Bernie Peet is president of Pork Chain Consulting Ltd. of Lacombe, Alberta, and editor of Western Hog Journal. His columns will run every second week in the Manitoba Co-operator.
Ialways look forward to the publication of the Kansas State University Swine Day proceedings detailing the results of a range of trials carried out over the previous 12 months. Editors Bob Goodband, Mike Tokach, Steve Dritz and Joel DeRouchey have an international reputation for their outstanding work, especially in the areas of nutrition and feeding. I have selected four of their trials from the 2010 report that I think will be of interest to Canadian producers.
FEED AND WATER STRATEGIES IN THE NURSERY
Two experiments looked at the effects of mat-feeding strategies and different drinker types on pig performance and removal rates. In the first, groups of pigs either received 0.5 kg of pelleted diet on the mats three times daily for six days or were given no feed on mats. In the second trial, pigs were allotted to one of two drinker types, either a dual swinging nipple type or an under-the-fence-line 14-inch pan drinker. In addition, they received 0.73 kg of pelleted feed given three times daily for either three or seven days.
In the first trial, fewer pigs fed on mats died or were removed from pens (5.9 per cent) than control pigs (9.8 per cent), with most removals between treatments occurring within the first 11 days. Because of this difference, overall daily gain and feed efficiency tended to be better for mat-fed pigs compared to the controls because the weight of dead or removed pigs was not recorded or taken into account when calculating growth rate. However, average pig weights on days 0, 11, and 27 were not different between treatments, indicating that the growth advantage was due to the difference in removals rather than increasing weight gain of pigs remaining in the pens. Thus, the researchers concluded, there is a benefit from feeding on mats for six days in reducing the percentage of removed pigs, but no advantages for growth performance.
In the second trial, removal rates were similar for all treatments. Pigs using the swinging drinker nipples showed better growth and feed efficiency than those using the pan drinker and were 0.64 kg heavier at day 32. There was little difference in performance between pigs fed on mats for three or seven days. Overall, the researchers concluded that providing some feed on mats and using a swinging nipple drinker gave the best results.
FEEDER ADJUSTMENT AND FINISHER GROWTH
This trial investigated the effect of feeder adjustment on finishing pig performance and involved three treatments a narrow feeder adjustment (0.50 inch), medium feeder adjustment (0.75 inch), and wide adjustment (1.00 inch). These adjustments resulted in approximately 28, 58, and 75 per cent pan coverage, respectively.
From days 0 to 28, pigs exposed to increasing feeder gap had improved growth rate, with the highest feed intake observed at 1.00 inch. However, from days 28 to 56 and 56 to 89, daily gain was similar among pigs fed from different feeder openings and feed efficiency was best for those fed from the 0.50-inch opening. Overall (days 0 to 89), there was a trend for higher gain with increasing feeder opening. However, pigs fed with a 0.50-inch feeder gap had improved feed efficiency compared to those with a 0.75- or 1.00-inch feeder opening. These results suggest that from 90 to 150 pounds (40.8 to 68 kilograms), maximum daily gain was observed with a feeder setting of 0.75 inch (approximately 58 per cent pan coverage). However, pigs fed from 150 to 270 pounds (68 to 122.5 kg) had better gain and the best feed efficiency at a setting of 0.50 inch (approximately 28 per cent pan coverage). Thus, the researchers conclude, it appears that optimum feeder-gap setting may differ with growth phase.
STOCKING DENSITY AFFECTS FINISHING PIG PERFORMANCE
Finishing pens were stocked with 22, 24, 26, or 28 pigs each, resulting in 8.2, 7.5, 6.9, and 6.4 ft2 per pig, respectively, although no adjustments were made at the pen level to account for space increases because of removed pigs.
Overall, as stocking density increased, daily feed intake and weight gain decreased, but there were no differences in feed efficiency. These performance differences resulted in off-test (day 99) pig weights decreasing as stocking density increased. These data indicate that in this commercial barn, finisher pig feed intake and daily gain improved as the number of pigs in each pen was reduced. However, based on an economic model, income over feed and facility cost per pig placed was numerically optimized when pens were stocked with 24 pigs each, allowing 7.5 ft2 (0.7 m2) of floor space per pig.
MIXING FINISHING PIGS JUST BEFORE MARKETING
The objective of this trial was to determine the effects of mixing late-finishing pigs from one or two barns at different stocking densities on pig performance prior to marketing. Close-to- market-weight pigs from two barns were placed in pens at densities of either 12 or 20 pigs per pen. They were either mixed with pigs from the same barn or the other barn, and there was also a control group with 12 unmixed pigs.
The results showed the number of pigs per pen had a major impact on performance, with pigs stocked at 12 pigs per pen having greater feed intake and daily gain than those stocked at 20 pigs per pen. Overall, there was no difference in performance for non-mixed control pigs and mixed pigs when stocked at a similar density (12 pigs per pen). Although performance was negatively affected immediately after mixing, overall performance of mixed pigs was not different than that of non-mixed pigs. Therefore, given adequate time to adjust to a new environment and establish a new social order, mixing pigs does not appear to affect overall performance, the researchers concluded.