COMPARISON OF TRANSCUTANEOUS ULTRASOUND AND COMPUTED TOMOGRAPHY EVALUATION OF KIDNEY SIZE AND EVALUATION OF ADRENAL GLAND SIZE USING ULTRASOUND IN A COLONY OF CALLIMICOS ( CALLIMICO GOELDII).

Both kidney and adrenal gland disease have been identified in callimicos ( Callimico goeldii). Ultrasonography (US) and computed tomography (CT) are routinely utilized in veterinary patients with suspected renal or adrenal disease to determine size, shape, and echogenicity of these organs. No previous US and CT kidney and adrenal gland measurements have been published for callimicos. In this study, 14 callimicos were anesthetized using isoflurane via facemask to evaluate kidney and adrenal gland size using US for both organs and CT for kidneys. Animals were considered clinically healthy based on history, physical examination, hematology, serum chemistry, urinalysis, and abdominal US. Ultrasound organ measurements for length (L), width (W), and height (H) in centimeters (mean/median, 95% confidence interval) in clinically healthy animals were right kidney (L = 1.90, 1.76-2.01; W = 1.05, 0.97-1.13; H = 1.59, 1.48-1.69), left kidney (L = 1.84, 1.72-1.95; W = 1.16, 1.04-1.28; H = 1.54, 1.43-1.65), right adrenal gland (L = 0.38, 0.33-0.57; H = 0.19, 0.15-0.31) and left adrenal gland (L = 0.36, 0.32-0.39; H = 0.18, 0.17-0.20). All kidney measurements were positively correlated with animal weight ( P < 0.05) but had no significant correlation to age. Measurements did not have any significant relationship to evaluated blood and urine parameters. Results from this study establish baseline measurements for callimico kidneys and adrenal glands to help clinicians use these imaging modalities for evaluation of these organs in this endangered species.

Determination of vertebral heart score in Goeldi's monkeys (Callimico goeldii).

BACKGROUND: Goeldi's monkeys (Callimico goeldii) are callitrichid primates commonly kept in zoological collections, and to date, no cardiac parameters have been recorded. The vertebral heart score (VHS) is an objective method of evaluation of cardiac size well documented in domestic mammals, and the aim of this study was to determine the VHS in Goeldi's monkeys. METHODS: In this retrospective study, right lateral radiographs of thirteen clinically well animals were reviewed and vertebral heart score determined. RESULTS: The vertebral heart score was found to be 9.35 ± 0.31. CONCLUSIONS: The observed value appears consistent within the study population and with values for other primate species. The value determined may be of benefit in objectively evaluating cardiac size in this species.

Lost and found: The third molars of Callimico goeldii and the evolution of the callitrichine postcanine dentition.

This study tests the hypothesis that the third molars of Callimico goeldii represent a reversal in evolutionary tooth loss within the Callitrichinae. Loss of third molars is part of a suite of unusual characters that has been used to unite marmosets and tamarins in a clade to the exclusion of Callimico. However, molecular phylogenetic studies provide consistent support for the hypothesis that marmosets are more closely related to Callimico than to tamarins, raising the possibility that some or all of the features shared by marmosets and tamarins are homoplastic. Here, I use the binary-state speciation and extinction (BiSSE) model and a sample of 249 extant primate species to demonstrate that, given the shape of the primate phylogenetic tree and the distribution of character states in extant taxa, models in which M3 loss is constrained to be irreversible are much less likely than models in which reversals are allowed to occur. This result provides support for the idea that the last common ancestor of Callimico and marmosets was characterized by the two-molared phenotype. The M3s of Callimico therefore appear to be secondarily derived rather than plesiomorphic. This conclusion may also apply to the other apparently plesiomorphic traits found in Callimico. Hypotheses regarding the re-evolution of M3 in the callitrichine clade and the origin and maintenance of the two-molared phenotype are discussed.

Identification of sperm head subpopulations with defined pleiomorphic characteristics in ejaculates of captive Goeldi's monkeys (Callimico goeldii).

The aim of this study was to evaluate the incidence of pleiomorphisms and its influence on the distribution of sperm morphometric subpopulations in ejaculates from the vulnerable Goeldi's monkey (Callimico goeldii) by using a combination of computerized analysis system and Principal Component Analysis (PCA) methods. Each sperm head was measured for four primary spermatozoal head dimensional parameters (area [A (µm(2))], perimeter [P (µm)], length [L (µm)] and width [W (µm)]) and three head shape derived parameters (ellipticity [(L/W)], elongation [(L-W)/(L+W)] and rugosity [(4πA/P(2))]). Six separate subpopulations (SPs) were identified: SP1, constituted by very large, narrow and very elliptical spermatozoa (A=16.85±1.56µm(2), W=2.75±0.42µm and ellipticity=2.16±0.24); SP2, characterized by average sized, short, wide and round spermatozoa (A=15.00±1.92µm(2), L=5.06±0.49µm, W=3.51±0.31µm and ellipticity=1.44±0.15); SP3, represented by small, wide and slightly round spermatozoa (A=14.95±1.75µm(2), W=3.47±0.29µm and ellipticity=1.48±0.14); SP4 included very small, short and very round spermatozoa (A=14.15±2.38µm(2), L=4.90±0.57µm and elongation=0.18±0.05); SP5 consisted of average sized and slightly elliptical spermatozoa (A=15.14±1.72µm(2) and ellipticity=1.49±0.14); and SP6 included large and round spermatozoa (A=16.30±1.62µm(2) and elongation=0.19±0.04). There were differences in the sperm subpopulation distribution (P<0.001) among the five donors analyzed. In conclusion, the results of the current study confirmed that the use of computer sperm analysis methods combined with PCA cluster analyses are useful methods to identify, classify, and characterize different sperm head morphometric subpopulations in neotropical primates. Broadening our knowledge of C. goeldii sperm morphometric abnormalities as well as developing reliable techniques for sperm evaluation may be essential for ex situ conservation of this threatened species.

Radiographic evaluation of neonatal skeletal development in Callimico goeldii reveals closer similarity to Callithrix jacchus than to Saguinus oedipus.

The phylogenetic affinities of the neotropical Goeldi's monkey (Callimico goeldii) have long been a matter of debate. Whereas most morphological evidence appears to place Callimico in a sister group position relative to the Callitrichidae, genetic studies place C. goeldii within the Callitrichidae and suggest that it is more closely related to marmosets than to tamarins. The present study presents the first radiographic analysis comparing the secondary limb bone ossification of newborn C. goeldii with representatives of the marmosets (Callithrix jacchus) and tamarins (Saguinus oedipus). The state of secondary ossification of the epiphysis and short bones is classified into three different ontogenetic stages. Our results reveal that in terms of the number of ossification centers, C. goeldii is significantly closer to C. jacchus than to S. oedipus. This is the first morphological study to support the findings of molecular studies, and the results suggest that C. goeldii is more closely related to marmosets than to tamarins.

Patterns of positional behavior in mixed-species troops of Callimico goeldii, Saguinus labiatus, and Saguinus fuscicollis in northwestern Brazil.

We present the results of a 4-month field investigation of positional behavior, vertical ranging, and species differences in limb proportions and body mass in a mixed-species troop of Saguinus fuscicollis, Saguinus labiatus, and Callimico goeldii in northwestern Brazil. Despite certain similarities in overall positional repertoire, patterns of positional behavior varied significantly between species. Travel in Callimico occurred principally in the lowest levels of the canopy, and was characterized by an exaggerated form of hindlimb-dominated bounding (bounding-hop), and leaping to and from vertical trunks (55.1% of leaps). In contrast, saddle-back tamarins traveled in the lower and middle levels of the canopy, and engaged in a range of leaping behaviors, including stationary leaps (37.3%), acrobatic leaps (31.3%), and trunk-to-trunk leaps (20%). Red-bellied tamarins exploited the highest levels of the arboreal canopy. Travel in this species was dominated by quadrupedal bounding and acrobatic leaps (67% of leaps) that began and ended on thin, flexible supports. Species differences in positional behavior correlated with species differences in limb proportions and locomotor anatomy, and provide a framework for understanding niche partitioning in mixed-species troops of Saguinus and Callimico.

A reexamination of the phylogenetic position of Callimico (primates) incorporating new mitochondrial DNA sequence data.

The New World monkeys are divided into two main groups, Callitrichidae and Cebidae. Callimico goeldii shares traits with both the Cebidae and the Callitrichidae. Recent morphological phyletic studies generally place Callimico as the most basal member of the Callitrichidae. In contrast, genetic studies (immunological, restriction fragment, and sequence data) have consistently placed Callimico somewhere within the Callitrichidae, not basal to this clade. A DNA sequence data set from the terminal 236 codons of the mitochondrial ND4 gene and the tRNA(His), tRNA(Ser), and tRNA(Leu) genes was generated to clarify the position of Callimico. The sequences of 887 base pairs were analyzed by maximum-parsimony, neighbor-joining, and maximum-likelihood methods. The results of these various methods are generally congruent and place Callimico within the Callitrichidae between the marmosets (Callithrix and Cebuella) and the tamarins (Saguinus and Leontopithecus). Combined analyses of all suitable nuclear and mitochondrial gene sequences confirm the position of Callimico between the marmosets and the tamarins. As available molecular evidence indicates that Callimico is more closely related to the marmosets than to the tamarins, a reconsideration of the morphological evidence in light of the consensus tree from DNA sequence analyses is warranted. The marmosets and tamarins share four morphological characters (loss of the third molar, loss of the hypocone, reduced body size, reproductive twinning). Dwarfism may have evolved repeatedly among the Callitrichidae. It is well-known that the loss of a character can occur many times independently. The reproduction of marmosets and tamarins is extremely specialized and it is difficult to imagine that this complex and unique twinning system evolved separately in marmosets and tamarins. However, it is possible that a secondary reversal to single offspring took place in Callimico.