To develop effective conservation and management actions, it is important to examine anthropogenic disturbance patterns and their impact on wildlife. We examined variation in the behavioral and ...physiological stress response of the Critically Endangered Mexican mantled howler monkeys Alouatta palliata mexicana in relation to two types of anthropogenic disturbance, habitat spatial patterns and presence of humans or their livestock (noise and presence nearby primates). We studied four groups (42 individuals) in two forest fragments at the Los Tuxtlas Biosphere Reserve for a total of 1100 observation hours, during which we recorded the howler monkeys’ vocalizations, locomotion and vigilance. We additionally collected fecal samples to determine the concentrations of glucocorticoid metabolites (fGCM). Howler monkeys vocalized less and moved more when in more spatially disturbed locations and when exposed more time to nearby noise but spent less time in locomotion when humans were present. fGCM were only related to human presence, suggesting that habitat spatial patterns are less of a challenge than human presence. This may be related to the generally unpredictable nature of the latter. Although our study does not allow determining whether the behavioral and physiological responses of howler monkeys to disturbance are costly, from a conservation standpoint it may be more prudent to assume that they are and design strategies to mitigate them. In this sense, actions aimed at reducing anthropogenic noise could benefit the conservation of Mexican mantled howler monkeys.
We examined variation in the behavior and physiological stress of the Critically Endangered Mexican mantled howler monkeys in relation to spatial (changes in habitat spatial patterns) and ongoing disturbance (anthropogenic noise and human presence). Individuals vocalized less and moved more when they were in more disturbed locations and were exposed to longer noises. Physiological stress was only related to ongoing disturbance, suggesting that spatial disturbance is less of a challenge than ongoing disturbance. Our study does not allow determining whether the responses of howler monkeys to disturbance are costly, but from a conservation standpoint it may be more prudent to assume that they are, and design strategies to mitigate them, than to wait until more evidence for such costs is available, which could happen too late. Thus, actions aimed at reducing anthropogenic noise could benefit the conservation of this species.
Non-lethal impacts of dogs on primates have seldom been assessed. We used an experimental approach to determine if mantled howler monkeys (Alouatta palliata) perceive dog barks as an aversive ...stimulus and thus display physiological and behavioral responses toward simulated barks. For one year (1754 h of observations) we studied 16 adult males belonging to five groups in Los Tuxtlas (Mexico), and recorded the occurrence of naturally occurring dog barks, their sound pressure level (SPL), and the behavioral responses of howler monkeys to barks. We then exposed males to bark playbacks at two SPL treatments, 40 and 80 dB in a total of 50 experiments. We assayed glucocorticoid metabolite concentrations in fecal samples (fGCM) as a marker of the physiological stress response of males. We also recorded the duration of vigilance, vocalizations, and flight in relation to playbacks. Naturally occurring barks were frequent and usually elicited behavioral responses by males. fGCM concentrations increased after bark playbacks and with stimuli intensity. Time spent vigilant increased following playbacks independently of stimuli intensity but both vocalizations and flight were linked to stimuli intensity: vocalizations were the longest after barks played-back at 80 dB, but males spent more time fleeing in response to 40 dB bark playbacks. These results provide evidence that dog barks are pervasive in the habitat of mantled howler monkeys living at Los Tuxtlas and disturb males, both physiologically and behaviorally. Although the potential costs of physiological and behavioral responses could not be determined, there is sufficient evidence to assume that they do have negative impacts on individuals. Therefore, our study provides avenues for future research on dog-wildlife interactions and valuable information for the design of conservation actions aimed at mitigating the impact of dogs on mantled howler monkeys.
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•The effects of dog disturbance on primates have seldom been assessed.•We used playback experiments to examine the impact of barks on mantled howler monkey physiology and behavior.•Physiological stress increased with dog bark intensity and behavioral responses were variable.•Dog barks disturb mantled howler monkeys, both physiologically and behaviorally.
Anxiety disorders are the most prevalent mental health disorders and are associated with substantial disability and reduced well-being. It is unknown whether the relative impact of different anxiety ...disorders is due to the anxiety disorder itself or to the co-occurrence with other anxiety disorders. This study compared the functional impact of combinations of anxiety disorders in primary care out-patients.
A total of 1004 patients with panic disorder (PD), generalized anxiety disorder (GAD), social anxiety disorder (SAD) or post-traumatic stress disorder (PTSD) provided data on their mental and physical functioning, and disability. Multivariate regressions compared functional levels for patients with different numbers and combinations of disorders.
Of the patients, 42% had one anxiety disorder only, 38% two, 16% three and 3% all four. There were few relative differences in functioning among patients with only one anxiety disorder, although those with SAD were most restricted in their work, social and home activities and those with GAD were the least impaired. Functioning levels tended to deteriorate as co-morbidity increased.
Of the four anxiety disorders examined, GAD appears to be the least disabling, although they all have more in common than in distinction when it comes to functional impairment. A focus on unique effects of specific anxiety disorders is inadequate, as it fails to address the more pervasive impairment associated with multiple anxiety disorders, which is the modal presentation in primary care.
When sons and daughters impart different fitness benefits, mothers should bias investment according to offspring sex, in some cases modifying offspring sex ratios. Sex allocation in monotocous ...organisms is expected to be costlier than for polytocous species, as it imposes a greater loss of reproductive effort in terms of mating and fertilization. Here, we show that variation in glucocorticoid concentrations around the time of conception predicts infant sex in a monotocous anthropoid, the black howler monkey (Alouatta pigra), suggesting that sex allocation is linked to a hormonal mechanism that affects early embryonic development. Glucocorticoids signal environmental conditions, and in our study, their variation was positively related to factors affecting infant survival. These results offer insight into sex allocation strategies in monotocous organisms.
Our study showed that black howler monkey mothers give birth to daughters only when their fecal glucocorticoid metabolites are below a threshold of ca. 200 ng g−1. Furthermore, mothers living in disturbed forest fragments have higher glucocorticoid levels, and more often give birth to sons. These results offer insight into sex allocation strategies in monotocous organisms.
Objective
Reproduction entails several challenges to primate females, among which energetic costs are remarkable at certain stages of the reproductive cycle. Still, females may use behavioral and ...physiological strategies to cope with those challenges. We had previously reported covariation between female energetic condition through the reproductive cycle and time‐budget adjustments in mantled howler monkeys (Alouatta palliata). Accordingly, we suggested that behavioral flexibility allowed coping with the energetic challenges of reproduction. Subsequent evidence from the same population, however, suggested otherwise, so we performed a follow‐up study on the variation in female reproductive energetics based on a larger sample of females.
Methods
We studied 48 free‐ranging adult females at Los Tuxtlas (Mexico). We assessed energy balance via urinary C‐peptide concentrations (2717 urine samples), behavioral energy intake and expenditure (5728 sampling hours), and physiological energy expenditure via fecal triiodothyronine metabolites (fTH3; 3138 fecal samples).
Results
We found that energy balance varied among reproductive states: (a) cycling was a period of low C‐peptide concentrations; (b) the highest C‐peptide concentrations occurred during gestation; and (c) the beginning of lactation marked a notable decrease in C‐peptide concentrations, which then improved at mid‐lactation to again decline at lactation offset. These peaks and valleys in energy balance did not seem to be associated with variation in energy acquisition but were rather mirrored by activity levels and fTH3 during lactation.
Discussion
Energy balance was not preserved through the reproductive cycle, supporting previous contentions that the reproductive performance of female mantled howler monkeys may be energetically constrained. The contrast between these and results that we have previously reported, highlights the importance of conducting follow‐up studies to continually improve our understanding of the reproductive energetics of primate females.
Mantled howler monkey females do not preserve their energetic condition throughout the reproductive cycle. Lactating females, such as those depicted here, are generally in a lower condition than females in other states.
Anthropogenic noise is a major global pollutant but its effects on primates are poorly understood, limiting our ability to develop mitigation actions that favor their welfare and conservation. In ...this study, we used an experimental approach to determine the impact of variation in noise intensity on mantled howler monkeys (Alouatta palliata). We conducted the study at Los Tuxtlas (México), where we studied the physiological stress (proxied via fecal glucocorticoid metabolites, fGCM) and behavioral responses of 16 males. We played back chainsaw noise at two intensities (40 and 80 dB) and used days in which groups were not exposed to noise as matched controls. With increased noise intensity fGCM increased, vigilance and vocalizations were longer, and vigilance, vocalizations, and flight occurred quicker. Physiological and behavioral responses occurred even after low‐intensity noise playbacks (i.e., 40 dB). Therefore, noise intensity is a significant factor explaining the responses of mantled howler monkeys to anthropogenic noise. These results imply that management actions aimed at eradicating anthropogenic noise are required for the conservation and welfare of mantled howler monkeys at Los Tuxtlas.
The physiological and behavioral responses of mantled howler monkey males to anthropogenic noise are conditional on noise intensity.
Highlights
Anthropogenic noise is a major global pollutant but its effects on primates are poorly understood.
Noise intensity has strong effects on the physiological and behavioral responses of mantled howler monkeys to anthropogenic noise.
The influence of dietary crude protein (CP) levels on growth performance, morbidity, and estimated dietary net energy (NE) of light-weight crossbreed feedlot calves during a 35-d receiving period was ...evaluated. For the above, 108 crossbred steers (196±13 kg) were used in 35-d receiving trial. Steers were randomly allocated to 18 pens (6 steers/pen, 6 replicas/treatment). Treatments consisted of a steam flaked corn-based receiving diet (72:28 concentrate to forage ratio) containing 12.5, 13.5 and 14.5% CP. Crude protein level in diet was manipulated by replacing steam flaked corn by canola meal. Steers were allowed ad lib. access to their experimental diets. Morbidity averaged 32%, and was not affected by treatments. Increasing the level of dietary CP improved average daily weight gain, gain efficiency and tended to increase the ratio of observed-to expected dietary NE. Furthermore, in CP range from 12.5 to 13.5%, these effects were evident, but were not apparent at 13.5 to 14.5% CP. It can be concluded that high-energy receiving diet formulations containing 13.5 to 14.5% CP will optimise initial growth performance of light-weight (~200 kg BW) feedlot calves. However, present effect may be more a function of achieving metabolisable amino acid rather than metabolisable protein requirements.
Obsessive-compulsive disorder (OCD) is a common, debilitating neuropsychiatric illness with complex genetic etiology. The International OCD Foundation Genetics Collaborative (IOCDF-GC) is a ...multi-national collaboration established to discover the genetic variation predisposing to OCD. A set of individuals affected with DSM-IV OCD, a subset of their parents, and unselected controls, were genotyped with several different Illumina SNP microarrays. After extensive data cleaning, 1465 cases, 5557 ancestry-matched controls and 400 complete trios remained, with a common set of 469,410 autosomal and 9657 X-chromosome single nucleotide polymorphisms (SNPs). Ancestry-stratified case-control association analyses were conducted for three genetically-defined subpopulations and combined in two meta-analyses, with and without the trio-based analysis. In the case-control analysis, the lowest two P-values were located within DLGAP1 (P=2.49 × 10(-6) and P=3.44 × 10(-6)), a member of the neuronal postsynaptic density complex. In the trio analysis, rs6131295, near BTBD3, exceeded the genome-wide significance threshold with a P-value=3.84 × 10(-8). However, when trios were meta-analyzed with the case-control samples, the P-value for this variant was 3.62 × 10(-5), losing genome-wide significance. Although no SNPs were identified to be associated with OCD at a genome-wide significant level in the combined trio-case-control sample, a significant enrichment of methylation QTLs (P<0.001) and frontal lobe expression quantitative trait loci (eQTLs) (P=0.001) was observed within the top-ranked SNPs (P<0.01) from the trio-case-control analysis, suggesting these top signals may have a broad role in gene expression in the brain, and possibly in the etiology of OCD.
The relationship between a history of lifetime psychiatric disorders of parents with selective mutism (SM) in their children is examined. The results support earlier findings of a familial ...relationship between generalized social phobia and SM.
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