Feeding lightweight (under 10 lb.) weaned pigs supplemental liquid milk replacer can ease their transition into the nursery, according to researchers at the University of Missouri.

Small weaned pigs have the ability to gain 1.6 lb. in the first three days after weaning when they are offered liquid milk replacer along with dry feed. In contrast, pigs offered only a dry diet lost 1/3 lb. during that period, reports Missouri swine nutritionist Gary Allee.

A total of 264 pigs, weaned at 17 days (plus or minus two days) were used in four different experiments. They represented the bottom 15% of four weaning groups. A dry diet was provided to all pigs, ad libitum, in two phases.

The phase I diet, fed for two weeks, contained 3.5% spray-dried plasma and at least 15% lactose. The phase II diet, fed to the completion of the study, contained 2.5% blood cells and at least 7.5% lactose. Spray-dried plasma and blood cells are different feed additives both derived from whole blood.

The milk replacer (Merrick's Litter Life) was supplied ad libitum to the pigs through an in-line system. A hydro pump was attached to a central, 30-gal. tank and the milk was pumped to bowls equipped with nipples.

In experiment 1 (48 pigs averaging 9.5 lb.) and experiment 2 (72 pigs averaging 9.3 lb.), the pigs were randomly assigned to one of four treatments. Pigs were assigned two/pen in experiment 1 and three/pen in experiment 2. Four treatments were offered, including dry diet only and the dry diet supplemented with milk replacer for 3, 5 or 7 days, respectively. The pigs were weighed and dry feed consumption recorded on days 0, 3, 5, 7, 10 and 29.

In the third experiment, 72 pigs weighing 9.9 lb. were penned three/pen. Weight and dry feed consumption were recorded on days 0, 3, 5, 7, 10 and 29.

In the fourth experiment, 72 pigs (9.6 lb.) were given only the first three treatments (no milk replacer, three days of milk replacer and five days of milk replacer) and were penned four/ pen. Weight and dry feed consumption were recorded on days 0, 3, 5, 7 and 21.

The results show no significant difference in dry feed intake for the four experiments. In experiment 1, the pigs given milk replacer for either five or seven days were heavier at day 10 than pigs not fed any milk replacer. Pigs fed the milk replacer for three days had an intermediate weight. The researchers note that the weight difference was lost, since there was no significant effect of the milk replacer on pig weights on day 29.

In experiment 2, pigs given milk replacer for five or seven days were heavier throughout the study. They weighed more than the three-day milk replacer group and the pigs fed no milk replacer. The researchers note that after day 5, there was no significant difference in weights between the pigs fed no milk replacer and the pigs receiving the three-day treatment.

In experiment 3, the pigs fed no milk replacer were lighter than all the other groups for the entire study. Pigs given milk replacer for either three or seven days consumed more dry feed than the pigs given no milk replacer and the five-day treatment group.

In experiment 4, pigs fed no milk replacer were lighter and total dry feed intake for the 21-day study was not affected by the milk replacer treatment.

Milk replacer intake was measured only in the first two experiments. For the first three days postweaning, pigs consumed 0.39 and 0.35 gal./day. Intake increased to 0.52 and 0.54 gal./day in the subsequent two days. On days five to seven, pigs drank 0.71 and 0.72 gal./day, respectively.

Allee notes that pigs still face a postweaning-like lag when milk replacer is removed, but it is shorter and less detrimental, as shown by heavier pigs at the end of the experiments.

In all of the studies except the first, the advantage of feeding milk replacer was maintained through day 21 to 29. The advantage is that pigs weighed 5-6 lb. more at four weeks postweaning or 3 lb. more at three weeks postweaning, when compared to pigs fed only a dry diet.

The researchers summarize that the most beneficial response comes from feeding milk replacer for three to five days postweaning. Feeding milk replacer to small pigs may be a management tool to help reduce variation among nursery pigs.

Researchers: Gary Allee, Kevin Touchette and Jeff Berkemeyer, University of Missouri. Phone Allee at (573) 882-7726 or e-mail alleeg@ missouri.edu.