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1.
Animals (Basel) ; 13(21)2023 Oct 25.
Artículo en Inglés | MEDLINE | ID: mdl-37958070

RESUMEN

This study presents the first successful capture using GPS tagging of a jaguar (Panthera onca) using a minimally invasive capture system (MICS). We used snare-foot traps and a MICS during two capture campaigns in a fragment of Atlantic Forest in southeastern Brazil. The specimen disarmed snares on different occasions, and capture was only possible with the MICS. The captured jaguar, an estimated 16-year-old adult male, was monitored using a GPS Vertex Plus Iridium collar with an optimal performance of 86% in expected locations. The jaguar's home range (659 km2 by MPC and 174 km2 by 95%K) was within the observed range for the species and the animal was primarily maintained in protected areas. The habitat types most frequently used were native grassland (27.2% of 4798 fixes), marsh (24.8%), and dense lowland forest (24.7%). The use of a MICS for trapping jaguars is a promising technique that shows advantages in terms of efficiency, selectivity, portability, reduced potential risk of injury to animals or trappers, and animal stress compared to other capture methods used for the species.

2.
Anim Reprod Sci ; 163: 56-62, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26526118

RESUMEN

We evaluated the capacity of ocelot and oncilla spermatozoa to bind to the perivitelline membranes (PVMs) of hen eggs in a sperm binding assay (S-PVM). In addition, a device that improves the standardization of the assay was developed. The number of sperm bound to the PVM in fresh (T1) and frozen-thawed (T2) semen from both species was compared to the sperm quality observed in routine tests. The PVM was stretched on a circular silicone device to create a standardized area for analysis. In both treatments and for both species, the spermatozoa were able to bind to the PVM, indicating that PVM may be used for a sperm binding assay in ocelot and oncilla. The S-PVM assay did not differ in fresh and frozen-thawed ocelot sperm (p>0.05). However, fewer oncilla sperm (p<0.05) were bound to the PVM in T2, indicating that the proposed test may be able to detect injuries that compromise sperm binding abilities. The device maintained the PVM stretched during the processing and defined the evaluation area.


Asunto(s)
Felidae/fisiología , Espermatozoides/fisiología , Membrana Vitelina/fisiología , Animales , Pollos , Criopreservación/veterinaria , Masculino , Preservación de Semen/veterinaria , Interacciones Espermatozoide-Óvulo/fisiología , Espermatozoides/metabolismo
4.
Microsc Res Tech ; 76(1): 94-101, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23077089

RESUMEN

Environmental factors can influence the reproductive rates in bats, and since morphometric information of bats testis is scarce, we aimed to compare the organization and quantification of the intertubular components in the testes of the bat Molossus molossus, collected in different seasons. Testicular histological sections were evaluated using light and electron microscopy. The intertubular compartment occupied an average 10% of the testes, being predominately constituted of Leydig cells (LC). The percentages of the testes occupied by the intertubular compartment and by LC were significantly higher in summer, while the other intertubular components did not vary significantly among the seasons. As suspected under light microscopy, the ultrastructural analysis confirmed the existence of multinucleated LC during winter. The increase in the nuclear percentage of LC in winter seems to have caused the decrease of the cytoplasmatic measurements in that season, as well as in the volume of LC. The highest cytoplasmatic values and volume of LC registered in the spring, summer, and fall can be related to greater activity of this cell in these seasons. The higher investment in intertubular tissue and in LC observed in summer, compared to winter; suggest an increase in the steroidogenic capacity of this bat during summer. The analyses correlating testicular morphometry and abiotic environmental factors in this study confirm the influence of climatic factors on the reproduction of M. molossus.


Asunto(s)
Quirópteros/anatomía & histología , Túbulos Seminíferos/ultraestructura , Animales , Quirópteros/fisiología , Células Intersticiales del Testículo/ultraestructura , Masculino , Microscopía Electrónica , Tamaño de los Órganos , Reproducción , Estaciones del Año , Túbulos Seminíferos/crecimiento & desarrollo , Testículo/crecimiento & desarrollo , Testículo/ultraestructura
5.
Theriogenology ; 77(5): 873-80, 2012 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-22153265

RESUMEN

Six adult Leopardus tigrinus (oncilla) were studied to characterize stages of the seminiferous epithelium cycle and its relative frequency and duration, as well as morphometric parameters of the testes. Testicular fragments were obtained (incisional biopsy), embedded (glycol methacrylate), and histologic sections examined with light microscopy. The cycle of the seminiferous epithelium was categorized into eight stages (based on the tubular morphology method). The duration of one seminiferous epithelium cycle was 9.19 d, and approximately 41.37 d were required for development of sperm from spermatogonia. On average, diameter of the seminiferous tubules was 228.29 µm, epithelium height was 78.86 µm, and there were 16.99 m of testicular tubules per gram of testis. Body weight averaged 2.589 kg, of which 0.06 and 0.04% were attributed to the testis and seminiferous tubules, respectively. In conclusion, there were eight distinct stages in the seminiferous epithelium, the length of the seminiferous epithelium cycle was close to that in domestic cats and cougars, and testicular and somatic indexes were similar to those of other carnivores of similar size.


Asunto(s)
Felidae/anatomía & histología , Felidae/fisiología , Epitelio Seminífero/citología , Epitelio Seminífero/fisiología , Animales , Peso Corporal , Brasil , Masculino , Tamaño de los Órganos , Túbulos Seminíferos/anatomía & histología , Túbulos Seminíferos/fisiología , Células de Sertoli/ultraestructura , Espermátides/ultraestructura , Espermatocitos/ultraestructura , Espermatogénesis , Espermatogonias/ultraestructura , Espermatozoides/ultraestructura , Testículo/anatomía & histología , Testículo/química
6.
Anim Reprod Sci ; 127(3-4): 202-12, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21889273

RESUMEN

Information on the reproductive biology of neotropical cervids is scarce. Therefore, the aim of this study was to perform biometric, histologic and stereologic analyses of the brown brocket deer Mazama gouazoubira testis, with an emphasis on the intrinsic yield and the Sertoli cell index. Seven adult males kept in captivity were used. The animals were immobilized; anesthetized and testicle fragments were obtained by biopsy incision. The material was fixed, processed and examined by routine histological methods for light microscopy. The average body weight was 17.2kg, from which 0.40% were allocated in gonads and 0.33% in seminiferous tubules, which represented 85.9% of the testis parenchyma. The mean albuginea width and volume were 345.7µm and 3.5mL (5.3% of the testicular weight), respectively. The mean mediastinum volume of both testicles was 1.0mL (1.5% of the testicular weight) and the testicular parenchyma volume corresponded to 93.1% of total testicular weight (64.9g). The seminiferous tubules diameter was 224.4µm, while the epithelium height was 69.6µm. On average, an adult brown brocket deer showed a total of 1418m of seminiferous tubules in both testicles (21.5m per gram of testis). Each stage I seminiferous tubular cross section contained 1.10 type A spermatogonia, 13.4 primary spermatocytes in pre-leptotene/leptotene, 13.7 spermatocytes in pachytene, 48.8 round spermatids and 3.7 Sertoli cells. The general yield of spermatogenesis was 44.7 cells and the Sertoli cell index was 13.2. The qualitative and quantitative description of testicular histology of brown brocket deer help to understand its spermatogenic process and to establish parameters for the reproductive biology of this wild species. Furthermore, the data from the present research will help further studies using other species of Brazilian cervids, especially endangered ones, making an additional effort to the species preservation.


Asunto(s)
Ciervos/anatomía & histología , Recuento de Espermatozoides , Testículo/anatomía & histología , Testículo/citología , Animales , Recuento de Células , Color , Masculino , Células de Sertoli/citología , Recuento de Espermatozoides/veterinaria , Recuperación de la Esperma , Espermátides/citología , Espermatocitos/citología , Espermatogénesis/fisiología , Espermatogonias/citología , Testículo/ultraestructura , Clima Tropical
7.
Anim Reprod Sci ; 118(1): 83-8, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19564086

RESUMEN

The intrinsic yield of spermatogenesis and supporting capacity of Sertoli cells are the desirable indicators of sperm production in a species. The objective of the present study was to quantify intrinsic yield and the Sertoli cell index in the spermatogenic process and estimate testicular sperm reserves by histological assessment of fragments obtained by testicular biopsy of five adult jaguars in captivity. The testicular fragments were fixed in 4% glutaric aldehyde, dehydrated at increasing alcohol concentrations, included into hydroxyethyl methacrylate, and were cut into 4 microm thickness. In the seminiferous epithelium of the jaguar, 9.2 primary spermatocytes in pre-leptotene were produced by "A" spermatogonia. During the meiotic divisions only 3.2 spermatids were produced by a primary spermatocyte. The general spermatogenic yield of the jaguar was about 23.4 cells and each Sertoli cell was able to maintain about 19.2 germ cells, 11 of them were round spermatids. In each seminiferous epithelium cycle about 166 million spermatozoa were produced by each gram of testicular tissue. In adult jaguars, the general spermatogenic yield was similar to the yield observed in pumas, greater than that observed for the domestic cat, but less compared to most domestic animals.


Asunto(s)
Indicadores de Salud , Panthera/fisiología , Espermatogénesis/fisiología , Espermatozoides/citología , Testículo/citología , Animales , Recuento de Células/veterinaria , Eficiencia , Masculino , Células de Sertoli/citología , Recuperación de la Esperma/veterinaria , Espermátides/citología , Espermatocitos/citología , Espermatozoides/fisiología , Testículo/fisiología
8.
Anim Reprod Sci ; 102(3-4): 350-6, 2007 12.
Artículo en Inglés | MEDLINE | ID: mdl-17499460

RESUMEN

The intrinsic yield of spermatogenesis and the supporting indexes of the Sertoli cells are the best indicators for the spermatic production capacity in a species. The aim of the present study was to quantify the intrinsic yield of the spermatogenetic process, as well as the Sertoli cell index and spermatic reserves. Testicular fragments of five adult African lions was fixed in 4% glutaric aldehyde, dehydrated at increasing alcohol concentrations, included into hydroxyethyl methacrylate, and were cut into 4 microm thickness. In the seminiferous epithelium of the African lions, 10.3 primary spermatocytes at pre-leptotene phase are produced by the type-A spermatogonia. During meiotic divisions, only 2.7 spermatids were produced from the primary spermatocytes. The general spermatogenesis production in the African lions was approximately 22.1 cells, and each Sertoli cell was able to sustain and maintain approximately 14.9 cells of the germinative line, from which 7.9 are round spermatids. A total of 103x10(6) spermatozoa are produced by each testis gram at each cycle of the seminiferous epithelium. The spermatic reserve of lion is below the amplitude observed in mammals.


Asunto(s)
Animales de Zoológico/fisiología , Leones/fisiología , Células de Sertoli/fisiología , Recuento de Espermatozoides , Espermatogénesis/fisiología , Animales , Masculino , Epitelio Seminífero/citología , Espermátides/citología , Espermatocitos/citología , Espermatogonias/citología , Testículo/citología
9.
Micron ; 38(6): 584-9, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17157026

RESUMEN

The duration of the seminiferous epithelium cycle was estimated in adult maned wolves (Chrysocyon brachyurus, Illiger, 1811), by applying intratesticular injections with tritiated thymidine. The total duration of the seminiferous epithelium cycle in this species was calculated in 8.99 days. So, taking into account that approximately 4.5 cycles of the seminiferous epithelium are necessary for the whole spermatogenesis process to complete, the production of spermatozoa from one spermatogonia will take about 40.45 days. The duration of the spermiogenesis was calculated to be 12.3 days. The eight stages of the seminiferous epithelium cycle were described by the tubular morphology method, which is based either on the form and position of the spermatid nuclei and the occurrence of meiotic divisions. The values of the relative frequency for the pre-meiotic, meiotic and post-meiotic phases in this species were 3.5, 0.78 and 4.8 days, respectively. The maned wolf produces about 29 million spermatozoa a day for each testis gram, therefore being classified among the species provided with a high spermatogenetic efficiency.


Asunto(s)
Canidae/fisiología , Epitelio Seminífero/fisiología , Espermatogénesis/fisiología , Animales , Masculino , Microscopía/métodos , Epitelio Seminífero/ultraestructura , Células de Sertoli/fisiología , Células de Sertoli/ultraestructura , Espermátides/fisiología , Espermátides/ultraestructura , Espermatocitos/fisiología , Espermatocitos/ultraestructura , Espermatogonias/fisiología , Espermatogonias/ultraestructura , Espermatozoides/fisiología , Espermatozoides/ultraestructura , Testículo/fisiología
10.
Anim Reprod Sci ; 91(3-4): 307-16, 2006 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15923093

RESUMEN

Puma or sussuarana (Puma concolor) is the second largest feline in the American continent and has an ample latitudinal distribution in very diverse habitats. In relation to its conservation status, the puma is considered an extinction-threatened species. The study of the testis morphology and the spermatogenic process in a species is fundamental for establishing the physiologic patterns that will make possible the selection of the protocols for assisted reproduction. A number of peculiarities associated with the reproductive biology of specific species such as the duration of spermatogenic process can be used to determine the frequency of sperm collection. Nine adult male pumas maintained in captivity were used to determine the relative frequency of stages in the seminiferous epithelium cycle. Three of them received intra-testicular injections of 0.1ml tritiated thymidine to determine the duration of the seminiferous epithelium cycle, and were subjected to biopsy 7 days later. The cycle of the seminiferous epithelium in puma was didactically described into eight stages by the tubular morphology method. The total duration of one seminiferous epithelium cycle in puma was calculated to be 9.89 days, and approximately 44.5 days are required for development of spermatozoon from spermatogonia. The duration of spermiogenesis, prophase and other events of meiosis were 14.08, 15.20 and 1.79 days, respectively. The relative frequency of the pre-meiotic, meiotic and post-meiotic phases were 3.98, 1.79 and 4.12 days, respectively.


Asunto(s)
Puma , Epitelio Seminífero/ultraestructura , Animales , Nucléolo Celular/ultraestructura , Núcleo Celular/ultraestructura , Masculino , Meiosis , Epitelio Seminífero/fisiología , Células de Sertoli/ultraestructura , Espermátides/ultraestructura , Espermatocitos/ultraestructura , Espermatogonias/ultraestructura , Factores de Tiempo
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