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1.
The objective was to study the use of ultrasound as a complementary test in the breeding soundness evaluation in male pigs and study the pattern of echogenicity of the testicular parenchyma in boars of different racial groups. Twenty‐six adult boars from four different racial groups were used, 10 from the Piau breed (group 1), four from the commercial and finishing group (group 2), six Pietrain breed (group 3) and six from the Duroc breed (group 4). All animals were evaluated for breeding soundness evaluation and the ultrasound examination of the testicles. The groups of animals that were evaluated showed no difference in the main semen parameters that were evaluated, except for the sperm volume, concentration of the ejaculated sperm and the supravital staining; the lowest figures were for the animals from the Piau breed (group 1). In relation to the testicular biometrics, Duroc animals (group 4) had a greater scrotal width compared to the other groups. But when we assessed the intensity of pixels of the testicles, there was a difference between groups. The groups 2 (finishing animals), 3 (Pietrain) and 4 had no difference between themselves. Group 3 had greater pixel intensity in relation to group 1. Of the 26 animals studied, five showed an abnormality during ultrasound evaluation, like hydrocele, hyperechoic mass in the testicular parenchyma, cyst in the head of the epididymis and the presence of fluid in the head and tail of the epididymis. The various animal groups studied did not differ in the principal reproductive parameters evaluated, showing that despite the great variability of reproductive traits between breeds and within the same breed, the breeding soundness evaluation, the more complete it is, is essential for the selection of breeders and the ultrasonography of the reproductive system becomes an important addition in this examination.  相似文献   
2.
The objectives of this work were to determine the changes in the expression of neuroendocrine markers in Leydig cell by oestradiol treatment, and to determine whether testosterone is able to recover partially the effects of hormonal suppression induced by oestradiol. Adult male rats were injected daily with either 50 microg of oestradiol or oestradiol plus testosterone propionate (25 mg every 3 days) for 15 days. The animals were sacrificed and testicles were dissected and processed by routine histological protocols. FSH and LH serum levels were determined by radioimmunoassay. The visualization of antigens was achieved by the streptavidin-peroxidase immunohistochemical method. Antibodies against chromogranin A (CrA), S-100 protein (S-100), P substance (PS), synaptofisin (SYN), neurofilament protein (NF), gliofibrillary acidic protein (GFAP) and neuron specific enolase (NSE) were used. The mean LH and FSH serum concentrations were consistently suppressed with hormonal treatments. Intermediate filaments (NF and GFAP) showed no difference in their expression. The expression of S-100, NSE and SYN was significantly lower in both hormone-treated groups. In oestradiol-treated rats, the immunoreactivity of CrA and SP decreased significantly but was restored after testosterone supplementation. Although the nature and functions of many of these substances in Leydig cells remain unknown, these results are consistent with the hypothesis that the expression of some neuroendocrine markers is hormonally controlled.  相似文献   
3.
The expression of growth factors was evaluated immunohistochemically in normal and cystic ovaries of sows. The immunohistochemically stained area (IHCSA) was quantified by image analysis to analyse the expression of these proteins in the follicular wall of secondary, tertiary and cystic follicles. IGF‐I immunoreactivity was strong in the granulosa cell layer (GC), moderate in the theca interna (TI) and mild in the theca externa (TE) of the normal follicles. There was severe reduction of the labelling to IGF‐I in the GC of the follicular and luteinized cysts. In the normal follicles, the reactivity for IGF‐II was very similar to pattern noted in IGF‐I. There was reduction of the IHCSAs in the GC of the follicular and luteinized cysts, but the decrease was not significant. The staining of the IGF‐II in the TI and TE of the cysts was increased, in comparison with normal follicles. The IHCSAs for VEGF were higher in the GC and TE of the normal follicles in contrast to TI, but this difference was noted only in the tertiary follicle. The VEGF reactivity increased in the GC of the cysts, in relation to normal follicles. The results of the current study show that the formation of ovarian cysts in sows is associated with alterations in the immunohistochemical expression of some growth factors.  相似文献   
4.
This study aimed to assess the effects of different cooling curves and centrifugation regimes used in cryopreservation protocols on the post‐thaw viability of Piau‐breed wild boar (Sus scrofa) sperm using in vitro assessment tests. Two centrifugations (800  g for 10 min and 2400  g for 3 min) and two cooling curves (conventional cooling using nitrogen vapour – freezing 1 and automated cooling using a programmed freezing machine – freezing 2) were tested. Therefore, the treatments were divided into M3 – centrifugation at 2400  g for 3 min and freezing 2; M10 – centrifugation at 800  g for 10 min and freezing 2; R3 – centrifugation at 2400  g for 3 min and freezing 1; and R10 – centrifugation at 800  g for 10 min and freezing 1. No significant differences (p > 0.05) between treatments occurred post‐thawing regarding the total sperm motility means recorded. The mean values of the different treatments were not different from each other regarding the supravital staining (SV), hypo‐osmotic test (HO), sperm–egg binding assay or sperm morphology. This study showed that both the cooling curve and the centrifugation regime affected the quality of post‐thaw sperm, and centrifugation for shorter times and cooling curves using automated cooling are the most suitable for minimizing sperm injury.  相似文献   
5.
The fabrication and characterization of a glass containing a regular parallel array of submicrometer channels or capillaries are described. The capillaries are arranged in a two-dimensional hexagonal close packing configuration with channel diameters as small as 33 nanometers and packing densities as high as 3 x 10(10) channels per square centimeter. The high-temperature stability of the nanochannel glass array is well suited as a host or template for the formation of quantum confined semiconductor structures or as a mask for massively parallel patterned lithographic applications.  相似文献   
6.
Conservation problems typically involve groups with competing objectives and strategies. Taking effective conservation action requires identifying dependencies between competing strategies and determining which action optimally achieves the appropriate conservation goals given those dependencies. We show how several real-world conservation problems can be modeled game-theoretically. Three types of problems drive our analysis: multi-national conservation cooperation, management of common-pool resources, and games against nature. By revealing the underlying structure of these and other problems, game-theoretic models suggest potential solutions that are often invisible to the usual management protocol: decision followed by monitoring, feedback and revised decisions. The kind of adaptive management provided by the game-theoretic approach therefore complements existing adaptive management methodologies.  相似文献   
7.
The effects of intra-articular injection, on two occasions, 3 weeks apart, of the contrast agent Urografin on the cytological and biochemical characteristics of synovial fluid (SF) were examined in two studies in dogs. The first study provided baseline data in two non-medicated dogs. The second study used a cross-over design whereby 4 dogs received a 7-day oral treatment with either a placebo or meloxicam (0.2 mg/kg body weight daily) with a washout period of 3 weeks, in order to determine the effect of this new non-steroidal anti-inflammatory drug (NSAID) on the response to Urografin injection. SF samples were collected under general anaesthesia prior to and at 24 and 72 h after each Urografin injection. The volume, relative viscosity, white blood cell count and concentrations of protein, lactate dehydrogenase (LDH) and hyaluronic acid of these samples were determined.The results from both studies indicate that intra-articular injection of Urografin provoked a mild local transient inflammatory response, the most dramatic evidence of which was an increase in the white blood cell count in the SF after 24 h. In the second study, comparison of the synovial fluid measurements of the placebo-treated dogs at 24 h after Urografin injection with those prior to injection revealed significant increases in SF volume, white blood cell count, protein concentration and LDH activity and a significant reduction in relative viscosity. At 72 h after injection, only the white blood cell count and relative viscosity were significantly different from the pre-injection values. All of these measurements were, however, associated with high coefficients of variation, which must be taken into account in assessing the usefulness of the model for drug-testing purposes. Nevertheless, the administration of meloxicam significantly reduced the SF volume and white blood cell count at 24 h relative to the effects of concurrent placebo treatment. The general health status of the animals was not disturbed at any time as assessed by clinical and haematological observations. No adverse reactions were observed.Abbreviations LDH lactate dehydrogenase - NSAID non-steroidal anti-inflammatory drug - SF synovial fluid - WBC white blood cell count  相似文献   
8.
We hypothesized that the inclusion of flaxseed in the diets of lactating dairy cows will increase urinary and fecal concentrations of the lignans, secoisolariciresinol diglycoside (SDG), enterolactone and enterodiol, reduce intrafollicular concentrations of IGF-I and estradiol, and subsequently reduce estradiol and oxytocin receptor expression in the endometrium. To test this hypothesis, 27 cycling, lactating Holstein cows were assigned to 1 of 3 diets supplemented with saturated fatty acids (SAT), flax (FLX), or sunflower (SUN) seed. Rations were formulated to provide 750 g supplemental fat/cow/d in all dietary groups. Ovulation (Day 0) was synchronized, and 5 d later, follicles>8 mm were ablated by an ultrasound-guided procedure in all cows. Samples of blood (Days 0 to 14), follicular fluid (Day 5 and 15), endometrium (Day 15), as well as urine and feces were collected in a subset of the animals. The fecal concentrations of SDG and enterodiol were higher (P<0.05) in cows fed FLX than in those fed SAT or SUN. Enterodiol increased (P<0.05) in urine samples of cows fed FLX, compared to those of cows fed SUN. However, follicular estradiol concentrations on Day 5 and 15 and endometrial concentrations of estradiol and oxytocin receptors on Day 15 did not differ among the dietary groups. Mean plasma progesterone concentrations were higher (P<0.05) in cows fed FLX and SUN than in those fed SAT. In summary, a diet supplemented with flaxseed increased the concentrations of SDG and enterodiol in feces, as hypothesized, but did not alter intrafollicular concentrations of IGF-I or estradiol, or endometrial populations of oxytocin or estrogen receptors in lactating dairy cows.  相似文献   
9.
The purpose of this study was to estimate the expression and relative amounts of estrogen (ER) and progesterone receptors (PR) and their isoforms as well as heat shock protein 70 (HSP70) in ovaries of rats with induced cystic ovarian disease (COD). Primary, secondary, tertiary, atretic and cystic follicles were evaluated by immunohistochemistry and total ovarian proteins were analyzed by Western blot. In the granulosa layer, growing and cystic follicles in the treated group have a higher expression of ERα than growing follicles of control individuals. In the theca interna layer, tertiary follicles presented a significantly higher expression of ERα in the treated group. An increase in total ERα protein was detected in the treated group. Granulosa cells of all growing, atretic and cystic follicles show a lower expression of ERβ in animals with COD, and the total protein expression of ERβ was lower in this group. The expression of PR was lower in the granulosa cell layer of tertiary and cystic follicles in treated animals, and theca interna layer had less intense immunostaining in this group. Although there were no differences in the expression of PR-B by Western blotting, the expression of PR-A was higher and the expression of PR-C was smaller in the treated group. An intense HSP70 immunostaining was observed in the cells of cystic follicles. By Western blotting, higher protein expression of HSP70 was detected in the ovarian samples of the control group than those of the treated ones. Ovaries of animals with COD exhibited an altered steroid receptor expression and subtype balance as compared with control animals, and an increase in HSP70 immunoexpression.  相似文献   
10.
Two recent studies have suggested that divergent mitochondrial lineages may be present within spirostreptid genera such as Bicoxidens Attems, 1928. Bicoxidens, similar to many other endemic soil invertebrates, exhibits low dispersal capabilities and strict microclimate habitat preferences, attributes that often lead to geographic isolation. Given that prolonged geographic isolation often lays the foundation for population genetic differentiation, genetic divergence and possibly speciation, there was good reason to suspect that Bicoxidens may consist of several distinct lineages. On this basis, the mitochondrial cytochrome c oxidase subunit 1 (COI) was used to reconstruct the phylogeny of Bicoxidens and reveal divergent lineages within the genus. Maximum likelihood and Bayesian inference analyses recovered a paraphyletic Bicoxidens phylogram with divergent lineages present in three species – B. friendi, B. flavicollis and B. brincki – suggesting high genetic diversity within the genus. Bayesian genetic cluster analyses suggested the presence of multiple distinct mitochondrial lineages within the genus with four identified in B. flavicollis alone. It was therefore concluded that the divergent lineages observed among Bicoxidens populations may suggest the presence of hidden species.  相似文献   
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