Composição corporal e puberdade de leitoas alimentadas com níveis alto e baixo de proteína na dieta

Com o objetivo de verificar alterarações na composição corporal, diferentes níveis protéicos (12 e 18% PB) foram utilizados na dieta de leitoas de reposição, dos 100 aos 221 dias de idade. Durante esse período foram avaliados o peso corporal, espessura de toucinho (ET), manifestação de estro, características do trato reprodutivo e o balanço nitrogenado. Para a determinação do balanço nitrogenado, as leitoas foram submetidas a dois ensaios de digestibilidade (aos 136 e aos 201 dias de idade). em ambos os ensaios, as leitoas alimentadas com 18% PB apresentaram maior ingestão, retenção e excreção de nitrogênio e maiores níveis de uréia plasmática e urinária (P<0,001). A eficiência da utilização de nitrogênio não foi influenciada pelo nível protéico da dieta (P>0,05). Houve redução de 48% na excreção de nitrogênio com a dieta menos protéica. Leitoas alimentadas com 12% PB apresentaram maior ganho de ET (7,4 mm) em comparação às alimentadas com 18% PB (4,5 mm), dos 100 aos 207 dias de idade (P<0,02). O peso corporal, peso do útero, comprimento dos cornos uterinos e número de corpos lúteos não foram afetados pelo nível de proteína na dieta. A taxa de detecção de estro, até 25 dias após a exposição das leitoas ao cachaço, foi semelhante para as fêmeas recebendo 12% (71%) e 18% PB (75%). Os níveis de proteína da dieta afetaram a composição corporal das fêmeas sem que o peso final, o desencadeamento da puberdade e características do trato reprodutivo fossem afetados, indicando que dietas de baixa proteína podem ser utilizadas como estratégia para aumentar a espessura de toucinho de leitoas de reposição.

Additive genetic relationships between scrotal circumference, heifer pregnancy, and stayability in Nellore cattle

Scrotal circumference data from 47,605 Nellore young bulls, measured at around 18 mo of age (SC18), were analyzed simultaneously with 27,924 heifer pregnancy (HP) and 80,831 stayability (STAY) records to estimate their additive genetic relationships. Additionally, the possibility that economically relevant traits measured directly in females could replace SC18 as a selection criterion was verified. Heifer pregnancy was defined as the observation that a heifer conceived and remained pregnant, which was assessed by rectal palpation at 60 d. Females were exposed to sires for the first time at about 14 mo of age (between 11 and 16 mo). Stayability was defined as whether or not a cow calved every year up to 5 yr of age, when the opportunity to breed was provided. A Bayesian linear-threshold-threshold analysis via Gibbs sampler was used to estimate the variance and covariance components of the multitrait model. Heritability estimates were 0.42 +/- 0.01, 0.53 +/- 0.03, and 0.10 +/- 0.01, for SC18, HP, and STAY, respectively. The genetic correlation estimates were 0.29 +/- 0.05, 0.19 +/- 0.05, and 0.64 +/- 0.07 between SC18 and HP, SC18 and STAY, and HP and STAY, respectively. The residual correlation estimate between HP and STAY was -0.08 +/- 0.03. The heritability values indicate the existence of considerable genetic variance for SC18 and HP traits. However, genetic correlations between SC18 and the female reproductive traits analyzed in the present study can only be considered moderate. The small residual correlation between HP and STAY suggests that environmental effects common to both traits are not major. The large heritability estimate for HP and the high genetic correlation between HP and STAY obtained in the present study confirm that EPD for HP can be used to select bulls for the production of precocious, fertile, and long-lived daughters. Moreover, SC18 could be incorporated in multitrait analysis to improve the prediction accuracy for HP genetic merit of young bulls.

In vitro conservation and low cost micropropagation of Cochlospermum regium (Mart. Ex. Scharank)

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

The structure of the human temporomandibular joint disc: A scanning electron microscopy study

The articular disc of the temporomandibular joint was studied in fetuses (16 to 39 weeks of intrauterine life), infants (up to 4 months of age), dentulous adults (aged 30 to 39 years), and completely edentulous adults (aged 60 to 69 years) by scanning electron microscopy. The constituent bundles of collagen fibers were stratified and were oriented anteroposteriorly, laterolaterally, and obliquely in the middle portion of the disc. A ring of laterolateral bundles constituted the main feature of the thick posterior portion. In the anterior portion of the disc, the fibers were anteroposteriorly and obliquely oriented. On the superior and inferior surfaces of the disc, a thin layer of perpendicularly arranged collagen fibers covered the underlying, thick, laterolateral oriented collagen fibers.

A kinetic model of phosphorus metabolism in growing goats

The effect of increasing phosphorus (P) intake on P utilization was investigated in balance experiments using 12 Saanen goats, 4 to 5 mo of age and weighing 20 to 30 kg. The goats were given similar diets with various concentrations of P, and 32P was injected to trace the movement of P in the body. A P metabolism model with four pools was developed to compute P exchanges in the system. The results showed that P absorption, bone resorption, and excretion of urinary P and endogenous and fecal P all play a part in the homeostatic control of P. Endogenous fecal output was positively correlated to P intake (P < .01). Bone resorption of P was not influenced by intake of P, and P recycling from tissues to the blood pool was lesser for low P intake. Endogenous P loss occurred even in animals fed an inadequate P diet, resulting in a negative P balance. The extrapolated minimum endogenous loss in feces was .067 g of P/d. The minimum P intake for maintenance in Saanen goats was calculated to be .61 g of P/ d or .055 g of P/(kg.75·d) at 25 kg BW. Model outputs indicate greater P flow from the blood pool to the gut and vice versa as P intake increased. Intake of P did not significantly affect P flow from bone and soft tissue to blood. The kinetic model and regressions could be used to estimate P requirement and the fate of P in goats and could also be extrapolated to both sheep and cattle.

The ultrastructural aspects of vitellogenesis or oocyte secondary growth in Serrasalmus spilopleura (Teleostei, Characiformes, Serrasalminae)

Oocyte secondary growth in S. spiloleura corresponds to the period in which different vesicular structures are formed, including the cortical alveoli and the yolk granules. The oocytes with cortical alveolus formation show vesicular structures with filamentous content in the cortical cytoplasmic region, which are the cortical alveolus precursors. In these oocytes, electron-dense vesicles of heterogenous content are dispersed in the inner cytoplasmic region and their nuclei are irregular, showing many nucleoli of different sizes. The oocytes in vitellogenesis are filled with many vesicles. The cortical alveolus precursors are in the peripheral region, and electron-dense granules are seen near to the nucleus. These fuse and form yolk granules. The oocytes in vitellogenesis show a very irregular nucleus that has nucleoli of different sizes. In the oocytes in final vitellogenesis, the yolk granules are scattered throughout the cytoplasm, displacing the cortical alveoli toward cell periphery. The nucleus is similar to the other stages.

Mating influence in the ovary differentiation in adult queens of Apis mellifera L. (Hymenoptera, Apidae)

The present results show that in the ovarioles of a newly emerged (0 day) queen of A. mellifera only two regions may be distinguished: a proximal, short germarium and a very long distal, terminal filament. As the queen matures and gets ready for the nupcial flight, the germarium increases in lenght, advancing towered the distal end, as the terminal filament shortens. The ovarioles of queens ready to mate (6 to 8 days old) have, already one or two ovarian follicles, i.e. a very short proximal vitellarium, but a real vitellogenesis only starts after the fecundation. If the queen does not mate the ovarioles structure is disrupted (12-16 days old). In mated queen eggs the ovarioles present three differentiated regions, from the apice to the basis: a short terminal filament, a medium size germarium, and a very long basal vitellarium. As the eggs are laid, the emptied follicle collapses, degenerates and produces a corpus luteum.

Poisoning of mice by Baccharis coridifolia: An experimental model

The poisonous plant Baccharis coridifotia causes necrosis in lymphoid tissues and the gastrointestinal tract of cattle, horses, sheep and rabbits. An experimental poisoning of mice was undertaken to establish an experimental model in a laboratory animal specie. A single 5 to 8-g/kg dose of a suspension of the plant was administered by gavage to II mice. To 3 other control mice, the same volume of water was administered. Plant-dosed mice manifested clinical effects after 12 h: tachipnea, trembles, dehydration and prostration. Most of the dosed mice died 14 to 33 h after plant administration-3 survived for 12 d. Six mice had remarkable necrosis of the germinative center of secondary follicles in lymph nodes and spleen; 3 mice had necrosis of lymphoid tissues in intestine and thymus. Mice reproduce most of the lesions observed in naturally poisoned cattle and the use of this specie as an experimental model is valid.

Correlações entre morfometria ovariana e hormônios em vacas zebus não prenhes

The study of ovarian morphometry is directly related to its practical applications to interpret the examination of the reproductive tract of the cow. The objective of this work was to study the ovarian morphometry collected in slaughterhouse and correlations between corpus luteum area, progesterone and cortisol in no pregnant zebu cows. One hundred fourteen pairs of ovaries were collected from slaughterhouse, measured in thickness, length, width and volume, diameter and volume of the follicle, diameter and area of the corpus luteum. Significative difference (p<0.05) were observed for widths of (1.95 cm and 1.83 cm) and volume (p<0.05) of 7.26 ml and 6.23 ml of left and right ovaries respectively. For size and volume of follicles, and diameter and area of the corpus luteum, there was no significative difference between the sides. There was correlation of 0.46 (p<0.01) between left ovary volume × luteum corpus area, in the presence of follicles with diameters equal or greater than 9 mm, the corpus luteum of the massive and protuberant type were present in 23 (43.39%) of 53 ovaries, predominating in relation to type of massive and incluse 16 (30.18%). There were no significative correlation between corpus luteum area × progesterone, corpus luteum area × cortisol and progesterone × cortisol. In conclusion, the presence of the included corpus luteum in zebu cows could result in error during the rectal palpationexam to estimate the ovarian activity.

Mammary benign neoplasm diagnosed by fine needle aspiration biopsy in a guinea pig (Cavia porcellus)

Cytology is a well established research technique in human and veterinary medicine, but it is rarely used in small rodents. Spontaneous tumors are relatively uncommon in guinea pigs and those described in literature include a variety of organs like skin and subcutis, respiratory and reproductive tract, endocrine and hematopoietic system, and mammary gland. The objective of this article was to describe the use of the fine needle aspiration biopsy technique (FNAB) on evaluation of a mammary neoplasm in a guinea pig and describe the main cytological findings for the first time in literature.

Mare's folliculogenesis: Assessment of ovarian and perifollicular vascular perfusion by doppler ultrasound

Background: Ultrasound Doppler is a new technology that has recently been used in large animal reproduction. As the conventional ultrasound (B-mode) it is a noninvasive technique, but with the advantage of allows the assessment of the hemodynamic of reproductive tract in real time. The observation of important features of the vascularization and changes that occur during physiological processes that were not previously seen on B-mode encourage a reassessment of the concepts already established on the events of the reproductive physiology of animals and their applications. Review: In attempt to re-understand the equine reproductive physiology and finding practical uses to this new technique, authors showed that, during the follicular deviation, features are observed by Doppler before being observed under B-mode ultrasound like changes in the speed of the blood flow two days before deviation of the follicle size and one day before the increase in blood flow area of the follicular wall. According to another study ovulation is characterized by a decreased blood flow of the follicular wall in the last four hours preceding it, as well as the serration of the granulosa layer and formation of a non vascularized apex, but in our ongoing study, the ability to decrease the vascularity was not found. Very vascularized follicles are associated with higher rates of oocyte maturation and pregnant that does less vascularized follicles in the preovulatory phase. Those follicles that have septated evacuation (or prolonged) showed more vascularization and serration of the granulosa one hour before ovulation than follicles that ovulate normally, and this vascularization includes the apex of the follicle, the follicular wall portion that is not vascularized in normal ovulation. Another study reported that hemorrhagic follicles have better vascularization of the follicular wall on the days preceding ovulation than follicles destined to ovulate. Some authors also showed that anovulatory follicles grow in size at the same rate as ovulatory follicles, but the percentage of vascularization of its wall is much smaller at 35 mm. Another study characterized that the vascular wall of the follicle that results in the first ovulation of the year is much smaller on the day before ovulation than the number of vessels present in a follicle that will ovulate in the middle of the breeding season. In these cases, the use of Doppler ultrasound can help to prevent economic losses as insemination of mares in cycles that are not able of resulting in pregnancy. This review aims to gather the information found in the literature about the characteristics of follicular hemodynamic of mares taking into account moments of deviation in follicle size, ovulation, ovulation failure and follicular viability. Conclusion: The Doppler technology has the potential to provide important information about the follicular environment and thus be used in practice in search of the perfect equine reproductive management, achieving better utilization of genetic material and increasing the financial return. The use of this new tool opens a large area for several interesting studies that will contribute to the knowledge of the physiological events of the mare for that this technique can soon be effectively applied.

Caffeine reduces cadmium accumulation in the organism and enhances the levels of antioxidant protein expression in the epididymis

The aim of this study was to investigate the effects of caffeine (20. mg/L) intake on cadmium (15. mg/L) accumulation in the rat blood, testes, epididymis and prostate as well as cadmium-induced changes to the antioxidant defense system of the epididymis. Caffeine reduced the cadmium concentration in all tissues analyzed. Meanwhile, cadmium reduced catalase activity and increased superoxide dismutase (SOD) activity in the epididymis. Caffeine increased SOD activity, catalase and glutathione tissue expression and sustains the cadmium's effect on catalase and GSP-Px activity. No differences in the expression of metallothionein and lipid peroxidation were observed among the different treatments in the epididymis. In conclusion, low doses of cadmium alter the antioxidant enzymatic profile of the epididymis, but not induced oxidative lipid damage. Caffeine intake reduces overall cadmium accumulation in the organism and enhances the levels of antioxidant protein expression in the epididymis, thus exerting a protective effect against this metal. © 2012 Elsevier Inc.

NF-kB overexpression and decreased immunoexpression of AR in the muscular layer is related to structural damages and apoptosis in cimetidine-treated rat vas deferens

Background: Cimetidine, histamine H2 receptors antagonist, has caused adverse effects on the male hormones and reproductive tract due to its antiandrogenic effect. In the testes, peritubular myoid cells and muscle vascular cells death has been associated to seminiferous tubules and testicular microvascularization damages, respectively. Either androgen or histamine H2 receptors have been detected in the mucosa and smooth muscular layer of vas deferens. Thus, the effect of cimetidine on this androgen and histamine-dependent muscular duct was morphologically evaluated.Methods: The animals from cimetidine group (CMTG; n=5) received intraperitoneal injections of 100 mg/kg b.w. of cimetidine for 50 days; the control group (CG) received saline solution. The distal portions of vas deferens were fixed in formaldehyde and embedded in paraffin. Massońs trichrome-stained sections were subjected to morphological and the following morphometrical analyzes: epithelial perimeter and area of the smooth muscular layer. TUNEL (Terminal deoxynucleotidyl-transferase mediated dUTP Nick End Labeling) method, NF-kB (nuclear factor kappa B) and AR (androgen receptors) immunohistochemical detection were also carried out. The birefringent collagen of the muscular layer was quantified in picrosirius red-stained sections under polarized light. The muscular layer was also evaluated under Transmission Electron Microscopy (TEM).Results: In CMTG, the mucosa of vas deferens was intensely folded; the epithelial cells showed numerous pyknotic nuclei and the epithelial perimeter and the area of the muscular layer decreased significantly. Numerous TUNEL-labeled nuclei were found either in the epithelial cells, mainly basal cells, or in the smooth muscle cells which also showed typical features of apoptosis under TEM. While an enhanced NF-kB immunoexpression was found in the cytoplasm of muscle cells, a weak AR immunolabeling was detected in these cells. In CMTG, no significant difference was observed in the birefringent collagen content of the muscular layer in comparison to CG.Conclusions: Cimetidine induces significant damages in the epithelium; a possible antiandrogenic effect on the basal cells turnover should be considered. The cimetidine-induced muscle cells apoptosis confirms the susceptibility of these cells to this drug. The parallelism between enhanced cytoplasmic NF-kB immunolabeling in the damaged muscular tissue and muscle cell apoptosis suggests that this drug may avoid the translocation of NF-kB to the nucleus and interfere in the control of NF-kB-mediated smooth muscle cell apoptosis. The decreased immunoexpression of ARs verified in the damaged muscular tissue reinforces this possibility. © 2013 Koshimizu et al.; licensee BioMed Central Ltd.

Melatonin and ethanol intake exert opposite effects on circulating estradiol and progesterone and differentially regulate sex steroid receptors in the ovaries, oviducts, and uteri of adult rats

Chronic ethanol intake is associated with sex hormone disturbances, and it is well known that melatonin plays a key role in regulating several reproductive processes. We report the effects of ethanol intake and melatonin treatment (at doses of 100. μg/100. g. BW/day) on sex hormones and steroid receptors in the ovaries, oviducts and uteri of ethanol-preferring rats. After 150 days of treatment, animals were euthanized, and tissue samples were harvested to evaluate androgen, estrogen, progesterone and melatonin receptor subunits (AR, ER-α and ER-β, PRA, PRB and MT1R, respectively). Melatonin decreased estradiol (E2) and increased progesterone (P4) and 6-sulfatoxymelatonin (6-STM), while an ethanol-melatonin combination reduced both P4 and E2. Ovarian AR was not influenced by either treatment, and oviduct AR was reduced after ethanol-melatonin combination. Oviduct ER-α, ER-β and uterine ER-β were down-regulated by either ethanol or melatonin. Conversely, ovarian PRA and PRB were positively regulated by ethanol and ethanol-melatonin combination, whereas PRA was down-regulated in the uterus and oviduct after ethanol consumption. MT1R was increased in ovaries and uteri of melatonin-treated rats. Ethanol and melatonin exert opposite effects on E2 and P4, and they differentially regulate the expression of sex steroid receptors in female reproductive tissues. © 2013 Elsevier Inc.