Manatees display diel trends in acoustic activity at two microhabitats in Belize

Many marine mammals exhibit diel trends in vocal production, which can provide information on habitat use and behavioral activity. In Belize, Antillean manatees (Trichechus manatus manatus) commonly inhabit small depressions in the substrate or deep-water coves known as "resting holes". Determining if manatees exhibit diel temporal trends in their call production rate and call types between microhabitats can provide insights into their diurnal and nocturnal activity patterns. Here, we investigate the diel vocalization patterns of wild Antillean manatees in two adjacent resting holes off of St. George's Caye, Belize. Recordings of manatees were made using a bottom-mounted hydrophone located near a reef barrier reef for nine days in July of 2017 and ten days in January of 2018. To explore if and how manatee acoustic activity differs between sites, we compared the number of calls per hour, the number of manatee positive hours, the number of tonal and atonal sounds, and the number of boats detected across sites. A total of 370 hours of acoustic recordings were analyzed resulting in the detection of 3,262 calls. There were no significant differences in the number of manatee calls produced per hour between sites. The average number of calls produced by manatees decreased over the course of several days. The proportion of tonal calls decreased with hours after sunset and increased in boat presence. These results suggest manatees in this region may exhibit different diel activity patterns which appear to be influenced by the characteristics of the environment. These findings can support ongoing conservation and management efforts to safeguard species in Belize.

Antillean manatee calves in captive rehabilitation change vocal behavior in anticipation of feeding

Captive animals typically develop anticipatory behaviors, actions of increased frequency done in anticipation of an event such as feeding. Anticipatory behaviors can be an indicator of an animal's welfare. However, for rehabilitating animals that are expected to be reintroduced into the wild, these behaviors need to be extinguished to ensure successful release. Scheduled activities such as feeding occur daily and vocalizations could potentially be used to identify anticipatory behavior. Here, we tested the hypothesis that manatee calves modify their vocal production rate as a form of anticipatory behavior. Vocalizations of two Antillean manatee (Trichechus manatus manatus) calves were recorded for 10 min before, during, and after feeding sessions at Wildtracks, a manatee rehabilitation center in Belize. The number of calls were counted across recording sessions and three acoustic parameters were measured from calls including duration, frequency modulation, and center frequency. A repeated measures ANOVA comparing the number of calls across sessions indicated manatees produced significantly more calls before feeding sessions than during and after sessions. In addition, manatees increased the duration and lowered the frequency of calls before feeding sessions. This information can give further insight on ways to improve rehabilitation protocols and manage human interactions to increase the overall survival rate of rehabilitated manatees when released back into the wild.

Genetic confirmation of Octopus insularis (Leite and Haimovici, 2008) in South Florida, United States using physical features and de novo genome assembly

The distribution of octopuses within the Octopus vulgaris species complex remains inadequately understood. Species determination can be complex and involves characterizing a specimen's physical features and comparing its genetic makeup to other populations. In this study, we present the first genetic confirmation of Octopus insularis (Leite and Haimovici, 2008) inhabiting the coastal waters of the Florida Keys, United States. We employed visual observations to identify species-specific body patterns of three wild-caught octopuses and used de novo genome assembly to confirm their species. All three specimens exhibited a red/white reticulated pattern on their ventral arm surface. Two specimens displayed body pattern components of deimatic display (white eye encircled by a light ring, with darkening around the eye). All visual observations were consistent with distinguishing features of O. insularis. We then compared mitochondrial subunits COI, COIII, and 16S in these specimens across all available annotated octopod sequences, including Sepia apama (Hotaling et al., 2021) as a control outgroup taxon. For species exhibiting intraspecific genomic variation, we included multiple sequences from geographically distinct populations. Laboratory specimens consistently clustered into a single taxonomic node with O. insularis. These findings confirm O. insularis presence in South Florida and suggest a more extensive northern distribution than previously assumed. Whole genome Illumina sequencing of multiple specimens enabled taxonomic identification with well-established DNA barcodes while also generating the first de novo full assembly of O. insularis. Furthermore, constructing and comparing phylogenetic trees for multiple conserved genes is essential for confirming the presence and delineation of cryptic species in the Caribbean.

Interchange of Southern Hemisphere humpback whales across the South Atlantic Ocean

The cosmopolitan distribution of humpback whales (Megaptera novaeangliae) is largely driven by migrations between winter low-latitude breeding grounds and summer high-latitude feeding grounds. Southern Hemisphere humpback whales faced intensive exploitation during the whaling eras and recently show evidence of population recovery. Gene flow and shared song indicate overlap between the western (A) and eastern (B1, B2) Breeding Stocks in the South Atlantic and Indian Oceans (C1). Here, we investigated photo-identification evidence of population interchange using images of individuals photographed during boat-based tourism and research in Brazil and South Africa from 1989 to 2022. Fluke images were uploaded to Happywhale, a global digital database for marine mammal identification. Six whales were recaptured between countries from 2002 to 2021 with resighting intervals ranging from 0.76 to 12.92 years. Four whales originally photographed off Abrolhos Bank, Brazil were photographed off the Western Cape, South Africa (feeding grounds for B2). Two whales originally photographed off the Western Cape were photographed off Brazil, one traveling to the Eastern Cape in the Southwestern Indian Ocean (a migration corridor for C1) before migrating westward to Brazil. These findings photographically confirm interchange of humpback whales across the South Atlantic and Indian Oceans and the importance of international collaboration to understand population boundaries.

Analysis of body condition indices reveals different ecotypes of the Antillean manatee

Assessing the body condition of wild animals is necessary to monitor the health of the population and is critical to defining a framework for conservation actions. Body condition indices (BCIs) are a non-invasive and relatively simple means to assess the health of individual animals, useful for addressing a wide variety of ecological, behavioral, and management questions. The Antillean manatee (Trichechus manatus manatus) is an endangered subspecies of the West Indian manatee, facing a wide variety of threats from mostly human-related origins. Our objective was to define specific BCIs for the subspecies that, coupled with additional health, genetic and demographic information, can be valuable to guide management decisions. Biometric measurements of 380 wild Antillean manatees captured in seven different locations within their range of distribution were obtained. From this information, we developed three BCIs (BCI₁ = UG/SL, BCI₂ = W/SL³, BCI₃ = W/(SL*UG²)). Linear models and two-way ANCOVA tests showed significant differences of the BCIs among sexes and locations. Although our three BCIs are suitable for Antillean manatees, BCI₁ is more practical as it does not require information about weight, which can be a metric logistically difficult to collect under particular circumstances. BCI₁ was significantly different among environments, revealing that the phenotypic plasticity of the subspecies have originated at least two ecotypes-coastal marine and riverine-of Antillean manatees.

Association of hepatosplenic schistosomiasis with HLA-DQB1*0201

Major histocompatibility class II alleles of 351 persons living in an area endemic for Schistosoma mansoni in northeastern Brazil were characterized at three loci (DRB1, DQA1, and DQB1). Contingency analyses were used to compare allele frequencies with high egg excretion, proliferative response to schistosome soluble egg antigens (SEA), and occurrence of severe, biopsy-confirmed hepatosplenic disease. There were no associations of HLA-DR or DQ with egg excretion. Patients positive for DRB1*01, DQA1*0101, or DQB1*0501 were less likely to respond to SEA than was the overall study population. However, using stringent Bonferroni correction (multiplying P values by the number of alleles tested; P x 35), none of these associations with SEA responsiveness remained significant. Hepatosplenic disease was less likely in patients positive for DRB1*11 and was more likely in patients positive for DRB1*07 or DQB1*0201. However, only the DQB1*0201 association remained significant (odds ratio = 3.72; P < .005) following Bonferroni correction.

Failure of schistosomiasis to significantly decrease testosterone levels in Brazilian men

Schistosomes can decrease the reproductive potential or castrate both invertebrate (snail) hosts as well as vertebrate (mouse, rat, and hamster) hosts. To determine if host castration occurs in human males, we examined testosterone levels in the sera of 38 Brazilian males, 16-35 years of age, who had Schistosoma mansoni infections. We found that individuals with intestinal schistosomiasis exhibited serum testosterone levels similar to those of noninfected controls. Four subjects with severe hepatosplenic disease also exhibited testosterone levels within the normal range. We did observe a negative correlation between parasite load (as predicted by fecal egg count) and testosterone levels but could not dissociate this relationship from the effect of age on either parameter. Therefore, in contrast to rodent models, host castration does not appear to be a usual side effect of human schistosomiasis.

Soluble intercellular adhesion molecules in human schistosomiasis: correlations with disease severity and decreased responsiveness to egg antigens

Granuloma formation, the principal pathologic consequence of infection with Schistosoma mansoni, is a complex process involving intricate cell-cell interactions in which intercellular adhesion molecules are likely to participate. To examine this possibility, sera of schistosomiasis patients in various clinical groups were assayed for the presence of soluble intercellular adhesion molecule 1 (sICAM-1) and soluble E-selectin (sE-selectin). Comparisons were made between groups with different infection intensities (as predicted by fecal egg count) as well as between groups with severe (hepatosplenic) or milder (intestinal) pathology. All groups had elevated levels of sICAM-1 compared with controls. Also, patients in the high egg-excreting and hepatosplenic groups had significantly higher levels of serum sICAM-1 than patients in the low-egg-excreting and intestinal groups, respectively. The levels of sE-selectin were significantly elevated in the sera of all patients except those in the hepatosplenic group compared with controls. Patients in the intestinal group had significantly higher levels of sE-selectin in their sera than did hepatosplenic group patients, but serum sE-selectin levels of high- and low-egg-excreting patients were comparable. A striking finding of this study was the inverse correlation observed between sICAM-1 levels and peripheral blood mononuclear cell responses to schistosome soluble egg antigens (SEA) but not with responses to other schistosome antigens, purified protein derivative, or mitogen. Because ICAM-1 can perform a costimulatory function in antigen-presenting cell-T cell interactions, it is possible that shedding of ICAM-1 in the granuloma microenvironment interrupts proper costimulation, leading to unresponsive SEA-specific T cells. In this way, sICAM-1 could be one factor contributing to the observed modulation of cellular responses to SEA in chronic human schistosomiasis.

[Toxoplasmosis of the central nervous system. Clinicopathological correlation with 7 autopsy cases]

O trabalho mostra o estudo anatomopatológico de 7 casos de Toxoplasmose do sistema nervoso central, com diagnósticos feitos exclusivamente em autópsias. O trabalho chama atenção para a dificuldade de diagnóstico clínico desta entidade e mostra dois casos de apresentação mais rara com manifestações clínicas e anatomopatológicas que simulam abscessos cerebrais. O comprometimento do plexo coróide, freqüente neste material, fortalece a idéia de que esta estrutura desempenha papel importante na disseminação da doença no sistema nervoso central.

Chronic glomerulonephritis associated with hepatosplenic Schistosomiasis mansoni

In a series of 36 cases of renal disease associated with hepatosplenic schistosomiasis the following morphologic types of glomerulonephritis were found: mesangio-capillary (33.2%), mesangial proliferative (25.0%), focal glomerular sclerosis (16.7%) and sclerosing glomerulonephritis (8.3%). No significant statistical differences were found when these results were compared with those from 36 cases of glomerulonephritis not associated with hepatosplenic disease. On the other hand, endocapillary glomerulonephritis was found to be predominant in the latter group of cases. These results did not substantiate the assumption that mesangio-capillary glomerulonephritis is specifically related to hepatosplenic schistosomiais. However, if the types of glomerulonephritis that predominantly involve the me-sangium are considered together, they are significantly associated with hepatosplenic schistosomiasis. Mesangial involvement is known to occur in other parasitic diseases and that may be related to a common immunopathogenesis.

Glucagon kinetics in fasting: physiological elevations in serum 3,5,3'-triiodothyronine increase the metabolic clearance rate of glucagon

We have attempted to determine if the elevated plasma glucagon concentration and delayed MCR of glucagon (MCRg) observed during caloric restriction are related to the decreased serum T3 that also occurs during fasting. Twelve obese subjects received a 3-h iv glucagon infusion during a 4-day fed period (1000 kCal/day) and again on approximately the third fasting day. Five patients fasted without receiving exogenous T3 (control group), whereas seven subjects fasted but also received 5 micrograms T3 orally every 4 h (T3 group) to maintain approximately the same serum T3 levels in the fed and fasting periods. Glucagon production rates (GPR) were derived by multiplying the MCRg by the respective basal plasma glucogon concentrations. In the control group, the MCRg was 442 +/- 55 ml/m2 . min in the postabsorptive state and decreased to 312 +/- 49 ml/m2 . min (P < 0.025) during fasting, whereas in the T3-treated group, the postabsorptive MCRg was 304 +/- 22 ml/m2 . min and increased during fasting to 417 +/- 47 ml/m2 . min (P < 0.025). The GPRs in the control group were statistically unaltered between the fed (27.7 +/- 3.0 ng/m2 . min) and fasted (22.9 +/- 1.8 ng/m2 . min) intervals, but GPR increased from 37.9 +/- 6.1 ng/m2 . min during fasting to 49.2 +/- 9.1 ng/m2 . min when T3 was administered (5 micrograms every 4 h). The net plasma glucose increment in response to glucagon decreased from 18 mg/dl (fed) to 5 mg/dl (fast) in the control patients and from 10 mg/dl (fed) to 7 mg/dl (fast) in the T3-treated subjects. In the T3-treated patients, serum T3 averaged 124 ng/dl during both feeding and fasting, and rT3 was 55 +/- 6 ng/dl during feeding and 49 +/- 5 ng/dl during fasting. In summary, the results from this study indicate that during fasting 1) slight physiological alterations in serum T3 influence the MCRg, and 2) T3 increases the GPR and blocks the customary fasting-induced rise in rT3. Conceivably, decreased T3 is an early event in the fasting state which serves to decrease the MCRg, a process which subsequently regulates glucose homeostasis.

[Anatomo-pathological study of the brain in idiopathic cardiomegaly]

The pathological findings in the brain of patients who died with idiopathic cardiomegaly are reported. The major findings in the 38 studied cases were cerebral infarcts (10,5%) and cerebral atrophy (7,9%) besides the nonspecific histological changes represented by neuronal ischemic alteration, satellitosis of nerve cells and swollen and hyperplasia of endothelial cells in capilaries of the cerebral cortex. These findings were considered a consequence of the venous stasis of the congestive heart failure. These data were compared to those seen in the brain of patients with heart failure in the course of chronic Chagas disease. The morphological findings were similar. The frequence of infarcts and atrophy was higher in the cases of Chagas disease and the cerebral atrophy was seen in an younger group of patients compared to the cases of idiopathic cardiomegaly. It seems that there is another factor also responsible for the occurrence of cerebral atrophy in Chagas disease, since from the clinical and hemodynamic point of view both cardiopathies have many similarities.

A new form of abdominal zygomycosis different from mucormycosis: report of two cases and review of the literature

Two cases of abdominal zygomycosis occurring in apparently healthy individuals are presented. They had chronic evolution and histologic aspects similar to those found in subcutaneous zygomycosis. In both cases there was involvement of stomach and transverse colon. In one case the liver, biliary system, pancreas, and duodenum were also involved. Fungal cultures were negative. These cases apparently represent a new form of zygomycosis because, although visceral in localization, the disease presents an evolution and histologic features different from the classical form of visceral zygomycosis. Since this infection can be treated the importance of early diagnosis is stressed.