Effects Of Teeth Clipping,Tail Docking And Stocking Density On The Growth Performances,Behavior And Welfare Indicators Of Pigs

The concept of animal welfare began to be accepted by us in recent years.Tail docking,teeth clipping and great stocking density of pigs influenced animal welfare indicators in most intensive pig farms.In order to compare the effects of tail docking and teeth clipping on the behavior and welfare indicators of sows and their piglets,detect the effects of tail docking,teeth clipping and toy on weaned pigs after transfering and mixing and study the effects of stocking density on the behavior and welfare indicators of growing pigs after mixing,I conducted these three experiments;1 Effects of teeth clipping and tail docking on the teat lesions and behavior of sows,the growth performances,behavior and welfare indicators of piglets during lactation periodA total of 302 piglets from 24 litters(12-13 pigs/litter)sow(2-5 parity)were assigned to one of four treatments:teeth clipping and tail docking(TCTD),teeth clipping(TC),tail docking(TD)and sham-processed(Intact).A trained technician performed teeth clipping and tail docking procedures at 3 days of age of piglets.Heart rate(HR)and body surface temperature(BST)of piglets were recorded before and during the procedures.The behaviors of piglets were observed at 1,2,4,5,6,10,17 and 24 days of age,the sows,behaviors were observed at 2,4,8 and 15 days after farrowing during the lactation period.Blood samples were collected from the piglets at 21 days of age to measure the concentrations of serum IgA,IgG and IL-12.Lesions on the body and tail were assessed by inspecting both sides of the body and tail at 2,5,7,10,15 and 21 days of age,and the lesions on the teats of sows were also inspected at-3 2,5,7,9,12,16 and 21 days of farrowing.BW of piglets were recorded at birth and again at weaning.The results showed that HR of piglets during the surgical procedure was greater than that before the procedure in the group TCTD(P<0.01),TC(P<0.01)and TD(P<0,05),but there were no differences in the group Intact(sham-processed).The BST of piglets during the procedure was lower than that before the procedure in the group TCTD(P<0.01)and TC(P<0.01).HR of piglets during the surgical procedure was greater than that before the procedure in the processed piglets.The BST of piglets during the procedure was lower than that before the procedure in the teeth clipping piglets.Processed piglets spent more time on lying-alone(P<0.05)and playing/fighting(P<0.05)than sham-processed piglets.Lesion scores on the body and tail of piglets was unaffected(P>0.05)by teeth clipping and tail docking.ADG and the concentrations of serum IgG,IgA and IL-12 were not different(P>0.05)between groups.On the third day after treatments,sows in the TD group showed more avoidance behaviors(P<0.05)than sows in the TCTD group.No differences(P>0.05)were found on the avoidance behaviors of sows between treatments on the 8th and 14th day after treatments.Lesions scores for the anterior,middle and posterior teats were different(P<0.05)between treatments on d 5 after farrowing,but no differences(P>0.05)were found between treatments during the second and third week after farrowing,2 Effects of teeth clipping,tail docking and toys on the growth,behavior and welfare indicators of weaned pigs after transfering and mixingA total of 262 weaned pigs from 24 litters in the first experiment were used:teeth clipping and tail docking(TCTD,n = 66),teeth clipping(TC,n = 67),tail docking(TD5 n =62)or sham-processed(Intact,n = 67).All the piglets were weaned at 24 d of age by transfering sows from the farrowing crates to a breeding house and leaving the piglets in the farrowing crates.At 30 d of age,weaned pigs in each group were weighed,then mixed into two pens(3.12 m × 3.65 m)in nursery house.One of two pens in each group were equipped with eight toys(13.5 cm × 4 em × 0.8 cm).The behavior of pigs was observed at l,2 and 3 d after mixing.At 3 and 6 d before mixing and at 1,3 and 6 d after mixing,lesions on the body and tail,BST,manure on the body and concentrations of salivary cortisol were determined.The results showed that there were a significant increase of respiratory rate(P<0.01),concentrations of salivary cortisol(P<0.01)and a significant decrease of scores of body lesions and tail lesions(P<0.01)and BST(P<0.01)of pigs after mixing.Toys significantly decreased(P<0.05)respiratory rate of pigs.Clipped piglets spent less(P<0.05)time on negative social behaviors and more time on positive social behaviors(P<0.01)than sham-processed piglets.Docked piglets spent more(P<0.01)time on positive social behaviors than sham-processed piglets.Toys significantly increased(P<0.05)the scores of lesions on the ear and front of body.Docked piglets got greater(P<0.01)scores of lesions on the tail.3 Effects of stocking density on the behavior and welfare indicators of growing pigs after regrouping at different group sizes A total of 243 Landrace x Large White cross barrows were selected and randomly regrouped at one of three stocking densities treatments:1)High density(H),37 pigs in a pen at 0.8 m2/pig,2)Middle density(M),25 pigs in a pen at 1.2 m2/pig,or 3)Low density(L),19 pigs in a pen at 1.6 m2/pig at 135 days of age.There were three pens(3.58 m × 8.17 m)in each group.At 1,3,5,7,9,11,13 and 15 days after regrouping,behavior percentages,lesions on the body and tail,BST,manure on the body and concentrations of salivary cortisol were determined.The results showed that pigs housed at 0.8 m2 per animal had less(P<0.01)scores of body lesions and a higher(P<0.05)proportion of pigs with an abnormally high BST than pigs housed at 1.6 or 1.2 m2/pig.Pigs housed at 0.8 m2 per animal got more(P<0.01)manure on the body and spent more(P<0.01)time on drinking and negative social behaviors than pigs housed at 1.6 m2 per pig.Pigs housed at 1.2 m2 per animal showed more(P<0.05)positive social behaviors than those housed at 1.6 m2.In conclusion,during the lactation period,tail docking and teeth clipping in newborn piglets appeared to produce short-term pain and distress.Leaving teeth and tail intact caused limited and short-term harmful effects on teats of sows but did not influence the growth,behavior and welfare indicators of piglets,which suggests that leaving newborn piglets' teeth and tail intact is feasible during the lactation period.Transfering and mixing after weaning brought stress to weaned pigs,and toys decreased the stress.Also,teeth clipping and tail docking decreased these adverse effects of transfering and mixing after weaning,which suggests that weaned pigs with intact teeth and tail should not mix or regroup after weaning.Mixing or regrouping influenced the behavior and welfare indicators of finishing pigs.The stocking density 1.2 m2/pig(k = 0.067)was optimal considering animal welfare indicators and the building utilization efficiency of finishing pigs.