COMPARISON OF PROTEIN SUPPLEMENTS FOR SWINE WITH DIFFERENT CROSS-BREEDING PROGRAMS
Research Progress Report 38 August 1962
J. R. Foster, V. A. Garwood, H. W. Jones and R. A. Pickett, Animal Sciences Dept.
SUMMARY
Pigs fed the modified supplement 2, which contained 20 percent meat and bone scraps and 10 percent alfalfa meal, gained significantly faster than the pigs fed either a fortified soy supplement or Purdue Supplement 5.
The pigs from the line breed cross gained significantly faster and made more economical gains than those from either of the other breeding groups. The gains on the two breed cross and the three breed cross are somewhat lower than the gains of pigs from similar breeding programs on this farm. Therefore, we cannot say the gaining ability of the pigs in this experiment are necessarily typical of the breeds involved.
Under the conditions of this experiment the pigs did not over-eat on protein supplement in any lot. Carcass data will be collected on the five barrows from each lot.
PROTEIN SUPPLEMENTS FOR SWINE
Research conducted at Purdue and other experiment stations has demonstrated the necessity of adding certain vitamins and minerals to soybean oil meal to make a nutritionally adequate protein supplement to be fed with corn. There are many vitamin and trace mineral premixes on the market for supplementing soybean oil meal.
One disadvantage cited for using soybean oil meal where grain and supplement are fed free-choice has been that this sup-
plement is extremely palatable and that hogs may over-eat on supplement. Therefore, it is common to add some alfalfa meal and/ or a source of animal protein to reduce the palability.
An early protein supplement developed at Purdue is Purdue Supplement 5. This supplement, which is shown in Table 1, consists of 5 sources of protein with no vitamins or minerals added. One of the objectives of this experiment was to compare three protein supplements--(1) soybean oil meal plus vitamins and minerals; (2) a supplement containing 20 percent meat and bone scraps and 10 percent alfalfa meal plus vitamins and minerals and (3) a combination of five protein sources with no added vitamins or minerals.
CROSS-BREEDING PROGRAMS
It is generally thought that certain traits in swine production can be improved by crossbreeding. This improvement by crossbreeding is usually greater on traits that are relatively low with respect to herit-ability such as litter size, birth weights, and, possibly, gaining ability and feed efficiency.
A second objective of this experiment was to evaluate three different crossbreeding programs used on the Purdue Experimental Farms.
EXPERIMENTAL PLAN
Three breeding groups of 30 pigs each were randomly allotted to three protein supplement treatments on the basis of weight, sex and litter. The 90 pigs were assigned to nine lots with 10 pigs per lot. Each treatment group was self-fed shelled corn and
PURDUE UNIVERSITY • Agricultural Experiment Station • Lafayette, Indiana