Isolation of females prior to parturition reduces neonatal mortality in Galago

Eighteen years of birth records for three species of Galago at the Duke University Primate Center were examined to determine the effects of isolation of pregnant females on neonatal mortality rates. Isolation significantly decreased neonatal mortality rates in all three species over neonatal mortality rates in infants born to unisolated females. The frequency of cannibalism of infants did not differ between isolated and unisolated females. Secondary sex ratio differed significantly from 1:1 for all three species, but higher mortality in males in the first 10 days of life resulted in sex ratios that did not differ from 1:1 in G. garnettii and G. crassicaudatus.     

Lactation and interbirth interval in the Senegal galago (Galago senegalensis moholi)

Five years of reproductive data on Galago senegalensis moholi at the Duke University Primate Center were examined to determine the effect of lactation on interbirth interval and its component phases, postpartum anovulatory interval and interval from onset of estrous cycles to conception. Females whose infants died within 3 weeks of birth had significantly shorter interbirth intervals and postpartum anovulatory intervals than did females who raised their infants until weaning.     

Morphological clues to genetic species: multivariate analysis of greater Galago sibling species

Several studies conducted in diverse fields indicate the presence of a genetic discontinuity within the taxon Galago crassicaudatus E. Geoffroy--the thick-tailed bushbaby. One of these areas is morphology. This contribution details a statistical analysis of skull material classified under this taxon in order 1) to confirm the objective existence of two morphotypes, and 2) to investigate the characters that allow the skull types to be distinguished. Emphasis is placed on multivariate techniques, although univariate and bivariate techniques are included where they are felt to be appropriate. All statistical analyses point to the reality of the morphological discontinuity between the groups. This is true even when size considerations have been reduced by rescaling the data. The results support separation of the populations at a specific level: G. crassicaudatus and G. garnettii. In addition, the structural changes observed in the two taxa--including an increase in overall size in G. crassicaudatus--are indicative of a divergence in preferred habitats: G. garnettii is adapted to more mesic environmental conditions, and to a softer, less fibrous diet than is its more robust sibling.     

Aspects of reproduction and behavioral and vocal development in Senegal Bushbabies(Galago senegalensis)

Aspects of reproduction and development of the young in Galago senegalensiswere investigated as part of a long-term study of small groups which were housed at indoor and outdoor enclosures in southern Germany. Estrus and delivery of the young may occur in all months of the year. All of the 23 births recorded were singletons. Postpartum estrus is unusual; normally, females come into estrus 4 to 5 weeks after parturition. Gestation length was 141 ± 1.6 days measured from midestrus. Gravid females, or females with off-spring, were never separated from their family groups since the fathers and offspring from earlier litters were intensivly engaged in positive interactions with the growing young. The development of locomotion, social behavior, and vocal patterns from birth to nutritional weaning is described. Youngsters had specific vocalizations, which were, for the most part, different from those of adults. The results are compared with reproduction and behavioral ontogeny in related prosimian species.     

Effect of reproductive state and body size on food consumption in captive Galago senegalensis braccatus

Measurements of food consumption for different types of foods were made for seven Galago senegalensis braccatus. Differences because of reproductive state in females and body size were found. Lactating females consumed more food in total and had greater energy and protein intake than they did during other reproductive states. Near-term pregnant females consumed less food, energy, and protein than they did during other reproductive states. Body size affected food intake, with smaller animals ingesting more per unit metabolic weight than larger subjects.     

Reproductive patterns in galagos (Galago zanzibaricus and Galago garnettii) in relation to climatic variability

The reproductive patterns (birth seasonality, litter size, litters per year) of two sympatric species of galago (Galago zanzibaricus and G. garnettii) were studied in a coastal forest in Kenya for a two-year period. Trap-retrap and radio tracking methods were employed. G. zanzibaricus has one infant twice per year; G. garnettii has one infant once per year. Both species are seasonal breeders. These East African galagos are intermediate in reproductive patterns when compared with galagos from South African woodland (G. senegalensis moholi and G. crassicaudatus umbrosis) and West African rainforest (G. alleni and G. demidovii). Climatic patterns (total annual rainfall, seasonal variability of rainfall, variability in total annual rainfall, and annual temperature variability) are also compared for the three regions. Climatically, East Africa is intermediate between West and South Africa in total annual rainfall and in seasonality of rainfall, but not in year-to-year variability in rainfall. East Africa shows the highest variability in annual rainfall. South Africa has the coldest dry seasons and highest variability in temperatures. The results of this study suggest that “r-selection” and “K-selection” do not provide adequate explanations of galago reproductive patterns.     

Daytime variations of serum testosterone and luteinizing hormone in captive thick-tailed bush babies (Galago garnetti)

Mean daytime serum levels of testosterone (T) and luteinizing hormone (LH) were determined in eight male thick-tailed bush babies at different times of the day by radioimmunoassay and leydig cell bioassay respectively. Blood samples were obtained twice a week from each animal at different times of the day between 08:30 and 16:00. This was carried out for a period of eight weeks. There was significantly higher mean serum T levels in the morning compared to evening hours (p<0.05). There was no significant variation in mean serum LH levels, and no significant correlation between serum T and LH levels.     

Social organization of Galagos in Kenyan coastal forests: I. Galago zanzibaricus

The social organization of Galago zanzibaricus was studied for the first time and the study included data from two different sites in the coastal forests of Kenya. A combination of mark-recapture and radio-tracking techniques was used to investigate patterns of inter- and intrasexual home range overlap. Associations in sleeping groups indicated social ties between individuals. Patterns of range use were established by radio-tracking focal individuals. Adult males generally had nonoverlapping ranges, shared with one or two females and their offspring with which the male regularly slept. Young females remained longer in their natal ranges than males and reproduced within their natal ranges. Range size and distance traveled per night were similar between the sexes; both sexes probably defended territories. None of the other galago (bushbaby) species studied to date show the degree of close male-female association found in G. zanzibaricus. This study thus extends the variety of social organization documented in nocturnal prosimians.     

Fetal development in the normal thick-tailed bushbaby (Galago crassicaudatus panganiensis)

Fetal development was examined at days 60, 75, 90, 105, 120, or 135 of gestation in 19 thick-tailed bushbaby fetuses (Galago crassicaudatus panganiensis) from 17 normal, timed pregnancies. With the exception of day 135, all fetuses were collected by hysterotomy (gestation = 133 ± 2 days). Various weights and measurements were taken. Although fetal sizes varied widely, crown-rump, crown-heel, upper and lower arm and leg lengths, hand and foot lenghts, and fetal organ weights correlated well with fetal age. Key changes in gross brain morphology and skeletal ossification of cranium, pelvis, tarsals, carpals, and epiphyses were noted. Sternabrae ossification proved highly variable, while ossification in the otic capsule and associated ear structures correlated well with age. These data provide a normal base for studies using fetal developmental parameters whether the purpose is to determine gestational age or to design future studies.     

Vertical jumping in Galago senegalensis: the quest for an obligate mechanical power amplifier

Bushbabies (Galago senegalensis) are renowned for their phenomenal jumping capacity. It was postulated that mechanical power amplification must be involved. Dynamic analysis of the vertical jumps performed by two bushbabies confirms the need for a power amplifier. Inverse dynamics coupled to a geometric musculo-skeletal model were used to elucidate the precise nature of the mechanism powering maximal vertical jumps. Most of the power required for jumping is delivered by the vastus muscle-tendon systems (knee extensor). Comparison with the external joint-powers revealed, however, an important power transport from this extensor (about 65%) to the ankle and the midfoot via the bi-articular calf muscles. Peak power output likely implies elastic recoil of the complex aponeurotic system of the vastus muscle. Patterns of changes in length and tension of the muscle-tendon complex during different phases of the jump were found which provide strong evidence for substantial power amplification (times 15). It is argued here that the multiple internal connective tissue sheets and attachment structures of the well-developed bundles of the vastus muscle become increasingly stretched during preparatory crouching and throughout the extension phase, except for the last 13 ms of the push-off (i.e. when power requirements peak). Then, tension in the knee extensors abruptly falls from its maximum, allowing the necessary fast recoil of the tensed tendon structures to occur.     

Social organization of Galagos in Kenyan coastal forests: II. Galago garnettii

The social organization of Galago garnettii was studied for the first time and the study included data from two different sites in the coastal forests of Kenya. A combination of mark-recapture and radio-tracking techniques was used to investigate patterns of inter- and intrasexual home range overlap. Patterns of range use were established by radio tracking focal individuals. Adult females of different ages shared highly overlapping ranges, while like-aged females showed little range overlap. Females matured and had their first infants in their natal ranges. Adult males' ranges were larger than those of females and overlapped them extensively. Resident adult males showed little range overlap with each other, unless they were of different ages. Turnover of males was frequent in both populations. Males probably dispersed from their natal ranges. Adults rarely slept together. The social organization of G. garnettii is relatively similar to that of the closely related G. crassicaudatus of southern Africa but contrasts with that of its sympatric congener, G. zanzibaricus. The differences and similarities between these three species are discussed in relation to diet and body size.     

Comparative studies of social behavior in Callicebus and Saimiri: Behavioral and physiological responses of established pairs to unfamiliar pairs

The influences of cage size and novelty on the behavior of Galago senegalensis braccatus were examined in two captive groups (five adults and one immature per group) having similarly furnished but unequally sized cages. One group experienced expansion, and the other experienced contraction of space. Each group experienced the novelty of a new cage and return to its old cage. Exploration, nonsocial activity, and social sniffing behaviors were most frequent in both groups during the novelty phase independent of cage size. These behaviors remained elevated after return to the original cage. This pattern indicated that novelty, not space, was responsible for these behavioral changes. The increase in social sniffing indicated that group members may use olfactory cues to recognize each other, expecially when the setting is novel. In both groups, frequencies of displacements and chases were highest in the smaller space. Group differences in behavior prior to cage change also influenced a group's response to change.     

Skin darkness is related to cortisol, but not MSH, content in post‐larval Solea senegalensis

In this study it was shown that dark coloured post‐larvae of Senegalese sole Solea senegalensis , at two different ages, had elevated cortisol concentrations compared with lighter coloured individuals. As melanophore‐stimulating hormone levels were not elevated in dark coloured fish, it is possible that this hormone may not be the main melanotropic hormone involved in stress‐related skin darkening.     

Diapause duration, survival in relation to desiccation and egg-pod morphology of the Senegalese grasshopper, Oedaleus senegalensis

Abstract. The Senegalese grasshopper, Oedaleus senegalensis (Krauss) (Orthoptera: Acrididae), is periodically a devastating pest of subsistence crops in the sahelian zone of West Africa.Egg diapause has been suggested as an important component of the mechanism acting to generate outbreaks and therefore diapause duration, egg survival in relation to desiccation and egg-pod morphology were investigated in this study.
Three months after oviposition, 50% of initially diapausing egg pods maintained in the laboratory exhibited 'partial emergence' and produced hoppers.No difference in diapause duration was evident between egg pods maintained at a constant 30 ± 1°C and those maintained under alternating temperature conditions of 23 ± 1°C and 35 ± 1°C.Laboratory maintained eggs showed significant variation in diapause duration with diapause lasting between 2 months and 4 years.Diapause duration was shorter in the field with only c. 1.4% of eggs remaining in diapause after a single dry season (6–7 months).Survival of eggs in relation to desiccation was high in the field and low in the laboratory, and field eggs lost only c. 20% of their body weight over the dry season.Survival of diapausing and non-diapausing egg pods in the laboratory was similar, indicating that diapause in this species is primarily a mechanism for preventing emergence at an inappropriate time of year, rather than conferring any additional resistance to desiccation.Egg pods oviposited under diapause-inducing conditions (LD 14:10 h, 25°C) were significantly shorter than those laid under non-diapausing conditions (LD 10:14 h, 40°C).These results are discussed both in relation to possible O.senegalensis 'bet-hedging' strategies and to the probable mechanism operating behind major outbreaks of this species.     

Substantial loss of genetic variation in a single generation of Senegalese sole (Solea senegalensis) culture: implications in the domestication process

The flatfish Solea senegalensis represents an important resource in modern mariculture and is largely raised in South Spain and Portugal. Substantial progress has been achieved in its domestication, though suitable reproduction and zootechnical conditions still remain unknown. Difficulties to obtain breeders from wild lead many companies to set up broodstocks with first generation (G1) progeny without genetic guidelines. To study the genetic processes underlying the early stage of domestication of this species, the genetic structure of four representative broodstocks from Southern Spain has been assessed by means of eight microsatellite loci . Data revealed a substantial reduction in levels of genetic variability on just one generation in stocks totally or partially composed of G1 individuals when compared with those solely integrated by individuals from wild. The genetic relatedness within the four stocks has been established, having detected close relationships between individuals from cultured origin, thus suggesting that the loss of variability is apparently due to setting up broodstocks by blind selecting of family related G1 individuals. The high proportion of siblings in these stocks can have negative consequences in future generations due to inbreeding effects. The relationships between the four broodstocks were traced, having found a common origin between two of them, which come from the same donor hatchery, thus enhancing the homogenization of the existent resources for S. senegalensis among the various stocks. This finding alerts about the risks in exchanging fish between hatcheries without knowing their genetic origin. From this study, the use of microsatellites is strongly recommended to control the genetic composition of S. senegalensis broodstocks, aimed to maintain standards of genetic health and improve their reproduction capacity, which is a key issue in the domestication process.     

Growth variability of juvenile soles Solea solea and Solea senegalensis, and comparison with RNA : DNA ratios in the Tagus estuary, Portugal

Growth variability and condition of juvenile soles Solea solea and Solea senegalensis , were assessed through RNA : DNA estimates and compared to absolute growth rates. Higher mean cohort RNA : DNA ratios were observed for cohort I at the beginning of estuarine occurrence for both species (4·42 and 4·87, for S. solea and S. senegalensis respectively). Despite different estuarine colonization habits, no significant differences were observed between RNA : DNA monthly variation for both sole species within the same year ( P  > 0·05 for 2003 and 2004). Juvenile S. senegalensis showed significant differences between RNA : DNA ratios obtained for the two nursery areas ( P  < 0·001). The decrease of seasonal growth rates with fish age was similar to seasonal variation of mean RNA : DNA values. Thus the RNA : DNA pattern of juvenile S. solea and S. senegalensis reflected growth and estuarine colonization patterns.     

Metabolic activity interferometer: description and calibration of an interferometric method to measure growth of mycobacteria

An interferometer that measures the refractive index changes due to bacterial metabolism is described. The apparatus permits simultaneous and real time measurement of bacterial growth in several samples of slowly growing mycobacteria. The error sources are discussed and the sensitivity of the apparatus is tested. For the species Mycobacterium bovis BCG and M. smegmatis, a relation between refractive index change and bacterial concentration is determined experimentally and the time constant of bacterial growth is measured.

Long bone diaphyseal shape follows different ontogenetic trajectories in captive and wild gorillas

Objectives

A number of studies have demonstrated the ontogenetic plasticity of long bone diaphyseal structure in response to mechanical loading. Captivity should affect mechanical loading of the limbs, but whether captive apes grow differently than wild apes has been debated. Here, we compare captive and wild juvenile and adult Gorilla to ascertain whether growth trajectories in cross‐sectional diaphyseal shape are similar in the two environments.

Materials and methods

A sample of young juvenile (n = 4) and adult (n = 10) captive Gorilla gorilla gorilla specimens, with known life histories, were compared with age‐matched wild G.g. gorilla (n = 62) and G. beringei beringei (n = 75) in relative anteroposterior to mediolateral bending strength of the femur, tibia, and humerus. Cross sections were obtained using peripheral quantitative CT.

Results

Captive and wild adult G.g. gorilla differed in bending strength ratios for all three bones, but these differences were not present in young juvenile G.g. gorilla. In comparisons across taxa, captive juvenile G.g. gorilla were more similar to wild G.g. gorilla than to G.b. beringei, while captive adult G.g. gorilla were more similar in shape to G.b. beringei in the hind limb.

Discussion

Captive and wild G. gorilla follow different ontogenetic trajectories in long bone diaphyseal shape, corresponding to environmental differences and subsequent modified locomotor behaviors. Differences related to phylogeny are most evident early in development.