The lesions consist of perivascular lymphocytes, inflammatory cells and alveolar macrophages in the lung alveoli and the presence of epithelial hyperplasia. These inclusions are negative for periodic acid–Schiff (PAS), Alcian Blue, Von Kossa, mucicarmine, phosphotungstic acid hematoxylin (PTAH), Masson’s trichrome, Congo Red, and toluidine blue stains (Monticello et al 1990). Heart valve cysts may occasionally be observed in the heart valves of rats (Fig. 2.3) is also known as endocardial hyperplasia, endocardial disease, endomyocardial disease or subendocardial fibrosis. 2.7a). The cause is either congenital or traumatic injury (Stefanski et al 1990). In rats, there are, at present, only four reports of intraoral ‘ectopic’ sebaceous glands in the literature (Bernick & Bavetta 1962, Squamous cysts (Fig. Multifocal hemorrhage (and occasionally eosinophilic crystals) is very common in the thymus of rats, particularly as an agonal lesion due to carbon dioxide euthanasia (Frith et al 2000b) (Fig. Squamous cyst filled with keratin near limiting ridge in the rat stomach. Log In or, Click to share on Twitter (Opens in new window), Click to share on Facebook (Opens in new window), Click to share on Google+ (Opens in new window), Almost all laboratory and domestic pet rats belong to a single species, the Norway rat (, Cardiomyopathy (Fig. ×100. Congestion is a common background lesion of the spleen and may be linked to the method of euthanasia (. FIGURE 2.14 Capsular cyst in rat spleen. Try out the SAS Sprague Dawley rat with our animal model evaluation program→ ", Two rats belong to the same variety if they share the trait in question, regardless of the rats' ancestry. For example, rats with curly fur belong to the "rex" variety, rats with low-set ears are called "dumbo," rats without hair are called "hairless. Almost all laboratory and domestic pet rats belong to a single species, the Norway rat (Rattus norvegicus). Use an outbred stock of rat such as the Wistar Han or the Sprague Dawley NTP temporarily switched to the F344/NTac rat and then selected the Wistar Han rat [Crl:WI (Han)]. Rats were received at RBU 3, Taconic Biotechnology, Albany NY and acclimated for three days on irradiated NIH #31M Rodent Diet and sterilized water ad lib, sterile contact bedding (paper chip) and a 12:12 light:dark cycle. Rather, "rat" is a common term for rodents that look alike to the casual eye, regardless of ancestry: they are medium-sized rodents with long tails. Medial degeneration is common in the coronary arteries of rats and the affected vessels display enlarged, irregularly arranged and sparse nuclei present in a PAS-positive matrix (Ruben 2000). In addition, tattoo pigment which has drained to the peripheral lymph nodes may occasionally be observed in rat lymph nodes (Fig. The rat is the most commonly used rodent species for toxicology studies. ZERO BIAS - scores, article reviews, protocol conditions and more Increased extramedullary hematopoiesis is a common lesion in the rat spleen (Fig. Kangaroo rats are only distantly related to Norway rats. ×100. Minimal apoptosis of the rat thymic cortex. FIGURE 2.37 Osseus metaplasia in the rat lung. Sprague Dawley rats can live up to 3.5 years and grow to an adult body weight of 250-300 grams for females and 450-520 grams for males. 2.44), often containing keratin, are common in the stomach, particularly in the region of the limiting ridge and antral mucosa. The neoplasm appears to originate in the spleen, but also com- monly involves the liver and lung. Dilated submucosal glands in the larynx of the rat. 2.31) is a common aging change in rats and is observed in most two-year-old rats on carcinogenicity studies. ×100. FIGURE 2.7a Vaso vasorum in adventitia of a mesenteric artery blood vessel in the rat. Sprague Dawley Rat Serum (1mL, 5mL, 10mL, 50mL, 100mL): Buy Serum derived from whole blood of normal, pooled or single Rat (Sprague Dawley) donors. The pathogenesis is unknown but may be related to immune complex disease. Thymus hemorrhage and eosinophlilic crystals. 2.4) (. ×200. ( index of major rat strains; rat genome database ). FIGURE 2.25 Alveolar hemorrhage with erythrophagocytosis in the rat lung. ×200. 2.32) are generally found in the bronchiolar epithelium. Eosinophilic perivascular infiltration in the rat lung. FIGURE 2.15 Minimal extramedullary hemopoiesis in a rat spleen. ×100. The aggregates may represent resolved inflammatory foci and may represent a focal deficit in the pulmonary clearance mechanisms. ×200. 1990). 2.7b). Sprague Dawley rats are an outbred strain of albino laboratory rats belonging to the species Rattus norvegicus. ×200. Hypertrophy and hyperplasia of the endocardium may be seen in conjunction with the myxomatous valvular changes. Alveolar hemorrhage with erythrophagocytosis in the rat lung. strain Wistar ›Sprague-Dawley rat ›Wistar rats ›brown rat ›laboratory rat ›rats ›zitter rats Cartilaginous foci at the base of the aorta are common in both young and old Sprague–Dawley rats (Fig. The lesion consists of a large mass of dentine-like material with fragments of tooth and bone (Bertram et al 1996). Figuring out what category a rat belongs to means tallying up the traits it has and stringing the traits together into a descriptive name. FIGURE 2.4 Cartilage at base of aorta in a rat. ×200. Author links open overlay panel. This animal is not an exemplar of a breed of chocolate hooded rex rats. Showcase your research with Agilent MVP Rat Total RNA (MVP Sprague-Dawley Rat, Male, Total RNA) - application-ready RNA available in economical and convenient 200 µg packs. Pulmonary neuroendocrine cells are found as clusters called neuroepithelial bodies or as single cells scattered in the respiratory epithelium (Haworth et al 2007). Eosinophilic inclusions in the olfactory epithelium of the rat nasal turbinate. There are two common rats strains used known as Sprague-Dawley and Wistar in Mesenchymal stem cell field throughout the years. Endocardial myxomatous change occurs in older rats and is recognized by focal or diffuse thickening in the subendocardium due to the presence of myxomatous tissue (Ruben 2000). 2.12). Pleural lung tag on surface of rat lung. The lesion consists of fibrinoid degeneration of the media with inflammatory cell infiltration progressing to fibrosis, vascular dilatation, occlusion and aneurysm (Mackenzie & Alison 1990). Most laboratory rat strains descend from a colony of rats established at the Wistar Institute in 1906. Foci of mineralized concretions or corpora amylacea (Fig. Almost all laboratory and domestic pet rats belong to a single species, the Norway rat (Rattus norvegicus). Cystic dilatation of the lymph nodes may be so prominent that it is noted at necropsy. ×200. Atrial (left) and ventricular thrombosis are occasionally associated with cardiomyopathy in aging rats. The crystals may be associated with areas of alveolar hemorrhage (Fig. Thymic cysts are often lined by squamous cells or ciliated epithelium. 2.8) (particularly the medullary or subscapular sinuses) of the lymph nodes are observed commonly in rats. The aim of the study was to measure the body surface area of Sprague-Dawley rats … Morphological differences, on the other hand, are differences in form or function, and therefore tend to be external and visible. 2.20) (also known as involution) is a common background finding in aged rats. ×100. Occasionally pleural tags (Fig. 2.29) is found occasionally in Wistar rats, but is more common in Fischer rats (. FIGURE 2.40 Mineralization of mucus within the lumen of the nasal turbinates of the rat. Liver microsomes prepared from a pool of male Sprague Dawley rats Total protein concentration 20 mg mlWe provide liver subcellular fractions from a variety of tox species including human nonhuman primates Cynomolgus Monkey and Rhesus Monkey dog Beagle rat Sprague Dawley mouse CD 1 and Balb c and trout Oncorhynchus mykiss Custom species are available upon … * P < 0.001. A purebred animal (again according to Webster's) refers to a member of a recognized breed, strain or kind without admixture of other blood over many generations. So, beagle and Doberman are examples of different dog breeds. Information about genome files, completeness, GC-content, size, N50-values, and sequencing methods are listed. The rat found early use in laboratory research in five areas: W. S. Small suggested that the rate of learning could be measured by rats in a maze; a suggestion employed by John B. Watson for his Ph.D. dissertation in 1903. Hemosiderin pigment is occasionally observed in the bone marrow and may be associated with previous hemorrhage (Frith et al 2000b). We have created the immunodeficient SRG rat, a Sprague-Dawley Rag2/Il2rg double knockout that lacks mature B cells, T cells, and circulating NK cells. However, the term strain tends to refer to physiological differences, while the term breed tends to refer to morphological differences. The common term "rat" is not a phylogenetic classification (meaning it does not describe a group of closely related species). ×100. FIGURE 2.3 Endocardial mesenchymal proliferation in the rat heart. Ten rats, including 5 rats from … The alveolar macrophages often contain abundant, foamy cytoplasm (. ×100. However, this drug is an extremely weak CYP3A inducer in the most commonly used laboratory animal species for toxicological studies — Sprague–Dawley (SD) rats. 2.17). This chapter will give an overview of background lesions encountered in both young and older Wistar and Sprague-Dawley rats. Minimal extramedullary hemopoiesis in a rat spleen. A hair embolus within an artery in the rat lung, surrounded by inflammatory cells. The reproductive functionof rats was studied at the I… They belong to the same family Muridae, but cotton rats are in a different genus, called Sigmodon, while Norway rats are in the genus Rattus. 2.21). These consist of pleural extensions which often contain mononuclear cells such as lymphocytes. ×200. Hair shaft emboli or skin fragment emboli are seen in the lungs of animals on intravenous injection studies. ×200. ×100. BBB score showed a significant improvement in F344 and SPD as compared to LEW rats. Small areas of alveolar hemorrhage (Fig. FIGURE 2.45 Cyst lined by ciliated epithelium in the non-glandular stomach of the rat. ×400. Cartilagenous and osseous metaplasia of the chorda tendinae may occur at the end stage of the disease (Ruben 2000). Multifocal aggregates of alveolar macrophages (Fig. FIGURE 2.8 Macrophages with brown pigment in the mesenteric lymph node. A breed, according to Webster's Dictionary again, is a group of animals presumably related by descent from common ancestors and visibly similar in most characteristics. What are these different kinds of rats? 2.16) is observed as a background lesion in rats. Eosinophilic crystals in the rat lung. 2.27) (also known as alveolar histiocytosis) within alveoli and terminal airways are observed in both young and old rats. In addition to the incisor and molar area, the buccal mucosa as well as the hard palate and tongue should also be considered as possible sites of occurrence of Fordyce’s granules in rats. Tatto pigment in a rat popliteal lymph node. ×200. Sprague-Dawley rat strain was derived from this strain. An inbred strain is defined as the product of over 20 generations of brother-sister matings, which results in individuals that are 98% identical to each other. Wistar, Fisher, and Sprague Dawley, and their hundreds of internal divisions, are examples of rat strains. Special stains (such as Schmorl’s for lipofuscin) should be used to distinguish ceroid pigment from iron (Perl’s-positive) or melanin (Masson Fontana-positive). Small capsular cysts may occur on the surface of the rat spleen (Fig. CD® (Sprague Dawley) IGS Rat Details. On television, we hear about wood rats and kangaroo rats and black rats and Norway rats. FIGURE 2.29 Brown pigmented alveolar macrophages in the rat lung. The lesion is not associated with metastatic calcification. There's obviously some overlap between the two terms: both refer to subgroups of individuals in a given species which share common traits due to common descent. Thymic cysts (. 2.34). FIGURE 2.35 Eosinophilic crystals in the rat lung. 3-Butene-1,2-diol (BDD) is a major metabolite of 1,3-butadiene (BD), but the role of BDD in BD toxicity and carcinogenicity remains unclear. Mesenchymal proliferation in the subendocardium (Fig. The etiology and significance of the lesion are unknown, but the lesion is particularly common in mandibular lymph nodes, particularly in conjunction with oral cavity lesions. Moderate amounts of intracellular pigment (generally lipofuscin) are often noted in the medullary area. Its main advantage is its calmness and ease of handling. FIGURE 2.23 Mineralization (corpora amylacea) of the olfactory epithelium of the rat nasal turbinate. Information about genome files, completeness, GC-content, size, N50-values, and sequencing methods are listed. Simi-larly, in 2,146 control male and 2,344 control female SD (Crl:CD) rats, there were no cholangiocarcinomas and 8 Four weeks after dosing, the animals were … ×100. ×100. ×200. FIGURE 2.18 Thymic cysts lined by squamous epithelium. Dental dysplasia is often observed in conjunction with inflammation and trauma. ×400. These foreign bodies generally induce a granulomatous reaction consisting of multinucleated giant cells and other inflammatory cells (Renne et al 2003) (. ×20. ZERO BIAS - scores, article reviews, protocol conditions and more 2.10), particularly the mandibular lymph node, are observed frequently in the lymph nodes of both young and old rats. Norway rats and kangaroo rats aren't that closely related at all. This lesion is common and generally occurs due to the presence of hemorrhage in the organs draining into the lymph nodes. 2.8) (particularly the medullary or subscapular sinuses) of the lymph nodes are observed commonly in rats. Thymic atrophy or involution in the rat thymus. FIGURE 2.26 Proliferation of neuroendocrine cells in bronchiole of rat lung. As the atrophy progresses, the epithelial components of the thymus become more prominent and often form tubular structures (Stefanski et al 1990). Perl’s-positive hemosiderin pigment present in the red pulp of a rat spleen. A variety is therefore a purely descriptive category, it says nothing about the biological relationship between rats. 2.22). It is found most frequently in the subintimal myocardium of the left ventricular wall and is more common in male rats (MacKenzie & Alison 1990). Also known as 'Rattus rattiscus (misnomer),Gunn rats (misnomer)' or 'brown rat, rat ,(German: Hausratte, Wanderratte)'. Globule leukocytes are present in the respiratory epithelium of the larynx and trachea in rats (Renne et al 2003, 2009). Mural mineralization of an artery in the rat lung. 2.44), often containing keratin, are common in the stomach, particularly in the region of the limiting ridge and antral mucosa. FIGURE 2.6 Medial hypertrophy in heart artery. There are many different species of rodent in the wild that bear the common name "rat." The number of animals was based on consultation with a statistician and determined to be sufficient to provide sufficient power in light of preliminary observations of 2 … ×200. ×100. ×200. ×200. ×100. The lesion is characterized initially by necrotic, eosinophilic cardiomyocytes surrounded by fibroblasts and inflammatory cells (Fig. The Jackson Laboratory rat novel object recognition test male sprague dawley rats Rat Novel Object Recognition Test Male Sprague Dawley Rats, supplied by The Jackson Laboratory, used in various techniques. 2.11) is found predominantly in the medullary cords (Stefanski et al 1990). Clara cells (Fig. Biliary Proliferative Lesions in the Sprague-Dawley Rat: Adverse/Non-adverse JAMES R. HAILEY 1,JAMES B. NOLD 2,ROGER H. BROWN 1,JOHN M. CULLEN 3,JULIE C. HOLDER 4,HOLLY L. JORDAN 1, DANIELA ENNULAT 5, AND RICHARD T. MILLER 1 1GlaxoSmithKline, Research Triangle Park, North Carolina, USA 2WIL Research/Biotechnics, Hillsborough, North Carolina, …