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Two feeding trials from weaning to market weight were conducted with diets containing 4 and 8% crude fiber, 13 and 17% crude protein, and 2.87 and 3.48 Mcal/kg ME. The diets were computer formulated with pre-specified physical and quality requirements. A third feeding trial consisted of two levels of fiber (2.09 vs8.87%) or bulk and two levels of energy (3.50 vs2.94 Mcal/kg). Feeds in the third trial were used to determine volume of feed when wet or dry and the effect of volume and swelling capacity on feed consumption as related to bulk and energy content.Levels of crude fiber had no effect on growth rate provided energy density was adequate. The low fiber diets produced leaner carcasses than the high fiber diets, which may partially be due to added fats in the high fiber diets to equate energy levels.Crude protein level did not significantly increase growth rate when fed in diets of equal energy.

A series of feeding trials were conducted with Yorkshire pigs to determine the effects of citrus pulp on growth rate, efficiency of gain, carcass characteristics and palatability of cooked roasts. Digestible and metabolizable energy values of citrus pulp were also determined.Daily gains were significantly depressed with increasing levels of citrus pulp fed at 10, 20 and 40% of the diet although energy was held about constant by addition of prime tallow. Daily feed consumption also was depressed; however, this gave a limited feed effect and generally improved feed conversion. When estimated energy was held near constant, citrus pulp had corn replacement values of 97, 95 and 82% at the 10, 20 and 40% levels in the diet. When citrus pulp replaced corn in pelleted diets without added energy, the corn replacement value of citrus was about 95 and 78% at levels of 10 and 20% citrus pulp. Variable dietary levels of citrus pulp (2 to 45%) during the feeding period gave superior results to a constant level of 40%.There were generally no significant carcass effects due to levels of citrus pulp. Dressing percent was depressed with higher levels of citrus pulp. Increasing citrus pulp in diets with subsequent lower feed intake tended to give leaner carcasses, on the average. Cooking tests of roasts indicated no significant effect due to level of citrus pulp up to 40% of the diet.Citrus pulp dry matter digestibility averaged about 88%. Crude protein digestibility was significantly depressed with increasing levels of citrus pulp. Crude fiber and cellulose fractions of citrus pulp were highly digestible and apparent digestibility increased with increasing levels of citrus pulp.The DE, ME and MEnfor citrus pulp were 3,357, 3,194 and 3,118 kcal/kg. This indicates that present ME values for citrus pulp in feed tables need to be adjusted upward.

The differences in numbers of parasitic larvae recovered from animals in three types of lots appeared to be related to the availability and consumption of forage. Calves from drylot (no grass) had the lowest number of larvae and the highest number of adult worms, while calves from semi-drylot (limited grass) and pasture lots had significantly higher numbers of parasitic larvae and lower numbers of adult worms at postmortem.The drylot and semi-drylot animals on high protein had lower numbers of larval stomach worms than those on low protein. The animals from pasture on high protein also had a much lower larval stomach worm population than those fed less protein; but, this latter difference could not be related to protein consumption because the pasture provided an excess of protein to both high and low protein groups.There appeared to be an inverse correlation between average daily gains and average total worm loads of calves on the different treatments and levels of protein feeding but the results were not conclusive.

Limiting the feed intake of swine by hand feeding has resulted in learner carcasses (Ellis and Zeiler, 1932; Shorrock, 1940; Winters, Sierk and Cummings, 1949; Brugman, 1950; Smith, Cole and Hobbs, 1952). Woodman and Evans (1943) discussed the frequent high evaluation of forage when pigs were limited-fed poor quality diets on pasture and compared with drylot-fed pigs given similar diets containing no green forage. Morrison (1956) summarized 32 experiments where some limited feeding on forage occurred. Limitation of concentrate did not reduce the feed required per unit of gain. While there are many reports of feeding tests in which limited and equal feeding of hogs on pasture are compared with drylot, there appears to be no test comparing limited feeding diets on a weight basis but providing crude protein or energy equal to that given the full-fed hogs.The purpose of this experiment was to compare the performance of pigs receiving a full or limited intake of a diet in drylot or on pasture and to compare diets limited in weight but equal in crude protein or energy to the full-fed diets for production and carcass characteristics of swine.

Four experiments involving swine, rats and rabbits were used to evaluate the feeding value and possible toxic effects of corn damaged by Helminthosporium maydis. In a statistical analysis of two trials, TDN and apparent digestibility coefficients of ether extract, nitrogen free extract (P<.01), dry matter and energy (P<.0S) were significantly lower with diets containing the blighted corn.There was no significant (P>.05) difference in rate of gain or feed utilization of pigs and rats when given diets with normal versus blight damaged corn. However, feed efficiency was approximately 7% lower in the pig trial which may be an indication of a slight decrease of energy utilization with blight damaged corn.Pregnant rabbits were fed diets with normal or blighted corn. All does had normal gestation periods and produced normal, healthy litters. Corn damaged by Helminthosporium maydiswas palatable and did not appear to have any toxic or adverse effects on the test animals. Chemical analysis of the corn revealed that crude protein was increased and NFE portion was slightly decreased in the fungus infected grain, but there was no significant change in percent of crude fiber, ether extract or ash content of the grain.