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.
“The new varieties offer grain growers the potential to increase energy yields per hectare by 20 to 25 per cent and for pork producers to reduce feed/grain costs on a DE basis,” Campbell says. “The Pork CRC has also invested in a pea-breeding project which has developed and released a new variety called Maki which out-yields the current benchmark varieties by 20 per cent.”
Variability in the nutritional value of feed ingredients is a major challenge for the livestock industry. The technique of Near Infrared Spectrometry (NIRS) has been used for some time to measure protein and various other components of grains. However, the most costly component of grain is its energy value and to date the DE value of grains has not been able to be measured or estimated rapidly with any accuracy.
“Our recent research has measured the variability in the energy value of grains across animal species and developed NIRS calibrations to predict the available energy contents of grains for pigs, ruminants and poultry,” Campbell explains. “The calibrations for pigs are based on wheat, sorghum, barley and triticale. Ileal and fecal DE values varied between grains by nine per cent and 15 per cent respectively. Within grains the variability in fecal and ileal DE values ranged from eight per cent to 15 per cent with the greatest variation occurring in the ileal DE of wheat and barley samples.”
Trials measuring weaner pig performance with the predicted energy content of the diet showed that the differences in DE between grains and within grains were generally reflected in feed efficiency differences of weaner pigs offered diets based on the same grains, Campbell says. However, while sorghums had the highest DE contents they resulted in the worst feed efficiency.
As the pig grows, its protein/ lysine requirement reduces and it is common practice to feed a series of diets over the growing and finishing phase. CRC research has compared the performance and economics of changing the pig’s diet on three occasions between 20 and 100 kg (industry practice), changing the diet weekly or using a single diet over the period that was formulated for pigs averaging 60-65 kg live weight.
“Changing the diet weekly or using a single diet had no effect on overall performance or carcass traits but both strategies reduced feed costs by approximately $3/pig compared to the three-diet phase feeding program,” explains Campbell. “In line with expectations, changing the diet weekly allowed the pig’s changing requirements to be met more closely and enabled overall feed costs to be reduced. However, pigs offered the single diet exhibited poorer growth and feed efficiency in the period to approximately 60 kg but grew faster and were considerably more feed efficient during subsequent development than pigs on the other two treatments.”
The cost savings achieved on the single diet were associated with the lower cost of the diet at the start of the period and the improved feed efficiency supported after 60-65 kg, he adds. “The results suggest the overall cost reduction when a single diet was used was due largely to the pig’s ability to exhibit compensatory growth after a period of nutrient restriction and that this was associated with increased protein deposition,” Campbell comments.
AD LIB VERSUS TWICE-PER-DAY FEEDING
Research with pigs between 25 kg and 105 kg suggests that feeding pigs twice daily over set time periods can result in an improvement in feed efficiency of nine to 10 per cent compared to offering the same diet(s) ad libitum, Campbell notes.
The effects of offering pigs feed ad libitum or for two one-hour periods daily (0900 and 1600 h -phasic) for 49 days on growth performance and carcass fat and muscle contents.
The results (see table, below left) show that there was only a small difference in the feed intake of pigs on each treatment but those on the twice-per-day feeding treatment exhibited a significantly lower feed: gain and contained significantly less fat in the carcass than those offered the diet ad libitum.
“The difference in feed: gain between the two treatments was 10 per cent or some 20 kg/pig, Campbell points out. “The fact that pigs on the phasic feeding treatment were also leaner than their ad libitum-fed counterparts suggests there is a degree of metabolic inefficiency associated with ad libitum feeding.”