Sixty-one weeks after 48 weeks of treatment with fluphenazine decanoate or placebo, 37 socially living Cebus apella monkeys were evaluated for differences in dopaminergic sensitivity by exposure to 0.75 mg/kg, i.m. of amphetamine (AMPH) (indirect agonist) and apomorphine (APOM) (direct agonist). The fluphenazine-treated animals differed (p < or = 0.05) from control animals on some hourly measures of composite behavioral variables (CBVs). Animals exposed to fluphenazine showed a greater decrease in the aggressiveness CBV and a smaller decrease in self- and environment-directed behaviors than placebo animals. CBVs for normal locomotion and directs affiliation showed no significant differences. The fluphenazine-treated group showed greater agonist induction of stereotypic behavior (p < or = 0.01), and larger decreases in prolactin response to AMPH (p < or = 0.05). Our findings indicate that following extended treatment with an antipsychotic there is increased sensitivity to dopamine, as evidenced by stereotypies and possibly hypophyseal responsiveness.

This study examined sexual and other social behavior in relation to menstrual cycle phase in four mixed-sex social groups of Cebus apella. Groups consisted of two adult males and either six or nine adult females. Menstrual cycles of high (rank 1-2) and low (rank 3-7) dominance-rank females from each group were monitored via vaginal swabs, and correlated with data collected from ongoing behavioral observations. Only cycles bounded by positive detection of menstrual blood were included in this analysis (n = 15 females, 182 cycles; mean ± s.d., cycle length = 20.8 ± 1.2 days). Rates of copulation and female solicitation of males varied significantly with cycle phase, with highest rates at midcycle. While total rates of solicitation and copulation did not vary with female dominance rank, copulation rates with the dominant male were significantly greater for high ranking females than for low ranking ones. Variance observed in affiliative and agonistic behaviors, including those with males, was attributable to female rank rather than cycle phase. Females and males were also observed attempting to interfere with copulations of lower ranking same-sex individuals. Although further study, particularly of wild populations, is needed, these results indicate that female-female reproductive competition should be included as a component of the capuchin breeding system. As in other primate species, both social and hormone-related factors influence the sexual behavior of Cebus apella. © 1995 Wiley-Liss, Inc.

Nonhuman primates can be used to develop models that use complex behaviors to evaluate the toxicity of pharmaceutical and other products, Primate functional observational batteries (FOBs) can be designed to resemble those used in rodent tests, although they need not focus on simple conditioned motor responses as small mammal FOBs frequently do. Primates generally are not suitable for use in most (first-tier) neurotoxic screening tests for both practical and scientific reasons, as well as for ethical ones. With regard to practicality factors of cost, animal availability, husbandry, and housing, and observer labor intensity, all increase with the use of primates. With regard to research design, accumulating evidence indicates that primate pharmacologic responsivity is affected by social variables in such a way that group-housed animals provide more realistic (valid) models of human neurobehavioral and disease processes in general. This further complicates primate use and behavioral measurement and evaluation. Data from a long-term study of semipermanant behavioral and electrophysiologic alterations brought about by extended exposure to a psychoactive medication are presented in order to illustrate these points and to indicate how such measures can be useful, and at times indispensable, in second-tier evaluation.

The average auditory event-related potential (AAEP) to nonmeaningful stimuli has maximum vertex negative and positive amplitudes at about 100 and 200 msec, respectively. This “vertex potential” was studied under different arousal conditions in 75 normal men and 30 chronic schizophrenic subjects using the average event-related vector electro-encephalogram (AEVE) and the AAEP. The AEVE shows the path, in time, of the event-related electric field vector. To produce intramodal arousal, normal subjects also had EEG recordings made during the random sounding of a loud bell. AAEPs and AEVEs were calculated for spontaneous changes in arousal, as indicated by EEG delta band power. Bell arousal of the normal subjects increased the AAEP and AEVE measures of vertex potential maxima, thus increasing the existing differences between normals and schizophrenics. Analysis of the AEVE path indicates that arousal increased the electric field intensity, but probably did not alter, within the first 250 msec, the spatial distribution of the cortical EEG generators. After 250 msec, a reorganization of generators was indicated for the three groups. Schizophrenics differed from normals in the decreased maximum intensity of the vertex negative electric field, which was indicated by both the AEVE and AAEP.

This paper describes the design and use of an observation and recording system in which data on behavioral patterns exhibited by socially-living primates are recorded as present or absent within recurring units of time. Behavioral observations and initial editing are carried out on-line on a microcomputer. The checklist of observed behavious is open-ended and modifiable, as required by the selection of subject species and by experimental goals. Summary statistical reports are available immediately after data entry has been completed. Further editing and organization of data files take plance when data are transferred to a large computer. The virtues of this system are its ease of use by observers who can be trained rapidly, its cost-effectiveness, and its ability to record simultaneously a larger number of behaviors than other systems usually can. Included are examples of data-analytic programs which are executed after data have been transferred to a large computer.

Dominance ranks were determined for each of 13 free-ranging stumptail macaques on the basis of competitive food tests. Detailed daily observations of the social behavior and inter-animal spatial proximity relationships were made on each of the animals for 8 weeks. The dominance ranks were correlated with rankings for the proximity data and total scores per animal for the behavioral variables Grooming, Groomed By, Huddling, Touching, and a composite of these four, Affiliation. Significantly high positive correlations were found between the dominance ranks and the ranks for the variables Groomed By, overall Affiliation and Pair Proximity Scores.

A seven-year-old male gibbon ape (Hylobates lar) with malignant lymphoma and leukemia was obtained from a colony in Bermuda. Tissues obtained at necropsy were infiltrated with tumor cells to varying degrees, the most extensively involved being the kidneys, ureters, liver, lymph nodes, heart, salivary glands, and mesentery. These cells showed typical lymphoblast morphology. Type-C virus particles were abundant in the plasma and were detectable in all tissues tested. Intracytoplasmic virus was seen in some nonleukemic parenchymal cells. However, budding virus particles were observed only from the leukemic peripheral blood lymphoblasts. Tissue extracts contained viral p30, reverse transcriptase, viral RNA, and proviral DNA in amounts which generally correlated with the degree of leukemic cell infiltration. Viral markers were particularly abundant in tissue from the region of the oral cavity. Proviral DNA was found in all tissues except muscle and brain, which contained little or no leukemic cell infiltration. Replicating virus was transmitted to heterologous cells in tissue culture from many tissues, including muscle and brain. This virus, called GaLVH was classified as a member of the gibbon ape leukemia virus-simian sarcoma (simian sarcoma-associated) virus group by comparative tests of the antigenic relatedness of p30 and reverse transcriptase, and by nucleotide sequence homology of RNA from this virus and from other members of this group. These results: (a) highlight the extraordinary replication of this type of virus in gibbons; (b) further implicate this virus group in the etiology of spontaneous gibbon ape leukemia; (c) suggest that the oral route is a likely mode of virus transmission; and (d) fail to provide evidence for a genetic reservoir of virus outside of the tumor cells.