan sampling was adopted and the time interval for each observation is five minutes.The results showed that all sows in pen nearly did not lie in feeding area. It took Landrace sows almost half of their time to lie in the middle of lying area. Yorkshire sows spent more than half of their time to lie around lying area. And Yorkshire prefer to lie in the middle of lying area in lactation period. Among them3the amount of time spent on longitudinal lying is more than that on horizontal lying ,but it is not obviours for Yorkshire breed.It was found that the amount of time spent on lateral recumbency is obviously more than that spent on ventral recumbency, and the amount of time spent on lateral recumbency in crate is obviously more than that of in pen. In pen, the amount of time spent on lateral recumbency in lactation period for Landrace sows is obvioursly more than that in pregnancy period, but it is not obvious for Yorkshire sows. In crate, the amount of time spent on lateral recumbency in lactation for Yorkshire is obviously more than that in pregnancy period. The amount of time spent on ventral recumbency increases and that of lateral recumbency reduces as lactation progressed.The results indicate that sows in pen prefer to lying outward, but Landrace lies outward more thanYorkshire, and the amount of time spent on lying outward in pregnancy period is obvious more than that in lactation period.The result shows that the frequency of posture transition in pen is obviously more than that of in crate.Master candidate: Deng HongyuSpecialty:Animal BehaviourSupervisor:Professor Bao Jun...