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71.
The lectin‐binding pattern was compared in the normal and pathological uterus of sows during the ovarian cycle. The following biotinylated lectins were used: Con A, DBA, SBA, PNA, RCA‐I, UEA‐I and WGA. Glycoconjugate labelling showed differences between phases of ovarian cycle and presence of morphologic lesions. Cystic endometrial hyperplasia increased the RCA‐I reaction in the apical region of the glandular epithelium. There was higher intensity of labelling of WGA in the glandular epithelium in uteri with endometritis. In addition, increased Con A binding in the glandular epithelium and mild reduction of UEA‐I reactivity in the glycocalyx of the glandular epithelium were detected in the cases of endometritis. The results of this study show that morphologic alterations modify the sugar pattern in the porcine uterus. These modifications in glycoconjugates may be one of the reasons for decreased fertility in sows.  相似文献   
72.
Uterine Insemination with a Standard AI Dose in a Sow Pool System   总被引:1,自引:0,他引:1  
The effect of uterine AI with a standard dose of spermatozoa on fertility of the sow was studied in a field trial. The trial involved a sow pool system with 440 sows using AI as the primary method of breeding. Sows were twice a day checked for oestrus symptoms by back pressure test in front of a boar on days 3–6 after weaning. When in standing heat, sows were randomly allocated into either a uterine insemination group (UTER, n = 157) or standard AI group (CONT, n = 169) and bred accordingly using 3 billion spermatozoa in 80 ml of extender. In both treatment groups, insemination was repeated once if the sow was still receptive 24 h later. Using pregnancy (farrowed or not) and live‐born litter size as the outcome variables, a logistic and linear regression approach, respectively, was taken to study the effect of the following factors: treatment (UTER vs CONT), AI operator, breed, satellite herd preceding weaning, parity, weaning‐to‐oestrus interval and length of lactation. Overall, live‐born litter size was 11.3 ± 2.9, repeat breeding rate 4.2% and farrowing rate 91.2%. In the UTER group, 93.6% of inseminated sows farrowed, whereas farrowing rate for the CONT group was 88.8% (p = 0.13). Intrauterine insemination with a standard AI dose did not result in a significant improvement in the live‐born litter size (11.5 ± 2.8 for the UTER and 11.1 ± 3.0 for the CONT sows, respectively, p = 0.13). However, the preceding satellite herd had a highly significant effect on the live‐born litter size (12.4 ± 2.6; 11.1 ± 2.9; 10.8 ± 2.9 and 10.9 ± 2.9 for the four satellite herds, p < 0.01). We conclude that uterine insemination did not have a significant effect on live‐born litter size and farrowing rate and we also conclude that satellite herd appears to have a major effect on fertility in a sow pool system.  相似文献   
73.
Bovine respiratory syncytial virus (BRSV) infection is an important part of the calf pneumonia complex, occasionally affecting even adult cattle. However, the pathogenicity of BRSV in animals older than 6 months is often neglected. Finland is free of many contagious diseases in farm animals, and this gives a good opportunity to study the effects of specific pathogens on bovine reproduction. This report describes the deteriorating effects of BRSV epizootics on sperm morphology and fertility of young dairy bulls (n = 79) at a bull station. More than half of the young bulls had a clinical respiratory disease caused by BRSV during their quarantine when they were 6 months old. Four of seven subsequent quarantine groups were affected. Six months later, when these seropositive bulls (n = 54) came into semen production, they had poorer sperm morphology, and the proportion of normal spermatozoa was 74.1% in BRSV-seropositive animals compared with 81.2% in seronegative bulls (n = 25) (p = 0.035). Field fertility was also slightly affected, the 60-day non-return rates were 75.2% and 76.8% for BRSV seropositive and seronegative bulls respectively (p = 0.014). Potential reasons for lowered sperm quality are discussed here.  相似文献   
74.

Background

Sex steroid hormone receptors have been identified in the adrenal gland of rat, sheep and rhesus monkey, indicating a direct effect of sex steroids on adrenal gland function.

Methods

In the present study, immunohistochemistry using two different mouse monoclonal antibodies was employed to determine the presence of oestrogen receptor alpha (ERalpha) and progesterone receptor (PR) in the mare adrenal gland. Adrenal glands from intact (n = 5) and ovariectomised (OVX) (n = 5) mares, as well as uterine tissue (n = 9), were collected after euthanasia. Three of the OVX mares were treated with a single intramuscular injection of oestradiol benzoate (2.5 mg) 18 – 22 hours prior to euthanasia and tissue collection (OVX+Oe). Uterine tissue was used as a positive control and showed positive staining for both ERalpha and PR.

Results

ERalpha staining was detected in the adrenal zona glomerulosa, fasciculata and reticularis of all mare groups. Ovariectomy increased cortical ERalpha staining intensity. In OVX mares and one intact mare, positive ERalpha staining was also detected in adrenal medullary cells. PR staining of weak intensity was present in a low proportion of cells in the zona fasciculata and reticularis of all mare groups. Weak PR staining was also found in a high proportion of adrenal medullary cells. In contrast to staining in the adrenal cortex, which was always located within the cell nuclei, medullary staining for both ERalpha and PR was observed only in the cell cytoplasm.

Conclusion

The present results show the presence of ERalpha in the adrenal cortex, indicating oestradiol may have a direct effect on mare adrenal function. However, further studies are needed to confirm the presence of PR as staining in the present study was only weak and/or minor. Also, any possible effect of oestradiol treatment on the levels of steroid receptors cannot be determined by the present study, as treatment time was of a too short duration.  相似文献   
75.
The relationship between bulk tank somatic cell count (SCC) and farm management and infrastructure was examined using data from 398 randomly selected, yet representative, Irish dairy farms where the basal diet is grazed grass. Median bulk tank SCC for the farms was 282,887 cells/ml ranging from 82,209 to 773,028 cells/ml. Two questionnaires were administered through face-to-face contact with each farmer. Herd-level factors associated with bulk tank SCC were determined using linear models with annual somatic cell score (i.e., arithmetic mean of the natural logarithm of bulk tank SCC) included as the dependent variable. All herd level factors were analysed individually in separate regression models, which included an adjustment for geographical location of the farm; a multiple regression model was subsequently developed. Management practices associated with low SCC included the use of dry cow therapy, participation in a milk recording scheme and the use of teat disinfection post-milking. There was an association between low SCC and an increased level of hygiene and frequency of cleaning of the holding yard, passageways and cubicles. Herd management factors associated with bulk tank SCC in Irish grazing herds are generally in agreement with most previous studies from confinement systems of milk production.  相似文献   
76.
The influence of interferon (IFN)-alpha on the in vitro differentiation of myeloid porcine dendritic cells (DC) was evaluated as the ability of the DC to stimulate to cell proliferation in a mixed leukocyte reaction (MLR), and as their ability to produce cytokines at exposure to bacterial and viral preparations. Porcine monocytes were enriched from purified peripheral blood mononuclear cells (PBMC) by plastic adherence and cultured in the presence of granulocyte-macrophage colony-stimulating factor (GM-CSF) and interleukin (IL)-4 or in GM-CSF, IL-4 and IFN-alpha. After 5 days of culture, the cells developed a dendritic morphology and the proportion of cells expressing MHC class II and B7 molecules was increased as determined by flow cytometry. Dendritic cells, differentiated for 5 days in GM-CSF, IL-4 and IFN-alpha, were able to stimulate both allogeneic and syngeneic PBMC to proliferation in an MLR. The DC produced the Th1 associated cytokines IFN-alpha at Sendai virus stimulation, and IL-12 at stimulation with plasmid DNA (pre-incubated in the presence of lipofectin), heat-inactivated Actinobacillus pleuropneumoniae, UV-inactivated Aujeszky's disease virus and live Sendai virus. The heat-inactivated bacteria and Sendai virus also induced production of the Th2 associated cytokines IL-10 and IL-6. The addition of IFN-alpha during differentiation of DC in GM-CSF and IL-4 enhanced their ability to stimulate allogeneic and syngeneic MLR, but did not alter their ability to produce cytokines.  相似文献   
77.
The aim of this investigation was to examine the chromatin configuration of the nucleus, pattern of mitochondrial aggregation and mitochondrial activity in parallel studies in the same horse oocytes. Horse oocytes recovered by ultrasound-guided follicle aspiration in vivo were classified according to two main initial cumulus morphologies as having compact or expanded cumulus. The percentage of oocytes with a diplotene meiotic configuration at the time of recovery from the follicles was highest in compact oocytes. Oocytes with expanded cumulus layers at the time of recovery matured more rapidly in vitro and reached a proportion >50% at the metaphase II stage (M 2) sooner during in vitro maturation (IVM), than did compact oocytes. The mitochondrial aggregation pattern changed from finely distributed (Type 1) through crystalline (Type 2) to an aggregated, granulated appearance (Type 3) during IVM. The pattern of mitochondrial aggregation at the time of recovery was associated with the initial cumulus morphology of the oocyte, in that compact oocytes had a higher proportion of Type 1 aggregation, whereas expanded oocytes had a higher proportion of Type 3. The fluorescence intensity of metabolic active mitochondria, measured by fluorescence intensity (Em 570) per oocyte after MitoTracker CMTM Ros orange labelling, increased in the oocytes during IVM and depended on initial cumulus investment. Oocytes with the granulated type of aggregated mitochondria Type 3 had the highest level of metabolic activity and were in more progressed stages of meiosis (A 1-M 2). Oocytes initially having expanded layers of cumulus reached significantly higher levels of mitochondrial activity after IVM than did oocytes initially having compact cumuli. During resumption of meiosis the mitochondrial activity of oocytes with initially expanded cumulus increased continuously up to M 2, whereas in oocytes from compact cumulus-oocyte complex (COC), the activity declined after A 1/T 1 stages of meiosis.  相似文献   
78.
SUMMARY Clinical, diagnostic and biochemical features of generalised glycogenosis are described In 96 Brahman-type calves. Typically the calves were presented when about 6 months of age, with III-thrift and muscular weakness as the most common signs. Acidic α-glucosidase activity was reduced in peripheral blood lymphocytes and skeletal muscle. Muscle glycogen concentration was consistently higher in affected animals than In clinically normal cattle. Other observations in affected calves Included elevation of serum aspartate amlnotransferase and creatine kinase activities and excessive amounts of high molecular weight oligosaccharides in urine. Fine cytoplasmic vacuolation of neurones In the brain and spinal cord, skeletal muscle, myocardlum and of Purkinje fibres were consistent histological observations. Periodic acid-Schlff staining revealed the presence of glycogen-like material In peripheral blood lymphocytes of all affected calves, Indicating that this is a useful aid for the diagnosis of glycogenosis. While 3 of the 96 calves showed somewhat different clinical signs, the similarity of pathology and the biochemical and clinical evidence in the remainder suggested that, In these animals, the disease was expressed as a single syndrome.  相似文献   
79.
80.
Contents: Prolactin (PRL) was isolated from human amniotic fluid and than fractionated on Concanavalin A-Sepharose (ConA-S). Two fractions were tested for the 3H-thymidine incorporation in the DNA of bovine granulosa, oviductal and stromal cells as well as splenocytes. All cell types reacted to PRL I or PRL II in a dose dependent manner. In general the effect of PRL I was greater than PRL II, and low concentrations of both enhanced the cell proliferation more than higher doses. The incorporating effect of 3H-thymidine under the influence of PRL I was higher in stromal cells and splenocytes than in granulosa and oviductal cells. PRL II did not have such a stimulating effect, even the presence of 14 ng/ml resulted in a decrease of 3H-thymidine incorporation in granulosa cells. The reason of this different intensity of tested PRL variants may depend on the molecular heterogeneity. The results indicate that PRL forms possess a cel type-specific effect on the proliferation of cells of the bovine female reproductive tract and splenocytes.  相似文献   
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