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Dos Santos RP, Silva AR. Sperm Cooling as an Assisted Reproduction Tool for Wildlife: An Underrated Technology. Biopreserv Biobank 2023; 21:388-396. [PMID: 35856795 DOI: 10.1089/bio.2022.0025] [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] [Indexed: 11/12/2022] Open
Abstract
The search for assisted reproduction techniques applied to the conservation and even the genetic improvement of wild species is becoming increasingly common. Regarding conservation of male gametes from wild animals, although current advances are focused on cryopreservation, the development of protocols for sperm refrigeration seems to be underrated, despite its various advantages and applications. Therefore, this review aims to highlight the importance of short-term conservation of sperm from wild mammals, report the development of state-of-the-art refrigeration protocols for both ejaculated and epididymal sperm, and evaluate the challenges and prospects of their application.
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Affiliation(s)
- Romário Parente Dos Santos
- Laboratory for Animal Germplasm Conservation, Department of Animal Sciences, Federal University of the Semiarid Region, Mossoró, Brazil
| | - Alexandre Rodrigues Silva
- Laboratory for Animal Germplasm Conservation, Department of Animal Sciences, Federal University of the Semiarid Region, Mossoró, Brazil
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2
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Moreira SSJ, Lago AEDA, Moura AAA, Silva AR. Impact of Seminal Plasma Composition on Sperm Freezability in Wild Mammals: A Review. Biopreserv Biobank 2021; 20:90-96. [PMID: 34726507 DOI: 10.1089/bio.2021.0026] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
This review was designed to summarize the most important information around seminal plasma composition and discuss its impact on the freezability of wild mammal semen samples. Seminal plasma is made up of various biochemical constituents, including ions, lipids, proteins, enzymes, and sugars, which vary between species in response to the presence and size of any relevant accessory glands. The biochemical constituents of seminal plasma may change as a result of age, individual variability, and seasonality. These constituents are responsible for supporting different functions in sperm cells, contributing to motility, acrosomal reaction, and fertilization events. A detailed understanding of seminal plasma biochemistry may help to optimize semen freezing protocols, enabling the dynamic alteration in diluents to allow for increased sperm viability rates after thawing.
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Affiliation(s)
- Samara Sandy Jerônimo Moreira
- Laboratory for Animal Germplasm Conservation, Department of Animal Sciences, Federal University of the Semiarid Region, Mossoró, Brazil
| | - Arthur Emannuel de Araújo Lago
- Laboratory for Animal Germplasm Conservation, Department of Animal Sciences, Federal University of the Semiarid Region, Mossoró, Brazil
| | | | - Alexandre Rodrigues Silva
- Laboratory for Animal Germplasm Conservation, Department of Animal Sciences, Federal University of the Semiarid Region, Mossoró, Brazil
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3
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Vieira RLA, Feliciano MAR, Moreira RHR, Costa CM. Seminal characterization of white-lipped peccary (Tayassu peccary). Reprod Domest Anim 2021; 57:80-85. [PMID: 34699664 DOI: 10.1111/rda.14031] [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: 07/26/2021] [Accepted: 10/18/2021] [Indexed: 11/26/2022]
Abstract
White-lipped peccary (Tayassu pecari) is a neotropical mammal that plays a fundamental role in maintaining the integrity of tropical forest systems. However, due to hunting and deforestation the species is currently classified as vulnerable. As there are reports of difficulties in captive reproduction, it was proposed to use assisted reproduction techniques for later reintroduction into their natural habitat. Therefore, the objective was to describe the physical, chemical, morphological and functional characteristics of its semen. Sixteen adult male, white-lipped peccary, aged between three and seven years old, distributed in three groups, were used in this study. After physical and chemical retainment, semen was collected by electroejaculation from 16 individuals. It was evaluated by computer analysis (CASA). The mean values recorded were as follows: volume 0.5 ± 0.6 ml, pH 7.2 ± 0.3, sperm concentration 967.2 ± 947.3 × 106 spermatozoon/ml and total motility of 75.4 ± 16.2. The average sperm reactive to the hypo-osmotic test was 85.3% ± 21.0%, and 62.4% ± 43.9% of the cells presented intact membranes in the structural integrity test. Additionally, the semen showed milky consistency (80%), yellowish colour (40%) and sui generis odour (100%). The sperm parameters of the white-lipped peccary are within the desirable standards, allowing them to be considered as potentially fertile for the development of assisted reproduction techniques that may contribute to the conservation of the species.
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Affiliation(s)
| | - Marcus Antônio Rossi Feliciano
- School of Veterinary Medicine and Animal Science, Federal University of Bahia (UFBA), Salvador, Brazil.,Department of Large Animals Clinic, Federal University of Santa Maria (UFSM), Santa Maria, Brazil
| | | | - Cristiana Morais Costa
- School of Veterinary Medicine and Animal Science, Federal University of Bahia (UFBA), Salvador, Brazil
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Mendonça MAC, Nichi M, Teixeira RHF, Braga FR, Simões R, Losano JDDA, Jorge-Neto PN, Pizzutto CS. Spermatic profile of captive giant anteaters (Myrmecophaga tridactyla): Knowing more to preserve better. Zoo Biol 2021; 40:227-237. [PMID: 33739560 DOI: 10.1002/zoo.21602] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2020] [Revised: 10/18/2020] [Accepted: 02/16/2021] [Indexed: 11/06/2022]
Abstract
The giant anteater (Myrmecophaga tridactyla) is being threatened by natural habitat destruction and fragmentation, illegal hunting and road kills. In this context, the generation of basic information on the reproductive parameters of this species is vital, aiming to improve reproductive management via, amongst others, assisted reproductive technologies. This study aimed to describe the morphological and functional features of semen collected from captive giant anteaters. Electroejaculation was performed in 13 animals housed in zoos located in São Paulo state, Brazil. Semen samples were collected from 13 animals in 16 procedures. Samples were evaluated for volume, motility, vigor, pH, concentration, sperm morphology, and functional tests. The following mean values were obtained: volume 1.28 ± 0.27 mL; motility 28.3 ± 6.2%; vigor 2.4 ± 0.25; concentration 129.4 ± 36.1 × 106 sperm/mL; pH 7.4 ± 0.2. Total acrosome, head, midpiece, and tail sperm abnormalities were 3.2 ± 0.8%, 25.4 ± 3.6%, 20.7 ± 3.2%, and 14.7 ± 2.6%, respectively. Intact acrosome was found in 83.7 ± 3.1% and intact membrane in 81.1 ± 4.0% of all samples collected. Mitochondrial activity was 66.4 ± 6.0% (Class I), 18.7 ± 2.9% (Class II), 8.0 ± 2.0% (Class III), 3.9 ± 1.0% (Class IV), and 3.0 ± 0.9% (Class V). Sperm DNA fragmentation rate was 13.2 ± 3.7%. These results indicated that electroejaculation is a feasible method for semen collection in giant anteaters, allowing a more detailed description of the semen in this species.
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Affiliation(s)
- Marco Antonio Carstens Mendonça
- Department of Animal Reproduction, School of Veterinary Medicine and Animal Science, University of São Paulo (USP), São Paulo, SP, Brazil
| | - Marcílio Nichi
- Department of Animal Reproduction, School of Veterinary Medicine and Animal Science, University of São Paulo (USP), São Paulo, SP, Brazil
| | | | - Fabrício Rassy Braga
- Veterinary Division, Fundação Parque Zoológico de São Paulo, SP, São Paulo, Brazil
| | - Renata Simões
- Center for Natural and Human Sciences, Federal University of ABC, Santo André, SP, Brazil
| | - João Diego de Agostini Losano
- Department of Animal Reproduction, School of Veterinary Medicine and Animal Science, University of São Paulo (USP), São Paulo, SP, Brazil
| | - Pedro Nacib Jorge-Neto
- Department of Animal Reproduction, School of Veterinary Medicine and Animal Science, University of São Paulo (USP), São Paulo, SP, Brazil.,Research Division, Instituto Reprocon, Campo Grande, MS, Brazil
| | - Cristiane Schilbach Pizzutto
- Department of Animal Reproduction, School of Veterinary Medicine and Animal Science, University of São Paulo (USP), São Paulo, SP, Brazil.,Research Division, Instituto Reprocon, Campo Grande, MS, Brazil
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Silvatti B, Granato TM, Jorge-Neto PN, Luppi MMCP, Reisfeld LC, Henrique PC, Padilha FLA, Leite RF, Losano JDDA, Kawai GKV, Nichi M, Pizzutto CS. Sperm evaluation and morphological description of male genitalia of meerkats (Suricata suricatta). Anim Reprod Sci 2020; 221:106585. [PMID: 32889408 DOI: 10.1016/j.anireprosci.2020.106585] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 08/20/2020] [Accepted: 08/21/2020] [Indexed: 02/06/2023]
Abstract
In ex situ conditions, little is known about the reproductive biology of meerkats. The aim of present study was to describe the morphological aspects of male genital organs and accessory glands using macroscopic evaluation, ultrasonography, and radiography, as well as describing semen characteristics post-electroejaculation. The results indicated anatomical characteristics of meerkats are very similar to those of cats, having a prostate, accessory bulbourethral glands, and an elongated and radiopaque structure in the penis, which is indicative of there being a baculum. The testicular volume was 0.81 cm³ (± 0.10) and the relative testis weight was 1.37 cm³/kg (± 0.15). Both testicles are present in the scrotum, which has an ellipsoidal shape, homogeneous texture, hypoechoic parenchyma and are encased in a hyperechoic tunica albuginea. Electroejaculation was effectively induced in all animals for semen collection with utilization of medetomidine and ketamine. The values semen samples variables were as follows for volume - 0.125 ± 0.193 mL, motility - 19.8 ± 18.6 %, vigor - 1.9 ± 1.0, concentration - 40.5 ± 25.2 × 106 sperm/mL and morphologically normal sperm - 10.8 ± 6.6 %. This is the first study in which there is a description of morphological and imaging aspects of the male reproductive tracts of meerkats, as well as the seminal characteristics after using electroejaculation for semen collection. Knowledge of anatomical and seminal characteristics is essential for implementation of assisted reproduction programs, as well as reproductive management in the species.
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Affiliation(s)
- Bruna Silvatti
- Department of Animal Reproduction, Faculty of Veterinary Medicine and Husbandry, University of São Paulo, São Paulo, SP, Brazil.
| | | | - Pedro Nacib Jorge-Neto
- Department of Animal Reproduction, Faculty of Veterinary Medicine and Husbandry, University of São Paulo, São Paulo, SP, Brazil
| | | | | | | | | | - Roberta Ferreira Leite
- Department of Animal Reproduction, Faculty of Veterinary Medicine and Husbandry, University of São Paulo, São Paulo, SP, Brazil
| | - João Diego de Agostini Losano
- Department of Animal Reproduction, Faculty of Veterinary Medicine and Husbandry, University of São Paulo, São Paulo, SP, Brazil
| | - Giulia Kiyomi Vechiato Kawai
- Department of Animal Reproduction, Faculty of Veterinary Medicine and Husbandry, University of São Paulo, São Paulo, SP, Brazil
| | - Marcilio Nichi
- Department of Animal Reproduction, Faculty of Veterinary Medicine and Husbandry, University of São Paulo, São Paulo, SP, Brazil
| | - Cristiane Schilbach Pizzutto
- Department of Animal Reproduction, Faculty of Veterinary Medicine and Husbandry, University of São Paulo, São Paulo, SP, Brazil
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Andrews CJ, Thomas DG, Welch MV, Yapura J, Potter MA. Monitoring ovarian function and detecting pregnancy in felids: A review. Theriogenology 2020; 157:245-253. [PMID: 32818882 DOI: 10.1016/j.theriogenology.2020.06.036] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2020] [Revised: 06/14/2020] [Accepted: 06/27/2020] [Indexed: 01/16/2023]
Abstract
Reliable detection and monitoring of estrus and pregnancy is essential to the effective ex situ conservation of endangered felids. Here, we review the current methods used to detect estrus and pregnancy in felids and describe the advantages and limitations of each. A total of 194 felid-focused publications were reviewed. The methods used included behavioral assessments (61 publications across 24 species), hormone monitoring (124 studies across 28 species), fecal protein monitoring (two studies in cheetah), ultrasonography (31 publications across seven species), vaginal cytology (22 publications across nine species), and laparoscopy (70 publications across 19 species). Behavior-based assessments of reproductive state are often inconsistent and unreliable in felids; thus hormone measurement is the most frequently used method for monitoring estrous cycles (66% of studies). In non-domestic felids, non-invasive fecal- or urine-based hormone metabolite analyses are preferred to blood assessments (66% of endocrine-based publications). While the measurement of fecal estrogen and progestin metabolites are useful for the retrospective assessment of ovarian activity, their use for real-time detection of estrus is limited. Vaginal cytology, laparoscopy and ultrasonography provide an acute and immediate determination of reproductive state but usually require anesthesia or sedation, which can prevent ovulation and cause abortions; thus, their use for pregnancy diagnosis is limited. Fecal progesterone or prostaglandin F2α metabolites can be used to detect pregnancy in most felids (the exception being fecal progestins for Lynx spp.), but only during mid-to-late gestation. Urinary relaxin measurement is a promising method for earlier pregnancy diagnosis (30-40% duration of gestation) but is presently limited by poor assay sensitivity due to the lack of a feline-specific relaxin antibody. Elevated levels of fecal immunoglobulin J chain have been investigated as a tool to detect pregnancy in cheetah (>80% accuracy), but research is lacking on other species. We conclude that there is no single 'best method' for monitoring ovarian activity and detecting pregnancy in felids, and current best practice would involve a combination of existing methods. Non-invasive methods for detecting estrus and pregnancy in felids (e.g., accelerometry and infrared thermography) should also be considered to augment existing methods.
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Affiliation(s)
- Christopher J Andrews
- Animal Science Group, School of Agriculture and Environment, Massey University, Private Bag 11-222, Palmerston North, 4442, New Zealand.
| | - David G Thomas
- Animal Science Group, School of Agriculture and Environment, Massey University, Private Bag 11-222, Palmerston North, 4442, New Zealand.
| | - Marcia V Welch
- Wildlife and Ecology Group, School of Agriculture and Environment, Massey University, Private Bag 11-222, Palmerston North, 4442, New Zealand.
| | - Jimena Yapura
- School of Veterinary Science, Massey University, Private Bag 11-222, Palmerston North, 4442, New Zealand.
| | - Murray A Potter
- Wildlife and Ecology Group, School of Agriculture and Environment, Massey University, Private Bag 11-222, Palmerston North, 4442, New Zealand.
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Araujo GRD, Deco-Souza TD, Bergo LCF, Silva LCD, Morato RG, Jorge-Neto PN, Silva MCCD, Macedo GG, Paula TARD. Field friendly method for wild feline semen cryopreservation. JOURNAL OF THREATENED TAXA 2020. [DOI: 10.11609/jott.5744.12.5.15557-15564] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
The aim of this study was to develop a field-friendly method for free-living jaguar and cougar semen cryopreservation. Six captive Jaguars Panthera onca and three captive Cougars Puma concolor were chemically restrained with a combination of medetomidine (0.08–0.1 mg/kg) and ketamine (5 mg/kg). Semen was collected through a tomcat urinary catheter with an open end, diluted for a final concentration of 50 x 106 sperm/mL in a TRIS-egg yolk extender and packaged into 0.25 mL straws. We compared two cooling methods: CoolA - in which straws were placed in a glass tube that was placed in a glass bottle containing water (600mL at 38°C) and transferred to a polystyrene container (12L) containing an 11cm column of ice and water at room temperature; CoolB – where the glass bottle – straws kit was transferred to a 4.26L cooler containing nine blocks (81cm3) of Ice Foam recyclable ice, previously frozen in liquid nitrogen. The sperm volume varied from 2 to 720 µl for the jaguars and from 80 to 140 µl for the cougars. Sperm concentration varied from 224 to 5,115 x106 sperm/mL for the jaguars and from 485.7 to 562.5 x 106 sperm/mL for the cougars. Concerning the cooling treatments, there was no difference in frozen-thawed sperm quality between the methods, in both species. Thereby, the cooling method using recyclable ice frozen in liquid nitrogen can be used for semen cryopreservation in wild felines, eliminating the need for electric energy.
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Silva HVR, Nunes TGP, Ribeiro LR, Freitas LAD, de Oliveira MF, Assis Neto ACD, Silva AR, Silva LDMD. Morphology, morphometry, ultrastructure, and mitochondrial activity of jaguar (Panthera onca) sperm. Anim Reprod Sci 2019; 203:84-93. [DOI: 10.1016/j.anireprosci.2019.02.011] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2018] [Revised: 01/11/2019] [Accepted: 02/25/2019] [Indexed: 12/23/2022]
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Silva HVR, Silva AR, da Silvada LDM, Comizzoli P. Semen Cryopreservation and Banking for the Conservation of Neotropical Carnivores. Biopreserv Biobank 2018; 17:183-188. [PMID: 30589562 DOI: 10.1089/bio.2018.0104] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Neotropical carnivores include a large number of threatened and endangered species. It is critical to develop conservation efforts to ensure the sustainability of populations in situ and ex situ. The highest priorities are to protect natural habitats and better understand the biology of rare species. Conservation efforts also are directed toward the implementation of breeding programs and the development of reproductive biotechnologies in which the cryopreservation of male gametes plays a major role. It also is fundamental to create semen banks that contribute to maintaining genetic diversity in small and endangered populations. The present article aims at reviewing the state of the art in cryopreservation of semen from neotropical carnivores and discuss the development of systematic banking for the conservation of these understudied species.
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Affiliation(s)
| | | | | | - Pierre Comizzoli
- 3 Smithsonian Conservation Biology Institute, Washington, District of Columbia
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10
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Praxedes ÉCG, Peixoto GCX, Maria da Silva A, Silva AR. Reproduction in agouti (Dasyprocta spp . ): A review of reproductive physiology for developing assisted reproductive techniques. Anim Reprod 2018; 15:1181-1192. [PMID: 34221130 PMCID: PMC8203115 DOI: 10.21451/1984-3143-ar2018-0058] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Dasyprocta spp. (agouti) include wild rodents with highlighted ecological
and economic importance, and are considered experimental models for endangered hystricognath
rodents. Of late, development of techniques to conserve their genetic material as well as
the formation of biobanks is increasing. In this context, this review describes the main advances
in the knowledge of the reproductive morphophysiological specificities of agouti as well
as the development and improvement of assisted reproductive techniques aimed at conservation,
multiplication, and exploitation of their reproductive potential under captivity.
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Affiliation(s)
- Érica Camila Gurgel Praxedes
- Laboratory on Animal Germplasm Conservation, Universidade Federal Rural do Semi Árido (UFERSA), BR 110, Km 47, Costa and Silva, Mossoró, RN, Brazil
| | - Gislayne Christianne Xavier Peixoto
- Laboratory on Animal Germplasm Conservation, Universidade Federal Rural do Semi Árido (UFERSA), BR 110, Km 47, Costa and Silva, Mossoró, RN, Brazil
| | - Andréia Maria da Silva
- Laboratory on Animal Germplasm Conservation, Universidade Federal Rural do Semi Árido (UFERSA), BR 110, Km 47, Costa and Silva, Mossoró, RN, Brazil
| | - Alexandre Rodrigues Silva
- Laboratory on Animal Germplasm Conservation, Universidade Federal Rural do Semi Árido (UFERSA), BR 110, Km 47, Costa and Silva, Mossoró, RN, Brazil
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Sousa P, Amorim R, Lima G, Paiva A, Paula V, Freitas C, Silva A. Establishment of an anesthetic protocol for semen collection by electroejaculation in six-banded armadillos (Euphractus sexcinctus Linnaeus, 1758). ARQ BRAS MED VET ZOO 2016. [DOI: 10.1590/1678-4162-8811] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
ABSTRACT The aim was to verify the effects of different anesthetic protocols used during electroejaculation (EEJ) in six-banded armadillos (Euphractus sexcinctus). Four sexually matured animals were physically restrained and subjected to semen collection by the EEJ following three treatments: The control group consisted of no use of anesthesia; in the others, the anesthetic combinations xylazine/ketamine/propofol or butorphanol/ ketamine/propofol were administered. For each group, twelve procedures were conducted for EEJ. Semen was evaluated for volume, color, aspect, motility, sperm concentration, morphology, viability, and functional membrane integrity. The highest efficiency (100% ejaculates) was achieved when the control group was used; the xylazine/ketamine/propofol association provided only 11 ejaculates from a total of 12 attempts (91.6% efficiency), while only 4 ejaculates (33% efficiency) were obtained with butorphanol/ketamine/propofol (P<0.05). Both protocols provided rapid induction and relaxation enough to perform the EEJ. In the use of butorphanol/ketamine/propofol, the animals recovered at 16.5±1.5min, a time shorter than in the use of xylazine/ketamine/propofol protocol, 20.7±1.0min (P>0.05). The semen volume and sperm concentration obtained in the use of xylazine/ketamine/propofol association were significantly higher than those verified for butorphanol/ketamine/propofol protocol. In conclusion, the xylazine/ketamine/propofol association is indicated for anesthesia of six-banded armadillos submitted to EEJ.
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Affiliation(s)
- P.C. Sousa
- Universidade Federal Rural do Semiárido, Brazil
| | | | - G.L. Lima
- Universidade Federal Rural do Semiárido, Brazil
| | | | - V.V. Paula
- Universidade Federal Rural do Semiárido, Brazil
| | | | - A.R. Silva
- Universidade Federal Rural do Semiárido, Brazil
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12
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Silva HVR, Magalhães FF, Ribeiro LR, Souza ALP, Freitas CIA, de Oliveira MF, Silva AR, Silva LDM. Morphometry, Morphology and Ultrastructure of Ring-tailed Coati Sperm ( Nasua nasuaLinnaeus, 1766). Reprod Domest Anim 2015; 50:945-51. [DOI: 10.1111/rda.12613] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 08/26/2015] [Indexed: 11/29/2022]
Affiliation(s)
- HVR Silva
- Laboratory of Carnivores Reproduction; State University of Ceará; Fortaleza CE Brazil
| | - FF Magalhães
- Laboratory of Carnivores Reproduction; State University of Ceará; Fortaleza CE Brazil
| | - LR Ribeiro
- Aba-Yby Conservation Institute; EcoPoint; Fortaleza CE Brazil
| | - ALP Souza
- Laboratory of Animal Germplasm Conservation; Federal Rural University of Semi-Arid; Mossoró RN Brazil
| | - CIA Freitas
- Multiplication Center of Wild Animals; Federal Rural University of Semi-Arid; Mossoró RN Brazil
| | - MF de Oliveira
- Animal Science Department; Federal Rural University of Semi-Arid; Mossoró RN Brazil
| | - AR Silva
- Laboratory of Animal Germplasm Conservation; Federal Rural University of Semi-Arid; Mossoró RN Brazil
| | - LDM Silva
- Laboratory of Carnivores Reproduction; State University of Ceará; Fortaleza CE Brazil
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Castelo TS, Souza ALP, Lima GL, Peixoto GCX, Campos LB, Oliveira MF, Silva AR. Interactions Among Different Devices and Electrical Stimulus on the Electroejaculation of Captive Agoutis (Dasyprocta leporina). Reprod Domest Anim 2015; 50:492-6. [PMID: 25800458 DOI: 10.1111/rda.12517] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/30/2014] [Accepted: 02/28/2015] [Indexed: 11/28/2022]
Abstract
The interactions among different electroejaculation devices associated with serial or continuous stimuli were investigated to improve the efficiency of the electroejaculation for semen collection in agoutis. Ten sexually matured male Dasyprocta leporina were restrained by the intramuscular administration of xylazine-ketamine association. Each individual was randomly subjected to four electroejaculation protocols, by combining two devices (one presenting longitudinal electrodes emitting square waves and other presenting ring electrodes emitting sine waves) and two electrical stimuli protocols (serial or continuous). A total of 40 attempts for electroejaculation were conducted in agoutis, being 10 per treatment. The most efficient treatment in providing ejaculates containing sperm (p < 0.05) was that using and electroejaculator connected to a probe with ring electrodes and associated with serial stimuli (4/7; 57%). In spite of semen parameters obtained by sine waves were adequate for using the samples for assisted reproduction, higher values for sperm motility and functional membrane integrity were obtained in the use of the square wave, independently of the electric stimulation protocol used (p < 0.05). In conclusion, we verified that the use of a device presenting a probe with ring electrodes and emitting sine waves, associated with a serial stimuli protocol, improves the efficiency for semen obtaining by electroejaculation in adults D. leporina.
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Affiliation(s)
- T S Castelo
- Laboratory of Animal Germplasm Conservation - LCGA, Universidade Federal Rural do Semi-Árido - UFERSA, Mossoró, RN, Brazil
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Rao BS, Mahesh YU, Suman K, Charan KV, Nath R, Rao KR. Meiotic maturation of oocytes recovered from the ovaries of Indian big cats at postmortem. In Vitro Cell Dev Biol Anim 2014; 51:19-25. [DOI: 10.1007/s11626-014-9802-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2014] [Accepted: 07/22/2014] [Indexed: 10/24/2022]
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15
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de Paiva ALC, Nunes TL, de Oliveira MGC, de Morais AML, Dos Santos EAA, Silva AR, de Oliveira MF, de Paula VV. Effects of atipamezole and medetomidine administration on seminal variables and functions of erection and ejaculation of the collared peccary (Tayassu tajacu) after electroejaculation. BMC Vet Res 2014; 10:170. [PMID: 25103781 PMCID: PMC4236823 DOI: 10.1186/s12917-014-0170-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Accepted: 07/21/2014] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Alpha adrenergic drugs are usually used in the treatment of erectile and ejaculatory dysfunction in humans. The influence of such drugs on the seminal characteristics of wild animals has not been verified; whereas their impact on the seminal characteristics and erectile and ejaculatory functions of collared peccaries (Tayassu tajacu) has already been determined. This study aimed at investigating and comparing the effects of medetomidine and atipamezole on the seminal variables of collared peccaries undergoing electroejaculation as well as at determining whether these drugs affected the erectile and ejaculatory functions of this species. RESULTS A statistically significant difference in sperm concentration was observed between AP (100.0 ± 26.0 × 106 sperm/ml) and MP (220.2 ± 49.8 × 106 sperm/ml); however, both these treatments did not differ from P treatment (180.0 ± 50.7 × 106 sperm/ml). No statistically significant difference was observed among all treatments with regard to erectile function. With regard to ejaculation time, no significant difference was observed between the MP and AP treatments; however, when compared with the P treatment, AP exhibited a significantly higher difference. CONCLUSIONS When collared peccaries were anesthetized with propofol, neither medetomidine nor atipamezole significantly affected the characteristics of the semen or the erectile function, despite the fact that the AP treatment increased ejaculation time. Therefore, the data indicate that using propofol alone is an effective anesthetic protocol for collecting semen in collared peccaries. Other non-injectable anesthetic drugs, such as inhaled anesthetics, may be used in future research to collect semen from peccaries.
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Affiliation(s)
- Ariana L C de Paiva
- Laboratory of Anesthesiology and Animal Surgery, Universidade Federal Rural do Semi-Árido, Mossoró, RN, Brazil.
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Reproduction and Advances in Reproductive Studies in Carnivores. ADVANCES IN EXPERIMENTAL MEDICINE AND BIOLOGY 2014; 753:205-39. [DOI: 10.1007/978-1-4939-0820-2_10] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
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Snedaker AK, Honaramooz A, Dobrinski I. A Game of Cat and Mouse: Xenografting of Testis Tissue From Domestic Kittens Results in Complete Cat Spermatogenesis in a Mouse Host. ACTA ACUST UNITED AC 2013; 25:926-30. [PMID: 15477365 DOI: 10.1002/j.1939-4640.2004.tb03163.x] [Citation(s) in RCA: 94] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Loss of genetic diversity because of infertility or the premature death of valuable individuals is a significant problem in the conservation of rare and endangered felid species, as well as in the maintenance of lines of cats used to study inherited feline and human disease. Attempts to overcome loss of genetic diversity have focused on freezing sperm; however, sperm cannot be collected from immature males. Previously, we reported completion of spermatogenesis in testis tissue from newborn pigs and goats grafted ectopically into host mice. The objective of this study was to extend the technique of testis tissue xenografting to the domestic cat as a model for felid species. Testes from 1- to 5-week-old domestic shorthaired kittens (n = 9) were cut into small fragments (about 0.5-1 mm3 each), and up to 8 fragments were grafted under the back skin of each castrated immunodeficient host mouse (n = 16). Histologic examination of the testis xenografts was performed between 5 and 54 weeks posttransplantation. At the time of grafting, the seminiferous cords of the donor testis tissue contained only immature Sertoli cells and gonocytes. At 14 weeks after grafting, tubular expansion was evidently caused by the proliferation of Sertoli cells and tubular lumen formation. By 18 weeks after transplantation, the seminiferous epithelium contained spermatocytes, and by 20 weeks, round spermatids were the most advanced types of germ cells. By 36 weeks after transplantation, xenografts of cat testis tissue had completed spermatogenesis. These results demonstrate the potential of xenografting to achieve full spermatogenesis in testis tissue from kittens. Therefore, sperm production in a mouse host can provide an alternative for germ line preservation from immature felids where sperm cryopreservation is not an option.
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Affiliation(s)
- Amy K Snedaker
- Center for Animal Transgenesis and Germ Cell Research, Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, 382 West Street Road, Kennett Square, PA 19348, USA
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Influence of the thawing rate on the cryopreservation of semen from collared peccaries (Tayassu tajacu) using Tris-based extenders. Theriogenology 2010; 74:1060-5. [DOI: 10.1016/j.theriogenology.2010.05.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2009] [Revised: 05/03/2010] [Accepted: 05/05/2010] [Indexed: 11/19/2022]
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Lima G, Costa L, Cavalcanti D, Rodrigues C, Freire F, Fontenele-Neto J, Silva A. Short-term storage of canine preantral ovarian follicles using a powdered coconut water (ACP®)-based medium. Theriogenology 2010; 74:146-52. [DOI: 10.1016/j.theriogenology.2010.01.025] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2009] [Revised: 01/18/2010] [Accepted: 01/30/2010] [Indexed: 11/16/2022]
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20
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Serafim M, Lira R, Costa L, Gadelha I, Freitas C, Silva A. Description of semen characteristics from six-banded armadillos (Euphractus sexcinctus) collected by electroejaculation. Anim Reprod Sci 2010; 118:362-5. [DOI: 10.1016/j.anireprosci.2009.08.012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2009] [Revised: 07/21/2009] [Accepted: 08/18/2009] [Indexed: 10/20/2022]
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Queiroz JPAF, Barros FFPC, Lima GL, Castelo TS, Freitas CIA, Silva AR. Assessment of Orchidometry and Scrotal Circumference in Coatis (Nasua nasua). Reprod Domest Anim 2010; 45:e382-6. [DOI: 10.1111/j.1439-0531.2010.01582.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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22
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Effect of storage of domestic cat (Felis catus) epididymides at 5°C on sperm quality and cryopreservation. Theriogenology 2009; 72:1268-77. [DOI: 10.1016/j.theriogenology.2009.07.023] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2009] [Revised: 07/27/2009] [Accepted: 07/29/2009] [Indexed: 11/17/2022]
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Souza A, Castelo T, Queiroz J, Barros I, Paula V, Oliveira M, Silva A. Evaluation of anesthetic protocol for the collection of semen from captive collared peccaries (Tayassu tajacu) by electroejaculation. Anim Reprod Sci 2009; 116:370-5. [DOI: 10.1016/j.anireprosci.2009.02.017] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2009] [Revised: 02/19/2009] [Accepted: 02/27/2009] [Indexed: 10/21/2022]
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Determination of semen characteristics and sperm cell ultrastructure of captive coatis (Nasua nasua) collected by electroejaculation. Anim Reprod Sci 2009; 115:225-30. [DOI: 10.1016/j.anireprosci.2008.11.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2008] [Revised: 10/18/2008] [Accepted: 11/04/2008] [Indexed: 11/21/2022]
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Barros F, Queiroz J, Filho A, Santos E, Paula V, Freitas C, Silva A. Use of two anesthetic combinations for semen collection by electroejaculation from captive coatis (Nasua nasua). Theriogenology 2009; 71:1261-6. [DOI: 10.1016/j.theriogenology.2009.01.003] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2008] [Revised: 01/04/2009] [Accepted: 01/05/2009] [Indexed: 11/26/2022]
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Siemieniuch MJ, Woclawek-Potocka I. Assessment of Selected Quality Parameters of Epididymal Cat (Felis catuss.domestica,L. 1758) Sperm Using Flow Cytometry Method and Computer Assisted Sperm Analyser. Reprod Domest Anim 2008; 43:633-7. [DOI: 10.1111/j.1439-0531.2007.00958.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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Pelican KM, Wildt DE, Ottinger MA, Howard J. Priming with progestin, but not GnRH antagonist, induces a consistent endocrine response to exogenous gonadotropins in induced and spontaneously ovulating cats. Domest Anim Endocrinol 2008; 34:160-75. [PMID: 17369001 DOI: 10.1016/j.domaniend.2007.01.002] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/05/2006] [Revised: 01/15/2007] [Accepted: 01/30/2007] [Indexed: 11/16/2022]
Abstract
Ovarian sensitivity to exogenous gonadotropin stimulation (equine chorionic gonadotropin [eCG] and human chorionic gonadotropin [hCG]) following pre-treatment with a progestin (levonorgestrel) versus GnRH antagonist (antide) was studied in cats known to be induced versus spontaneous ovulators. Queens were assigned to one of three treatments: (1) levonorgestrel implants+eCG/hCG (n=7 cats); (2) antide injections+eCG/hCG (n=7) or (3) eCG/hCG alone (control; n=7). Hormonal metabolites were assessed in fecal samples collected daily for 60 days before and during the 37 days inhibitory pre-treatment and for more than 60 days after eCG/hCG. Fecal metabolites of estradiol and progesterone were measured by radioimmunoassay. Females that maintained baseline progesterone were considered induced ovulators, whereas cats that exhibited a luteal phase before inhibition treatment were classified as spontaneous ovulators. Based on fecal hormone profiles, levonorgestrel thoroughly inhibited ovarian activity, whereas antide synchronized follicular phases but did not induce complete ovarian down-regulation. Both treatments prevented ovulation in spontaneous ovulators, but neither caused regression of existing corpora lutea (CL). Levonorgestrel, but not antide, pre-treatment resulted in a quiescent ovary at the time of eCG injection, yet endocrine responses to eCG/hCG were not different among treatments. Interestingly, spontaneously ovulating females exhibited a prolonged estradiol response to gonadotropin stimulation compared to induced ovulators, and this prolonged estradiol surge was replicated by levonorgestrel pre-treatment. Thus, the progestin levonorgestrel effectively suppresses follicular and luteal activity in the cat, resulting in a more consistent response to gonadotropin stimulation, even in females prone to spontaneous ovulation.
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Affiliation(s)
- Katharine M Pelican
- Conservation & Research Center, Smithsonian's National Zoological Park, Front Royal, VA 22630, United States.
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Hanna C, Menges S, Kraemer D, Long CR. Synchronisation of canine germinal vesicle stage oocytes prior to in vitro maturation alters the kinetics of nuclear progression during subsequent resumption of meiosis. Reprod Fertil Dev 2008; 20:606-14. [DOI: 10.1071/rd07227] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2007] [Accepted: 04/07/2008] [Indexed: 11/23/2022] Open
Abstract
Inhibition of meiosis before in vitro maturation (IVM) can improve meiotic competence in immature mammalian oocytes. Therefore, meiosis-inhibiting agents were evaluated singularly for the ability to arrest and synchronise germinal vesicle (GV) stage canine oocytes, and the most effective treatments were combined to improve meiotic resumption rates. Oocytes cultured in 2 ng mL–1 oestradiol (E2), 10 IU mL–1 eCG, or both (EG) for 72 h resulted in significantly fewer oocytes resuming meiosis in EG than the control, E2, or with eCG. Oocytes cultured in 50 or 100 μmol L–1 of butyrolactone 1 or roscovitine (ROS) for up to 48 h did not resume meiosis nor increase subsequent meiotic resumption rates following IVM. A combination of 50 μmol L–1 ROS and EG treatment for 48 h significantly increased the proportion of canine oocytes in meiotic arrest. More importantly, following 48 h of IVM, ROS+EG-treated oocytes demonstrated a dramatic increase in the ability to resume meiosis compared with the non-treated controls (51.3 ± 8.2% and 10.8 ± 4.5%, respectively; P < 0.05). These data indicate that chemical and biological meiotic inhibitors are effective at inducing GV arrest in canine oocytes. Furthermore, these inhibitors are reversible and beneficial to subsequent meiotic resumption in vitro.
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Johnston SD, Ward D, Lemon J, Gunn I, MacCallum CA, Keeley T, Blyde D. Studies of male reproduction in captive African wild dogs (Lycaon pictus). Anim Reprod Sci 2007; 100:338-55. [PMID: 16987622 DOI: 10.1016/j.anireprosci.2006.08.017] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2006] [Revised: 08/03/2006] [Accepted: 08/07/2006] [Indexed: 10/24/2022]
Abstract
Implementation of assisted breeding in the captive African wild dog is restricted by a current lack of knowledge on their reproductive physiology and the apparent difficulty of effectively manipulating the complex social dynamic of the pack in order to conduct reproductive procedures. In this study, we describe protocols for the safe and repeated capture and restraint of the African wild dog (n=7) as well as techniques for assessment of male reproductive function, semen collection and preservation. In a serendipitous finding, captive African wild dogs appeared to display significant seasonal change in male reproduction. Testicular volume and tone, spermatorrhea and the ability to collect semen by electroejaculation all increased significantly during late summer and then subsequently declined by early spring. While there were no detectable seasonal changes in testosterone concentration in the population as whole, the alpha-dominant male in both years of the study, had a highly elevated testosterone concentration compared to subordinate males. Semen collection by electroejaculation during the late summer was most effective in peri-pubertal males (15 months) when all seven electroejaculates were of adequate quality for cryopreservation. In the second breeding season (27 months), there were numerous changes in the pack hierarchy and electroejaculation was not as successful (3/7). The characteristics of electroejaculated semen collected in the breeding season are described for seven animals including the first descriptions and incidence of sperm abnormalities in the species. Semen (n=7) was frozen using a Tris-citrate fructose buffer and final egg yolk and glycerol concentration of 20% and 4%, respectively. Sperm were loaded into 0.25 mL straws, frozen in liquid nitrogen vapor and then thawed at 37 degrees C. Initial post-thaw survival of spermatozoa was encouraging (% motile: 31.8+/-5.8%; rate: 2.8+/-0.3; % intact plasma membranes: 33.4+/-5.3% and the % of damaged acrosomes: 4.4+/-1.5%) but following 2 h incubation at 37 degrees C, post-thaw survival declined markedly.
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Affiliation(s)
- S D Johnston
- School of Animal Studies, The University of Queensland, Gatton 4343, Australia.
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Pesch S, Bergmann M. Structure of mammalian spermatozoa in respect to viability, fertility and cryopreservation. Micron 2006; 37:597-612. [PMID: 16621580 DOI: 10.1016/j.micron.2006.02.006] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2005] [Accepted: 02/28/2006] [Indexed: 11/25/2022]
Abstract
Morphological assessment of spermatozoa has a long history and it is generally accepted that specific morphologic structural deviations correlate with male sub- and infertility. Although many different and also new methods are used in semen analysis, light microscopy is still used for routine morphological evaluation. This paper gives an overview about the detailed structure of physiological mammalian spermatozoa as well as the most common morphological deviations in correlation to fertility. This should be the basis for explanation of problems resulting from semen cryopreservation. General aspects of semen cryopreservation should be regarded before to facilitate the understanding of methods and mechanisms.
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Affiliation(s)
- Sandra Pesch
- Clinic for Obstetrics, Gynecology and Andrology of Large and Small Animals, Justus-Liebig-University, Frankfurter Str. 106, 35392 Giessen, Germany.
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Abstract
Appreciable progress has been made in the development of assisted reproductive technology (ART) for creating in vitro embryos in cats. Moreover, the extent of advancement in the last decade has been similar, albeit of more modest magnitude, to that seen in some other domestic and laboratory species, particularly when the disparities in financial, and, hence, scientific, resources are considered. The recent progress in domestic felid ART has made it possible to envisage their potential role in supporting the conservation of endangered felid species, which, in reality, is a multifarious process requiring wide-ranging, yet coordinated approaches. The prospect of incorporating ART into that intricate domain, with limited exceptions, remains a long-term, but highly motivating objective. Meanwhile, the straightforward accessibility and abundant supply of domestic cat gametes from local veterinary clinics provides a valuable and practical source of material for further research on the basic aspects of in vitro oocyte maturation, fertilization and early embryo development. Furthermore, extrapolating the domestic biotechniques to non-domestic felids has produced encouraging results in some species.
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Affiliation(s)
- C E Pope
- Audubon Nature Institute Center for Research of Endangered Species, New Orleans, LA 70131, USA.
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Silva A, Cardoso R, Silva L. Comparison between different dilution rates on canine semen freezing using Tris-buffer with the addition of egg-yolk and glycerol. ARQ BRAS MED VET ZOO 2005. [DOI: 10.1590/s0102-09352005000600010] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Standardized sperm concentration and volume:volume extension were compared as dilution rates for canine semen freezing. Six proven stud dogs were submitted to two seminal collections by manual stimulation. Semen was evaluated and extended in tris plus egg-yolk and glycerol according to two different dilution rates. The first one was based on a standardized sperm concentration of 200x10(6) spermatozoa/ml and the second was a volume:volume extension at a proportion of one part semen to one part extender. Semen was frozen, stored in liquid nitrogen and thawed after one week. Sperm motility and vigor were appraised after each stage of the process and at 15 and 30min post-thawing. Sperm morphology was analyzed after collection and thawing. No differences were observed between treatments after thawing regarding sperm motility and vigor, normal sperm morphology rate or longevity. Both dilution rates can be efficiently used for canine semen freezing.
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