- College Park, Maryland, United States
Roselina Angel
University of Maryland, Animal Sciences, Faculty Member
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Diet and Feed Management Practices affect Air Quality from Poultry and Swine Operations by Todd J. Applegate, Brian Richert, and Alan Sutton - Purdue University Wendy Powers, Michigan State University Roselina Angel University of... more
Diet and Feed Management Practices affect Air Quality from Poultry and Swine Operations by Todd J. Applegate, Brian Richert, and Alan Sutton - Purdue University Wendy Powers, Michigan State University Roselina Angel University of Maryland, College ... 2001; Hankins, et al. ...
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The fastest proportional growth of the skeletal system, both in terms of bone length and width as well as mineral deposition, occurs in the first two to three weeks of life. At hatch, mineralization of the skeleton is poor at best. This... more
The fastest proportional growth of the skeletal system, both in terms of bone length and width as well as mineral deposition, occurs in the first two to three weeks of life. At hatch, mineralization of the skeleton is poor at best. This means that during the first few days after hatch a high proportion of the consumed and available minerals are needed for bone mineralization and growth. Yet feed consumption during that period is low and highly variable between birds. This presents a challenge for delivery of critical nutrients for skeletal growth, especially when the problem is compounded by management programs that reduce growth to decrease the incidence ascites and overall leg problems. These strategies often involve lighting programs that reduce feed consumption and thus growth but with minimal or no changes in diet nutrient concentration have been made. Embryo mineral content. There are several excellent articles that review mineral metabolism in avian embryos (Richards and Pack...
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Research Interests: Vitamin D, Phosphorus, Seasonality, Poultry, Manure, and 4 moreinorganic P, Laying hen, Feed Additive, and Organic Acid
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ABSTRACT A total of 4,800 one day (d) old Cobb 500 male broilers was used in a study with the objective of evaluating dietary programs formulated with different degrees of restriction in crude protein (CP) and the supplementation of... more
ABSTRACT A total of 4,800 one day (d) old Cobb 500 male broilers was used in a study with the objective of evaluating dietary programs formulated with different degrees of restriction in crude protein (CP) and the supplementation of L-valine and L-isoleucine. Four feeding programs (PRG) reflecting different strategies to deliver amino acids (AA) to broilers were used, respectively from d 1 to 7, 8 to 21, 22 to 35 and 36 to 42, as follow: PRG 1, CP restricted to 224, 211, 198 and 184 g/kg with minimum digestible AA to lysine (Lys) ratios only set for total sulfur AA (TSAA) (0.72) and threonine (Thr) (0.65); PRG 2, as PRG 1 without CP restriction with AA ratios to Lys extended to valine (Val) (0.77) and isoleucine (Ile) (0.67); PRG 3, as PRG 2 supplemented with L-Val and PRG 4, as PRG 3 supplemented with L-Ile. Replications of the 4 PRG provided from 1 to 21 d were further divided into the 4 respective PRG given from 22 to 42 d for total of 16 treatments. The study was conducted as a completely randomized block design with 2 time blocks and 24 replications per treatment per block from 1 to 21 d and 12 replications from 22 to 42 d. Overall, there were no effects for time block or interaction between PRG fed from 1 to 21 and 22 to 42 d of age. Performance and processing data demonstrated benefits of formulating diets using minimum ratios of Val and Ile. Body weight gain was higher when both AA were supplemented together (PRG 4). On the other hand, feed conversion ratio (FCR) was improved when the ratios Val and Ile to Lys were obtained without the use of synthetic sources. Carcass yield data was not affected by PRG with the exception of the proportion of abdominal fat that was reduced (P < 0.05) when broilers were fed diets with minimum ratios of Val and Ile without using synthetic sources. In conclusion, formulation of diets for broilers without minimum CP level but using AA to Lys ratios as in PRG 2, 3 and 4, allowed competitive growth performance and carcass yield results. Using L-Val and L-Ile led to improved FCR and, therefore, this possibility should be explored to maintain the efficiency of broiler meat production.
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The current study was conducted to evaluate the impacts of using tibia ash percentage or ash weight as the response criteria on estimated phytase relative equivalence. Straight run broilers were fed treatment (Trt) diets from 7 to 21 d... more
The current study was conducted to evaluate the impacts of using tibia ash percentage or ash weight as the response criteria on estimated phytase relative equivalence. Straight run broilers were fed treatment (Trt) diets from 7 to 21 d age (6 birds/pen, 8 pens/Trt). The corn-soy based Trt were formulated to contain 0.80% Ca and 4 non-phytate phosphorus (nPP) concentrations (0.20, 0.27, 0.34, and 0.40%). Monocalcium phosphate was the inorganic phosphate source added to achieve 4 different dietary nPP concentrations and against which the nPP relative equivalence of phytase was determined. A 6-phytase (Danisco Animal Nutrition, DuPont Industrial Biosciences, Marlborough, UK) was added at 500 or 1,000 phytase unit ( FTU: )/kg to the 0.20% nPP diet resulting 6 total Trts. Tibia ash was determined at 21 d age. Phytase fed at 500 or 1,000 FTU/kg increased tibia ash weight and ash percentage compared to that of birds fed 0.20% nPP diet without phytase (P < 0.05). Graded nPP were log tran...
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Rats are a common model for the study of bone healing, with the cranium, femur, and tibia being the bones studied most frequently. This study examines noncritical-sized lesions that would allow rats to continue to bear weight without the... more
Rats are a common model for the study of bone healing, with the cranium, femur, and tibia being the bones studied most frequently. This study examines noncritical-sized lesions that would allow rats to continue to bear weight without the need for fixation but that are sufficiently large to enable characterization of the healing process. We compared the femoral bone strength associated with 3 lesion sizes selected for use in future studies. Sprague-Dawley rats (age, 10 to 16 wk) were used to assess the ultimate breaking strength, stress, and break force of normal, unmanipulated femurs. We then created lesions of 3 different sizes in the mid- to distal diaphysis of the left and right femurs and characterized the associated decreases in bone strength. Femurs (n = 85) for this study were collected through tissue sharing from rats used in other acute surgical procedures and were tested by using a 3-point bending flexural materials-testing machine. Our hypothesis was that, as a model for ...
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ABSTRACT The objective of this study was to investigate the effects of maternal dietary Zn, Mn, and Cu sources on egg production, eggshell quality, hatchability, and hatched chick grading. Inorganic sources of Zn, Mn, and Cu (IZMC) as... more
ABSTRACT The objective of this study was to investigate the effects of maternal dietary Zn, Mn, and Cu sources on egg production, eggshell quality, hatchability, and hatched chick grading. Inorganic sources of Zn, Mn, and Cu (IZMC) as zinc sulfate monohydrate (35% Zn), manganese sulfate monohydrate (31% Mn), and copper sulfate pentahydrate (25% Zn) or organic sources of Zn, Mn, and Cu as amino acid-mineral complexes (OZMC) were used. The 3 experimental treatments consisted of diets supplemented with 1) 100, 100, and 10 mg/kg of Zn, Mn, and Cu, respectively, from IZMC (control); 2) 60, 60, and 3 mg/kg of Zn, Mn, and Cu, respectively, from IZMC plus 40, 40, and 7 mg/kg of Zn, Mn, and Cu, respectively, from OZMC (ISO); and 3) a diet with 100, 100, and 10 mg/kg of Zn, Mn, and Cu, respectively, from IZMC as in the control plus 40, 40, and 7 ppm of supplemental Zn, Mn, and Cu from OZMC (on top). Treatments were fed from 22 to 68 wk of age. Each treatment had 10 replications of 20 females and 2 males. Feeding the ISO diet compared with the control diet increased eggshell weight and thickness (P &lt; 0.05) and decreased early embryo mortality (P &lt; 0.01). Feeding the on top diet compared with the control diet resulted in thicker and heavier eggshells (P &lt; 0.05). An improvement in eggshell quality was observed in breeder hens consuming the OZMC-supplemented ISO diet or the on top diet with IZMC.
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An experiment was conducted to document the age-related changes in IgA concentration in the small intestine of newly hatched turkey poults reared in floor pens and to determine whether infection with stunting syndrome (SS) affects... more
An experiment was conducted to document the age-related changes in IgA concentration in the small intestine of newly hatched turkey poults reared in floor pens and to determine whether infection with stunting syndrome (SS) affects age-related changes. Day-old turkey poults were dose per os with .5 mL of saline carrier (control) or with .5 mL of one of two dilutions (250- or 2.5 x 10(6)-fold) of a "crude" SS-causing inoculum. Inoculation with the 250-fold dilution depressed body weight gain (P less than .01) throughout the experiment and impaired feed efficiency (P less than .05) at 5 and 9 days of age as compared with the control group. After 9 days of age, all inoculated poults utilized feed more efficiently than did control poults (P less than .01). Stunting syndrome did not affect IgA concentrations in either bile or jejunum at any specific age. Age-related changes in IgA concentrations, however, were observed. Bile IgA decreased from 1 to 9 days of age, and then increa...
Research Interests: Poultry Science, Aging, Biology, Medicine, Animal Production, and 7 moreAnimals, Male, Jejunum, POULTRY DISEASES, Food Sciences, Bile, and Turkeys
... Environ. Microbiol. 63:16961700. Abstract/FREE Full Text. Wyss, M., L. Pasamontes, R. Remy, J. Kohler, E. Kusznir, M. Gadient, F. Muller, and A. van Loon. 1998. ... J. Anim. Sci. 81:474483. Abstract/FREE Full Text. ↵ Dilger, RN, EM... more
... Environ. Microbiol. 63:16961700. Abstract/FREE Full Text. Wyss, M., L. Pasamontes, R. Remy, J. Kohler, E. Kusznir, M. Gadient, F. Muller, and A. van Loon. 1998. ... J. Anim. Sci. 81:474483. Abstract/FREE Full Text. ↵ Dilger, RN, EM Onyango, JS Sands, and O. Adeola. 2004. ...
Nutrient mass balances were determined for turkeys fed 4 diets in a 2 × 2 factorial design to investigate the effects of diets with 100 or 110% of NRC (1994)-recommended amino acid (AA) formulation and diets containing 2 (Lys and Met) or... more
Nutrient mass balances were determined for turkeys fed 4 diets in a 2 × 2 factorial design to investigate the effects of diets with 100 or 110% of NRC (1994)-recommended amino acid (AA) formulation and diets containing 2 (Lys and Met) or 3 (Lys, Met, and Thr) supplemental AA. Hybrid tom turkeys were raised and monitored in 12 rooms (3 replicates/diet; 20 toms/room at hatch, culled to 16 at 21 d and then to 12 at 28 d of age). All feed and litter entering and leaving the rooms were quantified and analyzed for nutrient content. Air emissions were measured throughout the 20-wk study. The 100% NRC diets resulted in lower cumulative loss of NH(3) (by 14%) and H(2)S (by 21%) as compared with the 110% NRC diets. Reductions corresponded to lower N and S intake. Feeding the 3 supplemental AA diets resulted in lower N excretion (by 12%) and lower cumulative loss of NH(3) (by 23%) as compared with the 2 supplemental AA diets. The NH(3) emission as a percentage of N output was not significantly...
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The use of exogenous enzymes in feeds for poultry has increased dramatically between 1990 and 2013. Today, the use of enzymes is broad, going beyond phytases and β-glucanases and xylanases to include other carbohydrases and proteases as... more
The use of exogenous enzymes in feeds for poultry has increased dramatically between 1990 and 2013. Today, the use of enzymes is broad, going beyond phytases and β-glucanases and xylanases to include other carbohydrases and proteases as well as lipases. The number of scientific articles and publications related to enzymes in feed clearly shows that this has been an area of intense and broad interest for scientists and nutritionists. However, knowledge of the different substrates available in the feed and how these substrates change depending on feed ingredient selection has not received the same level of attention. Understanding substrates is key to better developing and implementing exogenous enzymes. Of importance today is to potentiate endogenous digestive capabilities and use exogenous enzymes to optimize nutrient digestion and use. Our aim with this symposium was to call attention to the importance of having a more in-depth knowledge about substrates and to fill the large gaps ...
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A study was done to determine whether broilers can regulate Ca intake when limestone is provided separately or mixed with a crumbled feed of variable Ca and P content, and the influence of this on performance and apparent ileal... more
A study was done to determine whether broilers can regulate Ca intake when limestone is provided separately or mixed with a crumbled feed of variable Ca and P content, and the influence of this on performance and apparent ileal digestibility (AID) of Ca and P (AIDP). Twelve crumbled diets were fed from 10 to 20 d of age (8 replicates, 8 broilers/replicate). Diets A to D contained 0.28% nonphytate P (nPP) and 0.27, 0.51, 0.77, and 1.02% Ca, respectively. Diets E to H contained 0.48% nPP and 0.41, 0.51, 0.77, and 1.02% Ca, respectively. A large particle size limestone was mixed manually to the crumbled diet on a daily basis to achieve 1.02% total Ca in diets A to H. Diets I to L had the same Ca and nPP as diets A to D, but limestone was provided in a separate feeder to assess spatial importance of limestone supply. Limestone consumption, provided in a separate feeder, decreased as Ca concentration increased in the crumble diet (P < 0.05). Calcium intake increased as Ca concentratio...
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The recent technologies that have led to the new field of functional genomics (how the genome of an organism regulates homeostasis and responds to stimuli) are providing a clearer understanding of how organisms interact with their... more
The recent technologies that have led to the new field of functional genomics (how the genome of an organism regulates homeostasis and responds to stimuli) are providing a clearer understanding of how organisms interact with their environment and in particular their diet. We are beginning to learn how the diet may have long-term influence on performance and health. A form of epigenetic regulation has been recently described called fetal "programming". Fueled by epidemiological data the "fetal origins" hypothesis suggests that a poor in utero environment resulting from maternal dietary or placental insufficiency may "program" susceptibility in the fetus to cardiovascular or metabolic disorders. We have observed similar apparent programming by dietary manipulation in the chicken. When birds are challenged with a diet low in phosphorus (P) for 90 hours post-hatch they obtain the ability to better utilize P later in life. This increased retention of P from ...
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Effects of dietary adipic acid (0 vs. 1%) and corn dried distillers grains with solubles (DDGS; 0 vs. 20%) were evaluated on hen performance and egg characteristics from 26 to 34 wk of age. Four isocaloric and isonitrogenous diets were... more
Effects of dietary adipic acid (0 vs. 1%) and corn dried distillers grains with solubles (DDGS; 0 vs. 20%) were evaluated on hen performance and egg characteristics from 26 to 34 wk of age. Four isocaloric and isonitrogenous diets were randomly assigned to blocks of 6 consecutive cages (36 cages per diet; 2 hens per cage). On wk 2 and 7 of the experiment, excreta were collected by cage block, mixed, and equally split into 2 containers. Sodium bisulfate (SBS) was spread (8.8 kg/100 m(2)) on the top surface of half of the containers. All containers were stored uncovered for 14 d at room temperature. Excreta pH, DM, and N content were measured on d 0, 7, and 14 of storage. Feed intake (112 g/d per hen), egg production (96.1%), and egg specific gravity (1.079 g/g) were not affected by diet. On excreta collection day, a synergy (P = 0.014) between dietary adipic acid and DDGS was detected, as the lowest excreta pH was obtained with the diet including both adipic acid and DDGS. On d 7 of storage, excreta pH was still reduced by dietary adipic acid (P = 0.046) and DDGS (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001), but a week later, only dietary DDGS decreased excreta pH (8.91 vs. 9.21; P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001). Whereas dietary adipic acid had no influence on excreta N loss, excreta from hens fed 20% DDGS lost 19.7% more N (P = 0.039) during storage than hens not eating DDGS. Surface amendment of excreta with SBS increased excreta DM content, with the effect being even more marked on d 14 of storage (increase of 6.7 percentage units; P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001), consistently decreased excreta pH during storage (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.001) and reduced N loss by 26.1% for the 14 d of storage period.
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Two experiments were conducted to evaluate the effect of virginiamycin (VM, 22 mg/kg of diet) on performance of uninfected (CON) turkey poults and those infected (INO) with stunting syndrome and reared on used woodshavings (Experiment 1)... more
Two experiments were conducted to evaluate the effect of virginiamycin (VM, 22 mg/kg of diet) on performance of uninfected (CON) turkey poults and those infected (INO) with stunting syndrome and reared on used woodshavings (Experiment 1) or on clean or used woodshavings (Experiment 2). Virginiamycin improved BW (P less than .001) and feed efficiency (FE) (P less than .05) from 1 to 29 days of age, irrespective of type of litter or disease condition. The increase in BW induced by VM, however, was greatest when poults were kept on used litter, resulting in significant (P less than .05) VM by litter interaction. Induced stunting syndrome depressed BW (P less than .01) to 29 days of age and impaired FE from 1 to 9 days of age (P less than .05) and from 5 to 9 days of age (P less than .01) in Experiments 1 and 2, respectively. Virginiamycin did not prevent early adverse effects of INO on BW and FE, but facilitated notable recovery of INO poults relative to INO poults not fed VM. Virginiamycin increased specific activities of maltase and sucrase of the jejunum of CON poults in Experiments 1 and 2; in Experiment 2, this VM effect was evident irrespective of type of litter. Maltase-specific activity and sucrase were reduced by INO (P less than or equal to .05 and P less than or equal to .01 in Experiments 1 and 2, respectively) and VM did not modify this effect. The maltase and sucrase data suggest that VM improved BW and FE of CON poults, in part, by helping to maintain digestive and absorptive functions of the small intestine during the early growth period, but, in the instance of INO poults, VM was not effective in this regard.
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Experiments were done to determine the effect of feeding diets of different ingredient composition to poults experimentally infected with stunting syndrome (SS) at 1 day of age. In Experiment 1, feeding a complex diet (CPX) containing... more
Experiments were done to determine the effect of feeding diets of different ingredient composition to poults experimentally infected with stunting syndrome (SS) at 1 day of age. In Experiment 1, feeding a complex diet (CPX) containing fish meal and sunflower meal as the main protein sources eliminated the adverse effects of SS inoculation on performance traits as compared with SS effects on poults fed a corn and soybean meal (CS) diet. In Experiments 2 and 3, the effects of SS were more severe than in Experiment 1. In these experiments, the CPX diet only partly overcame the adverse effects of SS on performance (i.e., in Experiment 2, growth depressions from 2 to 5 days of age were 90.3 and 59.6% in SS-inoculated poults fed the CS and CPX diets, respectively, as compared with uninoculated, control poults fed the same diets). Properties of the CPX diet that made it effective in reducing the severity of SS were not evident from the results of Experiment 3. Replacing soybean meal with soy protein or canola meal was ineffective as compared with the use of a mixture of sunflower meal, fish meal, meat and bone meal, and corn gluten meal.
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Experiments were conducted to determine the effect of an induced enteric disorder, stunting syndrome (SS), on young turkeys. One-day-old poults were dosed per os with tryptose-phosphate broth (control) or inoculum (inoc) prepared from... more
Experiments were conducted to determine the effect of an induced enteric disorder, stunting syndrome (SS), on young turkeys. One-day-old poults were dosed per os with tryptose-phosphate broth (control) or inoculum (inoc) prepared from intestines of SS-affected poults. Inoculation depressed gain (P less than .001) and feed consumption (P less than .001) and impaired (P less than .001) the utilization of feed for gain up to 9 days of age (utilization was 2.02, 2.62 in inoc and 1.27, 1.61 in control poults at 5 and 9 days of age, respectively). Inoculation impaired (P less than .05) retention of nutrients at 8 days of age (dry matter, fat, protein, and ash retentions were 82.5, 88.8, 81.3, and 77.8% in controls and 79.3, 85.6, 74.5, and 74.1% in inoc poults, respectively). Small intestinal weight per 100 g of body weight was greater (P less than .001) in inoc poults, but empty weights per length of jejunum and ileum were less (P less than .05). The jejunal mucosa in inoc poults was thinner, exhibited extensive erosion of villi tips, and had microvilli that seemed to be fused when observed by using scanning electron microscopy. Activities of disaccharidases in the jejunum and ileum of inoc poults were less (P less than .05) than in control poults. In a second experiment, two additional treatments were included, a pair-fed control and a negative control. Control poults pair-fed with the inoc poults grew more rapidly (P less than .01) than inoc poults. The depression in feed consumption due to inoculation accounted for only 54% of the growth depression. Poults inoculated with a suspension prepared from intestines obtained from healthy poults (negative control) performed similarly to controls. Thus, the adverse effects of the SS-inoculum were due to an agent(s) that was present int he intestines of SS-affected poults but not in intestines of healthy poults.
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Higher concentrations of Ca in the diet may decrease phytate-phosphorus hydrolysis because of chelation of Ca with the phytin molecule. In experiment 1, drakes were fed 0.74, 0.85, 0.95, or 1.11% Ca (analyzed) from 7 to 18 d of age (6... more
Higher concentrations of Ca in the diet may decrease phytate-phosphorus hydrolysis because of chelation of Ca with the phytin molecule. In experiment 1, drakes were fed 0.74, 0.85, 0.95, or 1.11% Ca (analyzed) from 7 to 18 d of age (6 birds/cage, 8 cages/diet). Intestinal mucosa was collected at 18 d of age from birds fed 0.74 and 1.11% Ca for determination of intestinal phytase activity. In experiment 1, 17 d BW gain and feed consumption exhibited a quadratic response to increasing concentrations of Ca and were found to be maximal for ducks fed the 0.95% Ca diet. Toe ash percentage (18 d) had a quadratic response to increasing concentrations of Ca with a maximal response for birds fed the 0.85% Ca diet. Increasing dietary Ca did not affect P retention from 15 to 17 d of age or intestinal phytase activity and brush border vesicle Ca concentration. A positive correlation was found between the Vmax and the Ca concentration within the vesicles (r = 0.59, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.02), suggesting that the vesicle Ca concentration did not negatively affect the kinetics of the phytase assay. In experiment 2, drakes were fed 0.6, 0.8, 1.0, or 1.2% Ca (formulated) with 826 or 8,260 ICU/kg of vitamin D3 from 0 to 13 d of age. There was no response to increasing concentrations of Ca for performance characteristics or bone ash measurements.
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Developing embryos and hatchling poults were sampled (n = 4) at Days 22, 24, 26, and 28 of incubation and at 1, 2, 4, 6, and 8 days after hatching, and selected characteristics of the gastrointestinal tract (GIT) were measured. Body... more
Developing embryos and hatchling poults were sampled (n = 4) at Days 22, 24, 26, and 28 of incubation and at 1, 2, 4, 6, and 8 days after hatching, and selected characteristics of the gastrointestinal tract (GIT) were measured. Body weight increased linearly up to day of hatching and also from 2 to 8 days posthatching. Residual yolk weight decreased rapidly starting on Day 26 of incubation and was nearly depleted by 4 days posthatching. Changes in weight of segments of the GIT nearly paralleled the increase in body weight until day of hatching. Thereafter, weights of the proventriculus, small intestine, and pancreas increased more rapidly than body weight until 6 days after hatching. At this time, change in weight of small intestine and pancreas seemed to parallel that of body weight, whereas proventriculus weight continued to increase more rapidly. Gizzard weight, as a percentage of body weight, increased until Day 4 posthatching and then remained relatively constant through 8 days. Specific activities (SA) of pancreatic amylase, lipase, and trypsin were low until after hatching. Subsequently, amylase SA increased nearly threefold by Day 6. Lipase SA remained nearly constant between Days 1 and 8, and trypsin SA increased only slightly. Total activities of pancreatic enzymes, however, increased substantially after hatching, mainly because of increased pancreas weight. Jejunal maltase SA was high at hatching but decreased markedly by Day 4. This decrease in SA resulted in a notable reduction in total maltase activity of the jejunum despite an increase in jejunum weight.
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An experiment was conducted to determine the influence of dietary fat on weight of eggs and egg yolks of White Leghorn hens from 24 to 38 wk of age. Beginning at 24 wk of age, nine experimental units of eight hens each were fed one of... more
An experiment was conducted to determine the influence of dietary fat on weight of eggs and egg yolks of White Leghorn hens from 24 to 38 wk of age. Beginning at 24 wk of age, nine experimental units of eight hens each were fed one of five diet treatments. Treatments consisted of a corn-soybean meal diet containing no added fat, diets containing 3 or 6% animal-vegetable fats (A-V fat) formulated to be isocaloric and equinitrogenous with the no added fat diet, and diets containing 3 or 6% A-V fat in which the metabolizable energy (ME) concentration increased 105 kcal/kg with each 3% increment of A-V fat. Weights of eggs, yolks, and whites were measured biweekly. Supplemental A-V fat did not affect rate of egg production, but feed efficiency was improved significantly as ME increased from diets of increasing ME. No effect of A-V fat on egg or yolk weight was observed until after 4 wk of treatment (28 wk of age). From this time through 12 wk of treatment, a linear increase in yolk weight with increments of A-V fat (P less than .01) occurred, irrespective of diet series (isocaloric or increasing ME). Concurrently, there was a nonsignificant (P less than .10) trend for increased egg weight as A-V fat level increased, but weights of egg whites were not affected significantly. Average increases in yolk and egg weights during the period when hens were 28 through 36 wk of age were approximately .5 and 1 g, respectively, when 6% A-V fat was used, irrespective of diet series.(ABSTRACT TRUNCATED AT 250 WORDS)
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The objectives of the study were to evaluate the effectiveness of a reduced-emission (RE) diet containing 6.9% of a CaSO(4)-zeolite mixture and slightly reduced CP to 21-, 38-, and 59-wk-old Hy-Line W-36 hens (trials 1, 2, and 3,... more
The objectives of the study were to evaluate the effectiveness of a reduced-emission (RE) diet containing 6.9% of a CaSO(4)-zeolite mixture and slightly reduced CP to 21-, 38-, and 59-wk-old Hy-Line W-36 hens (trials 1, 2, and 3, respectively) on egg production and emissions of NH(3), H(2)S, NO, NO(2), CO(2), CH(4), and non-CH(4) total hydrocarbons as compared with feeding a commercial (CM) diet. At each age, 640 hens were allocated, randomly to 8 environmental chambers for a 3-wk period. On an analyzed basis, the CM diet contained 18.0, 17.0, and 16.2% CP and 0.25, 0.18, and 0.20% S in trials 1, 2, and 3, and the RE diet contained 17.0, 15.5, and 15.6% CP and 0.99, 1.20, and 1.10% S in trials 1, 2, and 3. Diets were formulated to contain similar Ca and P contents. Average daily egg weight (56.3 g), average daily egg production (81%), average daily feed intake (92.4 g), and BW change (23.5 g), across ages, were unaffected by diet (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; 0.05) over the study period. Age effects were observed for all performance variables and NH(3) emissions (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05). In trials 1, 2, and 3, daily NH(3) emissions from hens fed the RE diets (185.5, 312.2, and 333.5 mg/bird) were less than emissions from hens fed the CM diet (255.1, 560.6, and 616.3 mg/bird; P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01). Daily emissions of H(2)S across trials from hens fed the RE diet were 4.08 mg/bird compared with 1.32 mg/bird from hens fed the CM diet (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01). Diet (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05) and age (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05) affected emissions of CO(2) and CH(4). A diet effect (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.01) on NO emissions was observed. No diet or age effects (P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; 0.05) were observed for NO(2) or non-CH(4) total hydrocarbons. Results demonstrated that diet and layer age influence air emissions from poultry operations.
Research Interests:
The objectives of the current study were to evaluate the effect of an acidifying diet (gypsum) combined with zeolite and slightly reduced crude protein (R) vs. a control diet (C) on nutrient retention in laying hens and compare 3... more
The objectives of the current study were to evaluate the effect of an acidifying diet (gypsum) combined with zeolite and slightly reduced crude protein (R) vs. a control diet (C) on nutrient retention in laying hens and compare 3 approaches to estimating nutrient excretion from hens: 1) mass balance calculation (feed nutrients - egg nutrient), 2) use of an indigestible marker with analyzed feed and excreta nutrient content, and 3) an environmental chamber that allowed for capturing all excreted and volatilized nutrients. Hens (n = 640) were allocated randomly to 8 environmental chambers for 3-wk periods. Excreta samples were collected at the end of each trial to estimate apparent retention of N, S, P, and Ca. No diet effects on apparent retention of N were observed (53.44%, P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;gt; 0.05). Apparent retention of S, P, and Ca decreased in hens fed R diet (18.7, - 11.4, and 22.6%, respectively) compared with hens fed the C diet (40.7, 0.3, and 28.6%, respectively; P &amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;lt; 0.05). Total N excretion from hens fed the C and R diet was not different (1.16 g/hen/d); however, mass of chamber N remaining in excreta following the 3-wk period was less from hens fed the C diet (1.27 kg) than from hens fed the R diet (1.43 kg). Gaseous emissions of NH(3) over the 3-wk period from hens fed the C diet (0.74 kg per chamber) were greater than emissions from hens fed the R diet (0.45 kg). The 3-wk S excretion mass (estimated using the calculation, indigestible marker, and environmental chamber methods, respectively) was greater from hens fed the R diet (1.85, 1.54, and 1.27 kg, respectively) compared with hens fed the C diet (0.24, 0.20, and 0.14 kg, respectively). The 3-wk P excretion was similar between diets (0.68 kg). Results demonstrate that feeding the acidified diet resulted in decreased N emissions, but because of the acidulant fed, greatly increased S excretion and emissions.
Research Interests:
Manure from poultry feeding operations is associated with diminished air quality. The objectives of the current study were to evaluate the effectiveness of feeding a reduced emission diet (R) containing 6.9% of a gypsum- zeolite mixture... more
Manure from poultry feeding operations is associated with diminished air quality. The objectives of the current study were to evaluate the effectiveness of feeding a reduced emission diet (R) containing 6.9% of a gypsum- zeolite mixture and a slightly reduced crude protein (CP) to 21-, 38-, and 59-week-old Hy-Line W-36 hens (trials 1, 2, and 3, respectively) on egg production and emissions of NH 3 , H 2 S, NO, NO 2 , CO 2 , CH 4 and non-methane total hydrocarbon as compared to feeding a commercial diet (C). At each age, 640 hens (body weight = 1.36, 1.47, and 1.52 kg in trials 1, 2, and 3, respectively) were allocated randomly to eight environmental chambers for a 3-week period. On an analyzed basis, the C diet contained 18.0, 17.0, and 16.2% CP and 0.25, 0.20, and 0.20% S in trials 1, 2, and 3, respectively. The R diet contained 17.0, 15.5, and 15.6% CP and 0.99, 1.20, and 1.10% S in trials 1, 2, and 3, respectively. Diets were formulated to contain similar calcium and phosphorus c...
Research Interests:
Modifying broiler diets to mitigate water quality concerns linked to excess phosphorus (P) in regions of intensive broiler production has recently increased. Our goals were to evaluate the effects of dietary modification, using phytase... more
Modifying broiler diets to mitigate water quality concerns linked to excess phosphorus (P) in regions of intensive broiler production has recently increased. Our goals were to evaluate the effects of dietary modification, using phytase and reduced non-phytate phosphorus (NPP) supplementation, on P speciation in broiler litters, changes in litter P forms during long-term storage, and subsequent impacts of diets on P in runoff from litter-amended soils. Four diets containing two levels of NPP with and without phytase were fed to broilers in a three-flock floor pen study. After removal of the third flock, litters were stored for 440 d at their initial moisture content (MC; 24%) and at a MC of 40%. Litter P fractions and orthophosphate and phytate P concentrations were determined before and after storage. After storage, litters were incorporated with a sandy and silt loam and simulated rainfall was applied. Phytase and reduced dietary NPP significantly reduced litter total P. Reducing dietary NPP decreased water-extractable inorganic phosphorus (IP) and the addition of dietary phytase reduced NaOH- and HCl-extractable organic P in litter, which correlated well with orthophosphate and phytic acid measured by 31P nuclear magnetic resonance (NMR), respectively. Although dry storage caused little change in P speciation, wet storage increased concentrations of water-soluble IP, which increased reactive P in runoff from litter-amended soils. Therefore, diet modification with phytase and reduced NPP could be effective in reducing P additions on a watershed scale. Moreover, efforts to minimize litter MC during storage may reduce the potential for dissolved P losses in runoff.