Outdoor finishing of intact male pigs of local breed on a high fibre diet: effects on growth, carcass, and some meat quality traits

Thirty male pigs of the Portuguese Alentejano (AL) breed raised outdoors with ad libitum water and feed were used to test the effects of a new high soluble dietary fibre feed on animal performance and carcass traits. From 40 to 130kg body weight, surgically castrated (group C) and intact pigs (groups I and IE) were fed with commercial feeds. From 130kg until slaughter (160kg), groups C and I ate a commercial diet, while group IE was fed the isoproteic and isoenergetic experimental diet, with the incorporation of agro-industrial by-products. Average daily gain (ADG, g/d) was different between groups, with IE pigs presenting a higher ADG than C (691±15 in IE, 649±22 in I, and 610±12 in C pigs, p=0.008). This led to fewer days on trial of IE and I pigs, when compared to C pigs (167±4 in IE, 175±2 in I, and 193±5 in C pigs, p<0.001). Feed conversion ratio was different in all groups, with the lower value in IE and the higher in C group (3.9±0.1 in IE, 4.2±0.1 in I, and 4.6±0.1 in C pigs, p<0.0001). Commercial yield (%) was higher in IE and I groups (48.9±0.3 in IE, 48.8±0.3 in I, and 46.6±05 in C pigs, p<0.001), mainly due to their higher proportion of untrimmed ham. The opposite happened with the fat cuts (%) (24.7±0.4 in IE, 25.0±0.4 in I, and 28.7±0.3 in C pigs, p<0.0001), due to a lower proportion of belly and backfat cuts in IE and I groups (p<0.001 and p=0.002 respectively). ZP fat depth and average backfat thickness were also lower in IE and I groups than in C group (p<0.0001). Overall, these data show that the experimental diet had no effect on growth and carcass traits of intact AL pigs when compared to the ones obtained in intact AL pigs consuming commercial diets. On the other hand, intact AL pigs raised outdoors reached slaughter weigh faster and produced leaner carcasses than castrated ones. Further studies will test the effect of the experimental high fibre feed on pork boar taint and meat quality of intact AL pigs raised outdoors

Effect of a new high fibre feed on blood biochemistry of outdoor finished male local pigs

This work, within the framework of ECO-PIG Project, measured the effects of a high soluble dietary fibre feed on blood biochemistry parameters in outdoor raised Portuguese Alentejano (AL) male pigs (n=30) with access to ad libitum water and feed. Surgically castrated (group C) and intact pigs (groups I and IE) were fed commercial diets from 40 to 130kg body weight. From 130 until 160kg (slaughter), groups C and I were fed commercial feeds while group IE ate the isoproteic and isoenergetic experimental diet, including agro-industrial by-products. Blood samples were collected at 120kg (before the start of the fattening period) and two days before slaughter. Serum levels of total protein, urea (U), glucose, triacylglycerols (TG) and cortisol (COR) were determined. At 120 kg, U levels were different among the groups (3.3±0.2 in IE, 4.0±0.2 in I, and 5.0±0.1 mmol/L in C pigs, p<0.001). At 160 kg, they were different between IE and C groups, again with lower values in intact pigs (3.1±0.2 in IE, 3.4±0.3 in I, and 4.0±0.2 mmol/L in C pigs, p=0.034). These overall lower U levels in intact pigs suggest a more efficient nitrogen use for lean tissue growth than in castrates. TG levels were lower in intact pigs at 160kg (0.30±0.03 in IE, 0.37±0.04 in I, and 0.53±0.04 mmol/L in C pigs, p<0.001). Higher blood TG levels relate with fatter pigs, and C pigs produced fatter carcasses than intact ones (see “The ECO-PIG project: Use of a new high fibre feed for outdoor finishing of intact male local pigs”). Finally, COR levels at 160kg were lower in IE than in I and C pigs (79±13 in IE, 272±38 in I, and 204±22 nmol/L in C pigs, p<0.001). This suggests lower stress levels on the IE group and agrees with the number pigs with of skin injuries related to agonistic interactions observed in the last week of trial (4 in IE, 8 in I and 9 in C pigs). Further studies will test the effect of the experimental feed on pork boar taint and meat quality of intact AL pigs raised outdoors

The ECO-PIG project: Use of a new high fibre feed for outdoor finishing of intact male local pigs

Thirty male pigs of the Portuguese Alentejano (AL) breed raised outdoors with ad libitum water and feed were used to test the effects of a new high soluble dietary fibre feed on animal performance and carcass traits. From 40 to 130kg body weight, surgically castrated (group C) and intact pigs (groups I and IE) were fed with commercial feeds. From 130kg until slaughter (160kg), groups C and I ate a commercial diet, while group IE was fed the isoproteic and isoenergetic experimental diet, with the incorporation of agro-industrial by-products. Average daily gain (ADG, g/d) was different between groups, with IE pigs presenting a higher ADG than C (691±15 in IE, 649±22 in I, and 610±12 in C pigs, p=0.008). This led to fewer days on trial of IE and I pigs, when compared to C pigs (167±4 in IE, 175±2 in I, and 193±5 in C pigs, p<0.001). Feed conversion ratio was different in all groups, with the lower value in IE and the higher in C group (3.9±0.1 in IE, 4.2±0.1 in I, and 4.6±0.1 in C pigs, p<0.0001). Commercial yield (%) was higher in IE and I groups (48.9±0.3 in IE, 48.8±0.3 in I, and 46.6±05 in C pigs, p<0.001), mainly due to their higher proportion of untrimmed ham. The opposite happened with the fat cuts (%) (24.7±0.4 in IE, 25.0±0.4 in I, and 28.7±0.3 in C pigs, p<0.0001), due to a lower proportion of belly and backfat cuts in IE and I groups (p<0.001 and p=0.002 respectively). ZP fat depth and average backfat thickness were also lower in IE and I groups than in C group (p<0.0001). Overall, these data show that the experimental diet had no effect on growth and carcass traits of intact AL pigs when compared to the ones obtained in intact AL pigs consuming commercial diets. On the other hand, intact AL pigs raised outdoors reached slaughter weigh faster and produced leaner carcasses than castrated ones. Further studies will test the effect of the experimental high fibre feed on pork boar taint and meat quality of intact AL pigs raised outdoors