Student Competition: Metabolism and Nutrition, Nutrition I
46 An in vitro technique for measuring the digestion kinetics
of dietary proteins fed to poultry. Dervan D. S. L. Bryan*, Dawn A.
Abbott, and Henry L. Classen, University of Saskatchewan, Saskatoon, SK, Canada.
Obtaining digestion kinetics data for CP ingredients before diet formulation is difficult. An in vitro technique is proposed for measuring
the digestion kinetics of protein sources fed to poultry using a 30-min
gastric and 4-h intestinal phase to mimic digestion in chickens. Protein
sources (500 mg of CP = % N × 6.25) were digested with 0.05 mg
of guar gum, 8.5 mL of 0.1 N HCl, and 1.5 mL of pepsin in 50-mL
polyethylene centrifuge tubes for 30 min in a shaking water bath (150
strokes/min; 30-mm stroke length) at 41°C. After the gastric phase, all
tube pH were adjusted to 7 ± 0.5 with 500 µL of 4.9 N NaOH, 9.5 mL
of sodium acetate buffer (pH 12.5), followed by the addition of 6.5 mL
of pancreatin. Three glass marbles were placed in each tube and all
tubes were incubated in the water bath for 4 h. At 0, 15, 30, 45, 60, 90,
120, 150, 180, and 240 min during the intestinal phase, 0.5-mL aliquots
were collected. Digestion (DIG) was measured calorimetrically via a
ninhydrin assay where aliquots were diluted (1:820) with 10 mL of 0.1
N HCl followed by 10 mL of sodium acetate buffer pH 6.5 and H2O.
Samples were mixed with ninhydrin reagent (2:1) at 100°C ± 2 for 15
min and absorbance read at 568 nm on a spectrophotometer after 10
min of cooling. Each meal CP DIG was calculated over time as meal
aliquots absorbance expressed as a percentage of total absorbance of
meal after 24-h digestion in 6 N HCl at 110°C. To validate the assay, 5
replications per run of soybean (SBM), corn gluten (CGM), and corn
distillers dried grains with solubles (CDDGS) meals were digested in
2 runs. Data were modeled with PROC NLIN procedure and inter and
intra coefficient of variation (CV) assessed with PROC MEANS of SAS
9.4. The DIG values at 150 min were SBM 87 ± 4%, CGM 63 ± 10%,
and CDDGS 60 ± 4%. Intra-assay CV for SBM, CGM and CDDGS
were 3 to 4, 3 to 4, and 2 to 4%, respectively, whereas the inter-assay
CV values were 5, 15, and 4%, respectively. The respective estimated
digestion rates for SBM, CGM and CDDGS were 0.58, 0.42, and 0.40
(%/min). In conclusion, the proposed in vitro technique determined the
rate and extent of digestion for the meals while achieving low intra- and
inter-assay variability.
Key Words: in vitro, digestion kinetics, soybean meal, corn gluten
meal, corn distillers grains
47 Effects of modifying diet and feed manufacture concern
areas that are notorious for decreasing pellet quality. Tyler R.
Rigby*, Brian G. Glover, Kolby L. Foltz, and Joseph S. Moritz, West
Virginia University, Morgantown, WV.
The production of high quality pellets has often been described as more
art than science due to the multitude of variables that affect pellet quality.
Variables may interact with one another to exacerbate negative effects
on the pelleting process. The objectives of the current study were to
examine the feed manufacture and pellet quality effects of 4 different
feed milling concern areas utilizing semi-wet corn (>15% moisture)
in all formulations. Each area of concern was evaluated using either a
condition of high concern or a corresponding condition of low concern.
Treatments included high or low mixer added fat (2.5 vs. 0.5%), high
or low distillers dried grains with solubles (DDGS; 8 vs. 2%), high
or low dicalcium phosphate (1.63 vs. 0.31%), and high or low steam
conditioning temperature (82 vs. 74°C). All diets were formulated to
16
similar broiler starter requirements based on commercial nutrient values.
A randomized complete block design using a 4 × 2 factorial arrangement was implemented with 3 replications per treatment and 136-kg
allotments of feed as the experimental unit. Contrasts were performed
to better understand main effect interactions. Semi-wet corn was analyzed to contain 16.6% moisture. Area of concern and level of concern
interacted to effect pellet durability, percent pellets, and particle size (P
< 0.05). High mixer added fat and low dicalcium phosphate decreased
pellet durability, percent pellets, and feed particle size (P < 0.05). Conditions of high concern for DDGS and steam conditioning did not produce
similar negative effects (P > 0.05). Pellet production rate, conditioner
electrical energy usage, and pellet mill electrical energy usage were not
affected by treatments (P > 0.05), likely due to semi-wet corn inhibiting opportunities for treatments to improve lubrication at the mash die
interface. A greater appreciation of variable interactive effects benefits
pellet mill operators, nutritionists, and pelleting aid vendors to better
circumvent hurdles encountered during the pelleting process.
Key Words: pellets, fat, DDGS, dicalcium phosphate, steam
conditioning
48 Maternally derived anti-fibroblast growth factor 23 antibody as new tool to reduce phosphorus requirement of chicks.
Zhouzheng Ren*, Daniel E. Bütz, Jordan M. Sand, and Mark E.
Cook, Department of Animal Sciences, University of WisconsinMadison, Madison, WI.
Novel means to reduce phosphate input into poultry feeds and increase
its retention would preserve natural reserves and reduce the environmental effect of poultry production. Here, we show that a maternally
derived antibody to a fibroblast growth factor-23 (FGF-23) peptide
(GMNPPPYS) alleviated phosphorus deficiency in chicks fed low
non-phytate phosphorus (nPP, 0.13 and 0.20%) diets. White Leghorn
laying hens were vaccinated with either an adjuvant control or the
synthetic FGF-23 peptide, and chicks with control or anti-FGF-23
maternal antibodies were fed a diet containing either 0.13 or 0.45%
nPP (experiment 1), and 0.20 or 0.45% nPP (experiment 2) for14 d. In
both experiments, independent of maternal FGF-23 antibody, decreasing nPP from 0.45 to 0.13 or 0.2% decreased (P < 0.05) body weight
(>15%), feed efficiency (>20%), tibia ash (>12%), excreta phosphorus
(>22%), plasma phosphorus (>28%) and plasma FGF-23 (>17%). In
experiment 1, chicks with maternal anti-FGF-23 antibody had increased
bone ash (10.5%), and decreased excreta phosphate (7.4%) compared
with chicks with control antibody (main effects, P < 0.05). In addition,
mortality, posture scores and bone lesion scores were decreased and
plasma phosphate increased (2 fold) in anti-FGF-23 chicks fed 0.13%
nPP, compared with those with control antibody on the same diet (P <
0.05). In experiment 2, chicks with maternal anti-FGF-23 antibody had
decreased excreta phosphate (4.4%, P = 0.064) and increased plasma
phosphate (13.7%) and plasma 1,25 (OH)2D3 (20.4%) compared with
chicks with control antibody (main effects, P < 0.05). In addition, body
weight (24.7%) and feed efficiency (46.2%) was increased in chicks
with maternal anti-FGF-23 fed 0.20% nPP, compared with those with
control antibody on the same diet (P < 0.001). In conclusion, maternally
derived anti-FGF-23 antibody reduced signs of phosphorus deficiency
in chicks fed diets containing either 0.13 or 0.20% nPP, probably by
way of increased phosphorus retention.
Key Words: FGF-23, antibody, phosphorus, requirement, chick
Poult. Sci. 95(E-Suppl. 1)
49 Split feeding as an alternative system to improve shell quality of aged hens. Anikó Molnár*1,2, Luc Maertens1, Johan Buyse3,
Johan Zoons2, and Evelyne Delezie1, 1Institute for Agricultural and
Fisheries Research, Melle, Belgium, 2Experimental Poultry Center,
Geel, Belgium, 3KU Leuven, Leuven, Belgium.
In this experiment, we investigated the effect of 5 split feeding treatments on performance and egg quality of individually housed layers
(75–90 wk, Dekalb White, n = 12/treatment). The control treatment
(T1) received the same feed in the morning (M) and in the afternoon
(A), which contained fine (F) and coarse limestone (CLS) at ratio 50:50.
For the split treatments, the ratio of FLS and CLS was 50:50 or 30:70
and time of administration (M/A) differed. The following treatments
were given: T2 = 50CM:50FA, T3 = 30FA:70CA, T4 = 50FM:50CA,
T5 = 30FM:20FA+50CA, and T6 = 30FM:70CA. Data were analyzed
with a linear mixed effects model in R 3.1. Due to an unexpectedly low
feed intake and laying percentage, T1 could not be compared with the
split treatments and was excluded from the analysis. Results indicated
that time of feeding FLS and CLS affect production and shell quality.
When only FLS was fed in the afternoon (T2) shell formation had to
be supported by bone reserves during the night which resulted in low
shell thickness (ST). Although ST decreased in all treatments from
403.2 to 390.2 µm between 76 and 90 wk of age (P = 0.016), highest
ST was obtained in T4 (408.0 µm) and T5 (401.7 µm), whereas ST of
T2 (388.2 µm) and T3 (394.3 µm) was the lowest (P = 0.058). When all
LS was fed in the afternoon (T3), egg weight (EW) increased and ST
decreased. At 88 wk of age, eggs weighed 60.4 g in T2, whereas EW
was 66.3 g in T3 and 67.3 g in T6 at 88 wk (P ≤ 0.05). Providing FLS in
the morning and CLS in the afternoon in ratios of 50:50 (T4), 30:20+50
(T5), or 30:70 (T6), however, resulted not only in favorable shell quality but also performance: laying percentage of hens in T4 (89.6%) and
T5 (92.9%) was higher than in T2 (66.1%) at 89 to 90 wk of age (P ≤
0.05). Laying percentage of T3 (71.7%) was lower than that of T5, and
T6 (86.8%) did not differ from the other treatments. Feed conversion
ratio (FCR) in T2 was higher than in T5, T3, and T6 at 87–88 wk (P ≤
0.05). At 89–90 wk, FCR of T3 increased, and T2 and T3 had a higher
FCR compared with T4, T5 and T6. Therefore, T4, T5, and T6 can be
considered for further research to study whether this feeding system
could also be applied under field conditions.
Key Words: split feeding, egg quality, limestone, aged layer,
performance
50 Evaluation of the lysine requirement of 7- to 28-day-old
Bobwhite quail. Ariel N. Bergeron*, Jose W. Charal, and Theresia A.
Lavergne, LSU Agricultural Center, Baton Rouge, LA.
Two trials were conducted to evaluate the lysine requirement of 7- to
28-d-old Bobwhite quail. A total of 360 Bobwhite quail were used. In
each trial, 180 quail were allotted and placed on 1 of 5 treatment diets
with 6 replications of 6 quail per replicate on d 7 of age. The treatment
diets were formulated to contain 1.33, 1.53, 1.73, 1.93, or 2.13% total
lysine. All diets contained the same amounts of corn and soybean meal,
and various amounts of Biolys (54.6% l-lysine) were substituted for
isonitrogenous amounts of l-glutamic acid. Diets were formulated to
contain 2,900 kcal/kg ME and 4.36% N. Feed and water were provided
ad libitum. Each trial was conducted for 21 d. Quail were weighed at
initiation of the experiment (d 7 of age), at d 14 of age, at d 21 of age,
and at the termination of the experiment (d 28 of age) to determine
body weight (BW), average daily gain (ADG), average daily feed
intake (ADFI), and feed efficiency (GF). In both trials, there were no
differences (P > 0.05) in BW, ADG, ADFI, or GF for quail fed any of
the lysine levels. In the first trial, average BW, ADG, ADFI, and GF
Poult. Sci. 95(E-Suppl. 1)
were 73.97 g, 2.73 g, 6.04 g, and 0.45, respectively. Average BW, ADG,
ADFI, and GF were 59.28 g, 1.82 g, 5.92 g, and 0.32, respectively, in
the second trial. The results of these trials indicate that the NRC (1994)
recommended lysine requirement of 1.73% is adequate for 7- to 28-dold quail. Additional research is needed to determine the exact lysine
requirement of 7- to 28-d-old Bobwhite quail.
Key Words: Bobwhite quail, lysine, average daily gain, average
daily feed intake, feed efficiency
51 Effects of feed form, environment, and caloric density on
energy partitioning and subsequent broiler performance. Brian
G. Glover*, Kolby L. Foltz, Kenneth J. Ryan, and Joseph S. Moritz,
West Virginia University, Morgantown, WV.
Benefits of improved pellet quality on broiler performance have been
well documented. Feed prehensive energy savings acquired from an
improved crumble/pellet percentage could affect dietary caloric requirements. The objective of the study was to assess the effect of variations
of crumble/pellet percentages and dietary caloric density on broilers
reared on clean shavings and built-up litter. All diets were batched,
mixed, steam conditioned to approximately 80°C, extruded through a
4- × 38-mm pellet die, and crumbled at the West Virginia University
pilot feed mill. Bird density and feeder space access was 0.06 m2/bird
and 1.2 cm/bird, respectfully. A split-plot design was used. Whole plot
treatments of clean shavings or built-up litter were randomly assigned
to a room (11 × 7.32 m). The design at the subplot level within room
was a randomized block design with 8 blocks and a 2 × 2 factorial
treatment structure. The subplot treatment structure consisted of either
a standard (30% crumble/pellet) or improved feed form (80% crumble/
pellet), and either standard or increased (+110 kcal/kg) caloric density.
Study replication allowed testing for the presence of room effect at the
whole plot level. The main effects of improved feed form and increased
caloric density significantly decreased feed conversion ratio (P < 0.05).
Broilers consuming an improved feed form increased feed intake, live
weight gain, hot breast weight, and visceral fat pad weight (P < 0.05).
A feed form by caloric density 2-way interaction was observed for
visceral fat pad weight and yield responses (P < 0.05) demonstrating
improved crumble/pellet percentage in combination with increased
caloric density provided the most energy on average for storage in the
form of adipose tissue. These data suggest that improvements in feed
form may provide feed prehensive energy savings that could be partitioned to other biological processes.
Key Words: feed form, pellet, broiler, caloric density, crumble
52 Diet induced thermogenesis in broilers: A precision feeding
approach. Sasha A. S. van der Klein*, Chris A. Ouellette, and Martin
J. Zuidhof, Department of Agricultural, Food and Nutritional Science, University of Alberta, Edmonton, AB, Canada.
Understanding individual bird and diet effects on net energy available
for productive processes is the next step in optimal feed formulation. The
aim of this study was to gain insight into factors contributing to energy
lost via heat. We estimated the effect of dietary metabolizable energy
(ME) level and ME intake on ME requirements for maintenance (MEm)
and residual feed intake (RFI). We hypothesized that diets containing
low or high ME would have different rates of associated diet induced
thermogenesis (DIT), and that reduced feed intake would reduce heat
loss, and thus result in a lower RFI. At hatch, 48 Ross 308 broilers were
randomly allocated in 1 of 4 pens, all of which were equipped with a
precision feeding station. Isonitrogenous diets varying in ME content
17
were fed at different levels using a precision feeding station. Pens were
randomly assigned to a high ME (3,150 kcal/kg) or a low ME (2,900
kcal/kg) diet. Birds were trained to use the station as a group from 0 to
10 d of age. At d 10, birds received a radio frequency identification tag
and were transitioned to individual feeding. At d 19, 2 birds per pen were
assigned to ad libitum treatment and used as master birds. The other
birds were randomly coupled to one of the 2 master birds per pen, and
received daily 90, 80, 70, 60, or 50% of its master feed intake. MEm
and growth were estimated by a non-linear mixed model explaining
ME intake (MEI) as a function of metabolic BW and gain. The RFI was
the random error term of the model. MEm were significantly different
between birds fed the low and high ME diets (127 and 140 kcal/kg0.57,
respectively; P < 0.001). There was a linear relationship between MEm
and MEI (P < 0.001). As feed intake increased, MEm was increased by
0.20 kcal0.57/kcal consumed. Hence, 20% of additional ME consumed
was lost as heat. The high ME diet increased MEm by 8.41 kcal/kg0.57.
There was also a linear relationship between RFI and MEI (P < 0.001).
For every kcal increase in MEI, RFI increased by 0.09 kcal. The high
ME diet increased RFI by 4.20 kcal. Thus, we conclude that lower
dietary ME level and ME intake both reduced DIT and decreased RFI.
Key Words: precision feeding, energy, maintenance, residual feed
intake, requirements
53 The rate and extent of starch digestion affects digestive
tract morphology and ileal brake activation in broiler chickens. Eugenia Herwig*, Rachel Savary, Karen Schwean-Lardner,
and Henry L. Classen, University of Saskatchewan, Saskatoon, SK,
Canada.
Slowly digested starch (SDS) positively affects broiler performance,
but little is known of the mechanisms involved. It was hypothesized
activation of the ileal brake by the presence of starch in the distal small
intestine increases digesta retention time and nutrient digestibility. Two
semi-purified starch sources with differing in vitro digestibility (wheat,
rapidly digested starch, RDS; pea, SDS) were used in 6 diets with differing RDS/SDS ratios: 100/0, 80/20, 60/40, 40/60, 20/80 and 0/100.
The diets were fed to male Ross 308 broilers housed in litter floor pens
from 0 to 28 d. At 14 and 28 d, digestive tract (full and empty weights,
length) and digesta pH measurements were recorded. Serum samples
were taken at 28 d to measure chicken Peptide YY (PYY), as an indicator
of ileal brake activation. Data were analyzed with regression analysis
using SAS 9.4, with P < 0.05 considered significant. At 14 d, relative
empty weights of the proventriculus, ileum and ceca increased linearly
with SDS level, whereas jejunum weight changed quadratically with a
maximum at 80% SDS birds. Besides the ileum, the relative contents of
the gizzard, duodenum, jejunum and ceca increased linearly with SDS
inclusion, while crop and ileal contents increased quadratically. At 28 d,
the relative weight of the digestive tract segments increased with SDS
level, except for the gizzard and duodenum, along with the crop, jejunum
and ileum contents. Only the relative ileum length increased with SDS
at 14 d, while the relative length of the small intestine increased with
SDS at 28 d. Cecal pH decreased linearly with SDS level at 14 d, but
not 28 d. Crop pH at 28 d showed a quadratic response to SDS level,
with the lowest pH for the 60% SDS diet. There were no significant
differences in PYY concentration. In conclusion, changes in digestive
tract size and content suggest ileal brake activation in broiler chickens
fed SDS, but this was not confirmed by serum PYY level.
Key Words: slowly digested starch, rapidly digested starch, digestive
tract morphology, ileal brake, broilers
18
54 Starch digestibility and apparent metabolizable energy
of western Canadian wheat market classes in broiler chickens.
Namalika D. Karunaratne*, Pierre Hucl, Ravindra N. Chibbar, Curtis
J. Pozniak, Dawn A. Abbott, and Henry L. Classen, University of
Saskatchewan, Saskatoon, SK, Canada.
Wheat is the primary grain fed to poultry in western Canada, but
its nutritional quality, including the nature of its starch digestibility,
may be affected by wheat market class. The objectives of this study
were to determine the rate and extent of starch digestibility of wheat
market classes in broiler chickens, and to determine the relationship
between starch digestibility and wheat AMEn. In vitro starch digestion
was assessed using gastric and small intestinal phases mimicking the
chicken digestive tract, while in vivo evaluation used 468 d-old male
broiler chickens randomly assigned to dietary treatments (6 cages/
treatment, 6 birds/cage) from 0 to 21 d of age. The study evaluated 2
wheat cultivars from each of 6 western Canadian wheat classes: Canadian Prairie Spring (CPS), Canadian Western Amber Durum (CWAD),
CW Hard White Spring (CWHWS), CW Red Spring (CWRS), CW
Soft White Spring (CWSWS), and General Purpose (GP). Data were
analyzed as a randomized complete block design and cultivars were
nested within market class. Pearson correlation was used to determine
correlations. Significance level was P ≤ 0.05. The starch digestibility
range and wheat class rankings were: proximal jejunum: 23.7 to 50.6%
(CWHWSc, CPSbc, CWSWSbc, CWRSab, GPa, CWADa); distal jejunum:
63.5 to 76.4% (CWHWSc, CPSbc, CWSWSbc, CWRSab, GPa, CWADa);
proximal ileum: 88.7 to 96.9% (CWSWSc, CPSbc, CWHWSbc, CWRSb,
GPb, CWADa); distal ileum: 94.4 to 98.5% (CWSWSb, CWHWSb,
CPSb, CWRSab, GPab, CWADa); excreta: 98.4 to 99.3% (CPSb, CWRSb,
CWHWSb, CWSWSab, GPab, CWADa). Wheat class affected wheat
AMEn with levels ranging from 3,203 to 3,411 kcal/kg at 90% DM
(CWRSc, CWSWSc, CPSb, GPb, CWADa, CWHWSa). Significant, but
low positive correlations were observed between in vitro and in vivo
starch digestibility, but no correlations were found between AMEn and
starch digestibility. In conclusion, rate and extent of starch digestibility
and AMEn were affected by western Canadian wheat class, but starch
digestibility did not predict AMEn.
Key Words: energy retention, slowly digestible starch, rapidly
digestible starch
55 Profile of synthesized versus preformed n-3 fatty acids in
chicken egg, liver and adipose tissue and the expression of genes
associated with hepatic lipid metabolism. Neijat Mohamad*, Peter
Eck, and James D. House, University of Manitoba, Winnipeg, MB,
Canada.
Dietary sources of omega-3 polyunsaturated fatty acids (n-3 PUFA),
including α-linolenic acid (ALA) and preformed long-chain PUFA
(LCPUFA, primarily docosahexaenoic acid, DHA), differ in their egg
LCPUFA enrichment efficiency. However, mechanisms leading to these
differences are unclear. To this end, the amount and distribution of n-3
PUFA in different lipid classes, including triacylglycerol (TAG) and total
phospholipid (PL) in yolk, liver and adipose, as well as the expression
of key hepatic enzymes in lipid metabolism were evaluated in laying
hens in response to changes in dietary supply. Seventy Lohmann LSLclassic hens (n = 10/treatment) consumed either a control diet containing
0.03% total n-3 PUFA, or the control supplemented with 0.36, 0.77, and
1.19 g/100 g feed of flaxseed oil or 1.00, 2.18, and 3.36 g/100 g feed of
DHA-Gold from either flaxseed oil or DHA-Gold, as sources of ALA
(precursor) or DHA (preformed), respectively; each corresponding
Poult. Sci. 95(E-Suppl. 1)
level supplying 0.20, 0.40, and 0.60% total n-3 PUFA. The study was
arranged in a completely randomized design, and data were analyzed
using the Proc Mixed procedure of SAS. ALA accumulated in a dosedependent manner (P < 0.0001) in total and lipid classes of yolk, liver,
and adipose (TAG only) for ALA- and DHA-fed hens. Unlike flaxseed
oil, preformed DHA contributed to greater (P < 0.0001) accumulation
of LCPUFA in total PL and TAG pool of yolk, and adipose TAG. This
may have been due to the elevated (P < 0.0001) expression of fatty
acid activation gene, acyl-CoA synthetase (ACSL1). There was no
difference in the level of eicosapentaenoic acid (EPA) incorporated in
the liver total lipids between the flaxseed oil or DHA-Gold treatments;
EPAliver = 2.1493x – 0.0064; R2 = 0.70, P < 0.0001 (combined data).
The latter result may indicate that the levels of EPA in the liver could
be involved in the regulation of LCPUFA metabolism in laying hens.
Key Words: egg yolk and tissues, fatty acid profile, flaxseed oil,
DHA-Gold, gene expression
56 Dietary n-3 fatty acids did not attenuate performance
during sustained inflammation on commercial broilers. Julianna
Jespersen*1, Isa Ehr1, Cheryl Morris1, Brian Kerr2, Anna Johnson1,
Nicholas Gabler1, and Elizabeth Bobeck1, 1Iowa State University,
Ames, IA, 2USDA-ARS, Ames, IA.
Dietary n-3 fatty acids (omega-3) have been shown to attenuate inflammatory processes and improve health. Therefore, utilizing a lipopolysaccharide (LPS) challenge model, our objective was to assess the
beneficial effects of dietary n-3 flaxseed and fish oils on broiler performance. Commercial broilers were fed either (1) a basal control diet (no
supplemented n-3); (2) basal diet + flaxseed oil (4% total n-3 consisting
of α-linolenic acid); or 3) basal diet + fish oil (4% total n-3 consisting
of eicosapentaenoic acid and docosahexaenoic acid) for a 4-wk (6–34
d of age) enrichment period followed by a 8-d LPS challenge (3 × 2
factorial). The LPS challenge was administered by injections of either
LPS (Escherichia coli 0111:B4) or sterile saline administered 4 times in
total (1 mg/kg BW every 48 h, with 20% increasing dosage from 35 to
42 d of age). Treatments were assigned in a randomized complete block
design with pen as the experimental unit (2 male Ross broilers/pen) with
10 replicates. All broilers were offered feed and water ad libitum. Broiler
body weight (BW) and feed intake (FI), feed conversion ratio (FCR), and
average daily gain (ADG) over the 8 d LPS challenge was analyzed for
the interaction (diet × LPS) or the main effects (diet and LPS). Means
were then separated using Tukey’s test (P ≤ 0.05). Body weight was
different at the start of the challenge (P < 0.01); therefore, it was used
as a covariate. No interactions were observed (P > 0.05). There was no
Diet effect on any measures (P ≥ 0.15). Saline broilers had heavier BW
(P < 0.01) and greater FI (P < 0.01) than the LPS-challenged broilers.
Poult. Sci. 95(E-Suppl. 1)
Additionally, ADG was reduced (P < 0.01) in LPS challenged broilers,
resulting in poorer FCR (P < 0.01) compared with the saline broilers.
In conclusion, flax and fish oil did not attenuate LPS-induced changes
in broiler performance. However, repeated challenges with LPS over
an 8-d period reduced broiler growth and feed intake, and attenuated
feed efficiency compared with the saline control broilers.
Key Words: broiler chicken, lipopolysaccharide, n-3 fatty acid,
inflammation
57 Effect of fat application site and percentage fines on feed
manufacturing characteristics, broiler live performance, and carcass parts yield. .Jeffrey T. Pope*, Adam C. Fahrenholz, and John T.
Brake, Prestage Department of Poultry Science, North Carolina State
University, Raleigh, NC.
The effects of 2 fat application sites and 2 percentage fines when fed from
16 to 44 d of age on feed manufacturing, broiler live performance, and
broiler carcass yield were studied. The effect of pellet quality entering a
post-pellet liquid application (PPLA) system was also studied. Each bird
was fed 908 g of a common crumbled broiler starter before transitioning onto one of 5 dietary treatments. The experiment was a randomized
complete block 2 × 2 design with one additional treatment to study the
effect of pellet quality entering a PPLA system. The fat application sites
used were in the mixer (MAF) and PPLA. The percentage added fines
used were 0 and 30%. Fines were initially separated by screening the
pelleted feed. Thus, there were initially 4 treatments MAF-0, MAF-30,
PPLA-0, and PPLA-30. With the PPLA-30 treatment, 2 mixing methods
were used to generate a fifth treatment. One PPLA-30 treatment had
fat added to a mixture of pellets and fines and the fifth treatment had
fat partitioned to the pellets and fines separately before recombining
to make the complete diet. The dietary treatments were assigned to 40
mixed-sex pens of 8 males plus 8 females resulting in 8 replicate pens
per treatment. BW and feed consumption were determined at 14, 28,
35, and 42 d of age and feed conversion ratio (FCR) was calculated on
the respective days. At 44 d, 2 males and 2 females that represented the
house average BW were selected from each pen for carcass yield and
weights of gizzard and proventriculus. PPLA fines had significantly
more energy and crude fat than PPLA pellets (P0.05). Females consuming PPLA-30 diets were significantly heavier than females consuming
MAF-30% diets (P0.05). We concluded that fat laden fines improved
performance of the birds coming to the feeder after many of the pellets
had been consumed.
Key Words: fat application site, pellet quality, percentage fines, feed
manufacturing
19