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1.
Anim Reprod Sci ; 237: 106922, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35065462

RESUMO

Semen quality is one of the criteria used for the selection of bulls with relatively greater fertility. In addition, bull fertility depends on the integrity and function of all sperm structures. The aim of this study, therefore, was to determine associations when there was conducting of conventional and functional techniques for the evaluation of sperm samples from bulls with known fertility history as determined when semen from these bulls was used for fixed-time artificial insemination programs. The study was designed in a 2 × 2 factorial arrangement, with one factor being breed (Angus x Nellore) and the other fertility (greater x lesser). Greater fertility groups were composed of ten Angus and 11 Nellore bulls, while lesser fertility groups were composed of ten Angus and seven Nellore bulls. Sperm were analyzed, in four cryopreserved distinct batches for each animal, for morphology, kinetics, plasma and acrosomal membrane integrity, mitochondrial activity and mitochondrial membrane potential, DNA integrity and oxidative status. There was no difference in characteristics commonly used in sperm quality conventional analysis. The results from functional analysis indicated an important association between mitochondrial dysfunctions, oxidative stress, and damage to sperm structures in lesser fertility bulls. Greater fertility bulls had greater sperm quality and indicators of functional cell structures. The associations, when there were evaluations using different techniques, indicate the importance of evaluation and correlation between different sperm functions to understand effects of distinct parameters on sperm fertilization capacity.


Assuntos
Análise do Sêmen , Sêmen , Animais , Bovinos , Fertilidade , Inseminação Artificial/métodos , Inseminação Artificial/veterinária , Masculino , Estresse Oxidativo , Sêmen/fisiologia , Análise do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides/fisiologia
2.
Anim Reprod Sci ; 225: 106668, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33341529

RESUMO

The aim of the present study was to evaluate the reproductive status of Bos taurus and Bos indicus bulls during different seasons when bulls were in a tropical environment focusing on systematic assessment of the testes using B-mode ultrasonography and ImageJ software to evaluate the testicular parenchymal tissues. The experimental design is a 2 × 2 factorial arrangement, with breed (Bos Taurus - Simmental; Bos indicus - Nellore) and season (summer; winter) as factors. Testicular ultrasonic evaluation and conventional semen analysis were performed. The Simmental bulls had more major sperm defects than Nellore bulls in the summer (P = 0.0001). Additionally, Simmental bulls had a greater percentage of major sperm defects during the summer than winter months P = 0.045). Furthermore, Nellore bulls had a greater testicular parenchyma echogenicity, with a greater grayscale, (caudal parenchyma, P = 0.0155; cranial parenchyma, P = 0.001) and mediastinum grayscale than Simmental bulls (Nellore = 52.32 ± 03.60; Simmental = 35.72 ± 03.67; P = 0.003). Simmental bulls also had a greater testicular lesion area (P = 0.0147). Results indicated there was susceptibility to heat stress when Simmental bulls were maintained in tropical regions. The results of the present study indicate there is an association between results when there was use of conventional andrological evaluation procedures and results from ultrasonic analysis using ImageJ software that allows for earlier identification of tissue aberrations that could lead to impaired semen quality and fertility.


Assuntos
Bovinos , Testículo/diagnóstico por imagem , Clima Tropical , Ultrassonografia/veterinária , Animais , Masculino , Estações do Ano , Análise do Sêmen/veterinária , Motilidade dos Espermatozoides , Espermatozoides/fisiologia , Testículo/anatomia & histologia
3.
Animals (Basel) ; 10(11)2020 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-33142944

RESUMO

Cystic endometrial hyperplasia-pyometra complex is a canine endometrial disorder, considered the most common and important among uterine diseases. The treatment of choice is ovariohysterectomy, but medical treatments have become an alternative. However, no studies have been performed in order to evaluate uterine hemodynamic changes during medical treatment for pyometra bitches. Therefore, the aim of this study was to compare the effectiveness of two medical protocols by means of clinical (heart rate, respiratory rate and body temperature), medullar response (complete blood count (CBC)) and uterine hemodynamic evaluation in pyometra bitches. For such purpose, 10 bitches with pyometra were assigned to two groups: Aglepristone Group (n = 5) and Associative Group (aglepristone + prostaglandin; n = 5). The Associative Group had altered respiratory rate and decreased body temperature. The Aglepristone Group had decreased plasma protein, however, leukocyte count reduced over time for both therapeutic protocols. Uterine area and vascularization score decreased throughout treatment. There was a significant reduction in uterine perimeter, area and vascularization score. The Associative Group had lower final diastolic velocity and higher systole:diastole ratio (S/D), pulsatility index (PI) and resistance index (RI). In conclusion, both medical treatments are effective in reversing clinical and CBC changes of pyometra, especially aglepristone, however they cannot fully restore local uterine changes in a short-term evaluation. Conversely, associative therapy was more effective in decreasing uterine vascularization and modulating uterine blood flow.

4.
Anim Reprod Sci ; 221: 106585, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32889408

RESUMO

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 ±â€¯0.193 mL, motility - 19.8 ±â€¯18.6 %, vigor - 1.9 ±â€¯1.0, concentration - 40.5 ±â€¯25.2 × 106 sperm/mL and morphologically normal sperm - 10.8 ±â€¯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.


Assuntos
Genitália Masculina/anatomia & histologia , Herpestidae/fisiologia , Análise do Sêmen/veterinária , Espermatozoides/fisiologia , Animais , Animais de Zoológico , Herpestidae/anatomia & histologia , Masculino
6.
Oxid Med Cell Longev ; 2017: 1502489, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29209446

RESUMO

High oxygen levels during in vitro culture (IVC) can induce oxidative stress through accumulation of reactive oxygen species (ROS), negatively affecting embryo development. This study evaluated the effect of different O2 tensions during IVC on bovine blastocyst development and transcriptional status, considering transcription factors that play an essential role during early embryo development. For this purpose, embryos were produced in vitro by conventional protocols and cultured in two different oxygen tensions, physiological (5%) and atmospheric (20%). Expanded blastocysts were subjected to transcript quantitation analysis by RT-qPCR with Biomark™ HD System (Fluidigm, US), using 67 TaqMan assays specific for Bos taurus. Differences were observed in genes related to oxidation-reduction processes, DNA-dependent transcription factors, and factors related to important functional pathways for embryo development. Blastocyst rate was higher in the 5% O2 group and the number of cells was assessed, with the 5% O2 group having a higher number of cells. ROS concentration was evaluated, with a higher ROS presence in the 20% O2 group. Taken together, these results allow us to conclude that IVC of embryos at atmospheric O2 tension affects the expression of important transcription factors involved in multiple cell biology pathways that can affect embryo development, quality, and viability.


Assuntos
Embrião de Mamíferos/metabolismo , Estresse Oxidativo , Fatores de Transcrição/metabolismo , Animais , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Blastocisto/citologia , Blastocisto/metabolismo , Fator de Transcrição CDX2/metabolismo , Bovinos , Embrião de Mamíferos/citologia , Desenvolvimento Embrionário/efeitos dos fármacos , Feminino , Fertilização in vitro , Microscopia de Fluorescência , Oócitos/citologia , Fatores de Transcrição Otx/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Oxigênio/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Transcriptoma/efeitos dos fármacos
7.
J Biomed Opt ; 21(7): 75002, 2016 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-27385403

RESUMO

The timing of the first embryonic cell divisions may predict the ability of an embryo to establish pregnancy. Similarly, metabolic profiles may be markers of embryonic viability. However, in bovine, data about the metabolomics profile of these embryos are still not available. In the present work, we describe Raman-based metabolomic profiles of culture media of bovine embryos with different developmental kinetics (fast x slow) throughout the in vitro culture. The principal component analysis enabled us to classify embryos with different developmental kinetics since they presented specific spectroscopic profiles for each evaluated time point. We noticed that bands at 1076 cm(−1) (lipids), 1300 cm(−1) (Amide III), and 2719 cm(−1) (DNA nitrogen bases) gave the most relevant spectral features, enabling the separation between fast and slow groups. Bands at 1001 cm(−1) (phenylalanine) and 2892 cm(−1) (methylene group of the polymethylene chain) presented specific patterns related to embryonic stage and can be considered as biomarkers of embryonic development by Raman spectroscopy. The culture media analysis by Raman spectroscopy proved to be a simple and sensitive technique that can be applied with high efficiency to characterize the profiles of in vitro produced bovine embryos with different development kinetics and different stages of development.


Assuntos
Bovinos , Metaboloma , Análise Espectral Raman , Animais , Blastocisto , Meios de Cultura , Técnicas de Cultura Embrionária , Embrião de Mamíferos , Desenvolvimento Embrionário , Feminino , Técnicas In Vitro , Gravidez
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