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1.
In the submitted work we concentrated our attention on the study of the changes in neurosecretion. PAS positive mucopolysaccharides in the hypothalamus and ependyma of the IIIrd cerebral ventricle and on studying the changes in the volume of the cell nuclei of the neurons of nucl. supraopticus (NSO), nucl. hypothalamicus centromedialis (NVM) and nucl. tuberomamillaris (NTM) of sheep after irradiation and after hormonal stimulation. We made our observations on 28 sheep of the Slovak Merino breed, of average live weight 35 to 40 kg, two- and three-years old in the period of physiological anoestrum. The first group of four ewes and the second group of four yearling lambs were controls. The third group of six ewes and the fourth group of six yearlings were exposed to irradiation all over with a dosage of 2.46 Gy (250 R) for a period of five days. To synchronize the oestrum of all the sheep we used agelline sponges which we fitted five days before irradiation. After the irradiation and removal of the sponges we gave the test sheep hormonal stimulation with 3 X 500 i. u. of serum gonadotropin. The fifth group of four ewes and the sixth group of four yearlings were only stimulated without irradiation. The fifth day after stimulation we slaughtered the sheep. We processed the brain samples by the usual histological methods. We carried out karyometric analysis with 3000X magnification and the measurement of 200 cells from one sample. We processed the values obtained mathematically according to Fischer and Inke (1956). We evaluated the quantity of neurosecretion material with a light microscope according to Nakahara (1962). We found that the multiplication of neurosecretion and the increased activity of the PAS reaction in the hypothalamic nuclei studied show that the irradiation and hormonal treatment stimulate the function of the hypothalamic structures. The results of the karyometric analysis in the yearlings also confirm this opinion. In the ewes the inhibitive influence of irradiation was probably manifest. The giving of hormones in combination with irradiation causes the multiplication of ependyma cells and the desquamation of surface layers.  相似文献   

2.
The effect of the exposure of the whole body to continuous radiation and of the administration of serum gonadotropin (SG) was studied as exerted on the concentration of catecholamines (epinephrine and norepinephrine) in the hypothalamus, epiphysis and adrenal glands of ewes during the anoestric period with synchronized oestrus. The first group (young barren ewes) and second group (older ewes) were exposed to continuous radiation of 60Co for five days. The radiation was provided at the rate of 0.020 Gy per hour. After the termination of irradiation the ewes were subjected to hormonal stimulation by fractionated administration of 1500 I. U. SG. The third and fourth experimental groups of ewes were stimulated with 1500 I. U. SG without irradiation. Catecholamines were separated from the tissue supernatants by the adsorption chromatographic method and the catecholamine contents in the eluates were determined spectrofluorometrically. Protracted exposure to gamma radiation and hormonal stimulation with SG reduces the concentration of norepinephrine in the whole hypothalamus of the sheep. A statistically significant decrease (P less than 0.001) was recorded in the medial and caudal hypothalamus of the adult ewes and in the rostral and caudal hypothalamus regions of the young ewes. A decrease of norepinephrine concentration, statistically significant in the caudal (P less than 0.01) and medial hypothalamus, was recorded in the group of adult ewes after hormonal stimulation with SG without irradiation. The experimental group of young ewes responds to hormonal stimulation by a greater reduction of norepinephrine contents, as compared with combined exposure to radiation and hormonal stimulation. It is assumed that the decrease in catecholamine concentration after hormonal stimulation with SG is associated with the increase in the content of oestrogens, which act on the adrenergic receptors of the hypothalamus.  相似文献   

3.
By means of histological methods of histochemical nature we examined the qualitative alterations in neurosecretory cells of anterior (nucl. paraventricularis - NPV. nucl. preopticus medialis - NPM), medial (nucl. arcuatus s. infundibularis - NARC), and posterior (nucl. tuberomamillaris - NTM) hypothalamus of sheep with a simultaneous caryometric analysis of neurons of the same nuclei after administration of various PMSG doses. The examination was performed on the brain samples of 23 two- to three-year-old sheep, of the Slovak Merino breed, at the live weight of 30 to 40 kg. in the period of physiological anoestrus (June-July). The animals were divided into three experimental groups and were instilled agellin sponges (20 mg). On the 13th day the sponges were removed and the first group was applied 1000 i. u. PMSG, the second group 750 i. u. PMSG. The sheep were killed within 30 to 36 hours after the oestrus determination with a teaser ram. After bleeding of animals the brains were perfused with 2% buffered paraformaldehyde and after taking out the brains from the crania their fixation was finished in buffered picroformol. Paraffin slices were stained with haematoxylin-eosine and crotonaldehyde-fuchsin to neurosecretions. Caryometric analysis was carried out with a 1000 fold magnifying and with a measuring of 200 cells from one sample. We recorded the neurosecretion increase in all hypothalamic nuclei under study. The caryometric analysis has shown a moderate shift to the right, it means the volume increase of nuclei of neurosecretory cells, which demonstrates a stimulation of the function of hypothalamic structures.  相似文献   

4.
The effect of exogenous hormonal preparations (PMSG, SG, PMSG + PGF2 alpha and FSH) was studied as exerted on neurosecretion and on changes in the nuclear volume of nucleus paraventricularis, nucleus ventromedialis, nucleus infundibularis and nucleus tuberomamillaris, and on histological changes in the third cerebral ventricle. Changes in catecholamine concentrations were determined in the rostral, medial, and caudal hypothalamus of the ewes. The study was performed with 28 ewes of the Slovak Merino breed during the oestrus period. The oestrus was synchronized by the Agelín vaginal tampons (Spofa). The ewes of four experimental groups were stimulated by the administration of 1000 I.U. PMSG (Antex-Leo), 1000 I. U. Serum Gonadotropin (Bioveta Ivanovice na Hané), 1000 I. U. PMSG with 250 micrograms Oestrophan inj. (Léciva Praha), and 450 I. U. Folistiman (VEB Arzneimittelwerk Dresden, GDR). The brain samples were processed by common histological methods. A caryometric analysis was performed at 3000-fold magnification and by measurement of 200 cells of one sample. The data were subjected to mathematical processing after Fischer and Inke (1956). The amount of neurosecretory material was evaluated by light microscopy (Nakahara, 1963). The multiplication of neurosecretion in the hypothalamic nuclei testifies to the fact that the administration of hormonal preparations stimulates the function of hypothalamic structures, which corresponds with the results of the caryometric analysis. It also ensues from the results that the administration of serum gonadotropins (PMSG and SG) at the dose of 1000 I. U. results in a statistically significant decline (P less than 0.001) of the concentrations of norepinephrine in the rostral, medial and caudal hypothalami of the ewes, although the PMSG preparation has a more pronounced effect when compared with SG. The hormonal stimulation with PGF2 alpha and with FSH causes no significant changes in the concentration of norepinephrine in the hypothalamus of the ewes. As norepinephrine is considered as a neurosecretion inhibitor, the multiplication of neurosecretion in the hypothalamus nuclei after stimulation with serum gonadotropins correlates with the decline of hypothalamic norepinephrine concentrations.  相似文献   

5.
The changes were studied in the levels of catecholamines and L-DOPA in the control system of reproduction cycle (hypothalamus, hypophysis) and in adrenal glands of sheep after all-body irradiation with 60Co at the total dose of 6.7 Gy for seven days. The power input per hour of irradiation source was 0.039 Gy. The catecholamines (noradrenaline, dopamine and adrenaline) and L-DOPA were determined, after having been isolated from the tissues, by the method of spectral fluorimetry. After all-body exposition to gamma-radiation noradrenaline dropped in hypothalamus in comparison with the control group of sheep, most significantly in the rostral (by 74.2%) and caudal part (by 40%). A similar drop like in the case of noradrenaline was also observed in dopamine, the concentrations of which decreased in rostral hypothalamus by 72%, in medial hypothalamus by 94% and in caudal hypothalamus by 60%. Adrenaline shows a drop in hypothalamus, most significant in caudal region (by 62%). In relation with that the level of a precursor for the synthesis of catecholamines and L-DOPA has been changed which achieved, in the studied regions of hypothalamus in sheep, significantly lower levels than were determined in the control group of sheep. As regards the hypophysis, after irradiation no significant changes in the levels of noradrenaline and adrenaline were recorded, however, dopamine and L-DOPA dropped significantly (P less than 0.01). The exposition to gamma-radiation also causes a decrease in the concentrations of catecholamines and L-DOPA in the adrenal glands of sheep, most significant in noradrenaline (by 61%).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

6.
The effects were investigated of a hormonal preparation of serum gonadotrophin (SC) on neurosecretion, PAS-positive mucopolysaccharides and on histological changes in the third cerebral ventricle; at the same time variations were determined of catecholamine concentrations of ependyma surface in the hypothalamic regions that control directly reproductive functions in ewes of the Merino and Wallachian breeds in the oestrus period. Ewe oestrus was synchronized by insertion of Ageline (Spofa) sponges into the vagina. A dose of 2000 IU of serum gonadotrophin (Bioveta, Ivanovice in Haná) was administered to stimulate the ewes (n = 30). Twelve ewes of the Wallachian breed, six control and six test ones, were used for radioenzymatic detection of catecholamines (Catechola test, Prague). The brains were segmented immediately after bleeding and samples were taken from the eminentia medialis, area preoptica and corpus mamillare pursuant to the stereotactic configuration of the sheep hypothalamus (Welento et al., 1968). The brains of ten ewes of the Merino breed, four control and six test ones, and of eight ewes of the Wallachian breed (four control and four test ones) were used for histological treatment. For the purposes of a histological study, the brains were treated with current histological methods. The amount of neurosecretory material was assessed by light microscopy (Nakahara, 1963). Samples for the study of ependyma of the lower part of the third cerebral ventricle were examined in a scanning electron microscope. The obtained results demonstrate a statistically significant decrease by 36.4% (P less than 0.05) in epinephrin concentrations in the area preoptica of hypothalamus after SG administration (Fig. 3), in comparison with the control group. A decrease in norepinephrin concentration in the corpus mamillare (Fig. 4) was statistically significant (P less than 0.001). The dose of 2000 IU SG influenced most markedly catecholamine concentrations in the eminentia medialis (Fig. 5), where a statistically significant decrease in epinephrin and norepinephrin concentration was observed (P less than 0.01). Dopamine concentrations also decreased significantly (P less than 0.05) in the eminentia medialis (Fig. 5). Following the hormonal stimulation, a significant increase in dopamine and epinephrin concentrations was observed in the hypophysis of sheep (Fig. 6; P less than 0.05) and in the epiphysis there was a significant decrease in epinephrin and dopamine concentration (P less than 0.01).(ABSTRACT TRUNCATED AT 400 WORDS)  相似文献   

7.
Concentrations of histamine were quantified by an enzymatic isotopic assay in different regions of the brain and pituitary gland of gonadal-intact and chronically ovariectomized ewes during the anestrous season. Sera concentrations of LH were confirmed to be elevated in ovariectomized compared with intact animals immediately before tissues were obtained. Areas of the brain that were examined included cerebral cortex, thalamus, pineal gland, hypothalamus (rostral, medial basal, median eminence), midbrain, cerebellum and brain stem. Concentrations of histamine were greatest within the thalamus, pineal gland, medial basal hypothalamus and median eminence. Histamine within the medial basal hypothalamus was greater (P less than .05) in ovariectomized than in ovarian-intact animals. Further experiments were designed to determine the effect of antihistaminic drugs on secretion of LH. Ovariectomized ewes were treated every 6 h (i.m.) for 24 h with diphenhydramine (an antagonist of the H1-receptor for histamine), cimetidine (an H2-receptor antagonist), a combination of the drugs, or vehicle. Twelve hours after initiation of treatments, animals were injected with estradiol. Diphenhydramine depressed (P less than .01) basal serum concentrations of LH and the positive feedback effect of estradiol on serum concentrations of LH. Cimetidine did not influence the pattern of secretion of LH. Diphenhydramine did not alter LHRH-induced release of LH in ovariectomized ewes or basal serum concentrations of LH in ovarian-intact anestrous ewes. We suggest that histamine acts at the level of the central nervous system through an H1-receptor mechanism to control secretion of LH in female sheep.  相似文献   

8.
Caryometric analysis was used for the study of changes in the cell nucleus volume of the neurons of nucleus paraventricularis, nucleus arcuatus, and ependyma of the third cerebral ventricle of sheep after the administration of Gn-RH, followed by exposure to X-rays. The test animals were 12 ewes in physiological anoestrus and two rams. The trials were conducted in spring. The first group of four sheep and two rams were left as controls; in the ewes of the second group the hypothalamo-hypophysial region was irradiated by exposure to 516.5 mC/kg (200 R); in the four ewes of the third group, ovaries were directly irradiated at laparotomy by exposure to 64.4 mC/kg (250 R). The ewes of the second and third group were treated with an i. m. administration of 400 micrograms Gn-RH per head before irradiation. The excisions were collected and processed the tenth day from irradiation. The studied material was fixed by injection of 10% formalin and finished by another dose of 10% formalin after the excision of the brains. The paraffin slices were stained with haematoxylin-eosine. The caryometric analysis was performed at 3000-fold magnification, 200 cells being measured in each sample. Changes in neurosecretory cells were described in the regions of nucleus paraventricularis, nucleus arcuatus and in the ependyma of the third cerebral ventricle. The results of the caryometric analysis of nucleus paraventricularis and nucleus arcuatus suggest that the administration of Gn-RH and irradiation of the hypothalamo-hypophysial region, and direct irradiation of ovaries, stimulate the studied cerebral structures. The changes observed in the ependyma of the third cerebral ventricle after the administration of Gn-RH and subsequent irradiation of the hypothalamo-hypophysial region are insignificant; it is only after the direct irradiation of ovaries that these cells are inhibited by an indirect effect through the feedback mechanism.  相似文献   

9.
The pattern of changes in the trypsin-inhibition activities (TIA) of blood plasma, cervical mucus and in the morphological structure of cervix was studied in ewes exposed to 60Co radiation for seven and five days, the radiation doses being 6.7 Gy and 4.8 Gy (700 and 500 R). During exposure, the group of ewes irradiated with 4.8 Gy was given the Roboran vitamin premix in addition to standard feed. After termination of irradiation the animals in this trial were given the ampicillin antibiotic (5250 mg). TIA was determined from the retardation of the hydrolysis of the synthetic substrate N-alpha-tosyl-p-nitroanilide (TAPA) by bovine trypsin; the TIA was expressed as the percentage of inhibited trypsin. As found on the day of the termination of irradiation, almost all the studied TIA values of blood plasma and cervical mucus were increased in the irradiated animals, the range being from 103.1 to 155.0% of the levels for non-irradiated ewes. A reduction was recorded only in total TIA of blood plasma in the group irradiated with the dose of 6.7 Gy (83.1% of the values for non-irradiated animals). In the group of animals irradiated with 4.8 Gy and fed no Roboran, the TIA of cervical mucus was observed to decrease to 92.4%. When evaluating the average TIA of different test groups throughout the experiment it was found that all the studied TIA values of the irradiated animals increased within a range from 104.1 to 184.0% of the values for untreated ewes. It was only in the average values of total TIA in blood plasma that, after irradiation with 6.7 Gy, a decrease to 92.7% of the level without irradiation was recorded. It was found during the study of changes in the proportions of glands in the stroma and changes in epithelium thickness in the mucous membrane of cervix uteri that the irradiated ewes had the epithelium thickness reduced to 95.3%-65.5% and that their stromal gland number decreased to 75.4%-79.7% of that recorded in non-irradiated animals. It was only in the group given a Roboran supplement that an increase to 123.7% of the gland number for untreated ewes was recorded on the tenth day after the termination of irradiation.  相似文献   

10.
A study was performed on the distribution of catecholamines (noradrenaline, dopamine and adrenaline) and L-DOPA in the hypothalamo-hypophysial region, as well as in the region of n. caudatus, which participate in the control of sexual activities in sheep. After isolation in the activated aluminium oxide, the catecholamine concentration was determined spectrophotometrically. Hypothalamus was divided into three regions: rostral, medial and caudal. In the same regions of the cerebroneural system (CNS), the activity of the degradation enzyme monoaminooxidase (MAO) was determined by radiochemical method. 14C-tryptamine was as a substrate and the results were measured by means of scintillation spectrophotometer Packard. The distribution of catecholamines and L-DOPA in the hypothalamus of sheep is different. The largest proportion is that of noradrenaline in caudal hypothalamus (1.84 +/- +/- 0.36). The dopamine levels in hypothalamus are quite balanced though substantially lower than those of noradrenaline (from 0.22 to 0.31 micrograms/g). The concentrations of adrenaline and L-DOPA in the sheep hypothalamus are low. The sheep hypophysis contains more noradrenaline (1.70 +/- 0.38), adrenaline content amounts to 1.30 +/- 0.28. L-DOPA and dopamine occur in this region at low concentrations. In comparison with the other regions of sheep brain, high dopamine concentrations (2.0 +/- 0.58 micrograms/g) and higher L-DOPA levels were determined in n. caudatus. The activity of the degradation enzyme monoaminooxidase in the cerebroneural system of sheep is different. The highest MAO activity was determined in the rostral hypothalamus (1100 pmol X mg-1 X min-1), lower in its caudal and medial region.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

11.
The changes in volume, weight and the histomorphological changes of the tertiary follicles of ewes were studied after protracted irradiation with 4.8 Gy in the anoestrous period by the morphometric and qualitative histological methods. The trial was performed in May with 21 ewes of the Slovak Merino breed, divided into three groups. The first group (five ewes) was control. The second and third groups (each containing eight ewes) were exposed to gamma-rays for five days, the total dose being 4.8 Gy. Within ten days after the treatment, all the irradiated and control ewes were given Ampicillin Spofa per os at a dose of 250 mg per head/day and Roboran Spofa at a dose of 10 g per head/day. The animals were killed by bleeding on the fifth day of irradiation and on the tenth day after the end of the treatment. After killing, the volume and weight of the ovaries were determined and a common histological method was used to cut these ovaries into 7 microns slices in series 70 microns apart. The slices were stained with haematoxylin-eosine and were evaluated by means of light microscopy. After irradiation the weight of the ovaries was found to decrease significantly; however, ovary volume remained unchanged. The atretic and non-atretic tertiary follicles were subjected to qualitative histological differentiation after Marion et al. (1968) and the number of non-atretic follicles was found to have decreased significantly in the irradiated ewes. The late type of atresia contributes most significantly to an increase in the proportion of atretic tertiary follicles. The administration of vitamins after irradiation reduced the occurrence of atretic changes.  相似文献   

12.
The main purpose of the study was to investigate whether the feeding system applied has any effect on the status of blood selenium (Se) and vitamins A and E in dairy sheep. In total 200 dairy sheep from 10 flocks were used in the study (20 animals per flock). Group A consisted of 100 sheep (five flocks) reared under the intensive feeding system and group B of 100 sheep (five flocks) reared under the semi-intensive feeding system. The 100 sheep of each group consisted of 25 lambs aged 3-6 months, 25 ewes 1-3 years, 25 ewes more than 3 years and 25 non-lactating ewes in late gestation. Another purpose was to evaluate the potential effect of the age and the reproductive stage of the animals on these parameters. To determine the effect of age, 150 of these animals were divided into three subgroups: 50 lambs, 50 non-pregnant lactating ewes aged 1-3 years and 50 non-pregnant lactating ewes aged more than 3 years. For the evaluation of the effect of the reproductive stage the 50 non-lactating ewes in late gestation and the 100 non-pregnant lactating ewes were used. Blood samplings were performed once, between December and January for non-lactating ewes in late gestation and March to May for lambs and lactating ewes. Whole blood Se and vitamin E and A serum concentrations were determined. The main conclusion is that the feeding system significantly affects Se and serum vitamin A concentration, as they were higher in the intensive one. It was secondly concluded that age affects the serum concentrations of vitamin A.  相似文献   

13.
The study was aimed to research the effects of Oxytropis glabra DC (O.glabra DC) poisoning on reproductive organs coefficent, reproductive performance and related gene expression in Hetian sheep ewes. The sera, hypothalamus, pituitary and ovary of Hetian sheep ewes cases poisoning of O. glabra DC were collected, the organ exponent and contents of GnRH, FSH, LH, E2 and P4 in serum were measured, then the mRNA expression of reproductive genes were measured. The result demonstrated that the index of hypothalamus, pituitary and ovary were extremely significantly higher than normal sheep (P < 0.01),the follicle number on the surface of the ovaries in poisoning groups were significantly lower than normal sheep (P < 0.05). The result of hematoxylin-eosin staining showed that the nuclear of neuronal cells in hypothalamus were pyknosis and hyperchromatic; The nuclear of cells in pituitary deformation and hyperchromatic, cytoplasm decreased; The primary oocyte in ovary dissolved, disappeared, interstitial blood vessel expanded. The content of GnRH, FSH, LH, E2 and P4 in serum in poisoned Hetian sheep ewes were extremely significantly lower than normal sheep (P < 0.01). The mRNA expression levels of Kiss-1, GPR54, ERα in hypothalamus, GnRHR in pituitary and FSHR and LHR in ovary were extremely significantly lower than normal sheep (P < 0.01). The result showed that O. glabra DC poisoning could affect Hetian sheep ewes reproductive system by affecting microstructure and ultrastructure of hypothalamus-pituitary-ovarian axis.  相似文献   

14.
试验旨在探讨小花棘豆(Oxytropis glabra DC)中毒对和田羊母羊繁殖器官指数、性激素水平和相关基因mRNA表达量的影响。以小花棘豆中毒和田羊母羊为研究对象,采集血清后屠宰,采集试验羊的丘脑、垂体和卵巢组织,测定其脏器系数,检测血清中促性腺激素释放激素(GnRH)、促卵泡素(FSH)、促黄体素(LH)、雌二醇(E2)和孕酮(P4)含量的变化,并检测各组织中相关繁殖基因的表达。结果显示,小花棘豆中毒和田羊母羊丘脑、垂体和卵巢指数均极显著升高(P < 0.01),且卵巢表面卵泡数显著下降(P < 0.05),HE染色表明丘脑神经元细胞固缩、浓染;垂体中细胞核变形、浓染,胞浆减少;卵巢中初级卵母细胞溶解、消失,间质血管扩张。小花棘豆中毒和田羊母羊血清中GnRH、FSH、LH、E2和P4含量均极显著下降(P < 0.01),丘脑中Kiss-1、GPR54、ERα mRNA,垂体中GnRHR mRNA和卵巢中FSHR、LHR mRNA表达量均极显著下降(P < 0.01)。结果表明,小花棘豆毒性成分可通过丘脑-垂体-性腺轴影响和田羊母羊的生殖系统。  相似文献   

15.
Maedi-Visna is a lentiviral disease of sheep with a worldwide distribution. The transmission of the virus occurs primarily via colostrum and milk from the infected ewe to its newborn lamb but also horizontally between sheep. The most obvious clinical symptoms are progressive dyspnea and emaciation. In this prospective study an eradication based on serological testing and removing of seropositive animals was performed in 24 flocks of sheep of the breed "Walliser Schwarznasenschafe" leading to a reduction of the seroprevalence from 36% to 1% within two years. The control group consisted of 21 flocks of sheep. Lambs of seropositive ewes had a 7.6 times higher risk to seroconvert within their first two years of life compared to those of seronegative ewes. The dynamics of the spread of the infection were studied in birth cohort groups. Cohort animals of seropositive ewes showed an obvious trend to seroconvert slowly. Seropositive ewes had a significantly lower reproduction rate and their lambs suffered from significantly higher death and lower growth rates, probably due to a reduced milk production, resulting in economic losses.  相似文献   

16.
Various cell cultures were evaluated for their ability to support progressive pneumonia virus infection in vitro. Ovine trachea cells supported progressive pneumonia virus infection for an extended time,were extremely durable and could be passaged up until 30 passages. Progressive pneumonia virus infected ovine trachea cells were then used for the production of antigen for agar-gel immunodiffusion. A method for concentrating antigen, diafiltration, was compared to dialysis against polyethylene glycol. Using diafiltration, the concentrated virus was easily quantitated, less viscous (and therefore easier to apply) and only produced one precipitation line. Agar-gel immunodiffusion was used to survey 401 animals from two sheep flocks. One flock (96 sheep) was free of progressive pneumonia while the other flock had 111 of 305 total animals positive for precipitating antibodies. The incidence of precipitating antibodies in sheep ranged from 23% for yearling ewes to 80% in ewes seven years old.  相似文献   

17.
The aim of the present study was to determine the normal ranges of the most commonly used serum biochemical parameters of sheep reared under Greek breeding conditions, as well as to test for the effects of the age and reproductive status of the animals on the normal values of these parameters. In total, 200 clinically healthy Chios sheep from 10 farms were used in the experiment. For the determination of the effect of age 150 sheep were assigned in three groups. Group A consisting of 50 lambs aged 2-6 months (mean +/- SD: 4.15 +/- 1.08), group B of 50 non-pregnant ewes into lactation aged 1-3 years (mean +/- SD: 2.12 +/- 0.86) and group C of 50 non-pregnant ewes into lactation aged more than 3 years (mean +/- SD: 5.98 +/- 1.66). For evaluating the effect of reproductive status 50 pregnant ewes in dry period were used, 15-30 days before the expected day of lambing (group D), along with the 100 non-pregnant ewes into lactation of groups B and C (group E). Blood sampling was performed once, in dry ewes from December to January, and in lambs and lactating ewes from March to May. The results showed that of the 14 biochemical parameters determined in serum, six were significantly affected by the age and eight by the reproductive stage of the animals.  相似文献   

18.
Gradually increased radiation doses were applied directly to the ovaries of laparotomized ewes. The effect of these doses was studied as exerted on the qualitative and quantitative changes in the follicular apparatus of the ovaries and adenohypophysis of ewes in anoestrus and upon the recovery processes later on after irradiation. The ovaries irradiated with the dose of 4.79 Gy were found to be heavier when examined after some time from irradiation. The 10th and 30th day from irradiation the number of tertiary follicles decreased, the 100th day from irradiation their number increased to a four-fold level, as compared with the 10th day. Adenohypophysis showed a gradual growth of the number of PAS-positive cells. After the irradiation of ovaries with the dose of 9.57 Gy the ovaries showed the lowest rate of damage on the 10th day from irradiation; the 30th and 100th day from irradiation all the present tertiary follicles were in the state of atresia. In comparison with the control group, the amount of gonadotropic cells of adenohypophysis gradually increased, recovering from a rapid drop after irradiation. When the ovaries were irradiated with the dose of 19.14 Gy, all the tertiary follicles were in the state of atresia and the number of PAS-positive cells of adenohypophysis was lower in comparison with the control group.  相似文献   

19.
Abnormalities of the reproductive tract of female sheep were studied by examining 9970 reproductive tracts from cull ewes and 23,536 tracts from nulliparous sheep (prime lambs) over a period of 12 months in abattoirs in south-west England. Overall, 3.37 per cent of the tracts were pregnant (8.11 per cent of cull ewes, and 1.36 per cent of nulliparous sheep), with a peak incidence between September and December. A total of 655 ewes (6.57 per cent) and 459 nulliparous sheep (1.95 per cent) had acquired abnormalities of the reproductive tract. Within these totals, abnormalities of the ovaries accounted for 3.51 per cent (for the ewes) and 10.68 per cent (for the nulliparous sheep) of all the abnormalities, and abnormalities of the ovarian bursa and uterine tube accounted for 42.1 per cent (for the ewes) and 5.23 per cent (for the nulliparous sheep). In addition, uterine lesions (hydrometra and metritis) accounted for 9.92 per cent (for the ewes) and 13.51 per cent (for the nulliparous sheep); lesions of the cervix and vagina (total of 1.44 per cent) and Cysticercus tenuicollis cysts associated with the reproductive tract (total of 3.05 per cent) were less common. Among the ewes the most common ovarian lesions were ovulation tags, and follicular cysts were the most common in nulliparous animals. Lesions such as bursitis, parametritis and abscesses of the reproductive tract were much more common in cull ewes than in nulliparous sheep, probably having arisen from peripartum infections. Hydrosalpinx and hydrometra, in which the intraluminal fluid was clear, were present at relatively high incidence in nulliparous animals, but not in cull ewes. The proportion of tracts containing macerated fetal remnants (2.14 per cent of all abnormalities in cull ewes) was lower than expected. It was considered that the functional significance of many of the lesions, such as ovulation tags and C tenuicollis cysts, was likely to be low, although in some cases of the latter calcification of the cyst had occluded the uterine tubes. Other lesions, notably hydrosalpinx, bursitis and metritis were likely to have made the affected animals sterile. The acquired abnormalities were therefore more significant in terms of individual animal infertility than as a major cause of infertility in flocks.  相似文献   

20.
Scrapie is a naturally occurring transmissible encephalopathy of sheep and goats. Currently available methods for diagnosis are the presence of characteristic histopathologic changes and detection of an abnormal form of prion protein (PrPres) in the brains of affected animals. This study documents preclinical and subclinical scrapie in a flock of 16 sheep utilizing histopathology, immunohistochemistry (IHC), western blot, and electron microscopy (for scrapie-associated fibrils) for confirmation of the disease. Prior to necropsy, none of the sheep showed signs of clinical scrapie. Based on the results of histopathology and positive PrPres tests, 3 ewes were found to have subclinical scrapie. An additional ewe, which did not have histopathologic changes in the brain but was positive by IHC and western blot,was considered a preclinical case of scrapie. None of the sheep had amyloid in the brain stem.  相似文献   

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