Morphometry, topography and arterial supply of the thyroid gland in rhesus monkeys (Macaca mulatta Zimmermann, 1780).

The purpose of this research was to investigate the measures, topography, and vascularization of the thyroid gland in Macaca mulatta, a non-human primate. The study involved the dissection of ten male adult cadavers of Macaca mulatta. The length, width, and thickness of the right lobe of the thyroid were 2.552 ± 0.341, 1.019 ± 0.137, and 0.729 ± 0.137 cm. These measures in the left thyroid lobe were 2.406 ± 0.299, 1.013. ± 0.087, and 0.769 ± 0.083 cm. The study found no significant differences in the measures of the left and right lobes of the thyroid gland in rhesus monkeys. Regarding topography, the thyroid gland was located ventrolateral to the trachea, similar to its position in other mammal species. The cranial pole of the gland was closely related to the cricoid or thyroid cartilage, while the caudal pole showed variable positioning to the tracheal rings. The isthmus, a thin band of tissue connecting the lobes, was present in all specimens. The cranial thyroid artery was found to originate from the external carotid artery in most specimens. It supplied the thyroid gland and sent branches to muscles in the neck region. The caudal thyroid artery, originating from the common carotid artery, provides additional blood supply to the gland and sends a branch to the esophagus. This research contributes to knowledge about the thyroid gland in non-human primates, specifically Macaca mulatta. The findings provide critical information for comparative studies and understanding the thyroid gland's role in health and disease.

Detection of Toxoplasma gondii in two southern Wooly spider monkeys (Brachyteles arachnoides-Geoffroy, 1806) from the Rio de Janeiro primate center, Brazil.

BACKGROUND: Toxoplasmosis led to the death of two Brachyteles arachnoides, an endangered atelid. METHODS: The diagnosis was established by necropsy, histopathological, immunohistochemical and ultrastructural changes. RESULTS: The analysis confirms the presence of Toxoplasma gondii. CONCLUSIONS: This report contributes to the development of protocols for health surveillance on maintenance and conservation of southern muriquis.

Respiratory syncytial virus (RSV) pneumonia in a southern muriqui (Brachyteles arachnoides).

BACKGROUND: An adult male Brachyteles arachanoides, kept in captivity since 1990, was found dead without apparent clinical evidence. METHODS: Necropsy report, histopathology, immunohistochemistry, and ultrastructural examination were conducted. RESULTS: Pulmonary syncytial cells were positive for respiratory syncytial virus (RSV), and ultrastructural examination revealed viral particles inside macrophages compatible with the Paramyxoviridae family. CONCLUSIONS: Muriquis are susceptible to RSV pneumonia followed by respiratory distress syndrome and death.

Helmintos oxiuridae parasitos de Iguana iguana (Squamata, Lacertilia, Iguanidae) procedentes do Brasil / Oxiuridae helminths parasites of Iguana iguana (Squamata, Lacertilia, Iguanidae) in Brazil

The results of a study on nematode fauna occurring in wild iguanas (Iguana iguana) from Brazilian Northeast (Alagoas and Maranhão) and Central-west (Goiás and Mato Grosso) areas were presented. Six adult iguanas, three males and three females, were necropsied and the digestive system removed to examination. All the iguana specimens were heavily parasitized. The helminths diagnosed were: Ozolaimus cirratus in the cecum and colon of five iguanas; Ozolaimus megatyphlon in cecum, colon and rectum of three iguanas; and Alaeuris vogelsangi in the small intestine, cecum, colon and rectum of five animals. Two larvae of Ozolaimus sp. were recovered from the pyloric region of the stomach of one iguana. The three diagnosed species of nematodes were reported for the first time in the Brazilian Central-West region.

Morfologia macroscópica do aparelho reprodutor feminino de Leontopithecus cativos (Lesson, 1840) Primates-Callitrichidae / Gross morphology of the female genital tract of captive Leontopithecus (Lesson, 1840) Primates-Callitrichidae

Descreveu-se o sistema reprodutor feminino em três espécies de mico-leão Leontopithecus (Lesson 1840), cativos: L. rosalia, L. chrysopygus e L. chrysomelas. A vulva está delimitada pelos lábios vulvares menores e com clitóris conspícuo. A superfície do períneo urogenital apresenta elevações papilares mais concentradas nos lábios vulvares, conferindo-lhe aspecto rugoso. O vestíbulo vaginal constitui um tubo muscular de parede espessa que se estende da rima da vulva até o óstio da vagina. A vagina é um tubo muscular alongado e achatado dorsoventralmente, que comunica o vestíbulo vaginal ao colo uterino. O útero piriforme está localizado na porção caudal da cavidade abdominal. Craniolateralmente abrem-se tubas uterinas convolutas e ovários grosseiramente fusiformes de superfície lisa.

It is described the female genital tract of three species of lion tamarin: Leontopithecus rosalia, L. chrysopygus, and L. chrysomelas. Fifteen animals were selected from the Museum of the Center of Primatology of Rio de Janeiro - CPRJ/FEEMA. The vulva is delimited by the labia and has a conspicuous clitoris. The surface of the urogenital perineum has papillary elevations more concentrated in the labia, which results in a rough aspect. The vestibule is a thick-walled muscular tube, extending from the pudendal cleft to the vaginal orifice. The vagina is an elongated and flat muscular tube, which communicates dorsoventrally the vestibulum and the cervix of uterus. The pyriform uterus is located in the caudal portion of the abdominal cavity. Craniolaterally, the convolute uterine tubes open, enveloping the ovaries, which are roughly fusiform with a smooth surface.

Phylogenetic studies of the genus Cebus (Cebidae-Primates) using chromosome painting and G-banding.

BACKGROUND: Chromosomal painting, using whole chromosome probes from humans and Saguinus oedipus, was used to establish karyotypic divergence among species of the genus Cebus, including C. olivaceus, C. albifrons, C. apella robustus and C. apella paraguayanus. Cytogenetic studies suggested that the species of this genus have conservative karyotypes, with diploid numbers ranging from 2n = 52 to 2n = 54. RESULTS: Banding studies revealed morphological divergence among some chromosomes, owing to variations in the size of heterochromatic blocks. This analysis demonstrated that Cebus species have five conserved human associations (i.e., 5/7, 2/16, 10/16, 14/15, 8/18 and 3/21) when compared with the putative ancestral Platyrrhini karyotype. CONCLUSION: The autapomorphies 8/15/8 in C. albifrons and 12/15 in C. olivaceus explain the changes in chromosome number from 54 to 52. The association 5/16/7, which has not previously been reported in Platyrrhini, was also found in C. olivaceus. These data corroborate previous FISH results, suggesting that the genus Cebus has a very similar karyotype to the putative ancestral Platyrrhini.

Ocorrência de Acanthocephala em Leontopithecus (Lesson, 1840), cativos: aspectos clínico-patológicos. Callitrichidae-Primates / Acanthocephala infections in captives lion tamarins Leontopithecus (Lesson, 1840): clinical pathologic aspects. Callitrichidae-Primates

Estudaram-se achados de necropsia de 454 espécimens de Leontopithecus. Quatorze (3,1 por cento) apresentaram-se infectados por acantocéfalos intestinais identificados como Prosthenorchis elegans (Diesing, 1861). Não foram observadas diferenças na ocorrência do parasito quanto à espécie, origem - cativos ou selvagens - e sexo. Clinicamente os animais apresentaram-se com o pelame eriçado, apatia, inapetência, dores abdominais e diarréia. Em dois animais parasitados (14,2 por cento), observou-se perfuração da parede intestinal. As lesões encontradas caracterizaram-se por uma grave enterite ulcerativa. A ocorrência desses parasitos reforça a necessidade do estabelecimento de protocolos sanitários rígidos no manejo das espécies de primatas do neotrópico

This study assessed the autopsy findings of 454 Leontopithecus specimens, 14 of which (3.1 percent) were infected by intestinal Acanthocephala identified as Prosthenorchis elegans (Diesing, 1861). No difference in the occurrence of the parasite was observed regarding the species, origin (captive or wild) and sex of the lion tamarins. Clinically, the animals had spiked coat, apathy, inappetence, abdominal pain and diarrhea. Two of the parasitized animals (14.2 percent) had perforation of the intestinal wall. The lesions found were characterized as a severe ulcerative enteritis. The occurrence of such parasites highlights the need for establishing strict sanitary protocols for the management of the neotropical primate species

Leptospiral antibodies in captive lion tamarins (Leontopithecus sp) in Brazil.

Serum samples from 73 lion tamarins of three species living at the Centro de Primatologia do Rio de Janeiro were tested for antibodies against serovars of Leptospira interrogans by microscopic agglutination test. Antibodies were detected in serum samples of 15% of tested samples. Seroreactivity prevalence was lower than that described in other non-human primates and could be explained by the arboreal behaviour of these animals. Icterohaemorrhagiae was the most common serogroup.

Stereology of the liver in three species of Leontopithecus (Lesson, 1840) Callitrichidae--primates.

Studies on liver morphology and stereology are relevant to the comparative anatomical and pathological research. They also facilitate the use of non-human primates in basic research, which has substantially supported studies in human medicine. Quantitative studies of liver structures have also been more extensive in Old World primates and other vertebrates. Twenty-three livers of adult lion tamarins were studied (six Leontopithecus rosalia, seven Leontopithecus chrysomelas, and 10 Leontopithecus chrysopygus), dissected, and fixed in 10% neutral buffered formalin solution. For stereological quantification, the liver was regarded as consisting of parenchyma (hepatocytes) and stroma (non-hepatocytes). The volume density (V(v)) was determined by point counting, and the disector method was used to obtain the numerical density of hepatocytes (N(v)). Hepatic stereological differences among the three species of lion tamarins were not statistically significant. Therefore, the pooled V(v[hepatocyte]) and V(v[stroma]) could be determined as 96.2 and 7.4%, respectively, and N(v[hepatocyte]) as 500.33 x 10(6) cm(-3). Significantly different, the values found for V(v[hepatocyte]) and N(v[hepatocyte]) in lion tamarins were, respectively, 0.09 and 2.8 times greater than those in baboons, and 0.17 and 3.8 times greater than those in man. However, the V(v[stroma]) was 1.04 times smaller than that in baboons and 1.79 times smaller than that in man.

Stereology of the myocardium in Leontopithecus (Lesson, 1840) callitrichidae - primates.

Rare morphological features of the Leontopithecus cardiovascular system have been reported in the literature. The samples analyzed in this study came from 33 specimens of Leontopithecus from the collection of the Center of Primatology of Rio de Janeiro-FEEMA (CPRJ-FEEMA). Morphometry and stereological data were obtained from all animals. Adult body weights of L. rosalia were the lowest, the greatest being those of L. chrysopygus caissara; body weights of L. chrysomelas and L. c. chrysopygus were similar and in between those of the two former species. Cardiomyocytes (left ventricular myocardium) were bigger in adults than in infants. The myocardium of L. rosalia showed focal fibrosis, fatty vacuoles, and hyalinization. In L. chrysomelas the myocardium showed areas of fibrosis and presence of mononuclear cells. Fibrosis and areas of congestion were observed in L. c. chrysopygus; areas of disorganization and vascular congestion were found in L. c. caissara. In L. rosalia infants, a greater density of vessels per myocardial area and a greater length density of vessels were observed as compared with those of L. chrysomelas. In adults, L. chrysomelas showed greater density of connective tissue in the myocardium than L. c. chrysopygus and L. c. caissara did. In L. rosalia, cardiomyocyte nuclei had a greater area density than those of the other forms of Leontopithecus. These characteristics may explain the faster development of L. rosalia infants as compared with that of L. chrysomelas and L. c. chrysopygus kept under the same handling conditions at the CPRJ-FEEMA.

Multiple nuclear insertions of mitochondrial cytochrome b sequences in callitrichine primates.

We report the presence of four nuclear paralogs of a 380-bp segment of cytochrome b in callitrichine primates (marmosets and tamarins). The mitochondrial cytochrome b sequence and each nuclear paralog were obtained from several species, allowing multiple comparisons of rates and patterns of substitution both between mitochondrial and nuclear sequences and among nuclear sequences. The mitochondrial DNA had high overall rates of molecular evolution and a strong bias toward substitutions at third codon positions. Rates of molecular evolution among the nuclear sequences were low and constant, and there were small differences in substitution patterns among the nuclear clades which were probably attributable to the small number of sites involved. A novel method of phylogenetic reconstruction based on the large difference in rates of evolution at different codon positions among mitochondrial and nuclear clades was used to determine whether different nuclear paralogs represent independent transposition events or duplications following a single insertion. This method is generally applicable in cases where differences in pattern of molecular evolution are known, and it showed that at least three of the four nuclear clades represent independent transposition events. The insertion events giving rise to two of the nuclear clades predate the divergence of the callitrichines, whereas those leading to the other two nuclear clades may have occurred in the common ancestor of marmosets.

Characterization of constitutive heterochromatin of Callithrix geoffroyi (Callitrichidae, Primates) by restriction enzymes and fluorochrome bands.

The neotropical primate genus Callithrix comprises two groups of species, jacchus and argentata, which inhabit distinct geographical regions and manifest different fur coloration and constitutive heterochromatin (CH) markers in their karyotypes. In this investigation the CH of a representative of the jacchus group, Callithrix geoffroyi, was analysed using fluorochromes and restriction enzymes in situ. To clarify the source of the constitutive heterochromatin of both groups, the data obtained in the jacchus group were compared with those published in the argentata group obtained by the same techniques. The C-bands of C. geoffroyi (four specimens, 2n = 46) were centromeric in all chromosomes, and distally located in pairs 6 and 22. The Alu I, Hae III, Hin fI, Rsa I, Dde I, Mbo I, and Msp I restriction endonucleases and CMA3 and DAPI fluorochromes produced different bands, which allowed the characterization of four distinct types of constitutive heterochromatin in the C. geoffroyi genome. Several of these types of heterochromatin were present in the ancestor of the two groups of species, jacchus and argentata, while others originated after their cladogenesis.

Morphological and morphometric age-related changes of the upper thoracic aorta in Leontopithecus (Lesson, 1840) (callitrichidae--primates).

Few morphologic aspects of Leontopithecus are listed in the literature, which does not provide sufficient knowledge of those simians. However, such results are important to evaluate the potential of those species as a model for studying comparative pathology. In this study, the material came from the collection of the Museu de Primatologia do Centro de Primatologia do Rio de Janeiro, fixed in 10% formalin pH 7.2. The samples were 33 individuals (five infant and five adult L. rosalia, L. chrysomelas, L. chrysopygus chrysopygus, and three adult L. chrysopygus caissara). The sections of the thoracic aorta were prepared for histological study and measurements were obtained. In the infant Leontopithecus, the aorta presents endothelial line and subendothelial space, the tunica media is not comparatively very thick. In the adults, the aorta showed enlarged tunica intima with consequent thick arterial wall, which increased with the aging process. The atheromatous plates were seen in the aortic wall of all adult L. chrysopygus chrysopygus, in two adult L. rosalia and only one adult L. chrysomelas. Differences in the aortic internal and external diameters were not significant in infants. In the adults, no significant difference was found among L. rosalia, L. chrysomelas and L. c. caissara, although the average of the aortic internal diameter in L. chrysomelas was larger than in L. c. caissara. In infant and adults L. c. chrysopygus, the thickness of the thoracic aorta is larger than in the other forms of Leontopithecus. These findings suggest a morphometric and morphologic aortic difference among the species of Leontopithecus, which could have biological significance that needs major investigation in the future.

Cranial and mandibular morphometry in Leontopithecus Lesson, 1840 (Callitrichidae, primates).

In this paper, we report on a craniometric analysis comparing the species of lion tamarins, Leontopithecus Lesson, 1840. Seventeen cranial and mandibular measures were taken on skulls of 59 adult crania: 20 L. rosalia (14 females and 6 males); 13 L. chrysomelas (6 females and 7 males); 23 L. chrysopygus (8 females and 15 males), and 3 L. caissara (1 female and 2 males). All specimens were from the Rio de Janeiro Primate Center (CPRJ-FEEMA, Brazil), except the specimens of L. caissara. Statistical treatment involved a one-way analysis of variance (the Bonferroni test) and discriminant analysis, comparing cranium and mandibles separately to determine variables which best distinguished groups and to group the specimens, using size corrected methods. The Mahalanobis distance was computed from the centroids of each group. Seven measures distinguished females of L. chrysopygus with L. rosalia, six to L. rosalia with L. chrysomelas, and L. chrysopygus with L. chrysomelas. In males, the numbers of measures statistically different were 5, 4, and 3 of the pairwise comparisons above mentioned. Cranial base length and orbital breadth were the only measures that were significantly different in all three dyads, considering both sexes. For the cranium, function 1 of the Discriminant Analysis accounted for 52.4% of the variance and function 2 accounted for 40.3%. Both functions exhibited a significant value for Wilks' lambda (P<0.0001) and 96.6% of specimens were correctly classified. For the mandible, the first two functions provided a significant discrimination 51.1% and 44.9%, respectively, and 69.5% of the correct classification. Orbital breadth and cranial base length contributed most in the cranial analysis, while mandibular length and mandibular body height to mandibular ones. The analyses performed in this study (univariate and multivariate) demonstrated that cranial and mandibular morphology is significantly different among species of Leontopithecus. Despite of sample size, L. caissara shows morphological distances to L. chrysopygus in cranial analysis. However, other investigations are necessary to confirm this.

Molecular phylogeny of new world primates (Platyrrhini) based on beta2-microglobulin DNA sequences.

Neotropical primates, traditionally grouped in the infraorder Platyrrhini, comprise 16 extant genera. Cladistic analyses based on morphological characteristics and molecular data resulted in topologic arrangements depicting disparate phylogenetic relationships, indicating that the evolution of gross morphological characteristics and molecular traits is not necessarily congruent. Here we present a phylogenetic arrangement for all neotropical primate genera obtained from DNA sequence analyses of the beta2-microglobulin gene. Parsimony, distance, and maximum likelihood analyses favored two families, Atelidae and Cebidae, each containing 8 genera. Atelids were resolved into atelines and pitheciines. The well-supported ateline clade branched into alouattine (Alouatta) and ateline (Ateles, Lagothrix, Brachyteles) clades. In turn, within the Ateline clade, Lagothrix and Brachyteles were well-supported sister groups. The pitheciines branched into well-supported callicebine (Callicebus) and pitheciine (Pithecia, Cacajao, Chiropotes) clades. In turn, within the pitheciine clade, Cacajao and Chiropotes were well-supported sister groups. The cebids branched into callitrichine (Saguinus, Leontopithecus, Callimico, Callithrix-Cebuella), cebine (Cebus, Saimiri), and aotine (Aotus) clades. While the callitrichine clade and the groupings of species and genera within this clade were all well supported, the cebine clade received only modest support, and the position of Aotus could not be clearly established. Cladistic analyses favored the proposition of 15 rather than 16 extant genera by including Cebuella pygmaea in the genus Callithrix as the sister group of the Callithrix argentata species group. These analyses also favored the sister grouping of Callimico with Callithrix and then of Leontopithecus with the Callithrix-Callimico clade.

Electrophoretic polymorphisms and their taxonomic implications in Callitrichini (Primates, Platyrrhini).

Five hundred forty-three blood samples from 15 populations of the four genera of callitrichin primates were studied electrophoretically. Polymorphism and genetic distances were estimated for 20 loci, 13 of which were polymorphic. The lion tamarin (Leontopithecus) studied here exhibited the least variability for these loci, while the monospecific Cebuella showed the most. The genetic distances observed between Callithrix and Cebuella genera support previous evidence indicating a close taxonomic relationship between them. Genetic distance values obtained in this study also support the synonimyzation of the kuhli form with Callithrix jacchus penicillata.

Steroid excretion during the ovarian cycle in captive and wild muriquis, Brachyteles arachnoides.

Urine, feces, and copulation frequency were collected from two captive muriqui females, Brachyteles arachnoides, at the Centro de Primatologia do Rio de Janeiro following the resumption of postpartum ovarian cycles. Fecal steroid profiles from seven wild muriqui females at the Estação Biologica de Caratinga, Minas Gerais, Brazil, were compared to the captive females to determine the approximate patterns of steroid excretion relative to the urinary LH peak. Hormonal profiles from one of the captive female muriquis revealed a discrete urinary LH peak. For this female, fecal progesterone increased on the same day as the urinary LH peak, while fecal estradiol increased 6 days later and urinary steroids increased 5 days later. For both captive females, the onset of fecal progesterone increase was preceded by the onset of copulations, which occurred during at least a 5-day period. The complete fecal hormonal profiles of the one captive female for which continuos data were available were similar to those found in wild muriqui monkeys, with the onset of an increase in sustained progesterone levels occurring several days prior to the onset of sustained estradiol increase. These patterns suggest that fecal progesterone may be excreted rapidly in this species. The onset of sustained increase in fecal progesterone levels, together with the consistent delay in the onset of the sustained increase in estradiol, may provide the best indicators of the periovulatory period for muriqui females.

Stereology of the myocardium in two species of Callithrix (Callitrichidae, primates).

The majority of studies on cardiac morphology have concentrated on Old World monkeys. Ten marmoset hearts of the genus Callithrix were studied (5 hearts of C. jacchus and 5 of C. penicillata), dissected and fixed in a 10% buffered formaldehyde solution, pH 7.2. Unbiased stereological estimates were obtained from isotropic uniform random sections of the myocardium. For stereological quantification the myocardium was regarded as consisting of cardiac myocytes and interstitium. The volume density (Vv) was determined by point counting. We used the disector method to obtain the numerical density of the cardiac myocytes (Nv[nuclei]). Myocardial stereological differences between the two species of marmoset were not statistically significant. We can therefore determine the pooled Vv[myocyte] and Nv[nuclei] as 68.6% and 41.6% (10(3)/mm3) respectively. The values found for Vv[myocyte] and Nv[nuclei] in the marmoset are respectively about 23.0 and 92.0% greater than those of the baboon, and respectively 57.3 and 45.5% greater than those in man. In contrast, the mean myocyte volume in the marmoset is not significantly different to that of man but is almost 36.0% less than that of the baboon.