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Nouri A. Age-dependent development trends (models) of intestinal significant microbiota species and Eimeria oocysts in coccidia-challenged broiler chickens as affected by dietary encapsulated organic acids and anticoccidial drugs. Avian Pathol 2024; 53:264-284. [PMID: 38349388 DOI: 10.1080/03079457.2024.2319284] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2023] [Accepted: 09/20/2023] [Indexed: 03/12/2024]
Abstract
ABSTRACTThe study was conducted to investigate the effect of dietary encapsulated organic acids (EOAs) and anticoccidials on the age-dependent development trend of intestinal Lactobacillus, E. coli, coliforms, and Eimeria in Eimeria spp.-infected broiler chickens from reused litter. In total, 525 mixed-sex 1-day-old broiler chickens were used in an uninfected/un-supplemented control plus a 2 (no EOA or 0.1% EOA) × 3 (no anticoccidial, 0.05% maduramicin, and 0.02% diclazuril) factorial arrangement of treatments as a completely randomized design with five replicates of 15 chickens. Results indicated that the cubic model is the best model for explaining the development trends of the intestinal microbial population in uninfected and infected chickens (affected by the EOAs and anticoccidials). Based on the cubic models, the microbial populations had development trends with a decreasing slope from 1-day-old until the early or middle finisher period. EOAs and anticoccidials, especially their simultaneous usage, improved (P < 0.05) the linear and cubic models' slope (affected negatively by Eimeria infection). A polynomial model (order = 6) was determined as the best model for explaining the EOAs and anticoccidial effects on the trend of intestinal Eimeria oocysts in infected chickens. The infection peak (which happened at 25 days) was reduced by EOAs and anticoccidials, especially their simultaneous usage. In conclusion, cubic and polynomial (order = 6) regressions are the best models fitted for explaining the microbiota and Eimeria oocysts trends, respectively. EOAs and anticoccidials, especially their simultaneous usage, had beneficial effects on the microbiota and Eimeria development trends and gastrointestinal health in coccidia-infected broiler chickens.RESEARCH HIGHLIGHTSCubic regression is the best model for explaining intestinal microbiota development.Polynomial regression is the best model for intestinal Eimeria oocysts development.Age-development trends are affected by dietary encapsulated organic acids and anticoccidials.
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Affiliation(s)
- Ali Nouri
- Department of Animal Science, Garmsar Branch, Islamic Azad University, Garmsar, Iran
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Bean-Hodgins L, Mohammadigheisar M, Edwards A, Wang C, Barbut S, Kiarie E. Comparative impact of conventional and alternative gut health management programs on growth performance and breast meat quality in broiler chickens raised in commercial and research settings. J APPL POULTRY RES 2022. [DOI: 10.1016/j.japr.2021.100228] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
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Bawm S, Chel HM, Khaing Y, Hmoon MM, Thein SS, Win SY, Soe NC, Thaw YN, Hayashi N, Win MM, Htun LL, Nonaka N, Katakura K, Nakao R. The strong influence of management factors on coccidian infections in smallholder pig farms and the first molecular identification of Cystoisospora suis in Myanmar. Parasite 2022; 29:1. [PMID: 35089127 PMCID: PMC8796702 DOI: 10.1051/parasite/2022006] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2021] [Accepted: 01/17/2022] [Indexed: 11/14/2022] Open
Abstract
A cross-sectional study was conducted to investigate coccidian infection and associated factors in smallholder pigs, and to identify Cystoisospora oocysts by PCR. A total of 500 pig faecal samples from 330 smallholder farms were collected in Nay Pyi Taw, Myanmar. The faecal flotation method was used to identify Eimeria and Cystoisospora species, and oocyst counts per gram (OPG) of faeces were recorded. Oocysts were differentiated after sporulation. Oocyst DNA was subjected to ITS1-targeted Cystoisospora-specific PCR. The overall coccidian oocyst detection rate by microscopic was 89.0% (445/500). Among the studied samples, 74.0% (370/500) and 70.6% (353/500), were found to be positive with Eimeria spp. and Cystoisospora suis oocysts, respectively. The sequences of C. suis detected were 100% identical to those of C. suis reported from Japan, and had 99.5% resemblance to sequences from Australia and China. Weaner pigs showed the significantly highest (p < 0.05) OPG when compared to other age groups. The highest intensity of coccidian infection (p < 0.05) was found in pigs fed local feed, pigs raised on earthen floors and pigs under poor hygienic conditions. Factors such as age, breed, feed type, and housing floors were found to be significantly associated with coccidian infection (p < 0.05). Age, as well as management factors including floor type, feed type, and hygiene practices on the farm, had a strong influence on the occurrence of coccidian infection in pigs. This is the first study in Myanmar on coccidian infection in pigs and molecular detection of C. suis.
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Affiliation(s)
- Saw Bawm
- Department of International Relations and Information Technology, Yezin, Nay Pyi Taw 15013, Myanmar - Department of Pharmacology and Parasitology, University of Veterinary Science, Yezin, Nay Pyi Taw 15013, Myanmar
| | - Hla Myet Chel
- Department of Pharmacology and Parasitology, University of Veterinary Science, Yezin, Nay Pyi Taw 15013, Myanmar
| | - Yadanar Khaing
- Department of International Relations and Information Technology, Yezin, Nay Pyi Taw 15013, Myanmar
| | - Myint Myint Hmoon
- Department of Pharmacology and Parasitology, University of Veterinary Science, Yezin, Nay Pyi Taw 15013, Myanmar
| | - Su Su Thein
- Department of Pharmacology and Parasitology, University of Veterinary Science, Yezin, Nay Pyi Taw 15013, Myanmar
| | - Shwe Yee Win
- Department of Pharmacology and Parasitology, University of Veterinary Science, Yezin, Nay Pyi Taw 15013, Myanmar
| | - Nyein Chan Soe
- Department of Pharmacology and Parasitology, University of Veterinary Science, Yezin, Nay Pyi Taw 15013, Myanmar
| | - Yu Nandi Thaw
- Department of Pharmacology and Parasitology, University of Veterinary Science, Yezin, Nay Pyi Taw 15013, Myanmar
| | - Naoki Hayashi
- Laboratory of Parasitology, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan
| | - Mar Mar Win
- Rector office, University of Veterinary Science, Yezin, Nay Pyi Taw 15013, Myanmar
| | - Lat Lat Htun
- Department of Pharmacology and Parasitology, University of Veterinary Science, Yezin, Nay Pyi Taw 15013, Myanmar
| | - Nariaki Nonaka
- Laboratory of Parasitology, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan
| | - Ken Katakura
- Laboratory of Parasitology, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan
| | - Ryo Nakao
- Laboratory of Parasitology, Graduate School of Infectious Diseases, Faculty of Veterinary Medicine, Hokkaido University, Sapporo 060-0818, Japan
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Taylor J, Walk C, Misiura M, Sorbara JOB, Giannenas I, Kyriazakis I. Quantifying the effect of coccidiosis on broiler performance and infection outcomes in the presence and absence of control methods. Poult Sci 2022; 101:101746. [PMID: 35219136 PMCID: PMC8881651 DOI: 10.1016/j.psj.2022.101746] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2021] [Revised: 01/13/2022] [Accepted: 01/13/2022] [Indexed: 01/31/2023] Open
Abstract
A systematic review and meta-analysis was conducted to investigate the role of Eimeria species, dose and inoculation time, on performance and infection outcomes of different broiler strains infected for different study durations. The meta-analysis addressed E. acervulina, E. maxima, E. tenella, and mixed species infections, and involved data from 72 peer-reviewed articles, corresponding to 521 treatments performed on 20,756 broilers. A secondary objective was to investigate the effects of synthetic anticoccidials, ionophores, and vaccination against Eimeria on the above outcomes. Performance during infection was scaled (%) to that of the uninfected birds. Infection reduced scaled ADFI and ADG (P < 0.001) and increased feed conversion ratio (FCR; P < 0.05); there was a significant interaction between dose and species on scaled ADFI and ADG, suggesting that different species affected these variables to different extents (P < 0.001). There was a tendency for an interaction between dose and broiler strain on scaled ADFI (P = 0.079), and a significant interaction between these variables on scaled ADG (P < 0.01). A tendency for an interaction between oocyst dose and Eimeria species (P = 0.067) on maximum number of oocysts excreted was observed. Lesion scores were significantly affected by dose, species, and their interaction (P < 0.05), the latter caused by an increase in the lesion scores during E. maxima and E. tenella infections. Control methods significantly affected scaled ADG and FCR (P < 0.05) and there was an interaction between dose and control methods on ADFI (P < 0.001). Synthetic anticoccidial use improved scaled ADG (P < 0.01), whereas ionophores improved FCR compared with untreated birds (P < 0.01). An interaction between dose and control method on scaled ADFI was caused by the higher ADFI of vaccinated compared to untreated birds, as dose increased. There was a significant effect of control methods on lesion scores (P < 0.01). All findings advance our understanding of the factors that influence the impact of coccidiosis and its controls in broilers.
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Affiliation(s)
- James Taylor
- Institute for Global Food Security, Queen's University, Belfast BT7 1NN, United Kingdom
| | - Carrie Walk
- DSM Nutritional Products, Kaiseraugst 4303, Switzerland
| | - Maciej Misiura
- Institute for Global Food Security, Queen's University, Belfast BT7 1NN, United Kingdom
| | | | - Ilias Giannenas
- Laboratory of Nutrition, School of Veterinary Medicine, Faculty of Health Sciences, Aristotle University of Thessaloniki, 54627 Thessaloniki, Greece
| | - Ilias Kyriazakis
- Institute for Global Food Security, Queen's University, Belfast BT7 1NN, United Kingdom.
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Gittins J, Wynn S, Parker D, Lister S. The economic and environmental impacts of removing ionophore coccidiostats from the UK broiler sector. WORLD POULTRY SCI J 2021. [DOI: 10.1080/00439339.2022.1988807] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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Bindari YR, Kheravii SK, Morton CL, Wu SB, Walkden-Brown SW, Gerber PF. Molecular detection of Eimeria species and Clostridium perfringens in poultry dust and pooled excreta of commercial broiler chicken flocks differing in productive performance. Vet Parasitol 2021; 291:109361. [PMID: 33550163 DOI: 10.1016/j.vetpar.2021.109361] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/26/2020] [Revised: 12/21/2020] [Accepted: 01/10/2021] [Indexed: 02/05/2023]
Abstract
Necrotic enteritis and coccidiosis are the most economically detrimental enteric diseases of broiler chickens. This study aimed to investigate the association of DNA load of Clostridium perfringens, netB, and five Eimeria species (E. brunetti, E. maxima, E. necatrix, E. acervulina and E. tenella) in poultry house dust and pooled excreta with flock productive performance. The dust and pooled excreta from the floor were collected weekly at days 7, 14, 21, 28 and 35 of chicken age from 16 flocks of eight farms from two Australian integrator companies. The farms were ranked as high or low performers by each integrator according to the production performance of studied flocks. Eimeria tenella and necatrix were not detected in any farm while E. brunetti was detected in a low-performance farm and netB was detected in a high-performance farm. C. perfringens, E. acervulina and E. maxima DNA were detected on all farms with no significant differences in DNA load between high and low-performance farms or companies. The lack of association of pathogen DNA load and farm performance is possibly due to overall low to moderate pathogen DNA load detected in this study. Further studies on a larger number of farms are needed to determine whether these population level measurements of key pathogens based on PCR detection of nucleic acids are correlated with performance variables.
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Affiliation(s)
- Yugal Raj Bindari
- Animal Science, School of Environmental and Rural Science, University of New England, Armidale, NSW, 2351, Australia
| | - Sarbast K Kheravii
- Animal Science, School of Environmental and Rural Science, University of New England, Armidale, NSW, 2351, Australia
| | - Christine L Morton
- Animal Science, School of Environmental and Rural Science, University of New England, Armidale, NSW, 2351, Australia
| | - Shu-Biao Wu
- Animal Science, School of Environmental and Rural Science, University of New England, Armidale, NSW, 2351, Australia
| | - Stephen W Walkden-Brown
- Animal Science, School of Environmental and Rural Science, University of New England, Armidale, NSW, 2351, Australia
| | - Priscilla F Gerber
- Animal Science, School of Environmental and Rural Science, University of New England, Armidale, NSW, 2351, Australia.
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Sokale AO, Williams CJ, Hoerr FJ, Collins KEC, Peebles ED. Effects of administration of an in ovo coccidiosis vaccine at different embryonic ages on vaccine cycling and performance of broiler chickens ,. Poult Sci 2020; 100:100914. [PMID: 33518328 PMCID: PMC7936202 DOI: 10.1016/j.psj.2020.11.078] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2020] [Revised: 11/11/2020] [Accepted: 11/23/2020] [Indexed: 11/29/2022] Open
Abstract
Use of a live coccidiosis vaccine has become an increasingly common method to control coccidiosis, especially in antibiotic-free broiler production. The Inovocox EM1 vaccine (EM1) is recommended for the vaccination of embryonated broiler hatching eggs between 18.0 and 19.0 d of incubation (doi). This allows for earlier acquisition of immunity to wild-type coccidia. However, it is unclear whether the difference in embryo age at the time of in ovo injection can influence the effect of the vaccine during grow-out as well as if the growth performance of broiler chickens is affected. Therefore, the objective of the study was to evaluate the effects of 2 injection ages (18.5 and 19.0 doi) and 3 injection types (noninjected, diluent, and vaccine) in a 3 × 2 factorial design, consisting of 10 replicates per treatment (60 treatment-replicate groups). There was a significant effect of injection age on BW at 0, 14, and 35 d after hatch, with a difference in the BW of birds belonging to the 18.5 and 19.0 doi groups up to day 35 after hatch. There was a significant effect of injection type on BW gain, feed intake, and FCR between 0 and 28 d after hatch. Between 0 and 35 d, FCR was lower in the vaccine-injected group in comparison with the noninjected and diluent control groups. Furthermore, total intestine coccidia and lesion indices were higher in the vaccine-18.5 treatment group in comparison with the diluent-18.5 treatment group at 28 d. In conclusion, hatchling weight was affected by injection age, and this subsequently affected growth performance. Furthermore, intestinal coccidia cycling peaked at 28 d, resulting in a reduction in growth performance through 28 d and subsequent compensatory growth by 35 d. There was no significant difference in coccidiosis cycling between the vaccine-18.5 and vaccine-19.0 doi treatment combination groups.
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Affiliation(s)
- A O Sokale
- Department of Poultry Science, Mississippi State University 39762, USA
| | - C J Williams
- Zoetis Animal Health, Research Triangle Park, NC 27703, USA
| | - F J Hoerr
- Veterinary Diagnostic Pathology, LLC, Fort Valley, VA 22652, USA
| | - K E C Collins
- Department of Poultry Science, Mississippi State University 39762, USA
| | - E D Peebles
- Department of Poultry Science, Mississippi State University 39762, USA.
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Mtshali SA, Adeleke MA. A review of adaptive immune responses to Eimeria tenella and Eimeria maxima challenge in chickens. WORLD POULTRY SCI J 2020. [DOI: 10.1080/00439339.2020.1833693] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Affiliation(s)
- S. A. Mtshali
- Discipline of Genetics, School of Life Sciences, University of Kwa-Zulu Natal, Durban, South Africa
| | - M. A. Adeleke
- Discipline of Genetics, School of Life Sciences, University of Kwa-Zulu Natal, Durban, South Africa
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Snyder RP, Guerin MT, Hargis BM, Page G, Barta JR. Monitoring coccidia in commercial broiler chicken flocks in Ontario: comparing oocyst cycling patterns in flocks using anticoccidial medications or live vaccination. Poult Sci 2020; 100:110-118. [PMID: 33357673 PMCID: PMC7772663 DOI: 10.1016/j.psj.2020.09.072] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2020] [Revised: 09/18/2020] [Accepted: 09/29/2020] [Indexed: 11/02/2022] Open
Abstract
Coccidiosis, the parasitic disease caused by Eimeria spp., is controlled during broiler chicken production through the inclusion of in-feed anticoccidial medications. Live-coccidiosis vaccination has become an increasingly common alternative to these medications. Monitoring infections with Eimeria spp. in flocks can be accomplished through determining the concentration of oocysts excreted in the fecal material (i.e., oocysts per gram; OPG). The purpose of our study was to sample commercial Ontario broiler chicken flocks at various times of the year to determine weekly OPG counts for flocks that use either an in-feed anticoccidial medication or a live-coccidiosis vaccine. Weekly sampling of 95 flocks from placement to market permitted documentation of oocyst cycling patterns typical of conventional and antibiotic-free flocks, and variation of these patterns in summer and winter. Medicated flocks had higher and later peak oocyst shedding compared with vaccinated flocks. Flocks reared in the summer peaked in oocyst shedding earlier than flocks reared in the winter. Despite what appears to be poorer coccidiosis control in the medicated flocks, the performance data were similar for these flocks compared with vaccinated flocks. This is the first study describing typical patterns of parasite shedding in Ontarian commercial broiler chicken flocks; these data will provide a baseline of expected Eimeria spp. infections in Canadian broiler chicken flocks to ensure optimal coccidiosis prevention.
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Affiliation(s)
- R P Snyder
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario N1G 2W1, Canada.
| | - M T Guerin
- Department of Population Medicine, Ontario Veterinary College, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - B M Hargis
- Division of Agriculture, Department of Poultry Science, University of Arkansas, Fayetteville, USA
| | - G Page
- Research and Development, Trouw Nutrition, Amersfoort, 3800 AG, The Netherlands
| | - J R Barta
- Department of Pathobiology, Ontario Veterinary College, University of Guelph, Guelph, Ontario N1G 2W1, Canada
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Parent E, Archambault M, Moore RJ, Boulianne M. Impacts of antibiotic reduction strategies on zootechnical performances, health control, and Eimeria spp. excretion compared with conventional antibiotic programs in commercial broiler chicken flocks. Poult Sci 2020; 99:4303-4313. [PMID: 32867974 PMCID: PMC7597979 DOI: 10.1016/j.psj.2020.05.037] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2020] [Revised: 05/12/2020] [Accepted: 05/22/2020] [Indexed: 11/23/2022] Open
Abstract
Increasing efforts have been made in recent years to reduce antimicrobial use in animal production. The objective of this prospective study was to evaluate, in commercial broiler chicken farms, 2 antibiotic reduction strategies that eliminated the use of antibiotics important for human medicine, in comparison with the conventional use of antibiotics. On 7 broiler chicken farms, a house was allocated to the antibiotic reduction treatments for 6 consecutive flocks, whereas a similar house on the same premises was assigned to the conventional use of antibiotics (CONV) for 6 consecutive flocks. The antibiotic reduction strategies consisted of continuous in-feed use of ionophores (TX1) and continuous in-feed use of ionophores with butyric acid (TX2). In the 84 flocks, zootechnical performance was recorded, lesion scoring at 21 and 28 D of age was performed, and fecal samples were recovered during grow out for Eimeria spp. oocysts counts. There was no statistical difference between TX1, TX2, and CONV for weights at slaughter, feed conversion ratios, average daily gains, age at slaughter, total mortalities, and condemnations. The probability of identifying oocysts in the fecal samples significantly increased with the age of the flock, but there was no significant treatment effect between 7 and 16 D of age. At 19 D of age, the probability of a sample containing oocysts was higher in TX1 than in CONV, but TX2 was not statistically different from TX1 and CONV. Predicted oocysts per gram in CONV flocks were significantly lower between 22 and 34 D of age than in TX1 and TX2 flocks, whereas there were no significant differences between TX1 and TX2 for all ages. Lesion scoring of the gastrointestinal system showed no differences for coccidiosis scores between TX1, TX2, and CONV. No lesions of necrotic enteritis were observed. In conclusion, it was possible to adequately control intestinal diseases and maintain zootechnical performances by relying exclusively on ionophores, when compared with broiler chicken flocks using standard shuttle programs with antibiotic growth promoters.
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Affiliation(s)
- Eric Parent
- Chair in Poultry Research, Faculty of Veterinary Medicine, University of Montreal, St-Hyacinthe, Québec, Canada; Porcine and Poultry Infectious Disease Research Center (CRIPA-FRQNT), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Québec, Canada
| | - Marie Archambault
- Porcine and Poultry Infectious Disease Research Center (CRIPA-FRQNT), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Québec, Canada
| | - Robert J Moore
- School of Science, RMIT University, Bundoora, Victoria 3083, Australia
| | - Martine Boulianne
- Chair in Poultry Research, Faculty of Veterinary Medicine, University of Montreal, St-Hyacinthe, Québec, Canada; Porcine and Poultry Infectious Disease Research Center (CRIPA-FRQNT), Faculty of Veterinary Medicine, University of Montreal, Saint-Hyacinthe, Québec, Canada.
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Maria Cardinal K, Kipper M, Andretta I, Machado Leal Ribeiro A. Withdrawal of antibiotic growth promoters from broiler diets: performance indexes and economic impact. Poult Sci 2020; 98:6659-6667. [PMID: 31544941 PMCID: PMC8913991 DOI: 10.3382/ps/pez536] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Accepted: 09/05/2019] [Indexed: 11/20/2022] Open
Abstract
This study aimed to estimate the productive and economic impacts caused by the withdrawal of antibiotic growth promoters (AGP) from broilers diet. Indexed publications that compared diets with or without AGP (AGP+/AGP-) for broilers (from initial to final phase) were collected and the results of feed intake, weight gain, and feed conversion were compiled in a database. A meta-analysis was performed following sequential analyses: graphical approach (to observe biological data coherence), correlation (to identify related factors), and variance-covariance (to compare groups). The annual number of broiler slaughtered in Brazil, target weight gain and feed conversion for each phase, the variation in feed conversion, feed cost, and AGP costs were used to build a model to estimate the effects of the AGP withdrawal on feeding costs. The database comprised 174 scientific articles containing 183 experiments, totaling 121,643 broilers, most of which were Ross (52% of the studies). The most frequent AGP sources/forms in the database were Avilamycin (41% of the AGP+ treatments), Flavomycin (19%), Virginiamycin (16%), and Bacitracin (14%). Higher feed intake, weight gain, and lower feed conversion were attributed (P < 0.05) to AGP+ diets during Initial phase (1 to 21 D). In Final phase (22 to 42 D) no differences were observed in performance variables. Treatments AGP+ presented higher weight gain and better feed conversion in the Total period (1 to 42 D). The results of feed conversion were improved (P < 0.05) with Avilamycin and Flavomycin; Virginiamycin improved weight gain and feed conversion. In the Total period, the economic impact was $0.03 per animal and a total of $183,560,232 per year. It was concluded that broilers fed AGP+ diets have higher weight gain and better feed conversion than those fed AGP- diets, and withdrawing AGP increases production costs.
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Affiliation(s)
- Katia Maria Cardinal
- Department of Animal Science, Universidade Federal do Rio Grande do Sul, Porto Alegre, Av. Bento Gonçalves, 7712 - Agronomia, CEP: 91540-000, Rio Grande do Sul, Brazil
| | - Marcos Kipper
- Department of Animal Science, Universidade Federal do Rio Grande do Sul, Porto Alegre, Av. Bento Gonçalves, 7712 - Agronomia, CEP: 91540-000, Rio Grande do Sul, Brazil
| | - Ines Andretta
- Department of Animal Science, Universidade Federal do Rio Grande do Sul, Porto Alegre, Av. Bento Gonçalves, 7712 - Agronomia, CEP: 91540-000, Rio Grande do Sul, Brazil
| | - Andréa Machado Leal Ribeiro
- Department of Animal Science, Universidade Federal do Rio Grande do Sul, Porto Alegre, Av. Bento Gonçalves, 7712 - Agronomia, CEP: 91540-000, Rio Grande do Sul, Brazil
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