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Molecular characterization and analysis of drug resistance-associated protein enolase 2 of Eimeria tenella. Int J Parasitol Drugs Drug Resist 2023; 21:81-90. [PMID: 36764225 PMCID: PMC9929201 DOI: 10.1016/j.ijpddr.2023.01.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2022] [Revised: 01/30/2023] [Accepted: 01/31/2023] [Indexed: 02/05/2023]
Abstract
Eimeria tenella, an intestinal parasite, has brought huge economic losses to the poultry industry. The prevalence and severity of the development of drug resistance has increased the challenge of coccidiosis control. We previously identified the enolase 2 of E. tenella (EtENO2) was differentially expressed in drug-sensitive (DS) and drug-resistant strains using RNA-seq. In this study, the expression of EtENO2 in diclazuril-resistant (DZR), maduramicin-resistant (MRR), and salinomycin-resistant (SMR) strains was analyzed by quantitative real-time PCR (qRT-PCR) and western blots. EtENO2 was highly expressed in several drug-resistant strains compared with the DS strain. The qRT-PCR showed that the transcription level of EtENO2 in the field-isolated resistant strains was upregulated compared with the DS strain. The enzyme activity results indicated that the catalytic activity of EtENO2 in the drug-resistant strains was higher than in the DS strain. In addition, qRT-PCR and western blots showed that the expression level of EtENO2 was higher in second generation merozoites (SM) and unsporulated oocysts (UO) than that in sporozoites (SZ) and sporulated oocysts (SO). Immunofluorescence localization revealed that EtENO2 was distributed throughout SZ and SM and on the surface of the parasites. After the SZ invasion DF-1 cells, it was also observed on the parasitophorous vacuole membrane. Our secretion experiments found that EtENO2 could be secreted outside the SZ. This study indicated that EtENO2 might be related to the interaction between E. tenella and host cells and be involved in the development of E. tenella resistance to some anticoccidial drugs.
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2
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Klobucher KN, Badger R, Foxall T, Erickson PS. Short Communication: effect of sodium butyrate, monensin, and butyric acid on the viability of Eimeria bovis sporozoites and their degree of damage to a bovine epithelial cell line. J Anim Sci 2022; 100:skac360. [PMID: 36315476 PMCID: PMC9733496 DOI: 10.1093/jas/skac360] [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: 08/09/2022] [Accepted: 10/28/2022] [Indexed: 11/05/2022] Open
Abstract
This study aimed to determine the viability of sporozoites from Eimeria bovis when exposed to sodium butyrate (SB), monensin (MON), or butyric acid (BA), and to determine the effects of SB on sporozoite invasion of cells in comparison to MON as measured by the damage to a bovine epithelial cell line. To determine viability, isolated sporozoites were suspended in one of four treatments: control (CON) of cell culture medium alone, SB = 0.028 mg/mL suspended in control medium, MON = 0.01 mg/mL suspended in CON, and BA = 0.18 mg/mL suspended in CON. The number of live sporozoites was less for the MON and BA treatments compared to the CON and SB treatments. The number of dead sporozoites was similar regardless of treatment. There was a trend for treatment to affect the percent sporozoite viability. Control, SB and BA treatments were similar, while MON compared to control and SB had decreased percent viability. Results for MON, when compared to BA, were similar for percent viability. Lactate dehydrogenase (LDH) release was used to determine cellular damage to Madin Darby Bovine Kidney (MDBK) cells when exposed to E. bovis sporozoites in vitro. Cells were exposed to similar numbers of sporozoites and treated with: CON, SB = 0.028 mg/mL in control medium, MON = 0.01 mg/mL in control medium. Control LDH result (with sporozoites) was greater than both the SB and MON treatments while the LDH for SB and Mon and cells not exposed to sporozoites were similar. SB and MON were both shown to decrease cellular damage to MDBK cells as determined by decreased LDH release. SB has the potential to act as an anticoccidial alternative to MON.
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Affiliation(s)
- Katrina N Klobucher
- Department of Agriculture, Nutrition, and Food Systems, University of New Hampshire, Durham, NH, USA
| | - Rachel Badger
- Department of Biological Sciences, University of New Hampshire, Durham, NH 03824, USA
| | - Thomas Foxall
- Department of Biological Sciences, University of New Hampshire, Durham, NH 03824, USA
| | - Peter S Erickson
- Department of Agriculture, Nutrition, and Food Systems, University of New Hampshire, Durham, NH, USA
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3
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Aguinaga-Casañas MA, Mut-Salud N, Falcón-Piñeiro A, Alcaraz-Martínez Á, Guillamón E, Baños A. In Vitro Antiparasitic Activity of Propyl-Propane-Thiosulfinate (PTS) and Propyl-Propane-Thiosulfonate (PTSO) from Allium cepa against Eimeria acervulina Sporozoites. Microorganisms 2022; 10:microorganisms10102040. [PMID: 36296317 PMCID: PMC9607501 DOI: 10.3390/microorganisms10102040] [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: 09/09/2022] [Revised: 10/06/2022] [Accepted: 10/11/2022] [Indexed: 11/16/2022] Open
Abstract
Among the alternatives to control avian coccidiosis, alliaceous extracts stand out due to their functional properties. Despite this, most of the references are focused just on garlic. In this study, we analyze the in vitro effects of propyl-propane thiosulfinate (PTS) and propyl-propane thiosulfonate (PTSO), two organosulfur compounds from onion, on MDBK cells infected with sporozoites of Eimeria acervulina. To this aim, two different experiments were performed. In the first experiment, sporozoites were previously incubated for 1 h at 1, 5 and 10 µg/mL of PTS or PTSO and added to MDBK cells. In the second experiment, MDBK cells were first incubated for 24 h at different concentrations of PTS or PTSO and then infected with E. acervulina sporozoites. Then, 24 h after inoculation, the presence of E. acervulina was quantified by qPCR. MDBK viability was measured at 72 h post-infection. Sporozoites incubated at 10 µg/mL of PTS and PTSO inhibited the capability to penetrate the cells up to 75.2% ± 6.44 and 71.7% ± 6.03, respectively. The incubation of MDBK with each compound resulted in a preventive effect against sporozoite invasion at 1 µg/mL of PTS and 1 and 10 µg/mL of PTSO. Cells incubated with PTSO obtained similar viability percentages to uninfected cells. These results suggest that the use of PTS and PTSO is a promising alternative to coccidiosis treatment, although further in vivo studies need to be performed.
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Affiliation(s)
| | - Nuria Mut-Salud
- Department of Microbiology and Biotechnology, DMC Research Center, Camino de Jayena s/n, 18620 Granada, Spain
| | - Ana Falcón-Piñeiro
- Department of Microbiology and Biotechnology, DMC Research Center, Camino de Jayena s/n, 18620 Granada, Spain
| | | | - Enrique Guillamón
- Department of Microbiology and Biotechnology, DMC Research Center, Camino de Jayena s/n, 18620 Granada, Spain
| | - Alberto Baños
- Department of Microbiology and Biotechnology, DMC Research Center, Camino de Jayena s/n, 18620 Granada, Spain
- Department of Microbiology, University of Granada, Fuente Nueva s/n, 18071 Granada, Spain
- Correspondence:
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4
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Bangoura B, Bhuiya MAI, Kilpatrick M. Eimeria infections in domestic and wild ruminants with reference to control options in domestic ruminants. Parasitol Res 2022; 121:2207-2232. [PMID: 35680677 DOI: 10.1007/s00436-022-07564-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2021] [Accepted: 05/28/2022] [Indexed: 10/18/2022]
Abstract
Eimeria infections are commonly seen in a variety of mammalian hosts. This genus of unicellular sporozoan parasites causes significant disease (coccidiosis) in different livestock species leading to economic losses for agricultural producers. Especially the production of cattle, sheep, and goat is strongly dependent on efficient coccidiosis control. However, many other livestock hosts like, e.g., camelids, bison, rabbits, and guinea pigs may benefit from reduced parasite transmission and targeted control measures as well. Besides livestock, also wildlife and pet animals may be affected by Eimeria infections resulting in clinical or subclinical coccidiosis. Wildlife herd health is crucial to conservation efforts, and Eimeria species are a prevalent pathogen in multiple mammalian wildlife species. This review aims to highlight the epidemiology of mammalian Eimeria infections in both wild and domestic ruminants, including host specificity, transmission, survival of environmental oocysts, occurrence, and risk factors for infection. Understanding general drivers of Eimeria infection may support adequate livestock and wildlife management. Furthermore, control options for livestock with reference to management factors, drug application, and alternative approaches are discussed. The goal of Eimeria control should be to reduce pathogen transmission in different host species and to improve sustainable livestock production. Controlling Eimeria infections in livestock is important considering both their animal welfare impact and their high economic relevance.
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Affiliation(s)
- Berit Bangoura
- Department of Veterinary Sciences, College of Agriculture and Natural Resources, University of Wyoming, Laramie, WY, 82070, USA.
| | - Md Ashraful Islam Bhuiya
- Department of Veterinary Sciences, College of Agriculture and Natural Resources, University of Wyoming, Laramie, WY, 82070, USA
| | - Michelle Kilpatrick
- Department of Veterinary Sciences, College of Agriculture and Natural Resources, University of Wyoming, Laramie, WY, 82070, USA
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5
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Li JY, Huang HB, Wang N, Shi CW, Pan TX, Zhang B, Yang GL, Wang CF. Sanguinarine induces apoptosis in Eimeria tenella sporozoites via the generation of reactive oxygen species. Poult Sci 2022; 101:101771. [PMID: 35272108 PMCID: PMC8913342 DOI: 10.1016/j.psj.2022.101771] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 01/21/2022] [Accepted: 01/22/2022] [Indexed: 10/25/2022] Open
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In Vitro Assessment of Anticoccidials: Methods and Molecules. Animals (Basel) 2021; 11:ani11071962. [PMID: 34209100 PMCID: PMC8300270 DOI: 10.3390/ani11071962] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Accepted: 06/25/2021] [Indexed: 12/13/2022] Open
Abstract
Simple Summary Coccidiosis is a major problem in poultry production, leading to significant economic losses. Due to the outbreak of resistance to the available treatments, research is focusing on finding new molecules that work against the pathogen. Botanical compounds represent promising alternatives, but reliable in vitro tests are needed for their screening and to understand their mechanism of action. Research in vitro involves studies on the environmental phase of the parasite and studies on the endogenous development, which occurs inside the host cells and that requires cell cultures or in ovo models to be studied. This review aims to summarize the protocols that have been successfully applied so far, as well as to suggest potential cues to improve research on this field. Moreover, as the surge of botanicals as anticoccidial molecules is on the rise, the intent is to provide an overview of the methods to assess their effectiveness in vitro in comparison with conventional drugs. Abstract Avian coccidiosis is a disease causing considerable economic losses in the poultry industry. It is caused by Eimeria spp., protozoan parasites characterized by an exogenous–endogenous lifecycle. In vitro research on these pathogens is very complicated and lacks standardization. This review provides a description of the main in vitro protocols so far assessed focusing on the exogenous phase, with oocyst viability and sporulation assays, and on the endogenous phase, with invasion and developmental assays in cell cultures and in ovo. An overview of these in vitro applications to screen both old and new remedies and to understand the relative mode of action is also discussed.
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7
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Molecular characterization and analysis of the ATPase ASNA1 homolog gene of Eimeria tenella in a drug sensitive strain and drug resistant strains. INTERNATIONAL JOURNAL FOR PARASITOLOGY-DRUGS AND DRUG RESISTANCE 2021; 15:115-125. [PMID: 33639573 PMCID: PMC7910411 DOI: 10.1016/j.ijpddr.2021.02.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 02/03/2021] [Accepted: 02/08/2021] [Indexed: 02/03/2023]
Abstract
The widespread use of drugs has exacerbated the resistance of Eimeria tenalla to anti-coccidial drugs. Using RNA-seq, we previously found the ATPase ASNA1 homolog of E. tenella (EtASNA1) was differentially expressed in resistant strains and drug sensitive (DS) strain. In our study, we used western blotting and quantitative real-time PCR (qRT-PCR) to analyze the translational and transcriptional levels of EtASNA1 in a diclazuril-resistant (DZR) strain, maduramicin-resistant (MRR) strain, salinomycin-resistant (SMR) strain, and DS strain and found EtASNA1 was highly expressed in three drug-resistant strains. The qRT-PCR and western blotting results also showed that the expression levels of EtASNA1 increased with increasing drug concentration, and the transcription levels of the DZR strains isolated from the field were higher than those of the DS strain. In addition, we used in vivo and in vitro tests to analyze the changes of EtASNA1 expression after DZR, MRR, and DS strain infections in chickens, and in vitro inoculation of DF-1 cells in the presence of drugs. The addition of drugs caused expression to be upregulated. The results of qRT-PCR and western blotting also showed that the expression levels of EtASNA1 in second-generation merozoites (SM) and unsporulated oocysts (UO) were significantly higher than those in the other two developmental stages. The immunofluorescence localization of EtASNA1 indicated that the protein was distributed throughout the sporozoites (SZ) and SM, except for the refractile bodies of SZ. In vitro inhibition experiments showed that anti-EtASNA1 antibody incubation significantly inhibited SZ invasion of DF-1 cells. The above results showed that EtASNA1 may be related to host cell invasion of E. tenella and may be involved in the development of E. tenella resistance to some drugs.
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8
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Gilbert W, Bellet C, Blake DP, Tomley FM, Rushton J. Revisiting the Economic Impacts of Eimeria and Its Control in European Intensive Broiler Systems With a Recursive Modeling Approach. Front Vet Sci 2020; 7:558182. [PMID: 33251254 PMCID: PMC7674784 DOI: 10.3389/fvets.2020.558182] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Accepted: 09/07/2020] [Indexed: 11/28/2022] Open
Abstract
Ionophore compounds active against Eimeria species are widely used in intensive broiler systems and have formed the backbone of coccidiosis control for almost 50 years. Producers, however, are under pressure to reduce ionophore use due to consumer concerns over antimicrobial usage in food animals, and antimicrobial resistance. Moreover, current vaccines against Eimeria are commonly considered to be less cost-effective in intensive broiler systems, especially in Europe where attenuated live vaccines are used. An economic assessment of the impact of Eimeria and the disease coccidiosis, including the cost implications of different efficacies of control, is therefore timely to provide evidence for industry and policy development. A mechanistic model of broiler production under varying infection and control states was used to construct a dataset from which system productivity can be measured. Coccidiosis impact increased rapidly as control efficacy decreased. In the total absence of control, median impact was found to maximize at between €2.55 and €2.97 in lost production per meter squared of broiler house over a 33 day growing period. Coccidiosis remains a major risk to intensive broiler systems and the model developed allows investigation of issues related to coccidiosis control, antimicrobial use and the development of antimicrobial resistance.
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Affiliation(s)
- William Gilbert
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Camille Bellet
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
| | - Damer P Blake
- Department of Pathobiology and Population Sciences, Royal Veterinary College, Hatfield, United Kingdom
| | - Fiona M Tomley
- Department of Pathobiology and Population Sciences, Royal Veterinary College, Hatfield, United Kingdom
| | - Jonathan Rushton
- Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, United Kingdom
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Marugan-Hernandez V, Jeremiah G, Aguiar-Martins K, Burrell A, Vaughan S, Xia D, Randle N, Tomley F. The Growth of Eimeria tenella: Characterization and Application of Quantitative Methods to Assess Sporozoite Invasion and Endogenous Development in Cell Culture. Front Cell Infect Microbiol 2020; 10:579833. [PMID: 33154954 PMCID: PMC7590826 DOI: 10.3389/fcimb.2020.579833] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2020] [Accepted: 09/07/2020] [Indexed: 01/03/2023] Open
Abstract
In vitro development of the complete life cycle of Eimeria species has been achieved in primary cultures of avian epithelial cells with low efficiency. The use of immortalized cell lines simplifies procedures but only allows partial development through one round of parasite invasion and intracellular replication. We have assessed the suitability of Madin-Darby Bovine Kidney (MDBK) cells to support qualitative and quantitative studies on sporozoite invasion and intracellular development of Eimeria tenella. Analysis of parasite ultrastructure by transmission electron microscopy and serial block face-scanning electron microscopy proved the suitability of the system to generate good quality schizonts and first-generation merozoites. Parasite protein expression profiles elucidated by mass spectrometry corroborated previous findings occurring during the development of the parasite such as the presence of alternative types of surface antigen at different stages and increased abundance of proteins from secretory organelles during invasion and endogenous development. Quantitative PCR (qPCR) allowed the tracking of development by detecting DNA division, whereas reverse transcription qPCR of sporozoite- and merozoite-specific genes could detect early changes before cell division and after merozoite formation, respectively. These results correlated with the analysis of development using ImageJ semi-automated image analysis of fluorescent parasites, demonstrating the suitability and reproducibility of the MDBK culture system. This systems also allowed the evaluation of the effects on invasion and development when sporozoites were pre-incubated with anticoccidial drugs, showing similar effects to those reported before. We have described through this study a series of methods and assays for the further application of this in vitro culture model to more complex studies of Eimeria including basic research on parasite cell biology and host-parasite interactions and for screening anticoccidial drugs.
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Affiliation(s)
| | - Georgia Jeremiah
- The Royal Veterinary College, University of London, London, United Kingdom
| | | | - Alana Burrell
- Electron Microscopy Science Technology Platform, The Francis Crick Institute, London, United Kingdom
| | - Sue Vaughan
- Department of Biological and Medical Sciences, Oxford Brookes University, Oxford, United Kingdom
| | - Dong Xia
- The Royal Veterinary College, University of London, London, United Kingdom
| | - Nadine Randle
- Department of Infection Biology, Institute of Infection & Global Health, University of Liverpool, Liverpool, United Kingdom
| | - Fiona Tomley
- The Royal Veterinary College, University of London, London, United Kingdom
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10
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Stahl TC, Hatungimana E, Klanderman KD, Moreland SC, Erickson PS. Sodium butyrate and monensin supplementation to postweaning heifer diets: Effects on growth performance, nutrient digestibility, and health. J Dairy Sci 2020; 103:10207-10218. [PMID: 32952029 DOI: 10.3168/jds.2020-18584] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2020] [Accepted: 07/01/2020] [Indexed: 12/17/2022]
Abstract
The objective of this study was to evaluate growth and performance of postweaning heifers supplemented with monensin (MON), sodium butyrate (SB), or the combination of MON and SB (MSB) compared with heifers not receiving these feed additives. Forty Holstein heifers [mean age 84.2 ± 1.2 d; body weight (BW) 99.8 ± 10.8 kg (mean ± SD)] were housed in a freestall barn, blocked by birth date, and randomly assigned to 1 of 4 treatments in a randomized complete block design. Treatments were (1) 100 g of soybean meal carrier (control; CON); (2) 0.75 g of SB/kg of BW + carrier (SB); (3) 1 mg of MON/kg of BW + carrier (MON); (4) 1 mg of MON/kg of BW + 0.75 g of SB/kg of BW (MSB). Data were analyzed using single degree of freedom contrasts evaluating CON versus additives (ADD), SB versus MON, and SB and MON versus MSB. Treatments were hand-mixed daily. Feed and orts were measured daily and frozen at -20°C. Orts samples were subsampled for dry matter (DM) determination, and total mixed ration samples were taken weekly and composited monthly for DM and nutrient analysis. Initial BW, heart and paunch girths, body length, blood samples, and fecal coccidia counts were measured before the start and weekly during the 12-wk trial. Blood samples were analyzed for glucose, plasma urea nitrogen (PUN), and ketone concentrations. Apparent total-tract nutrient digestibility was determined from d 21 to 27 and from d 63 to 69 using acid detergent insoluble ash as a marker. Daily dry matter intake (DMI) and metabolizable energy intake were increased in ADD compared with CON, and average BW, final BW, and heart girth tended to increase. Whereas MSB tended to be greater than SB and MON for heart girth, feed efficiency was greater with MON compared with SB. Compared with CON, ADD decreased coccidia counts. No effect of treatment on PUN was detected. Monensin and SB tended to have greater plasma glucose than MSB did. Average blood ketone concentrations were greater with ADD versus CON, in SB versus MON, and in MSB versus SB and MON. During the wk-3 digestibility phase, DMI tended to be greater in heifers fed SB versus MON, as well as in heifers fed MSB versus SB and MON. Digestibility of nutrients were similar, except that starch digestibility was increased in heifers fed MSB versus SB and MON. During the wk-9 digestibility phase, DMI and digestibility of nutrients were similar, except NDF, which tended to be greater in CON than in ADD. Overall, ADD resulted in positive growth and reduced coccidia compared with CON.
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Affiliation(s)
- T C Stahl
- Department of Agriculture, Nutrition, and Food Systems, University of New Hampshire, Durham, 03824
| | - E Hatungimana
- Department of Agriculture, Nutrition, and Food Systems, University of New Hampshire, Durham, 03824
| | | | | | - P S Erickson
- Department of Agriculture, Nutrition, and Food Systems, University of New Hampshire, Durham, 03824.
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11
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Yu Y, Zhao Q, Zhu S, Dong H, Huang B, Liang S, Wang Q, Wang H, Yu S, Han H. Molecular characterization of serine/threonine protein phosphatase of Eimeria tenella. J Eukaryot Microbiol 2020; 67:510-520. [PMID: 32358794 DOI: 10.1111/jeu.12798] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2020] [Revised: 04/13/2020] [Accepted: 04/23/2020] [Indexed: 12/17/2022]
Abstract
Avian coccidiosis is a widespread and economically significant poultry disease caused by several Eimeria species, including Eimeria tenella. Previously, E. tenella serine/threonine protein phosphatase (EtSTP) was found to be differentially expressed in drug-sensitive (DS) and drug-resistant strains using RNA-seq. In the present study, we found that transcription and translation levels of EtSTP were higher in diclazuril-resistant (DZR) strains and maduramicin-resistant (MRR) strains than in DS strains using quantitative real-time PCR (qPCR) and Western blotting. Enzyme activity results indicated that the catalytic activity of EtSTP was higher in the two drug-resistant strains than in DS strains. Western blot and qPCR analysis also showed that expression levels of EtSTP were higher in unsporulated oocysts (UO) and second-generation merozoites (SM). Indirect immunofluorescence localization showed that EtSTP was located in most areas of the parasite with the exception of refractile bodies, and fluorescence intensity was enhanced during development. In vitro inhibition experiments showed that the ability of sporozoites (SZ) to invade cells was significantly decreased after treatment with anti-rEtSTP antibody. These results indicated that EtSTP acted mainly during the developmental and reproductive stages of the parasite and may be related to the resistance of coccidia to external drug pressure.
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Affiliation(s)
- Yu Yu
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Minhang, Shanghai, 200241, China.,College of Life Sciences, Shanghai Normal University, Shanghai, 200234, China
| | - Qiping Zhao
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Minhang, Shanghai, 200241, China
| | - Shunhai Zhu
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Minhang, Shanghai, 200241, China
| | - Hui Dong
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Minhang, Shanghai, 200241, China
| | - Bing Huang
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Minhang, Shanghai, 200241, China
| | - Shanshan Liang
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Minhang, Shanghai, 200241, China.,College of Life Sciences, Shanghai Normal University, Shanghai, 200234, China
| | - Qingjie Wang
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Minhang, Shanghai, 200241, China
| | - Haixia Wang
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Minhang, Shanghai, 200241, China
| | - Shuilan Yu
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Minhang, Shanghai, 200241, China
| | - Hongyu Han
- Key Laboratory of Animal Parasitology of Ministry of Agriculture, Shanghai Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Minhang, Shanghai, 200241, China
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12
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Abstract
Ruminant coccidiosis, caused by Eimeria species, is a significant and widespread enteric disease in young livestock worldwide. High morbidities and significant mortalities may be observed. For disease diagnosis, fecal samples from clinically ill animals should be analyzed for both, identity (ie, pathogenicity) of Eimeria species and excreted oocyst amount. To prevent coccidiosis-related economic losses, management measures to reduce infection pressure and improve general animal health are crucial. Anticoccidial drugs are widely used to control clinical and subclinical disease. Treatment is most efficient when applied prophylactically or metaphylactically. To avoid development of parasite drug resistance, drugs should be used sustainably.
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13
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Chasser KM, Duff AF, Wilson KM, Briggs WN, Latorre JD, Barta JR, Bielke LR. Research Note: Evaluating fecal shedding of oocysts in relation to body weight gain and lesion scores during Eimeria infection. Poult Sci 2020; 99:886-892. [PMID: 32036984 PMCID: PMC7587844 DOI: 10.1016/j.psj.2019.10.028] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 10/10/2019] [Accepted: 10/13/2019] [Indexed: 11/06/2022] Open
Abstract
Coccidiosis has been a pervasive disease within the poultry industry, with test parameters used to measure effectiveness of treatment strategies often being subjective or influenced by non-disease-related activity. Four experiments were completed, which examined several test parameters of coccidiosis, including body weight gain (BWG), lesion scores, and oocysts per gram of feces (OPG). Each experiment included at least 2 parameters for measuring coccidial infection in chickens and turkeys. In experiment 1, an inoculated control was measured against 3 anticoccidial groups, whereas in experiments 2 to 4, noninoculated and inoculated controls were compared via BWG and OPG. Lesion scores were also included in experiments 1, 3, and 4. Experiment 4 resulted in high correlation, via Pearson correlation coefficient, between BWG and OPG (r = -0.69), very high correlation between OPG and lesion score (r = 0.86), and moderate correlation between BWG and lesion score (r = -0.49). Lesion scores proved to be effective in confirming Eimeria infection, although they did not correlate well with BWG or OPG. Each parameter tended to provide more useful information when lined up with the Eimeria life cycle. Incorporation of OPG, with BWG and lesion scores, as test parameters to measure coccidiosis intervention strategies, provides a global description of disease that may not otherwise be observed with the 2 latter measurements alone.
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Affiliation(s)
- K M Chasser
- Department of Animal Sciences, The Ohio State University, Columbus, OH
| | - A F Duff
- Department of Animal Sciences, The Ohio State University, Columbus, OH
| | - K M Wilson
- Department of Animal Sciences, The Ohio State University, Columbus, OH
| | - W N Briggs
- Department of Animal Sciences, The Ohio State University, Columbus, OH
| | - J D Latorre
- Department of Poultry Science, University of Arkansas, Fayetteville, AR
| | - J R Barta
- Department of Pathobiology, University of Guelph, Guelph, ON, Canada
| | - L R Bielke
- Department of Animal Sciences, The Ohio State University, Columbus, OH.
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14
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Affiliation(s)
- R. L. Reece
- Department of Agriculture and Rural Affairs, Veterinary Research Institute, Park Drive, Parkville, Victoria, 3052, Australia
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15
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Affiliation(s)
- W. W. Braunius
- Gezondheidsdienst voor Dieren, Postbus 10, 6880 BD Velp, the Netherlands
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16
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Noack S, Chapman HD, Selzer PM. Anticoccidial drugs of the livestock industry. Parasitol Res 2019; 118:2009-2026. [PMID: 31152233 PMCID: PMC6611755 DOI: 10.1007/s00436-019-06343-5] [Citation(s) in RCA: 119] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Accepted: 04/29/2019] [Indexed: 12/11/2022]
Abstract
Coccidiosis is a parasitic disease of a wide variety of animals caused by coccidian protozoa. The coccidia are responsible for major economic losses of the livestock industry. For example, the annual cost due to coccidiosis to the global poultry industry has been estimated to exceed US$ 3 billion annually. Currently available drugs for the control of this disease are either polyether ionophorous antibiotics that are derived from fermentation products, or synthetic compounds, produced by chemical synthesis. Unfortunately, no new drugs in either category have been approved for use for decades. Resistance has been documented for all those of the drugs currently employed and therefore the discovery of novel drugs with unique modes of action is imperative if chemotherapy is to remain the principal means to control this disease. This chapter aims to give an overview of the efficacy and mode of action of the current compounds used to control coccidiosis in livestock and provides a brief outlook of research needs for the future.
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Affiliation(s)
- Sandra Noack
- Boehringer Ingelheim Vetmedica GmbH, Ingelheim am Rhein, Germany
| | - H David Chapman
- Department of Poultry Science, University of Arkansas, Fayetteville, AR, USA
| | - Paul M Selzer
- Boehringer Ingelheim Vetmedica GmbH, Ingelheim am Rhein, Germany.
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17
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Thabet A, Zhang R, Alnassan AA, Daugschies A, Bangoura B. Anticoccidial efficacy testing: In vitro Eimeria tenella assays as replacement for animal experiments. Vet Parasitol 2016; 233:86-96. [PMID: 28043393 DOI: 10.1016/j.vetpar.2016.12.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2016] [Revised: 11/24/2016] [Accepted: 12/09/2016] [Indexed: 11/25/2022]
Abstract
SCOPE Availability of an accurate in vitro assay is a crucial demand to determine sensitivity of Eimeria spp. field strains toward anticoccidials routinely. In this study we tested in vitro models of Eimeria tenella using various polyether ionophores (monensin, salinomycin, maduramicin, and lasalocid) and toltrazuril. Minimum inhibitory concentrations (MIC95, MIC50/95) for the tested anticoccidials were defined based on a susceptible reference (Houghton strain), Ref-1. In vitro sporozoite invasion inhibition assay (SIA) and reproduction inhibition assay (RIA) were applied on sensitive laboratory (Ref-1 and Ref-2) and field (FS-1, FS-2, and FS-3) strains to calculate percent of inhibition under exposure of these strains to the various anticoccidials (%ISIA and%IRIA, respectively). The in vitro data were related to oocyst excretion, lesion scores, performance, and global resistance indices (GI) assessed in experimentally infected chickens. RESULTS Polyether ionophores applied in the RIA were highly effective at MIC95 against Ref-1 and Ref-2 (%IRIA≥95%). In contrast, all tested field strains displayed reduced to low efficacy (%IRIA<95%).%IRIA values significantly correlated with oocyst excretion determined in the animal model (p<0.01) for polyether ionophores. However, this relationship could not be demonstrated for toltrazuril due to unexpected lack of in vitro sensitivity in Ref-2 (%IRIA=56.1%). In infected chickens, toltrazuril was generally effective (GI>89%) against all strains used in this study. However, adjusted GI (GIadj) for toltrazuril-treated groups exhibited differences between reference and field strains which might indicate varying sensitivity. CONCLUSION RIA is a suitable in vitro tool to detect sensitivity of E. tenella towards polyether ionophores, and may thus help to reduce, replace, or refine use of animal experimentation for in vivo sensitivity assays.
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Affiliation(s)
- Ahmed Thabet
- Institute of Parasitology, Faculty of Veterinary Medicine, Centre for Infectious Diseases, Leipzig University, Germany
| | - Runhui Zhang
- Institute of Parasitology, Faculty of Veterinary Medicine, Centre for Infectious Diseases, Leipzig University, Germany
| | | | - Arwid Daugschies
- Institute of Parasitology, Faculty of Veterinary Medicine, Centre for Infectious Diseases, Leipzig University, Germany
| | - Berit Bangoura
- Institute of Parasitology, Faculty of Veterinary Medicine, Centre for Infectious Diseases, Leipzig University, Germany.
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18
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Ultrastructural effects of acetamizuril on endogenous phases of Eimeria tenella. Parasitol Res 2015; 115:1245-52. [DOI: 10.1007/s00436-015-4861-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2015] [Accepted: 11/27/2015] [Indexed: 01/24/2023]
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19
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Thabet A, Alnassan AA, Daugschies A, Bangoura B. Combination of cell culture and qPCR to assess the efficacy of different anticoccidials on Eimeria tenella sporozoites. Parasitol Res 2015; 114:2155-63. [PMID: 25773180 DOI: 10.1007/s00436-015-4404-4] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2015] [Accepted: 02/27/2015] [Indexed: 11/30/2022]
Abstract
Three in vitro studies were designed to develop an assay for anticoccidial efficacy by use of laboratory (Houghton) and field (T-376) Eimeria tenella strains. In study (1), minimum inhibitory concentrations (MICs) of monensin (Mon), maduramicin (Mad), salinomycin (Sal), and lasalocid (Las) were determined that are able to inhibit more than 50% of sporozoites in host cell (Madin-Darby bovine kidney (MDBK)) penetration and more than 95% of Houghton sporozoites development to mature merozoites (treatment time 24 h) using quantitative real-time PCR (qPCR). MICs were 0.5, 2.5, 1, and 0.5 μg/ml for Mon, Mad, Sal, and Las, respectively. Applying the previous MIC on T-376 strain revealed a different sensitivity profile. Mad reduced T-376 gene copies by only 89.3% after 96 h of infection. In study (2), Houghton strain sporozoites were incubated with MIC of the different tested ionophores for 2 and 4 h, respectively; afterwards, their ability to invade MDBK cells was determined using phase-contrast microscopy and qPCR. Treatment of sporozoites with ionophores for 4 h resulted in significant inhibition of invasion compared with non-treated parasites as assessed both by microscopy as well as qPCR. Inhibition rates for Mon, Mad, Sal, and Las were 90.2, 75.0, 88.3, and 82.6% using phase-contrast microscopy and 83.9, 81.4, 85.8, and 75.4% using qPCR, respectively. T-376 sporozoite invasion into MDBK cells was reduced to 48.9% by Mad. Study (3) was conducted to determine inhibition exerted by toltrazuril (Tol). Tol at 5 μg/ml reduced reproduction of Houghton strain by 95%, whereas T-376 was only reduced by 86.5%. The presented experiments indicate that infectivity inhibition of sporozoites incubated for 4 h with anticoccidials and development inhibition after 96 h of infection by qPCR are suitable means to assess sensitivity of E. tenella strains to anticoccidials.
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Affiliation(s)
- Ahmed Thabet
- Institute of Parasitology, Faculty of Veterinary Medicine, Centre for Infectious Diseases, University Leipzig, Leipzig, Germany
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20
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Chapman H, Jeffers T, Williams R. Forty years of monensin for the control of coccidiosis in poultry. Poult Sci 2010; 89:1788-801. [DOI: 10.3382/ps.2010-00931] [Citation(s) in RCA: 187] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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21
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Carpenter JW, Novilla MN, Hatfield JS. EFFICACY OF SELECTED COCCIDIOSTATS IN SANDHILL CRANES (GRUS CANADENSIS) FOLLOWING CHALLENGE. J Zoo Wildl Med 2005; 36:391-400. [PMID: 17312756 DOI: 10.1638/02-051.1] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
The anticoccidial efficacy of amprolium, clazuril, and monensin were studied in sandhill cranes (Grus canadensis) infected with a mixture of Eimeria spp. oocysts. Five groups of four 1-day-old sandhill crane chicks were maintained on a crumbled ration containing no coccidiostat, amprolium at 2.2 ppm, clazuril at 1.1 ppm, clazuril at 5.5 ppm, or monensin at 99 ppm. After 2 wk on their respective feeding regimens, birds in each of the five groups were administered 25 x 10(3) pooled sporulated Eimeria spp. oocysts per os and observed for another 3 wk. A sixth group of four chicks served as nonmedicated, nonchallenged control during the study. Clinical signs and lesions consistent with disseminated visceral coccidiosis were observed in all challenged controls and birds fed amprolium and clazuril. Birds in these groups died 9-10 days after challenge. In contrast, only one monensin-medicated bird had clinical signs of disseminated visceral coccidiosis, and it died 13 days after challenge (DAC). This and an asymptomatic bird that were necropsied at study termination had less-severe gross and microscopic lesions of disseminated visceral coccidiosis. Two of three monensin-treated birds that survived challenge passed from 50 to 500 coccidial oocysts 11 to 18 DAC but were negative at study termination. Of the coccidiostats tested, monensin, at the dietary level of 99 ppm, was the only anticoccidial drug that provided protection against experimentally induced disseminated visceral coccidiosis in sandhill cranes.
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Affiliation(s)
- James W Carpenter
- Department of Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, Kansas 66505, USA
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22
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The influence of a diet of mixed feed containing zeolite on the course of cecal coccidiosis in broilers. ACTA VET-BEOGRAD 2003. [DOI: 10.2298/avb0306377n] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
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23
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Raether W, Mehlhorn H, Hofmann J, Bräu B, Ehrlich K. Flow cytometric analysis of Eimeria tenella sporozoite populations exposed to salinomycin sodium in vitro: a comparative study using light and electron microscopy and an in vitro sporozoite invasion-inhibition test. Parasitol Res 1991; 77:386-94. [PMID: 1891447 DOI: 10.1007/bf00931633] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Eimeria tenella sporozoites exposed to 100, 70, 60 and 50 micrograms salinomycin sodium (SAL)/ml medium 199 at 41 degrees C and then stained with propidium iodide/fluorescein diacetate were analysed by means of flow cytometry (FCM). After 20 min exposure, they showed dose-dependent alterations in their size and shape, i.e. ballooning of most cells, and enhanced intracellular esterase activity as compared with untreated controls. After longer exposure periods (40 and 70 min), inflated cells gradually changed into shrivelled or crumpled, nonviable ones, thereby showing a gradual decrease in esterase activity and a gradual loss of membrane integrity (RFA+). As compared with untreated controls, sporozoites treated with 10 micrograms SAL/ml showed negligible RFA+ values (0.4%-2%), whereas those exposed to 1 and 0.1 microgram SAL ml and to the solvent dimethylsulfoxide (DMSO, 1%) did not, even after 70 min exposure. Slight to severe structural changes manifesting as an extremely wavy surface (1 microgram SAL/ml), vacuolization of the cytoplasm, distension or destruction of the mitochondrion and rupture of cell membranes (10 micrograms SAL/ml) were seen not only at higher SAL concentrations but also (rarely) at lower ones. The ability of sporozoites to invade primary chick-kidney cells was significantly inhibited by 70, 60 and 50 micrograms SAL/ml. In general, there were close relationships between findings obtained using FCM, electron microscopy and an invasion-inhibition test. The results indicate that FCM is a reliable and sensitive technique for characterizing the parasiticidal effects on and the possible mode of action of drugs in free coccidian sporozoites.
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Affiliation(s)
- W Raether
- Hoechst AG, Frankfurt/Main, Federal Republic of Germany
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24
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Daszak P, Ball SJ, Pittilo RM, Norton CC. Ultrastructural studies of the effects of the ionophore lasalocid on Eimeria tenella in chickens. Parasitol Res 1991; 77:224-9. [PMID: 2047368 DOI: 10.1007/bf00930862] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The ultrastructural development of Eimeria tenella was studied in experimentally infected chicks fed 90 ppm lasalocid, an ionophorous anticoccidial antibiotic. Drug treatment was timed to target-specific endogenous stages. At 6 h after infection, many sporozoites within the epithelium showed degradation as a result of drug action. Only a few intact sporozoites were seen. The drug caused outer-membrane blistering, large surface swellings and enlarged mitochondria in both first- and second-generation merozoites. No effect on the gamonts was discerned.
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Affiliation(s)
- P Daszak
- Division of Microbiology and Genetics, School of Science, Polytechnic of East London, UK
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25
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Guyonnet V, Johnson JK, Long PL. Studies on the stage of action of lasalocid against Eimeria tenella and Eimeria acervulina in the chicken. Vet Parasitol 1990; 37:93-100. [PMID: 2251751 DOI: 10.1016/0304-4017(90)90064-i] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Broiler chickens in battery pens were either fed a diet containing 100 ppm lasalocid or no drug for 24 h prior to inoculation with sporulated oocysts of Eimeria tenella or Eimeria acervulina. Different groups of birds remained on medicated feed for 24, 48, 72, 96, 120 or 144 h after inoculation. Conversely, other groups started on an unmedicated diet, were given medicated feed at different times after oocyst inoculation. Starting lasalocid medication 24 h (E. tenella) or 48 h (E. acervulina) after inoculation reduced the lesions and improved the weight gain. There was no significant difference in performance of birds after withdrawal of the drug at 48 h (E. tenella) or 72 h (E. acervulina) and thereafter. Starting lasalocid medication at 96 or 120 h did not suppress but rather reduced oocyst production.
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Affiliation(s)
- V Guyonnet
- Department of Poultry Science, University of Georgia, Athens 30602
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26
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Ball SJ, Pittilo RM, Johnson J, Long PL. Effect of lasalocid on the development of Eimeria tenella in chicken embryos. Vet Parasitol 1990; 36:337-41. [PMID: 2399654 DOI: 10.1016/0304-4017(90)90046-e] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Sporozoites of Eimeria tenella were treated with lasalocid in vitro and their viability tested by inoculating them into the allantoic cavity of 11-day-old chicken embryos. Concentrations of 0.1, 1.0 and 10.0 micrograms ml-1 reduced sporozoite viability, as judged by oocyst production. Injections into the embryos of 5, 50 or 500 micrograms of lasalocid 92-93 h after infection also reduced oocyst production, indicating activity against the later stages of the life cycle.
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Affiliation(s)
- S J Ball
- Department of Biosciences, Polytechnic of East London, U.K
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27
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Riddell FG, Tompsett SJ. The transport of Na+ and K+ ions through phospholipid bilayers mediated by the antibiotics salinomycin and narasin studied by 23Na- and 39K-NMR spectroscopy. BIOCHIMICA ET BIOPHYSICA ACTA 1990; 1024:193-7. [PMID: 2337616 DOI: 10.1016/0005-2736(90)90225-d] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Addition of the ionophoric antibiotics salinomycin or narasin to preparations of large unilamellar vesicles made from egg yolk phosphatidylcholine in sodium or potassium chloride solutions gives rise to dynamic effects in the 23Na- and 39K-NMR spectra. The dynamic spectra arise from the ionophore-mediated transport of the metal ions through the membrane. The kinetics of the transport are followed as a function of the concentrations of ionophore and the metal ion and are compatible in all cases with a model in which one ionophore molecule transports one metal ion. For both ionophores the transport of potassium ions is appreciably faster than that of sodium and in both cases the rate-limiting step for sodium transport is dissociation of the ionophore-metal complex. Assuming dissociation to be rate limiting in all four cases it is shown that the transport rate differences between the pairs of complexes of each metal arise solely from differences in the rates of formation. The stability constants for ionophore-metal complex formation in the membrane/water interface are evaluated.
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Affiliation(s)
- F G Riddell
- Department of Chemistry, University of St Andrews, U.K
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28
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Buxton D, Blewett DA, Trees AJ, McColgan C, Finlayson J. Further studies in the use of monensin in the control of experimental ovine toxoplasmosis. J Comp Pathol 1988; 98:225-36. [PMID: 3372754 DOI: 10.1016/0021-9975(88)90021-7] [Citation(s) in RCA: 72] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Monensin was fed to 69 pregnant ewes from 81 to 84 days gestation until lambing, at an estimated rate of nil, 16.8 or 27.9 mg per head per day. Ten days after the start of this regime, groups of the ewes were dosed orally with nil, 2000 or 12,000 sporulated Toxoplasma gondii oocysts. Twenty ewes given T. gondii alone (T ewes) produced 29 lambs or aborted foetuses, 16 (55.2 per cent) of which were born dead. The 39 ewes given monensin and T. gondii (M + T ewes) produced 48 lambs or aborted foetuses, 8 (16.7 per cent) of which were born dead. The 10 ewes given monensin alone produced 12 live lambs. No difference of effect was apparent between the two doses of monensin given, nor between the two doses of Toxoplasma oocysts used. Monensin alone caused no discernible problems. Not only were proportionately more live lambs born to M + T ewes than to T ewes, but they were also heavier, possibly due to a lesser "weight" of infection within the gravid uterus. We conclude that monensin fed at about 16 mg per head per day to pregnant ewes can significantly reduce losses at lambing time due to experimentally administered T. gondii.
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Affiliation(s)
- D Buxton
- Moredun Research Institute, Edinburgh, U.K
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29
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Abstract
Coccidiosis could potentially cause enormous economic loss to the poultry industry, especially in the production of broiler chickens (see Box 1). Losses are currently minimized by chemotherapeutic treatment but the effectiveness of many drugs seems to be declining. In this article, Peter Long and Tom Jeffers discuss the future for coccidial chemotherapy, and the potential for immunological control methods.
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Affiliation(s)
- P L Long
- Department of Poultry Science, University of Georgia, Athens, GA 30602, USA
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30
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Raether W, Seidenath H, Mehlhorn H, Ganster HJ. The action of salinomycin-Na and lasalocid-Na on chloroquine- and mepacrine-resistant line of Plasmodium berghei K 173-strain in Wistar rats. ZEITSCHRIFT FUR PARASITENKUNDE (BERLIN, GERMANY) 1985; 71:567-74. [PMID: 3901567 DOI: 10.1007/bf00925589] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
Salinomycin-Na and lasalocid-Na, two ionophorous antibiotics known for their anticoccidial activity, exhibit in vivo blood schizontocidal action on the Plasmodium berghei Keyberg 173 RC/M line that has a high level of resistance to chloroquine and mepacrine. Salinomycin was found to have a greater effect than lasalocid on asexual stages of this line. Trophozoites and schizonts were no longer found after a single dose of 20 mg/kg or five doses of 1.25 mg/kg of salinomycin whereas a single dose of 40 mg/kg or five doses of 20 mg/kg of lasalocid showed no marked effect on parasitaemia within 96 h of starting treatment in rats. Some toxicological data show that lasalocid, however, is better tolerated in domestic animals than salinomycin. Early morphological changes in asexual blood stages were membrane-coiling in the cytoplasm followed by vacuolization and disruption of the cell membrane or pellicle after treatment with both compounds. In particular mature schizonts were totally destroyed showing enormously large vacuoles. Toxicological data and blood schizontocidal activity indicate the narrow safety margin in P. berghei infected rats, and place salinomycin in the 'markedly toxic' group of antimalarial compounds.
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31
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Mehlhorn H, Ortmann-Falkenstein G, Haberkorn A. The effects of sym. Triazinones on developmental stages of Eimeria tenella, E. maxima and E. acervulina: a light and electron microscopical study. ZEITSCHRIFT FUR PARASITENKUNDE (BERLIN, GERMANY) 1984; 70:173-82. [PMID: 6720030 DOI: 10.1007/bf00942219] [Citation(s) in RCA: 55] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
The development of three chicken coccidia (Eimeria tenella, E. acervulina and E. maxima) was studied by means of light and electron microscopy. One group of chickens infected with 6000-20,000 oocysts received a single dose of 5 mg/kg body weight (comparable to approx. 25 ppm in the feed) Bay Vg 7183 or Bay Vi 9142 orally (on day 3 or 4 p.i.), whereas others received two doses (on days 3 and 4 or on days 4 and 5 p.i.). The animals were killed on days 3, 4, 5, 6 and 7 p.i. and parts of the mucosa were dissected from the caecum (E. tenella), the ileum (E. maxima) and the duodenum (E. acervulina). Significant damage was observed in comparison to the controls, affecting nearly all of the parasites in those animals that had been treated twice, whereas some of the parasites remained microscopically unchanged after only one treatment. In general, the perinuclear space, mitochondria and the endoplasmic reticulum were found to be considerably enlarged. Nuclear divisions were disturbed in schizonts and microgamonts, thus resulting in a greatly reduced production of parasites. The most important damage occurring in the macrogamonts concerned the wall-forming bodies II. As they burst, the formation of intact oocyst-walls was hindered, even if fertilization had taken place.
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