Is the Pig a Good Animal Model for Studying the Human Ileal Brake?

1998 ◽  
Vol 87 (5) ◽  
pp. 565-568 ◽  
Author(s):  
Clair L. Dobson ◽  
Mike Hinchcliffe ◽  
Stanley S. Davis ◽  
Sushil Chauhan ◽  
Ian R. Wilding
Keyword(s):  
Animal Model ◽  
Ileal Brake ◽  
Good Animal Model

Meridional Variation in Visual Acuity of Hooded Rats Reared in a Carpentered Environment

Perception ◽  
1981 ◽  
Vol 10 (4) ◽  
pp. 423-430 ◽  
Author(s):  
Paul Dean ◽  
Phillip Horlock ◽  
Ian M Strachan
Keyword(s):  
Animal Model ◽  
Visual Acuity ◽  
Visual Cortex ◽  
Low Frequency ◽  
Oblique Effect ◽  
Neural Mechanisms ◽  
High Contrast ◽  
Square Wave ◽  
Laboratory Rats ◽  
Good Animal Model

Resolution acuity in people is frequently better for horizontal and vertical gratings than for obliques. An animal model of this oblique effect might be of help in elucidating its underlying neural mechanisms. Rats were chosen because laboratory rats are reared in a ‘carpentered environment’ apparently similar to those proposed to cause the oblique effect in people, and because electrophysiological experiments suggest that orientation selective units in rats' visual cortex may prefer horizontal and vertical stimuli. The acuity of eight laboratory-reared hooded rats was measured with high-contrast horizontal, vertical, and oblique gratings. The animals learned to detect low-frequency square-wave gratings with slightly fewer errors if they were horizontal or vertical than if they were oblique, but the effects of grating orientation on acuity were not significant. Refraction of the rats' eyes gave no evidence of astigmatism. These results suggest that the rat may not be a good animal model for studying the mechanisms that underlie meridional variations in acuity in people, and raise questions concerning both the neural bases of resolution acuity, and the validity of the ‘carpentered environment’ hypothesis.

Depth from shading and disparity in humans and monkeys

2007 ◽  
Vol 24 (2) ◽  
pp. 207-215 ◽  
Author(s):  
YING ZHANG ◽  
VERONICA S. WEINER ◽  
WARREN M. SLOCUM ◽  
PETER H. SCHILLER
Keyword(s):  
Animal Model ◽  
Visual System ◽  
Depth Perception ◽  
Discrimination Task ◽  
Stimulus Display ◽  
Neural Mechanisms ◽  
Depth Information ◽  
Depth Cues ◽  
Good Animal Model

A stimulus display was devised that enabled us to examine how effectively monkeys and humans can process shading and disparity cues for depth perception. The display allowed us to present these cues separately, in concert and in conflict with each other. An oddities discrimination task was used. Humans as well as monkeys were able to utilize both shading and disparity cues but shading cues were more effectively processed by humans. Humans and monkeys performed better and faster when the two cues were presented conjointly rather than singly. Performance was significantly degraded when the two cues were presented in conflict with each other suggesting that these cues are processed interactively at higher levels in the visual system. The fact that monkeys can effectively utilize depth information derived from shading and disparity indicates that they are a good animal model for the study of the neural mechanisms that underlie the processing of these two depth cues.

scholarly journals Comparative analysis of dentate gyrus from naive Wistar rats and human hippocampus using molecular tools

2018 ◽  
Author(s):  
Alexandre Barcia de Godoi ◽  
Iscia Teresinha Lopes Cendes ◽  
Amanda Morato do Canto ◽  
Alexandre Hilário Berenguer Matos ◽  
André S. Vieira ◽  
...  
Keyword(s):  
Animal Model ◽  
Comparative Analysis ◽  
Wistar Rats ◽  
Hippocampal Formation ◽  
Mesial Temporal Lobe Epilepsy ◽  
Suitable Model ◽  
Molecular Tools ◽  
Human Hippocampus ◽  
Mesial Temporal Lobe ◽  
Good Animal Model

Much of the studies related to the hippocampus are aimed to elucidate the diseases which affect this structure, such as Mesial Temporal Lobe Epilepsy (MTLE) and Alzheimer’s disease (AD). However, to better understand the pathophysiology of these diseases, which are not fully elucidated, we must focus in other structures from the Hippocampal Formation, that can be involved with these mechanisms, such as the DG¹. The DG itself is also subdivided into dorsal and ventral in rodents and posterior and anterior in humans². Moreover, the neurodegenerative diseases, as others, are usually investigated using animal models, mainly rodents, due to its possibility of study the development of the diseases and not only its final stage³. However, despite its remarkable similarities with humans, it is necessary to evaluate the differences between the two species to validate the rodents as a suitable model for human pathologies. Therefore, here we present the comparative multi-OMICs analysis of the laser microdissected DG from rat and humans, intending to characterize and describe both species, validating the rat as a good animal model for human pathologies. We also present the comparative analysis of dorsal and ventral DG isolated from the rats.

Interactions of sperm and the reproductive ducts of the male tammar wallaby, Macropus eugenii (Macropodidae: Marsupialia)

1994 ◽  
Vol 6 (4) ◽  
pp. 437 ◽  
Author(s):  
RC Jones ◽  
J Clulow
Keyword(s):  
Animal Model ◽  
Inorganic Ions ◽  
Tammar Wallaby ◽  
Duct System ◽  
Sperm Production ◽  
Structural Differentiation ◽  
Macropus Eugenii ◽  
Cauda Epididymidis ◽  
Good Animal Model

This review compares sperm production in the tammar wallaby and eutherian mammals, particularly the rat. The capacity of sperm to fertilize an ovum when they leave the testis and the changes they undergo in the epididymidis are considered. The structural differentiation and regulation of the extratesticular duct system is assessed and related to the reabsorption and secretion of water, inorganic ions and proteins, and the interaction of sperm and proteins synthesized and secreted by the epididymidis. Adaptations of the cauda epididymidis for storing spermatozoa are also considered. It is suggested that the tammar may be a good animal model to study the suppression of sperm motility and metabolism in the cauda epididymidis as it is possible to collect from them luminal samples of sperm which are initially immotile and then spontaneously activate during incubation in vitro.

Risk Factors for Infant Abuse and Neglect in Group-Living Rhesus Monkeys

1998 ◽  
Vol 9 (2) ◽  
pp. 143-145 ◽  
Author(s):  
Dario Maestripieri ◽  
Kelly A. Carroll
Keyword(s):  
Risk Factors ◽  
Animal Model ◽  
Intergenerational Transmission ◽  
Rhesus Monkeys ◽  
Large Population ◽  
Group Living ◽  
Maternal Abuse ◽  
Abuse And Neglect ◽  
Infant Neglect ◽  
Good Animal Model

This study investigated maternal abuse and neglect of offspring in a large population of rhesus monkeys over a period of 29 years. Abuse and neglect did not occur together and were associated with different risk factors. Infant abuse was concentrated in 8 of 57 families and among closely related females. Abuse was also repeated with successive offspring. In contrast, infant neglect was not affected by genealogical factors, was not repeated with successive offspring, and was displayed mostly by primiparous mothers. These results suggest that abuse and neglect may be different phenomena and that infant abuse in group-living monkeys could represent a good animal model for investigating the mechanisms underlying the intergenerational transmission of child maltreatment.

Haemoperfusion treatment in pigs experimentally intoxicated by paraquat

1997 ◽  
Vol 16 (12) ◽  
pp. 709-715 ◽  
Author(s):  
TS Yang ◽  
YL Chang ◽  
CK Yen
Keyword(s):  
Renal Failure ◽  
Animal Model ◽  
Renal Clearance ◽  
Intramuscular Injection ◽  
Domestic Pigs ◽  
Paraquat Poisoning ◽  
Concentration Peak ◽  
Renal Morphology ◽  
Toxin Removal ◽  
Good Animal Model

1 Because of their similarity in renal morphology and physiology to humans, domestic pigs (gilts, 70 kg) were bolus treated by intramuscular injection of 74,17, and 6 mg kg-1 and by oral loading (70 mg kg-1 n=4) of paraquat. The concentration peak of plasma paraquat was reached at 1.5 - 2.5 h. Renal clearance of paraquat rose to its maximum at 5 - 6 h after intoxication and then sharply decreased indicating renal failure. All the intoxicated pigs died. 2 An additional 10 gilts were also orally treated with 70 mg kg-1 paraquat but received haemoperfusion from 2 h post intoxication for either 2 h (n=6) or 6 h (n=4). The 2 h haemoperfusion resulted in a 5.1% toxin removal but failed to save any of six poisoned pigs. Prolonged 6 h haemoperfusion successfully rescued three out of four intoxicated pigs. 3 The plasma paraquat concentrations of the three surviving pigs were above 2 mg l -1 at 10 h post intoxication. This level is not only similar to those of untreated animals that died later, but also well beyond the suggested limit for survival of poisoned patients. 4 Pigs proved to be a good animal model for studies in paraquat poisoning and/or haemoperfusion. It is also suggested that early haemoperfusion is effective in treating paraquat poisoning even in very severe cases due to its possible detoxicating effect in addition to toxin removal.

Ultrastructural investigation of spontaneous pituitary gonadotroph cell adenomas in aging Sprague-Dawley rats

1983 ◽  
Vol 41 ◽  
pp. 702-703
Author(s):  
D. J. McComb ◽  
J. Beri ◽  
F. Zak ◽  
K. Kovacs
Keyword(s):  
Electron Microscopy ◽  
Animal Model ◽  
Epoxy Resin ◽  
Immunoelectron Microscopy ◽  
Tumor Type ◽  
Gonadal Function ◽  
Sprague Dawley ◽  
Male And Female ◽  
Reticulin Fibers ◽  
Sprague Dawley Rats

Gonadotroph cell adenomas of the pituitary are infrequent in human patients and are not invariably associated with altered gonadal function. To date, no animal model of this tumor type exists. Herein, we describe spontaneous gonadotroph cell adenomas in old male and female Sprague-Dawley rats by histology, immunocytology and electron microscopy.The material consisted of the pituitaries of 27 male and 38 female Sprague Dawley rats, all 26 months of age or older, removed at routine autopsy. Sections of formal in-fixed, paraffin-embedded tissue were stained with hematoxylin-phloxine-saffron (HPS), the PAS method and the Gordon-Sweet technique for the demonstration of reticulin fibers. For immunostaining, sections were exposed to anti-rat β-LH, anti-ratβ-TSH, anti-rat PRL, anti-rat GH and anti-rat ACTH 1-39. For electron microscopy, tissue was fixed in 2.5% glutaraldehyde, postfixed in 1% OsO4 and embedded in epoxy-resin. Tissue fixed in 10% formalin, embedded in epoxy resin without osmification, was used for immunoelectron microscopy.

Electron Microscopic Detection and Characterization of Nonhuman Primate Enteric Viruses

1982 ◽  
Vol 40 ◽  
pp. 306-307
Author(s):  
G. C. Smith ◽  
R. L. Heberling ◽  
S. S. Kalter
Keyword(s):  
Electron Microscopy ◽  
Animal Model ◽  
Nonhuman Primate ◽  
Clinical Condition ◽  
Intestinal Tract ◽  
Enteric Viruses ◽  
Electron Microscopic ◽  
Microscopic Detection

A number of viral agents are recognized as and suspected of causing the clinical condition “gastroenteritis.” In our attempts to establish an animal model for studies of this entity, we have been examining the nonhuman primate to ascertain what viruses may be found in the intestinal tract of “normal” animals as well as animals with diarrhea. Several virus types including coronavirus, adenovirus, herpesvirus, and picornavirus (Table I) were detected in our colony; however, rotavirus, astrovirus, and calicivirus have not yet been observed. Fecal specimens were prepared for electron microscopy by procedures reported previously.

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