Recent Northern Hemisphere stratospheric HCl increase due to atmospheric circulation changes.

The abundance of chlorine in the Earth's atmosphere increased considerably during the 1970s to 1990s, following large emissions of anthropogenic long-lived chlorine-containing source gases, notably the chlorofluorocarbons. The chemical inertness of chlorofluorocarbons allows their transport and mixing throughout the troposphere on a global scale, before they reach the stratosphere where they release chlorine atoms that cause ozone depletion. The large ozone loss over Antarctica was the key observation that stimulated the definition and signing in 1987 of the Montreal Protocol, an international treaty establishing a schedule to reduce the production of the major chlorine- and bromine-containing halocarbons. Owing to its implementation, the near-surface total chlorine concentration showed a maximum in 1993, followed by a decrease of half a per cent to one per cent per year, in line with expectations. Remote-sensing data have revealed a peak in stratospheric chlorine after 1996, then a decrease of close to one per cent per year, in agreement with the surface observations of the chlorine source gases and model calculations. Here we present ground-based and satellite data that show a recent and significant increase, at the 2σ level, in hydrogen chloride (HCl), the main stratospheric chlorine reservoir, starting around 2007 in the lower stratosphere of the Northern Hemisphere, in contrast with the ongoing monotonic decrease of near-surface source gases. Using model simulations, we attribute this trend anomaly to a slowdown in the Northern Hemisphere atmospheric circulation, occurring over several consecutive years, transporting more aged air to the lower stratosphere, and characterized by a larger relative conversion of source gases to HCl. This short-term dynamical variability will also affect other stratospheric tracers and needs to be accounted for when studying the evolution of the stratospheric ozone layer.

Increased stratospheric hydrogen chloride in the el chichon cloud.

Spectroscopic observations of the total column amount of hydrogen chloride above an altitude of 12 kilometers in the latitude range 20 degrees to 40 degrees N have been made both before and 3 to 6 months after the eruptions of El Chichón Volcano in March and April 1982. In the region of the cloud of volcanic aerosols, the hydrogen chloride total column after the eruptions increased by approximately 40 percent, even after allowance is made for the global secular increase in hydrogen chloride of 5 percent per year. The column amounts of hydrogen fluoride show no such increase.

Spectroscopic detection of stratospheric hydrogen cyanide.

A number of features have been identified as absorption lines of hydrogen cyanide in infrared spectra of stratospheric absorption obtained from a high-altitude aircraft. Column amounts of stratospheric hydrogen cyanide have been derived from spectra recorded on eight flights. The average vertical column amount above 12 kilometers is 7.1 +/- 0.8 x 10(14) molecules per square centimeter, corresponding to an average mixing ratio of 170 parts per trillion by volume.

Temperature, cloud structure, and dynamics of venus middle atmosphere by infrared remote sensing from pioneer orbiter.

Further results from the Venus orbiter radiometric temperature experiment (VORTEX) on the Pioneer orbiter are presented. These are used to characterize the three-dimensional temperature field, the cloud structure, and the dynamics of the 60-to 130-kilometer altitude region of the Venus atmosphere. One of the new discoveries is a "dipole" structure at high latitudes, with two hot spots rotating around the pole, surrounded by banks of cold cloud.

Efficacy of a supplemental candy coproduct as an alternative carbohydrate source to lactose on growth performance of newly weaned pigs in a commercial farm condition.

The experiment investigated the effects of a supplemental candy coproduct (Chocolate Candy Feed [CCF]; International Ingredient Corp., St. Louis, MO), an alternative carbohydrate source to dietary lactose, on growth performance and on health status of nursery pigs. Crossbred pigs ( = 1,408; 21 d of age and 7.1 ± 0.3 kg BW; Smithfield Premium Genetics, Rose Hill, NC) were randomly assigned to 4 treatments (16 pens/treatment and 22 pigs/pen) in a randomized complete block design: 0, 15, 30, and 45% of lactose replaced by CCF based on equal amounts of total sugars. The experimental period was divided into 3 phases: phase I (1.8 kg diet/pig for 11 ± 1 d), phase II (6.8 kg diet/pig for 17 ± 2 d), and phase III (until 49 d after weaning). Pigs received a common phase III diet. The levels of lactose, supplied by whey permeate (79.3 ± 0.8% lactose), were 20, 8, and 0% in phase I, II, and III, respectively. All experimental diets contained the same levels of essential AA and energy (ME) for each phase. Fecal scores were observed on d 5, 7, and 9 after weaning. Blood samples were taken at the end of phase I and II to measure blood urea N. The duration of phase I tended to linearly decrease ( = 0.063) with increasing CCF. In phase I, the ADFI increased ( < 0.05) with increasing CCF whereas ADG and G:F did not change. In phase II, the duration and ADFI did not change whereas ADG linearly decreased ( < 0.05) with increasing CCF. However, the G:F was not changed as CCF increased. During phase I and II together, the duration was linearly decreased ( < 0.05) as CCF increased, whereas no difference in growth performance was observed. Overall, ADFI, ADG, and G:F were not affected by replacing whey permeate with CCF in diets, indicating no adverse effects of a candy coproduct as a carbohydrate substitute to lactose on growth performance of nursery pigs. Blood urea N did not change in phase I but tended to linearly increase ( = 0.088) in phase II as CCF increased. There were no differences in fecal scores and mortality as CCF increased. However, increasing CCF tended to linearly decrease ( = 0.083) morbidity, which implies no adverse effects of a candy coproduct replacement on health status of nursery pigs. In conclusion, a candy coproduct can be used to replace up to 45% of dietary lactose for nursery pigs without negative effects on growth performance or health status. A candy coproduct could be an economical alternative to partly replace the use of lactose in swine production.

Nutrient value of spray field forages fed to pigs and the use of feed enzymes to enhance nutrient digestibility.

This study determined the DE, ME, apparent total tract digestibility (ATTD) of N, and N retention of spray field forages (Bermuda grass, forage sorghum, and sweet sorghum) fed to pigs and the effects of the supplemental feed enzymes on energy and N utilization. A basal diet was formulated with 96% corn and 4% amino acids, minerals, and vitamins. Test diets contained 85% basal diet + 15% Bermuda grass, forage sorghum, or sweet sorghum. Allzyme SSF (Alltech, Nicholasville, KY) was used as a feed enzyme, which was composed of cellulase, glucanase, xylanase, phytase, and protease. The basal diet and test diets were evaluated by using 4 sets of 2 × 2 Latin square designs consisting of 2 pigs and 2 periods with a total of 32 barrows (38.7 ± 7.9 kg). Each period (10-d adjustment and 4-d collection) had 2 Latin squares. The 2 treatments were levels of enzyme supplementation (0 or 200 mg/kg). Pigs received experimental diets twice daily (0700 and 1700 h) at a fixed amount based on BW of pigs (0.09 × BW0.75 kg). On d 10, chromic oxide (0.5%) was added to the diets at 1700 h as an external marker. Fecal and urine samples were collected during 4 consecutive days. The basal diet contained 3,850 kcal DE/kg, 3,769 kcal ME/kg, 86.06% ATTD of N, and 71.10% N retention and was not affected by enzyme supplementation. Bermuda grass contained 893 kcal DE/kg, 845 kcal ME/kg, -16.50% ATTD of N, and -37.49% N retention and tended to be improved by enzyme supplementation to 1,211 kcal DE/kg (P = 0.098), 1,185 kcal ME/kg (P = 0.081), and -10.54% N retention (P = 0.076). The ATTD of N of Bermuda grass increased (P < 0.05) to 0.08% by enzyme supplementation. The forage sorghum contained 1,520 kcal DE/kg, 1,511 kcal ME/kg, -0.72% ATTD of N, and -16.99% N retention. The sweet sorghum contained 1,086 kcal DE/kg, 1,061 kcal ME/kg, -75.47% ATTD of N, and -49.22% N retention. Enzyme supplementation did not improve energy digestibility of forage sorghum and sweet sorghum. Nitrogen in these forages was poorly utilized. In conclusion, spray field forages including Bermuda grass, forage sorghum, and sweet sorghum can partly be utilized in pig feed to provide energy, although N is rather poorly digested. Feed enzymes could enhance both energy and N utilization in Bermuda grass but not sorghum.

Opioid control of growth hormone in the suckled sow is primarily mediated through growth hormone releasing factor.

Endogenous opioid peptides mediate the effect of suckling on LH and PRL in the domestic pig. However, the role of opioids in modulating GH during lactation in swine is not known. Primiparous sows that had been immunized against GRF(1-29) conjugated to human serum albumin (GRF-HSA, n = 5) or HSA (n = 4) were used to determine changes in GH after naloxone. Treatments were imposed in all sows on day 21 of lactation when antibody titers were 9100 +/- 1629. All sows received (i.v.) naloxone (0.25 mg/kg) or saline (0.0125 ml/kg) at 15 min intervals for 165 min. Active immunization against GRF-HSA during lactation decreased (P less than 0.05) mean concentration (4.8 +/- 0.2 vs 2.6 +/- 0.1 ng/ml) and frequency (1.5 +/- 0.3 vs 0.4 +/- 0.2 peaks/4 hr). Concentrations of LH and PRL were similar in GRF-HSA and HSA immunized sows. Naloxone suppressed (P less than 0.05) GH in all sows. In HSA sows, naloxone abolished episodic release of GH and decreased average, but not basal, concentrations of GH. In sows immunized against GRF-HSA, naloxone decreased (P less than 0.05) average and basal GH but failed to decrease frequency of GH release. Naloxone failed to alter frequency of LH release. Concentrations of PRL decreased (P less than 0.05) after naloxone in all sows. In conclusion, immunization against GRF-HSA blocked most of the effect of lactation on GH. Blocking opioid receptors with naloxone decreased GH and PRL in all sows. In contrast to previous findings naloxone had no effect on LH. Opioids alter concentrations of GH through a GRF dependent and GRF independent pathway.

A swine integrator's perspective on nutrient management procedures.

The goal of pork producers is to operate in a sustainable manner that includes among other requirements, environmental soundness, social acceptability, and profitability. Gains in efficiency have reduced nutrient by-products per pig, but competitive forces have led to specialization, larger farms, and concentrated areas of production that have resulted in new opportunities related to nutrient management. Available technology uses on-farm processing or storage facilities, and manure is applied to the land as an organic fertilizer. Knowledge of nutrient content of soils and crop uptake of nutrients is incorporated into manure application and crop removal plans to prevent either runoff or nutrient buildup on the land. This is to ensure water quality protection. Existing systems are adequate but lack flexibility, require effective management, may not have been incorporated into older farms, and do not offer obvious solutions to odor concerns. Cost-effective alternatives should address those needs. Advancement in nutrient management procedures will likely accelerate the ongoing changes in the structure of the swine industry.

Enhancement of sow reproductive performance by beta-carotene or vitamin A.

Two experiments were conducted at separate commercial farms. In Exp. 1, all primiparous sows and an equal number of multiparous sows weaned each week were randomly assigned to one of four treatment groups. Treatments consisted of one i.m. injection on the day of weaning of 0, 50, 100, or 200 mg of beta-carotene. Sows were checked for estrus with boars once daily and mated at first estrus after weaning. A sample of sows (n = 100) was selected for determination of plasma beta-carotene and vitamin A. Blood samples were obtained from another group (n = 120) 14 d after injection to determine plasma progesterone. In Exp. 2, treatments consisted of i.m. injection of 200 mg of beta-carotene, 50,000 IU of vitamin A, or vehicle on the day of weaning, on the day of mating, and on d 7 after mating. In both experiments, the sow diet was supplemented with 11,000 IU/kg of vitamin A. In Exp. 1, there was no effect of dose of beta-carotene on the interval from weaning to estrus or on the repeat service rate. There was a dose x parity interaction on the number of pigs born dead (P < .01) and born alive (P < .10), because treatment with beta-carotene did not affect reproduction in primiparous sows, but litters subsequently farrowed by multiparous sows had more pigs born alive and fewer pigs born dead. There was a dose x day interaction (P < .05) on plasma beta-carotene; beta-carotene was elevated on d 6 and 13 after injection.(ABSTRACT TRUNCATED AT 250 WORDS)

Correlated responses in body composition based on selection for different indicator traits in mice.

Correlated responses in whole-body composition were determined in 12-wk-old male mice from replicate lines selected for 12 generations for high (HF) or low (LF) epididymal fat pad weight as a percentage of body weight (EPID) and high (HL) or low (LL) hind carcass weight as a percentage of body weight. The HF and LF lines diverged (P less than .01) in body fat percentage (FAT) and subcutaneous depot fat by 93 and 71%, respectively, of the control line (RC) mean. EPID increased (P less than .01) proportionately more than FAT in the HF line; EPID decreased (P less than .01) proportionately less than FAT in LF. Protein, fat and water as a percentage of empty body weight showed negative correlated responses (P less than .01) due to selection for EPID, but lean body mass, body weight and body length had positive correlated responses (P less than .01). Correlated responses of fat-free protein and ash percentage were minor. Correlated responses in HL and LL were the mirror images of those in HF and LF, but they generally were of smaller magnitude. The results indicate that, although there are high positive genetic correlations between fat depots in mice, local control of lipogenesis and(or) lipolysis exists at different sites of fat deposition. Further, the lack of correlated responses in fat-free percentage of protein (and percentage of ash) suggests that additive genetic variances are low for these traits and(or) the genetic correlations of these traits with the selection criteria are low.

The effect of dietary protein on performance and immune response in weanling pigs subjected to an inflammatory challenge.

A total of 96, 21-d-old, crossbred weanling pigs (average initial weight was 6.0 kg) were assigned to one of six treatments to investigate the effect of dietary protein on performance and immune function of Escherichia coli lipopolysaccharide (LPS)-challenged and unchallenged pigs. A control diet was formulated to contain 14.7 MJ of DE/kg, 14 g of CP/MJ of DE, and 7 g of lysine/100 g of CP. Diets low and high in protein were formulated by changing protein levels to 60 or 120% of the control diet. On d 7 and 21, pigs were challenged with either a LPS solution or a saline solution. Lymphocyte blastogenesis was measured 2 d after LPS challenges and antibody response to sheep red blood cells (SRBC) or ovalbumin was measured 3 d after the challenges. Gain and feed consumption were determined 3 d after each LPS injection and at weekly intervals for a total period of 5 wk. Injection of LPS decreased daily gain, feed intake, feed efficiency, and efficiency of protein utilization (P < .05). No interactive effects between LPS challenge and dietary protein were observed for pig performance (P > .10). Daily gain and feed efficiency were improved when protein level was increased from 60 to 100% of the control diet (P < .01). Efficiency of protein utilization for weight gain was lower when the 120% protein diet was fed (P < .01). Antibody response to SRBC or ovalbumin was not affected by treatments.(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of dietary protein, fat or amino acids on the response of weanling swine to aflatoxin B1.

Two experiments were conducted using corn from clean or aflatoxin B1 (AFB1)-contaminated (182 ppb) sources. Weanling pigs (28 d) were fed one of eight dietary treatments arranged in a 2 x 2 x 2 factorial design. In Exp. 1 (192 pigs), treatments varied in corn source (clean or AFB1-contaminated), CP level (18 or 20%) and added fat (0 or 5%). At the end of the 28-d growth trials, plasma samples were obtained. An AFB1 x CP level interaction was detected (P less than .05) for growth rate (ADG), feed intake (FI) and feed/gain ratio (F/G). Feeding AFB1 reduced (P less than .05) ADG (.30 vs .37 kg/d) and FI (.57 vs .66 kg/d) and increased F/G (1.88 vs 1.78) of pigs fed 18% CP diets. Performance of pigs fed 20% CP diets was not altered by AFB1. Adding 5% fat to diets improved (P less than .05) F/G but did not improve ADG of pigs fed AFB1. There was an AFB1 x CP x fat interaction (P less than .05) for plasma cholesterol. Adding fat or increasing the CP level prevented the depression of plasma cholesterol in pigs fed AFB1. In Exp. 2 (96 pigs), all diets contained 18% CP and the treatments varied in corn source (clean or AFB1-contaminated), added L-lysine HCl (0 or .25%) and added DL-methionine (0 or .15%). Feeding AFB1 reduced (P less than .05) ADG of pigs fed the 18% CP diet (.44 vs .50 kg/d) but not of pigs fed diets supplemented with .25% lysine.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of feeding sows fat or fructose during late gestation and lactation.

The effects of dietary fat or fructose supplementation during late gestation and lactation on sow milk production and composition and on progeny were examined. On d 88 of gestation, 24 sows were allotted by parity to three dietary treatments (eight sows/treatment). Treatments were 1) a 12.5% crude protein, corn-soybean meal control, 2) the control + 10% added fat or 3) the control + 23% high fructose corn syrup. All treatments were fed to supply 1.82 kg/d of the control diet from d 89 of gestation to parturition with sows in treatments 2 or 3 receiving .18 kg of additional fat or .53 kg of additional high fructose corn syrup, respectively. Feed was gradually increased from d 1 to 7 of lactation to 4.54 kg/d of the control diet (plus .45 kg of added fat and 1.33 kg of added fructose for treatments 2 and 3) and remained at these levels for the remainder of the 21 d lactation period. All treatments were iso-nitrogenous; treatments 2 and 3 were iso-caloric. Litter birth weights, number of pigs born alive, weaning weights and piglet survival rate were not affected by sow treatment. Stillbirths were less (P less than .05) for sows fed fat. Lipid content of milk 24 h post-farrowing was greater (P less than .05) from sows fed fat compared with sows fed fructose. Milk production estimates indicated that multiparous sows fed fat produced more (P less .05) milk than sows fed the control diet. On d 112 of gestation and d 15 of lactation, serial blood samples were drawn to monitor sow response to a glucose challenge (1 g/kg body weight).(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of immune challenge, dietary energy density, and source of energy on performance and immunity in weanling pigs.

The objective of this study was to investigate the effects of nutrient density and dietary energy source on performance and immune function of weanling pigs that were either challenged or not challenged with Escherichia coli lipopolysaccharide (LPS). A basal diet was formulated to contain 14 g CP/MJ DE and 7 g lysine/100 g CP. Sulfur amino acids, threonine and tryptophan were kept constant relative to lysine. Experimental diets were mixed using 70 parts basal diet and either 30 parts starch or an isocaloric amount (14 parts) of lard. Diets were fed either for ad libitum intake or on a pair-feeding basis to evaluate effects of diet nutrient density or source of energy, respectively. On d 9 and 25, pigs were challenged i.m. with either 1 mL of a LPS solution or a control solution. Lymphocyte blastogenesis was measured 2 d after the LPS administration and antibody response to sheep red blood cells (SRBC) or ovalbumin was determined 3 d after challenge. No interactive effects on performance were observed between LPS challenge and energy density or source of energy (P > .10). Injection of LPS tended to reduce feed intake and daily gain (P < .10), but not efficiency of feed or energy utilization. Addition of fat to the diets improved feed efficiency and efficiency of energy utilization for gain (P < .05). No consistent effects of LPS challenge, energy density, or source of energy were observed for lymphocyte blastogenesis. Antibody response to ovalbumin, but not to SRBC, was decreased by fat (P < .05). Results indicate that increasing energy density of the diet did not alter the performance depression due to LPS challenge. Addition of fat to the diet improved feed efficiency and efficiency of energy conversion but may depress the humoral immune response. Effects of fat on the immune response may depend on the immune status of the pig.

A comparison of an 8- versus 16-hour photoperiod during lactation on suckling frequency of the baby pig and maternal performance of the sow.

Seventeen crossbred sows were used in a lactation trial to compare the effects of a 16-h photoperiod with an 8-h photoperiod from d 107 of gestation to weaning at 28 d postpartum. Crossbred sows were used to compare the effects of 16-h (n = 8) and 8-h (n = 9) photoperiods on litter and maternal performance traits. Females were moved into two identical farrowing rooms under either 16- or 8-h photoperiods on d 107 of pregnancy, litters were equalized across treatments at birth and the treatments terminated at weaning on d 28 postpartum. Traits evaluated included litter size at birth and weaning, 21-d pig and litter weights, milk yields and composition on d 15, litter survival rates, suckling frequency for a 24-h period on d 13 and percentage of sows returning to estrus and days to estrus after weaning. Pigs exposed to 16 h light nursed more often (P less than .05) than pigs exposed to 8 h light over a 24-h period. This advantage was greatest during the 4-h periods of 1200 to 2000, 0000 to 0400 and 0800 to 1200 h. This difference is perhaps an explanation of why litters exposed to 16 h light weaned more (P less than .05) pigs/litter with heavier (P less than .01) 21-d litter weights. Nonsignificant advantages were also seen in milk yield and litter survival percentage. In addition, sows exposed to 16 h light had higher (P less than .05) total solids content of their milk.

Concentrations of hormones and metabolites, estimates of metabolism, performance, and reproductive performance of sows actively immunized against growth hormone-releasing factor.

Cyclic females actively immunized against growth hormone-releasing factor (GRF; n = 5) or human serum albumin (HSAi; n = 4) were used to determine the effects of reduced serum somatotropin (ST) and IGF-I on metabolism and production in gestating and lactating sows. Sows farrowed, pigs were weaned at 28 d of lactation, and sows were observed for estrus after weaning. Blood samples were collected at 15-min intervals for 5 to 6 h on d 110 of gestation and d 21 of lactation. Mean ST (nanograms/milliliter) was less (P < .05) in GRFi than in HSAi sows at d 21 of lactation, but it was similar at d 110 of gestation. Serum concentrations of IGF-I were less (P < .05) in GRFi than in HSAi sows at d 21 of lactation but not at d 110 of gestation. Serum thyroxine was greater (P < .05) in GRFi than in HSAi sows during gestation and lactation. Sows actively immunized against GRF weighed less (P < .01) and had more backfat (P < .01) at d 110 of gestation than HSAi sows; in vitro glucose oxidation and lipogenic rate of adipose tissue were greater (P < .05 for treatment x day interaction) in GRFi than in HSAi sows at d 110 of gestation. Across treatment, mammary gland oxidation of glucose and glucose clearance rates increased (P < .05), whereas adipose tissue utilization of glucose decreased (P < .05) during lactation. During lactation, GRFi sows mobilized more (P < .05) backfat than did controls.(ABSTRACT TRUNCATED AT 250 WORDS)

Nutritional, physiological, genetic, sex, and age effects on fat-free dry matter composition of the body in avian, fish, and mammalian species: a review.

The purpose of this review is to outline and interpret the effects of nutrition, physiological state, sex, genetics, and age on composition of the fat-free dry matter of birds, mammals, and fishes in order to test the hypothesis that the protein:ash ratio in the body is constant. Calculations from a broad array of published data revealed that nutritional factors, including mineral, protein and amino acid nutriture, frequency and level of feeding, and energy intake and nonnutritional factors, including physiological state, sex, genetic background, and age of animal, may each alter the ratio of protein:ash in the body. All or part of the response may be associated with changes in accretion of body protein and(or) skeletal development and mineralization imposed by these nutritional and nonnutritional factors. In most cases of amino acid or protein deficiency, the protein:ash ratio was decreased relative to the control because the deposition of protein in muscle and viscera was reduced more than the growth and mineralization of the skeleton. In other cases, the protein:ash ratio was increased relative to a control because the dietary Ca or P intake or absorption limited skeletal mineralization. More knowledge is needed of how skeletal development and protein:ash ratio in the body is regulated, especially under the influence of nutritional, ontogenetic, and physiological variables among different genotypes of mammals, birds, and fishes. Documentation that the protein:ash ratio in the whole body of representative mammals, birds, and fishes is not constant, but is subject to manipulation, has important physiological and economic implications for developing food animals for the efficient production of lean meat.

Methionine, choline and sulfate interrelationships in the diet of weanling swine.

Experiments were conducted to examine the interrelationships between methionine, choline and inorganic sulfate in the diet of weanling pigs, and to evaluate the selenium (Se) status of pigs fed diets with or without supplemental sulfate. Two trials utilized 288 weanling (3-wk-old) pigs allotted to dietary treatment based on weight, sex and litter origin. There were six pigs/pen and three replicate pens/treatment in each trial. The basal corn-soybean meal diet was formulated to supply .55% sulfur amino acids and contained a choline and sulfur-free vitamin and mineral premix. Lysine was added to provide a total of 1.13% lysine. Seven additional treatments were formulated by substituting for corn .17% DL-methionine, .29% choline dihydrogen citrate or .25% Na2SO4 to create a 2(3) factorial arrangement of treatments. There were methionine X choline X sulfate interactions for average daily gain (P less than .001) and feed-to-gain ratio (F:G; P less than .05). Adding choline, methionine, Na2SO4 or choline plus methionine to the basal diet did not improve gains. However, when Na2SO4 plus methionine or Na2SO4 plus choline were added, daily gains were increased (P less than .05) and F:G was improved (P less than .1). Addition of all three supplements did not result in a further increase in gain. Pigs fed choline-supplemented diets had higher (P less than .01) hematocrit and tended (P = .07) to have increased hemoglobin concentration. There was no effect on serum triglycerides or alkaline phosphatase activity due to dietary treatment. The concentration of Se in muscle, liver, kidney and blood was not influenced by sulfate content of the diet.

Volatile compound content and fatty acid composition of pork as influenced by linoleic acid content of the diet.

Eighty pigs (average weight of 60 kg) were allotted by weight and sex to pens and treatments. There were four dietary treatments, five pens per treatment, and four pigs per pen. Diets consisted of a typical corn-soybean mix containing 9% total fat, 3% from the corn-soybean mix and 6% added. The four dietary treatments included 1) 6% safflower oil, 2) 4% safflower oil and 2% tallow, 3) 2% safflower oil and 4% tallow, and 4) 6% tallow, resulting in 6.1, 4.6, 3.2, and 1.76% linoleic acid, respectively, in the diet. Pigs were slaughtered at an average weight of 100 kg. Proximate composition, tristimulus color coordinates (L, a, and b values), pH, and flavor difference of the longissimus muscle (LM) were evaluated. Fatty acid content (milligrams per 100 grams of tissue) of the subcutaneous fat and LM and headspace volatile content of the LM were determined by capillary gas liquid chromatography. Proximate composition, color, pH, and flavor of the LM were not influenced by diet. Fatty acid content of the subcutaneous fat and LM and volatile content of the LM were influenced by diet. Increased levels of safflower oil in the diet resulted in less C16:0 and C18:1 and more C18:2, C20:2, and C20:3 in the subcutaneous fat. The LM contained more C18:2 and less C18:3 and C24:0 due to increased levels of safflower oil in the diet. Compared with the 6% tallow diet, LM from pigs fed the 4 or 6% safflower diets contained more pentanal, hexanal, 2-heptanone, trans-2-heptenal, 2-pentyl furan, 2-ethyl-1-hexanol, decanal, and undecanal.(ABSTRACT TRUNCATED AT 250 WORDS)

Effect of level, source and duration of feeding of supplemental energy in sow diets of metabolic and hormonal traits related to energy utilization in the baby pig.

In each of two trials, 30 sows were assigned to six energy-supplemented diets for 5 (trial 1) or 35 d (trial 2) before farrowing, and the effects on sow milk and pig survival characteristics were examined. Treatments consisted of 1.6 kg/d of a basal diet plus .09, .18 or .27 kg of animal fat/d or .20, .39 or .58 kg of cornstarch/d. Two pigs were killed at birth after blood samples were taken and before suckling. Two pigs per litter were fasted to 24 h and two to 48 h of age. Blood glucose was increased (P less than .05) at birth in pigs from sows fed fat in the 35-d feeding, whereas blood glucose was not different in pigs in the short-term feeding of diets Beta-hydroxybutyrate was highest in blood from pigs in the fat-fed groups after a 48-h fast, which was an indication of increased fat metabolism. Beta-hydroxybutyrate was also higher (P less than .05) after a 24 h fast in livers of pigs from sows fed the highest level of fat in both trials than in livers of pigs from sows fed the same level of cornstarch. There were also treatment differences (P less than .05) in liver glycogen content, oxidation of palmitate to CO2, oxidation of glucose to CO2, number of pigs born dead, birth weight and colostrum total lipids and energy content. No treatment-related differences in levels of FFA, triiodothyronine, thyroxine or glucagon in blood of the offspring were observed.