1
|
Ďuračka M, Benko F, Chňapek M, Tvrdá E. Strategies for Bacterial Eradication from Human and Animal Semen Samples: Current Options and Future Alternatives. SENSORS (BASEL, SWITZERLAND) 2023; 23:6978. [PMID: 37571761 PMCID: PMC10422635 DOI: 10.3390/s23156978] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/30/2023] [Revised: 08/02/2023] [Accepted: 08/04/2023] [Indexed: 08/13/2023]
Abstract
The primary role of semen processing and preservation is to maintain a high proportion of structurally and functionally competent and mature spermatozoa, that may be used for the purposes of artificial reproduction when needed, whilst minimizing any potential causes of sperm deterioration during ex vivo semen handling. Out of a multitude of variables determining the success of sperm preservation, bacterial contamination has been acknowledged with an increased interest because of its often unpredictable and complex effects on semen quality. Whilst antibiotics are usually the most straight-forward option to prevent the bacterial contamination of semen, antimicrobial resistance has become a serious threat requiring widespread attention. As such, besides discussing the consequences of bacteriospermia on the sperm vitality and the risks of antibiotic overuse in andrology, this paper summarizes the currently available evidence on alternative strategies to prevent bacterial contamination of semen prior to, during, and following sperm processing, selection, and preservation. Alternative antibacterial supplements are reviewed, and emphasis is given to modern methods of sperm selection that may be combined by the physical removal of bacteria prior to sperm preservation or by use in assisted reproductive technologies.
Collapse
Affiliation(s)
- Michal Ďuračka
- AgroBioTech Research Centre, Slovak University of Agriculture in Nitra, Tr. A. Hlinku 2, 949 76 Nitra, Slovakia
| | - Filip Benko
- Institute of Applied Biology, Faculty of Biotechnology and Food Sciences, Slovak University of Agriculture in Nitra, Tr. A. Hlinku 2, 949 76 Nitra, Slovakia
- Institute of Biotechnology, Faculty of Biotechnology and Food Sciences, Slovak University of Agriculture in Nitra, Tr. A. Hlinku 2, 949 76 Nitra, Slovakia
| | - Milan Chňapek
- Institute of Biotechnology, Faculty of Biotechnology and Food Sciences, Slovak University of Agriculture in Nitra, Tr. A. Hlinku 2, 949 76 Nitra, Slovakia
| | - Eva Tvrdá
- Institute of Biotechnology, Faculty of Biotechnology and Food Sciences, Slovak University of Agriculture in Nitra, Tr. A. Hlinku 2, 949 76 Nitra, Slovakia
| |
Collapse
|
2
|
Montes-Garrido R, Riesco MF, Anel-Lopez L, Neila-Montero M, Palacin-Martinez C, Boixo JC, de Paz P, Ortega-Ferrusola C, Hassan MAA, Anel L, Alvarez M. Application of ultrasound technique to evaluate the testicular function and its correlation to the sperm quality after different collection frequency in rams. Front Vet Sci 2022; 9:1035036. [PMID: 36504850 PMCID: PMC9732105 DOI: 10.3389/fvets.2022.1035036] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Accepted: 11/11/2022] [Indexed: 11/27/2022] Open
Abstract
The frequency of semen collection is a crucial factor to consider in the rams performance inside breeding centers workout. To evaluate this factor, ram Breeding Soundness Evaluation could include sperm quality evaluation and new predictive and non-invasive tools such as ultrasound technique. In this work, an advanced ultrasonography technology, analyzing the testicular volume, echotexture, and vascular function, was used in three different frequencies of semen collection (abstinence frequency, AF; standard frequency, SF; and intensive frequency, IF). Semen samples were cooled (15°C, 6 h) and evaluated in terms of production, motility, viability, apoptosis, and content of reactive oxygen species. Correlation coefficients were calculated between ultrasonography measurements of echotexture and blood flow and sperm quality parameters. Our results showed an increase in the testicular echotexture when the frequency of semen collection was intensified. Doppler parameters (PSV, RI, PI, TABF) increased (P ≤ 0.05) when the frequency of semen collection was intensified. The sperm motility and functionality decreased in the samples of IF (P ≤ 0.05), evidencing the frequency of semen collection's influence. Moreover, moderate positive correlations were established among echotexture and different Doppler parameters with motility parameters in SF. Furthermore, the influence of abstinence days on AI success was analyzed in a field assay. The highest fertility rates were obtained when males had two to five abstinence days. To conclude, frequency of semen collection could be influenced in terms of semen quantity and sperm quality, showing changes in parenchyma echotexture and testicular vascularization. The standard semen collection frequency was the most adequate option. In addition, ultrasonography may be a predictive tool for estimating variations in the sperm quality of donor rams subjected to different frequencies of semen collection in reproduction centers.
Collapse
Affiliation(s)
- Rafael Montes-Garrido
- Investigación en Técnicas de Reproducción Asistida – Universidad de León, Instituto de Desarrollo Ganadero y Sanidad Animal, University of León, León, Spain,Animal Reproduction and Obstetrics, Department of Veterinary Medicine, Surgery and Anatomy, University of León, León, Spain
| | - Marta F. Riesco
- Investigación en Técnicas de Reproducción Asistida – Universidad de León, Instituto de Desarrollo Ganadero y Sanidad Animal, University of León, León, Spain,Celular Biology, Department of Molecular Biology, University of León, León, Spain
| | - Luis Anel-Lopez
- Investigación en Técnicas de Reproducción Asistida – Universidad de León, Instituto de Desarrollo Ganadero y Sanidad Animal, University of León, León, Spain,Anatomy, Department of Veterinary Medicine, Surgery and Anatomy, University of León, León, Spain,*Correspondence: Luis Anel-Lopez
| | - Marta Neila-Montero
- Investigación en Técnicas de Reproducción Asistida – Universidad de León, Instituto de Desarrollo Ganadero y Sanidad Animal, University of León, León, Spain,Animal Reproduction and Obstetrics, Department of Veterinary Medicine, Surgery and Anatomy, University of León, León, Spain
| | - Cristina Palacin-Martinez
- Investigación en Técnicas de Reproducción Asistida – Universidad de León, Instituto de Desarrollo Ganadero y Sanidad Animal, University of León, León, Spain,Animal Reproduction and Obstetrics, Department of Veterinary Medicine, Surgery and Anatomy, University of León, León, Spain
| | - Juan Carlos Boixo
- Investigación en Técnicas de Reproducción Asistida – Universidad de León, Instituto de Desarrollo Ganadero y Sanidad Animal, University of León, León, Spain,Animal Reproduction and Obstetrics, Department of Veterinary Medicine, Surgery and Anatomy, University of León, León, Spain
| | - Paulino de Paz
- Investigación en Técnicas de Reproducción Asistida – Universidad de León, Instituto de Desarrollo Ganadero y Sanidad Animal, University of León, León, Spain,Celular Biology, Department of Molecular Biology, University of León, León, Spain
| | - Cristina Ortega-Ferrusola
- Laboratory of Equine Reproduction and Equine Spermatology, Veterinary Teaching Hospital, University of Extremadura, Cáceres, Spain
| | - Mohamed A. A. Hassan
- Department of Anatomy and Embryology, Faculty of Veterinary Medicine, Sohag University, Sohag, Egypt
| | - Luis Anel
- Investigación en Técnicas de Reproducción Asistida – Universidad de León, Instituto de Desarrollo Ganadero y Sanidad Animal, University of León, León, Spain,Animal Reproduction and Obstetrics, Department of Veterinary Medicine, Surgery and Anatomy, University of León, León, Spain
| | - Mercedes Alvarez
- Investigación en Técnicas de Reproducción Asistida – Universidad de León, Instituto de Desarrollo Ganadero y Sanidad Animal, University of León, León, Spain,Animal Reproduction and Obstetrics, Department of Veterinary Medicine, Surgery and Anatomy, University of León, León, Spain
| |
Collapse
|
3
|
Moreira SSJ, Santos CS, Castelo TS, Bezerra LGP, Praxedes ÉCG, Matos TM, Souza-Junior JBF, Feijó FMC, Comizzoli P, Silva AR. Investigating the need for antibiotic supplementation to the extender used for semen cryopreservation in collared peccaries. Front Vet Sci 2022; 9:954921. [PMID: 36118351 PMCID: PMC9478795 DOI: 10.3389/fvets.2022.954921] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2022] [Accepted: 08/18/2022] [Indexed: 11/13/2022] Open
Abstract
The objective was to investigate the effects of semen freezing extender supplementation with antibiotics on bacterial load of semen samples, sperm functional and morphological metrics in the collared peccary. Fresh ejaculates from 10 males were extended in Tris-egg yolk-glycerol supplemented or not (control) with gentamicin (70 μg/mL) streptomycin-penicillin (SP; 1 mg/mL−1000 IU/mL) or and cryopreserved in liquid nitrogen. Bacterial load, sperm motility patterns, morphology, membrane functionality and integrity, mitochondrial activity, chromatin integrity and sperm-binding ability were evaluated in fresh and frozen-thawed samples. Regardless of the use of antibiotics, the sole cryopreservation provoked a significant decrease (P < 0.05) in bacterial load compared to fresh samples (from average values > 1 x 106 CFU/mL to <0.4 × 106 CFU/mL). Post-thawing sperm kinetic parameters were not affected by the absence or presence of different antibiotics, except for beat cross frequency that was significantly (P < 0.05) impaired by SP supplementation compared to the group without antibiotics. After thawing, sperm morphology, membrane functionality and integrity, and mitochondrial activity were also not affected by the presence or absence of antibiotics; however, a significant decrease was observed in the group without antibiotics (P < 0.05) in comparison to fresh samples. Regarding sperm-binding ability, there were no differences among the different groups. While collared peccary semen could be efficiently cryopreserved in the absence of antibiotics in the extender, the use of both gentamicin or the streptomycin-penicillin combination is recommended as effective antibiotic supplementation for a further control of bacterial loads without affecting sperm parameters.
Collapse
Affiliation(s)
- Samara S. J. Moreira
- Laboratory of Animal Germplasm Conservation, Federal Rural University of Semi-Arid (UFERSA), Mossoró, RN, Brazil
| | - Caio S. Santos
- Laboratory of Animal Germplasm Conservation, Federal Rural University of Semi-Arid (UFERSA), Mossoró, RN, Brazil
| | - Thibério S. Castelo
- Laboratory of Animal Germplasm Conservation, Federal Rural University of Semi-Arid (UFERSA), Mossoró, RN, Brazil
| | - Luana G. P. Bezerra
- Laboratory of Animal Germplasm Conservation, Federal Rural University of Semi-Arid (UFERSA), Mossoró, RN, Brazil
| | - Érica C. G. Praxedes
- Laboratory of Animal Germplasm Conservation, Federal Rural University of Semi-Arid (UFERSA), Mossoró, RN, Brazil
| | - Tayná M. Matos
- Laboratory of Animal Germplasm Conservation, Federal Rural University of Semi-Arid (UFERSA), Mossoró, RN, Brazil
| | - João B. F. Souza-Junior
- Laboratory of Animal Germplasm Conservation, Federal Rural University of Semi-Arid (UFERSA), Mossoró, RN, Brazil
| | | | - Pierre Comizzoli
- Smithsonian National Zoo and Conservation Biology Institute, Washington, DC, United States
| | - Alexandre R. Silva
- Laboratory of Animal Germplasm Conservation, Federal Rural University of Semi-Arid (UFERSA), Mossoró, RN, Brazil
- *Correspondence: Alexandre R. Silva
| |
Collapse
|
4
|
Guedea-Betancourt JJ, Quezada-Casasola A, Núñez-Gastélum JA, Orozco-Lucero E, Escárcega-Ávila AM, Soler Valls AJ, Carrera-Chávez JM. Effect of Moringa oleifera seed extract on antimicrobial activity and in vitro fertilization ability of cryopreserved ram semen. Reprod Domest Anim 2022; 57:1564-1571. [PMID: 35997503 DOI: 10.1111/rda.14233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2022] [Revised: 08/16/2022] [Accepted: 08/21/2022] [Indexed: 11/28/2022]
Abstract
Cryopreservation has adverse effects on the post-thaw sperm quality due to oxidative stress and the presence of bacteria. To minimize such effects, plant extracts have been included in the composition of the semen diluents. The objective of the present study was to evaluate the antimicrobial and antioxidant effects of Moringa oleifera seed extract (MOSE) on cryopreserved ram semen, as well as its impact on in vitro fertilization. Semen from six hair rams was treated with five treatments before cryopreservation: Control (without any antibiotic), Standard (conventional antibiotic), 1.0, 10.0, and 50.0 mg/mL of MOSE. Post-thawing sperm characteristics were evaluated by the computer-assisted semen analysis. Antimicrobial activity was assessed by counting colony-forming units (CFU) and the antioxidant capacity by the ferric reducing antioxidant power method. A heterologous in vitro fertilization technique was implemented to measure the fertilization rate. Progressive and rapid motility, membrane and acrosome integrity, and active mitochondria were higher (p < 0.05) in the 10.0 mg/mL treatment compared to Standard after thawing. All M. oleifera treatments showed inhibition of CFU. The antioxidant capacity of M. oleifera seed extract was higher in the 10.0 and 50.0 mg/mL treatments. Fertilization rate (cleavage percentage) was higher (p < 0.05) in the 10.0 mg/mL (82.9±10.0) and Control (82.5±9.9) treatments compared to Standard (73.7±9.1). The addition of 10.0 mg/mL of MOSE to ram semen inhibits the development of microorganisms and improves sperm characteristics and the in vitro fertility of the semen.
Collapse
Affiliation(s)
- José Julián Guedea-Betancourt
- Department of Veterinary Sciences, Institute of Biomedical Sciences, Autonomous University of Ciudad Juárez, Chihuahua, Mexico
| | - Andrés Quezada-Casasola
- Department of Veterinary Sciences, Institute of Biomedical Sciences, Autonomous University of Ciudad Juárez, Chihuahua, Mexico
| | - José Alberto Núñez-Gastélum
- Department of Chemical Biological Sciences, Institute of Biomedical Sciences, Autonomous University of Ciudad Juárez, Chihuahua, Mexico
| | - Ernesto Orozco-Lucero
- Department of Veterinary Sciences, Institute of Biomedical Sciences, Autonomous University of Ciudad Juárez, Chihuahua, Mexico
| | - Angélica María Escárcega-Ávila
- Department of Veterinary Sciences, Institute of Biomedical Sciences, Autonomous University of Ciudad Juárez, Chihuahua, Mexico
| | - Ana Josefa Soler Valls
- Higher Technical School of Agricultural and Forestry Engineers, University of Castilla-La Mancha, Albacete, Spain
| | - José Maria Carrera-Chávez
- Department of Veterinary Sciences, Institute of Biomedical Sciences, Autonomous University of Ciudad Juárez, Chihuahua, Mexico
| |
Collapse
|
5
|
Tvrdá E, Kačániová M, Baláži A, Vašíček J, Vozaf J, Jurčík R, Ďuračka M, Žiarovská J, Kováč J, Chrenek P. The Impact of Bacteriocenoses on Sperm Vitality, Immunological and Oxidative Characteristics of Ram Ejaculates: Does the Breed Play a Role? Animals (Basel) 2021; 12:ani12010054. [PMID: 35011159 PMCID: PMC8749681 DOI: 10.3390/ani12010054] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Revised: 12/19/2021] [Accepted: 12/22/2021] [Indexed: 12/27/2022] Open
Abstract
Bacterial contamination of semen is an often overlooked, yet important, factor contributing to decreased sperm vitality. Understanding the impact of bacterial presence on sperm structural integrity and functional activity may assist the development of effective strategies to prevent, or manage, bacteriospermia in the breeding practice. The aim of this study was to describe the bacterial profiles of ram semen (n = 35), and we also focused on the associations between bacteriospermia, sperm structure, and function, as well as oxidative and inflammatory characteristics of semen. For a better insight, the samples were divided into three groups, according to the breeds used in the study: native Wallachian (NW), improved Wallachian (IW), and Slovak dairy (SD) breeds. The results showed a significantly lower motility and membrane integrity in the NW group in comparison to the IW and SD groups, which was accompanied by a significantly higher concentration of leukocytes, increased reactive oxygen species (ROS) generation, and subsequent oxidative insults to the sperm lipids and proteins. Accordingly, the NW group presented with the highest bacterial load, in which Staphylococcus and Escherichia were the predominant representatives. The Pearson correlation analysis uncovered positive relationships amongst the bacterial load and leukocytospermia (r = 0.613), the extent of lipid peroxidation (r = 0.598), protein oxidation (r = 0.514), and DNA fragmentation (r = 0.638). Furthermore, positive correlations were found between the bacterial load and pro-inflammatory molecules, such as the C-reactive protein (r = 0.592), interleukin 1 (r = 0.709), and interleukin 6 (r = 0.474), indicating a possible involvement of the immune response in the process of bacteriospermia. Overall, our data indicate that ram semen quality may be equally affected by the bacterial load and diversity. Furthermore, we can assume that the presence of bacteria in ejaculates triggers inflammatory processes, causes ROS overproduction, and, thereby, contributes to alterations in the sperm structure, while at the same time compromising the fertilization ability of male gametes.
Collapse
Affiliation(s)
- Eva Tvrdá
- Faculty of Biotechnology and Food Sciences, Slovak University of Agriculture, Tr. A. Hlinku 2, 94976 Nitra, Slovakia; (E.T.); (J.V.); (J.V.); (M.Ď.); (J.K.)
| | - Miroslava Kačániová
- Institute of Horticulture, Faculty of Horticulture and Landscape Engineering, Slovak University of Agriculture, Tr. A. Hlinku 2, 94976 Nitra, Slovakia;
- Department of Bioenergetics, Food Analysis and Microbiology, Institute of Food Technology and Nutrition, University of Rzeszow, Cwiklinskiej 1, 35-601 Rzeszow, Poland
| | - Andrej Baláži
- NPPC, Research Institute for Animal Production Nitra, Hlohovecka 2, 95141 Luzianky, Slovakia; (A.B.); (R.J.)
| | - Jaromír Vašíček
- Faculty of Biotechnology and Food Sciences, Slovak University of Agriculture, Tr. A. Hlinku 2, 94976 Nitra, Slovakia; (E.T.); (J.V.); (J.V.); (M.Ď.); (J.K.)
- NPPC, Research Institute for Animal Production Nitra, Hlohovecka 2, 95141 Luzianky, Slovakia; (A.B.); (R.J.)
| | - Jakub Vozaf
- Faculty of Biotechnology and Food Sciences, Slovak University of Agriculture, Tr. A. Hlinku 2, 94976 Nitra, Slovakia; (E.T.); (J.V.); (J.V.); (M.Ď.); (J.K.)
| | - Rastislav Jurčík
- NPPC, Research Institute for Animal Production Nitra, Hlohovecka 2, 95141 Luzianky, Slovakia; (A.B.); (R.J.)
| | - Michal Ďuračka
- Faculty of Biotechnology and Food Sciences, Slovak University of Agriculture, Tr. A. Hlinku 2, 94976 Nitra, Slovakia; (E.T.); (J.V.); (J.V.); (M.Ď.); (J.K.)
| | - Jana Žiarovská
- Faculty of Agrobiology and Food Resources, Slovak University of Agriculture, Tr. A. Hlinku 2, 94976 Nitra, Slovakia;
| | - Ján Kováč
- Faculty of Biotechnology and Food Sciences, Slovak University of Agriculture, Tr. A. Hlinku 2, 94976 Nitra, Slovakia; (E.T.); (J.V.); (J.V.); (M.Ď.); (J.K.)
| | - Peter Chrenek
- Faculty of Biotechnology and Food Sciences, Slovak University of Agriculture, Tr. A. Hlinku 2, 94976 Nitra, Slovakia; (E.T.); (J.V.); (J.V.); (M.Ď.); (J.K.)
- NPPC, Research Institute for Animal Production Nitra, Hlohovecka 2, 95141 Luzianky, Slovakia; (A.B.); (R.J.)
- Correspondence: ; Tel.: +421-37-654-6285
| |
Collapse
|
6
|
The Efficiency of Selected Extenders against Bacterial Contamination of Boar Semen in a Swine Breeding Facility in Western Slovakia. Animals (Basel) 2021; 11:ani11113320. [PMID: 34828051 PMCID: PMC8614807 DOI: 10.3390/ani11113320] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2021] [Revised: 11/10/2021] [Accepted: 11/17/2021] [Indexed: 12/17/2022] Open
Abstract
Simple Summary This study evaluated the efficiency of selected semen extenders to prevent bacterial overgrowth in boar ejaculates stored for 72 h. Among the identified bacterial isolates, Escherichia coli and Pseudomonas aeruginosa were the most prevailing species. While all extenders supplemented with antibiotics ensured a satisfactory sperm vitality during the storage period, neither of them was able to achieve a complete elimination of bacteria from extended semen. Furthermore, a number of bacterial isolates exhibited resistance to several antibiotics chosen for the microbial susceptibility test (e.g., tigecyklin and ciprofloxacin). Abstract Bacteriospermia has become a serious factor affecting sperm quality in swine breeding, this is why antibiotics (ATBs) are a critical component of semen extenders. Due to ever-increasing antimicrobial resistance, the aim of this study was to assess the efficiency of selected commercially available semen extenders to prevent a possible bacterial contamination of boar ejaculates. Three Androstar Plus extenders containing different combinations of antibiotics were used to process ejaculates from 30 healthy Duroc breeding boars. Androstar Plus without antibiotics was used as a control. The extended samples were stored at 17 °C for 72 h. Sperm motility, viability, mitochondrial activity, DNA integrity and oxidative profile of each extended sample were assessed following 24 h, 48 h and 72 h. Furthermore, selective media were used to quantify the bacterial load and specific bacterial species were identified with matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry. The results indicate that semen extenders enriched with ATBs ensured a significantly higher preservation of the sperm quality in comparison to the ATB-free control. The total bacterial count was significantly decreased in the extenders supplemented with ATBs (p < 0.001), however gentamycin alone was not effective enough against Gram-positive bacteria, while a few colonies of Enterococcus hirae, Bacillus subtilis and Corynebacterium spp. were present in the samples extended in the presence of a triple combination of ATBs. In conclusion, we may suggest that semen extenders enriched in antibiotics were not able to fully eliminate the bacteria present in the studied samples. Furthermore, selection of suitable antibiotics for semen extension should be accompanied by adequate hygiene standards during the collection and handling of boar ejaculates.
Collapse
|
7
|
Antimicrobially Active Semen Extenders Allow the Reduction of Antibiotic Use in Pig Insemination. Antibiotics (Basel) 2021; 10:antibiotics10111319. [PMID: 34827258 PMCID: PMC8615084 DOI: 10.3390/antibiotics10111319] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2021] [Revised: 10/13/2021] [Accepted: 10/25/2021] [Indexed: 12/24/2022] Open
Abstract
Antibiotic use in semen extenders for livestock may contribute to the development and spreading of multi-drug resistance. Antimicrobial control in semen doses for artificial insemination of pigs is indispensable due to the relatively high storage temperature (17 °C). The objectives of this study were first, to examine whether the antimicrobial capacity differs between antibiotic-free extenders and second, to determine whether an antimicrobial active extender provides the possibility to reduce antibiotics. Antibiotic-free semen extenders Beltsville Thawing Solution (BTS) and Androstar Premium were inoculated at 103 to 104 CFU/mL with four pure bacterial strains isolated from boar ejaculates or a mixture thereof, and then stored for 144 h at 17 °C. Bacterial counts after aerobic culture decreased in BTS up to one log level and decreased in Androstar Premium by 2 to 3.5 log levels (p < 0.05). In semen samples from nine boars stored in the inoculated Androstar Premium extender containing half of the standard concentration of gentamicin, bacteria counts were below 101 CFU/mL. Likewise, half of the standard dose of apramycin and ampicillin was fully antimicrobially active and sperm quality was maintained. In conclusion, semen extenders with intrinsic antimicrobial activity allow a reduction in antibiotic use in pig insemination.
Collapse
|