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1.
Groundnut samples from 21 selected markets in the 10 regions of Ghana yielded high levels of the aflatoxigenic fungus Aspergillus flavus on half-strength potato dextrose agar. The fungus was associated with 31.7 and 12.8%, respectively, of all damaged and undamaged kernels assayed. Only 0.24% of total kernels assayed yielded A. parasiticus. Other fungi detected from total kernels assayed were A. niger (34%), A. candidus (1.45%), A. tamarii (3.93%), A. ochraceous (5.26%), Fusarium spp. (1.7%) Penicillium spp. (5.19%), a Mucor sp. (2.3%), a Trichoderma sp. (0.2%), Rhizopus stolonifer (12%) and certain unidentifiable fungi (11.72%). Total aflatoxin levels ranging from 5.7 to 22, 168 ppb were identified with damaged kernel samples. The mycotoxin was not detected in 50% of undamaged kernel samples tested and very low levels mostly ranging from 0.1 to 12.2 ppb were associated with the undamaged samples that tested positive for aflatoxins. In a novel in vitro microbial assay to determine the effectiveness of certain plant extracts against aflatoxin synthesis, extracts from Xylopia aethiopica, Monodera myristica, Cinnamomum verum and Piper nigrum permitted fungal growth in 1.5% potato-dextrose broth while completely suppressing NOR formation. These extracts, however, could not suppress NOR formation in a yeast extract sucrose medium. 相似文献
2.
Dirks W Humphrey LT Dean MC Jeffries TE 《Folia primatologica; international journal of primatology》2010,81(4):207-223
Weaning conflict may represent an evolutionary conflict of interest between parent and offspring, an honest signal of need on the part of a weanling, or both. Accentuated lines visible in histological sections of teeth are indicators of stress during enamel formation and have been hypothesised to form in baboon teeth during weaning. We analysed growth increments in 5 tooth sections from 2 Ugandan baboons (Papio hamadryas anubis), using polarised light microscopy, to determine when stresses occurred during the weaning process. Dietary transitions were reconstructed using normalised strontium intensities (Sr/Ca) in enamel. Accentuated lines were cross-matched between teeth from the same animal and plotted by month. The highest frequency of stress was experienced at around 6 months in 1 baboon, coinciding with an inferred reduction in suckling frequency, and at 11 months in another, coinciding with the inferred cessation of suckling. Because accentuated lines appear to indicate weaning stress at dietary transitions, weaning conflict may represent an honest signal of need on the part of the weanling. 相似文献
3.
Robert M. Sapolsky 《American journal of primatology》1986,11(3):217-227
As part of a long-term study in behavioral endocrinology, wild olive baboons (Papio anubis) living in the Serengeti ecosystem of East Africa have been under study since 1978. The present report documents behavioral and endocrine changes associated with the severe drought of 1984. During this time, the annual rainy season failed and grassland biomass was severely reduced in the Serengeti. Baboons were able to maintain body weight but spent significantly more time foraging for food. In four prior years of study, basal testosterone concentrations were remarkably stable in adult and subadult males. In contrast, during the drought, there was a highly significant 60% decline in basal concentrations of the steroid. This testicular suppression was apparent in males of all ranks (by approach-avoidance criteria). Prior studies with this population, which examined the role of acute and chronic stressors in similarly suppressing testosterone concentrations, suggested that the present instance was in response to the stress of the drought. The drought was also associated with significant reductions in the rates of escalated aggression among males. However, the distribution of fights between high-ranking males, between low-ranking males, and between high- and low-ranking males did not change from prior years, nor was the dominance hierarchy inordinately unstable during this time. These findings agree with previous evidence that indicates that suppressed testosterone concentrations in males can be associated with lower rates of aggressive behaviors but that the steroid plays a predominantly facilitative rather than activational role. Finally, rates of approach-avoidance interactions and of male sexual behaviors were unchanged during the drought. These findings agree with an endocrine literature that indicates that reproductive behavior or physiology in primates is rarely disrupted by suppression of testosterone concentrations of the magnitude of the present case. 相似文献
4.
Jane E. Phillips-Conroy Clifford J. Jolly 《American journal of physical anthropology》1981,56(2):115-129
Sexual dimorphism in mammals has been related to such variables as absolute body size, ecology, and various aspects of social behaviour. Attempts to relate dimorphism to any of these variables have necessarily used small heterogeneous samples to represent the relevant species. We are concerned by the inevitable exclusion of any measure of variability in dimorphism and the consequent impossiblity of assessing the significance of observed interspecific differences. In this paper we describe aspects of sexual dimorphism in anubis,hamadryas, and hybrid baboons from Ethiopia. Samples are large enough to permit a measure of intrapopulation variability. Hamadryas baboons are more dimorphic than anubis in epigamic features, but not in postcanine dentition, nor, contrary to previous reports, in body weight or canine tooth size. Hybrid males are more hamadryas-like and hybrid females more anubis-like, as would be predicted by the proposed mechanism for the establishment of the hybrid zone, namely the capture of anubis females by hamadryas males. 相似文献
5.
Fred B. Beicovrtch 《American journal of primatology》1987,12(2):189-195
The study reported here tested Altmann's prediction [Baboon Mothers and Infants. Cambridge, Harvard University Press, 1980] that lactating female baboons endure a weight loss. Data from 64 adult female olive baboons (Papio anubis) residing in six troops in Kenya revealed that reproductive condition was related to weight. Lactating females weighed less and pregnant females weighed more than cycling females. There was a negative correlation between the weight of cycling females and the number of months postweighing to their next conception. These results indicate that lactation in wild baboons imposes energy costs that result in lost weight. It is suggested that female baboons may have to surpass a minimum weight threshold prior to resumption of postlactational cycling and that nutritional status is more influential than rank in affecting female reproductive success. 相似文献
6.
G V Katsiia T N Todua V M Gorlushkin A M Chirkov N P Goncharov 《Biulleten' eksperimental'no? biologii i meditsiny》1989,107(2):231-234
The plasma levels of luteinizing hormone (LH) and testosterone were studied in intact and castrated male baboons exposed to 2- and 10-hour periods of immobilization. Presented data have shown that immobilization stress induced a marked decrease in LH concentration both in intact and castrated monkeys. Changes in LH concentration positively correlated with plasma levels of testosterone only during the experimental procedures. During three days after immobilization there was a sharp dissociation in the dynamics of testosterone levels remained low and LH returned to normal values. We can suggest that it is not absolute LH level that is responsible for the changes in testosterone secretion during the immobilization stress. 相似文献
7.
In past research on human and nonhuman primates, maternal responsiveness and behavior has been thought of as an experiential, cognitive mechanism; however, recent findings have shown that maternal motivation and behavior may not be entirely divorced from the endocrine system. To investigate the relationship between interest in infants and the hormonal changes related to pregnancy, we examined the nature of social interactions across parturition between a large sample (n = 133) of adult female baboons (Papio hamadryas anubis sp.) and unrelated infants. Prepartum data were collected during ten 30-min focal observations for each subject. Each mother-infant pair was then observed through the infant's first 8 weeks of life. A total of 2325 h of observation was recorded. Urine was collected on 65 subjects, starting 5 weeks before the expected date of parturition and ending 4 weeks after parturition. Evidence for a connection between endocrine function and responsiveness toward infants was found. Affiliative behaviors during the prepartum period were positively correlated to the estrogen/cortisol ratio and high dominance rank. In the postpartum period, affiliative behaviors were positively correlated with prepartum progesterone and dominance rank, and negatively correlated with postpartum cortisol levels. Finally, a positive correlation was recorded during the postpartum period between prepartum progesterone and aggression, and a negative correlation between postpartum cortisol and aggression and submission. Our data suggest that the endocrine changes that may help regulate maternal care of offspring also influence the way in which pre- and postpartum female baboons interact with unrelated infants in their social group. 相似文献
8.
The presence of human immunodeficiency virus (HIV) in genital secretions is regarded as a risk factor for sexual and perinatal transmission of HIV. A better understanding of correlates of genital shedding of HIV is crucial to the development of effective strategies against transmission of this virus. Events during menstrual cycle are likely to influence local immune responses and viral load in genital secretions, and hence determine susceptibility to HIV or efficiency of virus transmission. We report, in this study, preliminary findings on the relationship of menstrual cycle to genital mucosal and systemic immunity in female olive baboons (Papio anubis) experimentally inoculated with simian/human immunodeficiency virus (SHIV)89.6P. 相似文献
9.
Yellow baboons (Papio hamadryas cynocephalus) from Mikumi National Park, Tanzania were studied for polymorphisms in nuclear DNA. The study population consists of four social groups that inhabit overlapping home ranges and exchange males. As a result, these groups are considered to be members of a single interbreeding population. Human DNA clones were used as probes to screen five loci (AT3, REN, HEXB, VIM, and APOB) for restriction fragment length polymorphisms (RFLP). A total of 14 polymorphisms, at least one at each locus, was detected in a panel of 27 baboons tested using six restriction enzymes for each locus. Eleven of these RFLP systems have average heterozygosity values greater than 0.40. This initial screening demonstrates that human DNA clones can be used to detect significant numbers of informative DNA polymorphisms in single-copy nuclear genes of this species and suggests that the average proportion of nucleotides polymorphic across nuclear loci in this population may be between 1.0% and 1.3%. © 1993 Wiley-Liss, Inc. 相似文献
10.
Asgerally T. Fazleabas Sheri Hild-Petito Harold G. Verhage 《Cell biology international》1994,18(12):1145-1154
The primate endometrium undergoes distinct morphological changes during the menstrual cycle. These alterations are regulated by the steroid hormones, estrogen and progesterone. Several lines of evidence suggest that some of these hormonally induced changes may be modulated by growth factors. Our studies have focused on characterizing the secretory activity of the uterine endometrium associated with these hormonally regulated morphological changes during the menstrual cycle and pregnancy in the baboon. Additionally, we have also attempted to study the regulation of specific growth factors and their receptors. In this review we present evidence to indicate that growth factor receptors for insulin-like growth factor-I (IGF-I) and epidermal growth factor (EGF), and secretory proteins, insulin-like growth factor binding protein-1 (IGFBP-1) and retinol binding protein (RBP), which are present in the glandular epithelium during the menstrual cycle, undergo cell-specific changes in gene expression at the implantation site during pregnancy. We postulate that these alterations in growth factor receptor and secretory protein expression are conceptus modulated and may play important regulatory roles during trophoblast invasion and decidualization. 相似文献
11.
M. D. Rose 《American journal of physical anthropology》1976,44(2):247-261
The bipedal behavior of a troop of olive baboons (Papio anubis) is described. Bipedalism is relatively rare but nevertheless occurs in a wide variety of situations, although bipedalism during feeding occurs much more frequently than in other situations. The incidence of bipedalism varies between different age-sex classes and between individuals within age-sex classes. This pattern of bipedalism occurred within an overall adaptive response, particularly in feeding behavior, which was similar to that of the gelada baboon (Theropithecus gelada). The data on bipedalism is used together with an existing model of early hominid differentiation based on T. gelada to indicate the types of bipedal behavior which might have occurred in early hominid small object feeders and to suggest how a bipedal pattern of this type might have served as a basis for the action of selection for a more committedly bipedal pattern at later stages of hominid evolution. 相似文献
12.
Female reproductive cycles and the sexual behavior of moor macaques (Macaca maurus) in their natural habitat,South Sulawesi,Indonesia 总被引:1,自引:0,他引:1
Shuichi Matsumura 《Primates; journal of primatology》1993,34(1):99-103
The female reproductive cycles and sexual behavior of moor macaques (Macaca maurus) were studied in their natural habitat. Female moor macaques showed repeated perineal swelling. The average cycle length
was 36.2 days and the mean duration of swelling was 11.9 days. The estimated duration of gestation in two observed cases was
175 and 176 days, respectively. Females did not exhibit post-conception sexual swelling. Males appeared to ejaculate in multi-mounts.
Serial mounting by the alpha male was concentrated on swelling females, while second- and third-ranking males sometimes mounted
non-swelling females in series. 相似文献
13.
S. L. Monfort S. K. Wasser K. L. Mashburn M. Burke B. A. Brewer S. R. Creel 《Zoo biology》1997,16(6):533-548
The purpose of this study was to validate noninvasive endocrine monitoring techniques for African wild dogs (Lycaon pictus) and to establish physiological validity of these methods by evaluating longitudinal reproductive-endocrine profiles in captive individuals. To determine the primary excretory by-products of ovarian steroid metabolism, [14C]-progesterone and [3H]-estradiol were co-administered to a female and all excreta were collected for 80 hr postinjection. Radiolabel excretion peaked ≤ 18 hr postinfusion, and progesterone and estradiol metabolites were excreted in almost equivalent proportions in urine (39.7 and 41.1%, respectively) and feces (60.3 and 58.9%, respectively). Most of the urinary metabolites were conjugated (estradiol, 94.3 ± 0.3%; progesterone, 90.4 ± 0.5%), so that immunoassays for pregnanediol-3α-glucuronide (PdG) and estrogen conjugates (EC) were effective for assessing steroid metabolites. Two immunoreactive estrogens (estradiol and estrone) and at least one immunoreactive progesterone metabolite (3α-hydroxy-5α, pregnan-20-one) were detected in feces. Urine and fecal samples were collected (1–3 times per week) for 1.5 yr from one adult female and two adult males to assess longitudinal steroid metabolite excretion. Overall correlation of urinary PdG to matched, same-day fecal progesterone metabolites immunoreactivity was 0.38 (n = 71, P < 0.05). Similarly, urinary EC was correlated (P < 0.05) with same-day fecal estrogen immunoreactivity (r = 0.49, n = 71). During pregnancy and nonpregnant cycles, copulation occurred at the time of peak (or declining) estrogen metabolites and increasing progesterone metabolites concentrations. Estrus duration was 6–9 days and gestation lasted 69 days with parturition occurring coincident with a drop in progesterone metabolites. Males exhibited seasonal trends in fecal testosterone excretion with maximal concentrations from July to September coincident with peak mating activity. Although these limited longitudinal hormone profiles should be interpreted cautiously, noninvasive gonadal steroid monitoring suggests that: (1) both female and male wild dogs may exhibit reproductive seasonality in North America, (2) females are monoestrous, and (3) peak testicular activity occurs between August and October coincident with mating behavior. From a conservation perspective, noninvasive endocrine monitoring techniques should be useful for augmenting captive breeding programs, as well as for developing an improved understanding of the physiological mechanisms underlying reproductive suppression in response to social and ecological pressures. Zoo Biol 16:533–548, 1997. © 1997 Wiley-Liss, Inc. 相似文献
14.
Multilocus DNA fingerprinting was carried out on 65 individuals from a captive colony of guinea baboons (Papio hamadryas papio) at Brookfield Zoo, in order to determine the allocation of reproductive success among 7 active males. DNA fingerprinting
was found to reveal very low levels of genetic variability in the study population, rendering discrimination of different
levels of relatedness, and hence paternity, impossible. A method was therefore developed for emphasizing the region of the
fingerprint pattern which revealed the greatest level of band variability, and the effect of this experimental modification
on band sharing statistics was tested. Band sharing coefficients among unrelated individuals were significantly lower using
the modified system, which was then applied to paternity testing in the whole population. However even when using the modified
system, of the 33 offspring analyzed only 4 could be assigned solely to 1 male, 14 offspring were assigned to 1 of 2 males,
7 offspring had 3 potential fathers, and the remainder had 4 or more possible fathers. The implications of the limitations
of these data for behavioural studies and genetic management of captive populations are discussed. 相似文献
15.
S. E. Shideler A. Savage A. M. Ortuno E. A. Moorman B. L. Lasley 《American journal of primatology》1994,32(2):95-108
A simple method for extracting and measuring ovarian steroids in feces is applied to the ovarian cycle, pregnancy, parturition, and period of lactational amenorrhea in Pithecia pithecia. Small amounts of wet, unmixed feces were combined with a modified phosphate buffer, shaken, centrifuged, and decanted, and the supernatant was directly measured for estrogen and progesterone metabolites by enzyme immunoassays. Urinary estrogen and progesterone metabolite measurements were compared to paired fecal measurements to determine the degree to which fecal hormone levels detected the same ovarian events as urinary measurements. The correlation coefficients for the relationship between urinary and fecal hormones for individual animals studied (n = 5) were found to be statistically significant in every case except one sexually immature animal. The application of the method presented here demonstrates that simple solubilization and non-radiometric measurement of ovarian steroids excreted in feces reliably reflect reproductive events in Pithecia pithecia. © 1994 Wiley-Liss, Inc. 相似文献
16.
17.
In mammals, which give birth to more or less dependent offspring, parturition usually takes place during the animals' resting period and in a secure environment. We report here the first direct and documented observation of a daytime birth of a wild baby crested black macaque, Macaca nigra, in the Tangkoko Batuangus Nature Reserve, North Sulawesi, Indonesia. We further consider the parturition time as a female reproductive strategy in a broader evolutionary framework. 相似文献
18.
19.
Plant size,breeding system,and limits to reproductive success in two sister species of Ferocactus (Cactaceae) 总被引:1,自引:0,他引:1
Plant reproductive output can be limited by a variety of factors, bothintrinsic and extrinsic. I investigated the reproductive biologies of twospecies of unbranched short-columnar cacti, Ferocactuscylindraceus and F. wislizeni. I recordedfemalereproductive output (flowers produced, fruit set, seeds per fruit and seedmass), plant size and growth, and used hand-pollination experiments todeterminebreeding systems and pollen limitation. In both species, the ability to selfvaried among individuals, but self-pollination resulted in very few seeds,suggesting strong inbreeding depression. Neither species was pollen-limited.Numbers of flowers produced increases with plant size for both species, andseeds per fruit may also be related to plant size, although the relationship isunclear. Seed mass is not correlated with plant size. Flower production wassimilar in both species, but F. cylindraceus producedfewerseeds per fruit than F. wislizeni, and its seeds weighedless. Fruit set by F. cylindraceus was heavily impacted bya florivorous lepidopteran. Fruit set was very high (94 to 96%) inF. wislizeni, suggesting that architectural constraints(e.g., meristem limitation) are more limiting than resource levels or the levelof pollinator services. In F. cylindraceus, numbers ofseeds per fruit was positively correlated with seed mass, whereas inF. wislizeni, the relationship was negative (tradeoff).Thegrowth rates of F. wislizeni are affected by rainfall theprevious season, and growth rates increase as the plant ages.Ferocactus cylindraceus and F.wislizeni are thought to be sister species, meaning that observeddifferences between them are more likely to be the result of recentevolutionaryprocesses in their lineages rather than differing phylogenetic histories. 相似文献
20.
The biological containment of the potato (Solanum tuberosum) was assessed by establishing the crossability of this tuberous crop with the related wild non-tuberous species in The Netherlands, black nightshade (S. nigrum) and bittersweet (S. dulcamara). To circumvent crossability barriers, genotypes with different ploidy number were employed and crosses were performed under different environmental conditions. S. dulcamara was shown to be incongruent with potato at all ploidy levels, while S. nigrum displayed unilateral incompatibility. If S. nigrum was emasculated and used as female, fertilization by potato pollen resulted in berry set and seed development. Emasculation of S. nigrum was essential in this cross, because analysis of the fertilization process demonstrated that this species is highly self-compatible and potato pollen was outcompeted by pollen of S. nigrum. The hybrid seeds derived from this cross did not mature and appeared not to be viable. By application of the technique of embryo rescue of immature embryos, hybrid plants could be obtained. However, these hybrid plants proved to be sterile. These data demonstrate that gene flow by pollen dispersal from potato to its most common wild relatives in Western Europe is highly unlikely. The potato is thus a naturally contained species in this part of the world. 相似文献