Ecology and age, but not genetic ancestry, predict fetal loss in a wild baboon hybrid zone.

OBJECTIVES: Pregnancy failure represents a major fitness cost for any mammal, particularly those with slow life histories such as primates. Here, we quantified the risk of fetal loss in wild hybrid baboons, including genetic, ecological, and demographic sources of variance. We were particularly interested in testing the hypothesis that hybridization increases fetal loss rates. Such an effect would help explain how baboons may maintain genetic and phenotypic integrity despite interspecific gene flow. MATERIALS AND METHODS: We analyzed outcomes for 1020 pregnancies observed over 46 years in a natural yellow baboon-anubis baboon hybrid zone. Fetal losses and live births were scored based on records of female reproductive state and the appearance of live neonates. We modeled the probability of fetal loss as a function of a female's genetic ancestry (the proportion of her genome estimated to be descended from anubis [vs. yellow] ancestors), age, number of previous fetal losses, dominance rank, group size, climate, and habitat quality using binomial mixed effects models. RESULTS: Female genetic ancestry did not predict fetal loss. Instead, the risk of fetal loss is elevated for very young and very old females. Fetal loss is most robustly predicted by ecological factors, including poor habitat quality prior to a home range shift and extreme heat during pregnancy. DISCUSSION: Our results suggest that gene flow between yellow and anubis baboons is not impeded by an increased risk of fetal loss for hybrid females. Instead, ecological conditions and female age are key determinants of this component of female reproductive success.

Effects of Moringa oleifera aqueous seed extracts on reproductive traits of heat-stressed New Zealand white female rabbits.

Heat stress is reported to have deleterious effects on rabbit physiology by impairing reproductive performances arising from free radical production due to oxidative stress. Plant extracts have been listed among efficient and healthy strategies for alleviating the effects of free radicals in the body of an animal. Numerous studies have documented the medicinal value of Moringa oleifera on various body functional systems although most of these data have not been scientifically validated. The growing concern of heat stress owing to the effects of global warming has affected animal productivity and even reproductive health, yet mitigation measures are still scanty. To this end, we investigated the efficacy of Moringa oleifera aqueous seed extract on selected in the alleviation of morphofunctional impairments on functional systems of the body. Here, we quantified the effects of Moringa oleifera seed extracts on reproductive performances, hormonal profile, and ovarian histology in the management of heat stress in female rabbits. We were particularly interested in testing the hypothesis that Moringa oleifera seed extracts do not have medicinal value in the mitigation of oxidative stress accompanying heat-stressed animals and, therefore, affecting growth performance and reproductive value. Twenty-eight female rabbits aged 6 months and weighing between 2015.6 and 2322.7 g were randomly assigned to four treatment groups of temperature, relative humidity, temperature humidity index, and M. oleifera seed extracts as follows: T0: ambient temperature (18-24°C), 59 ± 0.48%, 23.6 ± 1.52; T1, T2, and T3: 35-36°C, 64 ± 0.6%, 32.5 ± 0.7, followed by 100, 200, and 0 mg/kg b.w of M. oleifera seed extracts. Artificial heat was introduced in each rabbit cage from 08:00 h to 16:00 h. Reproductive performances related to female rabbits and relevant biodata of their young ones were recorded. All animals were sacrificed at the end of 80 days of experiments, and blood was collected for hormonal assays and ovary tissues for histology. Data on hormones and reproductive parameters of adult females as well as parameters related to kid performance and milk yield were subjected to one-way ANOVA, and significant differences among treatment subjects were analyzed using Tukey's post-hoc test at 5% significance level. The results revealed a significant decrease (P < 0.05) in food consumption, body weight, and body weight gain in pregnant and lactating female rabbits exposed to heat stress. A decrease in fur removal by mothers, litter size from birth to weaning, litter weight, kid body weight, and body weight gain in adult rabbits submitted to heat stress was observed. The findings were also reflected on weekly milk yield and daily milk efficiency as well as serum hormone levels. Following administration of M. oleifera seed extracts at 200 mg/kg b.w., there was significant increase (P < 0.05) in these parameters. On the contrary, an increase (P < 0.05) in the number of services per conception, milk intake, and serum progesterone level was initially observed in the same subjects, but upon administration of M. oleifera seed extracts, there was a significant decrease (P < 0.05) on these measures. Ovarian histology of animals at T0 and T2 treatments showed structural features comparable to those of controls. Overall, our results show that administration of M. oleifera seed extracts at 200 mg/kg b.w possesses therapeutic value to the effects of oxidative stress associated with heat stress. Further pharmacological evaluation on seed extracts of M. oleifera may yield the much-needed medicine in the treatment and management of poor animal productivity and reproductive health arising from severe weather associated with global warming.

Acute and sub-chronic effects of purified cathinone from khat (Catha edulis) on behavioural profiles in vervet monkeys (Chlorocebus aethiops).

We investigated the cumulative effects of cathinone on behavioural alterations in single-caged vervet monkeys. Fourteen adult vervets were divided into tests (12 animals) and controls (2 animals), and exposed to escalating doses of cathinone at alternate days of each week for 4 months in presence and absence of cage enrichment. One month of pre-treatment phase served to establish baseline values. Composite behavioural scores of aggression, anxiety, abnormal responses, withdrawal and appetite loss were done. A series of repeated measures analysis of variances were conducted to examine the extent to which cathinone administration was associated with patterns of changes in behavioural data. Results indicate a dose-dependent effect of cathinone on increases of aggression, anxiety, abnormal responses, withdrawal, and appetite loss. The findings demonstrate that at high doses and long-term exposure, cathinone causes behavioural alterations probably via changes in presynaptic striatal dopamine system.

Dose-response inhibitory effects of purified cathinone from khat (Catha edulis) on cortisol and prolactin release in vervet monkeys (Chlorocebus aethiops).

This study reports acute and sub-chronic effects of cathinone on hormonal alterations in single-caged vervet monkeys. Fourteen adult vervet monkeys were used, 12 of which were treated and 2 controls. Pre-treatment phase of 1 month aimed at establishing baseline levels of hormones while treatment phase of 4 months considered the dose- and time-response effects of cathinone on serum cortisol and prolactin levels. Test animals were allocated four groups of three animals each and administered 0.8, 1.6, 3.2 and 6.4 mg/kg body weight of cathinone orally while controls were administered normal saline. Treatment was done at alternate days of each week. Serum prolactin and cortisol immunoassays were done. Hormonal data was analysed by repeated measures ANCOVA. Results indicate a dose [F (4, 8) = 218, P < 0.001] and time [F (18, 142) = 21.7, P < 0.001] dependent effect of cathinone on cortisol levels with a significant dose by week interaction [F (71, 142) = 4.86, P < 0.001]. Similarly, there was a decrease in serum prolactin [F (4, 8) = 267, P < 0.001] with escalating doses of cathinone with a significant dose x week interaction [F (59, 118) = 13.03, P < 0.001]. The findings demonstrate that at high doses and long-term exposure, cathinone causes hormonal alterations probably via changes in hypothalamo-hypophyseo-adrenocortical and gonadal axes integrity.

In vitro study of the effects of khat (Catha edulis Forsk) extract on isolated mouse interstitial cells.

Isolated mouse interstitial cells were incubated with different concentrations of khat (Catha edulis) extract (0.06 mg/ml, 0.6 mg/ml, 6 mg/ml, 30 mg/ml and 60 mg/ml) and cell viability as well as testosterone concentration measured at 30 min intervals over a 3h incubation period. High concentrations of khat extract (30 mg/ml and 60 mg/ml) significantly inhibited testosterone production while low concentrations (0.06 mg/ml, 0.6 mg/ml and 6 mg/ml) significantly stimulated (P<0.05) testosterone production by mouse interstitial cells. Similarly, at concentrations of 30 mg/ml and 60 mg/ml, there was a significant decrease in interstitial cell viability, whereas at 0.06 mg/ml, 0.6 mg/ml and 6 mg/ml there was no significant decrease. There was only a weak correlation (r=0.39) between testosterone production and viable interstitial cells. We postulate that khat extract at high concentrations may cause reproductive function impairment in the user but at low concentrations, may enhance testosterone production with accompanying effects on reproductive functions in male mice.