Simian immunodeficiency virus infections in vervet monkeys (Clorocebus aethiops) at an Australian zoo

A number of monkey species, including African green monkeys and African vervet monkeys (Chlorocebus aethiops), are frequently infected in the wild and in captivity with a Simian immunodeficiency virus strain, SIVagm, a primate lentivirus. Up to 50% of African green monkeys are estimated to be infected with SIVagm. SIV strains are very closely related to HIV-2 strains, which are a cause of AIDS in humans, predominantly in western Africa, although cases in Australia have also been reported. It is generally thought that SIV is non-pathogenic in several natural hosts, including African green monkeys. Nevertheless many SIV strains induce a profound immunodeficiency virtually identical to HIV-1 induced AIDS in humans when administered to Asian macaque species such as rhesus (Macaca mulatta) or pigtailed macaques (M nemestrina). SIV infection of Asian macaque species is frequently employed as an animal model for AIDS vaccine studies. In November 1996 a group of 10 African vervet monkeys were imported from the USA for display at Victoria's Open Range Zoo in Werribee. Two animals in this group of monkeys later developed a fatal gastroenteric illness. These diagnoses led us to initiate SIV testing of the colony.     

Serum procollagen type III peptide levels in normal rhesus monkeys

Serum levels of the amino-terminal peptide of Type III procollagen (P-III-P) were assayed by radioimmunoassay in 48 Rhesus monkeys from 0.7 to 26.4 years of age. Serum P-III-P levels in ten juvenile monkeys (0.7-4.7 yrs.) were significantly higher (84.5 +/- 66.2 ng/ml, p = 0.05) and ranged from 29.6 to 238.0 ng/ml as compared with 38 monkeys over 5 years of age (21.7 - 9.4 ng/ml), which ranged from 8.5 to 55.5 ng/ml. No significant differences in serum P-III-P levels were observed between any age groups over 5 years of age (5-10, 10-15, 15-20, and > 20) or between male and female monkeys within any age category.     

B型超声显像技术在实验猕猴繁殖中的应用

采用MEDISON SA-600型超声实时显像仪,以妊娠囊作为主要的判断依据,对658只配种实验猕猴进行早期妊娠诊断的探索。结果表明:妊娠15d诊断准确率为95.5%,20d诊断准确率为100%。同时对猕猴妊娠各期B超影像的特征及猕猴检测的操作特点进行论述。     

A comparative study of natural killer cell activity, lymphoproliferation, and cell phenotypes in nonhuman primates.

Three different species of nonhuman primates (baboons [Papio hamadryas], rhesus monkeys [Macaca mulatta], and African green monkeys [Cercopithecus aethiops]) were evaluated for their natural killer cell activity, and for the ability of their peripheral blood mononuclear cells to proliferate in response to known mitogens (concanavalin A, phytohemagglutinin, and pokeweed mitogen) and to react with a panel of mouse monoclonal antibodies directed against human leukocyte surface antigens. Rhesus monkeys displayed the highest natural killer cell cytotoxic activity (185.7 +/- 33 lytic units) compared with those of baboons (83.8 +/- 19 lytic units) and of African green monkeys from West Africa (39.08 +/- 8 lytic units) and from the Caribbean basin (37.9 +/- 9 lytic units). No correlation was observed between the natural killer cell cytotoxic activity and the percentage of CD16+ natural killer cells among the three species studied. High spontaneous proliferative capacity was observed in African green monkeys obtained from West Africa compared with those of the other species studied. Although no significant differences were noted in T and B cell mitogen-induced in vitro proliferation, baboon mononuclear cells were less responsive to concanavalin A (stimulation index of 16 +/- 3 [mean +/- standard error of mean]) than to phytohemagglutinin (stimulation index of 47 +/- 12). However, rhesus and African green monkey cells proliferated more efficiently in response to concanavalin A. Unlike in human beings where the ratio between helper-inducer (CD4+) and cytotoxic-suppressor (CD8+) T-lymphocytes is generally greater than 1, the CD4+/CD8+ ratios in baboons and rhesus and African green monkeys were 0.58, 0.69, and 0.35, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Astrocytic responses in the lateral geniculate nucleus of monkeys with experimental glaucoma

Objective To investigate the responses of lateral geniculate nucleus (LGN) astrocytes to experimental glaucoma in monkeys. Animal studied Rhesus monkeys (Macaca mulatta). Procedures Unilateral chronic elevation of intraocular pressure (IOP) was induced in six rhesus monkeys by laser photocoagulation of the trabecular meshwork. Four normal monkeys were used as controls. Immunohistochemistry with antibodies to glial fibrillary acidic protein (GFAP), S100β and parvalbumin was used to specifically label astrocytes and neurons in the LGN. The relative immunointensity (RI) of GFAP was defined as the ratio of intensity between each region of interest to a reference field and compared between the experimental and control groups as a function of percentage optic nerve fiber loss. Ultrastructural changes of LGN astrocytes were examined by transmission electron microscopy. Results An increase in GFAP and S100β immunoreactivity was observed in the LGN layers receiving projections from the experimental glaucoma eyes. Quantitative analysis revealed that the RI of GFAP in both the magnocellular and parvocellular layers connected to the glaucomatous eyes increased in a linear fashion with increasing optic nerve fiber loss. Compared to controls, the RI of GFAP was also moderately elevated in LGN layers connected to the fellow nonglaucomatous eyes. Ultrastructurally, accumulation of glial filaments that occurred throughout the perikaryon and extended into the process in reactive astrocytes was observed in LGN layers of glaucomatous monkeys. Conclusions Reactive astrogliosis occurs in the magnocellular and parvocellular LGN layers of monkeys with unilateral glaucoma. Astrocytes may play an important role in the regulation of LGN microenvironment in glaucoma.     

Effects of ketamine hydrochloride on serum biochemical and hematologic variables in rhesus monkeys (Macaca mulatta)

Serum biochemical and hematologic values were obtained from Rhesus monkeys (Macaca mulatta) before and 15 minutes after intramuscular injection with ketamine hydrochloride (5-10 mg/kg). A 345% increase in serum creatine kinase activity 15 minutes after ketamine administration was attributed to muscle damage caused by the injection. Decreases in erythrocyte count, hemoglobin, hematocrit, total leukocyte count, lymphocyte count, and the serum concentrations of glucose, total protein, albumin, and other serum analytes were all attributed to the reversal (by ketamine) of the excitement or "alarm reaction" associated with physical restraint. The decrease in circulating erythrocytes and lymphocytes indicated a redistribution of these cells from the circulating blood to the spleen and extravascular sites, respectively. Decreases in concentrations of total protein, albumin, and several other serum analytes suggested an influx of fluid into the vascular space. The decrease in glucose may also reflect the reversal of an epinephrine-induced hyperglycemia in the excited awake monkey. These alterations should be considered when designing studies and interpreting data for Rhesus monkeys.     

Isolation and identification of a South China strain of Plasmodium inui from Macaca fascicularis

Southeast Asian macaques are hosts of a number of Plasmodium infections, some of which are transmittable to humans. During examination of blood films of five wild-caught long-tailed macaques Macaca fascicularis from South China, malaria infection was detected in one of the monkeys. In order to isolate this parasite for identification and characterization, we experimentally passed this parasite through both Assamese (M. assamensis) and rhesus (M. mulatta) monkeys by intravenous injection of infected blood. This parasite morphologically resembled Plasmodium inui, and had a typical 72 h quartan periodicity. This parasite was infective to Anopheles dirus mosquitoes, and salivary gland sporozoites appeared 13 days post feeding. Feeding by 20 infected An. dirus mosquitoes on another Assamese monkey produced infection with a prepatent period of 8 days. Molecular analysis of the small subunit rRNA genes and the mitochondrial genome confirmed this parasite as an isolate of P. inui. In spleen-intact macaques, the infection had a protracted duration with parasites being detected during the rearing of the infected monkeys for over two years. In summary, this study identified a P. inui isolate and successfully passed this parasite through Assamese monkeys by both intravenous inoculation and mosquito transmission.     

Fundus pigment distribution in rhesus monkeys

There is growing evidence for an interaction among fundus pigmentation, character, geography and the function and structure of the outer retina. We examined three inbred groups of rhesus macaques (132 eyes) including all ages. One was a smaller (18 eyes) group. Coat colors were variations of brown-tan however, the smaller group had lighter 'golden' coats and colors. Fundus images were classified for pigmentation and its geographic distribution. In golden-coated animals there was bias toward nasal fundus hypopigmentation with the optic disk as a watershed demarcation zone, which extended in the superior-inferior direction. Temporal fundus hypopigmentation did not occur in the absence of nasal hypopigmentation. More common, darker coated samples showed a characteristic diffuse fundus pigmentation. There was no evidence for albinism or large variations in macular pigmentation. Rhesus monkeys can exhibit geographically controlled genetic development of fundus pigmentation. Hypopigmentation provides for access to the choroidal infrastructure.     

Anaesthetic and cardiorespiratory effects of ketamine plus dexmedetomidine for chemical restraint in black capuchin monkeys (Sapajus nigritus)

AIMS: To evaluate the quality of anaesthesia and cardiorespiratory effects of ketamine and two doses of dexmedetomidine in captive black capuchin monkeys (Sapajus nigritus) undergoing routine clinical examination.

METHODS: Twenty-four animals undergoing routine clinical examination were enrolled in the study. Animals were briefly physically restrained and examined to ensure no obvious illness was present and that they were healthy. Monkeys were randomly allocated to two groups (n=12 per group) and then treated with a combination of I/M 7.5?mg/kg ketamine and either 30?µg/kg or 50?µg/kg dexmedetomidine (Dex30 or Dex50 groups, respectively). Interval to onset and duration of anaesthesia were recorded, and the quality of induction of anaesthesia and recovery were subjectively evaluated. Heart rate, respiratory rate, systolic arterial pressure (SAP), rectal temperature, degree of sedation, analgesia, muscle relaxation and response to auditory stimulus were measured every 5 minutes from onset of anaesthesia until recovery.

RESULTS: The mean interval to onset of anaesthesia was 7.3 (SD 6.6) and 9.1 (SD 5.0) minutes for the Dex30 and Dex50 groups, respectively (p=0.208). Mean duration of anaesthesia was longer for monkeys in the Dex50 (85.5 (SD 15.3) minutes) compared to those in Dex30 (63.9 (SD 16.4) minutes) group (p=0.003). Induction was considered excellent in 23/24 animals, and recovery was excellent in all animals. Heart rate, respiratory rate and body temperature decreased in both groups when compared to baseline, with no differences between groups. No differences between groups were found for assessments of sedation, analgesia, muscle relaxation or response to auditory stimulus.

CONCLUSION AND CLINICAL RELEVANCE: Administration of ketamine and dexmedetomidine at the two doses produced adequate, dose-dependent chemical restraint, with excellent induction and recovery, and minimal clinically significant cardiorespiratory effects in captive capuchin monkeys. Due to the occurrence of arrhythmias, electrocardiographic monitoring is recommended when this combination is used. The administration of higher doses of dexmedetomidine produced longer lasting anaesthesia without further compromise of cardiorespiratory parameters.     

Variations in the immune response to herpesvirus saimiri in squirrel and rhesus monkeys

Humoral and cell-mediated immunity (CMI) to herpesvirus saimiri (HVS), an oncogenic lymphotropic herpesvirus, was studied in squirrel and rhesus monkeys. Natural antibody to HVS was found in five of six squirrel monkeys but there was no evidence of specific CMI directed against HVS. Rhesus monkeys did not show natural antibody or CMI against HVS antigens. Immunization with HVS, however, produced both antibody and specific CMI in the rhesus monkeys, but no CMI developed in the squirrel monkeys. These findings are important in the development of animal models for the treatment of tumors associated with lymphotropic herpesviruses.     

An ontogenic study of the acute inflammatory response in the fetal rhesus monkey. II. The mediation of increased vascular permeability by histamine, compound 48/80 and bradykinin.

Vascular permeability as a function of age was evaluated quantitatively and morphologically in skin of fetal Rhesus monkeys given vasoactive mediators. The response was examined at 90, 120 or 150 days of gestation or at birth and compared to the response of yearling Rhesus monkeys. Skin sites were challenged with histamine, compound 48/80 or bradykinin. Evans' blue and horseradish peroxidase were used as markers of vascular integrity. Evans' blue was quantitated spectrophotometrically. Vascular permeability during fetal life was depressed. Fetal venules and capillaries had poorly formed basement membranes, an abundance of microfilaments within endothelial cells, occasional electron dense endothelial cells and infrequent deposits of extravascular peroxidase.     

An investigation into the use of propofol (Rapinovet®) in long-tailed macaques (Macaca fascicularis)

Propofol, an intravenous (iv) anaesthetic agent, was given to 12 long-tailed macaque monkeys (Macaca fascicularis) that were initially chemically restrained using ketamine hydrochloride. Anaesthesia was induced and maintained using incremental iv injections of propofol at various dose rates. Physiological parameters were monitored during anaesthesia. Five animals were allowed to recover from anaesthesia and their recovery was usually uneventful. At the dose levels investigated there was good muscle relaxation and analgesia and cardiovascular and respiratory functions were adequately maintained. A dose of 10 mg/kg bodyweight gave moderate surgical anaesthesia for between 20 and 40 mins.     

数字减影血管造影定位引导技术在动态采集恒河猴脑脊液中的应用

探索数字减影血管造影(DSA)定位引导技术在恒河猴脑脊液动态采集中的应用。将28只恒河猴随机均分为2组,经左前肢静脉推注30g/L戊巴比妥钠溶液全麻后,常规剔除背部脊柱周围体毛并消毒;试验组在DSA定向引导技术下行腰椎间隙穿刺蛛网膜下腔采集脑脊液,结果14只全部穿刺成功,穿刺后均有脑脊液从穿刺针中流出;对照组直接行腰椎间隙穿刺蛛网膜下腔,8只穿刺成功,6只穿刺失败,后经DSA定位引导技术调整针尖方向与位置,完成穿刺,采集到脑脊液;28只恒河猴穿刺成功后均在DSA定位引导下将硬膜外麻醉导管经蛛网膜下腔至枕大池,置泵于腰背部,通过所置的泵可实现恒河猴在清醒、全生理状态下对脑脊液进行动态多次采集,快速省时,由于采样导管置于枕大池,采集到的脑脊液无色透明、样品质量有保证,易于满足检验需要,具有一定的实用价值。     

Chronic cadmium treatment induces islet B cell injury in ovariectomized cynomolgus monkeys

In an attempt to establish a primate model of chronic cadmium (Cd) toxicosis, we ovariectomized cynomolgus monkeys and treated with CdCl2 by repeated intravenous injections for 13 to 15 months. The animals showed an increase in blood glucose from Month 10 and a decrease in blood insulin at Month 11of the Cd-treatment. Histopathological examination of the Cd-treated animals revealed islet atrophy with reduction in islet number and vacuolation of the islet cells, whereas there was no remarkable change in the acinar cells of the exocrine pancreas. In histomorphometrical examination, insulin-positive areas in the islets were significantly decreased, accompanying a relative increase of glucagon-positive areas. Large amounts of Cd accumulated in the pancreas, and metallothionein (MT), a Cd binding protein, was localized in the islets of Cd-treated animals. The present study demonstrated that the chronic intravenous injection of Cd to cynomolgus monkeys induced the accumulation of the metal in the pancreas, degeneration of islet B cells and the diabetic clinical signs. Therefore the islet B cell is one of the major targets of the chronic Cd poisoning in monkeys.     

实验猕猴早早孕诊断

利用便携式B型超声仪检查诊断实验猕猴早早孕情况。结果表明B超检查妊娠10d、15d、20d猕猴的诊断准确率分别为53.1%（17/32）、76.0%（24/32）、100%（32/32）。     

自发性瘫痪猕猴的血液生化分析

测定分析了四自发性后肢瘫痪猕猴和十例正常猴的三十条项血液生化指标，比较研究了养条件下瘫痪猕猴的血液生化代谢特征。结果表明：瘫痪猕猴的血钙、血锰、血糖和血铁均明显低于正常猕猴（Ｐ＜０．０５）；血清碱性磷酸酶活性也明显高于正常猕猴（Ｐ＜０．０１）；与心、脑血管系统栓塞性病变有关的酶及血脂均与正常猴无显著性差异（Ｐ＞０．０５）；血清免疫球蛋白（ＩｇＧ和ＩｇＡ）及补体（Ｃ３和Ｃ４）均明显高于正常猴（Ｐ＜０     

SLO angiography: arterio-venous filling times in monkey and minipig

Confocal scanning laser ophthalmosocope (cSLO) is a new technique which enables ocular fundus image recording and dynamic retinal angiography to be performed. The ocular fundus image is acquired sequentially, point by point, and is reconstructed on a video monitor at the rate of 25 images per second. The aim of this paper is to evaluate the feasibility of measuring retinal arterio‐venous filling times (AVFT) with a I + Tech cSLO. Three young adult cynomolgus monkeys and three young adult Göttingen minipigs were used as experimental models. All animals were anesthetized using a zolazepam + tiletamine mixture injected intramuscularly; heart rate and rectal temperature were monitored and corneal irrigation was regularly performed. For all subjects, prior to examination, hematocrit and globe axial length were measured. The images were recorded, stabilized and analyzed. The retinal examination consisted of retinal images with 40° field cSLO, retinal fluorescein angiography and arterio‐venous 50% filling time measurements. For each subject all images were easily recorded while keeping the animals in a normally lighted room without having to use any additional optical device. AVFT using an I + Tech cSLO is easily performed in monkeys and minipigs. AVFT measurements in minipigs and monkeys are similar. These results suggest that minipigs can replace monkeys as an experimental species for AVFT investigations.     

Study of retinal microvessels in a Rhesus monkey model of chronic high intraocular pressure

Objective  To investigate the changes in retinal vessels, especially macular capillaries, under high IOP using the Rhesus monkey high IOP model.
Methods  The trabecular meshwork of the adult Rhesus monkey was cauterized by laser to induce increased IOPs with different degrees of damage. The eyeballs were enucleated, and the optic nerves were stained with toluidine blue in semithick slices. Part of the retina was observed under electron microscope, and the rest was stained by the ADPase method. The damage levels of the optic nerve were evaluated by axon count, and the pathological appearance of the macular capillaries were observed.
Results  Five mildly damaged eyes, three moderately damaged eyes and three severely damaged eyes were evaluated. Dense and intact perifoveal vascular rings were observed in all the eyes. The vessels' area percentages, as well as area, perimeter and diameter of the foveal avascular zones, were measured, and no statistically differences were found among different groups ( P -values were 0.269, 0.500, 0.951, and 0.555 separately). The ultra structures of the normal capillaries showed regular tubes and intact basement membranes, while lipoid substances in capillary tubes, swollen mitochondria in endothelial cell bodies, and uneven basement membranes were found in the high IOP-damaged eyes.
Conclusions  Compared with normal eyes, no obvious differences were found in macular microvessels and foveal avascular zones in the Rhesus monkey model of high IOP. However, presence of swollen mitochondria in endothelial cells and lipoid substances in capillary tubes might suggest that high IOP could damage the capillary endothelial cells.     

The influence of Pueraria mirifica herb containing phytoestrogens on the urinary gonadotropin and estradiol levels in aged menopausal monkeys

We investigated a non‐invasive method of specimen collection for determining the changes of reproductive hormones in aged menopausal monkeys after a long‐term feeding of the Thai herb Pueraria mirifica (PM) containing phytoestrogens. Three groups of aged menopausal monkeys (n = three in each group) were fed daily with 10, 100, or 1000 mg of PM for a 90 day treatment period, and fed with distilled water for 30 and 60 days of the pre‐ and post‐treatment periods, respectively. Urine samples were collected for 14 h daily every 5 days and assayed for follicle stimulating hormone (FSH), luteinizing hormone (LH) and estradiol levels. The result showed that monkeys fed with PM 10, PM 100, and PM 1000 had a decrease in urinary FSH levels during the treatment period, followed by a rebound increase during the post‐treatment period. Urinary estradiol levels tended to decrease and fluctuated between 4.28 and 266.71, 2.85–42.27, and 6.24–203.50% of the pre‐treatment levels in those three groups, respectively. Decreases in urinary LH levels could not be observed in all the three groups. These results suggest that FSH could be a candidate marker to detect the estrogenic effects of phytoestrogens in aged menopausal monkeys when changes of urinary hormones need to be used as an indicator.     

Molecular identification and characterization of Mycobacterium avium subspecies paratuberculosis in free living non-human primate (Rhesus macaques) from North India

In recent years, Mycobacterium avium subspecies paratuberculosis (MAP) has emerged as major animal pathogen with significant zoonotic concerns, worldwide. MAP infection is endemic in domestic and wild ruminant population in India. However, information on MAP infection in free ranging animal species and non human primates is limited. Present study aimed to estimate the status of MAP infection in free living Rhesus macaques suffering with multiple clinical conditions (coughing and loose stool). A total of 25 stool samples were collected from six colonies of Rhesus macaques from Mathura region (North India) and screened for the presence of MAP, using microscopic examination and IS900 PCR, directly from stool samples. PCR positive DNA samples were further genotyped using IS1311 PCR-restriction enzyme analysis. Of the 25 stool samples, 10 (40.0%) and 2 (8.0%) were positive for MAP using microscopic examination and direct IS900 PCR, respectively. IS900 PCR positive DNA samples were genotyped as ‘Indian Bison type’, which is a major MAP genotype infecting domestic and wild ruminant species and human beings in India. Prevalence of MAP in Rhesus macaques (Indian monkeys) was moderately high and confirmed interspecies sharing of MAP between domestic livestock and non-human primates. Presence of MAP in non-human primates, support the etiological role of MAP in inflammatory bowel disease patients. Indian monkeys may serve as model for understanding the role of non-human primates in sustenance, transmission and pathogenesis of MAP infection.