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Cement kiln dust (CKD), samples of which have been reported to stimulate growth in cattle and sheep, was fed to weanling pigs in a 42-d experiment. CKD at levels of 1.5 and 3.0% was added to a corn-soybean meal-oats-whey-type diet containing inadequate amounts of Ca (.4% of the diet) to provide final dietary Ca levels of .85 and 1.3%. A diet containing 3% limestone (1.3% dietary Ca) served as a positive control. Body weight gain was depressed by 3.0% CKD, and histopathological lesions of the humerus, not typical of nutritional secondary hyperparathyroidism or rickets, were observed. The lesions detected were osteonecrosis, thinning of the cortex and reduction in the width of the epiphyseal cartilage. Width of the proximal epiphyseal plate and cortical index of the humerus (width of cortex divided by total diameter at narrowest point of diaphysis) were smaller in pigs fed 3% CKD than in pigs fed 3% limestone. CKD contained 2.3% Al, 15 ppm Cd and 110 ppm Pb, providing 690, .45 and 3.3 ppm of Al, Cd and Pb, respectively, in the diet containing 3% CKD. Kidney, liver and bone ash concentrations of these three minerals were not increased by CKD, and typical toxicity signs were absent. It is concluded that CKD may contain one or more factors that interfere with normal bone metabolism in growing pigs when the diet contains 3.0% CKD.

Methane generation has been proposed as a means of swine waste disposal. As a secondary treatment to recover nitrogen, carbon and other nutrients from the effluent of a methane generator, Arthrospira platensis(a blue-green alga also known as Spirulina) was grown and its nutritive value determined. This alga contained 55 to 61% crude protein and was easy to harvest. Three indoor culture ponds of .65 M2were designed and built. The ponds consisted of a bottomless wooden frame lined with a polyethylene sheet resting on a table top. Culture medium was kept circulating by a special aerator. An inorganic medium was evaluated. When algal growth reached a saturation point, there was still 70% of N03—and 11% of HCO3—left unused in the medium. Swine waste fermented at a hydraulic retention time of 10 days gave the highest ratio (2.3:1) of NH3-N to TKN (about 70% NH3-N). NH3seemed to support best the growth of algae, when the effluent was slowly infused. Organic acids in the effluent also provided a good source of carbon, a limiting factor when algae were intensively grown. Under the light intensity of 500 footcandles, Arthrospirayielded about 5 g/M2/day. A sample containing 2,038 mg of NH3-N produced 16,250 mg of dry algae, containing 9,750 mg protein or 1,560 mg N, giving an efficiency of nitrogen recovery of 76%. The protein of Arthrospira platensisshowed a PER of 2.25, apparent nitrogen digestibility of 76.7% and biological value of 67.7%; no toxic effects were noted.

Two experiments were completed with a total of 54 5- to 7-week-old weanling Yorkshire pigs to determine (Experiment 1) the tissue retention of dietary selenium (Se) present in white sweet clover (Melilotus alba) relative to that provided as sodium selenite (Na2SeO3) and (Experiment 2) the tissue retention and liver distribution of Se present in fly ash incorporated into the diet.In Experiment 1, groups of four pigs each were randomly allotted to corn-soybean meal-type diets containing 5 or 10% white sweet clover grown either in low Se soil (.03 ppm Se in clover) or on fly ash (70 ppm Se in clover). Na2SeO3was added to the low Se clover diets to provide 0, 3.5 or 7.0 ppm of Se. Se concentrations of kidney, liver and skeletal muscle after 61 days were increased more by fly-ash grown sweet clover than by Na2SeO3, but blood Se was increased more by Na2SeO3. No histopathological lesions were found in liver, kidney, heart, pancreas or skeletal muscle. Diets had no effect on weight gain or feed to gain ratio.In Experiment 2, 30 pigs were fed from weaning to 92 kg slaughter weight on a corn soybean meal-type diet containing 0, 1, 2, 4 or 8% fly ash (5.7 ppm Se). Fly ash had no effect on weight gain and no histopathological lesions were found in heart, liver, kidney, pancreas or skeletal muscle. Tissue Se concentrations increased progressively with graded levels of fly ash in the diet. Distribution of Se in eight different sites in the liver was uniform. It is concluded that Se supplied in the diet as a component of fly ash or of white sweet clover grown on fly ash (probably as a constituent of seleno-amino acids) is absorbed and utilized for tissue deposition by the pig. The toxicological potency of clover-borne Se and its ability to alleviate vitamin E - Se deficiency signs relative to that of Na2SeO3remain unknown.

The objective was to study control of mature size by characterizing metacarpal growth plate closure in relation to relevant bone growth-regulating hormones in two breeds exhibiting distinct differences in mature frame size. Thirty-four Suffolk and 34 Dorset ram lambs were slaughtered in pairs within breed at birth, weaning and monthly intervals until 420 d and then bimonthly to 600 d. Plasma growth hormone was depressed to undetectable levels due to the high-energy, ad libitum-fed diet. Plasma insulin-like growth factor-I (IGF-I) rose over the growth period from 116 ng/ml (newborn Suffolk) to a high of 451 ng/ml (420-d Dorset); it appeared to peak at approximately 400 d and then declined to a stable level. Dorsets consistently exhibited higher IGF-I levels. The thyroid hormones exhibited no apparent age association. An age-associated rise was detected for testosterone, but not for estradiol. Mature metacarpal lengths were estimated to be 147.2 and 127.4 mm for Suffolks and Dorsets, respectively. Ninety-five percent of mature length was attained in Suffolks by 226 d and in Dorsets by 165 d. Growth plates, however, did not begin to appear closed until 390 d and closure was not complete in all animals until 480 d, suggesting that metacarpal growth rate was dissociated temporally from growth plate closure. Although growth plate closure likely is controlled by the endocrine system, there were no apparent relationships between circulating hormones and growth plate width, age at closure or zonal divisions within the growth plate, suggesting that the growth plate experiences a very different hormonal environment than what can be measured in the circulating blood.

Twenty-four weanling Yorkshire pigs were used in a 2 × 2 × 2 factorial arrangement of treatments to determine their response to high levels of dietary lead (Pb) (1,000 ppm) and zinc (Zn) (4,000 ppm) (as lead acetate and zinc oxide), to investigate the influence of high dietary calcium (Ca) (1.1%) on the biochemical and morphological manifestations of Pb and Zn toxicity, and to determine the effect of excess Zn on Pb toxicity. Clinical signs of Pb toxicity included behavioral changes, lameness, and anorexia. Pb content of blood, soft tissues, and bone was increased markedly by 1,000 ppm Pb in the diet during the 13-week experiment. Zn and Pb fed together, as compared with Pb alone, tended to increase Pb levels in blood, soft tissues, and bone and to enhance the toxic effects of Pb as shown by reduced weight gains, severe clinical signs, and pathological changes. High Ca reduced blood and bone Zn and Pb concentrations. The results indicate that high dietary Ca has a protective effect against the adverse effects of diet Pb and Zn, and that Zn aggravates Pb toxicity in growing pigs.

Two levels each of Cu, Fe and ascorbic acid (AA) were used in a factorial arrangement in diets fed to 3-week-old pigs in an attempt to determine the influence of high levels of dietary Fe and AA on the deleterious effects of 250 ppm dietary Cu, to ascertain the mode of action of high Cu in inducing anemia and to delineate the effects of high dietary AA on Fe and Cu metabolism. Pigs fed high Cu had decreased plasma and liver Fe concentrations, increased latent and total Fe binding capacity, decreased saturation of transferrin, increased rate of removal of intravenously administered 59Fe from the plasma and increased utilization of 59Fe by RBC, all manifestations of Fe deficiency. The rapid uptake of 59Fe by RBC, low levels of tissue Fe and low degree of transferrin saturation indicate no block in Fe release from the reticuloendothelial system. Liver Cu concentration of pigs fed high Cu was greatly reduced by addition of 0.5% AA to the diet. AA had no effect on altering the level of Fe retained in the liver or intestine, but did increase the plasma Fe level, the degree of saturation of plasma transferrin, and the rate of removal from plasma and uptake by RBC of 59Fe. It is concluded that the Fe deficiency induced by high dietary Cu is due to impairment in Fe absorption from the gastrointestinal tract and that this impairment is ameliorated by AA.

Cestrum diurnum(day-blooming jessamine) has been proposed to cause calcinosis in horses and cattle in Florida. The present studies investigated some physiological properties of the plant, using the chick as the experimental animal. The inclusion of dried leaf powder in a rechitogenic diet restored intestinal calcium-binding protein synthesis (CaBP) and increased calcium absorption in the cholecalciferol-deficient chick. The estimated level of cholecalciferol-equivalents in the dried leaf was about 30,000 to 35,000 IU/kg. Most of the activity was extractable with methanol:chloroform (2:1), indicating that the major cholecalciferol-like component in C. diurnumwas different from the water soluble factor(s) in Solanum malacoxylon. The time course of effect of C. diurnumextract in rachitic chicks was similar to that of 1,25-dihydroxycholecalciferol but the former had a longer lag time. The strontium fed chick, in which the kidney 25-hydroxycholecalciferol-1α-hydroxylase is inhibited, responded to C. diurnumextract, confirming the 1α, 25-dihydroxycholecalciferol-like character of the Cestrumfactor. The extract also appeared to interact with the intestinal 1α,25-dihydroxycholecalciferol cytosol receptor although this observation is preliminary. These findings indicate that the 1α,25-dihydroxycholecalciferol-like principle in C. diurnummay cause excessive calcium and phosphate absorption leading to calcinosis.

The localization of a plasma membrane calcium pump in the oviduct of the laying hen was investigated by immunohistochemical techniques, utilizing a monoclonal antibody (5F10) produced against the human erythrocyte calcium pump. This antibody was shown to react with an epitope of the pump in oviductal tissue, and prominent staining was observed on the microvilli of the tubular gland cells of the hen shell gland (uterus) and the isthmus. The Ca2+ pump was not detectable in the infundibulum or the magnum. Calbindin-D28k, also localized by immunohistochemical means, was observed to be present in the tubular gland cells of the shell gland and the distal isthmus (adjacent to shell gland) but not in either the proximal isthmus (adjacent to the magnum), the magnum or the infundibulum. The localization of the Ca2+ pump in the oviduct corresponds to known sites of mineral deposition during egg shell formation. The distribution of calbindin-D28k differed, co-localizing with the Ca2+ pump in the shell gland and distal isthmus but not in the proximal isthmus. This might reflect a greater rate of active Ca2+ secretion in the distal isthmus and shell gland as compared to the proximal isthmus.

Thirty-two Yorkshire pigs (49 kg body weight, 108 days of age) were used to determine the effect of feeding-fasting interval on rate of body weight gain, feed utilization and carcass and organ measurements at a slaughter weight of approximately 90 kilograms. Treatments were: (1) Continuous ad libitumfeeding,(2) ad libitum1 day, fasted on alternate days, (3) ad libitum1 day, fasted 2 days, (4) ad libitum1 day, fasted 3 days. Average daily gain was reduced progressively as severity of the fasting-feeding interval was increased. Efficiency of feed utilization, likewise, was reduced as the severity of feed restriction increased, except in group 2(1 day ad libitum-1 day fasted) in which efficiency was not significantly different from that in group 1 (continuously ad libitum). Pigs with access to feed only part of the time were able to compensate partially for the time away from feed by consuming more feed during the time of free access to feed.Dressing percent, chilled carcass weight and backfat thickness were progressively reduced and percent lean cuts increased as proportion of fasting time increased. Weight of the empty stomach and intestines progressively increased, as a percentage of carcass weight, as proportion of fasting time increased. Pituitary and thyroid weights, as percentages of carcass weights, were drastically increased by the most severe fasting interval (group 4), although less severe fasting (groups 2 and 3) was not associated with an increase in their weights. Liver fat percentage and liver and kidney weights were not affected by treatment. Adrenal gland weight was increased by the two most severe fasting intervals and this was associated with an increase in thickness of the glomerulosa and fasciculata-reticularis. No other histological changes were noted in any tissue. Myristic and linoleic acid concentrations in both middle and outer layers of backfat decreased as proportion of fasting time increased, while stearic and oleic acid concentrations increased and palmitic remained unchanged.

Eighteen 4-week-old Yorkshire and Hampshire pigs were used in 2 experiments to follow the distribution of 45Ca in different parts of the skeleton after intraperitoneal (experiment 1) or intravenous (experiment 2) injection. The 45Ca concentration (microcuries of 45Ca per mg. total Ca) of the nasal turbinate paralleled that of the proximal and distal ends of the humerus, reaching a peak after 6 hr. and remaining through day 4 followed by a decline from day 4 to 8 and a further decline from day 8 to 16. The shaft of the humerus remained at a constant 45Ca concentration throughout the 16-day period, probably reflecting early uptake by the subperiostium and subsequent trapping of the isotope in deep layers of bone as accretion continued. The femur showed the same trend.The first lumbar vertebra and mandible were similar in activity to the ends of the femur and humerus and to the nasal turbinates at each time interval. The teeth showed the lowest activity and the frontal bone was intermediate.There was a rapid disappearance of 45Ca from the blood following intraperitoneal injection, but a small amount persisted even 16 days after injection, probably reflecting reentry into the circulation after removal from bone during remodeling.Fecal and urinary losses of 45Ca were continuous over a 16-day period and represented approximately 10% (5% in feces, 5% in urine) of the amount injected.The similarity of 45Ca uptake by the nasal turbinate and by the growth plates of long bones suggests that areas of active bone growth in different parts of the skeleton of the pig have similar turnover rates. The nasal turbinate, a tubular cancellous bone, may, therefore, be more susceptible to excessive resorption than the long bone as an organeven though no more susceptile than the growth plate of long bones as a tissue.

SELENIUM-VITAMIN E deficiency among growing pigs fed corn-soybean meal diets has been observed in commercial swine enterprizes in some areas of Midwestern and Eastern United States in recent years. These observations have provided the impetus for research related to selenium and vitamin E supplementation of diets for growing swine (Conrad et al.,1969; Wastell and Ewan, 1969; Ewan et al.,1969; Klein et al.,1970; Groce, et al.,1970). Kornegay (1971), Ullrey (1970) and Trapp et al.(1970) reviewed the vitamin E-selenium nutrition of swine and aspects of the field problem.Areas of the U. S. where the syndrome has become a problem have low soil levels and, in turn, low plant levels of selenium (Kubota et al.,1967). It has been suggested that heat-drying of corn may reduce its vitamin E content and thereby increase the incidence of vitamin E-Se deficiency in pigs. Sharp, Young and Van Dreumel (1970) reported a decrease in vitamin E activity of corn or complete diet by heating, but the decrease was not associated with survival rate of pigs.

Yorkshire pigs weaned at 3 to 5 weeks of age, weighing an average of 7.2 kg initially in experiment 1 and 4.9 kg in experiment 2, were pair-fed 3% protein purified diets containing 5 or 25% corn oil. The daily feed intake of the member of each pair fed the low fat diet was equalized with the ad libitum consumption of its mate fed the high fat diet. The total calorie consumption per pig was approximately 29% greater in the high fat group than in the low fat group. A similar diet containing 24% protein was fed as a positive control diet at a level of 4.5% of body weight daily in experiment 1 and 4.0% in experiment 2. Total serum protein level and percentage of albumin decreased significantly (P< 0.01) after feeding the low protein diets for 8 weeks. Pigs fed the low protein-high fat diet showed a more severe depression in serum proteins than those fed the low protein-low fat diet even though protein intake was equal for the 2 groups. Liver lipid concentration was 34.1% in the pigs fed low protein-high fat as compared with 9.7% in those fed low protein-low fat and 12.3% in positive control pigs. Pigs in the former group developed typical kwashiorkor-like symptoms, including severe edema in the umbilical and genital regions and general feebleness and apathy. In contrast, pair-fed mates fed the low protein-low fat diet failed to develop these symptoms and remained thin in appearance and active, indicating 2 different manifestations of protein deficiency, one resembling kwashiorkor, the other marasmus. Gross energy concentration of whole empty bodies of pigs fed the 2 low protein diets was similar (6.5 vs. 6.2 kcal/g of dry sample) but that of positive control pigs was significantly lower (P< 0.01) (5.6 kcal/g). This similarity in energy storage in the 2 low protein groups, despite the 29% difference in calorie intake, indicates not only an increased specific dynamic effect with low protein diets, but an additional increase when greater calorie intake accompanies protein deficiency.

The effects of feeding diets containing no fat, 3% hydrogenated coconut oil (HCO) or graded levels (0.1, 0.5, 1.0 or 3%) of safflower oil (SO) on serum cholesterol, lipids and protein level; on total heart and liver cholesterol and lipid level and on growth rate and skin condition were studied in weanling Yorkshire and Yorkshire × Hampshire pigs. Pigs fed the fat-free diet for 21 weeks developed severe skin lesions not observed in pigs fed HCO diets. Highly significant elevation of serum, liver and heart lipid and liver cholesterol, and a highly significant depression of total serum protein were observed with the feeding of HCO or fat-free diets. Serum cholestrol was significantly increased by HCO as compared with the fat-free diet or diets containing SO during the repletion period. Total heart cholesterol, growth rate and erythrocyte fragility were unaffected by diets. It is concluded that growth rate is not adversely affected in the pig by fat-free diets and that HCO does not produce skin lesions in the pig characteristic of fatty acid deficiency. Of all the correlation coefficients analyzed, only the serum cholesterol and total serum lipids were consistently highly significantly correlated, while serum protein was significantly inversely related to the total liver lipid.

Ten female and 230 male kits were used to study the need for pantothenic acid by growing mink. Three trials were conducted using purified diets with ad libitum and equalized paired-feeding techniques. The minimal pantothenic requirement for growth was found to be 5 mg of calcium pantothenate/kg of diet, whereas 8 mg/kg of diet were required for optimal performance. Anorexia and reduced serum cholesterol were early responses to hypovitaminosis. The gross pathological findings were diarrhea, cachexia, and dehydration with hemorrhagic gastric ulcers and specific starvation lesions.

Poor growth, mortality and myopathies of the heart and gizzard have been produced experimentally in young poults fed a practical-type diet containing all nutrients previously shown to be required by the poult except for supplemental vitamin E and methionine. The corn and soybean meal used in this diet were obtained from geographical areas where the soil is known to be low in selenium. Addition of vitamin E and methionine to the diet improved growth but gizzard myopathy was not prevented and maximal growth was not achieved until the diet also was supplemented with at least 0.1 ppm of selenium as sodium selenite. Under the conditions of these experiments, therefore, the selenium requirement in a practical-type diet depended to some extent upon the amount of vitamin E or methionine supplementation; it ranged from approximately 0.18 ppm in the presence of vitamin E to approximately 0.28 ppm of selenium in the absence of added vitamin E. Although myopathy of the skeletal (pectoral) muscle was not observed grossly, necropsy studies revealed histological changes in skeletal muscle typical of Zenker's degeneration. The order of prominence of the “selenium-responsive” diseases of the young poult appear to be: myopathy, first of the smooth muscle (gizzard); second, of the myocardium; and third, of the skeletal muscle. Selenium appears to be the primary nutritional factor required. Vitamin E is of less importance and sulfur amino acids are completely ineffective in prevention of these myopathies in poults.

A combined protein-vitamin E deficiency syndrome causing severe liver damage in the pig was studied by manipulating dietary levels of methionine, choline and selenium. Yorkshire pigs weaned at 3 weeks of age, weighing an average of 5 kg, were used in 4 experiments. During the 8-week experimental period the animals were fed a basal diet containing 3% isolated soy protein and 25% corn oil; it was marginal in vitamin E and selenium but adequate in all other nutrients. Consumption of this diet resulted in the development of liver necrosis which was most obvious histologically at weeks 2 and 4; at week 8 severe postnecrotic scarring of the liver predominated with little evidence of acute necrosis. The liver damage was completely preventable by supplementation with α-tocopherol, or selenium, or both. Choline supplementation aggravated the liver damage; however, methionine supplementation provided considerable, and in some cases, complete protection against necrosis and scarring but did not prevent the appearance of hyaline bodies in the hepatocytes. The methionine effect was not related to contamination of the supplemental methionine with selenium.

Intracellular mineral crystals were observed in cell cultures infected with one or more feline viruses. One was a feline syncytium-forming virus, and the other was a new feline virus which produced intranuclear inclusions in cell cultures. Crystals were noted both in autogenous cell cultures from trypsinization of kidneys and urinary bladders of infected cats (three passages) and in subcultures of culture fluids from these, made in a stable feline kidney cell line. Free mineral crystals were also noted in the fluids of the cell cultures. In two bladder and two kidney infected autogenous cultures, structures resembling the urinary calculi observed in obstructed cats were seen. These consisted of mineral crystals in a matrix of cellular debris.