Pulmonary Maturation in Canine Foetuses From Early Pregnancy to Parturition

Development of the foetal respiratory system includes both pulmonary growth and maturation. In human medicine, a higher incidence of respiratory distress is reported in newborn males. This study aimed to identify different phases of canine foetal lung maturation throughout pregnancy, to determine the stage of pregnancy in which surfactant production begins and to compare pulmonary development of male and female foetuses. Pregnant bitches (34) were subjected to elective ovariohysterectomy and allocated into four groups, according to the stage of pregnancy: 30-40 days of pregnancy (n = 10), 41-50 days (n = 10), 51-60 days (n = 10) and bitches in the first stage of parturition (n = 4). Foetal lungs were histologically processed and evaluated by optical microscopy. The pseudoglandular phase was identified between the 35th day and 46th day of gestation; the onset of canalicular and saccular periods was observed, respectively, from the 48th day and 60th day of pregnancy. Lungs from foetuses at term were in the saccular phase; thus, the development into the alveolar period occurs in the neonatal period. The histological analyses revealed that respiratory tract development is centrifugal, from upper to lower airways. Therefore, it is possible to identify distinct development periods in different portions of the same organ. In conclusion, the saccular phase of lung development begins around 57 and 60 days of pregnancy, the period in which surfactant production is believed to occur. Male and female foetuses present similar pulmonary development from early pregnancy until parturition.

Neonatal Clinical Evaluation, Blood Gas and Radiographic Assessment After Normal Birth, Vaginal Dystocia or Caesarean Section in Dogs

This study aimed to standardize signs and diagnostic criteria of respiratory function in newborn puppies delivered normally or after dystocia and caesarean operation. A total of 48 neonates were allocated into groups: eutocia (n = 20), dystocia (n = 8), caesarean (c)-section (n = 20). Neonatal health was assessed using the Apgar score and body temperature was determined at 0, 5 and 60 min after delivery. Venous blood gases (pO(2) and SO(2)) was measured immediately and 60 min after delivery, and a thoracic radiograph was made between 0 and 5 min of life. The c-section group had significantly lower Apgar scores at birth and 5 min. Hypothermia was present at 5 min in the eutocia and c-section groups, and at 60 min in all groups. The eutocia group had an irregular respiratory pattern in 78% of puppies at birth, 27.7% at 5 min and 21% at 60 min compared with 87.5%, 62.5% and 12.5% of the pups in the dystocia group where there was irregular respiratory rhythm, moderate to intense respiratory sounds with agonic episodes. The c-section group had respiratory alterations in 70%, 45% and 16% of puppies at 0, 5 and 60 min, respectively. Radiographic abnormalities were present in 17% of the pups in the eutocia group, 25% of the pups in the dystocia group and 30% of the pups in the c-section group, respectively. The c-section group had significantly lower SO(2) values at 60 min than at birth. All puppies had hypoxaemia, but a significant decrease was observed in the c-section group. Newborn puppies had tissue hypoxia and irregular respiratory pattern at birth. Caesarean-section puppies had lower vitality; however, all developed satisfactory Apgar scores at 5 min of life, regardless of the obstetric condition.

Acid-Base Changes in Canine Neonates Following Normal Birth or Dystocia

There are limited data concerning blood gas parameters in neonatal dogs. Knowledge of the normal physiology may facilitate effective therapeutic intervention and potentially reduce neonatal mortality. This study examined acid-base parameters in pups born at normal parturition (n = 27) compared with those born after obstetrical assistance or caesarean operation (n = 13) and those born following oxytocin (OXY) administration for treatment of uterine inertia (n = 11). Pups were subjected to an objective scoring method of neonatal health adapted from use in humans (the Apgar score) at birth and again at 5 and 60 min after birth. Venous blood samples were collected at 5 and 60 min after birth for evaluation of blood gas parameters. At birth, all pups had low Apgar scores and a mixed acidosis. The base excess was lowest for pups delivered after OXY administration. The Apgar score improved for all pups after 5 min of birth and there was an improvement in carbon dioxide tension, base excess and venous blood pH at 1 h, although in all pups a metabolic acidosis persisted. These data provide an important insight into neonatal physiology and the variability of blood gas parameters in pups born at normal and abnormal parturition and provide the basis for clinical decision making following dystocia.

Evaluation of Trypsin Treatment on the Inactivation of Bovine Herpesvirus Type 1 on In Vitro Produced Pre-implantation Embryos

The aim of this study was to evaluate the efficiency of trypsin treatment on the inactivation of bovine herpesvirus type 1 (BoHV-1) on in vitro produced by fertilization and artificially infected bovine embryos. Bovine embryos on day 7 were exposed with 10 mu l of BoHV-1, Los Angeles strain 10(7.5) TCID. These embryos and control embryos were divided in two groups: submitted to the sequential washes or to the trypsin treatment according to the International Embryo Transfer Society (IETS) guidelines. The embryos and the last washing drop of each group were used as inoculum to infect Madin Darby bovine kidney (MDBK) cells and submitted to nested PCR reaction using the primer that encodes the gene conserved region of virus glycoprotein gB. The data have shown that the control embryos and their last washing drop were negative. The exposed embryos that were treated with trypsin have shown positive results on the n-PCR and MDBK culture, and their last washing drop were negative. Our data have demonstrated that the trypsin treatment was not able to eliminate the BHV-1 of the embryos, suggesting an interaction between virus and embryo.

Human immature dental pulp stem cells` contribution to developing mouse embryos: production of human/mouse preterm chimaeras

In this study, we aimed at determining whether human immature dental pulp stem cells (hIDPSC) would be able to contribute to different cell types in mouse blastocysts without damaging them. Also, we analysed whether these blastocysts would progress further into embryogenesis when implanted to the uterus of foster mice, and develop human/mouse chimaera with retention of hIDPSC derivates and their differentiation. hIDPSC and mouse blastocysts were used in this study. Fluorescence staining of hIDPSC and injection into mouse blastocysts, was performed. Histology, immunohistochemistry, fluorescence in situ hybridization and confocal microscopy were carried out. hIDPSC showed biological compatibility with the mouse host environment and could survive, proliferate and contribute to the inner cell mass as well as to the trophoblast cell layer after introduction into early mouse embryos (n = 28), which achieved the hatching stage following 24 and 48 h in culture. When transferred to foster mice (n = 5), these blastocysts with hIDPSC (n = 57) yielded embryos (n = 3) and foetuses (n = 6); demonstrating presence of human cells in various organs, such as brain, liver, intestine and hearts, of the human/mouse chimaeras. We verified whether hIDPSC would also be able to differentiate into specific cell types in the mouse environment. Contribution of hIDPSC in at least two types of tissues (muscles and epithelial), was confirmed. We showed that hIDPSC survived, proliferated and differentiated in mouse developing blastocysts and were capable of producing human/mouse chimaeras.

LH surge in Nelore cows (Bos indicus), after induced estrus or after ovarian superestimulation

Considering, that there is limited information about the preovulatory LH surge in Zebu Cattle (Bos indicus). the purpose of the present work was to assess the LH surge in Nelore cows during the estrous cycle and after ovarian superestimulation of ovarian follicular development with FSH. This information is particularly important to improve superovulatory protocols associated with fixed-time artificial insemination. Nelore cows (n = 12) had their estrus synchronized with all intravaginal device containing progesterone (CIDR-B (R)) associated with estradiol benzoate administration (EB, 2.5 mg, i.m., Day 0). Eight days later all animals were treated with PGF2 alpha (Day 8) in the morning (8:00 h) and at night, when CIDR devices were removed (20:00 11). Starting 38 h after the first PGF2 alpha injection, blood sampling and ovarian ultrasonography took place every 4 h, during 37 consecutive hours. Frequent handling may have resulted in a stress-induced suppression of LH secretion resulting in only 3 of 12 cows having ovulations at 46.7 +/- 4.9 and 72.3 +/- 3.8 h, respectively, after removal of CIDR-B. Thirty days later, the same animals received the described hormonal treatment associated with FSH (Folltropin (R) total dose = 200 mg) administered twice a day, during 4 consecutive days, starting on Day 5. Thirty-six hours after the first injection of PGF2 alpha, to minimize stress. only seven blood samples were collected at 4 h interval each. and ultrasonography was performed every 12 h until ovulation. In 11 of 12 cows (92%) the LH surge and ovulation were observed 34.6 +/- 1.6 and 59.5 +/- 1.9 h. respectively. after removal of progesterone source. The maximum values for LH in those animals were 19.0 +/- 2.6 ng/ml (mean +/- S.E.M.). It is concluded that, in Nelore COWS submitted to a ovarian superstimulation Protocol, the LH surge occurs approximately 35 It after removal of intravaginal device containing progesterone, and approximately 12h before the LH surge observed after an induced estrus without ovarian superstimulation (C) 2008 Elsevier B.V. All rights reserved.

Oviductal Fluid Proteins Associated with the Bovine Zona Pellucida and the Effect on In Vitro Sperm-Egg Binding, Fertilization and Embryo Development

Studies have demonstrated that oviductal fluid (ODF) proteins associate with eggs of numerous species including the bovine. In this study, the association of three ODF proteins, the bovine oestrus-associated protein, osteopontin (OPN), lipocalin-type prostaglandin D synthase (L-PGDS), with the bovine zona pellucida (ZP) was demonstrated by immunohistochemistry and western blot. The biological function of ODF derived egg-associated OPN and L-PGDS in sperm binding, fertilization and embryonic development was also explored. In vitro matured bovine oocytes were pre-incubated with ODF collected by cannula from cows in oestrus, or ODF with antibodies to OPN, L-PGDS and bovine serum albumin (BSA). Following incubation, oocytes were inseminated with 1 x 10(5) frozen-thawed spermatozoa, and they were evaluated for sperm binding, fertilization and embryonic development in vitro. Pre-treatment of ODF with antibodies to all of proteins reduced sperm binding to the ZP and fertilization in vitro. Cleavage rates were not significantly different among incubations, but rates of embryo development were significantly decreased. We conclude that antibodies to OPN, L-PGDS and BSA react with oocytes incubated with ODF and inhibit sperm binding, fertilization and embryonic development in vitro, suggesting a potential role of these proteins in these events.

Effects of sperm concentration and straw volume on motion characteristics and plasma, acrosomal, and mitochondrial membranes of equine cryopreserved spermatozoa

The advantages of using cryopreserved semen in equine reproduction are well known. During cryopreservationl spermatozoa undergo many changes that lead to a decrease in fertility. There is no agreement on the ideal sperm dose and concentration to maximize fertility rates. Thus, the objectives of this experiment were to evaluate sperm motion by computer-assisted analysis (CASA), sperm membrane integrity and function with fluorescence probes of cryopreserved sperm at three concentrations: 100 (C100), 200 (C200) and 400 x 10(6) sperm/mL (C400), and two straw volumes (0.50 and 0.25 mL). There was no interaction between sperm concentration and storage volume (P > .05). Sperm motion characteristics were influenced by concentration (C100 > C200 > C400; P < .05). Curvilinear velocity (VCL) in 0.25-mL straws had higher average values (P < .05). Membrane integrity and function were not changed by straw volume (P > .05). However, sperm concentration changed the percentage of cells with intact plasma membrane (C100 > C200 > C400; P < .05) and the percentage of cells with high mitochondrial membrane potential (C100 = C200; P > .05 and C400 < C100 and C200; P < .05). According to this experiment, the best freeing method was that involving 100 x 10(6) sperm/mL, regardless of straw volume.

Placentation in the Amazonian manatee (Trichechus inunguis)

Evidence from several sources supports a close phylogenetic relationship between elephants and sirenians. To explore whether this was reflected in similar placentation, we examined eight delivered placentae from the Amazonian manatee using light microscopy and immunohistochemistry. In addition, the fetal placental circulation was described by scanning electron microscopy of vessel casts. The manatee placenta was zonary and endotheliochorial, like that of the elephant. The interhaemal barrier comprised maternal endothelium, cytotrophoblasts and fetal endothelium. We found columnar trophoblast beneath the chorionic plate and lining lacunae in this region, but there was no trace in the term placenta of haemophagous activity. The gross anatomy of the cord and fetal membranes was consistent with previous descriptions and included a four-chambered allantoic sac, as also found in the elephant and other afrotherians. Connective tissue septae descended from the chorionic plate and carried blood vessels to the labyrinth, where they gave rise to a dense capillary network. This appeared to drain into shorter vessels near the chorionic plate. The maternal vasculature could not be examined in the same detail, but maternal capillaries ran rather straight and roughly parallel to the fetal ones. Overall, there is a close resemblance in placentation between the manatee and the elephant.

Reproductive development and function of female rats exposed to di-eta-butyl-phthalate (DBP) in utero and during lactation

Phthalates are environmental contaminants used in the production of plastics, cosmetics and medical devices. Studies on the effects of phthalates on female reproductive health are particularly sparse and mostly restricted to high-dose exposure in rats. In the present study, pregnant rats were treated with 100 mg/kg-d of di-eta-butyl-phthalate (DBP) or only the vehicle (control group), from GD 12 to GD 20 for evaluation of reproductive outcomes and fetal gonads analysis (F0), and from GD 12 to PND 21 to evaluate reproductive development and function on F1 female offspring. Results showed that all parameters were comparable between groups, although there was a significant increase in the fetal weight after DBP exposure. However, the body weight at birth was normal. Based on these data we can conclude that, in these experimental conditions, DBP did not disturb the reproductive development or function of female rats. (C) 2009 Elsevier Inc. All rights reserved.

Effect of Sodium Cyclamate on the Rat Fetal Exocrine Pancreas: a Karyometric and Stereological Study

The cyclamate, a sweetner substance derived from N-cyclo-hexyl-sulfamic acid, is largely utilized as a non-caloric artificial edulcorant in foods and beverages as well as in the pharmaceutical industry. The objective of this study was to evaluate karyometric and stereological alterations in the rat fetal pancreas resulting from the intraperitoneal administration of sodium cyclamate. The exocrine pancreas of ten fetuses of rats were evaluated, five treated and five controls chosen at random, in which five rats that received from the 10th to 14th days of pregnancy an intraperitoneal daily injection of sodium cyclamate at 60 mg/Kg of body weight during 5 days. At the 20th day of gestation, the animals were removed and weighed, as were their placentas; the length of the umbilical cords also were measured. After the laboratory processing, semi-seriated 6mm cuts stained with haematoxyline and cosine were performed. In seven karyometric parameters (major, minor, and medium diameters, volume, area, perimeter, and volume-area ratio), the increase was statistically significant in the treated group when compared with control group. Stereological parameters showed in the treated group a significant increase in the cellular volume and a significant reduction in the numerical cellular density. These results showed that the sodium cyclamate in pregnant rats led to retardation of fetal development and hypertrophy in the exocrine pancreas of the rat fetuses.

Neonatal handling reduces the number of cells in the medial preoptic area of female rats

Early-life events may induce alterations in neuronal function in adulthood. A crucial aspect in studying long-lasting effects induced by environmental interventions imposed to the animal several weeks before is finding a stable change that could be causally related to the phenotype observed in adulthood. In order to explain an adult trait, it seems necessary to look back to early life and establish a temporal line between events. The neonatal handling procedure is an experimental tool to analyze the long-lasting impact of early-life events. Aside from the neuroendocrine response to stress, neonatal handling also alters the functionality of the hypothalamus-pituitary-gonad (HPG) axis. Reductions in ovulation and surge of the luteinizing hormone (LH) on the proestrous day were shown in female rats. Considering the importance of the medial preoptic area (MPA) for the control of ovulation, the present study aimed to verify the effects of neonatal handling on the numerical density and cell size in the MPA in 11-day-old and 90-day-old female rats. Cellular proliferation was also assessed using BrdU (5-bromo-2`-deoxyuridine) in 11-day-old pups. Results showed that neonatal handling induces a stable reduction in the number of cells and in the size of the cell soma, which were lower in handled females than in nonhandled ones at both ages. Cellular proliferation in the MPA was also reduced 24 h after the last manipulation. The repeated mother-infant disruption imposed by the handling procedure ""lesioned"" the MPA. The dysfunction in the ovulation mechanisms induced by the handling procedure could be related to that neuronal loss. The study also illustrates the impact of an environmental intervention on the development of the brain. (C) 2008 Elsevier B.V. All rights reserved

Growth hormone (GH)/GH receptor expression and GH-mediated effects during early bovine embryogenesis

Pituitary growth hormone (GH) stimulates postnatal growth and metabolism. The role of CH and its receptor (GHR) during prenatal development, however, is still controversial. As shown by reverse transcription polymerase chain reaction (RT-PCR), bovine in vitro fertilization embryos synthesized the transcript of GHR from Day 2 of embryonic life onwards. Real time RT-PCR revealed that synthesis of GHR mRNA was increased 5.9-fold in 6-day-old embryos compared with 2-day-old embryos. Using in situ hybridization, the mRNA encoding GHR was predominantly localized to the inner cell mass of blastocysts. The GHR protein was first visualized 3 days after fertilization. GH-specific transcripts were first detected in embryos on Day 8 of in vitro culture. As shown by transmission electron microscopy, GH treatment resulted in elimination of glycogen storage in 6- to 8-day-old embryos and an increase in exocytosis of lipid vesicles. These results suggest that a functional GHR able to modulate carbohydrate and lipid metabolism is synthesized during preimplantation development of the bovine embryo and that this GHR may be subject to activation by embryonic GH after Day 8.

Natural selection and quantitative genetics of life-history traits in Western women: A twin study

Whether contemporary human populations are still evolving as a result of natural selection has been hotly debated. For natural selection to cause evolutionary change in a trait, variation in the trait must be correlated with fitness and be genetically heritable and there must be no genetic constraints to evolution. These conditions have rarely been tested in human populations. In this study, data from a large twin cohort were used to assess whether selection Will cause a change among women in contemporary Western population for three life-history traits: age at menarche, age at first reproduction, and age at menopause. We control for temporal variation in fecundity (the baby boom phenomenon) and differences between women in educational background and religious affiliation. University-educated women have 35% lower fitness than those with less than seven years education, and Roman Catholic women have about 20% higher fitness than those of other religions. Although these differences were significant, education and religion only accounted for 2% and 1% of variance in fitness, respectively. Using structural equation modeling, we reveal significant genetic influences for all three life-history traits, with heritability estimates of 0.50, 0.23, and 0.45, respectively. However, strong genetic covariation with reproductive fitness could only be demonstrated for age at first reproduction, with much weaker covariation for age at menopause and no significant covariation for age at menarche. Selection may, therefore, lead to the evolution of earlier age at first reproduction in this population. We also estimate substantial heritable variation in fitness itself, with approximately 39% of the variance attributable to additive genetic effects, the remainder consisting of unique environmental effects and small effects from education and religion. We discuss mechanisms that could be maintaining such a high heritability for fitness. Most likely is that selection is now acting on different traits from which it did in pre-industrial human populations.

From aesthetic principles to collective sentiments: The logics of everyday judgements of taste

Contemporary research into the sociology of taste has, following Bourdieu (1984), primarily emphasised the role of social position, or more broadly as implicated int he reproduction of social inequality. We argue that although important, such a preoccupation with the social distribution of objectified tastes--for example in music, literature, and art--has been at the expense of investigating the everyday perceptual schemes and resources used by actors to accomplish a judgement of taste. Our argument is traced using a range of classical and contemporary literature which deals with the personal/collective tension in taste, aesthetics and fashion. We use data from a recent national survey to investigate how a sample of ordinary fashion. We use data from a recent national survey to investigate how a sample of ordinary actors understand the categories of 'good' and 'bad' taste. The analysis shows a strong collective strand in everyday definitions of taste, often linked to moral codes of interpersonal conduct. Also, taste is largely defined by people as a strategy for managing relations with others, and as a mode of self-discipline which relies on the mastery of a number of general principles that are resources for people to position their own tastes within an imagined social sphere. This paper proposes a schematic model which accounts for the range of discriminatory resources used to make judgements of taste.