Ultrasonography of the normal kidney in the cynomolgus monkey (Macaca fascicularis): morphologic and Doppler findings

The purpose of this study was to obtain sonographic measures of normal kidneys in cynomolgus monkeys (Macaca fascicularis). The kidneys of 27 healthy female cynomolgus monkeys were examined with two-dimensional, duplex and power Doppler under sedation or general anesthesia. Except for shape and sinus echogenicity, the kidneys of the cynomolgus monkey are morphologically similar to those of humans. Left kidney volume estimations (mean, 5.1 cm3) were significantly smaller (P<0.001) than those of the right (mean, 5.9 cm3), and both increased significantly with increasing body weight (P<0.05, r = 0.408). The mean resistive index (RI) of ketamine-sedated monkeys was 0.54, with an upper limit of 0.74 for the renal artery. The mean RI under general anesthesia was 0.65, with an upper limit of 0.77. Morphologic and Doppler ultrasound assessments of the kidneys can be consistently performed in the conscious cynomolgus monkey, and anesthesia can have hemodynamic effects that alter the Doppler arterial waveform.     

Spontaneous renal lymphosarcoma in a juvenile cynomolgus monkey (Macaca fascicularis)

Spontaneous lymphosarcoma, likely of renal origin, was diagnosed in a naive, juvenile, male cynomolgus monkey (Macaca fascicularis). Histologically, renal architecture was effaced by dense infiltrating sheets of plump cells with indistinct borders and scant amphophilic cytoplasm. Mitoses were uncommon. Similar neoplastic infiltrates were also present in the right renal cortex, one adrenal medulla, the prostate, seminal vesicles, myocardium, and the pulmonary interstitium. Serological tests were negative for infection with Simian Immunodeficiency Virus (SIV), Simian T-Lymphotropic Virus-1 (STLV-1), and Simian Retrovirus-5.     

Alkaptonuria in a cynomolgus monkey (Macaca fascicularis)

An eight year old wild caught Cynomolgus monkey was diagnosed as having alkaptonuria, a condition characterized by the passage of a normal-colored urine which darkens upon standing. The underlying cause is the congenital lack of homogentisic acid oxidase with subsequent passage of homogentisic acid in the urine. No other clinical manifestations, such as deposition of pigment in the skin or mucous membranes or development of an ochronitic arthritis, were observed in this animal.     

Ameloblastic odontoma in a cynomolgus monkey (Macaca fascicularis)

An ameloblastic odontoma occurred in an adult cynomolgus monkey (Macaca fascicularis). The neoplasm involved the upper left maxilla as a disfiguring, fleshy growth. The tissue and cellular changes were consistent with an ameloblastic odontoma which is rare in man, nonhuman primates (NHP), and other vertebrate animals. The monkey was one of 50 adult, single-caged housed cynomolgus monkeys. No additional clinical signs of disease were present. Hematology and serum chemistries were within normal limits. There have been three reports in the literature of ameloblastic odontomas in NHP; however, this is the first reported case of an ameloblastic odontoma in a cynomolgus monkey.     

Spontaneous endometriosis in a cynomolgus monkey (Macaca fascicularis)

An adult female Macaca fascicularis developed anorexia and minimal fecal production. Abdominal palpation was unrewarding. Rectal palpation revealed a rectal stricture and a large soft tissue mass in the area of the uterus. Clinical pathology tests were within normal limits. Exploratory surgery and histopathology confirmed a diagnosis of endometriosis.     

Early embryonal culture of the cynomolgus monkey (Macaca fascicularis)

Ovaries of ten female cynologus monkeys (Macaca fascicularis) were superstimulated with pregnant mare serum gonadotropin (PMSG) and human chorionic gonadotropin (hCG). During this treatment, follicular development was monitored by ultrasonography. After three to four injections of PMSG, ovaries began to show an increase in their size. After seven to ten injections of PMSG and a hCG injection, a total of 183 oocytes (18.3±14.1/ animal, mean±SD) were recovered from these females by laparotomy. Five nulliparous females produced 24.2±18.2 oocytes per animal, and the remaining five parous females produced 12.5±5.46 oocytes per animal. In total, 133 (72.6%) of the 183 oocytes were classified morphologically as matured, and 130 of them were inseminated with cynomolgus monkey sperm for 18 hours in vitro. The second polar body was observed in 92 (71%) of the inseminated oocytes, and 54 (59%) of the 92 oocytes showed cleavage division at least once. When these oocytes were fertilized and cultured in serum-free media, they stopped their development at 4-cell stage. In contrast to this condition, about a half of fertilized oocytes in serum-free media were able to develop to morula stage 4 days after insemination by transferring them into serum-containing media after 2-cell stage.     

Neuronal ceroid-lipofuscin storage in a cynomolgus monkey (Macaca fascicularis)

The light and electron microscopical characteristics of non-age-related neuronal ceroid-lipofuscinosis in a young cynomolgus monkey (Macaca fascicularis) are described. The pigment in the neuronal cytoplasm was PAS-positive, sudanophilic, weakly acid-fast, and positive with Schmorl's and aldehydefuchsin stains for lipofuscin. Ultra-structurally, it appeared as membrane-bound, electron-dense aggregates within the cytoplasm of neurones of both brain and spinal cord.     

Morphological characterization of ejaculated cynomolgus monkey (Macaca fascicularis) sperm

The aim of this study was to give reference values for the frequency of morphological sperm abnormalities present in the semen from nonexperimental cynomolgus monkeys as well as for the dimensions of sperm heads. Spermatozoa from the liquid portion of electroejaculates from 14 cynomolgus monkeys were air‐dried as smears, fixed, and stained with Harris's Haematoxylin and subjected to visual analysis of morphology and computer‐aided analysis of ten morphometric variables. The majority (83%) of sperm were morphologically normal. Tail defects were the most common (11%), and showed the highest variation between individuals, the values ranging between 4 and 23%. Head abnormalities consisted of large, tapering, and amorphous forms but were not frequent (0.4%), the values ranging between 0 and 1.3%. Midpiece imperfections were found in all the individuals; the mean percentage was 5%, and the range varied between 3 and 9%. Tail plus midpiece was the only multiple abnormality observed, with a mean value of 1.5% and a range between 0 and 8%. The majority of these double defects consisted of a coiled tail together with a coiled midpiece. Mean values for the morphometric parameters characterizing sperm heads were as follows: area 17.2 μm², perimeter 15.2 μm, length 5.8 μm, width 4.0 μm, L/W ratio 1.5, gray‐level 98, ellipticity 0.2, first shape factor 0.9, second shape factor 1.4, and third shape factor 1.1. Overall coefficients of variation for the majority of parameters were below 7%, showing the great homogeneity in the dimensions of cynomolgus sperm heads. Most useful parameters for sperm characterization, according to their low variability, were perimeter, length, width, L/W ratio, and shape factors. Differences in these parameters were, however, observed between monkeys. Am. J. Primatol. 47:105–115, 1999. © 1999 Wiley‐Liss, Inc.     

Development of the definitive kidney in the cynomolgus monkey (Macaca fascicularis)

Abstract: Formation of the definitive kidney in Macaca fascicularis embryos was investigated using light and electron microscopy. Appearance of the definitive kidney at stage 14 was indicated by the ureteric bud invading the metanephrogenic blastema. Glomerular capillaries originate from the connective tissue that surrounds the developing renal vesicle. At 46–100 days gestational age the more developed glomeruli show thinning of the capillary endothelium, thickening of the basal membrane, and presence of pedicels, suggesting a capability of renal function.     

Metabolism and pharmacokinetics of progesterone in the cynomolgus monkey (Macaca fascicularis)

[4-14C]Progesterone was administered to two cycling female monkeys during the luteal phase of the cycle, and blood and urine were sampled over a 24 h period. Progesterone had a volume of distribution of 1.75 +/- 0.3 L/kg, and a plasma elimination clearance of 0.06 +/- 0.03 L/kg/min. In comparison to the human, plasma progesterone binding was greater and progesterone clearance was slower in the cynomolgus monkey. The major unconjugated metabolite in plasma was 20 alpha-hydroxy-4-pregnen-3-one. In urine 6.2% of 14C-steroids were unconjugated, 2.3% of which were [14C]progesterone. Thin-layer chromatography (TLC) of conjugated metabolites in urine revealed that 24% had the mobility of sulfates, 19% that of glucuronides, and 52% were more polar. After hydrolysis of conjugates, a major fraction chromatographed with pregnanediol. However, despite evidence for the presence of a 20 alpha-hydroxyl group, none of the pregnanediol isomers could be identified among these 14C-steroids. Nevertheless, over 80% of urinary metabolites had sufficient analogy to pregnanediol to bind to an antiserum specific for ring D and the C-17 side-chain of pregnanediol.     

The innervation of the myometrium of the cynomolgus monkey (Macaca fascicularis)

Summary The autonomic innervation of the myometrium of Macaca fascicularis consists of bundles of unmyelinated nerve fibres running between the smooth muscle cells, and is therefore considered to be of the fascicular (= unitary) type. Close contacts between nerve fibres and smooth muscle fibres were not found. Modification of the chromaffin method according to Tranzer and Richards made it possible to visualize the heterogeneity of the nerve fibres in a single bundle. The following fibre types were found to coexist: (1) noradrenergic fibres containing synaptic vesicles with a dense granule, (2) cholinergic fibres containing empty synaptic vesicles, and (3) non-adrenergic noncholinergic (NANC) fibres containing only or predominantly large dense-cored vesicles, which do not react with this method. Noradrenergic fibres are the most numerous (around 60%), followed by NANC fibres (30%) and cholinergic elements (around 10%). The distribution of these three types is similar in the cervix, the isthmus and the body of the uterus in pregnant and non-pregnant females.     

Cutaneous melanoma with metastasis in a cynomolgus monkey (Macaca fascicularis)

Background  A 3.3-year-old-male cynomolgus macaque ( Macaca fascicularis ) showed a focally extensive soft, dark, discoid dermal mass, 0.5 cm in diameter, on the dorsal surface of the right hind foot, over the fourth and fifth metatarsal bones.
Methods and results  Microscopic examination revealed a cutaneous melanoma with local lymphatic invasion, characterized by neoplastic melanocytes within the subcapsular sinus of popliteal and inguinal lymph nodes. The diagnosis was confirmed by immunohistochemistry and transmission electron microscopy.
Conclusions  To our knowledge, this is the first documented case of melanoma in a cynomolgus monkey.     

Isolation and culture of hepatocytes from the cynomolgus monkey (Macaca fascicularis)

Summary Isolation and culture techniques for hepatocytes from whole livers of the cynomolgus monkey,Macaca fascicularis, are described. Hepatocytes were isolated by two-step perfusion of livers, using collagenase with hyaluronidase; fructose and trypsin inhibitor were included to reduce cell loss. Yields from a single liver average 4×10⁹ cells with viabilities of 90.8±5.7%. Cells, plated on collagen substrates, were assessed for changes in morphology and various marker enzyme activities over a period of 7 d in culture. Cells exhibited a morphology similar to that observed for this species in vivo; little change in attached and spread cells was observed over the length of time monitored. Enzyme activities for catalase, succinate dehydrogenase, and tyrosine aminotransferase were observed to decrease significantly (though considerable activity remained), whereas acid phosphatase and 5′-nucleotide phosphodiesterase remained unchange. Activity of cytochrome P-450 reductase was observed to increase slightly for the first 2 d, then decrease to about 60% of initial levels. Activity of α-mannosidase was stable for 4 d but was observed to be increased at Day 7. Cells were observed to retain metabolic responsiveness demonstrated by glucose production by both gluconeogenesis and glycogenolysis in response to glucagon stimulation. The monkey hepatocytes obtained by methods described here thus retain hepatocellular morphology and activity through at least 1 wk in culture without medium or culture modification.     

Study of cynomolgus monkey (Macaca fascicularis) DRA polymorphism in four populations

To describe the polymorphism of the DRA gene in Macaca fascicularis, we have studied 141 animals either at cDNA level (78 animals from Mauritius, the Philippines, and Vietnam) or genomic level (63 animals from the Philippines, Indonesia, and Vietnam). In total, we characterized 22 cDNA DRA alleles, 13 of which had not been described until now. In the Mauritius population, we confirmed the presence of three DRA alleles. In the Philippine and Vietnam populations, we observed 11 and 14 DRA alleles, respectively. Only two alleles were present in all three populations. All DRA alleles but one differ from the consensus sequence by one to three mutations, most being synonymous; so, only seven DR alpha proteins were deduced from the 22 cDNA alleles. One DRA cDNA allele, Mafa-DRA*02010101, differs from all other alleles by 11 to 14 mutations of which only four are non-synonymous. The two amino acid changes inside the peptide groove of Mafa-DRA*02010101 are highly conservative. The very low proportion of non-synonymous/synonymous mutations is compatible with a purifying selection which is comparable to all previous observations concerning the evolution of the DRA gene in mammals. Homologues of the allele Mafa-DRA*02010101 are also found in two other Asian macaques (Macaca mulatta and Macaca nemestrina). The forces able to maintain this highly divergent allele in three different macaque species remain hypothetical.     

Successful artificial insemination for indoor breeding in the Japanese monkey (Macaca fuscata) and the cynomolgus monkey (Macaca fascicularis)

Methods of artificial insemination (AI) for indoor breeding in the Japanese monkey and the Cynomolgus monkey were investigated. For the Japanese monkey AI was carried out in six females during the winter mating season and in six females during the summer non-mating season. During the mating season, semen was inseminated near ovulation time in natural menstrual cycles. In the mating season study, three females inseminated at the uterine cavity became pregnant. Three inseminated at the cervical canal failed to become pregnant. For the non-mating season study, ovulation was induced artificially by PMSG and hCG and AI was carried out near the induced ovulation time. In the non-mating season, no animals became pregnant. Of four Cynomolgus monkeys used, pregnancy occurred in two animals inseminated near ovulation time in natural menstrual cycles. AI occurred at the uterine cavity in one and cervical canal in the other. In both species ovulation was verified by laparoscopy. Semen was collected by penile electro-stimulation then diluted to 2.5 to 5.0×10⁷/ml with Whitten's medium. Diluted semen of 0.2l was inseminated at the uterine cavity or cervical canal. Our results indicate the usefulness of vaginal AI as a method of artificial indoor breeding.     

Squamous cell carcinoma with metastasis in a cynomolgus monkey (Macaca fascicularis)

A squamous cell carcinoma of the vulva with metastases to the inguinal lymph nodes and lung occurred in a female cynomolgus monkey (Maccaca fascicularis). The primary tumor was a pedunculated mass at the mucocutaneous junction of the left labium anterior to the clitoris.     

Spontaneously occurring congenital polycystic kidney in a cynomolgus monkey (Macaca fascicularis)

Congenital polycystic kidney disease was diagnosed at necropsy in a stillborn male cynomolgus monkey (Macaca fascicularis). This case was very similar to infantile polycystic kidney disease in man and the rhesus monkey, except that no increase in number of intrahepatic bile ducts was observed.     

Comparison of casein of cynomolgus monkey (Macaca fascicularis) with human casein

Casein of cynomolgus monkey was compared with those from human and bovine milk. Cynomolgus monkey casein showed similar electrophoretical patterns to those of human casein on Disc- and SDS-electrophoresis. It consisted of beta- and kappa-casein-like components. The component corresponding to bovine alpha s1-casein was not detected. The beta-casein-like fraction of cynomolgus monkey showed 9 bands on Disc-PAGE. These were suggested to be the same protein binding different levels of phosphorus by dephosphorylation experiment using an acid phosphatase. The kappa-casein-like component of cynomolgus monkey was highly glycosylated (about 50% carbohydrate) similarly as human kappa-casein and the constituent carbohydrates were same as those detected in human kappa-casein (galactose, fucose, N-acetylgalactosamine, N-acetylglucosamine, and sialic acid). Amino acid composition of cynomolgus monkey kappa-casein bore a resemblance to those of both human and bovine kappa-caseins. Amino acid composition of cynomolgus monkey beta-casein was also similar to those of human and bovine beta-caseins.     

Comparative studies with six extenders for sperm cryopreservation in the cynomolgus monkey (Macaca fascicularis) and rhesus monkey (Macaca mulatta)

Ejaculated spermatozoa from cynomolgus monkeys and rhesus monkeys were frozen in straws with six different extenders (TTE, DM, mDM, LG-DM, G-DM, and TCG) containing glycerol. Sperm motility and head membrane and acrosomal integrity were evaluated after freezing and thawing, and the cryoprotective effects were compared among the extenders and the two species studied. The results showed that sperm motility and motility recovery with the six extenders were comparable for the cynomolgus and rhesus monkeys. There was no significant difference in sperm motility and head membrane integrity among the six extenders in either the cynomolgus or rhesus monkeys (P>0.05). However, a slightly but statistically lower percentage of acrosomal integrity was found with TCG in both species compared to the other extenders (P<0.05). These findings demonstrate that TTE, DM, mDM, LG-DM, G-DM, and TCG are equally suitable extenders for the cryopreservation of spermatozoa from cynomolgus and rhesus monkeys.