Paulo Henrique Gomes de Castro

Uterine evaluation and gestation diagnosis in owl monkey (Aotus azarai infulatus) using the B mode ultrasound

Background  Gynecological and obstetrical ultrasonography has become an indispensable tool in the routine management, health evaluation and research on captive non‐human primates.

The use of new world primates for biomedical research: an overview of the last four decades

Animal experimentation contributes significantly to the progression of science. Nonhuman primates play a particularly important role in biomedical research not only because of their anatomical, physiological, biochemical, and behavioral similarities with humans but also because of their close phylogenetic affinities. In order to investigate the use of New World primates (NWP) in biomedical research over the last four decades (1966–2005), we performed a quantitative study of the literature listed in bibliographic databases from the Health Sciences. The survey was performed for each genus of NWP that has been bred in the National Center of Primates in Brazil. The number of articles published was determined for each genus and sorted according to the country from which the studies originated and the general scientific field. The data obtained suggests that Brazil is a leader in generating knowledge with NWP models for translational medicine. Am. J. Primatol. 72:1055–1061, 2010.

Callithrix penicillata: A feasible experimental model for dengue virus infection

Although the murine models have the feasibility to reproduce some signs of dengue Virus (DENV) infection, the use of isogenic hosts with polarized immune response patterns does not reproduce the particularities of human disease. Our goal was to investigate the kinetics of peripheral blood biomarkers in immunocompetent Callithrix penicillata non-human primates subcutaneously infected with DENV-3. The viral load of infected animals was determinated by quantitative real time PCR. Measurements of DENV-3/IgM were performed, and several parameters were assessed by hemogram: red blood cells count, hemoglobin, hematocrit, white blood cells count, neutrophils, monocytes, lymphocytes, and platelets count. The coagulogram was performed by prothrombin time (PT), and activated partial thromboplastin time (APTT) assays. The renal function was monitored by urea and creatinine, and the liver function by the aspartate (AST), and alanine (ALT) aminotransferases. Also, the level of the cytokines IL-6, TNF-α, IL-2, IFN-γ, IL-4 and IL-5 was quantified during the experimental study. Data analysis was performed considering relevant differences when baseline fold changes were found outside from 0.75 to 1.5 range. Our data demonstrated that infected animals presented relevant signs of dengue disease, including peaks of viremia at 5 days-post-infection (dpi), peaks of anti-DENV-3 IgM at 15 dpi and hemaglutination inhibition assay (HIA) from 15 to at 60 dpi. Despite early monocytosis, slight neutrophilia and lymphocytosis, animals developed persistent leucopenia starting at 4 dpi. Anemia episodes were steady at 3-4 dpi. Patent thrombocytopenia was observed from 1 to 15 dpi with sporadic decrease of APTT. A substantial increase of ALT and AST was observed with higher peak at 4 dpi. Moreover, early increases of TNF-alpha and IFN-gamma besides late increase of IFN-gamma were observed. The analysis of biomarkers network pointed out two relevant strong axes during early stages of dengue fever, a protective axes TNF-alpha/Lymphocytes/Platelets, and a pathological IL-2/IL-6/Viremia/Monocyte/PT bond. Later on, the biomarker network highlighted the interaction IFN-gamma/PLT/DENV-3(IgM;HAI)/PT, and the involvement of type-2 cytokines (IL-4; IL-5). Our findings demonstrated that C. penicillata is a feasible experimental model for dengue virus infection, which could be useful to pathogenesis studies, discovery of novel antiviral drugs as well as to evaluate vaccine candidates against DENV.

Polymorphic color vision in captive Uta Hick's cuxiús, or bearded sakis (Chiropotes utahickae)

The pitheciines (Chiropotes, Pithecia, and Cacajao) are frugivorous Neotropical primates that specialize on the predation of seeds from unripe fruits, usually cryptic against the foliage. However, little is known about the color vision distribution within this taxon, and even less about the abilities shared by these animals regarding discrimination of chromatic targets. The aim of this study was to evaluate the color vision perception of captive Uta Hicks cuxiús, or bearded sakis (Chiropotes utahickae) through a behavioral paradigm of color visual discrimination, as well as to estimate, by genetic studies, the number and kinds of medium to long wavelength cone photopigment (opsins) encoded by this species. Among 12 cuxiús (7 males and 5 females) studied only 1 female was diagnosed as a trichromat. Results from genotyping were in line with our behavioral data and showed that cuxiús carried one (dichromat) or two (trichromat) medium to long wavelength pigments alleles, demonstrating a color vision polymorphism in C. utahickae similar to the majority of Neotropical Primates. Am. J. Primatol. 77:66–75, 2015.

Renal Evaluation of Aotus azarai infulatus by Ultrasonography and Serum Chemistry Profile

This study aimed to characterize anatomical and biochemical properties of owl monkey kidneys in order to provide normal reference values. Sixty‐nine Aotus azarai infulatus (45 males and 24 females) were divided into four different age groups (AG1: 3 months–1 year; AG2: 2–3 years; AG3: 4–6 years; and AG4: over 7 years old). The monkeys were evaluated with a serum chemistry profile, focusing on serum creatinine (SCr) and blood urea nitrogen (BUN) and with ultrasound. Mean body mass differed among the age groups. This significance was attributed to AG1 body mass being significantly lower than in AG2 and that in both AG2 and AG3 being significantly lower than in the two older age groups (AG3 and AG4). SCr and BUNconcentrations differed significantly between the sexes and SCr level correlated positively with age. In contrast, renal measurements did not differ between males and females. Left and right renal volumes did not differ significantly within age groups, or among AG2, AG3, and AG4. Renal volumes in AG1, however, while not differing from those in AG2, did differ significantly from those in AG3 and AG4. In conclusion, this study provides ultrasonographic reference values for the morphology the kidneys in A. a. infulatus. Evidence is also provided that SCr and BUNlevels in owl monkeys are influenced by the sex and age of the individual, factors that should be considered when interpreting test results. Am. J. Primatol. 74:482‐490, 2012.

EFFECT OF BIOMETRIC VARIABLES ON TWO-DIMENSIONAL ECHOCARDIOGRAPHIC MEASUREMENTS IN THE RED-TAILED BOA (BOA CONSTRICTOR CONSTRICTOR)

Abstract:  The effects of body biometrics on cardiac measurements and description of cardiac anatomy were performed in red-tailed boas (Boa constrictor constrictor) (n = 29) using real-time B-mode ultrasonography. Statistical comparison of measured cardiac metrics according to sex and body measurements demonstrated no significant difference between sexes but a highly significant linear increase between body length and mass and all cardiac metrics.

Conservação do sêmen e liquefação do coágulo seminal de macaco-prego (Cebus apella) em água de coco em pó (ACP-118®), em diferentes temperaturas

The aim of this study was to evaluate the powdered coconut water (PCW) in the semen conservation and seminal clot liquefaction. The semen of six adult male Cebus apella was collected by electroejaculation (EEJ), diluted in ACP-118® extender and stayed in water bath at 33, 35 and 37°C for 24 hours. The sperm integrity was evaluated by eosin-nigrosine staining every one hour during the six initial hours and after 24 hours of incubation. The average volumes and sperm concentrations of clotted and liquid fractions were 0.20±0.02 and 0.20±0.10mL, 1.1±0.3x108 and 1.3±0.9x107 sperm mL-1, respectively. Immediately after collection, only in a sample of liquid fraction was observed 20% motility and vigor 4, which stopped after 40 minutes. Most of the clot was liquefied in ACP-118® after 12 hours of incubation. The best observed treatment was 33°C, because it kept 47±12.8% of sperm integrity after 24 hours. It was concluded that the PCW extender is effective in the liquefaction of seminal clot and maintenance of sperm viability 24 hours after the EEJ at 33, 35 and 37°C.

Antibody-enhanced dengue disease generates a marked CNS inflammatory response in the black-tufted marmoset Callithrix penicillata.

Severe dengue disease is often associated with long‐term neurological impairments, but it is unclear what mechanisms are associated with neurological sequelae. Previously, we demonstrated antibody‐enhanced dengue disease (ADE) dengue in an immunocompetent mouse model with a dengue virus 2 (DENV2) antibody injection followed by DENV3 virus infection. Here we migrated this ADE model to Callithrix penicillata. To mimic human multiple infections of endemic zones where abundant vectors and multiple serotypes co‐exist, three animals received weekly subcutaneous injections of DENV3 (genotype III)‐infected supernatant of C6/36 cell cultures, followed 24 h later by anti‐DENV2 antibody for 12 weeks. There were six control animals, two of which received weekly anti‐DENV2 antibodies, and four further animals received no injections. After multiple infections, brain, liver, and spleen samples were collected and tissue was immunolabeled for DENV3 antigens, ionized calcium binding adapter molecule 1, Ki‐67, TNFα. There were marked morphological changes in the microglial population of ADE monkeys characterized by more highly ramified microglial processes, higher numbers of trees and larger surface areas. These changes were associated with intense TNFα‐positive immunolabeling. It is unclear why ADE should generate such microglial activation given that IgG does not cross the blood‐brain barrier, but this study reveals that in ADE dengue therapy targeting the CNS host response is likely to be important.

A novel method for capturing and monitoring a small neotropical primate, the squirrel monkey (Saimiri collinsi).

Squirrel monkeys (genus Saimiri) are agile, arboreal primates that are seldom captured in the wild due to their small body size (<1 kg) and large, non‐cohesive social groups (40–50 individuals). However, long‐term studies on these primates often require captures and permanent identification of individuals, in order to monitor their behavior and health. Here we report on a novel trapping method successfully used to capture Saimiri collinsi, in Eastern Amazonia, Brazil. Our objective was to capture as many individuals as possible from one social group of approximately 50 individuals, ranging over 150 ha of terra firme forest. Captures occurred in November and December 2013. We habituated animals to feed on a large platform located in a 123.5 m2 area enclosed by a green net (3 m high). Multiple individuals could freely enter and exit the area via four ropes affixed from surrounding trees to the platform. Once individuals were feeding inside the netted area on selected trapping days, the ropes were dropped remotely, eliminating their escape routes. We successfully trapped 21 different individuals of the social group (14 adults and 7 immatures) with this method. We conclude that this is a conceptually simple, effective method for trapping squirrel monkeys in most habitats, and possibly other small arboreal primates that live in large social groups. The present method was more effective than previous methods utilized to capture squirrel monkeys in the field, and has the advantages of: allowing for safe capture of several individuals simultaneously; enabling re‐captures; releasing of animals as a group at the site of capture; use of soft netting which facilitates safe capture of the monkeys. Am. J. Primatol. 77:239–245, 2015.

Avaliação ultrassonográfica e mensurações das glândulas adrenais em primatas não humanos neotropicais: mico-de-cheiro (Saimiri sciureus), macaco-da-noite (Aotus azarae infulatus) e bugio-ruivo (Alouatta guariba clamitans)

The adrenal glands have endocrine functions related to multiple vital functions and are closely related to the animals ability to adapt to stress. The ultrasound is the diagnostic method of choice for evaluation of glands in different species. Considering the scarce literature, one may question whether the adrenal disorders in nonhuman primates are uncommon or underdiagnosed, and a hypothesis exists that this fact is determined by the lack of parameters. The goal is to describe the sonographic features of the adrenal glands for three species of nonhuman primates kept in captivity: squirrel monkey (Saimiri sciureus), owl monkey (Aotus azarae infulatus) and howler monkey (Alouatta guariba clamitans). It is concluded that it is possible to identify the adrenal glands by ultrasound, and the reference standards have been established successfully for the species in question. It is noteworthy that the adaptation of animals in many stressful environments is often accompanied by a hypertrophy of the adrenal glands, so one should take into account that the measurements performed in this study were established in captive animals.