@article{christensen_wineland_fasenko_donaldson_2002, title={Egg storage alters weight of supply and demand organs of broiler chicken embryos}, volume={81}, ISSN={["1525-3171"]}, DOI={10.1093/ps/81.11.1738}, abstractNote={Storage of fertilized eggs for more than 10 d prior to incubation decreases embryonic viability. The hypothesis was tested that embryos may grow differently following egg storage. Eggs from which embryos survived following storage (ST) were compared to eggs from a second line that did not (NOST). Three identical, independent trials were conducted using fertile eggs from both lines at two ages (peak lay and > 53 wk). Eggs were stored for 1 or 14 d prior to setting in the incubator. At 3-d intervals during development, embryos were carefully removed from the eggs, the yolks were excised and carcasses were weighed. Beginning at 12 d of incubation whole body, heart, liver and thigh tissues were weighed to assess allometric growth of supply (heart and liver) and demand (thigh muscle) tissues. Storage of eggs from both lines and from hens of both ages decreased BW differently throughout incubation. Line, Age and Storage interacted to affect embryonic BW and organ weights. Embryo weights were consistently heavier in NOST line eggs from older breeder flocks stored for 14 d than those from ST line eggs. It was concluded that extended storage of fertile eggs prior to setting affects embryonic growth to enhance survival.}, number={11}, journal={POULTRY SCIENCE}, author={Christensen, VL and Wineland, MJ and Fasenko, GM and Donaldson, WE}, year={2002}, month={Nov}, pages={1738–1743} }
 @article{christensen_wineland_fasenko_donaldson_2002, title={Egg storage effects on plasma glucose and supply and demand tissue glycogen concentrations of broiler embryos (vol 80, pg 1729, 2001)}, volume={81}, DOI={10.1093/ps/81.4.595}, number={4}, journal={Poultry Science}, author={Christensen, V. L. and Wineland, M. J. and Fasenko, G. M. and Donaldson, W. E.}, year={2002}, pages={595} }
 @article{christensen_wineland_fasenko_donaldson_2001, title={Egg storage effects on plasma glucose and supply and demand tissue glycogen concentrations of broiler embryos}, volume={80}, ISSN={["1525-3171"]}, DOI={10.1093/ps/80.12.1729}, abstractNote={The hypothesis was tested that enhanced embryonic carbohydrate metabolism may enable embryos to survive egg storage effects. As lines of broiler breeders age, some lines resist detrimental effects of egg storage on embryonic survival, whereas others do not. Fertile eggs were obtained from two lines differing in storage ability. Eggs from each line by age group were stored for 1 or 14 d prior to setting. Eggs were distributed randomly into a single machine and incubated under standard conditions. Beginning at 17 d of incubation, immediately prior to the plateau stage in oxygen consumption, embryos from each of the treatment groups were sampled for BW, organ growth, glycogen concentration, and plasma glucose concentrations. Sampling continued through hatching. Plasma glucose concentrations increased significantly, and hepatic glycogen concentrations declined as embryos approached hatching. The rate at which glycogen was accrued into muscle and heart tissue displayed a significant three-way interaction among line, age, and storage. Embryos from the line that resisted storage mortality maintained greater glycogen concentrations in muscle and heart tissues than those from the line and age with diminished survival rates. It was concluded that embryonic survival rates differ following egg storage because of the ability of the embryo to accrue and maintain adequate carbohydrate for growth and function of vital demand tissues.}, number={12}, journal={POULTRY SCIENCE}, author={Christensen, VL and Wineland, MJ and Fasenko, GM and Donaldson, WE}, year={2001}, month={Dec}, pages={1729–1735} }
 @article{christensen_mcmurtry_donaldson_nestor_2001, title={Incubation temperature affects plasma insulin-like growth factors in embryos from selected lines of turkeys}, volume={80}, ISSN={["0032-5791"]}, DOI={10.1093/ps/80.7.949}, abstractNote={An experiment was conducted to test the hypothesis that incubator temperature may affect circulating insulin-like growth factors (IGF-I and IGF-II). In prior studies, growth of turkey embryos was altered by increasing incubator temperatures. Interestingly, the embryonic growth of a growth-selected line (F) was reduced, whereas embryos from an egg-production-selected line (E) did not alter embryonic growth but altered organogenesis. Growth of the F and E lines was altered experimentally in the current study by increasing incubator temperature from 36.8 to 37.2 C during the last 3 d of incubation. Embryonic blood samples were taken and analyzed for glucose, glucagon, IGF-I, and IGF-II concentrations. Increased incubator temperature elevated embryonic plasma glucose concentrations of all treatments compared to controls, which was accompanied by increased plasma glucagon concentration only in the E line embryos. Line and treatment interacted to affect IGF-I and IGF-II concentrations of embryo and hatchlings. Line E embryos increased IGF-I in response to the higher temperature, but controls did not; F embryos altered IGF-II in response to treatment, but controls did not. Alterations in IGF-I in E corresponded to growth responses, whereas IGF-II in F corresponded to metabolic responses. We concluded that changes in turkey embryo growth rates to incubator temperature involved changes in IGF-I. Additionally, IGF-II and glucagon are involved in intermediary metabolism during higher temperature exposure.}, number={7}, journal={POULTRY SCIENCE}, author={Christensen, VL and McMurtry, JP and Donaldson, WE and Nestor, KE}, year={2001}, month={Jul}, pages={949–954} }
 @article{christensen_grimes_donaldson_lerner_2000, title={Correlation of body weight with hatchling blood glucose concentration and its relationship to embryonic survival}, volume={79}, ISSN={["1525-3171"]}, DOI={10.1093/ps/79.12.1817}, abstractNote={The negative correlation between selection for rapid growth and embryonic survival was investigated. Embryonic growth was assessed with hatchling weights of a closed population of commercial turkey breeders. Hatchling weights were highly significantly (P < 0.0001) and positively correlated with blood glucose concentrations at hatching. This relationship existed for both tom and hen poults. Significant differences among dams for hatchling blood glucose were observed. Further experiments examined dams selected for producing poults hatching with high (High) or low (Low) blood glucose concentrations. The High embryos were in larger-sized eggs with the same eggshell conductance but with significantly lower conductance constants than the Low embryos, suggesting that Low had longer incubation periods. High embryos grew faster than Low embryos with elevated organ glycogen concentrations. Organic acid analysis indicated elevated plasma alpha-ketoglutarate, urate, and beta-hydroxy butyrate concentrations, suggesting a greater reliance on gluconeogenesis for the High group. Posthatch growth was significantly positively correlated with hatchling blood glucose concentrations in toms but not in hens. Tom poults hatching with elevated glucose were heavier than low glucose hatch mates until 22 wk of age, but hen poults displayed no differences until 16 wk when High hens weighed less than Low hens. These data suggest that the negative correlation between rapid growth and embryonic survival is related to egg-shell conductance constants and embryonic energy metabolism.}, number={12}, journal={POULTRY SCIENCE}, author={Christensen, VL and Grimes, JL and Donaldson, WE and Lerner, S}, year={2000}, month={Dec}, pages={1817–1822} }
 @article{christensen_grimes_donaldson_lerner_2000, title={Paternal influences on turkey embryonic growth in the absence of changes in egg weight and eggshell conductance}, volume={79}, ISSN={["1525-3171"]}, DOI={10.1093/ps/79.12.1810}, abstractNote={The hypothesis was proposed that embryonic growth could be influenced paternally in the absence of changes in egg weight or eggshell conductance. Sire families were established by selecting 11 sires based on blood sampling of approximately 50 commercial turkey males. Southern blot analysis was used to identify the most distantly related individuals in the subpopulation. Five hen siblings or half-siblings of the males were randomly assigned to each male to randomize effects of egg size and eggshell conductance. Artificial inseminations were performed weekly for 17 wk, using each sire with the assigned hens. Fertilized eggs were collected and set in incubators at biweekly intervals. Offspring were observed at the time of hatching for sex, body weight, and blood glucose concentration. Significant differences among sires were observed at hatching for poult weights and blood glucose concentration, and a significant correlation between the BW and glucose concentration was noted. Progeny of sires with the highest and lowest BW and blood glucose concentrations were subsequently compared. Mean BW of poults from different sires differed by as much as 10 g, although they were hatched from eggs of the same weight. Elevated blood glucose was associated with heavier BW; heavier heart, liver, and muscle weights; a rapid utilization of glycogen at pipping; and increased gluconeogenesis as measured by plasma organic acids and glucose-6-phosphatase activity. We conclude that poult embryonic growth differs even when not mediated by egg size and functional characteristics.}, number={12}, journal={POULTRY SCIENCE}, author={Christensen, VL and Grimes, JL and Donaldson, WE and Lerner, S}, year={2000}, month={Dec}, pages={1810–1816} }
 @article{christensen_donaldson_nestor_mcmurtry_1999, title={Effect of genetics and maternal dietary iodide supplementation on glycogen content of organs within embryonic turkeys}, volume={78}, ISSN={["1525-3171"]}, DOI={10.1093/ps/78.6.890}, abstractNote={In prior studies it was shown that the growth of turkey embryos was dependent upon maternal dietary iodide as well as genetic selection. The current study posed the question of which organ systems respond to these variables. Embryos from lines selected for 16-wk BW grew at the same rate as unselected embryos from the randombred population serving as the initial source of the selected line until approximately 21 d of incubation (selected = F; randombred control = RBC2). Line differences in growth of F embryos could be accounted for increased liver and heart growth at the expense of muscle growth. Muscle growth increased in the growth-selected line prior to pipping. Muscle growth was affected less when dams were selected for egg production (selected = E; randombred control = RBC1). Muscle growth was slowed in E line embryos compared to that of RBC1, and liver and heart growth were slowed at internal and external pipping stages in E embryos compared to RBC1. Early muscle growth was augmented when F dams were fed supplemental iodide. A similar response was observed in E line embryos but occurred at a later stage of development. Measurements indicated decreased tissue glycogen in liver, heart, and muscle of selected lines may be one possible mechanism by which growth or organ function may come in conflict.}, number={6}, journal={POULTRY SCIENCE}, author={Christensen, VL and Donaldson, WE and Nestor, KE and McMurtry, JP}, year={1999}, month={Jun}, pages={890–898} }
 @article{christensen_donaldson_nestor_mcmurtry_1999, title={Effect of genetics and maternal dietary iodide supplementation on turkey embryonic growth}, volume={78}, ISSN={["1525-3171"]}, DOI={10.1093/ps/78.6.883}, abstractNote={Embryonic growth of a turkey lines selected for 16-wk BW (F) or 180-d egg production (E) was measured and compared to randombred controls (RBC2 or RBC1). Egg weight at setting relative to poult weight at hatching indicated increased growth in F as well as E embryos compared to randombred controls. Eggs from F weighed 10 g more than those of RBC2 (P < or = 0.0001) but the poults at hatching were only 8 g heavier (P < or = 0.0001). Water vapor loss during incubation indicated that only 0.9% of the difference could be accounted for by water vapor loss. Selection for increased 16-wk BW resulted in decreased embryo growth rates relative to hatchling mass (P < or = 0.0001) beginning at Day 16 of incubation compared to that of RBC2. Eggs from E weighed 15 g less than RBC1 (P < or = 0.0001) but produced poults weighing only 7 g less (P < or = 0.0001). Incubation water vapor loss was depressed in E compared to RBC1 (P < or = 0.0001) but accounted for only 1.4% of the difference between hatchling weights. Selection for egg production increased embryo growth rates (relative to hatchling mass) measured at 4-d intervals compared to those of the RBC1 line (P < or = 0.05). Iodide supplementation of the maternal diet depressed (P < or = 0.05) glycogen in F embryos but interacted with line to generally increase glycogen in E embryos. Increased glycogen was related to increased growth rates in E but not F line embryos. It may be concluded that iodide supplementation of the material diet and genetics are determinants of embryonic growth in turkeys.}, number={6}, journal={POULTRY SCIENCE}, author={Christensen, VL and Donaldson, WE and Nestor, KE and McMurtry, JP}, year={1999}, month={Jun}, pages={883–889} }
 @article{christensen_donaldson_nestor_1999, title={Effect of supplemental oxygen on blood plasma organic acids within embryos from selected lines of turkeys}, volume={78}, ISSN={["0032-5791"]}, DOI={10.1093/ps/78.11.1601}, abstractNote={The hypothesis was tested that increased oxygen tensions during the plateau stage of oxygen consumption (25 and 26 d of incubation) would cause different metabolic responses from embryos selected for increased egg production or growth. Embryos were exposed to 171 or 152 mm Hg partial pressure of oxygen from 25 to 28 d of incubation, a time when the oxygen conductance properties of the eggshell are exceeded by the embryonic tissue demands for oxygen. Carbohydrate and lipid metabolism were observed by measuring plasma organic acids in embryos from selected lines and randombred controls. (E was selected for increased egg production; RBC1 is the randombred line from which it was selected. F was selected for increased BW; RBC2 is the randombred line from which it was selected.) During the plateau stage in oxygen consumption, RBC2 embryos responded to added oxygen by utilizing fat rather than carbohydrate, whereas F embryos responded by using less fat as well as less carbohydrate from the liver and kidney. The response of F embryos to added oxygen is the opposite that might be expected for aerobic metabolism. The reason that selection for growth has resulted in such a metabolism is unknown. The E embryos displayed depressed lactate and beta-hydroxybutyrate levels, but plasma urates were elevated compared with RBC1, suggesting that the selection for egg production has also resulted in a unique metabolism. The embryonic processes described in the current study suggest that selected embryos are unable to respond to elevated partial pressure of oxygen by adjusting energy metabolism, which may result in increased embryonic mortality during this stage.}, number={11}, journal={POULTRY SCIENCE}, author={Christensen, VL and Donaldson, WE and Nestor, KE}, year={1999}, month={Nov}, pages={1601–1605} }
 @article{christensen_donaldson_nestor_1999, title={Length of the plateau and pipping stages of incubation affects the physiology and survival of turkeys}, volume={40}, ISSN={["1466-1799"]}, DOI={10.1080/00071669987737}, abstractNote={1. The hypothesis tested was that accelerating the rate at which a turkey embryo passes through the Plateau and Pipping stages (incubation days 25 to 28) affects growth and embryonic mortality. 2. Eggs from 4 genetic lines were incubated similarly until 24 d of incubation. The eggs were divided at random, half incubated at 36.8 degrees C (CON) and the remaining half incubated at 37.3 degrees C (FAST). 3. The passage time for each developmental stage was recorded at 4 h intervals. Tissues were collected and measured for growth, and glycogen concentration at each developmental stage in response to the accelerated development. 4. The FAST treatment accelerated passage through the Plateau in some lines but not others, but time to pip was shortened in all genetic lines. Embryonic survival rate was affected differently by FAST. Slower growth in response to FAST enhanced survival. 5. In conclusion the rate at which genetically different embryos grow, mature and survive may involve choices among the 3 processes.}, number={2}, journal={BRITISH POULTRY SCIENCE}, author={Christensen, VL and Donaldson, WE and Nestor, KE}, year={1999}, month={May}, pages={297–303} }
 @article{christensen_mcmurtry_donaldson_nestor_1999, title={Supplemental oxygen affects plasma insulin-like growth factors in embryos from selected lines of turkeys}, volume={78}, ISSN={["1525-3171"]}, DOI={10.1093/ps/78.11.1606}, abstractNote={Recent advances in our understanding of insulin-like growth factors (IGF) have improved our knowledge of the physiological roles of these peptide hormones during avian embryogenesis. However, little is known about changes in plasma IGF in response to changes in environmental factors. The objective of the studies reported herein was to examine the response of IGF-I and IGF-II in turkey embryos to changes in incubator gaseous conditions. Two experiments were conducted in which the fractional percentage of oxygen in the incubation atmosphere, a factor known to influence the energy metabolism of embryos, was investigated for its effects on circulating IGF-I and IGF-II in developing turkey embryos. Oxygenation during pipping and hatching is known to depress lactate, urates, and beta-hydroxybutyrate in growth-selected poult embryos, but elevate them in randombred control poult embryos. Plasma concentrations of IGF-II were similarly depressed in the growth-selected hatchlings. Circulating growth factor concentrations were influenced by oxygenation in lines of turkeys in which greater oxygen concentrations enhanced cardiac growth. Enhanced cardiac growth was inversely related to IGF-I concentrations in those genetic lines of turkeys. It was concluded that changes in poult embryo energy balance as well as changes in growth to adapt to environmental incubator conditions may involve changes in IGF-I and IGF-II. These changes appeared dependent on the genetics of embryos; embryos selected for growth show more fluctuation in response to environmental oxygen than embryos selected for egg production.}, number={11}, journal={POULTRY SCIENCE}, author={Christensen, VL and McMurtry, JP and Donaldson, WE and Nestor, KE}, year={1999}, month={Nov}, pages={1606–1610} }
 @article{knowles_donaldson_andrews_1998, title={Changes in fatty acid composition of lipids from birds, rodents, and preschool children exposed to lead}, volume={61}, ISSN={["0163-4984"]}, DOI={10.1007/BF02784024}, abstractNote={Chronic treatment with inorganic lead (Pb) has been shown to increase the proportion of arachidonic acid (ArA), as well as the arachidonate/linoleate (ArA/LA) ratio, in the fatty acids of lipids from a variety of avian tissues. Changes in two fatty acid-mediated phenomena, peroxidation of membrane lipids and synthesis of eicosanoid cytokines, are associated with this enhanced ArA content. The authors are not aware of any reports in the literature in which these effects of Pb have been described for any animals other than birds. In the current study, the authors investigated the effect of Pb on lipid metabolism in three species: avian, rodent, and human. The group of children identified as suffering environmental Pb exposure were from a Pb-surveillance program and had blood Pb concentrations (PbB) averaging 23 microg/dL. Turkey poults fed 100 ppm dietary Pb as Pb acetate-trihydrate for 19 d had a PbB of 46 microg/dL. Gastric intubation of rats with 80 mg Pb/kg/d for 10 d resulted in a PbB of 74 microg/dL. We analyzed fatty acid composition of whole blood from children, poults, and virgin rats. Low-dose (nongrowth inhibitory) Pb exposure resulted in significantly increased ArA concentration and ArA/LA ratio in blood from all species. Also analyzed were plasma and liver of poults, virgin rats, and pregnant rats and their fetuses. In plasma and liver from Pb-treated poults and virgin rats, ArA and the ArA/LA ratio were again enhanced. Pb intoxication also affected omega3 composition, increasing the concentrations of all long-chain omega3 fatty acids of fetuses from Pb-treated pregnant dams. The authors propose that altered fatty acid metabolism may be responsible for some indications of Pb poisoning. Possible consequences mediated through lipid peroxidation and production of ArA-derivative eicosanoids are considered.}, number={2}, journal={BIOLOGICAL TRACE ELEMENT RESEARCH}, author={Knowles, SO and Donaldson, WE and Andrews, JE}, year={1998}, month={Feb}, pages={113–125} }
 @article{christensen_donaldson_nestor_1997, title={Effects of an oxygen-enriched environment on the survival of turkey embryos between twenty-five and twenty-eight days of age}, volume={76}, ISSN={["0032-5791"]}, DOI={10.1093/ps/76.11.1556}, abstractNote={The hypothesis was tested that increased partial pressure of oxygen during the plateau (25 to 26 d of incubation for turkeys) and paranatal (27 to 28 d of incubation) stages of incubation may increase survival rates of turkeys from selected genetic lines. Partial pressure of oxygen inside the incubator cabinet was increased to 171 + 3 mm Hg of the barometric pressure during the plateau stage in oxygen consumption and compared to ambient oxygen (152 + 3 mm Hg). Turkey embryos from genetic lines selected for egg production (E) or growth (F) were compared to their respective randombred controls. These genetic lines have previously been shown to differ in egg weight, eggshell conductance, length of incubation period, embryonic gluconeogenesis, and survival rates during late incubation. Blood, liver, heart, and pipping muscle samples were obtained prior to pipping, at internal pipping and external pipping, and at hatching. The blood was analyzed for glucose concentration and the remaining tissues were assayed for glycogen concentrations. Survival rates were determined on approximately 2,200 eggs in each of three independent trials of the experiment. Interactions of oxygen treatment and genetic line were observed for embryonic survival, heart growth, and hepatic glycogen content. The data suggest that the response to increased oxygen tension in selected genetic lines has been diminished. It was concluded that embryos have been altered metabolically by genetic selection and the concomitant increase in mortality of selected lines during the plateau and paranatal stages is not simply the result of shell quality and hypoxia.}, number={11}, journal={POULTRY SCIENCE}, author={Christensen, VL and Donaldson, WE and Nestor, KE}, year={1997}, month={Nov}, pages={1556–1562} }
 @article{knowles_donaldson_1997, title={Lead disrupts eicosanoid metabolism, macrophage function, and disease resistance in birds}, volume={60}, ISSN={["0163-4984"]}, DOI={10.1007/BF02783306}, abstractNote={Lead (Pb) affects elements of humoral and cell-mediated immunity, and diminishes host resistance to infectious disease. Evidence is presented supporting a hypothesis of Pb-induced immunosuppression stemming from altered fatty acid metabolism, and mediated by eicosanoids and macrophages (MO). Chronic Pb exposure increases the proportion of arachidonate (ArA) among fatty acids in lipid from avian tissues, and this change provides precursors for eicosanoids, the oxygenated derivatives of ArA that mediate MO acute inflammatory response. In the current study, we showed that the concentration of ArA in phospholipids of MO elicited from turkey poults fed 100 ppm dietary Pb acetate was twice that of controls. In vitro production of eicosanoids by these MO was substantially increased, and this effect was most pronounced following lipopolysaccharide stimulation: prostaglandin F2 alpha was increased 11-fold, thromboxane B2 increased threefold, and prostaglandin E2 increased by 1.5 times. In vitro phagocytic potential of these MO was suppressed, such that the percentage of MO engulfing sheep red blood cell (RBC) targets was reduced to half that of control MO. In vivo susceptibility of Pb-treated and control birds to Gram-negative bacteria challenge was also evaluated. The morbidity of chicks inoculated with Salmonella gallinarum and fed either control or 200 ppm Pb acetate-supplemented diets was similar, except early in the course of the disease when mortality among Pb-treated birds was marginally greater. In these studies, effects of Pb that could influence immunological homeostasis were demonstrated for MO metabolism of ArA, for production of eicosanoids, and for phagocytosis. There was also the suggestion that these in vitro indices of immune function are related to in vivo disease resistance.}, number={1-2}, journal={BIOLOGICAL TRACE ELEMENT RESEARCH}, author={Knowles, SO and Donaldson, WE}, year={1997}, pages={13–26} }
 @article{donaldson_christensen_garlich_mcmurtry_olson_1995, title={Exposure to excessive carbon dioxide: A risk factor for early poult mortality}, volume={4}, DOI={10.1093/japr/4.3.249}, abstractNote={Abstract Newly hatched, unfed turkey poults are exposed to several post-hatch stressors, each of which can increase the risk of early mortality. The know risk factors for early poult mortality (e.g., hatchery servicing stressors, prolonged holding without feed or water, temperature stress) all are associated with lower than normal carbohydrate (glycogen) reserves and increased reliance on gluconeogenesis (conversion of non-carbohydrates such as protein to glucose, and the poults sole source of carbohydrate prior to feeding). Sub-standard ventilation conditions during holding, transport, or brooding of poults are considered stressful because carbon dioxide levels rise (hypercapnia). Poults were exposed to elevated 0.4%) CO2 for 16 hr posthatch. We conclude from the metabolic effects observed that hypercapnia is a stressor and thus may be an additional risk factor for early poult mortality.}, number={3}, journal={Journal of Applied Poultry Research}, author={Donaldson, W. E. and Christensen, V. L. and Garlich, J. D. and McMurtry, J. P. and Olson, N. C.}, year={1995}, pages={249} }
 @article{donaldson_christensen_1995, title={Possible toxic effects of gentamicin in newly hatched turkey poults}, volume={4}, DOI={10.1093/japr/4.3.271}, abstractNote={Abstract When poults hatch, they have limited carbohydrate reserves. Hatchery servicing (cloacal sexing, desnooding, beak and toe trimming, and injections) depletes those reserves and places the poults at increased risk of early mortality. Hatchery injections frequently include gentamicin to control bacterial infections in newly hatched turkey poults. In the experiments reported here, gentamicin injections decreased the activities of glucose-6-phosphatase (G-6-Pase) and phosphoenolpyruvate carboxykinase (PEPCK) - both gluconeogenic enzymes - and increased muscle lactate concentration. Both results are consistent with lowered gluconeogenic capacity. The increased concentration of plasma uric acid and the reduced clearance of phenol red from the blood in gentamicin-injected poults are indications of impaired kidney function. The results suggest that the use of gentamicin injections (1 mg/poult) in newly hatched turkeys may be detrimental and could be a risk factor for early poult mortality.}, number={3}, journal={Journal of Applied Poultry Research}, author={Donaldson, W. E. and Christensen, V. L.}, year={1995}, pages={271} }
 @article{donaldson_christensen_ferket_1994, title={Administration of Propionate to Day-Old Turkeys}, volume={73}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps.0731249}, DOI={10.3382/ps.0731249}, abstractNote={The effects of salts of propionic acid on newly hatched turkeys were examined. In Experiment 1, poults were injected with .25 mL of 1 M solutions of either sodium propionate or calcium propionate. After a 24-h holding period, the poults were killed and assayed for blood glucose, liver weight, and liver glycogen. Sodium propionate increased blood glucose concentration but did not alter liver weight or liver glycogen compared with controls. Calcium propionate had no effect on blood glucose but increased liver weight and liver glycogen compared with controls. There was no mortality in saline-injected controls or sodium propionate poults; 4 of 10 poults injected with calcium propionate died. In Experiment 2, poults were administered 0 or 4% sodium propionate in the feed or 0 or 2% sodium propionate in the drinking water in a 2 x 2 factorial arrangement. Propionate depressed feed intake and body weight by both routes of administration. Propionate in the feed, but not drinking water, depressed liver weight and liver glycogen. Plasma uric acid was increased by propionate in either the feed or the water but was not above control amounts when propionate was given in both the feed and water at the same time. Plasma propionic acid was increased by propionate in the water but not by propionate in the feed. We conclude that the use of propionate in injectibles, drinking water, or feed of newly hatched turkeys is contraindicated.}, number={8}, journal={Poultry Science}, publisher={Elsevier BV}, author={Donaldson, W.E. and Christensen, V.L. and Ferket, P.R.}, year={1994}, month={Aug}, pages={1249–1253} }
 @article{donaldson_clark_christensen_1994, title={PROTEIN, LIPID AND GLYCOGEN STORES IN NEWLY-HATCHED TURKEY (MELEAGRIS-GALLOPAVO) POULTS AS AFFECTED BY POSTHATCH STRESSORS AND HOLDING TIME}, volume={107}, ISSN={["0300-9629"]}, DOI={10.1016/0300-9629(94)90040-X}, abstractNote={The effects of post-hatch Stressors (commercial hatchery services which included cloacal inspection to determine sex, snood removal, and beak and toe trimming) and length of holding without feed or water (24 or 48 hr) on carcass and yolk sac contents of moisture, protein, and lipid in turkey poults were studied. In a separate experiment, the effects of the above Stressors and holding (48 hr) on carcass glycogen were measured. Both Stressors and holding reduced carcass weight and absolute moisture content. The per cent carcass moisture declined with holding in stressed but not in non-stressed poults. Stressors lowered the absolute amount of carcass protein but not carcass lipid. Holding lowered absolute amounts of both carcass protein and lipid. Stressors had no effect on absolute amounts of nutrients in yolk. Yolk weight and total protein, lipid, and moisture declined with holding, but the changes were such that percentage moisture was higher at 48 hr. Both glycogen concentration and total glycogen in carcass declined with 48 hr holding, but Stressors were without effect.}, number={3}, journal={COMPARATIVE BIOCHEMISTRY AND PHYSIOLOGY A-PHYSIOLOGY}, author={DONALDSON, WE and CLARK, J and CHRISTENSEN, VL}, year={1994}, month={Mar}, pages={559–562} }
 @article{donaldson_1993, title={EFFECTS OF DIETARY LEAD, FISH OIL, AND ETHOXYQUIN ON HEPATIC FATTY-ACID COMPOSITION IN CHICKS}, volume={36}, ISSN={["0163-4984"]}, DOI={10.1007/BF02783965}, number={3}, journal={BIOLOGICAL TRACE ELEMENT RESEARCH}, author={DONALDSON, WE}, year={1993}, month={Mar}, pages={319–326} }
 @article{donaldson_brewer_ferket_christensen_1992, title={Posthatch Carbohydrate Feeding and Subsequent Performance of Turkey Poults}, volume={71}, ISSN={0032-5791}, url={http://dx.doi.org/10.3382/ps.0710128}, DOI={10.3382/ps.0710128}, abstractNote={In two floor pen trials, day-old poults were fed a low-protein (18.6%) diet for the first 24 or 48 h compared with control poults fed a 28% protein diet. Beyond these initial treatments, all poults were treated identically and were fed the normal progression of starter, grower, and finisher diets to market weight. The treatments did not alter market age body weight or feed conversion. Early mortality and feed intake during the first 48 h were unaffected by the treatments. Feeding the low-protein diet for 24 h enhanced liver glycogen reserves compared with the control. In a battery cage trial, diets containing 50, 33, or 15% available carbohydrate (20, 28, or 35% crude protein, respectively) were fed for 24 h posthatch. The diets had no effect on blood glucose level, but liver glycogen concentration increased with increasing dietary carbohydrate. The results clearly indicate that carbohydrate metabolism is altered by posthatch dietary carbohydrate level. The results also suggest that the dietary protein requirement during the first 24 or 48 h posthatch may not be as high as it is currently thought to be.}, number={1}, journal={Poultry Science}, publisher={Elsevier BV}, author={Donaldson, W.E. and Brewer, C.E. and Ferket, P.R. and Christensen, V.L.}, year={1992}, month={Jan}, pages={128–132} }
 @article{donaldson_1990, title={LIPID-METABOLISM IN LIVER OF CHICKS - RESPONSE TO FEEDING}, volume={69}, ISSN={["0032-5791"]}, DOI={10.3382/ps.0691183}, abstractNote={Fatty-acid synthase is an enzyme complex responsible for the synthesis of the carbon chain of fatty acids. The hepatic activity of this enzyme increases rapidly during a refeeding period following a fast. The activity of fatty-acid synthase in liver of newly hatched chicks rises in parallel with the activities of other lipogenic enzymes at the initiation of feeding. Cycloheximide, an inhibitor of protein synthesis, prevents the feeding-associated rise of other lipogenic enzymes, but not of fatty-acid synthase. Evidence is reviewed that supports the hypothesis that in fasted chicks as well as in unfed, newly hatched chicks, fatty-acid synthase exists in a catalytically less-active form, one that is activated in response to feeding.}, number={7}, journal={POULTRY SCIENCE}, author={DONALDSON, WE}, year={1990}, month={Jul}, pages={1183–1187} }
 @article{donaldson_mcgowan_1989, title={LEAD TOXICITY IN CHICKENS - INTERACTION WITH TOXIC DIETARY LEVELS OF SELENIUM}, volume={20}, ISSN={["0163-4984"]}, DOI={10.1007/BF02919105}, abstractNote={Two experiments were conducted in which varying levels of lead (up to 2000 ppm as lead acetate trihydrate) and selenium (up to 40 ppm as Na2SeO3) were fed, either alone or in combination, to chicks from day-old through 18 or 20 d. Lead additions depressed growth in a dose-dependent manner without affecting mortality. Selenium addition at 20 ppm was severely growth inhibitory, but mortality was not affected. The growth inhibition of 20 ppm Se was partially alleviated by feeding it in combination with 2000 ppm Pb; however, mortality was increased significantly by the combination. In contrast 40 ppm Se resulted in almost complete cessation of growth and 85% mortality, whereas the combination with 2000 ppm Pb partially overcame the growth inhibition and eliminated the excess mortality. When Pb or Se were fed alone, hepatic levels of the fed element were elevated. There were further significant elevations of hepatic levels of both elements when fed in combination at identical dietary concentrations as the single element additions. The results suggest that Pb and Se are antagonistic. The nature of the interaction of these elements is such that although 2000 ppm Pb partially overcomes the growth inhibition by 20 or 40 pm Se, the reverse (relief of Pb inhibition by Se) is not observed.}, number={1-2}, journal={BIOLOGICAL TRACE ELEMENT RESEARCH}, author={DONALDSON, WE and MCGOWAN, C}, year={1989}, pages={127–133} }