Effects Of Appeasing Agent And Toys On The Welfare Level In Weaned Piglets

Weaned stress seriously affected the growth of piglets, and it is closely related to the production benefit, we must take proper measures to alleviate weaned stress. Because the weaned stress is caused by the joint action of various factors, therefore, we should take comprehensive measures to get better effect. We must take measures to conduct nutrition regulation, at the same time, we should also be trying to improve the living environment and weaning piglets welfare, further alleviate the impact of stress on the weaning piglets, thus reduce the loss caused by weaned stress.Experiment 1 studied odor changing patterns in farrowing house and nursery site. We collected odor at 10:00AM in a farrowing house and a nursery site. Odor collection in farrowing house include odor for all farrowing house, odor close to nursing sow venter and odor for defecating ditch. Odor collection in nursery site is odor for all nursery site. Then use Electronic Nose (PEN3) to detect the odor, air intake is 200mL per minute, testing time is 45s, washing time is 100s, and then analyse the data. The result is illustrated blow:(1) Principal component analysis and Linear discriminate analysis between odor in farrowing house and nursery site is done. After principal component analysis, the contribution of two axis is 87.84% and 7.63%, total contribution is 95.47%, higher than 95%. After linear discriminate analysis, there was no overlap between odor in farrowing house and in nursery site.(2) Principal component analysis and Linear discriminate analysis of odor in farrowing house is done. After principal component analysis, the contribution of two axis is 54.44% and 33.04%, total contribution is 87.48%. After linear discriminate analysis, there was no overlap between odor in farrowing house and in defecating ditch, but they both overlap the odor in nursing sow.(3) Principal component analysis and Linear discriminate analysis between odor in sows pen area and corridor. After principal component analysis, the contribution of two axis is 56.95% and 29.98%, total contribution is 86.93%. After linear discriminate analysis, there was overlap between two odors.It was concluded that there were differences between odor in farrowing house and nursery site, but there were no differences between odor inside farrowing house.Experiment 2 studied effect of appeasing agent and toys on weaned piglets. ninety-six piglets weaned at 28 day with similar initial weight (8.60±0.12 kg) were randomly allocated into four groups (control, appeasing agent, toys, appeasing agent + toys) by two factorial design. Each group had 4 replicates of 6 pigs (3 boars and 3 gilts) which come from different mother. Experimental period was 14 d, the tested index included saliva cortisol concentration, skin temperature, respiration rate, skin lesion, behavior and production performance. The result is illustrated blow:(1) Appeasing agent highly significantly reduced saliva cortisol concentration after weaned 7th day(P<0.01). Appeasing agent and toys exists significant interaction for saliva cortisol concentration after weaned 7th day (P<0.05) : if we don't add toys, saliva cortisol concentration in appeasing agent group decreased 16.2% than in the controls; if we do, saliva cortisol concentration decreased 3.0%. After weaned 1st day, appeasing agent significantly increased the skin temperature of the weaned piglets (P<0.05), toys significantly reduced the respiration rate of the weaned piglets (P<0.05). As the extension of weaned time, saliva cortisol concentration in four groups decreased highly significantly (P<0.01). skin temperature in four groups increased in weaned 7th day and then have a trend of decline, respiration rate does not change significantly.(2) After weaned 7th day, skin lesion score in four groups was close to significant difference (P=0.07). Compared with the control group, skin lesion score in the toy group decreased 29.6%, and appeasing agent group decreased 40.0%, toys + appeasing agent group decreased 60.0%. As the extension of weaned time, the skin lesion score in four groups decreased highly significantly (P<0.01).(3) After weaned 14th day, lateral lying behavior in the four groups have significant difference (P<0.05), compared to control group, toys group increased 131.2%, appeasing agent group increased 92.0%, toys+ appeasing agent group increased 36.2%. After weaned 1st day, compared to control group, aggression behavior in the other three groups have a downward trend (P>0.05). After weaned 1st day, pen manipulation behavior in two groups of adding toys have a downward trend (P>0.05). After weaned 7th day, pen manipulation behavior in toy group and appeasing agent group close down obviously, is close to significant difference (P = 0.09).(4) appeasing agent and toys have no significant influence on ADFI,ADG and F/G, and no significant interaction on ADFI,ADG and F/G.It was concluded that appeasing agent can reduce saliva cortisol concentration in weaned piglets, toys can reduce respiration rate of weaned piglets. Appeasing agent and toys both can reduce skin lesion and aggression behavior to a certain extent, toys can reduce pen manipulation behavior in weaned piglets, appeasing agent and toys had no significant effect on production performance for piglets. Anyhow, appease agent and toys can reduce stress and improve the welfare of weaned piglets.