Dietary restriction and aging: the initiation of a primate study.

Juvenile (1 yr) and adult (3-5 yr) male rhesus monkeys (Macaca mulatta) and juvenile (1-4 yr) and adult (5-10 yr) male squirrel monkeys (Saimiri sciureus) were fed a diet at or near ad libitum levels based on recommended caloric intake for age and body weight or fed 30% less of the same diet with this restriction gradually introduced over a 3-mo period. Analysis of body weights among these respective control and experimental groups from the first year of the study indicated that the monkeys undergoing dietary restriction were gaining weight at a markedly slower rate compared to control values. Actual food intake among diet-restricted groups had been reduced 22-24% below control levels. Periodic analysis of hematology and blood chemistry measurements over the first year of the study detected few significant differences between control and experimental groups to indicate that diet restriction was not detrimental to general health. When values obtained from hematology and blood chemistry measurements of juvenile and adult groups (control and experimental groups combined) were compared to ad libitum fed old monkeys from each species (greater than 18 yr for rhesus; greater than 10 yr for squirrel monkeys), many significant age differences were noted. Among the largest and most consistent findings in both species were age-related decreases in concentrations of lymphocytes, serum glutamic oxalacetic transaminase, serum glutamic pyruvic transaminase, alkaline phosphatase, and phosphates as well as the albumin/globulin ratio and the blood urea nitrogen/creatinine ratio. Age-related increases in serum globulin and creatinine concentrations were also found. These parameters as well as many others being implemented in the study will be monitored further to determine if diet restriction affects the rate of development as well as aging as observed in numerous rodent studies applying such nutritional manipulations.

Differences in mineral metabolism among nonhuman primates receiving diets with only vitamin D3 or only vitamin D2.

We tested for differences in aspects of mineral metabolism during the administration of diets with only vitamin D3 or only vitamin D2 in four nonhuman anthropoid primate species [two catarrhini, Macaca fascicularis (crab-eating macaque) and Macaca mulatta (rhesus macaque), and two platyrrhini, Saimiri sciureus (squirrel monkey) and Aotus vociferans (night monkey)]. All four species maintained approximately 2- to 3-fold higher serum 25-hydroxyvitamin D (25OHD) level while receiving vitamin D3 than while receiving similar amounts of vitamin D2. Serum 25OHD in M. mulatta receiving the standard primate dietary supplement of vitamin D3 was high enough (360 +/- 60 vs. 70 +/- 25 nM in vitamin D-supplemented humans; P less than 0.0001) to suggest that this widely used level of vitamin D3 supplementation is excessive for some M. mulatta. Serum 24,25-dihydroxyvitamin D [24,25-(OH)2D] in A. vociferans was uniquely high [P less than 0.01; species mean, 19 +/- 5, 95 +/- 12, and 27 +/- 5 nM in groups receiving diets with 1.5 IU vitamin D3/g, 6.6 IU vitamin D3/g, and 15 IU vitamin D2/g, respectively; mean 24,25-(OH)2D from the other three species pooled across three diets was 7 +/- 5 nM]. We confirmed relative resistance to 1,25-(OH)2D in S. sciureus, manifested by osteomalacia and moderately high serum 1,25-(OH)2D. Serum 1,25-(OH)2D in S. sciureus increased 4-fold (P less than 0.05) when the precursor in serum was changed from 250HD3 to 250HD2, suggesting that this species shows more severe resistance to 1,25-(OH)2D2 than to 1,25-(OH)2D3. In conclusion, we found many differences in vitamin D metabolism among four nonhuman anthropoid primate species. The striking feature in A. vociferans (high, 24,25-(OH)2D without high 25OHD in serum independent of whether diet contained only vitamin D3 or only vitamin D2) should allow determination of whether 24,25-(OH)2D functions as a unique agonist or an inactive metabolite in this species.

Selected biohazards of naturally infected nonhuman primates.

The nonhuman primate is susceptible to a great number of microbiological hazards. Two groups of organisms, campylobacter and atypical mycobacteria, are important as examples of naturally occurring primate biohazards. This paper attempts to define these organism groups and their potential for problems in primates housed in natural environments. Efficient, continuous, and specific husbandry and veterinary management techniques must be employed to avoid potential disease outbreaks.

Zoonoses acquired from pet primates.

Laws regulating the importation of primates have drastically reduced the number of primates seen as pets and, thus, the hazard both to the potential owner and veterinarian. Active disease and latent carrier states in primates potentially have severe consequences for the contact person. This potential for human transmission makes it imperative that medical and veterinary professionals collaborate to educate the public on the danger of the primate as a pet.

Uterine estrogen and progesterone receptors in an estrogen- and progesterone- "resistant" primate.

The squirrel monkey, a New World primate, has elevated plasma estradiol and progesterone concentrations compared to those in the cynomolgus macaque, an Old World primate. We previously reported that uterine progesterone receptor concentrations examined in ovariectomized squirrel monkeys 2 days after estrogen treatment were about one eighth those in identically treated cynomolgus macaques. To examine this in greater detail, we gave estradiol (10 micrograms/kg X day) to ovariectomized squirrel and cynomolgus monkeys for various lengths of time (0, 2, 4, 7, and 14 days), followed by measurement of uterine estrogen and progesterone receptors and assessment of endometrial histology (including glycogen and peroxidase strains), vaginal histology, and cytology. Endometrial and vaginal morphologies showed adequate estrogen effects, as did glycogen and peroxidase stains. Two days of treatment were sufficient to induce both estrogen and progesterone receptors to maximal binding of [3H]moxestrol and [3H]R5020, respectively, in both species. Squirrel monkeys had about one third and one eighth the estrogen and progesterone uterine receptor concentrations, respectively, of cynomolgus monkeys. Receptor affinities in both species were similar. Neither [3H]moxestrol nor [3H]R5020 bound to uterine cytosols from untreated monkeys. We conclude that the increased plasma concentrations of estradiol and progesterone in the squirrel monkey compensate for the decreased estrogen and progesterone receptors in this species.

Flexible fiberoptic proctoscopy compared with fecal examination techniques for diagnosis of Prosthenorchis infection in squirrel monkeys (Saimiri sciureus).

Using flexible fiberoptic proctoscopy, diagnosis of Prosthenorchis infection in 17 squirrel monkeys (Saimiri sciureus) was correct 100% of the time. Fecal examination by formalin-ether sedimentation and sodium nitrate flotation were 68% and 10% diagnostically correct, respectively.

XX/"XO" sex determination system in a population of Peruvian owl monkey, Aotus.

The chromosome complement of a group of owl monkeys with typical pelagic features characteristic of Aotus inhabiting the upper Amazonian region in South America was analyzed by various band techniques. A diploid chromosome number of 2n = 52 is reconfirmed in the females. A Y-autosome translocation resulting in a complement of 2n = 51 in the males constitutes a unique XX/"XO" sex chromosome system in this population. Karotypic comparison of this Peruvian Aotus (2n - 52 female/51 male) with the Bolivian Aotus (2n = 50 female/49 male) shows the existence of a large degree of analogy of chromosome banding. However, complicated inter- and intra-karyotypic differences between the two chromosome races can be depicted, and substantiates our postulation that the owl monkey is an evolutionary actively diverging species.

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.

Mycobacterium scrofulaceum infection in Erythrocebus patas monkeys.

Mycobacterium scrofulaceum was cultured from two of seven tuberculin reactors in a group of 12 Erythrocebus patas monkeys. One monkey reacted atypically to 0.1 ml of 2.5 mg veterinary tuberculin after having shown no reaction to four previous tests administered at 2-week intervals. The reaction consisted of edema with no induration or erythema at 24 hours and was completely dissipated at 36 hours. Responses to additional tests using veterinary tuberculin (2.5 mg) and Mycobacterium bovis purified protein derivative (1.1 mg) ranged from negative to slightly edematous. Radiographs were suggestive of pulmonary tuberculosis. Extensive granulomas were observed in the lungs, liver and spleen at necropsy. Mycobacterium scrofulaceum was isolated from lung and liver granulomas in this animal and from lung granulomas in another. The atypical skin hypersensitivity and organism isolation from multiple organs suggested Mycobacterium scrofulaceum as the etiologic agent in these animals. Reactions of six other Erythrocebus patas to veterinary tuberculin (2.5 mg) ranged from edematous to indurated.

The effect of dietary crude fiber levels on rhesus monkeys during quarantine.

A study was conducted to determine the effect of dietary crude fiber level on intestinal disorders in the feral rheusus monkey (Macaca mulatta) during the first 60 days of the quarantine period. Three experimental baked diets containing 2.4%, 7.0%, and 9.8% crude fiber and a commercially extruded diet containing 2.2% crude fiber were fed during the study. The morbidity rate of intestinal disorders at the 7% crude fiber level was 1.4%, which was significantly less (p less than 0.05) than the 11.1%, 12.5%, and 20.8% morbidity for the monkeys fed the diets containing 2.4%, 9.8%, and 2.2% crude fiber, respectively. Monkeys fed the 7% crude fiber diet had a mean number of treatment days for intestinal disorders per monkey of 0.014, which was significantly lower (p less than 0.05) than the 0.9, 0.5, and 1.4 days for those fed the 2.4%, 9.8%, and 2.2% fiber diets, respectively.

Hematologic, biochemical, and physiologic indices of the sacred baboon (Papio hamadryas).

Hematologic, biochemical, and physiologic indices for a recently imported group of sacred baboons, Papio hamadryas, were studied over a 6-week period. Hematologic values were in agreement with results recorded for other species of baboons. Blood biochemical data were consistent with findings previously reported for other baboons and for man except that alkaline phosphatase levels were higher than previously for other baboons but similar to those reported for man; lactic dehydrogenase levels were higher than for man but lower than for other baboons; cholesterol levels were within the range for baboons but lower than for man; and creatinine and uric acid levels were lower and amylase levels were higher than those for man. Temperature and respiration and pulse rates were in agreement with those reported for other baboons.

A natural case of Schistosoma mansoni in the chimpanzee (Pan troglodytes versus).

A spontaneous infection with Schistosoma mansoni was found in a chimpanzee (Pan troglodytes versus) recently imported from Sierra Leone, Africa. Clinical signs consisted of anemia, liver enlargement, bronchial rales, and emaciation. The primary gross pathologic lesions included a fibrotic firm nodular liver and pulmonary edema and consolidation. Histopathologic examination revealed changes similar to the experimental syndrome of Manson's schistosomiasis in the chimpanzee. The diagnosis was confirmed by the presence of the eggs and larvae of Schistosoma mansoni.