Suicide While Locked Up in Texas: Risk Factors for Death by Suicide in Custody

In the United States, suicide is a leading cause of death in prisons and jails, with incarcerated individuals being nine times more likely to die by suicide than the general population. Identifying vulnerabilities at each stage of custody (prebooking, jail, prison) and factors that increase suicide risk can improve prevention efforts. A hierarchical binary logistic regression was conducted on data from the Texas Justice Initiative's Deaths in Custody Report. Variables included race/ethnicity, sex, age at death, days in custody, classification of crime as violent or nonviolent, and custody type of prebooking, jail, or prison. Among main effects, when compared to suicide rates in prison, jail suicide deaths were over three and a half times more likely (OR = 3.61), and the period of prebooking emerged as a period of staggering risk of suicide death, with suicides being over 5,000% more likely than at other stages of custody (OR = 50.86). When interactions were entered, Latinx individuals were at a particularly increased risk of suicide death (OR = 10.46), likelihood of suicide death decreased with each year of age (OR = .89), nonviolent offenders were just under three and a half times more likely to die by suicide when compared to violent offenders (OR = 3.45), and each stage of custody was shown to affect the relationship between age-related rates of suicide in different ways. Results call for further investigation into suicide among understudied populations in corrections, such as Latinx individuals, juveniles in the prison system, and nonviolent offenders, to identify the groups at the highest risk of premature death in correctional systems.

The impact of different neurobehavioral symptoms on suicidal ideation and perceived likelihood of future suicidality

Existing literature suggests that psychological and functional impairment, independent of head injury severity, can increase suicide risk. This study explores the impacts of self-perceived dysfunction within four neurobehavioral symptom clusters-vestibular (e.g., dizziness, balance), somatosensory (e.g., headaches, nausea, vision), affective (e.g., anxious, irritable mood), and cognitive (e.g., concentration, memory, indecision)-on current suicidal ideation and the perceived likelihood of future suicidal ideation and attempts. Community participants (n = 309; Mage = 36.88; 51.6% female; 79.6% White) completed the Neurobehavioral Symptom Inventory (NSI) and the Self-Injurious Thoughts and Behaviors-Short Form (SITBI-SF). Quantile regression analysis was used to explore the effects of the four neurobehavioral symptom clusters at different levels of suicidal ideation intensity, perceived likelihood of future suicidal ideation, and self-perceived likelihood of future suicide attempt. Controlling for past head injuries and suicide attempts, affective symptoms were significantly associated with a moderate and high average intensity of current suicidal ideation. Somatosensory symptoms were significantly associated with a moderate perceived likelihood of future suicidal ideation. Finally, vestibular symptoms were significantly associated with a moderate perceived likelihood of a future suicide attempt. These findings highlight the critical need to consider a broader spectrum of symptoms, including chronic physical symptoms, when assessing suicide risk. Furthermore, they underscore the need to expand beyond affective symptoms as an explanation for increased suicidality and examine additional mechanisms through which chronic physical symptoms can increase suicide risk.

Do Crisis Details Differentiate Suicide-Related 911 Call Outcomes?

Background The outcomes of calling 911 for suicide crises remain largely unexplored. Aims To investigate how characteristics of individuals in a suicidal crisis (e.g., age, gender identity, help-seeking source, means, disclosure of historical suicidality, or self-harm) may differentiate outcomes when contacting 911. Method The authors analyzed 1,073 Washington State Police 911 call logs, coding for characteristics and outcome (unknown, monitoring, intervention, adverse outcome). Descriptive and inferential statistics, including multinomial logistic regressions, were used to explore associations. Results When individuals experiencing a suicidal crisis were referred by bystander or associates' observations, there was a greater likelihood of adverse outcome. Self-referral led to a greater likelihood of intervention. Referral from the suicidal individual contacting a known associate led to a greater likelihood of monitoring. Any disclosure of means led to a greater likelihood of intervention or adverse outcomes. Positive disclosure of historical suicidality or self-harm was more likely to result in monitoring. Limitations The dataset was intended for operational use in acute suicidality triage rather than research purposes. Conclusion This study highlights the importance of supporting first responders with research to enhance their triage of people experiencing suicidal crises.

Major adverse cardiac events in critically ill COVID-19 patients

Background

Critically ill patients hospitalized with COVID-19 are at high risk of developing major adverse cardiac events (MACE).

Purpose

This study aimed to identify independent predictors of MACE after intensive care unit (ICU) admission which could be used to identify high-risk patients who may benefit from preventive strategies.

Methods

We retrospectively analyzed patients consecutively admitted to an ICU with COVID-19 and followed them for a median period of 7 months. Patients admitted due to trauma or emergent surgery were excluded. Logistic regression analysis was performed to evaluate which clinical characteristics predicted MACE. MACE was defined as all-cause ICU mortality, new-onset heart failure, acute coronary syndrome, ventricular arrythmias, pulmonary embolism, myocarditis, and stroke (ischemic or hemorrhagic).

Results

A total of 297 patients was included in the analysis. Median age was 62 (IQR 17) years, and most patients were male (198 patients, 66.7%). From a total of 297 patients, 108 (36.4%) developed at least one MACE: ICU all-cause mortality (92 patients, 31.0%), new-onset heart failure (27 patients, 9.1%), acute coronary syndrome (7 patients, 2.4%), ventricular arrythmias (7 patients, 2.4%), pulmonary embolism (13 patients, 4.4%), myocarditis (4 patients, 1.3%), and stroke (5 patients, 1.7%).

Univariate logistic regression analysis showed that the clinical variables associated with MACE were male sex, older age, APACHE II score, SAPS II score, hypertension, hyperlipidemia, known coronary artery disease, heart failure, new-onset atrial fibrillation, need for invasive mechanical ventilation, duration of mechanical ventilation, and vasopressor use. In multivariate logistic regression analysis, we found that the MACE's independent predictors were older age, higher APACHE II score, and new-onset atrial fibrillation. Main results are presented in Table 1.

Conclusion(s)

Among critically ill COVID-19 patients, older age, higher APACHE II score, and new-onset atrial fibrillation independently predicted MACE.

Funding Acknowledgement

Type of funding sources: None.

Atrial fibrillation in COVID-19 patients admitted to an intensive care unit: prevalence and prognosis

Background

The association between atrial fibrillation (AF) and prognosis has been studied in non-COVID-19 patients, but few studies reflect the reality of critically ill COVID-19 patients admitted to a general intensive care unit (ICU).

Purpose

This study sought to investigate the relationship between previous and new-onset AF in COVID-19 patients admitted to an ICU and prognosis.

Methods

We retrospectively analyzed patients consecutively admitted to an ICU with COVID-19 and followed them for a median period of 7 months. Patients admitted due to trauma or emergent surgery were excluded from the analysis. Three groups were identified: without AF (G1), with prior history of AF (G2), and with new-onset AF (G3). Groups were compared, with special interest regarding ICU mortality, duration of mechanical ventilation, length of hospitalization, major adverse cardiac events (MACE), and re-hospitalization. MACE was defined as all-cause ICU mortality, new-onset heart failure, acute coronary syndrome, ventricular arrhythmias, pulmonary embolism, myocarditis, and stroke (ischemic or hemorrhagic).

Results

A total of 297 patients was included in the analysis: without AF (248 patients, 83.5%), with prior history of AF (15 patients, 5.1%), and with new-onset AF (34 patients, 11.4%). Median age was 62 (IQR 17) years, and most patients were male (198 patients, 66.7%).

Patients with a prior history of AF were older [median (IQR), G1 60 (16), G2 71 (12), G3 67 (15) years, p=0.001], were more likely to have a history of coronary artery disease (G1 4.9%, G2 26.7%, G3 11.8%, p=0.002), and history of heart failure (G1 6.5%, G2 33.3%, G3 17.6%, p<0.001). Patients with new-onset AF had a longer duration of mechanical ventilation [median (IQR), G1 9 (13), G2 11 (16), G3 18 (12) days, p<0.001), longer ICU length of stay [median (IQR), G1 12 (10), G2 13 (12), G3 19 (15), p=0.001], higher ICU mortality rate (G1 27.0%, G2 33.3%, G3 58.8%, p=0.001), and higher rate of MACE (G1 31.9%, G2 33.3%, G3 70.6%, p<0.001), compared to the other groups. There were no differences regarding sex distribution, other baseline comorbidities, need for invasive mechanical ventilation, vasopressor use, and re-hospitalization rates among groups. Most AF patients were treated with beta-blockers (39.6%) and amiodarone (77.1%), but only 68.8% of patients received anticoagulation (G2 92.9%, G3 58.8%), which may reflect that physicians underestimate the prognosis of new-onset AF.

In multivariate analysis, new-onset AF (OR 3.07, 95% CI 1.42–6.67, p=0.005) and older age (OR 1.07, 95% CI 1.04–1.09, p<0.001) remained independent predictors of ICU mortality. Main results are presented in Table 1. Kaplan-Meier survival curves are presented in Figure 1.

Conclusion(s)

This study shows that critically ill COVID-19 patients with AF present a worse prognosis compared to patients without AF, and new-onset AF is an independent predictor of ICU mortality and MACE.

Funding Acknowledgement

Type of funding sources: None.

Prognostic value of cardiac troponin in critically ill COVID-19 patients

Funding Acknowledgements

Type of funding sources: None.

Background/Introduction

Among patients with COVID-19, there is a high prevalence of cardiovascular disease and myocardial injury from the infection, especially in critically ill patients.

Purpose

This study sought to investigate the relationship between elevated admission high-sensitive troponin I in COVID-19 patients admitted to an intensive care unit (ICU) and prognosis.

Methods

We retrospectively analyzed patients consecutively admitted to an ICU with COVID-19, with a median follow-up of 10 months. Patients who were diagnosed with acute coronary syndrome, either died or were discharged within 48 hours of admission, and who did not have a cardiac troponin measurement in the first 48 hours, were excluded.

Two groups were identified, with normal troponin and with elevated troponin. Groups were compared, with special interest regarding in-hospital mortality, duration of mechanical ventilation, in-hospital diagnosis of heart failure, and length of hospitalization. Global mortality (in-hospital and during follow up) and re-hospitalization were compared. To compare survival, a Kaplan-Meier curve with log rank test was performed.

Results

From a total of 219 patients, after applying the exclusion criteria, 100 patients were included in the analysis, mean age was 62.9 ±12.5 years, and 74% were male.

Troponin was normal in 77% of patients and elevated in 23%. Median troponin was 11 (IQR=26) ng/L (reference range <34 ng/L).

Patients with elevated troponin were older (66.5 ±12.0 vs 61.6 ±12.5 years, p=0.036). Gender, comorbidities, vasopressor use, and APACHE II score were similar among groups. Patients with elevated troponin presented a higher ICU mortality (16.9% vs 47.8%, p=0.002) and higher global mortality (22.1% vs 47.8%, p=0.016). Re-hospitalization rates, ICU length of stay and duration of mechanical ventilation were similar among groups.

In multivariate analysis, after adjustment for age and APACHE II score, an elevated troponin remained an independent predictor of ICU mortality (OR=3.40, 95% CI 1.08-10.4, p=0.036), but not an independent predictor of global mortality (OR=2.75, 95% CI 0.86-8.80, p=0.087).

Kaplan-Meier analysis (Figures 1 and 2) showed that patients with elevated troponin had higher ICU (p=0.008) and global mortality (p=0.008) when compared to patients with normal admission troponin.

Conclusion(s)

The present study shows that elevated high-sensitive cardiac troponin I at admission predicts ICU and global mortality in critically ill COVID-19 patients. Cardiac troponin is as easy-to-use tool that may help to identify patients who benefit from tighter monitoring both during hospitalization and after discharge.

Cardiovascular disease in critically ill COVID-19 patients

Funding Acknowledgements

Type of funding sources: None.

Background/Introduction

It is now well known that patients with COVID-19 have a high prevalence of cardiovascular disease. COVID-19 is also associated with a substantial degree of cardiovascular involvement. However, the impact of cardiovascular disease (CVD) and cardiovascular risk factors on the natural history of COVID-19 is much less characterized.

Purpose

To characterize the prognostic impact of CVD and cardiovascular risk factors in COVID-19 patients admitted to an Intensive Care Unit (ICU).

Methods

We retrospectively analyzed patients consecutively admitted to an ICU with COVID-19, with a median follow-up of 10 months. Patients who either died or were discharged in the first 48 hours of admission were excluded.

Three groups were identified: (1) established CVD – presence of either heart failure, coronary artery disease and/or peripheral artery disease; (2) at higher risk of CVD – arterial hypertension, dyslipidemia, diabetes mellitus and/or smoking, in the absence of established CVD; and (3) at lower risk of CVD – i.e. none of the above.

Groups were compared, with special interest regarding in-hospital mortality, duration of mechanical ventilation, length of hospitalization. Global mortality (in-hospital and during follow up), and re-hospitalization were also compared. To compare survival, a Kaplan-Meier and multivariate Cox regression analysis were performed.

Results

Overall, 219 patients were identified, mean age was 62.1 ±11.9 years, 67.1% were male, 71 (32.4%) died in the ICU, 78 (35.6%) died during follow-up, and 14 (6.4%) were re-hospitalized.

30 patients (13.7%) had established CVD, 144 (65.8%) were at higher risk of CVD, and 45 (20.5%) were at lower risk of CVD. Patients with established CVD were older than patients at higher risk of CVD, and both were older than patients at lower risk (68.0 ±8.4 vs 62.0 ±11.3 vs 56.0 ±13.0 years, p <0.001). ICU mortality was 56.7%, 30.6%, and 22.2% for patients with established CVD, at higher risk of CVD, and at lower risk of CVD, respectively (p = 0.005). Re-hospitalization rate, ICU length of stay, and duration of mechanical ventilation were similar among groups.

Patients with established CVD were at significantly higher risk of ICU mortality (HR 2.42, 95% CI 1.08-5.46, p = 0.033), and higher risk of global mortality (HR 2.16, 95% CI 1.03-4.52, p = 0.042), compared to patients at higher and lower risk of CVD; in patients at higher and lower risk of CVD, ICU and global mortality was similar. In multivariate Cox regression, after adjusting for age and risk scores, established CVD was not an independent predictor of mortality. Kaplan-Meier survival curves are presented in figures 1 and 2.

Conclusion(s)

Almost 80% of patients admitted to an ICU with COVID-19 had established or were at higher risk of CVD. Patients with established CVD have a higher risk of death, although its presence is not an independent predictor of death.

Effects of ivermectin treatment during prepubertal and pubertal period on sexual parameters and sexual behavior in adulthood in rats

Pediculosis is a parasitic disease that is considered a serious global public health problem. It is caused by the ectoparasite that is popularly known as lice, mainly affecting children in early childhood. The most commonly used treatment to combat this parasitosis is the macrocyclic lactone ivermectin (IVM). However, the use of IVM is contraindicated in children who are younger than 5 years old or who weigh <15 kg because some types of drugs that are used during certain periods of brain maturation can lead to behavioral disorders. The present study evaluated the effects of IVM treatment during the prepubertal and pubertal period on sexual behavior in adulthood in male rats. Genital grooming, preputial separation, sexual behavior, sexual motivation, relative organ weight, the gonadosomatic index, and histopathology were evaluated. Oral dose of 0.2 mg/kg (therapeutic dose) of a commercial IVM formulation was administered. IVM affected genital grooming but did not influence preputial separation in prepubertal rats. Prepubertal IVM administration did not impair sexual behavior in adult rats, with the exception of the time of residence with female rats in the sexual motivation test. It did not affect relative organ weights, with the exception of the relative weight of the full seminal vesicle. It did not alter the gonadosomatic index, and no histopathological alterations were observed in different organs. These results indicate that administration of a therapeutic dose of IVM during the prepubertal and pubertal period does not alter parameters of sexual development or sexual behavior in adult male rats.

Ivermectin does not interfere with seminal and hormonal parameters in male rabbits

Ivermectin (IVM) is a macrocyclic lactone used as a broad spectrum antiparasitic agent against nematodes and arthropods. It is mainly used in the control of parasitic infections of domestic animals, and recently has been used in humans to treat onchocerciasis, scabies, and pediculosis. In mammals, evidence has indicated that macrocyclic lactones interact with gamma-aminobutyric acid (GABA)-mediated chloride channels. The GABAergic system is known to be involved in the manifestation of sexual behavior, and previous studies have shown that IVM impaired sexual behavior in both male and female rats. Thus, considering that IVM may interfere with the sexual sphere, this study evaluated the temporal (1 up 60 days) effects of exposure to IVM (0.2 and 1.0 mg/kg, administered subcutaneously) on seminal and hormonal parameters of male rabbits. In male rabbits, the spermatozoa concentration, motility and morphology, the integrity of the plasmatic, acrosomal and mitochondrial membranes of the spermatozoa, the organ weights, gonadosomatic index, serum testosterone concentrations, histopathological findings were evaluated and hematological and serum biochemical analysis was conducted. No changes were observed in male seminal parameters evaluated by spermatozoa concentration, motility, and morphology, nor the potential for fertilization evaluated by the integrity of the plasmatic, acrosomal, and mitochondrial membranes of the spermatozoa; there was also no interference in serum testosterone concentration, serum biochemistry and hematological parameters. The findings of this study using the artificial vagina for collection of semen and computer-assisted semen analysis showed that IVM at doses of 0.2 and 1.0 mg/kg of SC did not alter any of the semen parameters of rabbits evaluated for up to 60 days after administration.

Sensory attributes and volatile composition of a dry white wine under different packing configurations

The aim of this work was to study the effect of different configurations of packaging on the volatile composition and sensory properties of a white wine. Certain oenological parameters were also evaluated. Bag-in-box (BIB) and glass bottles sealed with two different cork stoppers, natural and Neutrocork (technical), were used in the experiments. Analysis were carried out before packaging and after 3, 6 and 12 months of storage. Results showed that wines packaged in BIB presented higher levels of brown color than wines in bottles sealed with corks. In all packaging configurations, the content of free SO₂ decreased with storage time; however, BIB wines showed a lower content of free SO₂ than bottle wines during 12 months. Moreover, wines under BIB presented a significant lower amount of 2-phenylethanol, 2-phenylethyl acetate, isoamyl acetate, ethyl butanoate, ethyl hexanoate, ethyl octanoate, linalool and β-damascenone than bottled wines.

Colon cancer metastasis to the thyroid gland: A case report

INTRODUCTION

Thyroid metastases from colorectal cancer are uncommon and few cases are described in literature.

CASE PRESENTATION

A 64-year-old female patient presented with an asymptomatic right cervical nodule with a rapid growth six years after sigmoidectomy for cancer and two years after resection of colorectal lung metastases. Increased CA 19.9 was identified and a thoracoabdominal CT scan revealed the onset of new metastatic bilateral pulmonary lesions. Neck ultrasonography showed a suspicious nodule in the right thyroid lobe, and Fine-needle Aspiration Cytology (FNAC) of the nodule lead to the diagnosis of colorectal cancer metastasis. A right thyroid lobectomy with right central lymph node dissection was performed. The patient underwent chemotherapy with response, but this was posteriorly suspended due to haematological side effects, and the disease spread.

DISCUSSION

Thyroid metastases from colorectal cancer are rare, but, with the improvement of radiologic exams and the higher survival rate of these patients, more cases are being described. The majority of the cases present pulmonary and hepatic metastases and the prognosis is poor. The decision to operate and the type of operation depend on the extent of the metastatic disease and the patient's overall condition.

CONCLUSION

A low threshold of suspicion is crucial to make a timely diagnosis of thyroid metastases from colorectal cancer. Treatment is controversial, but, without surgery, the need may arise for tracheostomy.

Piometra em uma leoa (Panthera leo): relato de caso

A piometra é uma infecção aguda ou crônica do útero que ocorre frequentemente em cadelas não castradas, podendo também ocorrer em gatas domésticas e selvagens, sendo poucos os estudos relacionados à piometra em grandes felídeos. O objetivo deste relato foi descrever um caso de piometra em uma leoa (Panthera leo) de cativeiro, as lesões de necropsia e histológicas, bem como os resultados da análise microbiológica. Uma leoa com aproximadamente 23 anos, pertencente a um criadouro conservacionista de Santa Maria-RS, foi encontrada morta pela manhã em seu recinto. Após coleta de dados, procedeu-se à necropsia e à coleta de material para análise histopatológica e bacteriológica. A análise microbiológica revelou predomínio das bactérias Streptococcus sp. e Escherichia coli no conteúdo purulento do útero, caracterizando como piometra, e a bactéria predominante em plasma, fígado e medula óssea foi E. coli. De acordo com o laudo histopatológico, as alterações observadas nessa leoa sugerem um quadro de septicemia grave, sendo a origem do foco infeccioso bacteriano, provavelmente, a piometra. Considera-se importante chamar a atenção dos médicos veterinários de animais selvagens para um diagnóstico precoce dessa doença, que é comum em cadelas, mas que pode acometer também felídeos selvagens e levá-los à morte.

Proximate analysis, backwards stepwise regression between gross calorific value, ultimate and chemical analysis of wood

The gross calorific value (GCV), proximate, ultimate and chemical analysis of debark wood in Portugal were studied, for future utilization in wood pellets industry and the results compared with CEN/TS 14961. The relationship between GCV, ultimate and chemical analysis were determined by multiple regression stepwise backward. The treatment between hardwoods-softwoods did not result in significant statistical differences for proximate, ultimate and chemical analysis. Significant statistical differences were found in carbon for National (hardwoods-softwoods) and (National-tropical) hardwoods in volatile matter, fixed carbon, carbon and oxygen and also for chemical analysis in National (hardwoods-softwoods) for F and (National-tropical) hardwoods for Br. GCV was highly positively related to C (0.79 * * *) and negatively to O (-0.71 * * *). The final independent variables of the model were (C, O, S, Zn, Ni, Br) with R(2)=0.86; F=27.68 * * *. The hydrogen did not contribute statistically to the energy content.

Vince – a case study

Abstract. Vince was an unusual hurricane that developed over the North Atlantic Ocean in an unexpected area, on October 2005. In this work, the authors analyze its background and genesis over the ocean, making use of satellite imagery and numerical models. The impacts on sea state are investigated both numerically and observationally. Landfall over the Iberian Peninsula is monitored with surface observations and a radar system at Algarve (Portugal).

Seasonal analysis of semen characteristics, serum testosterone and fecal androgens in the ocelot (Leopardus pardalis), margay (L. wiedii) and tigrina (L. tigrinus)

Captive adult male ocelots (Leopardus pardalis, n = 3), margays (L. wiedii, n = 3) and tigrinas (L. tigrinus, n = 4) in two locations in southern Brazil were studied for 14 consecutive months to evaluate the effect of season on testicular function. Reproductive evaluations, including testicular measurements, electroejaculation and blood collection were conducted monthly. Fecal samples were collected weekly for androgen metabolite analysis to assess testicular steroidogenic activity. Ocelots had the highest number of motile spermatozoa in the ejaculate (114.7+/-15.8 x 10(6); P < 0.05), the highest percentage of morphologically normal spermatozoa (82.4+/-1.2%; P < 0.05) and the highest concentration of fecal androgens (1.71 vs. 0.14 microg/g; P < 0.05). Margays and tigrinas had lower numbers of motile spermatozoa (23.4+/-2.8 x 10(6), 74.2+/-8.9 x 10(6), respectively), lower percentages of morphologically normal spermatozoa (57.4+/-2.8, 59.2+/-3.5%, respectively), and lower fecal androgen concentrations (0.15+/-0.01, 0.23+/-0.01 microg/g, respectively). Serum testosterone concentrations were similar among the three species. Fecal androgen concentrations were not affected by season, with the exception of the ocelot where concentrations were higher (P < 0.05) in the summer. Ejaculates were collected throughout the year; however, peaks in average sperm production were observed during the summer for all species. In summary, this study has identified several species differences in male testicular traits among ocelots, margays and tigrinas. Results of longitudinal reproductive assessments suggest males of each species are capable of breeding throughout the year.

Reproductive steroid hormones and ovarian activity in felids of the Leopardus genus

Reproductive endocrine patterns were characterized in female ocelots (Leopardus pardalis; n = 3), tigrinas (Leopardus tigrinus; n = 2), and margays (Leopardus wiedii; n = 2) housed in captivity in southern Brazil. Females were maintained as singletons and exposed to natural fluctuations in photoperiod. Cyclic changes in ovarian steroids were monitored by analyzing estrogen and progestogen metabolites in fecal samples collected five times weekly for 14 to 18 months. Based on intervals between fecal estrogen peaks, mean (+/- SEM) duration of the estrous cycle was 18.4 +/- 1.6 days for the ocelots (range, 7-31 days; n = 75 cycles), 16.7 +/- 1.3 days for the tigrinas (range, 11-27 days; n = 23 cycles), and 17.6 +/- 1.5 days for the margays (range, 11-25 days; n = 32 cycles). Fecal progestogen analyses combined with two laparoscopic observations of the ovaries confirmed that ocelots and tigrinas did not ovulate spontaneously. In contrast, non-mating-induced luteal phases of 40.1 +/- 6.3 days in duration (range, 30-60 days) were observed frequently in both margays. There was no evidence of gonadal seasonality in margays in either follicular or luteal activity. In ocelots, cyclic changes in estrogen excretion were observed during each month of the year; however, only one female cycled continuously. In the other two ocelots, periods of acyclicity of several months' duration were observed. It was not possible to conclude whether tigrinas were aseasonal because estrous cyclicity was observed in only one of two individuals. In the female that cycled, a 3-month period of acyclicity was observed in the late fall/early winter. These data demonstrate similarities among three felid species of the genus Leopardus, including evidence they are polyestrous but experience unexplained periods of ovarian inactivity. Only the margays differed by exhibiting occasional spontaneous, non-mating-induced ovulations. Historically, these species have not bred well in captivity. However, it is hoped that understanding the biological similarities and differences among them could lead to improved management strategies that may one day result in increased reproductive success. Zoo Biol 20:103-116, 2001. Copyright 2001 Wiley-Liss, Inc.