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Three experiments were conducted to study the dietary choline requirement of young swine. Ninety pigs (three replicates), in the first experiment, and 120 pigs (four replicates), in the second experiment, were allotted to the five choline treatments (0, 330, 660, 990 or 1320 mg choline/kg of diet), fed in a 23% crude protein, semi-purified diet (.31% methionine, .33% cystine). The combined results of these experiments indicated a minimum dietary choline requirement of 330 mg/kg for pigs from 3 to 8 weeks of age (6 to 14 kg). Pigs fed 990 mg choline/kg of diet gained faster (P<.01) than pigs fed 0, 660 or 1320 mg choline/kg of diet but not faster than those fed 330 mg choline/kg of diet. Hematocrit of the pigs fed the basal diet was lower (P<.05) than that of pigs fed the other diets. Hemoglobin concentration of pigs fed the basal diet was lower (P<.05) than that of pigs fed all other diets, except the 3 30 mg/kg choline diet. There was no difference in hematocrit: hemoglobin ratio across all treatments. There was a significant linear trend (P<.05) for both hematocrit and hemoglobin concentration. Plasma alkaline phosphatase was higher (P<.05) for pigs fed the basal diet and lower for pigs fed the 660 mg choline/kg of diet as compared to the pigs fed the other diets. In the third experiment, 72 pigs (three replicates) were fed an 18% crude protein, corn-isolated soy protein diet (.23% cystine) from 4 weeks of age (7 kg) to 20 kg average live weight. The 3 × 2 factorial arrangement of treatments included 520, 760 and 1,000 mg/kg dietary choline and .22% and .46% methionine. There was no significant treatment effect on daily gain or feed conversion, indicating that the starter pig's dietary choline requirement does not exceed 520 mg/kilogram.

Experiments were conducted with 300 growing-finishing swine in confinement on slotted floors to study the effects of adding .11% Mg from MgO to a ground yellow dent corn-soybean meal (soybean seeds without hulls, solvent-extracted ground) fortified diet (table 1). Also studied were the effects of crowding, i.e., 6.86 sq ft vs4.57 sq ft per pig (.63 sq m vs.43 sq m). The higher population density reduced average daily gains (P < .01) in both tests, and increased feed/gain ratio (P< .05) in Experiment I. Pigs docked vslittermates with tails had similar performance in both population densities, with or without added Mg. In the high density populations, a significantly lower percentage of the pigs were observed to be standing and a higher percentage lying than in the low density populations. These differences were greater as the experiments progressed and the pigs increased in size. Magnesium did not significantly affect the percentage of pigs standing, lying, eating, or drinking in either the high or the low density groups.

A basal ration composed of ground yellow corn, expeller soybean meal, five percent dehydrated alfalfa meal, fortified cod-liver oil, and minerals, and which contained 17 percent crude protein was nutritionally inadequate for gestation and lactation under drylot conditions. Only 26 per cent of the pigs, averaging 17.1 pounds, were weaned by sows fed this ration. Deficiency symptoms are described.The addition of either three or six percent of sardine condensed fish solubles (fresh basis) effectively corrected the deficiency (or deficiencies) of the basal ration for gestation and lactation in drylot. Survivals of pigs so fed to weaning time were 92 and 71 percent with average weights of 31.1 and 33.7 pounds, respectively. The pigs in both groups were very growthy and thrifty. The fish solubles was apparently providing supplementary nutrients, probably vitamin-like, which were necessary for satisfactory growth, gestation and lactation.Fall-seeded rye pasture also proved to be an excellent source of the supplementary nutrients required to correct the inadequacies of the basal ration. Gilts receiving rye pasture weaned 74 percent of their pigs with a weaning weight of 31.9 pounds each.The importance of adequate nutrition during gestation as a factor in promoting successful lactation and the value of rye pasture as a vitamin supplement is clearly demonstrated. The residual effect o rye pasture as a supplement to the inadequate basal ration fed during gestation, is shown by a survival of 90 percent and an average weight of 27.4 pounds for pigs from dams so fed compared with a survival of only 26 percent and an average weight of only 17.1 pounds for pigs from dams fed only the basal ration during gestation as well as during lactation. It is suggested that the residual effect manifested was probably due to a storage of a vitamin-like factor (or factors) in the tissues of the sows while on rye pasture. These reserves were then used during lactation, thus enabling the pigs to survive and perform more satisfactorily.

SWINE breeders have been influenced, consciously or unconsciously, by growth rate in attempting to improve their hogs. This attention to growth rate is justified by the shorter feeding period and by the smaller feed requirement generally associated with an increase in growth rate. The effectiveness of such selection depends largely upon the extent to which the observed differences in growth rate are actually heritable, in the sense that the offspring will exhibit part of the superiority or inferiority in growth rate which their parents exhibited. Many estimates of heritability have been made from studies of the association between growth rates of parents and their offspring. In certain breeding experiments with both plants and animals the actual cumulative effects of selection over a number of generations have been measured to determine how much of the change resulting from selection is permanent.A classic selection experiment of this kind is the one on the composition of corn conducted by Winter (1929) and analyzed further by “Student” (1934). Similar studies have been reported for egg production in poultry by Marble and Hall (1931), for body size in mice by Goodale (1938) and by MacArthur (1944), for food consumption and utilization in the rat by Morris et al. (1933), and for feed utilization in swine by Grimes (1941).

Two experiments in which 148 head of 30-pound weanling pigs were fed to a final weight of seventy-five pounds are reported. A basal concentrate mixture of ground yellow corn, beef meal, soybean meal, alfalfa meal, and salt was compared with the basal ration plus either hulled oats, dry skim milk or dried corn distillers' solubles. The data indicate that hulled oats contributed to the nutritive qualities of the basal mixture. The mixture which contained hulled oats produced significantly more rapid daily gains and also more economical gains than the basal mixture, or the basal mixture plus dry skimmilk or dried corn distillers' solubles. The addition of the amount of dry skimmilk and dried corn distillers' solubles fed in these tests, did not improve the nutritive properties of the basal concentrate mixture used for weanling pigs.

The fortification of a basal lactation ration composed of yellow corn, tankage, soybean meal, alfalfa meal and minerals with six per cent dried corn distillers' solubles did not result in any important measurable difference in either pigs or sows up to weaning time.After weaning, a basal ration composed of ground yellow corn, wheat flour middlings, soybean meal, tankage, fishmeal, fortified cod-liver oil, and minerals was nutritionally inadequate. The basal growing-fattening ration was improved by supplementing it with dried corn distillers' solubles or alfalfa meal, and the improvement is attributed to the water-soluble vitamins contained in these products. Alfalfa meal, when used as a supplement to the basal growing-fattening rations, produced as rapid growth as the addition of six per cent dried corn distillers' solubles, but not as rapid growth as the addition of 12 per cent dried corn distillers' solubles. If the gross symptoms can be attributed to nutritional inadequacy, the alfalfa meal was a more adequate supplement (at the levels fed) in promoting normal development of feet and legs than the dried corn distillers' solubles fed at the six per cent level. However, the two products were quite comparable in promoting thriftiness of skin and haircoat, especially when the solubles were fed at the 12 per cent level.During the growing-fattening period, the pigs from the sows fed a fortified ration during lactation manifested a residual effect of the higher nutritional regime. It is postulated that the water-soluble vitamins of the distillery by-product increased the water-soluble vitamin content of the milk resulting in a storage of these factors in the bodies of the pigs, which enabled them to survive on the basal growing-fattening ration.There was degeneration of the femoral and sciatic nerves characterized chiefly by incomplete demyelination in “goose-stepping” pigs.

Studies were made with 18 litters of fall-farrowed creep-fed pigs. A basal ration of ground yellow corn, wheat flour middlings, soybean meal, tankage fish meal, minerals and fortified cod-liver oil was compared with the basal ration plus six per cent of dried corn distillers' solubles and with the basal ration plus 12 per cent of corn distillers' dried grains with solubles. Up to weaning no significant differences were noted.When rations containing the same ingredients were fed to pigs after weaning, the pigs failed to thrive normally, thus confirming the observations of other investigators that drylot rations commonly fed are nutritionally inadequate in factors other than protein, minerals, and vitamins A and D. The basal ration appeared to be adequate in quantity and quality of protein and in minerals. With 0.5 per cent of fortified cod-liver oil in the basal, vitamins A and D were not lacking. Assay values for riboflavin, niacin, and pantothenic acid indicated that the basal ration supplied more than the minimum requirements for pigs weighing 100 pounds or less. Available evidence would not lead one to suspect a deficiency of vitamins B1(Hughes, 1940a) and B6(Hughes and Squibb, 1942) in the basal ration. If the basal ration was not deficient in riboflavin, niacin, and pantothenic acid, as indicated by present knowledge, the possibility then exists that other factors known or unknown required by the pig may exist and were supplied by the distillers' by-products.The addition of either six per cent of dried corn distillers' solubles or 12 per cent of corn distillers' dried grains with solubles contributed to the nutritive qualities of the basal rations. Both of these feeds are sources of the water-soluble vitamins.Dried corn distillers' solubles were superior to corn distillers' dried grains with solubles as a supplement to the basal ration.The pigs which were fed the fortified rations up to weaning and then changed to the basal, manifested a so-called residual effect. Since the vitamin A and D content of the rations was about the same, at least a part of this effect must be attributed to the ability of pigs to store certain water-soluble factors for future use.The high death losses were probably due in part to persistent scouring in all lots throughout a major portion of the test period. Post-mortem examinations indicated involvement of the alimentary tract, but the data do not justify any conclusive statement in regard to the association of nutritional status and death losses.

The value of sunflower-seed meal was compared with meat scraps for growing-fattening swine in drylot using the paired-feeding and group-feeding techniques.In the feeding of nine pairs of young Duroc-Jersey pigs for equal gains, the rations contained 14 percent of crude protein. The protein was derived from yellow corn and alfalfa leaf meal and either 10 percent of meat scraps or 12.5 percent sunflower-seed meal. Each ration contained iodized salt and fortified vitamin A and D oil, and 2.5 percent of steamed bone meal was added to the sunflower-seed meal ration. The feed required for each 100 pounds of gain was 355 pounds and 363 pounds, respectively, in the meat scrap ration and the sunflower-seed meal ration. This difference was shown to be well within the experimental error of the feeding method employed.In the group-feeding test, three lots of twenty Duroc-Jersey pigs, each averaging about 50 pounds per pig initially, were fed in drylot.

SURVEYS show that approximately 45% of the bachelor degree graduates of mid-western colleges of agriculture will be in business or working for a business firm 5 years following graduation (Wessels, 1968, 1969). An additional 12% become owner operators or managers of farms. Farming today requires just as much business management skill as other agribusiness enterprises. Thus, about 55 to 60% of all agriculture graduates can be expected to be closely involved with business and dependent on it for their major source of income. A recent survey by Newman (1971) revealed that 60% of Purdue University B.S. graduates in agriculture were in business including farming. Of the Animal Sciences graduates (majors), 20.4% were farming and 33.3% in business for a total of 53.7%. A review of Purdue University advanced degree (M.S. and Ph.D) graduates in animal sciences indicates that 25 to 30% of them become employed by business firms (Newman, 1970). In 1968 to 1970, 25% of Purdue's Ph.D.'s in animal sciences were employed in industry, and 48% were employed by universities.

Three experiments are reported in which 136 young pigs were self-fed in drylot. The value of 5% sun-cured alfalfa meal, 4% dried whey product, 8% dried whey product and 4% fortified dried whey by-product as water-soluble vitamin supplements to a ration composed largely of corn and soybean meal is indicated. The addition of 4 % sardine condensed fish solubles or 4% dried whey product to a ration containing 5% sun-cured alfalfa meal did not improve the growth rate of weanling pigs. The above levels of whey products induced a somewhat laxative condition in the pigs.In experiment 2, lactose was found to be a constituent of dried whey which contributed to the laxative condition. In all tests it was observed that the laxativeness was not detrimental to the rate or economy of gains. Pigs fed rations containing 1.1% or 1.7% lactose for 28 days scoured less than those fed rations containing 2.4% lactose.

For weanling pigs, the practical minimum level of riboflavin appears to be approximately 1.4 mg. per pound of ration consumed in the drylot experiments herein reported.Hughes (1940) reported a minimum requirement of between 1 and 3 milligrains of riboflavin per 100 pounds body weight per day. This would be equivalent to 0.25 to 0.75 rag. per pound of ration consumed if the pig ate 4 pounds of feed per ioo pounds of body weight daily. The National Research Council Committee on Animal Nutrition (1944) recommends 3.8 milligrams of riboflavin daily per day for a 100-pound pig, or .76 milligram per pound of ration. Van Poucke and Krider (1946) reported more rapid and more efficient gains of weanling pigs fed 1.5 milligrams of riboflavin per pound of purified diet than when 0.5 or 0.75 rag. was fed.

These studies involved the use of records from 393 spring and fall farrowed pigs produced in the Cornell University Experiment Station herd. The Berkshire, Chester White and Duroc Jersey breeds and their crossbreds were included in the studies. The pigs were full-fed from weaning time.An analysis of the data collected during 1939–40 and 1940–41 shows a highly significant correlation between condition as determined by visual observation and the average thickness of back fat in the carcasses. On the other hand it was not possible to estimate the thickness of back fat by handling the live hogs before slaughter. The thickness of the back fat was greater as the live weight of the hogs increased and, as expected, there was a highly significant correlation between live and dressed weights.The results of the work done in 1941–1942 are in accord with that of the previous work in the relationship between live weight and thickness of back fat and also between live weight and dressed weight.The results of detailed studies of six characteristics involving 30 head each of the Berkshire, Chester White and Duroc Jersey hogs made to determine certain other relationships are shown in table 1.Highly significant correlations were obtained between several of the factors studied, however, there was little or no correlation between the fatness of the pig and the development of loin-eye muscle or the lean in the end cut of the ham.The area of the loin-eye muscle is correlated with weight but less so than with several other factors studied.There was a highly significant correlation between the area of the loin-eye muscle and the area of the lean in the end cut of the ham.The circumference of the ham is influenced by the fatness of the pig.Certain differences were found between the breeds studied, but more extensive work should be done with hogs from different sources before general conclusions are drawn.

Our students of today have tremendous opportunities to become tomorrow's leaders in research, education, extension, agribusiness, government and other areas.Our product—the student—is our number one responsibility.Our objective must be to provide appropriate and changing education and training for this leadership of the future.In business, as in other areas of employment, personality traits such as honesty, determination and loyalty receive as much or more consideration as know-how! Maturity, judgment, initiative, enthusiasm and ability to work and get along with other people are qualities sought by employers. These traits are not held exclusively by animal science or agriculture graduates, but are found in graduates from other areas. Our graduates having these sought characteristics will receive starting salaries comparable to most others.We need to help students attain breadth in their programs as well as depth in specialized areas. We must reduce our “busy work”—how to do it—in curricula and provide elective hours (preferably one-fourth to one-third of the total for graduation) for courses in communications, economics, chemistry, business, humanities, social sciences and areas of specialization. Such changes do and will require more emphasis on excellent teaching and strong dedicated counseling.If we aggressively pursue our convictions along the lines discussed, we should be able to look back proudly to the results derived from preparing our students for tomorrow's opportunities as leaders in agribusiness, as top-notch farm business operators, as careful researchers with originality, as inspiring teachers and counselors, as extension leaders who will emphasize more of the “why” rather than the “how” to do it, and as leaders in the private enterprise society in their communities, states, the nation and the world!

Two lots of 15 pigs each were self-fed shelled yellow corn and mixed supplement on winter rye pasture from an average initial weight of 101 pounds to an average final weight of 226 pounds to study the effect on carcass quality and rate and efficiency of gain of feeding corn containing 4.7% fat and 9.0% crude protein as compared with corn containing 6.4% fat and 10.8% crude protein (analyses on a dry basis). No significant differences occurred between the two groups in rate of gain, dressing percentage, carcass grade, carcass firmness grade, backfat thickness and refractive index of body fat. Fat samples from hogs fed the higher fat corn had an average iodine number of 65.81 as compared with 63.84 for fat samples from hogs fed the low-fat corn (odds 10:1). The total feed eaten per 100 pounds gain was practically the same for each group, but the pigs receiving the higher fat corn, which was also higher in crude protein, consumed 27% less mixed supplement per unit of gain.

In a drylot growing-fattening test with weanling pigs a regular solvent soybean oil meal, a “special” solvent soybean oil meal processed for 45 minutes at atmospheric pressure in the presence of live steam, and a high-protein solvent soybean oil meal were equally effective in promoting rate of gain when rations contained 20% crude protein were fed. The addition of 25 mg. aureomycin HCl per pound of ration increased gains very significantly (28%). Pigs receiving 5% dried whey-product with whey fermentation solubles and vitamin B12concentrate gained 15% faster than pigs receiving this product without the vitamin B12concentrate, but the difference was not statistically significant.In a second experiment the effect on gains and carcass characteristics of adding 10, 20 or 40 mg. of streptomycin per pound of ration fed to growing-fattening pigs in drylot from 75 to 225 pounds in live weight was studied. Pigs receiving 10 mg. streptomycin per pound of ration gained significantly faster (11%) and pigs receiving 40 mg. streptomycin per pound gained very significantly faster (19%) than pigs fed the basal ration. There were no significant differences in thickness of backfat or in other physical carcass measurements studied. There was a very minor accumulation of the antibiotic in the loin tissue and backfat of hogs fed 40 mg. of streptomycin per pound of ration (1.3 mg. streptomycin per pound of loin tissue and 0.5 mg. streptomycin per pound of backfat).

Growing-fattening pigs self-fed to 200 pounds required 5.5% more concentrates per 100 pounds of gain on bromegrass than on alfalfa pasture. The pigs on alfalfa pasture consumed 33 % less protein supplement and 13% less minerals per unit of gain and reached the final weight one week earlier.Bromegrass-alfalfa pasture was fully equal to alfalfa pasture for self-fed pigs.In comparisons within experiments on similar pastures, the rates of gain between groups of pigs differed slightly but not significantly when the following supplemental mixtures were self-fed free-choice with shelled yellow corn and minerals (parts by weight): (a) 100 tankage (60% crude protein) plus 100 expeller soybean oil meal; (b) 200 expeller soybean oil meal plus 100 alfalfa meal; (c) 100 expeller soybean oil meal plus 200 ground oats; (d) 100 meat and bone scraps plus 100

Three tests are reported in which weanling pigs were fed a 20% crude protein corn-soybean oil meal basal ration in drylot. The intramuscular injection of 1 ml. reticulogen per pit; per week did not improve the rate of gain over that produced by pigs not receiving the reticulogen treatment when 9 vitamins of the B complex were included in the basal ration. The basal ration including expeller soybean oil meal and 7 vitamins of the B complex was improved although not significantly so by either 4% dried whey product with whey fermentation solubles, 5% meat scraps or .05% Merck's APF supplement, while the addition of 1.1% Lederle's APF supplement significantly improved the rate of gain.When the basal ration contained solvent soybean oil meal, growth rate was not improved by the addition of either choline chloride or Merck's APF supplement. The latter supplement and all other

A 20% crude protein corn-soybean meal ration fortified with minerals, vitamins A and D and 6 vitamins of the B complex (including a B12concentrate) was not improved by the addition of either choline or betaine. Since, in a previous test, choline significantly improved a similar ration without the vitamin B12concentrate it is suggested that B12has a sparing effect on the choline requirement of the pig.The two solvent soybean meals used were superior to expeller soybean meal, using rate of gain as the criterion, when fed in rations equated to contain 20% crude protein.

The value of the pig creep for nursing pigs was studied in six experiments with 134 sows and their litters on pasture.An average of the first three experiments showed that spring pigs creeps-fed a simple ration of shelled yellow corn and supplement (2 tankage, 1 soybean meal) made 12 percent faster daily gains and suffered fewer death losses than those not creep-fed when sows were fed a “poor ration” of ear corn (full-fed by hand twice daily) and minerals on rye pasture. The sows and litters in the creep-fed lot required 20 percent less feed per unit of gain than those in the no-creep lot.In two comparisons (experiments 4 and 5) there was no significant advantage in creep-feeding pigs a mixed ration when the sows and litters were self-fed shelled yellow corn and supplement free-choice on rye pasture (spring) or brome-bluegrass pasture (fall). The daily consumption of the mixed creep-ration was so small (0.36 lb. per litter) that it would not have been expected to exert a significant effect.In the sixth experiment, the sows and pigs were self-fed shelled yellow corn and supplement free-choice on Balbo rye pasture with alternate lots of pigs being offered shelled corn, broken oat kernels and supplement free-choice in a creep. During the test 9 percent of the pigs died in the no-creep lot while only 4 percent of the pigs died in the creep lot. A slight, but statistically insignificant, increase in gains was obtained by creep-feeding. The average creep-ration consisted of about 8 percent shelled yellow corn, 76 percent broken oat kernels and 16 percent supplement, and contained 21 percent crude protein. In the creep lot, 12.5 percent less feed was required per 100 pounds of net gain of sows and pigs.

Five drylot tests involving 286 weanling pigs fed to approximately 100 pounds live weight were conducted to study the value of condensed fish solubles, semi-solid Redfish product, semi-solid fish product from Cod and Haddock, Menhaden fish meal, dehydrated alfalfa meal, dried fermentation solubles, and combinations of certain of these products. In three of these tests, the weanling pigs used had been raised in drylot while those used in two tests had been produced by sows on pasture. All rations were equated for crude protein.The responses of weanling pigs to vitamin supplements were greater and more consistent when they had been raised since birth in drylot rather than on pasture. This indicates that the pigs on pasture until weaned stored vitamins in their body tissues which enabled them to respond satisfactorily on a basal ration that was deficient for pigs that had been in drylot until weaned.A 20% protein ration composed of ground yellow corn, 6% meat scraps, soybean meal, minerals and fortified A and D oil was inadequate for weanling pigs that had been in drylot since birth.

Favorable growth responses were obtained when sufficiently high levels of a vitamin B12concentrate were added to the basal alpha-protein diet, which is low in vitamin B12.When 50 micrograms of vitamin B12per Kg. of dry matter of the diet were fed, optimum growth rates were obtained. The addition of more vitamin B12concentrate did not result in a further growth response.Even the highest levels of vitamin B12concentrate fed did not induce completely normal hematopoiesis in 77 days of observation, as indicated by an abnormally high total erythroid percentage in the bone marrow.Gross symptoms which might be attributed to the deficiency existing in the basal diet were hyper-irritability, posterior incoordination, voice failure, and pain in the rear quarters.

Within the limits of the conditions covered in the study, the following conclusions appear justified:Thiouracil fed as 0.15% of the ration causes increased retention of nitrogen in the body during the second and third weeks of feed ng, the period of time that the drug causes the greatest increase in daily gains.Neither the physical nor the chemical composition of the carcass is modified significantly when fattening barrows are fed thiouracil during a 4-week period.Thiouracil causes partial inhibition of skeletal growth, lowers dressing percentage about 1%, but has no significant effect on thickness of backfat, cutting yields, carcass grade and carcass firmness.

Ninety-five gilts and sows which had shown impaired fertility were obtained in 1948 and 1949 from Illinois swine producers and from the University of Illinois for study. Of these, 16 were not included in the study for various reasons. Of the remaining 79 females 53.2% conceived on the study but they must still be regarded as being "hard-to-settle." The rest showed various abnormalities which were responsible for their sterility or low fertility. The most important abnormalities were: tubal aberrations, cystic follicles, and blind or missing portions of the reproductive system. Very little evidence of complete embryonic mortality in individual females was obtained in this sample. The difference between the number of corpora lutea and the number of fetuses indicated that about 26% of the ovulated eggs did not develop into embryos.

A 20% crude protein ration composed largely of corn and soybean meal was nutritionally inadequate for weanling pigs in drylot. The addition of either 1.5 mg. riboflavin, 6 mg. pantothenic acid or 250 mg. choline chloride per pound of ration significantly increased the average daily gains, while neither thiamine, niacin nor pyridoxine as additions to the basal ration had a significant effect on the rate of gain.When the basal ration included five B-vitamins, the addition of either 250 mg. choline chloride per pound of ration or 0.2% dl-methionine or a combination of both very significantly increased the growth rates. The choline-methionine combination produced results which did not differ significantly from those obtained when either choline or methionine was fed. This indicates that the basal ration satisfied the indispensable choline and methionine requirements of the pigs but did not provide enough additional methyl groups for optimum growth.When the basal ration included six B-vitamins, the addition of either 5% meat scraps or 2% dried whey-product with whey fermentation solubles increased the average daily gains, although not significantly. Either 5% meat scraps plus 1% dried whey-product with whey fermentation solubles or 2% condensed menhaden fish solubles resulted in a highly significant increase in growth rate to 75 pounds. The average daily gain to 100 pounds was increased appreciably by the 2% fish solubles, but the increase was not statistically significant. The addition of 4% penicillium meal did not improve the rate of gain. The addition of 8% dried skim milk resulted in a highly significant increase in the growth rate to 75 and 100 pounds, while the addition of 4% dried skim milk plus 2.5% meat scraps significantly increased the rate of gain both to 75 and 100 pounds. Performance of pigs in these tests indicates that meat scraps is probably a source of the animal protein factor(s),that dried whey-product with whey fermentation solubles contains the factor S group and that the combination of these two feeds, condensed menhaden fish solubles and dried skim milk contain both the animal protein and factor S groups. These responses of pigs are similar to those reported in poultry researches.

Using the paired-feeding, trio-feeding, group-feeding and individual-feeding techniques, 109 fattening swine were fed to determine the practical optimum level of thiouracil to include in the ration and the effect of this level on rate and efficiency of gains.Within the limits of the conditions covered in the study, the following conclusions appear justified.Of the levels of thiouracil tested (0.1%, 0.15%, 0.20%, and 0.25%),0.15% represents the most nearly optimum level to add to an adequate ration for fattening barrows weighing 140 to 180 pounds initially. For the remaining purposes of this study, this level of the drug was used.Under conditions of equalized feed intake, thiouracil increases the rate of gain of pigs significantly and reduces the amount of feed consumed per unit of gain significantly.When comparable pigs are fed to the limit of appetite either individually or in groups, adding thiouracil to an adequate ration does not increase the rate of gain but it does significantly reduce the amount of feed required per unit of gain as well as the feed consumption.

In 1945 work was started at Illinois on the development of a “synthetic” diet for young calves in order to study the water-soluble vitamin requirements of ruminants. Since the “synthetic milk” diet developed was used successfully in the rearing of calves, it appeared worthwhile to attempt to rear baby pigs on the same diet.It was hoped that by starting with the very young animal it might be possible to produce deficiencies that do not appear in weanling or older pigs. Such animals would not have an opportunity to build up large body stores of the vitamins from the sow's milk and their rapid rate of growth should mean high requirements. Thus, the baby pig seemed an ideal experimental animal with which to study certain nutritive requirements of swine. It was also hoped that studies on baby pigs would lead to useful information applicable to infant nutrition.

Since 1943, workers at the Illinois Station have been studying the nature of the deficiencies of a ration composed chiefly of corn and soybean meal with essential fat-soluble vitamins and minerals added for weanling pigs continuously fed in drylot. The basal ration contained 20% total protein and was composed of ground yellow corn 52%, wheat flour mid-lings 15%, expeller soybean meal 30.5%, fortified vitamin A and D oil 0.5% and minerals 2%.Although this ration was improved for weanling pigs by the addition of the six crystalline B-vitamins (B1, B2, B6, pantothenic acid, niacin and choline), optimum growth was still not obtained (Krider et al.,1943, Fairbanks et al.,1944). The B-vitamins were added to supply amounts in excess of the pig's known requirements, or at the rate of 150 mg. thiamin, 150 mg. riboflavin, 500 mg. niacin, 600 mg. pantothenic acid, 250 mg. pyridoxine and 150 grams choline chloride per 100 pounds of the ration. Fairbanks, Krider and Catron (1944) reported that 6% distillers' solubles or 10% alfalfa meal supplemented such a plant protein basal ration, but growth rates were still subnormal even with these supplements added. Furthermore, their experiments indicated that the inclusion of animal proteins (tankage and fishmeal) along with plant proteins in otherwise complete rations for weanling pigs confined in drylot from birth increased growth rates and markedly reduced death losses, compared with results obtained when pigs received only plant protein supplements. The animal protein feeds were considered to be of value chiefly because of their

A basal ration composed of ground yellow com, expeller soybean meal, tankage, 5% dehydrated alfalfa meal, vitamin A and D oil, and minerals was nutritionally inadequate for yearling sows and for gilts fed in drylot during gestation and lactation. Only 37% and 9% of the pigs were weaned, respectively, by the yearling sows and the gilts fed this ration. Deficiency symptoms observed in the second test are described in detail.The addition of either 0.5%, 1.0% or 2.0% of dried fermentation solubles (B-Y) did not correct the deficiency (or deficiencies) of the basal ration.Slight improvement was noted, however, especially in the survival of pigs when the basal diet was fortified with the riboflavin carrier.The first limiting deficiency (or deficiencies) of the basal ration apparently was not riboflavin.One percent of sardine condensed fish solubles supplied the nutrients needed to correct the first limiting deficiency (or deficiencies) of the basal ration.Very significant improvement in 56 day weights of the pigs was found when 1 % of dried fermentation solubles was supplied in addition to 1% of fish solubles.The pigs produced by sows fed the latter supplements were sleeker, growthier and smoother than pigs from sows not fed the riboflavin carrier.Comparable results were obtained when sows were fed combinations of either 1% or 2% of fish solubles with 1% dried fermentation solubles. Gestation-lactation performance of sows fed in drylot was significantly improved by feeding rations containing 2.3 milligrams of riboflavin per pound as compared to feeding rations containing 1.2 milligrams of this vitamin per pound. The additional riboflavin (1.1 milligrams per pound of diet) was supplied by dried fermentation solubles.

Young male rats were trio-fed (equal feed) for six weeks on diets equated for crude protein (15%) and energy to compare yellow corns containing 8.6%, 11.2% and 13.5% crude protein (fresh basis). In each diet the amount of protein supplied by corn was the same. No significant differences occurred in growth rates or in gross energy content of the carcasses.In a similar test with nine pairs of pigs pair-fed (equal feed), yellow corn containing 11.7% protein was no better than yellow corn containing 8.2% protein when each furnished the same amount of protein in the ration.In another experiment with pigs (trio-fed, equal feed) fed equal amounts of corn containing 7.7%, 9.1% and 12.8% crude protein, with enough protein supplement to raise all rations to a 15% protein level (12% after the pigs reached 100 pound Weight), average daily gains made by pigs fed the 12.8% protein corn were significantly less than those made by pigs fed the corn of lower protein content. Average daily gains did not differ significantly between pigs fed either 7.7% or 9.1% protein corn. Twelve percent less protein supplement was needed to produce a 15% protein ration and 27.7% less supplement was needed to produce a 12% protein ration when the 9.1% protein corn was used than when the 7.7% protein corn was used.

Weanling pigs that had been confined in drylot from birth were fed a basal ration of ground yellow corn, wheat flour middlings, soybean meal, fish meal, tankage, minerals and fortified cod-liver oil or the basal ration supplemented with either (1) crystalline B-vitamins (2) six percent dried corn distillers' solubles, or (3) ten percent of alfalfa meal. The basal ration was very inadequate even though chemical analyses and vitamin assays indicated that it was adequate in the nutrients known to be required by the pig.Supplementing the basal ration with six percent of dried corn distillers' solubles increased the gains 16 percent and death losses were decreased.When the basal ration was supplemented with thiamin hydrochloride, riboflavin, nicotinic acid, calcium pantothenate, pyridoxine and choline chloride, growth response was increased and death losses were reduced from 31 to 9 percent. This supplementation was not as complete nutritionally as the addition of ten percent of alfalfa meal, but was more effective than dried corn distillers' solubles.

A basal ration composed of yellow corn, soybean meal, tankage, fish meal, fortified cod-liver oil and minerals was nutritionally inadequate for gestation and lactation under drylot conditions.The addition of either six or twelve percent of dried corn distillers' solubles, a combination of alfalfa meal and dried solubles, alfalfa meal, or six crystalline B-vitamins improved breeding efficiency, fertility and the strength of the pigs farrowed. The value of the alfalfa meal and the solubles is attributed to the water-soluble vitamins, known or unknown, contained in these products.Feeding during gestation is an important factor for satisfactory results during lactation and must not be ignored when considering the question of high mortality among baby pigs.The residual effect of feeding rations fortified with B2-complex supplements during gestation was manifested during the lactation period when all groups received the basal ration. Only 13 percent and 7 percent of the pigs were weaned by the basal sows, while 83 percent and 82 percent of the pigs were weaned by the sows fed alfalfa meal during gestation, and the basal ration during lactation. The importance of adequate nutrition during gestation and the value of alfalfa meal as a vitamin B2-complex supplement is clearly demonstrated. Sows fed the combination of 6 percent solubles and 4 percent alfalfa meal during gestation weaned 85 percent of their pigs although they were fed the basal ration during lactation. The six crystalline vitamins were effective in supplementing the basal ration, but the residual effect was not manifested to the same degree as in the groups fed natural vitamin carriers. This indicates either a greater tissue storage of the known factors or a storage of unknown factors by the groups fed alfalfa meal or the solubles-alfalfa meal combination.In the interpretation of the differences in the lactation performance of sows due to ration differences, consideration of the adequacy of the rations fed during the gestation and even the growing periods should be considered.