Effects of natural environmental conditions on the ovarian histometric dynamics of five striped squirrels (Funambulus pennanti) / Efectos de las condiciones ambientales naturales sobre la dinámica histométrica de ovarios en la ardilla de las palmeras (Funambulus pennanti)

The present study was designed to determine the morphological and histological variations in the female palm squirrel's reproductive organs which inhabit croplands of central Punjab. 16 specimens were collected from 3 different locations of Faisalabad district during different months in order to collect their ovaries samples in order to determine the breeding phenology of this species. Body weight and external body measurements were recorded. Two adult females were autopsied each month and their ovaries were extracted. Tissue were prepared by the tissue paraffin technique and stained by H&E. Seasonal variations in the follicular size and shape were observed. Statistical analysis revealed that values of all parameters of ovaries were significantly (P<0.01) higher during peak folliculogenic phase (January to May) as compared to low folliculogenic phase (November­December). Three reproductive phases were observed according to follicular development i.e., quiescent period (November- December), recrudescence period (January) and peak reproductive phase (February­March). In conclusion of this study, different phases of sexual activities are determined which are controlled by seasonal variations. These variations are in accordance to different physical factors which influences gross anatomical and histological changes of ovaries and folliculogensis of female five-striped northern palm squirrel (Funambulus pennanti) for adjustments in breeding phenology.

El presente estudio fue diseñado para determinar las variaciones morfológicas e histológicas en los órganos reproductores de la ardilla de las palmeras que habita en las tierras de cultivo del centro de Punjab. Dieciséis muestras fueron recolectadas en 3 lugares diferentes del distrito de Faisalabad durante diferentes meses con el fin de obtener los ovarios y determinar la fenología reproductiva de esta especie. Se registraron el peso corporal y las medidas corporales externas. Se realizaron autopsias de dos hembras adultas cada mes y sus ovarios fueron extraídos. Se prepararon los tejidos por técnica de parafina y tinción H & E y se observaron las variaciones estacionales en el tamaño y forma folicular. El análisis estadístico reveló que los valores de todos los parámetros de los ovarios fueron significativamente más altos durante la fase foliculogénica (enero a mayo), en comparación con la fase baja (noviembre-diciembre) (P <0,01). De acuerdo al desarrollo folicular se observaron tres fases reproductivas, el período de reposo (noviembre-diciembre), el período de recrudecimiento (enero) y la fase peak reproductiva (febrero-marzo). En conclusión las diferentes fases de las actividades sexuales definitivamente están controladas por variaciones estacionales. Estas variaciones se ajustan a diferentes factores físicos que influyen en los cambios anatómicos e histológicos de los ovarios y la folículogénesis de la ardilla hembra de las palmeras (Funambulus pennanti) para realizar ajustes en la fenología de su reproducción.

The liver micromorphology of the african palm squirrel epixerus ebii / Micromorfología del hígado de la ardilla de palma africana epixerus ebii

The normal liver histology of the African palm squirrel Epixerus ebii was investigated to fill the information gap on its micromorphology from available literature. The liver was covered by a capsule of dense connective tissue- the perivascular fibrous capsule. Beneath this capsule is the liver parenchyma were the hepatocyte were supported by reticular fibres. The hepatocytes in the lobules were hexagonal to polygonal in shape. Some hepatocytes were bi-nucleated. Clear spaces in the parenchyma must be storage sites for lipids in the liver. The classic hepatic lobules presented central vein surrounded by several liver cells. At the portal triad, hepatic vein, hepatic arteries and bile ducts were seen. While the hepatic arteries and veins were lined by endothelium, the bile ducts were lined by simple cuboidal cells. Nerve fibres were also seen in the region of the portal triad. Hepatic sinusoids lined by endothelium were seen in the liver parenchyma between liver lobules. The sinusoids contained macrophages. This report will aid wild life biologists in further investigative research and Veterinarians in diagnosing the hepatic diseases of the African palm squirrel.

Describimos la histología hepática normal de la ardilla de palma africana Epixerus ebii para llenar el vacío sobre su micromorfología en la literatura disponible. El hígado está cubierto por una cápsula de tejido conectivo denso, la cápsula fibrosa perivascular. Debajo de esta cápsula se encuentra el parénquima hepático en el cual fibras reticulares apoyan los hepatocitos. Los hepatocitos en los lóbulos son hexagonales de forma poligonal. Observamos algunos hepatocitos bi-nucleados. Evidentes espacios en el parénquima deben ser emplazamientos de almacenamiento de los lípidos en el hígado. Los lóbulos hepáticos clásicos presentan una vena central rodeada de varias células hepáticas. En la tríada portal, se observó la vena hepática, las arterias hepáticas y los conductos biliares, mientras que las arterias y venas hepáticas estaban revestidas por endotelio, los conductos biliares estaban alineados por células cuboides simples. También se observaron fibras nerviosas en la región de la tríada portal. Sinusoides hepáticos revestidos por endotelio fueron observados entre los lobulillos hepáticos en el parénquima hepático. Los sinusoides contenían macrófagos. El presente estudio ayudará a los biólogos de la fauna silvestre en una investigación más precisa, y a los médicos veterinarios en el diagnóstico de las enfermedades hepáticas en la ardilla de palma africana.

The topography and gross anatomy of the abdominal gastrointestinal tract of the Persian squirrel (Sciurus anomalus) / La topografía y anatomía macroscópica del tracto gastrointestinal abdominal de la ardilla persa (Sciurus anomalus)

The persian squirrel (Sciurus anomalus) is the only member of the Sciuridae family found in the Middle East. It is herbivorous, feeding mostly on pine acorns and other seeds and fruits. It is a wild animal nesting in forest trees, although it is frequently found close to city gardens and parks. As Persian squirrels are also found in homes as "companion animals", veterinarian assistance may be sometimes required; this is a good reason to gain more specific knowledge of the anatomical features of this animal. Due to the scantiness of relevant literature, we carried out this study with the aim to provide further information on the topography and gross anatomy of its abdominal gastrointestinal tract (GIT). Seven animals of this species were utilized to measure the length, content weight and area surface of the relative segments of the abdominal GIT. The stomach is unilocular, lined with glandular epithelium; the small intestine is divided into duodenum, jejunum and ileum. The cecum is situated on the right side of the abdominal cavity and lacks the vermiform appendix observed in some rodents. The ascending colon is extensive, consisting of two loops and two straight parts forming a unique topographic arrangement, closely resembling the ascending colon of the horse. The transverse colon connects the ascending and the descending colon located on the left side of the abdominal cavity, and shows a distinct sigmoid flexure before entering the pelvic cavity. Overall, the in situ examination and the relative measurements of the various parts of the abdominal GIT suggest that the ascending colon is the main fermentation chamber in the Persian Squirrel.

La ardilla es el único miembro de la familia de los Sciuridae que se encuentra en el Medio Oriente. Es un herbívoro, come semillas, principalmente de pino, y fruta. Vive mayormente en el bosque en estado salvaje, aunque a veces se puede encontrar en las ciudades, en parques y jardines. Las ardillas persianas tambien se tienen en casas como mascotas y algunas veces es necesaria la atención del veterinario. Esta es una buena razón para conocer más profundamente sus características anatómicas. Teniendo en cuenta la escasa bibliografía existente a cerca de este animal, el objetivo de este estudio fue aportar nueva información sobre la anatomía topográfica y mascroscópica del tracto abdominal gastrointestinal (GIT) de la ardilla. Siete animales de esta especie han sido utilizados para medir el largo, el peso y el área de la superficie de los segmentos del GIT. El estómago es unilocular, alineado con epitelio glandular; el pequeño intestino está dividido en duodeno, jejuno e ileo. El ciego está localizado en la parte derecha de la cavidad abdominal y le falta el apéndice vermiforme que poseen los roedores. El colon ascendente es extenso, constituido de dos partes curvas y dos rectilíneas que forman una única dispoción topográfica cerrada como el colon ascendente en el caballo. El colon trasverso, que conecta el ascendente y el descendente, está localizado en el lado izquierdo de la cavidad abdominal y muestra una clara flexión sigmoide antes de entrar en la cavidad pélvica. En resumen, el examen in situ y las relativas medidas de las varias partes del GIT sugieren que el colon ascendente es la principal "cámara" de fermentación en la ardilla persiana.

Transient elevations of AChE in soleus, plantaris and EDL muscles of palm squirrel (Funambulus palmaram) during prolonged reinnervation.

Recovery of acetylcholinesterase (AChE) activity after nerve crush was observed at second week in soleus (slow-extensor) and plantaris (fast-extensor) muscles whereas the same was observed in extensor digitorum longus (fast-flexor) only after third week. In contrast to earlier observations the AChE was found to exhibit specific transient elevations with intermittent reversal to control values in different type of skeletal muscles during later periods of reinnervation.

Displaced amacrine cells in the ganglion cell layer of the ground squirrel retina

In some mammals a large portion of the retinal neurons of the ganglion cell layer are not ganglion cells. These neurons, lacking axons which pass to the brain via the optic nerve, are termed displaced amacrine cells. The present study assessed the number of displaced amacrine cells in the thirteen-lined ground squirrel (Spermophilus tridecemlineatus). We compared the number of labeled cells in the ganglion cell layer after HRP injection of optic tracts and target nuclei with the total number of neurons in the ganglion cell layer. We conclude that approximately one half of the neurons in the ganglion cell layer are displaced amacrine cells, the other one half are ganglion cells. The displaced amacrine cells are on the average smaller than the ganglion cells. Our results provide a rationale for renewed study of relation of ganglion cell morphology and physiological functional type in this species

Morphology and distribution of dopaminergic neurons in the ground squirrel retina

Tyrosine hydroxylase (TH), the rate limiting enzyme in the conversion of tyrosine to DOPA, is a reliable marker for catecholaminergic (dopaminergic) neurons. To investigate the distribution of dopamine in the retina of the thirteen-lined ground squirrel (Spermophilus tridecemlineatus), retinal sections and wholemounts were incubated with an antiserum directed against TH and then processed using the avidin-biotin immunohistochemical method. TH-like immunoreactivity was exhibited by amacrine and interplexiform-like cells in the innermost portion of the inner nuclear layer (INL) and by cells we presume to be displaced amacrines in the ganglion cell layer (GCL). Their somata were 12 to 20 microns in diameter, with the majority measuring approximately 18 microns. In transverse sections the processes of the three types of neurons were seen to extend into lamina 1 of the inner plexiform layer (IPL). In horizontal sections 2-3 primary dendrites were seen to ramify and the branches extended for considerable distances, with overlap between the dendritic fields of neighboring TH cells. A distance to the nearest neighbor analysis suggests the TH-neurons in the INL are distributed in a non-random fashion

Connections of the parabigeminal nucleus in ground squirrel: a horseradish peroxidase study

Las conecciones anatómicas del núcleo parabigémino (Pb) de la ardilla terrestre fueron determinadas por medio del método de peroxidasa de rábano (HRP). Luego de hacer inyecciones de HRP en las láminas superiores del colículo superior (SC). Se encontraron neuromas marcadas con HRP en los Pb ipsilateral y contralateral; solo se observaron terminales de axón marcados en el Pb ipsilateral. Estas conecciones mostraron alguna organización topológica. Las células marcadas en Pb eran multipolares o fusiformes. Mientras que un número mayor de células aparecieron marcada en el Pb ipsilateral, las células marcadas del Pb contralateral eran mayores en tamaño. Luego de hacer inyecciones de HTP en el núcleo parabigémino, se observaron células marcadas en las capas superficiales del SC ipsilateral. Las neuronas marcadas con HRP en SC eran células fusiformes y piriformes de tamaño mediano y neuronas multipolares pequeñas. Las conecciones anatómicas del núcleo parabigémino con las láminas superficiales del tecto sugieren un rol en el procesamiento de información visual