Comparative Stress Response of Black and Gold Howler Monkey (Alouatta caraya) in Urban and Rural Environments of Northern Argentina.

The expansion of human populations associated with urbanization results in extensive modification of natural habitats. While many species cannot persist in these highly modified environments, some species adopt new strategies, which contribute to their survival. Several primate species have persisted in altered habitats, including members of the genus Alouatta. To improve our understanding of this interplay, we compared glucocorticoid (GCC) levels in male and female black and gold howler monkeys (Alouatta caraya) in urban and rural areas in northeastern Argentina. Fecal samples (n = 60) were collected from adults and hormone extracts were analyzed by enzyme immunoassays (EIA). Monkeys living in urban areas (females: 109.15 ± 18.83; males: 106.15 ± 10.48) had lower GCClevels than monkeys living in rural areas (females: 152.01 ± 19.50; males:139,82 ± 10.85). Interestingly, males living in urban areas had lower GCC levels compared to those living in rural areas, whereas no differences were observed in GCC levels between females living in urban and rural areas. While these results suggest that urban areas may provide a release from intergroup competition for male howler monkeys, future work is needed to better understand the dynamics of this association to best inform management and conservation of this vulnerable species.

Non-invasive endocrine monitoring of ovarian and adrenal activity in chinchilla (Chinchilla lanigera) females during pregnancy, parturition and early post-partum period.

The chinchilla is a rodent that bears one of the finest and most valuable pelts in the world. The wild counterpart is, however, almost extinct because of a drastic past and ongoing population decline. The present work was developed to increase our knowledge of the reproductive physiology of pregnancy and post-partum estrus in the chinchilla, characterizing the endocrine patterns of urinary progesterone, estradiol, LH and cortisol metabolites throughout gestation and post-partum estrus and estimating the ovulation timing at post-partum estrus. Longitudinal urine samples were collected once per week throughout pregnancy and analyzed for creatinine, cortisol, LH, estrogen and progesterone metabolite concentrations. To indirectly determine the ovulation timing at post-partum estrus, a second experiment was performed using pregnant females subjected to a post-partum in vivo fertilization scheme. Urinary progestagen metabolites increased above baseline levels in early pregnancy between weeks-8 and -11 respectively to parturition, and slightly declined at parturition time. Urinary estrogens showed rising levels throughout mid- and late pregnancy (weeks-9 to -6 and a further increase at week-5 to parturition) and decreased in a stepwise manner after parturition, returning to baseline levels two weeks thereafter. Cortisol metabolite levels were relatively constant throughout pregnancy with a tendency for higher levels in the last third of gestation and after the pups' birth. Parturition was associated with dramatic reductions in urinary concentrations of sex steroids (especially progestagens). Observations in breeding farms indicated that the females that resulted in a second pregnancy after mating, did so on the second day after parturition. These data were in agreement with an LH peak detected 24h after parturition. Urinary steroid hormone patterns of estrogen and progestagen metabolites provided valuable information on endocrine events during pregnancy and after parturition in the chinchilla. Results presented in this study enhance our understanding of natural reproductive dynamics in the chinchilla and support empirical observations of breeders that post-partum ovulation occurs ∼ 48 h after parturition.

Adrenal activity and anxiety-like behavior in fur-chewing chinchillas (Chinchilla lanigera).

Due to its complexity, in combination with a lack of scientific reports, fur-chewing became one of the most challenging behavioral problems common to captive chinchillas. In the last years, the hypothesis that fur-chewing is an abnormal repetitive behavior and that stress plays a role in its development and performance has arisen. Here, we investigated whether a relationship existed between the expression and intensity of fur-chewing behavior, elevated urinary cortisol excretion and anxiety-related behaviors. Specifically, we evaluated the following parameters in behaviorally normal and fur-chewing animals of both sexes: (1) mean concentrations of urinary cortisol metabolites and (2) anxiety-like behavior in an elevated plus-maze test. Urinary cortisol metabolites were higher only in females that expressed the most severe form of the fur-chewing behavior (P≤0.05). Likewise, only fur-chewing females exhibited increased (P≤0.05) anxiety-like behaviors associated with the elevated plus-maze test. Overall, these data provided additional evidence to support the concept that fur-chewing is a manifestation of physiological stress in chinchilla, and that a female sex bias exists in the development of this abnormal behavior.

Effects of dietary omega-3 PUFAs on growth and development: Somatic, neurobiological and reproductive functions in a murine model.

Omega-3 polyunsaturated fatty acids (ω-3 PUFAs) are relevant to fetal and infant growth and development. Objective: to assess whether long-term exposure to dietary ω-3 PUFA imbalance alters pre- and/or postnatal pups' development and reproductive function later in life. Mice dams were fed with ω-3 PUFA Control (soybean oil, 7%), Deficient (sunflower oil, 7%) or Excess (blend oil; 4.2% cod-liver+2.8% soybean) diet before conception and throughout gestation-lactation and later on, their pups received the same diet from weaning to adulthood. Offspring somatic, neurobiological and reproductive parameters were evaluated. Excess pups were lighter during the preweaning period and shorter in length from postnatal day (PND) 7 to 49, compared to Control pups (P<.05). On PND14, the percentage of pups with eye opening in Excess group was lower than those from Control and Deficient groups (P<.05). In Excess female offspring, puberty onset (vaginal opening and first estrus) occurred significantly later and the percentage of parthenogenetic oocytes on PND63 was higher than Control and Deficient ones (P<.05). Deficient pups were shorter in length (males: on PND14, 21, 35 and 49; females: on PND14, 21 and 42) compared with Control pups (P<.05). Deficient offspring exhibited higher percentage of bending spermatozoa compared to Control and Excess offspring (P<.05). These results show that either an excessively high or insufficient ω-3 PUFA consumption prior to conception until adulthood seems inadvisable because of the potential risks of short-term adverse effects on growth and development of the progeny or long-lasting effects on their reproductive maturation and function.

Expression of FcRn receptor in placental tissue and its relationship with IgG levels in term and preterm newborns.

PROBLEM: IgG is the only antibody class, that is, actively transferred from the mother to the fetus across the placenta by an active, neonatal Fc receptor (FcRn) mediated process during pregnancy, conferring passive immunity and protection against infections to the newborn during the first months of life. Preterm infants may not receive sufficient titers of protective antibodies, as most of them are transferred only after the 34th week of gestation. Because of the great importance of this process, we investigated in a clinical setting the placental transmission of IgG antibodies in term and preterm newborns. METHOD OF STUDY: This work was conducted in 85 woman and their newborns, divided into four groups according to their clinical gestational age (≤37 weeks were considered as preterm). Blood samples were collected from the mothers and their newborns' umbilical cords to analyze total serum IgG concentrations, and a subgroup of 32 placentas was analyzed by immunohistochemistry to quantify the expression of the FcRn receptor. RESULTS: Total IgG levels in both mothers and neonates increased significantly through the third trimester of gestation. Regarding the newborns, in all groups, IgG levels exceeded their mother's values by a ~2.4%. A higher expression of FcRn was detected in placentas from newborns at week 36 of gestation onwards. CONCLUSION: Our results obtained from clinical samples, were in line with previous descriptions in model systems and confirmed that the IgG transfer from maternal serum to the fetus is positively correlated with FcRn expression in placental tissue throughout gestation.

Time-related changes in functional activity and capacitation of chinchilla (Chinchilla lanigera) spermatozoa during in vitro incubation.

The application of assisted breeding programs for chinchilla, an endangered species, requires detailed knowledge about their gamete physiology. Main purposes of the present study were to examine the time-related changes during 8h in vitro incubation in parameters that reflect chinchilla sperm functional activity (including sperm motility, viability, membrane and acrosome integrity), and to determine the incubation time required for achieving in vitro sperm capacitation, evaluated through the quantification of the percentages of sperm that underwent the acrosome reaction in response to progesterone (P, 20 microM) or another acrosome reaction inducer the calcium ionophore, A23187 (20 nM). Semen was obtained by electroejaculation, subjected to swim-up and incubated for 0, 2, 4 and 8h. After these periods, sperm functional activity was assessed. In all treatments percentages of motile, viable and viable sperm with intact acrosomes decreased (p<0.001) after 8h of incubation. The percentages of swollen gametes decreased (p<0.001) after 2h of incubation. Capacitation of chinchilla sperm could be achieved within 4h, as indirectly demonstrated by the increase of acrosome reacted cells in response to P or A23187 (time x treatment interaction: p=0.02).

[Analysis of nasal cytology in children and adolescents with rhinitis]. / Análisis de la citología nasal en niños y adolescentes con rinitis.

BACKGROUND: Nasal cytology in a easy-to apply method to differentiate rhinitis phenotypes from a physiopathogenic and diagnostic perspective. There are controversies about the relationship between clinical severity of rhinitis and inflammatory patterns expressed in the nasal cytology. OBJECTIVES: To study the characteristic of the eosinophil and neutrophil patterns in the nasal scraping for Allergic Rhinitis (AR) and Non Allergic Rhinitis (NAR) and its relationship with the clinical grades of rhinitis established by the Allergic Rhinitis and its Impact on Asthama Guideline (ARIA) Methods: In a observational, cross-sectional study we included patients aged 5 to 18 years presenting symptoms of either allergic (AR) or non- allergic rinitis (NAR) without asthma. Cytology was performed by analyzing nasal scraping obtained from the mucosal surface of the inferior turbinate and samples were stained using thr hematoxylin and eosin stain procedure. Inflammatory patterns between AR and NAR and between clinical grades of rhinitis classified by ARIA guide were compared. RESULTS: A total of 231 patients were included. Patients with AR exhibited higher percentage of eosinophils in nasal cytology than those with NAR (p = 0.0012) but no differences were observed in neutrophil count (p = 0.4011). No differences in the percentage of eosinophils and neutrophils between different grades of AR (p = 0.7342 and p = 0.0797 respectively) and NAR (p = 0.1010 and p = 0.1422 respectively) were observed. CONCLUSION: Eosinophil count in the nasal cytology was useful to differentiate rhinitis with a positive allergen skin test from rhinitis with negative skin test, but as neutrophils count, does not help to distinguish clinical grades of AR and NAR as classified by ARIA.

Reproductive performance and weaning success in fur-chewing chinchillas (Chinchilla lanigera).

In captive chinchillas, one of the most challenging behavioral problems is the development of a stress-related abnormal repetitive behavior (ARB) known as "fur-chewing". We investigated whether there is a relationship between the severity of fur-chewing behavior and reproductive function in male and female chinchillas. Regardless of the severity of abnormal behavior, fur-chewing males did not show significant differences in seminal quality (sperm concentration, motility and viability; integrity of sperm membrane and acrosome) and the response to the process of semen collection (the number of stimuli needed to achieve ejaculation) when compared to those with normal behavior. Also, females showing normal or fur-chewing behavior presented similar reproductive performance in terms of number of litters per female per year and litter size. However, pup survival rate was lower (p=0.05) in fur-chewing females than in normal females. These results seem to be consistent with data suggesting non-significant effects of ARBs on reproductive performance.

Estructura de la placenta y su impacto en la transferencia de la inmunidad materno-fetal: revisión en mamíferos domésticos / Structure of the placenta and its impact on the transfer of maternal-fetal immunity: a review in domestic mammals

La placenta es un órgano imprescindible para llevar adelante la gestación en mamíferos domésticos. Está constituida por tejidos maternos y fetales y cumple numerosas funciones: intercambio de gases, nutrientes y excreción de productos de desecho, función inmune a nivel de tolerancia y transferencia, función endócrina sintetizando hormonas y factores de crecimiento. Existe una gran diversidad estructural en las placentas de diferentes especies animales. Las clasificaciones de mayor relevancia son la que dependen de la descripción morfológica macroscópica, basada en la distribución de las vellosidades placentarias en el corion del feto y la clasificación histológica, fundamentada en el número de capas que se interponen entre la sangre materna y la fetal, determinando la transferencia de inmunoglobulinas (Igs) a través de este órgano. El objetivo del presente trabajo es describir la estructura placentaria en diferentes especies y su impacto en la transferencia de la inmunidad materno-fetal. (AU)

The placenta is an essential organ for pregnancy in domestic mammals. It is constituted by maternal fetal tissues and fulfills numerous functions: exchange of gases, nutrients and excretion of waste products, prevents the immune system from identifying the embryo as a foreign body and synthesizes hormones and growth factors. There is great structural diversity in placentas of different animal species, and those can be classified in different ways. The most relevant is the macroscopic morphological classification, which is based on the distribution of the placental villi in the corium of the fetus, and the histological, that relies on the number of layers between maternal and fetal blood, determining if there is immunoglobulin (Ig) transfer or it is carried out through the colostrum. The objective of the work is to describe the placental structure in different species and its impact on the transfer of maternal-fetal immunity. (AU)

Differential effects of fluoxetine and venlafaxine on memory recognition: possible mechanisms of action.

Serotonin-specific reuptake inhibitors (SSRI) and serotonin-norepinephrine reuptake inhibitors (SNRI) are antidepressant drugs commonly used to treat a wide spectrum of mood disorders (Wong and Licinio, 2001). Although they have been clinically used for more than 50 years, the molecular and cellular basis for the action of SSRIs and SNRIs is not clear. Considering that the changes in gene expression involved in the action of antidepressant drugs on memory have not been identified, in this study we investigated the impact of chronic treatment with a SSRI (fluoxetine) and a SNRI (venlafaxine) on the mRNA expression of genes related to memory cascade in the mouse hippocampus, namely, α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA), nitric oxide synthase 1 (NOS1), neurotrophic tyrosine kinase receptor type 2 (TrKB), mitogen-activated protein kinases (MAPK/ERK) and serotonin transporter (SERT). Animals treated with fluoxetine 10 mg/Kg/day for 28 days showed a significant decrease in the percentage of time spent in the novel object recognition test (p≤0.005) and induced MAPK1/ERK2 down-regulation (p=0.005). Our results suggest that the effect on cognition could probably be explained by fluoxetine interference in the MAPK/ERK memory pathway. In contrast, chronic treatment with venlafaxine did not reduce MAPK1/ERK2 expression, suggesting that MAPK1/ERK2 down-regulation is not a common effect of all antidepressant drugs. Further studies are needed to examine the effect of chronic fluoxetine treatment on the ERK-CREB system, and to determine whether there is a causal relationship between the disruption of the ERK-CREB system and the effect of this antidepressant on memory performance.

Acute ghrelin administration reverses depressive-like behavior induced by bilateral olfactory bulbectomy in mice.

This study aims to examine the antidepressant-like action of Ghrelin (Ghr), a hormone synthesized predominantly by gastrointestinal endocrine cells and released during periods of negative energy balance, in two behavioral models: tail suspension test (TST), a predictive model of antidepressant activity, and the olfactory bulbectomy (OB), an established animal model of depression. The reduction in the immobility time in the TST was the parameter used to assess antidepressant-like effect of Ghr. The depressive-like behavior in olfactory bulbectomized mice was inferred through the increase in the immobility time in the TST and the hyperlocomotor activity in the open-field test. Ghr produced antidepressant-like effect in TST (0.3 nmol/µl, i.c.v.), and reversed OB-induced depressive-like behavior. In conclusion, these results provide clear evidence that an acute administration of ghrelin produce antidepressant-like effect in the TST and OB.

A non-invasive method for assessing adrenal activity in the chinchilla (Chinchilla lanigera).

The Chinchilla is a rodent that was once abundant in the central Andes of South America. Excessive hunting for fur greatly reduced its distribution at the beginning of the twentieth century, and today Chinchilla species are nearly extinct in the wild. Although protected, wild populations of chinchilla are still declining. In general, this species has received little research attention and its biology is poorly understood. Improvements in captive breeding, husbandry, and genetic management are needed to ensure the conservation of the species. In this study, a noninvasive corticosteroid hormone monitoring technique was validated for use in Chinchilla lanigera. Two male domestic chinchillas were administered 3H-corticosterone (i.m.) to determine the time course and relative proportion of urinary and fecal steroid metabolites. Most radioactivity was detected in urine and feces 5-10 and approximately 30 h post-isotope administration, respectively. Corticosteroid immunoreactivity was assessed by corticosterone radioimmunoassay (RIA) and cortisol enzyme immunoassay (EIA). High-pressure liquid chromatography (HPLC) separation of corticosteroid metabolites in unprocessed urine revealed the presence of highly polar corticosteroid metabolites, but after enzymatic hydrolysis and diethyl ether extraction, most immunoreactivity co-eluted with unconjugated cortisol. A 'cause-and-effect' relationship between the administration of exogenous adrenocorticotrophic hormone (ACTH), and the appearance of increased urinary corticosteroid metabolites demonstrated the physiological relevance of these measures for evaluating adrenal status in male chinchillas. From a conservation perspective, these methods can aid in situ and ex situ initiatives designed to evaluate how environmental conditions and management strategies affect overall animal health, well-being and reproduction.