Plasma vitamin E and other analyte levels in Nepalese camp elephants (Elephas maximus)

Plasma concentrations of alpha-tocopherol (vitamin E) and other analytes in Asian elephants (Elephas maximus) in Nepal were determined during typical work camp management of the elephants. Elephants foraged for food for 4-6 hr each day under the control of mahouts and were also provided daily with cut forage and supplements of unhusked rice, cane molasses, and salt. Blood samples were taken monthly for 1 yr without chemical restraint from 26 female elephants in four camps. Elephants were 6-60+ yr of age. Mean (+/-SEM) alpha-tocopherol concentration was 0.77+/-0.047 microg/ml, with a range of 0.23-1.57 microg/ml. Subadults had lower concentrations than did older elephants, and there were significant differences in mean concentrations from different camps and in mean monthly concentrations. Plasma alpha-tocopherol concentration appears to vary widely between individuals, and a single value of <0.3 microg/ml is not sufficient to diagnose incipient vitamin E deficiency. Mean (+/-SEM) plasma retinol (vitamin A) concentration was 0.063+/-0.003 microg/ml with a range of 0.01-0.12 microg/ml. Subadults had higher concentrations than did older elephants, and mean retinal values differed significantly among camps. Beta-carotene was not found in plasma. Twenty-five other analytes determined or derived were generally similar to those reported in other Asian and African (Loxodonta africana) elephants. Estimates of nutrient intake, based upon diet composition, suggested that dietary concentrations of zinc and sodium may have been marginal, but the absence of signs of any nutrient deficiencies indicates that dietary husbandry in these elephant camps was generally satisfactory.

Dietary fiber influences nutrient utilization, growth and dry matter intake of green iguanas (Iguana iguana)

Herbivory is an uncommon feeding strategy in lizards. Appropriate diet formulations for captive lizards should be based on performance measures, yet few data are available on the effect of plant fiber on food intake, nutrient utilization and growth of captive herbivorous lizards. This study was conducted to determine the effect of three levels of dietary fiber on dry matter intake, nutrient and energy metabolizability and growth rate of the green iguana (Iguana iguana). Twenty-one captive iguanas were fed nutritionally complete diets containing three levels of dietary fiber: 19, 24, and 27% neutral detergent fiber. The iguanas were fed each diet for at least 12 wk, and total excreta were collected for 11.3 +/- 4.0 d (means +/- , range of 7 to 25 d). Diets and excreta were analyzed for dry matter, organic matter, gross energy, neutral detergent fiber, acid detergent fiber, and acid detergent lignin. The study was designed as a Latin square crossover. Across all diets, dry matter intake was proportional to body mass1.0 (BM). Growth rate was greater (P < 0. 05) when iguanas were fed the low and medium fiber diets (2.2 and 2. 4 g/d, respectively) than when fed the high fiber diet (1.4 g/d). However, mean daily dry matter intake of the three diets [7.2 g/(d. kg BM)] was not different. In general, digestibility of fiber fractions and the metabolizability of dietary energy decreased (P < 0.05) as the level of dietary fiber increased. These data suggest that a diet containing less than 27% neutral detergent fiber should be fed if rapid growth is to be sustained during intensive captive production of green iguanas.

Calcium level affects the efficacy of supplemental microbial phytase in corn-soybean meal diets of weanling pigs

A 2 x 2 x 2 factorial experiment was conducted with 64 pigs (4 wk old, 8.04 +/- .50 kg BW) to determine the effect of various dietary concentrations of Ca, vitamin D, and microbial phytase (Aspergillus niger) on phytate-P utilization. A low-P, corn-soybean meal diet was supplemented with two levels of phytase (unit/gram), 750 (suboptimal) and 1,200 (optimal); of vitamin D (international unit/kilogram), 660 (normal) and 6,660 (high); and of Ca (percentage), .4 (low) and .8 (normal). Pen feed consumption and individual pig weights, plasma inorganic P and Ca concentrations, and plasma alkaline phosphatase (AP) activity were measured at d 10, 20, and 30. The normal dietary Ca concentration had an adverse effect (P < .05) on all the response measures. The depressive effect of the normal dietary Ca on performance was greater (P < .05) at the normal vitamin D level or at the optimal phytase level than at the other levels of these two factors. The elevation in plasma AP activity in pigs fed the normal dietary Ca was greater (P < .05) at the suboptimal than at the optimal phytase level. The decreases in plasma inorganic P concentration and increases in plasma Ca concentration associated with the normal dietary Ca were substantial. In conclusion, the normal level of Ca in the diet greatly reduced the efficacy of supplemental phytase. Raising vitamin D in the diet partially offset this adverse effect but did not produce further improvement when the Ca level was low.

Supplementing corn-soybean meal diets with microbial phytase maximizes phytate phosphorus utilization by weanling pigs

Two experiments were conducted with crossbred weanling pigs to determine the optimal dietary supplement of Aspergillus niger phytase activity to a low-P, corn-soybean meal basal diet (BD). In Exp. 1, 50 pigs (7.61 +/- .56 kg BW) received the BD supplemented with 750, 1,050, 1,250, or 1,350 phytase units (PU)/g, or .21% P as mono-dibasic calcium phosphate (MDCaP) for 4 wk. In Exp. 2, 12 pigs (6.39 +/- .74 kg BW) were individually housed in metabolism cages and received BD, BD plus the optimal phytase activity (1,200 PU/g), or BD plus .21% P as MDCaP for 2 wk. In Exp. 1, additions of phytase > 1,050 PU/g of BD did not improve ADG, ADFI, gain/feed, or plasma AP activity. Quadratic relationships between dietary phytase activity and these measures were found and their stationary points were at approximately 1,200 PU/g of BD. Estimated maximum responses of these measures in pigs fed phytase were > or = 90% compared with MDCaP. Pigs fed 1,250 PU/g of BD maintained normal plasma P and Ca concentrations. In Exp. 2, pigs that received 1,200 PU/g of BD utilized dietary P more effectively (P < .05) than pigs fed the BD or the BD plus MDCaP. Although they consumed 44% less P per day, these pigs retained only 7% less P than pigs that received MDCaP. One thousand units of phytase activity supported retention of 1.1 mg of P from the BD, and this level of phytase supplementation was equivalent in effect to .91 mg of P from MDCaP.(ABSTRACT TRUNCATED AT 250 WORDS)

Supplemental microbial phytase improves bioavailability of dietary zinc to weanling pigs

Two experiments were conducted to determine the effects of supplemental microbial phytase on utilization of dietary zinc by weanling pigs. Experiment 1 was a 2 x 3 factorial arrangement of treatments with 24 pigs for 4 wk. Two levels of phytase activity (0 and 1350 units/g) and three levels of zinc (0, 30 and 60 mg/kg as ZnSO4.7H2O) were added to a corn-soybean meal basal diet. Weekly measures included growth performance, plasma alkaline phosphatase activity and plasma mineral concentrations. In Experiment 2, mineral balances were determined in 12 pigs fed the basal diet or the diet with added zinc (30 mg/kg) or phytase (1350 units/g). The results indicated that either supplemental phytase or supplemental zinc increased plasma alkaline phosphatase activity and plasma zinc concentrations, but these increases were not additive. Supplemental phytase decreased plasma alkaline phosphatase activity in pigs supplemented with zinc. Supplemental phytase also significantly enhanced weight gain, feed intake, gain:feed ratio, plasma concentrations of inorganic phosphorus, and retention of phosphorus and calcium. Neither supplemental phytase nor zinc affected zinc retention. Supplementing corn-soybean meal diets with microbial phytase at 1350 units/g feed improves bioavailability of zinc as well as of phytate phosphorus to weanling pigs.

Basis for regulation of selenium supplements in animal diets

Selenium was discovered 174 yr ago but, until 1957, was given little notice by biologists or was vilified as an agent that caused toxicity in grazing ruminants and horses in the northern Great Plains. After its status as an essential nutrient was established, Se received intense scrutiny, and hundreds of papers have been published dealing with its metabolic functions and the consequences of a Se deficiency. Because regions of Se deficiency are so extensive in the United States, great efforts have been made to gain Food and Drug Administration (FDA) approval for Se supplementation of animal diets. Initially, these efforts were thwarted by concern that Se might be carcinogenic. After this concern was resolved, researchers established supplemental Se levels that were efficacious, safe for animals, safe for humans that eat animal products, and protective of the environment. First approval of Se supplements was given in 1974 for supplementation of swine or growing chicken diets at .1 ppm. Supplements for turkey diets were approved at .2 ppm. Ultimately, in 1987, levels of supplemental Se in diets for chickens, turkeys, ducks, swine, sheep, and cattle were approved at .3 ppm. However, FDA regulations do not mention horses or zoo animals, and those who would ensure the welfare of these species by supplementing Se-deficient diets may be in violation of FDA interpretation of the law. In addition, the association of Se with death and deformities in aquatic birds at the Kesterson Reservoir in California has led to pressure on the FDA to reverse the 1987 amendments to the feed additive regulation.(ABSTRACT TRUNCATED AT 250 WORDS)

Dietary selenate versus selenite for cattle, sheep, and horses

Food and Drug Administration regulations currently permit addition of .3 mg of Se per kilogram of diet for chickens, turkeys, ducks, swine, sheep, and cattle. However, field reports indicate that this level may not be adequate for ruminants in all situations. Because sodium selenite is the most common supplemental form and is known to be readily absorbed to particles or reduced to insoluble elemental Se or selenides in acid, anaerobic environments, studies were conducted with dairy cattle, sheep, and horses fed sodium selenate to determine whether Se from this source was more bioavailable than Se from sodium selenite. A 2-wk period of no Se supplementation was followed by 49 or 56 d of Se supplementation at .3 mg/kg of dietary DM. Serum Se concentrations and glutathione peroxidase (GSHPx) activities measured initially and periodically thereafter revealed no difference between Se forms in sheep and horses and only a small (P less than .05) advantage for selenate in supporting serum Se concentration in dairy cattle. Selenium concentrations in skeletal muscle and liver of sheep were not different between Se forms. Serum Se, but not GSHPx, increased with time, and .3 mg of supplemental Se per kilogram of dietary DM from either sodium selenate or sodium selenite supported normal serum Se concentrations in sheep, dairy cattle, and horses.

Formulated diets versus seed mixtures for psittacines

Psittacines are often classified as seed eaters despite studies that have established great diversity in food habits in the wild. While seeds are consumed, so are flowers, buds, leaves, fruits and cambium. Some psittacines consume part of greater than 80 species of grasses, forbs, shrubs and trees. In addition, insects may be important. Although there are few controlled studies of the requirements of psittacines, it is probable that most nutrient needs are comparable to those of domesticated precocial birds that have been thoroughly studied. Commercial seed mixes for psittacines commonly contain corn, sunflower, safflower, pumpkin and squash seeds, wheat, peanuts, millet, oat groats and buckwheat, although other seeds may be present. Because hulls/shells comprise 18-69% of these seeds and they are removed before swallowing, a significant proportion of typical seed mixtures is waste. Some of the seeds also are very high in fat and promote obesity. Common nutrient deficiencies of decorticated seeds include lysine, calcium, available phosphorus, sodium, manganese, zinc, iron, iodine, selenium, vitamins A, D, E and K, riboflavin, pantothenic acid, available niacin, vitamin B-12 and choline. Attempts to correct these deficiencies by incorporating pellets into seed mixes are usually thwarted by rejection of the pellets and disproportionate consumption of items that are more highly favored. An extruded diet formulated to meet the projected nutrient needs of psittacines was fed with fruits and vegetables to eight species of psittacines for 1 y. Fledging percentage was increased to 90% from the 66% observed during the previous 2 y when these psittacines were fed seeds, fruits and vegetables. Although this extruded diet was well accepted in a mixture of fruits and vegetables and met nutrient needs, analyses have shown that not all commercial formulated diets are of equal merit.

Relationship between body fat and postweaning interval to estrus in primiparous sows

Twenty-two primiparous Yorkshire sows were used to determine whether a minimal threshold of body fat exists below which the return to estrus is delayed. A second objective was to examine the relationship between body fat and interval from weaning to estrus in restricted-fed sows. During lactation (28 d), sows received 7, 9, 11 or 13 Mcal of ME daily to produce a range of sow body fatness at weaning. Intake of all dietary essentials except ME was similar for all sows. Litter size was adjusted to 10 pigs for all sows by d 3 postpartum. Each day from weaning to estrus, sows received 110 kcal ME per kg metabolic body weight plus 1,359 kcal ME per sow. Body fat was estimated at weaning and at first postweaning estrus by deuterium oxide dilution. Last rib backfat depth was determined ultrasonically 24 h postpartum and at weaning. Irrespective of dietary ME intake, percentage body fat at weaning (R2 = .24; P less than .05) and first postweaning estrus (R2 = .03; P greater than .50) accounted for only a small portion of variation in interval from weaning to estrus. Likewise, loss of backfat depth during lactation was not an accurate predictor of interval from weaning to estrus (R2 = .24; P less than .05). The low coefficients of determination (less than .25) suggest that body fat is a minor controller of postweaning interval to estrus. In contrast, dietary ME intake during lactation accounted for the largest portion of the variation (R2; = .48; P less than .01) in postweaning interval to estrus. We conclude that timing of postweaning estrus in primiparous sows is not dependent on a minimal threshold of body fat. Furthermore, effects of lactational ME intake on the postweaning interval to estrus are more pronounced than the effects of body fat.

Bioavailability of beta-carotene in humans

Normal healthy volunteers were studied after they ingested various beta-carotene doses. Daily administration of 15 or 45 mg beta-carotene resulted in significant increase in plasma beta-carotene levels. The extent of increase and the pattern of plasma beta-carotene levels showed substantial interindividual variation. Absorption of beta-carotene was affected by dietary fat concentration. Individuals placed on a high-fat diet showed significant increases in plasma beta-carotene as compared with those placed on a low-fat diet. Pharmacological doses of beta-carotene (45 and 90 mg) were used in intermittent schedules (5-6 d intervals) without altering the steady state of beta-carotene plasma levels. Yellowing of the skin occasionally occurred during daily dosing with 45 mg beta-carotene without evidence of toxicity. The observed individual variation in bioavailability of beta-carotene raises questions regarding clinical use of this micronutrient. It appears that determination of target plasma beta-carotene concentrations is essential for effective use of this compound in prevention or treatment.

Responses of dairy cattle to long-term and short-term supplementation with oral selenium and vitamin E1

In a two-lactation-gestation cycle experiment, 152 Holstein cows with low serum Se and vitamin E were fed total mixed rations and assigned at parturition to four groups (1, control; 2, 500 IU vitamin E/d; 3, 2 mg Se/d; 4, 500 IU vitamin E plus 2 mg Se/d). Supplements were not fed during dry periods. Serum Se and vitamin E were increased within 1 mo by oral supplements. Maximal mean serum Se in cycles 1 (67 ng/ml at 7 mo) and 2 (74 ng/ml at 4 mo) occurred in groups 3 and 4, respectively. Maximal mean serum vitamin E in cycle 1 (3.3 micrograms/ml at mo 8) and 2 (3.03 micrograms/ml at mo 2) occurred in groups 4 and 2, respectively. Selenium treatment of the dams increased Se in colostrum and in serum of presuckle calves. Vitamin E supplementation of dams did not affect vitamin E in serum of presuckled calves. Reproductive performance was not affected by supplement. In an 8-wk study, 24 lactating cows with low serum Se were assigned (6/group) to 0, 2.5, 5, and 10 mg supplemental Se/d. Maximal mean serum Se concentrations of 23, 56, 71, and 79 ng/ml were attained by wk 4 in the above respective groups. These data indicate that 2 to 2.5 mg supplemental Se/cow per d were inadequate for desirable serum Se concentrations and support recent changes in allowed Se supplementation for dairy cattle.

Biochemical and physiological indicators of selenium status in animals

Selenium (Se) concentrations in animal tissues vary with the tissue and with the amount and chemical form of Se in the diet. In cattle, sheep and swine, Se concentrations rank in kidney greater than liver greater than heart greater than skeletal muscle greater than adipose tissue. Selenium concentrations (wet basis) in skeletal muscle of swine (.03 to .52 ppm) reflect natural dietary Se concentrations ranging from .03 to .49 ppm. Inorganic Se additions to diets low in natural Se (.05 ppm) increase skeletal muscle Se concentrations until dietary Se levels are adequate. After a period of Se repletion, skeletal muscle Se concentrations should be at least .08 ppm on a wet basis. Selenium concentrations in plasma, serum or whole blood are also related to inorganic Se intake and rise in direct relation to each other in the deficient to adequate range. Plasma or serum Se concentrations of .08 to .12 ppm are consistent with dietary adequacy. Selenium-dependent glutathione peroxidase (GSH-Px) activity of plasma or whole blood may also be used to assess Se status in some animals since plasma or whole blood Se concentrations are positively correlated with GSH-Px activity in animals that are low to adequate in dietary inorganic Se. However, inter-laboratory variation in GSH-Px values is large, and it is doubtful that limits of normalcy developed in one laboratory are applicable in others. In certain tissues it is important to distinguish between GSH-Px and glutathione (GSH) S-transferases, which can reduce organic hydroperoxides but which are not Se-dependent. It is also important that the instability of GSH-Px be considered so that losses in activity during handling and storage may be minimized. Urinary Se excretion and Se retention as percentages of Se intake may be helpful in assessing Se status when facilities for metabolism studies are available.

Plasma vitamin and mineral status in home parenteral nutrition patients

Home parenteral nutrition (HPN) provides long-term nutritional support for persons whose absorptive capacity is compromised by a variety of intestinal malabsorption problems. However, the presence of vitamin and mineral deficiency syndromes that normally would not have time to develop in the hospitalized patient receiving total parenteral nutrition has been reported in patients receiving HPN. This study entails a longitudinal survey of plasma concentrations of vitamins A, E, and 1,25-dihydroxyvitamin D, as well as the minerals zinc, copper, and selenium, in patients receiving HPN. Plasma samples from eight patients who had been on HPN for 1-92 months before the study began were obtained once a month over a 12-month period. The blood was drawn immediately before their evening infusion of TPN in order to approximate fasting plasma nutrient concentrations. Patient values were compared to fasting control values and to published norms. Values for vitamin A, 1,25-dihydroxyvitamin D, and zinc all were within the normal range, and there was no evidence of metabolic bone disease. Plasma vitamin E and copper concentrations exceeded the normal range for most of the 12-month period. Of all of the nutrients studied, only plasma selenium concentrations were consistently in the low-normal to below-normal range. Selenium levels in patients on HPN should be monitored regularly, and supplementation may be necessary if clinical conditions warrant.

Abrogation of adriamycin-induced cardiotoxicity by selenium in rabbits

Adriamycin-induced cardiomyopathy in rabbits was produced by intravenous injections of the drug with a short therapeutic schedule (3 mg/kg body wt administered as four intermittent doses). Animals receiving selenium supplementation of Adriamycin showed preservation of the normal pattern of the heart histologic picture. The protective effect of selenium was accompanied by increased selenium levels in the plasma and the heart muscle. An eventual interaction between the antitumor effect of Adriamycin and the protective effect of selenium was ruled out by in vitro experiments using the L1210 cell line. Selenium did not abrogate the antiproliferative effect of Adriamycin when the cells were treated simultaneously with both agents. The results from this study indicate that Adriamycin-induced cardiotoxicity could be prevented by selenium if the animals were pretreated with selenium, rather than simultaneous administration of both agents. The mechanism of this effect is not entirely understood.

Body composition of white-tailed deer estimated by deuterium oxide dilution

Nine nonpregnant, female white-tailed deer (Odocoileus virginianus), 2 to 4 years of age, were used to determine whether body composition can be estimated from deuterium oxide dilution in body water. Venous blood was collected at 0, 20, 30, 40, 50, 60, 80, 120, 240, and 480 min and at 24 and 48 h after deuterium oxide infusion. The deer were then killed and analyzed for dry matter, crude protein, ether extract, and ash. Deuterium oxide dilution, extrapolated to zero time, overestimated analyzed body water by 6%, but the two measures were highly correlated (r2 = 0.85). Incorporation of live weight with estimated body water in the prediction equation increased r2 to 0.95. Ingesta-free body crude protein and ether extract were highly predictable (r2 = 0.92 and 0.96, respectively) from live weight (WT) and estimated total body water (ETBW). The prediction equation for ingesta-free body ether extract was EE = −7.520 + 0.6110(WT) – 0.5417(ETBW), with all measures expressed in kilograms. When ETBW was determined from deuterium oxide dilution in a single 2-h postinfusion blood sample, the prediction equation for ingesta-free body ether extract was EE = −6.306 + 0.6977(WT) – 0.6870(ETBW) (r2 = 0.94).

Importance of diet of dam and colostrum to the biological antioxidant status and parenteral iron tolerance of the pig

Fifteen second-parity sows were used to determine the importance of vitamin E (E) and selenium (Se) supplementation of the sow's diet and colostrum consumption by the neonatal pig on tolerance to parenteral iron. Selenium (.1 ppm) and E (50 IU/kg) supplementation of the diet of the sow increased plasma tocopherol and Se concentrations, but did not increase plasma glutathione peroxidase (GSH-Px) activity. Colostrum had greater concentrations of E (primarily alpha-tocopherol) and Se than milk. Plasma biological antioxidant status (tocopherol level and GSH-Px activity) of pigs at birth was very low, but by 2 d of age had increased, especially in alpha-tocopherol (nearly a 20-fold increase). Liveability and body weight gain of pigs were not affected by the pre-colostrum iron injection (200 mg Fe as gleptoferron); however, plasma tocopherol concentrations of Fe-injected pigs were lower and plasma Se concentration and GSH-Px activities were higher at 2 d of age than values of pigs not receiving parenteral Fe. Supplementation of the dam's diet with E and Se maintained high tocopherol and Se levels in her colostrum and milk and a high biological antioxidant status in her pigs throughout the nursing period.

Stability of glutathione peroxidase in swine plasma samples under various storage conditions

The stability of plasma glutathione peroxidase under different temperatures (4 degrees C vs. -15 degrees C), various durations of storage (0, 1, 2, 3, 7, 14, 28 and 56 d), and storage under inert gas (nitrogen (N2)) vs air is described. The glutathione peroxidase activity of swine plasma decreased consistently with storage at either 4 degrees C or -15 degrees C 1-56 d after collection, and differed (P less than or equal to 0.01) from the initial values. Storage under N2 at -15 degrees C slowed the rate of enzyme activity decrease but did not maintain the initial activity. For absolute measurements, it is suggested that swine plasma glutathione peroxidase activity be measured immediately after separation from the blood cells or be assayed within 24 h in plasma samples stored at -15 degrees C with air space displaced by N2. If relative treatment differences in enzyme activity are satisfactory, then assays can be conducted after controlled periods of storage.

Effects of riboflavin supplementation and selenium source on selenium metabolism in the young pig

The effect of dietary riboflavin (B2) supplementation and selenium (Se) source on the performance and Se metabolism of weanling pigs was studied. Pigs fed a B2-supplemented (10 mg/kg) casein-glucose diet for 18 d gained faster than pigs fed the B2-unsupplemented diet. Percentage active erythrocyte glutathione reductase (GR) declined rapidly when pigs were placed on the B2-unsupplemented diet and was lower (P less than .01) than that of B2-supplemented pigs after 12 d on test. Percentage active erythrocyte GR values fell below 50% before other B2 deficiency signs became evident. Supplementation of diets with 10 mg B2/kg resulted in increased kidney and muscle glutathione peroxidase (GSH-Px) activity. The Se concentration of liver and heart increased and plasma Se levels decreased with dietary B2 supplementation. Riboflavin supplementation and Se source did not alter apparent Se absorption, but B2 supplementation decreased urinary Se and thus increased Se retention. Also, there was less urinary Se excretion when selenomethionine was the dietary Se source and consequently more Se was retained than when sodium selenite was the dietary Se source. In a final trial, B2 supplementation increased kidney, muscle, heart and brain GSH-Px activity when sodium selenite was the dietary Se source, but not when selenomethionine was the dietary Se source.

Blue-green color and composition of Stejneger's beaked whale (Mesoplodon stejnegeri) milk

Two hundred ml of milk were obtained from a lactating Stejneger's beaked whale stranded at Ninilchik, Alaska on 21 Oct, 1980. Total solids (41%) were similar to values reported for sperm and belukha whales, while fat (17%) was half as great and crude protein (17%) was 2-4 times greater than in milk of these species. Lactose was not detected. Calcium (0.22%) was greater than reported for pigmy sperm whales but less than for blue whales. Phosphorus (0.07%) was less than for any of the above species. Sodium and potassium concentrations were 0.13% and 0.11%, respectively. Values (microgram/g) for other elements analyzed (magnesium, 42; iron, 35; copper, 2.6; zinc, 1.5; manganese, 0.3; selenium, 0.36) have not been reported for whale milk. Based on SDS-gel electropherograms, this whale milk did not contain a whey protein corresponding to cattle milk alpha-lactalbumin. A blue-green pigment in the milk was identified as biliverdin.

Effect of parenteral iron on serum electrolytes of the baby pig

Twenty-eight 4-d-old nursing pigs were used in two trials to evaluate the effects of im injection of iron (Fe) from Fe-dextran upon subsequent serum mineral concentrations. An im injection of 150 mg of Fe from Fe-dextran was given to all pigs (n = 17) in trial 1. Serum Fe concentration increased rapidly from an initial mean of 65 to 3,466 micrograms/dl at 6 h postinjection (PI), 5,712 micrograms/dl at 24 h PI, then fell to 317 micrograms/dl at 4 d PI, 143 micrograms/dl at 7 d PI and remained about 100 micrograms/dl at 14, 21 and 28 d PI. Concentrations of other serum minerals did not appear to be influenced by the Fe-dextran injection. Treatments of Pigs (n = 11) in trial 2 were no injection, injection of dextran only, injection of 100 mg Fe from Fe-dextran and injection of 200 mg Fe from Fe-dextran. Serum Fe concentration increased rapidly after Fe-dextran injection, rising to a peak of 11,028 micrograms/dl at 6 h PI from the 100-mg Fe injection and 17,012 micrograms/dl at 6 h PI from the 200-mg Fe injection. Serum Fe concentration dropped steadily in pigs that were given no injection or injected with dextran only. Seven days after trial 2 started, all pigs that had received no injection or dextran only were injected with 100 mg Fe from Fe-dextran.(ABSTRACT TRUNCATED AT 250 WORDS)

Concentration of minerals in tissues of pigs from dams fed different levels of dietary zinc

Effects on the tissue mineral concentrations of pigs from sows fed four dietary Zn levels were studied. A male and a female from first- and second-parity litters were killed at 1 and 21 d of age. The dams were fed a corn-soybean meal basal diet supplemented with 0, 50, 500 or 5,000 ppm Zn from 30 kg body weight until completion of the second lactation. Pigs from sows fed 5,000 ppm additional zinc had heavier liver, heart, thyroid and adrenal weights relative to their body weight than did pigs from sows on the other treatments. First- and second-parity pigs from sows on the highest Zn supplementation level had higher Fe stores in the liver, higher Zn concentrations in the liver, kidney and pancrease, and higher Cu levels in the kidney compared with pigs from sows on the other treatments. However, Cu concentrations in the liver, heart, pancreas, esophagus, aorta and testes were reduced in pigs from sows on the 5,000 ppm Zn treatment. In first-parity pigs, Ca in the liver was higher for pigs whose dams received 5,000 ppm Zn compared with pigs from sows on all other treatments, and the Mn level was higher compared with pigs from sows receiving 50 or 500 ppm additional zinc. Pigs at 1 d of age from sows on the 0, 50 or 500 ppm treatment had lower hepatic P and Zn concentrations than pigs from sows on the same treatment at 21 d of age. The reverse was true for pigs whose dams received 5,000 ppm Zn.

Thyroid iodine and serum thyroid hormone levels in wild white-tailed deer (Odocoileus virginianus) from central Michigan

Three wild, female white-tailed deer (Odocoileus virginianus) collected in Missaukee County, Michigan, during February and March 1979 had lower (P < 0.01) serum total thyroxine (T4), free T4 (FT4), and triiodothyronine (T3) levels, thyroid iodine (I) concentration, and body weights than 17 captive does fed a complete diet. Thyroid weight per metabolic body weight (body weight (kilograms)0.75) was greater (P < 0.01) in the wild deer. These data indicate malnutrition and incipient I deficiency in the wild deer.

A copper deficiency in neonatal pigs induced by a high zinc maternal diet

Because high levels of dietary zinc are known to reduce copper body stores, the objective was to determine if a high zinc maternal diet could induce a copper deficiency in the newborn pig fed a dried skim milk--glucose--starch diet unsupplemented with copper. The offspring of gilts, which were fed 5000 ppm of zinc, were allowed to nurse until 3 to 5 days of age when they were weaned and placed in individual stainless-steel pens. The dietary treatments were 0, 5 and 10 ppm added copper from copper sulfate. After 14 days, pigs receiving the 0-ppm copper diet weighed significantly less (P less than 0.05) and had reduced hemoglobin, hematocrit and serum copper concentrations and no detectable ceruloplasmin activity. After 5 weeks, the pigs were killed, and tissues were collected. The unsupplemented group had 16.4% of the aortic lysyl oxidase activity of the 5-ppm group. Cytochrome c oxidase activity in the heart and liver, and copper stores in the heart, liver, pancreas and kidney were depressed (P less than 0.05) in unsupplemented pigs compared to those receiving 5 ppm copper. These data demonstrate that it is possible to produce quickly a markedly copper-deficient pig, by using the offspring of sows fed 5000 ppm zinc, and support previous conclusions that the dietary copper requirement of the baby pig is about 5 ppm.

Thyroid function in fed and fasted white-tailed deer fawns

Serum thyroid hormone concentrations and thyroxine (T4) kinetics were determined in three fed and two fasted white-tailed deer fawns (Odocoileus virginianus borealis). Fasting for 16 days resulted in a drastic decline in total triiodothyronine (T3) (3.22 to 0.49 ng/mL), T4 (241.6 to 68.3 ng/mL) and, to a lesser extent, free T4 (FT4) (2.59 to 1.37 ng/dL). Reverse T3 (rT3) did not change significantly. Although T4 secretion rate (TSR) was greatly reduced (P < 0.05) in the fasted fawns (2.5 (fasted) versus 10.5 (fed) μg T4 per body weight 0.75 (in kilograms) after 20 days of fasting), fractional turnover rate (k/day), total distribution volume (TDV), and metabolic clearance rate (MCR) of injected [131I]T4 did not differ significantly from values in fed fawns. Serum thyroid hormone profiles of the fasted fawns were similar to those reported previously in wild deer collected in Michigan during late winter. In contrast, however, there was no indication of thyroid enlargement.

Iron requirements of baby pigs reared in germ-free or conventional environments on a condensed milk diet

Baby pigs were maintained in either a germ-free or a conventional environment and fed a sterile condensed milk diet (10 micrograms Fe/g milk solids) supplemented with 0, 50 or 100 micrograms Fe/g solids from FeSO4.7H2O or given an im injection of 100 mg Fe from Fe dextran. Pigs were reared on these diets for 4 wk, and weekly measures of gain, food consumption and hematology were taken. The pigs were then killed, and organ weights were taken and tissues analyzed for Fe concentration. All conventional pigs not given supplemental Fe died. None of the unsupplemented pigs raised in the germ-free environmental died. Conventional pigs gained faster and more efficiently and became anemic more rapidly. However, conventional and germ-free pigs were similar in the efficiency with which they incorporated supplemental Fe into hemoglobin or stored Fe in liver and spleen. We concluded from this study that both germ-free and conventional pigs fed a condensed milk diet require 50 to 100 micrograms Fe/g milk solids or more than 100 mg of Fe from Fe dextran once parenterally to maintain desirable hematological traits for 4 wk.

Bioavailability of iron from ferric choline citrate and a ferric copper cobalt choline citrate complex for young pigs

Two experiments were conducted to determine the bioavailability for young pigs of Fe from ferric choline citrate or from a commercial mixture of Fe, Cu and Co choline citrate salts. Relative biological value of Fe from either source with a standard of 100 for FeSO4 x 7H20 was about 140 by both hemoglobin regeneration and Fe retention methods.

Eucalyptus Digestibility and Digestible Energy Requirements of Adult Male Koalas, Phascolarctos Cinereus (Marsupialia)

Three adult male koalas were individually fed on a diet of Eucalyptus melliodora, E. robusta and E. sideroxylon plus trace mineral salt and water to appetite. Fresh browse was offered daily for 14 days before and 7 days during quantitative collection of faeces. Samples of browse representing plant parts consumed were collected, and acid lignin ratio techniques were used to estimate nutrient digestibility. Apparent digestibility of DM was 54-70%, gross energy 47-64%, crude protein 32-50%, ether extract 37-50%, neutral detergent fibre 23-57% and acid detergent fibre 9-55%. Total faecal acid lignin excretion was used to estimate digestible energy (DE) intake. Since bodyweights (W) were maintained during the study, daily DE requirements for adult maintenance were estimated to range from 257 to 411 kJ/W0.75. If an 87% recovery in the faeces of dietary acid lignin was assumed, estimated DE requirements for adult maintenance ranged from 312 to 439 kJ/W0.75. These values are lower than commonly accepted interspecific values for eutherians but are consistent with evidence that the koala has a relatively low basal metabolic rate.

Composition of Preferred and Rejected Eucalyptus Browse Offered to Captive Koalas, Phascolarctos Cinereus (Marsupialia)

Browse representing 1.5 m of terminal growth from 11 species of Eucalyptus shoots or mature tree limbs was divided into portions which were either consumed or rejected by captive koalas. The following nutrient concentrations (dry basis) were found in preferred browse: crude protein, 5.9-17.8%; ether extract, 5.5-19.2%; neutral detergent fibre, 16.8-37.5%; ash, 3.2-5.6%; remaining proximate fraction [(dry matter) - (crude protein + ether extract + neutral detergent fibre + ash)], 31.7-64.8%; calcium, 0.28-1.95%; phosphorus, 0.08-0.42%; sodium, 0.03-1.29%; potassium, 0.30-2.06%; magnesium, 0.12-0.44%; iron, 67-274 ppm; copper, 2.1-15.8 ppm; zinc, 17-54 ppm; and selenium, 0.03-0.42 ppm. Preferred browse, as compared to rejected browse, had significantly higher concentrations of crude protein, remaining proximate fraction, phosphorus and potassium, and significantly lower concentrations of ether extract, neutral detergent fibre, acid detergent fibre, permanganate lignin, gross energy, calcium, iron and selenium.

Regulation of essential nutrient additions to animal diets (selenium -- a model case)

Responsibility for regulation of essential nutrient additions to animal diets has been assumed by the Food and Drug Administration (FDA) through internal interpretation of the Federal Food, Drug and Cosmetic Act. Thus, these substances are regulated as food additives or through qualification for the generally recognized as safe (GRAS) list. Although essential nutrients, such as selenium, are not optional additives to animal diets that are demonstrably deficient (if animal health and welfare are of concern), supplementation with unapproved nutrients places one in violation of FDA interpretation of law. Selenium was established as a dietary essential in 1957, and practical problems with a deficiency of this nutrient were recognized soon after. Research was begun in 1967 specifically to gain FDA approval for selenium as a dietary supplement. Approval was granted for selenium supplements to swine and certain poultry diets in 1974. At that time, FDA staff members reported that the inability to supplement these diets with selenium had caused annual losses of over $82 million. Annual losses to the beef cattle, dairy cattle and sheep industry were estimated in 1975 at nearly $545 million. In a coordinated effort (initiated in 1975) involving scientists at nine United States universities and the FDA, data were gathered leading to approval in 1979 of selenium supplements for ruminants. The cost of the effort to meet regulatory requirements for selenium has been estimated at more than $1 million. Since this nutrient is not a proprietary product, this effort has been made largely at public expense. The inability to supplement selenium-deficient diets prior to FDA approval has cost hundreds of millions of dollars.

Regulation of animal care and research? Viewpoint of an agricultural experiment station scientist

The issue of regulating animal care in modern animal production systems and in the research laboratory is discussed from the perspective of an animal scientist with a farm background and 25 years of agricultural experiment station experience. Evidence is presented for a long-term association of humans with (and dependence on) animals, which extends into prehistory far beyond the beginnings of animal domestication some 11,000 years ago. The problem of feeding humans without animals was discussed, and it is concluded that the world population of humans cannot be adequately nourished by plant foods alone. Man's activities affect all of his companion creatures in many ways, and he is obviously a participant in a global ecosystem, not just an observer. It is vital to his welfare and to that of his fellow creatures that he manage this ecosystem fellow creatures that he manage this ecosystem correctly, including members of both the animal and vegetable kingdoms. There is a serious difference in perspective between many "animal philosophers" and professional animal scientists. The latter believe that they have an obligation to practice and to teach respect for the lives and welfare of the animals with which they work. Human qualities of kindness, mercy and compassion should govern actions toward animals. However, anthropomorphism is a philosophy to which the author and many other animal scientists do not subscribe.

Selenium, vitamin E and the response to swimming stress in the rat

Experiments were conducted to determine the effects of exercise on rat glutathione peroxidase system enzymes and lipid peroxidation among animals supplemented and unsupplemented with selenium (Se) and vitamin E (E). Liver, muscle and blood were taken before, immediately after and 24 hours after exercising to exhaustion by swimming. No effect of exercise was found on muscle or liver enzymes, although exercise resulted in depressed glutathione reductase (GR) and glucose-6-phosphate dehydrogenase (G6PD) activities in erythrocytes immediately after exercise. Dietary Se supplementation did result in increased hepatic muscle and erythrocyte glutathione peroxidase activity, and decreased hepatic GR, G6PD and "malic enzyme" activities. Thiobarbituric acid reactive substances, and indicator of lipid peroxidation, increased in liver and muscle subsequent to exercise. This increase was reduced in liver, but not eliminated, by dietary E supplementation. The increase was not affected by dietary E in muscle, nor by dietary Se in either tissue.

Copper requirement of baby pigs fed purified diets

Three experiments involving 52 baby pigs were conducted to determine the minimum copper requirement of baby pigs fed purified diets. Diets were supplemented with anhydrous cupric sulfate to yield the following copper concentrations (ppm, by analysis) when the three experiments were combined: 0.6, 0.9, 1.3, 1.9, 2.0, 2.8, 3.2, 4.0, 4.9, 5.6 and 9.3. Parameters examined include weight gain, hematocrit, hemoglobin concentration, mean corpuscular hemoglobin concentration, plasma ceruloplasmin activity, plasma copper concentration, copper balance, brain and erythrocyte superoxide dismutase activity, copper concentration of liver, kidney, spleen, heart, brain, femur and hair, liver ferritin-iron and total iron concentration, strength characteristics of the femur, and gross and histological appearance at necropsy. Weight gains were subnormal at dietary copper concentrations below 1.9 ppm; plasma ceruloplasmin activities, and plasma and tissue copper concentrations were depressed at dietary copper levels below 2.8 ppm. Bone histopathology was evident at dietary copper levels below 3.2 ppm, and copper balance was low at dietary copper levels below 4.9 ppm. Some evidence of anemia was present at dietary copper levels below 5.6 ppm. Under the conditions of this study, the copper requirement of the baby pig fed a purified diet was judged to be approximately 5.6 ppm (6 ppm copper, dry basis).