dr. nick gabler - evaluation of antibiotic alternatives for nursery pigs
TRANSCRIPT
Department of Animal Science
Evaluation of (Growth Promoting) Antibiotic
Alternatives for Nursery Pigs
Nicholas Gabler, Ph.D.Iowa Pork Congress
January 26, 2017
Department of Animal Science
Introduction• Antibiotics have been used in animal feed for
about 50 years • Anti-microbial agent• Growth-promoting agent and improvement in
performance
• Chlortetracycline, procaine penicillin, oxytetracycline, tylosin, bacitracin, neomycin sulfate, streptomycin, erythromycin, linomycin, oleandomycin, virginamycin, and bambermycins have been common feed additives for livestock and poultry
Department of Animal Science
FDA approved antibiotic use1. Disease treatment
2. Disease control
3. Disease prevention
• Therapeutic use for treating clinically sick animals, preventing or reducing the incidence of infectious disease agents
Department of Animal Science
Kent Schwartz (2016)
Department of Animal Science
FDA disapproved antibiotic use (2017)• FDA medically important antibiotics
• Same, or in same classes, as antibiotics used to treat humans
• Possible exceptions• Bacitracin• Mecadox?• Narasin• Bambermycin• Tiamulin
• Growth Promotion or Improvement of Nutritional Efficiency
• Increasing feed efficiency
• Improving growth rates
• Antibiotic growth promoters (AGPs)
• Administered at a low, sub-therapeutic dose
Department of Animal Science
Guidance for Industry #209• “Production uses” (growth promotion and
nutritional efficiency) of antibiotics in classes used in human medicine are injudicious
• Requires the use of these classes of antibiotics be under “veterinary oversight”• “Judicious use”
Department of Animal Science
AGPs• All swine antibiotics are affected under
Guidance #209
• Exceptions for AGPs for in feed and water use• Bacitracin• Carbadox• Bambermycin• Ionophores • Tiamulin
Department of Animal Science
Potential implications of antimicrobials on animal physiology
• Optimal animal health depends on host and microbial attributes
• AGPs have1) Indirect effects through
the microbiota
2) Direct effects on the host
• The functional and interactive effects of AGPs on the host and the microbiota are less clear
International Journal of Antimicrobial Agents, Volume 49, Issue 1, 2017, 12–24http://dx.doi.org/10.1016/j.ijantimicag.2016.08.006
Department of Animal ScienceInternational Journal of Antimicrobial Agents, Volume 49, Issue 1, 2017, 12–24http://dx.doi.org/10.1016/j.ijantimicag.2016.08.006
AGPs function:B. AGPs may function by
altering the composition of the microbiota to reduce competition for nutrients and/or by reducing pathogen load (bacteria-centric hypothesis)
C. Direct immunomodulatory agents that allow for resources to be shifted to metabolic functions (i.e. host-centric hypotheses)
The intestinal mucosa is a dynamic surface central both to metabolic and immune homeostasis
Department of Animal Science
FEED GRADE AGP ALTERNATIVES STUDY
(PRELIMINARY DATA- ISU/USDA NADC)
M. Schroyen, J. Trachsel, S. Curry, H. Allen, C. Tuggle, C. Loving, E. Burrough, N. Gabler
Department of Animal Science
Post-weaned performance (5 weeks) Diet ADG, kg ADFI, kg G:F Control 0.32a 0.37a 0.88 CTC 0.43b 0.51b 0.85 5% inulin 0.37ab 0.44ab 0.87 5% Resistant Starch (RS) 0.40b 0.46ab 0.87 0.25% Butyrate 0.36ab 0.42ab 0.88
0 1 2 3 4 5 6-1
1
3
5
7
9
11
13
15Control
CTC
5% inulin
5% RS
0.25% Butyrate
Week
Delta
BW
, kg
Department of Animal Science
Cecal SCFA
Department of Animal Science
DEVELOPMENT AND VALIDATION OF A STANDARDIZED
SCIENTIFIC PROTOCOL EVALUATING ANTIBIOTIC
ALTERNATIVES IN GROWING PIGS
(NPB# 15-204)
Department of Animal Science
Project Team• Iowa State University
• Nicholas Gabler (AnS)• John Patience (AnS)• Kent Schwartz (VDL)• Chris Rademacher
(VDPAM)• Alex Ramierez (VDPAM)• Daniel Linhares (VDPAM)
• Wes Schweer (AnS)• Kristin Olsen (AnS)
• USDA-NADC• Heather Allen• Crystal Loving
Department of Animal Science
Project Objectives• To develop a framework within which studies on alternatives
to antibiotic growth promotants may be conducted
1. To develop a protocol that defines the critical and essential components that can be used to undertake studies on alternatives of antibiotic growth promoters, such that results will be clear and definitive and can be compared to other studies on the same topics.
• This protocol will have sufficient detail to achieve this objective but also have sufficient flexibility and framework to apply to a broad range of experimental approaches and topics
2. To validate the protocol(s) defined by objective 1 by undertaking a study in nursery pigs to provide data on options for AGP replacement in nursery diets
Department of Animal Science
Proposed outcomes for the NPB• An extensive review of nursery-finisher studies, including
methodologies and designs that will be utilized to construct a standardized experimental protocol that identifies the essential requirements of an effective evaluation of alternatives to AGPs
• The results of a validation study to test the adequacy and efficacy of the proposed standardized protocol
• Data on different approaches to replacing AGPs – i.e. organic acids, pre- or pro-biotics and specific diet formulations.
• The validation phase will not only confirm the validity of the standard protocol but it will also provide useful data on the topic of interest
Department of Animal Science
Search term into database
Remove duplicates, keep only journal articles since 1990
Exclude articles that didn’t contain performance data or mortality in abstract
Keep articles in English with full text available
Department of Animal Science
Search Parameters• Databases used:
• Pubmed• Sciencedirect• Web of Science• CAB Abstracts• Agricola
• Searched all years for initial search
Department of Animal Science
Search ParametersCategory Search TermProbiotic probiotic AND swine(pig)Prebiotic prebiotic AND swineOligosaccharide
oligosaccharide AND swine AND wean
Organic Acids (“organic acid”) OR (“organic acids”) AND swine
Essential oils / botanicals / plant extracts
essential oil AND swinebotanical AND swineplant extract AND swine AND wean
Yeast yeast AND swine AND weanResistant starch/ fiber
starch AND swine AND weanfiber AND swine AND wean
Zinc/Copper zinc AND swine AND weancopper AND swine AND wean
Lysozyme lysozyme AND swine
Department of Animal Science
Search Parameters• Export all references to Endnote
• Exclude papers previous to 1990• Exclude duplicates and keep only research articles
• Read abstracts and keep only articles that report performance data or mortality
• Obtained full text papers written in English
Department of Animal Science
Criteria by which each paper was evaluated
• Challenge (yes/no)• n/trt• Exp. Unit• Pigs/pen• Age of pig (days)• Start BW (kg)• Genetics• Duration of feeding
(days)
• Diet components• ADG (-,0,+)• ADFI (-,0,+)• Feed Efficiency
(-,0,+)• Mortality (-,0,+)• Blood Assay (yes/no)• Tissue Assay (yes/no)• Microbiome (yes/no)
Department of Animal Science
Paper Criteria• If paper included control and multiple
treatments, each treatment considered one experiment
• Example:• Trts: control, butyric acid, propionic acid,
butyric + propionic acid• Paper would include 3 “experiments”
Department of Animal Science
Probiotics• Search term: probiotic AND swine• Total articles: 2,296• After duplicates + since 1990: 1,629• Contain performance/mortality: 288• Articles available: 172• Probiotic type: Bacillus (39), Bifidobacterium
(26), Enterococcus (27), Escherichia (8), Lactobacillus (62), Lactococcus (5), Pediococcus (10), Saccharomyces (12), combo (65), other (5)
Department of Animal Science
Probiotics• 309 total studies• 46 challenge studies• ADG: (+) = 172; 0 = 172; (-) = 5; not reported = 10• ADFI: (+) = 40; 0 = 153; (-) = 10; not reported = 106• GF: (+) = 78; 0 = 134; (-) = 3; not reported = 94• Mortality: (+) = 15; 0 = 28; (-) = 0; not reported =
266• Avg. n/trt: 21.1• Avg. pigs/pen: 6.0• Avg. study duration: 35.9 days• Avg. age: 23.9 days• Avg. BW: 14.2 kg
Department of Animal Science
Probiotic - ADGRespons
e#
studies
Start BW (kg)
Duration
(days)Age
(days)
(0) 172 15.1 29.6 23.9(-) 5 25.7 28.0 44.2(+) 122 12.9 45.7 23.5nr 10 5.0 26.2 17.3
Total 309
Response n/trt Pig/pen
Avg Min
Max
Med
Stdev
Avg Min
Max
Med
Stdev
(0) 14.6 2 400 8.0 32.5 4.9 1 22 4.0 4.2(-) 14.0 12 16 15.
01.7 5.8 1 14 4.0 4.9
(+) 18.5 2 600 6.0 58.4 7.3 1 35 6.0 5.6nr 165.
52 147
110.0
436.2 8.4 1 11 10.5 4.0
No change in growth
Negative impact on growth
Positive impact on growth
Not reported
Department of Animal Science
Probiotics - Observations• No genetic pattern – 44 genetic
combinations• Of 122 (ADG+):
• 37 probiotic combination• 29 Lactobacillus spp.
• 8/29 = Lactobacillus plantarum• 20 Bacillus spp.• 16 Enterococcus spp.
• 15/16 = Enterococcus faecium
Department of Animal Science
Prebiotics• Search term: prebiotic AND swine• Total articles: 517• After duplicates + since 1990: 440• Contain performance/mortality: 53• Articles available: 39
Department of Animal Science
Prebiotics• 92 total studies• 7 challenge studies• ADG: (+) = 10; 0 = 80; (-) = 0; not reported = 2• ADFI: (+) = 4; 0 = 74; (-) = 1; not reported = 14• GF: (+) = 10; 0 = 60; (-) = 0; not reported = 23• Mortality: (+) = 0; 0 = 3; (-) = 0; not reported = 90• Avg. n/trt: 10.4• Avg. pigs/pen: 3.9• Avg. study duration: 28.8 days• Avg. age: 25.0 days• Avg. BW: 9.9 kg
Department of Animal Science
Prebiotic - ADG
Response
# studie
s
Start BW (kg)
Duration (days)
Age (days)
(0) 86 9.0 26.0 23.8(-) 0 -- -- --(+) 11 10.9 45.8 21.3nr 2 9.8 19.0 25.0
Total 99
Response n/trt Pig/pen
Avg Min
Max
Med
Stdev
Avg Min
Max
Med
Stdev
(0) 11 2 71 10.0
8.5 3.8 1 11 4.0 2.4
(-) -- -- -- -- -- -- -- -- -- --(+) 6.8 4 8 7 1.3 4.6 3 10 4.0 2.1nr 6 6 6 6.0 0.0 1.0 1 1 1.0 0.0
Department of Animal Science
Prebiotic – Observations • No genetic pattern – 7 genetic combinations• Diets – 5/11 Corn-soy based• Of 11 (ADG+):
• 3/10 = sorbitol• 3/10 = lactulose
Department of Animal Science
Oligosaccharide• Search term: oligosaccharide AND swine
AND wean• Total articles: 485• After duplicates + since 1990: 376• Contain performance/mortality: 74• Articles available: 44
Department of Animal Science
Oligosaccharide• 92 total studies• 5 challenge studies• ADG: (+) = 17; 0 = 71; (-) = 4; not reported = 0• ADFI: (+) = 6; 0 = 58; (-) = 3; not reported = 3• GF: (+) = 17; 0 = 48; (-) = 0; not reported = 5• Mortality: (+) = 1; 0 = 5; (-) = 0; not reported = 64• Avg. n/trt: 10.3• Avg. pigs/pen: 5.9• Avg. study duration: 30.6 days• Avg. age: 22.9 days• Avg. BW: 7.5 kg
Department of Animal Science
Oligosaccharide - ADGRespons
e#
studies
Start BW (kg)
Duration (days)
Age (days)
(0) 71 5.3 30.4 25.0(-) 4 2.1 22.8 24.8(+) 17 3.6 24.0 18.6nr 0 -- -- --
Total 92
Response n/trt Pig/pen
Avg Min
Max
Med
Stdev
Avg Min
Max
Med
Stdev
(0) 10.7 3.0 50.0 6.0 11.7 6.0 1.0 32.0 5.0 5.3(-) 7.3 6.0 10.0 6.5 1.6 4.5 1.0 6.0 5.5 2.1(+) 13.4 3.0 50.0 8.0 12.9 7.4 1.0 12.0 10.0 3.6nr -- -- -- -- -- -- -- -- -- --
Department of Animal Science
Oligosaccharide – Observations• No genetic pattern – 8 genetic combinations• Diet – 7/17 Corn-soy based
Department of Animal Science
Organic Acids• Search term: (“organic acid”) OR (“organic
acids”)) AND swine• Total articles: 1,963• After duplicates + since 1990: 1,573• Contain performance/mortality: 130• Articles available: 80
Department of Animal Science
Organic Acids• 154 total studies• 8 challenge studies• ADG: (+) = 44; 0 = 84; (-) = 2; not reported = 0• ADFI: (+) = 17; 0 = 107; (-) = 1; not reported = 5• GF: (+) = 26; 0 = 101; (-) = 0; not reported = 3• Mortality: (+) = 10; 0 = 5; (-) = 0; not reported =
115• Avg. n/trt: 8.5• Avg. pigs/pen: 6.3 • Avg. study duration: 43.8 days• Avg. age: 24.3 days• Avg. BW: 13.0 kg
Department of Animal Science
Organic Acids - ADGRespons
e#
studies
Start BW (kg)
Duration (days)
Age (days)
(0) 104 13.5 43.5 24.3(-) 2 8.1 31.5 25.5(+) 48 14.9 45.6 27.1nr -- -- -- --
Total 154
Response n/trt Pig/pen
Avg
Min
Max
Med
Stdev
Avg Min
Max
Med
Stdev
(0) 10.3
2 168 7.0 18.1 5.9 1 34 4.0 6.1
(-) 7.5 5 10 7.5 2.5 4.0 2 6 4.0 2.0(+) 7.8 3 40 6.0 6.7 7.5 1 20 6.0 5.0nr -- -- -- -- -- -- -- -- -- --
Department of Animal Science
Organic Acids – Observations• No genetic pattern – 24 genetic
combinations• Diet – 26/48 Corn-soy based
Department of Animal Science
Essential oils/botanicals/plant extracts• Search term: plant extract AND swine AND
wean• Search term: botanical AND swine AND wean• Search term: essential oil AND swine• Total articles: 2,608• After duplicates + since 1990: 1,663• Contain performance/mortality: 181• Articles available: 131
Department of Animal Science
Essential oils/botanicals/plant extracts• 334 total studies• 40 challenge studies• ADG: (+) = 74; 0 = 243; (-) = 8; not reported = 9• ADFI: (+) = 34; 0 = 283; (-) = 14; not reported = 44• GF: (+) = 55; 0 = 221; (-) = 6; not reported = 48• Mortality: (+) = 1; 0 = 15; (-) = 1; not reported =
313• Avg. n/trt: 8.4• Avg. pigs/pen: 5.1• Avg. study duration: 32.8 days• Avg. age: 25.6 days• Avg. BW: 11.2 kg
Department of Animal Science
Ess. Oils/Botanicals - ADGRespons
e#
studies
Start BW (kg)
Duration (days)
Age (days)
(0) 243 10.3 32.3 24.1(-) 8 22.5 44.6 22.0(+) 74 11.6 35.6 25.0nr 9 25.2 11.3 66.6
Total 334
Response n/trt Pig/pen
Avg
Min
Max
Med
Stdev
Avg Min
Max
Med
Stdev
(0) 8.1 1 50 6.0 5.6 4.9 1 34 4.0 4.2(-) 13.
85 32 10.
08.8 5.6 1 9 5.5 3.1
(+) 8.3 2 33 6.0 5.4 5.6 1 30 4.0 4.3nr 11.
44 15 12.
02.8 3.6 1 24 1.0 7.2
Department of Animal Science
Ess. Oils/Botanicals - Observations• No genetic pattern – 24 genetic
combinations• Diet – 35/74 Corn-soy based
Department of Animal Science
Yeast• Search term: yeast AND swine AND wean• Total articles: 782• After duplicates + since 1990: 426• Contain performance/mortality: 96• Articles available: 60
Department of Animal Science
Yeast• 87 total studies• 12 challenge studies• ADG: (+) = 22; 0 = 63; (-) = 1; not reported = 1• ADFI: (+) = 12; 0 = 57; (-) = 1; not reported = 17• GF: (+) = 10; 0 = 54; (-) = 1; not reported = 22• Mortality: (+) = 1; 0 = 7; (-) = 0; not reported = 79• Avg. n/trt: 12.0• Avg. pigs/pen: 4.9• Avg. study duration: 25.6 days• Avg. age: 21.2 days• Avg. BW: 8.4 kg
Department of Animal Science
Yeast - ADGRespons
e#
studies
Start BW (kg)
Duration (days)
Age (days)
(0) 63 9.2 22.9 21.6(-) 1 6.6 28.0 22.0(+) 22 6.3 31.0 19.1nr 1 -- 1.0 35.0
Total 87
Response n/trt Pig/pen
Avg Min
Max
Med
Stdev
Avg Min
Max
Med
Stdev
(0) 10.5 2 64 8.0 8.9 4.6 1 16 4.0 3.7(-) 7.0 7 7 7.0 0.0 5.0 5 5 5.0 0.0(+) 16.3 4 163 8.0 32.4 5.9 1 20 4.0 4.5nr 15.0 15 15 15.
00.0 1.0 1 1 1.0 0.0
Department of Animal Science
Yeast - Observations• No genetic pattern – 16 genetic
combinations• Diet – 15/22 Corn-soy based
Department of Animal Science
Resistant starch/fiber• Search term: starch AND swine AND wean• Search term: fiber AND swine AND wean• Total articles: 2,432• After duplicates + since 1990: 1,352• Contain performance/mortality: 157• Articles available: 81
Department of Animal Science
Resistant starch/fiber• 203 total studies• 10 challenge studies• ADG: (+) = 19; 0 = 148; (-) = 34; not reported = 2• ADFI: (+) = 12; 0 = 148; (-) = 28; not reported = 15• GF: (+) = 14; 0 = 137; (-) = 18; not reported = 34• Mortality: (+) = 2; 0 = 11; (-) = 5; not reported =
185• Avg. n/trt: 10.8• Avg. pigs/pen: 3.6• Avg. study duration: 32.1 days• Avg. age: 25.3 days• Avg. BW: 9.7 kg
Department of Animal Science
Starch/Fiber - ADGRespons
e#
studies
Start BW (kg)
Duration (days)
Age (days)
(0) 148 9.8 32.7 24.5(-) 34 10.4 33.0 29.4(+) 19 8.0 26.7 23.2nr 2 9.8 24.0 40.0
Total 203
Response n/trt Pig/pen
Avg
Min
Max
Med
Stdev
Avg Min
Max
Med
Stdev
(0) 9.6 2 100 8.0 11.6 3.1 1 14 2.0 2.4(-) 6.6 3 20 5.0 4.1 2.5 1 8 2.0 1.9(+) 27.
52 353 11.
076.9 9.6 1 37 4.0 12.1
nr 6.0 6 6 6.0 0.0 1.0 1 1 1.0 0.0
Department of Animal Science
Starch/Fiber - Observations• No genetic pattern – 12 genetic
combinations• Diet – no pattern
Department of Animal Science
Zinc/Copper• Search term: zinc AND swine AND wean• Search term: copper AND swine AND wean• Total articles: 1,953• After duplicates + since 1990: 797• Contain performance/mortality: 167• Articles available: 123
Department of Animal Science
Zinc/Copper• 495 total studies:• 38 challenge studies• ADG: (+) = 211; 0 = 278; (-) = 3; not reported = 3• ADFI: (+) = 129; 0 = 342; (-) = 5; not reported = 19• GF: (+) = 100; 0 = 348; (-) = 3; not reported = 44• Mortality: (+) = 9; 0 = 8; (-) = 0; not reported = 478• Avg. n/trt: 11.7• Avg. pigs/pen: 5.1• Avg. study duration: 30.2 days• Avg. age: 24.5 days• Avg. BW: 7.6 kg
Department of Animal Science
Zn/Cu - ADGRespons
e#
studies
Start BW (kg)
Duration (days)
Age (days)
(0) 278 7.9 28.7 25.2(-) 3 2.6 20.0 12.7(+) 211 7.2 32.6 23.7nr 3 6.9 13.7 20.0
Total 495
Response n/trt Pig/pen
Avg
Min
Max
Med
Stdev
Avg Min
Max
Med
Stdev
(0) 12.7
1 137 6.0 21.1 4.4 1 28 4.0 3.3
(-) 6.0 2 10 6.0 3.3 8.5 4 13 8.5 4.5(+) 10.
61 123 6.0 18.0 6.1 1 21 5.0 4.3
nr 8.0 8 8 8.0 0.0 3.0 1 7 1.0 2.8
Department of Animal Science
Zn/Cu - Observations• No genetic pattern – 47 genetic
combinations• Diet – 140/211 Corn-soy based• Of 211 (+):
• 142 Zn• 24/142 = 3000 ppm• 16/142 = 2500 ppm
• 55 Cu• 11/55 = 250 ppm• 10/55 = 200 ppm
Department of Animal Science
Lysozyme• This enzyme functions by attacking
peptidoglycans found in the cell walls of bacteria
• Especially Gram-positive bacteria
• Search term: lysozyme AND swine• Total articles: 1,618• After duplicates + since 1990: 867• Contain performance/mortality: 16• Articles available: 9
Department of Animal Science
Lysozyme• 9 total studies• 3 challenge studies• ADG: (+) = 4; 0 = 3; (-) = 1; not reported = 1• ADFI: (+) = 1; 0 = 5; (-) = 0; not reported = 3• GF: (+) = 3; 0 = 3; (-) = 1; not reported = 2• Mortality: (+) = 0; 0 = 0; (-) = 0; not reported = 9• Avg. n/trt: 11.0• Avg. pigs/pen: 6.0• Avg. study duration: 22.9 days• Avg. age: 15.0 days• Avg. BW: 6.4 kg
Department of Animal Science
Lysozyme - ADGRespons
e#
studies
Start BW (kg)
Duration (days)
Age (days)
(0) 3 4.9 25.7 9.7(-) 1 5.8 21.0 17.0(+) 4 6.9 24.5 21.3nr 1 -- 10.0 4.0
Total 9
Response n/trt Pig/pen
Avg
Min
Max
Med
Stdev
Avg
Min
Max
Med
Stdev
(0) 11.7
6 20 9.0 6.0 2.3 1 5 1.0 1.9
(-) 5.0 5 5 5.0 0.0 4.0 4 4 4.0 0.0(+) 13.
35 16 16.
04.8 10.
54 25 6.5 8.5
nr 6.0 6 6 6.0 0.0 1.0 1 1 1.0 0.0
Department of Animal Science
Lysozyme - Observations• No genetic pattern – 7 genetic combinations• Diet –
• 4/9 Corn-soy based • 3/9 milk/milk replacer
Department of Animal Science
Combined Overall Data - ADG
Response # studies Av. Start BW (kg)
Av. Duration (days)
Av. Age (days)
0 1119 10.1 30.7 24.1(-) 57 12.2 32.6 28.7(+) 498 (29%) 9.7 36.2 23.5nr 24 17.1 16.4 36.9
Total 1698
Response n/trt Pig/pen
Avg
Min
Max Med
Stdev
Avg
Min
Max
Med
Stdev
(0) 11.0
1 400 7.0 18.1 4.5 1 34 4.0 4.0
(-) 8.2 2 32 6.0 5.5 3.5 1 13 4.0 2.7(+) 12.
81 600 6.0 35.7 6.5 1 37 5.0 5.3
nr 74.6
2 1471
11.0
291.9 3.4 1 24 1.0 5.6
Department of Animal Science
Prob
iotic
(n=26
7)
Preb
iotic
(n=92
)
Oligos
acch
aride
(n=81
)
Organ
ic Acid
(n=13
0)
Botan
icals
(n=33
4)
Yeas
t (n=
87)
Star
ch/Fi
ber (
n=20
3)
Zn/Cu
(n=49
5)
Lyso
zyme (
n=9)
Total
(n=16
98)
0102030405060708090
100
58
87 8165 73 72 73
5633
66
1.5
0.0 4.9
1.52.4 1.1
16.7
0.6
11.1
3.439
11 1434 22 25
9
4344
29
2.2 2.2 0.0 2.7 1.1 1.0 0.611.1 1.4
(0) (-) (+) nr
%, S
igni
fican
t ADG
resp
onse
Department of Animal Science
What’s next?• Utilizing pivot tables to identify trends, get
perspective of previous studies• Plan to make Excel file available to search
outcomes
• Identify “good” practices and “must” practices• May not be blanket practices, can vary
depending on product
• Conduct validation study
Department of Animal Science
Conclusions• Great judicious use of antibiotics
• AGP function is poorly understood• More complex than just shifting enteric
microbiota populations or alterations in intestinal integrity
• Could have direct and indirect functions• More comprehensive understanding needed• Testing (evaluation) protocols for AGP
alternatives are being developed to help find effective alternatives
Department of Animal Science
QUESTIONS?