Effects of sex and age on genotype x environment interaction for beef cattle body weight studied using reaction norm models

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

OVARIAN HISTOLOGY and FOLLICULAR SCORE IN FEMALE RATS TREATED WITH NANDROLONE DECANOATE and SUBMITTED TO PHYSICAL EFFORT

The study was conducted to analyze the histology of the ovaries of adults rats treated with steroids, and submitted or not to physical effort. The control group consisted of females submitted to physical effort and sedentary females, both of which received a physiological solution of 0.9% saline. Treated females, sedentary or not, received 6 mg/kg of body weight of nandrolone decanoate. The steroid and physiological solution were administered intraperitoneally, with a single injection per week for 4 consecutive weeks. The applied physical effort was swimming (20 minutes daily, 5 days/week, for the 4 weeks of treatment). Serial sections (5 mu m) of ovaries were prepared for histological evaluation and follicular score. The weight of ovaries and hypophysis, the number of antral and atretic follicles, and the area of corpus luteum were all affected by the steroids. In the ovaries of the control groups, well-developed corpus luteum was observed. In the treated groups, the cortical stroma was occupied by ovarian interstitial tissue. The females treated with steroids presented estral acyclicity. The use of nandrolone decanoate, whether associated with physical effort or not, affected the morphological pattern of the ovaries.

Exercise training attenuates acute hyperalgesia in streptozotocin-induced diabetic female rats

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Levels of DNA damage in blood leukocyte samples from non-diabetic and diabetic female rats and their fetuses exposed to air or cigarette smoke

dThe objective of the present study was to evaluate DNA damage level in blood leukocytes from diabetic and non-diabetic female Wistar rats exposed to air or to cigarette smoke, and to correlate the findings with levels of DNA damage detected in blood leukocyte samples from their fetuses. A total of 20 rats were distributed into four experimental groups: non-diabetic (control; G1) and diabetic exposed to filtered air (G2): non-diabetic (G3) and diabetic (G4) exposed to cigarette smoke. Rats placed into whole-body exposure chambers were exposed for 30 min to filtered air (control) or to tobacco smoke generated from 10 cigarettes, twice a day, for 2 months. Diabetes was induced by a pancreatic beta-cytotoxic agent, streptozotocin (40 mg/kg b.w.). At day 21 of pregnancy, each rat was anesthetized and humanely killed to obtain maternal and fetal blood samples for genotoxicity analysis using the alkaline comet assay. G2, G3 and G4 dams presented higher DNA damage values in tail moment and tail length as compared to G1 group. There was a significant positive correlation between DNA damage levels in blood leukocyte samples from G2 and G3 groups (tail moment); G3 and G4 groups (tail length) and G3 group (tail intensity) and their fetuses. Thus, this study showed the association of severe diabetes and tobacco cigarette smoke exposure did not exacerbate levels of maternal and fetal DNA damages related with only diabetes or cigarette smoke exposure. Based on the results obtained and taking into account other published data, maternal diabetes requires rigid clinical control and public health and education campaigns should be increased to encourage individuals, especially pregnant women, to stop smoking. (C) 2008 Elsevier B.V. All rights reserved.

Modifying Effects of Lemongrass Essential Oil on Specific Tissue Response to the Carcinogen N-Methyl-N-Nitrosurea in Female BALB/c Mice

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

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

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Female reproductive system of the decapitating fly Pseudacteon wasmanni Schmitz (Diptera : Phoridae)

Pseudacteon wasmanni is a South American decapitating fly that parasitizes workers of Solenopsis fire ants. We used light microscopy (historesin serial-sectioning stained with Haematoxylin/Eosin) and scanning electron microscopy to show and analyze internal and whole external views of the female reproductive system. All specimens analyzed (n = 9) by light microscopy showed post-vitellogenic oocytes inside the ovaries. The lack of typical follicles (oocyte-nurse cell complexes) in all specimens suggests that oogenesis occurs during the pupal stage. The total number of eggs found ranged from 31 to 280 (X = 142 +/- 73, SD). The egg has a slugform or torpedo shape (about 130 by 20 mum) with a pointed apex at the posterior pole as defined by the fly; the micropyle appears to be in a depression or invagination at the anterior pole. An acute hypodermic-like ovipositor is evaginated from the hard sclerotized external genitalia during egg laying. The existence of a muscular bulb associated with the end of the common oviduct suggests that the egg is injected into the ant's body by a strong contraction of the bulb which probably is stimulated by bending of several ventral sensilla. During contraction, the abdomen extends out along a large fold between the sixth and seventh tergites in such a way that the sclerotized genitalia is rotated ventrally into a slightly anterior orientation in preparation for oviposition. (C) 2003 Elsevier B.V. Ltd. All rights reserved.

Vitellogenin content in fat body and ovary homogenates of workers and queens of Melipona quadrifasciata anthidioides during vitellogenesis

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

More than one inseminated female in colonies of the independent-founding wasp Mischocyttarus cassununga von Ihering (Hymenoptera, Vespidae)

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Seasonal variation in body size of tropical anuran amphibians.

Most anurans are considered short lived reproducing only once, with adult size being an important factor contributing to mating success. We sampled anurans with 30 pitfall traps in three forest patches of the northwestern São Paulo State, Brazil, throughout one year. Our objective was to analyze the variation in anuran body size between the dry and rainy season. Our hypothesis is that anurans registered during the rainy season will be larger than conspecifics registered during dry season, since there is a selective advantage in having a larger body size during reproduction activity. The most abundant species registered in the patches were Eupemphix nattereri, Physalaemus cuvieri and Leptodactylus podicipinus. Males and females of E. nattereri and P. cuvieri recorded in the rainy season were larger than of those captured in the dry one. In contrast, males of L. podicipinus were larger in the dry season than in the rainy season. Besides, the operational sex ratio (OSR) in the breeding season was biased towards males in these three species with, respectively, 4.66, 3.2 and 1.87 males per female. Our results suggest that probably body size variation between different seasons is a consequence of individuals' turnover between rainy seasons. Lower individuals captured in the dry season, would be reproductively active adults in the next breeding season.

Ingestive behavior and performance of female lambs grazing on Marandu palisadegrass under different stocking rates

The ingestive behavior and performance of female lambs grazing on Marandu pasture submitted to different stocking rates during the rainy and transition season were evaluated. The experimental area with 4,500 m² was divided into 45 paddocks of 100 m². Twenty-seven Santa Ines female lambs (purebred) with 4 months age and 22 kg of initial body weight were distributed in a completely randomized design, with nine replicates. Lambs were divided into 9 groups with the same initial weight and submitted to three stocking rates: 2, 3 and 4 lambs/paddock, which corresponded to 40, 60 and 80 lambs/ha, respectively. Each group of animals had a module of five paddocks, managed on intermittent grazing system, with 7 days of occupation and 28 d of rest. Increase on time grazing and reduction on time ruminating and resting were observed as stocking rates increased. There was 14% raise in time grazing and 41% decline on time resting by lambs subjected to the highest stocking rate compared with those in the lower stocking rate. The number of animals/ha promoted linear effect on average daily gain, which was higher for animals in the lowest stocking rate of 90 g/d. For gain per area, the best result was obtained with 60 animals/ha featuring an average value of 426 kg/ha.

Testosterone stimulates growth and secretory activity of the female prostate in the adult gerbil (Meriones unguiculatus)

The prostate of the female gerbil (Meriones unguiculatus) is similar to the human female prostate (Skene gland) and, despite its reduced size, it is functional and shows secretory activity. However, virtually nothing is known about its physiological regulation. This study was thus undertaken to evaluate the behavior of the gerbil female prostate in a hyperandrogenic condition. Adult females received subcutaneous injections of testosterone cypionate (1 mg/kg body weight every 48 h) up to 21 days. Circulating levels of testosterone and estradiol were monitored, and the prostate and ovaries subjected to structural and immunocytochemical analyses. The treatment resulted in sustained high levels of circulating testosterone, and caused a transient increase in estradiol. There was an increase in epithelial cell proliferation accompanied by significant reorganization of the epithelium and an apparent reduction in secretory activity, followed by a progressive increase in luminal volume density and accumulation of secretory products. Immunocytochemistry identified the expression of androgen receptor and a prostate-specific antigen (PSA)-related antigen in prostatic epithelial cells. A circulating PSA-related antigen was also found, and its concentration showed strong negative correlation with circulating estrogen. Epithelial dysplasia was detected in the prostate of treated females. Analysis of the ovaries showed the occurrence of a polycystic condition and stromal cell hyperplasia. The results indicate that testosterone has a stimulatory effect on the female prostate, inducing epithelial cell proliferation, differentiation, secretory activity, and dysplasia. The results also suggest that prostatic growth and activity, polycystic ovaries, and ovarian stromal cell hyperplasia are related to a hyperandrogenic condition in females.

Net energy, protein and macrominerals requirements for 70 to 120 day old female rabbits

In order to determine the net energy, protein and macrominerals requirements of 70 to 120 day old, 52 female White New Zealand rabbits, weighing 1900g +/- 40g were used. At the beginning of the experimental period, 14 of the 52 young does were slaughtered and the 38 remaining animals were kept under two dietary management: ad libitum and restricted feeding. Slaughters were performed to determine each nutrient body content. The weight gain nutrient requirements depicted by the quantities of each nutrient stored into the body were obtained by applying the regression equation, which estimate the empty body nutrient content logarithm as a function of the empty body weight logarithm, as described by ARC (1980). By determining the heat production logarithm at the zero level of metabolizable energy intake, the maintenance net energy requirement was estimated to be 45.31 Kcal/day/Kg(0.75) the mean net energy. protein, calcium, phosphorous, sodium, magnesium and potassium requirements for each gram of weight gain per day were estimated to be, 2.51 Kcal, 0.21g, 0.02g, 0.005g, 0.001g, 0.0004g and 0.002g, respectively.

Effects of prenatal exposure to deltamethrin on forced swimming behavior, motor activity, and striatal dopamine levels in male and female rats

The effects of prenatal exposure of rat pups to 0.08 mg/kg deltamethrin (DTM) on physical, reflex and behavioral developmental parameters, on forced swimming and open-field behaviors, and on striatal monoamine levels at 60 days of age were observed. Maternal and offspring body weight, physical and reflex development were unaffected by the exposure to the pesticide. At 21 days of age, open-field locomotion frequency and immobility duration of male and female offspring were not different between control and exposed animals. However, male rearing frequency was increased in experimental animals. A decreased immobility latency to float and in general activity after the swimming test in male offspring was observed at adult age; no interference was detected in the float duration during the swimming test. In addition, these animals presented higher striatal 3,4-dihydroxyphenylacetic acid (DOPAC) levels without modification in dopamine (DA) levels and an increased DOPAC/DA ratio. These data indicate a higher activity of the dopaminergic system in these animals. Noradrenaline (NA) levels were increased, while MHPG levels were not detectable in the system studied. Serotonin (5-HT) and 5-hydroxyindolacetic acid (5-HIAA) levels, as well as the homovanillic acid (HVA)/DA ratio, were not modified by the exposure to the pesticide. No changes were observed in swimming and open-field behaviors nor were there any changes in striatal monoamines or their metabolites in the female experimental group. In relation to the pesticide formula, the present data showing that prenatal exposure to DTM alters latency to float and the activity of striatal dopaminergic system might reflect a persistent effect of the pesticide on animal motor activity, mainly in males. on the other hand, the decrease in general activity observed in experimental male rats suggests higher levels of emotionality induced by previous exposure to the swimming behavior test in relation to control animals. Data gathered in the present study may be important for the assessment of the safety of pyrethroid insecticides. (C) 2001 Elsevier B.V. All rights reserved.

Foreign body in the tracheobronchial tree

A 20-year experience with the treatment of 74 patients (83.8% children) for foreign body aspiration is reviewed. The object of this review is to show the clinical manifestations, the radiological findings, the nature and distribution in the bronchial tree, and complications due to longstanding (months or years) foreign bodies in the bronchial tree. The most common foreign bodies found were peanuts (13.5%), corn (13.5%), and beans (13.5%). The most frequent clinical manifestation was choking (67.5%), and the most frequent radiological finding was atelectasis (41.8%). The most serious complication was bronchiectasis needing resection in six patients who had the foreign body retained for years in the bronchial tree. In conclusion, in spite of an obvious foreign body in the tracheobronchial tree many cases are not diagnosed, and a longstanding foreign body in the airway may be responsible for irreversible complications.