Primate

About: Primate is a research topic. Over the lifetime, 1250 publications have been published within this topic receiving 67388 citations. The topic is also known as: the primate order & primates.

ACE2 and TMPRSS2 variation in savanna monkeys (Chlorocebus spp.): Potential risk for zoonotic/anthroponotic transmission of SARS-CoV-2 and a potential model for functional studies.

Abstract: The COVID-19 pandemic, caused by the coronavirus SARS-CoV-2, has devastated health infrastructure around the world Both ACE2 (an entry receptor) and TMPRSS2 (used by the virus for spike protein priming) are key proteins to SARS-CoV-2 cell entry, enabling progression to COVID-19 in humans Comparative genomic research into critical ACE2 binding sites, associated with the spike receptor binding domain, has suggested that African and Asian primates may also be susceptible to disease from SARS-CoV-2 infection Savanna monkeys (Chlorocebus spp) are a widespread non-human primate with well-established potential as a bi-directional zoonotic/anthroponotic agent due to high levels of human interaction throughout their range in sub-Saharan Africa and the Caribbean To characterize potential functional variation in savanna monkey ACE2 and TMPRSS2, we inspected recently published genomic data from 245 savanna monkeys, including 163 wild monkeys from Africa and the Caribbean and 82 captive monkeys from the Vervet Research Colony (VRC) We found several missense variants One missense variant in ACE2 (X:14,077,550; Asp30Gly), common in Ch sabaeus, causes a change in amino acid residue that has been inferred to reduce binding efficiency of SARS-CoV-2, suggesting potentially reduced susceptibility The remaining populations appear as susceptible as humans, based on these criteria for receptor usage All missense variants observed in wild Ch sabaeus populations are also present in the VRC, along with two splice acceptor variants (at X:14,065,076) not observed in the wild sample that are potentially disruptive to ACE2 function The presence of these variants in the VRC suggests a promising model for SARS-CoV-2 infection and vaccine and therapy development In keeping with a One Health approach, characterizing actual susceptibility and potential for bi-directional zoonotic/anthroponotic transfer in savanna monkey populations may be an important consideration for controlling COVID-19 epidemics in communities with frequent human/non-human primate interactions that, in many cases, may have limited health infrastructure

Hair loss and hair-pulling in rhesus macaques (Macaca mulatta).

Abstract: Alopecia (hair loss) is a substantial problem in rhesus macaque colonies, with an estimated prevalence of around 48% of animals exhibiting it at some point in their history12 and with numbers reaching as high as 68% in some populations.20 Hair loss can range from small focal areas to whole body parts (for example, the back) to the entire body missing hair.9,11,19 Although alopecia is not an uncommon condition, its etiology is not fully understood, with many contributing factors including seasonal variation, aging, rank, sex, housing condition, reproductive state, skin disorders, and nutritional deficiencies, behavioral pathology, and stress.5,12,17,20,22 Little is known about the relative contribution of various factors to alopecia in colony primates, but the assumption has often been that alopecia is primarily the result of a particular behavioral pathology (that is, hair-pulling) or the stress of the captive environment. Whatever the cause, alopecia is often considered to be a sign of poor welfare and subjected to increased regulatory attention.1,13 Hair-pulling is a syndrome that includes plucking hair from the body by using hands or teeth, manipulating it, and frequently ingesting it.3,14,17,18 Methods of hair removal range from pulling out fistfuls of hair to plucking out single hairs at a time to overgrooming (self-grooming in excess), and the resulting coat can have bald or patchy patterns.8 In cases where excessive hair is ingested by monkeys, gastric trichobezoars (that is, hair balls) can result, potentially leading to serious clinical complications.16 The prevalence of hair-pulling in individually housed monkeys is about 14% and is associated with increased age,14 but a more recent study reported overall rates as high as 33%.13 This pattern of hair-pulling is similar to that observed in the human disorder trichotillomania which also involves plucking out, and sometimes ingesting, hair.6,23 People have reported that hair-pulling is sometimes associated with increasing tension or stress, which can be alleviated with the act of pulling out hair.6,21 However, in rhesus macaques, stress does not appear to be a factor in hair loss.12,13 The true relationship between hair-pulling and alopecia is currently unknown. Although it is likely that hair-pulling produces hair loss in some rhesus macaques, it is unlikely that all cases of hair loss are attributable to the hair-pulling syndrome. In one study, a significantly higher proportion of rhesus monkeys with alopecia were observed to hair pull (53.9%), but 12.8% of the control population (with less than 10% hair loss) were observed to hair-pull, and for animals with alopecia, the location of the hair-pulling was not always near the site of alopecia.13 In addition, one singly housed rhesus monkey developed gastric trichobezoars from hair eating but was reported to have a good coat of hair.16 Further complicating this relationship between hair-pulling and alopecia is social housing. Monkeys can pull their own hair or that of others (or both). In a study of 2 breeding groups of rhesus macaques, monkeys pulled hair at the rate of 2.4 episodes per hour, and most of the episodes were directed toward other monkeys rather than to self (97% compared with 3%, respectively).18 In addition, limited enclosure space appears to have an additional effect on hair loss in group-housed rhesus monkeys.5,19 The purpose of the current study was to examine the relationship between alopecia and hair-pulling behavior in individually housed rhesus macaques in 4 primate colonies across the United States. There were 3 objectives. The first objective was to characterize the prevalence of alopecia and hair-pulling by using a simple ‘yes–no’ scoring system, with any hair loss or observation of hair-pulling scored as ‘yes.’ In the second objective, we examined prevalence as a function of facility. Animal management practices vary quite widely across primate facilities2 and may differentially affect the extent of both alopecia and hair-pulling. Therefore, we assessed commonalities and differences in alopecia and hair-pulling across primate centers. The final objective was to determine whether hair-pulling was a primary factor of hair loss in individually housed monkeys.

Flexibility in positional behavior, strata use, and substrate utilization among Bale monkeys (Chlorocebus djamdjamensis) in response to habitat fragmentation and degradation.

Abstract: Studies of the effects of habitat fragmentation and degradation on primate positional behavior, strata use, and substrate utilization offer valuable insights into the behavioral and ecological flexibility of primates whose habitats have undergone extensive anthropogenic disturbance. In this study, we evaluated how positional behavior, strata use, and substrate utilization differed between Bale monkeys (Chlorocebus djamdjamensis)-bamboo-eating cercopithecids endemic to the southern Ethiopian Highlands-occupying continuous versus fragmented forests. Bale monkeys in forest fragments (where bamboo had been degraded or eradicated) spent significantly more time on the ground and in understory strata whereas those in continuous forest spent significantly more time in the middle and upper strata. Bale monkeys in forest fragments also spent significantly more time walking and galloping and significantly less time climbing than those in continuous forest. Our results suggest that, unlike the primarily arboreal Bale monkeys in continuous forest, Bale monkeys in forest fragments should be characterized as semi-terrestrial. In response to habitat disturbance in fragments, we observed a greater emphasis on terrestrial foraging and travel among Bale monkeys in these human altered habitats, which may put them at greater risk of predation and conflict with nearby human populations. Bale monkeys in fragments exhibit flexibility in their positional behavioral repertoire and their degree of terrestriality is more similar to their sister taxa in Chlorocebus than to Bale monkeys in continuous forest. These findings suggest that habitat alteration may compel Bale monkeys to exhibit semi-terrestrial behaviors crucial for their persistence in human-modified habitats. Our results contribute to a growing body of literature on primate behavioral responses to anthropogenic modification of their habitats and provide information that can contribute to the design of appropriate conservation management plans.