Impact of social environment on female chimpanzee reproductive cycles

The socio-sexual environment of a female is known to affect ovarian function. Increased male contact can enhance menstrual cycle regularity. Conversely, social deprivation constitutes a form of stress that often alters cyclicity and the secretion of reproductive hormones. The present study was carried out on captive female chimpanzees to examine possible interactions among housing conditions, menstrual cycle length, morphological changes in secondary sexual character expression and endocrine release patterns related to follicular and luteal function. Animals were housed over a period of 2 years either with a male conspecific or singly. Blood samples were collected over three cycles, and anogenital swelling changes registered to define menstrual cycle phases. Fecal sampling techniques were used to monitor cortisol as a measure of stress-load. Male presence seemed to affect female cyclicity. Females housed with a male had shorter and more regular cycles than singly housed females. Prolactin, gonadotropins and estradiol levels were generally higher in paired females during specific cycle phases. Group variation was not always significant. No differences were found in progesterone. Sexually cohabited females tended to have lower fecal cortisol metabolites immediately before and after maximum tumescence. We suggest that the close behavioral, physical and olfactory contact with a male conspecific can act as a sort of zeitgeber to modulate ovarian function by stabilizing the female cycle and, perhaps, enhancing folliculogenesis and ovulation.     

Comparative immobilization of wild felids in Thailand

We immobilized individuals of four free-ranging felid species, leopard cat (Prionailurus bengalensis), clouded leopard (Neofelis nebulosa), Asiatic golden cat (Catopuma temminckii), and marbled cat (Pardofelis marmorata) with ketamine hydrochloride and xylazine hydrochloride (KH-XH) and with tiletamine hydrochloride and zolazepam hydrochloride (TH-ZH) between March 1998 and July 2002. Mean (+/-SD) dose of KH and XH was 26.51+/-5.71 mg/kg and 1.89+/-0.43 mg/kg, respectively (n=25), and mean dose of TH-ZH was 11.61+/-3.39 mg/kg (n=28). Dose was significantly correlated with induction time (P<0.001) and duration of anesthesia (P<0.05), but not with recovery time. There were significant differences between the drug combinations in time to induction (P<0.03) and time to anesthesia (P<0.01); recovery times were not significantly different. We conclude that immobilization of these felids with TH-ZH and KH-XH is effective and safe, but TH-ZH is preferred because of the smaller volume of drug necessary for sedation, faster time to induction, and absence of prolonged muscle rigidity during anesthesia.     

The AB blood group system in wild felids

The blood type of 131 non-domesticated felids belonging to 26 felid species was surveyed in this study. Based upon a tube hemagglutination assay established for domestic cats, 80% of felids had type-A, 18% type-B, and 2% type-AB blood. Felids in the Puma group and African and Asian golden cats had blood type B, whereas all other species were found to have blood type A. Two cheetahs and one bobcat had type-AB blood. Red cell glycolipids analysed by high performance thin layer chromatography revealed a similar ganglioside pattern in wild cats as reported in domestic cats. Independent of the AB blood group system, incompatible blood crossmatch reactions were detected between different felid groups. In conclusion, wild felids display the same AB-erythrocyte antigens as domestic cats, and the same blood typing procedures can be applied for wild and domestic felids.     

Activity budgets of wild female chimpanzees in different reproductive states

Activity budgets of wild female chimpanzees (Pan troglodytes schweinfurthii) when lactating were compared with those during estrus and anestrus. Five anestrous females, seven estrous females, and three lactating females in Mahale Mountains National Park, Tanzania, were the subject of focal sampling. Time spent for feeding, resting, and moving was examined. For each of these three categories of activity, there was no significant difference of time spent for each activity between lactating females and either estrous or anestrous females. The females spent about 30% of their daytime feeding, about 40% resting, and about 30% moving. One of the reasons for the lack of difference might be the type of parties that females attended when they were observed. In most cases, the females were seen in large bisexual parties. Although lactating females are expected to need more nutrition than cycling females and this might affect their activity budget, the party type they attended might also affect the budget. Received: January 17, 2000 / Accepted: June 22, 2000     

Female coloration indicates female reproductive capacity in blue tits

It is poorly understood whether female morphological and behavioural traits can be used as 'signals'. In particular, experimental tests of the hypothesis that female ornaments reflect quality are scarce. Here, we experimentally examine whether female plumage coloration might signal maternal quality in the blue tit, Cyanistes caeruleus by forcing half of the females breeding in our population to produce a replacement clutch. Using statistical models that controlled for the effects of male coloration, and the effects of age and condition of both parents, we found that carotenoid-based female coloration was positively linked to key proxies of bird lifetime reproductive success: clutch size, fledgling success and recruitment. Importantly, the relationships between maternal yellow carotenoid coloration and both clutch size and recruitment were stronger in the experimental group than in the control group, indicating that breeding females with higher values of yellow coloration were better able to handle the cost of producing a second clutch. Finally, UV-blue female coloration was positively linked to female survival and marginally linked to laying date. Taken together, these results show for the first time in a natural population that female coloration can indicate individual and maternal quality under natural and adverse reproductive conditions. They highlight the potential for the evolution of female ornamental traits through sexual selection.     

Female reproductive cycles in two subspecies of the tropical lizard Mabuya striata

Summary Female reproductive cycles were examined in two subspecies of the live-bearing lizard Mabuya striata from Central Africa, an area with distinct rainy and dry seasons. The low altitude M. s. striata was reproductive throughout the year apart from a brief period at the start of the rainy season, and probably produced three clutches a year. Most females of the high altitude M. s. punctatissima were non-reproductive in the rainy season, came into reproductive condition in the early dry season, and gave birth in the late dry season. For some females, there was a second reproductive cycle starting in the late dry season with birth in the rainy season. For the low altitude M. s. striata it appears that availability of moisture may affect reproduction. For the high altitude M. s. punctatissima it appears that the low temperatures and short hours of sunshine of the early dry season constrain reproduction, and that reproductive cycles are timed to avoid birth occurring in the early dry season.     

Female reproductive cycles and birth data from an Old World Monkey colony

Observations on reproductive cycles and births for a variety of captive Old World monkey species are reported. The majority of the subjects have been group living animals, housed with conspecifics in large outdoor compounds. Reproductive cycles were measured by notation of changes in the degree of female sex skin swellings. Three types of cycles are distinguished: estrus, intrapregnancy, and pubertal. Cycle length periods and the duration of the period of swelling are described for each cycle type. Birth distributions are analyzed for the occurrence of seasonality, and a marked seasonal effect tied to the onset of cycling in pubescent females is noted. The influence of a group formation effect on the timing of the reproductive season in one species is discussed.     

DNA extraction from hair shafts of wild Brazilian felids and canids

Wild felids and canids are usually the main predators in the food chains where they dwell and are almost invisible to behavior and ecology researchers. Due to their grooming behavior, they tend to swallow shed hair, which shows up in the feces. DNA found in hair shafts can be used in molecular studies that can unravel, for instance, genetic variability, reproductive mode and family structure, and in some species, it is even possible to estimate migration and dispersion rates in given populations. First, however, DNA must be extracted from hair. We extracted successfully and dependably hair shaft DNA from eight wild Brazilian felids, ocelot, margay, oncilla, Geoffroy's cat, pampas cat, jaguarundi, puma, and jaguar, as well as the domestic cat and from three wild Brazilian canids, maned wolf, crab-eating fox, and hoary fox, as well as the domestic dog. Hair samples came mostly from feces collected at the S?o Paulo Zoo and were also gathered from non-sedated pet or from recently dead wild animals and were also collected from museum specimens. Fractions of hair samples were stained before DNA extraction, while most samples were not. Our extraction protocol is based on a feather DNA extraction technique, based in the phenol:chloroform:isoamyl alcohol general method, with proteinase K as digestive enzyme.     

A serologic survey of wild felids from central west Saudi Arabia

Forty-five wildcats (Felis silvestris), 17 sand cats (Felis margarita), and 17 feral domestic cats were captured in central west Saudi Arabia, between May 1998 and April 2000, with the aim to assess their exposure to feline immunodeficiency virus/puma lentivirus (FIV/PLV), feline leukaemia virus (FeLV), feline herpesvirus (FHV-1), feline calicivirus (FCV), feline coronavirus (FCoV), and feline panleukopenia virus (FPLV). Serologic prevalence in wildcats, sand cats, and feral domestic cats were respectively: 6%, 0%, 8% for FIV/PLV; 3%, 8%, 0% for FeLV; 5%, 0%, 15% for FHV-1; 25%, 0%, 39% for FCV; 10%, 0%, 0% for FCoV; and 5%, 0%, 8% for FPLV. We recorded the first case of FeLV antigenemia in a wild sand cat. Positive results to FIV/PLV in wildcats and feral cats confirmed the occurrence of a feline lentivirus in the sampled population.     

Spatial organization of felids populations and some traits of their reproductive strategies

In all Felidae species, females are able to mate with several males during the estrus. Promiscuity mating system is the most typical of the solitary living species that have large home ranges. Females are usually widely distributed over the area and males move actively searching for the receptive females and defending them during the estrus period. Mating with few males is usually considered as a possibility to improve the quality of the offspring. In this article, some characteristics of home range use, marking and acoustic activity, traits of physiology which may result in promiscuity mating in felids are considered. An adaptive significance of mating few males is also discussed.     

Seroprevalence of six reproductive pathogens in European wild boar (Sus scrofa) from Spain: the effect on wild boar female reproductive performance

We studied the seroprevalence of six reproductive pathogens in Spanish hunter-harvested wild boar females. The sample was representative of the hunting harvest in the studied hunting estates. Mean antibody prevalences were: 60.6+/-0.06% for Aujeszky's disease virus (ADV), 56.6+/-0.09% for porcine parvovirus (PPV), 51.8+/-0.06% for porcine circovirus type 2 (PCV2), 29.7+/-0.09% for Brucella spp. and 36.3+/-0.1% for Toxoplasma gondii. We did not detect antibodies against porcine reproductive and respiratory syndrome virus (PRRSv). ADV seroprevalence was associated with PPV and PCV2 seroprevalence in Spanish wild boar females. Ovulation rate in the studied wild boar females was 4.41+/-0.16 (n=120), mean litter size was 3.91+/-0.16 (n=82) and the partial resorption index 0.92+/-0.17 (n=66). Ovulation rate and litter size were statistically associated with age. T. gondii seroprevalence was negatively related to ovulation rate and partial resorption index. Wild boars from managed fenced estates had antibodies against more pathogens than wild boars from open estates. Potential relations between management of wild boar populations and exposure of individuals to different reproductive pathogens are discussed.     

Testosterone and cortisol concentrations vary with reproductive status in wild female red deer

Although hormones are key regulators of many fitness and life history traits, the causes of individual level variation in hormones, particularly in wild systems, remain understudied. Whilst we know that androgen and glucocorticoid levels vary within and among individuals in mammalian populations, how this relates to key reproductive processes such as gestation and lactation, and their effects on a female''s measurable hormone levels are poorly understood in wild systems. Using fecal samples collected from females in a wild red deer population between 2001 and 2013, we explore how fecal androgen (FAM) and cortisol (FCM) metabolite concentrations change with age and season, and how individual differences relate to variation in reproductive state. Both FAM and FCM levels increase toward parturition, although this only affects FCM levels in older females. FCM levels are also higher when females suckle a male rather than a female calf, possibly due to the higher energetic costs of raising a son. This illustrates the importance of accounting for a female''s life history and current reproductive status, as well as temporal variation, when examining individual differences in hormone levels. We discuss these findings in relation to other studies of mammalian systems and in particular to the relatively scarce information on variation in natural levels of hormones in wild populations.     

Ovarian control for assisted reproduction in the domestic cat and wild felids

Of the 37 felid species, all but the domestic cat are classified as threatened with extinction in all or part of their native range. Additionally, the domestic cat is a valuable model for human biomedical research. Propagating some wild felids as well as domestic cat populations serving as human models is a major challenge primarily due to difficulties in transporting animals between facilities to ensure the pairing of genetically matched individuals, behavioral incompatibility between pairs and low fertility. Artificial insemination (AI) and in vitro fertilization/embryo transfer (IVF/ET) are powerful tools for helping manage rare populations. Developing successful assisted reproductive techniques requires knowledge of the female reproductive cycle and precise control of ovarian activity. Successful ovarian stimulation for AI and IVF/ET has been achieved in at least one-third of all cat species. However, sensitivity to a given gonadotropin treatment appears highly species-specific, and poor responses are common, particularly in felid species that exhibit spontaneous ovulations. Furthermore, current gonadotropin regimens have been demonstrated to perturb female reproductive function often leading to reduced fertility. Overall, ovarian response to exogenous hormonal stimulation has been highly variable, and pregnancy success after AI or IVF/ET remains low (<20%) in most species. Therefore, there is an immediate need to develop improved regimens that would allow more predictable ovarian responses in felids. We contend that recent research involving the use of progestins to control the ovary prior to gonadotropin stimulation shows promise for providing consistent ovarian stimulation in felids.     

The impact of ecological variability on the reproductive endocrinology of wild female African elephants

Non-invasive endocrine methods enable investigation of the relationship between ecological variation and ovarian activity and how this impacts on demographic processes. The underlying physiological factors driving high variation in inter-calving intervals among multi-parous African elephants offer an interesting system for such an investigation. This study investigates the relationship between Normalized Differential Vegetation Index (NDVI), an ecosystem surrogate measure of primary productivity, and fecal progestin concentrations among wild female elephants. Matched fecal samples and behavioral data on reproductive activity were collected from 37 focal individuals during the two-year study. Linear mixed models were used to explore the relationship between fecal 5alpha-pregnane-3-ol-20-one concentrations and the independent variables of NDVI, calf sex, female age, gestation day, and time since last parturition. Among both non-pregnant and pregnant females, fecal 5alpha-pregnane-3-ol-20-one concentrations were significantly correlated with time-specific NDVI indicating a strong relationship between ecological conditions and endocrine activity regulating reproduction. In addition, the age of a female and time since her last parturition impacted hormone concentrations. These results indicate that the identification of an individual's reproductive status from a single hormone sample is possible, but difficult to achieve in practice since numerous independent factors, particularly season, impact fecal hormone concentrations. Regardless of season, however, fecal 5alpha-pregnane-3-ol-20-one concentrations below 1 microg/g were exclusively collected from non-pregnant females, which could be used as a threshold value to identify non-pregnant individuals. Collectively the information generated contributes to a better understanding of environmental regulation of reproductive endocrinology in wild elephant populations, information salient to the management and manipulation of population dynamics in this species.     

Semi-monthly reproductive cycles in male and female fiddler crabs, Uca pugnax

In the fiddler crab, Uca pugnax, numbers of displaying males, numbers of burrows with half-dome superstructures (hoods), numbers of females with decalcified vulvar opercula, and numbers of females hatching their eggs, all follow a semi-monthly cycle with peaks near the time of the spring tides. These are all aspects of reproduction in Uca. Decalcification of female opercula, although necessary for mating and egg deposition, is neither necessary nor sufficient for behavioural response to courting males. In fact, behavioural responsiveness to males probably precedes decalcification in most cases. The different aspects of the reproductive cycle are coordinated so that females and males are ready to mate at about the same time near one spring tide, and the resulting eggs will be ready to hatch on the next spring tide. Two decalcified females which were kept isolated from males produced fertile clutches, suggesting that stored sperm from a previous mating may fertilize eggs in a later cycle. This may be one reason for the relative rarity of observed matings or precopulatory behaviour in Uca.     

Hormonal correlates of reproductive seasonality in wild female hanuman langurs (Presbytis entellus)

To date, it is not known whether the seasonal occurrence of sexual behavior and mating in free-ranging Hanuman langurs at Ramnagar, Nepal, is correlated with seasonal changes in female ovarian function, and, if so, which factor(s) triggers the onset of the reproductive period. Using noninvasive fecal hormone analysis in combination with behavioral observations, this study was carried out to: 1) investigate and characterize seasonal patterns of ovarian cyclicity and timing of conception in wild langur females living in a highly seasonal habitat; and 2) examine the relationship between seasonal patterns of ovarian cyclicity, behavioral estrus, and female physical condition. Behavioral data and fecal samples were collected during a total period of 14 months from nine females living in a multi-male group. Physical condition of the females was assessed monthly by visual inspection, using a seven-fold scale. Ovulatory cycles and timing of conceptions were identified by the measurement of immunoreactive pregnanediol glucuronide (iPdG) in extracted feces. Hormone profiles in individual females revealed a clearly seasonal distribution in the occurrence of ovulatory cycles, which were restricted to the period from July to October. The distribution of female estrus behavior showed a similar seasonal pattern, and in total 88.2% of all estrus periods observed in the focal females were accompanied by ovulation. Onset of ovarian cycles as well as mating activities were strongly correlated with the onset of the rainy season. Females conceived, on average, in their second ovulatory cycle (pregnancy length: 211.6 +/- 3.4 days), with timing of conception being confined to the months when animals showed an improved physical condition. Collectively the present data clearly suggest that in seasonally-breeding langurs at Ramnagar, ecological conditions (rainfall, food availability, and quality) influence the onset of ovulations and timing of conceptions.