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晚春蚕种生产在全年生产上有其独特的优势,缓解春秋两季生产的压力,充分利用原蚕基地、生产用具、制种劳力。介绍了原蚕区晚春制种生产成绩,探讨了关键性生产技术和生产要求,总结并提出了晚春蚕种生产布局的合理性与可行性。 相似文献
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胚胎移植(embryo transfer)技术作为提高动物繁殖能力的有效手段,在奶牛生产上已得到广泛应用,并且有广阔的发展前景,随着胚胎移植产业化的发展,胚胎移植技术(以下简称ET技术)在奶牛生产上显著的繁育效果和良好的经济效益将会日渐表现出来,同时,胚胎移植技术在奶牛生产上的应用存在的问题也应该引起足够的重视,本文着重讨论了胚胎移植技术在奶牛生产育种、繁殖和饲养管理等方面的具体应用. 相似文献
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低聚果糖的生产工艺及应用 总被引：1，自引：0，他引：1
时晓丽 《养殖与饲料．饲料世界》2010,(5):45-48
介绍了低聚果糖的理化特性,概述了其在动物生产、饲料、疾病防治等方面的作用,着重阐述了其不同生产方法的工艺特点,并展望低聚果糖在畜牧生产上的应用前景。 相似文献
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Plasma concentration profiles of gonadotrophins and testosterone in the adult boar. 总被引：1，自引：1，他引：0 
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下载免费PDF全文 Follicle stimulating hormone, luteinizing hormone and testosterone were measured by radioimmunoassay in plasma samples collected at 15 min intervals for a 12 h period in eight adult boars. Pulse increases in follicle stimulating hormone concentrations varied from one to four between individual boars while those of luteinizing hormone ranged from zero to four. The index of hormone production, provided by calculation of the area under the curve, was 0.5 +/- 0.51 microgram/L (means +/- S.D.) for follicle stimulating hormone and 0.46 +/- 0.11 microgram/L (means +/- S.D.) for luteinizing hormone. A significant correlation between changes in follicle stimulating hormone and luteinizing hormone values was seen in only two boars. The mean plasma testosterone concentration was 7.43 +/- 1.58 nM/L (means +/- S.D.). An identified increase in testosterone values occurred once in the 12 h period for six of the boars but was not noted in the other two animals. Although increases in testosterone could be identified with a previous pulse of luteinizing hormone, not all luteinizing hormone pulses were followed by an elevation in testosterone. A significant correlation between luteinizing hormone and testosterone was present in three of the eight animals. Follicle stimulating hormone and luteinizing hormone were measured in samples similarly collected two weeks after castration in the same eight boars. The number of pulses of follicle stimulating hormone increased significantly (p less than 0.05) and ranged from 3 to 7/12 h. The index of production of 1.8 +/- 1.15 micrograms/L (mean +/- S.D.) also represented a significant increase (p less than 0.05) over precastration follicle stimulating hormone values.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Our goal was to identify the cells expressing Pit-1 protein in chicken anterior pituitary. The anterior pituitaries were collected from laying hens after perfusion with formalin-PBS, and fixed with Bouin's fixative followed by paraffin embedding. Sections of the anterior pituitaries were immunostained for Pit-1 in the first staining sequence followed by staining for 6 types of pituitary hormones in the second sequence. Pit-1 positive nuclei were observed in the glandular cells in both the cephalic and caudal lobes. Pit-1 immunoreaction products were colocalized in the glandular cells immunopositive for growth hormone, thyroid-stimulating hormone, follicle-stimulating hormone, luteinizing hormone, adrenocorticotropic hormone or prolactin. These results indicate that Pit-1 protein induction occurs in 6 types of glandular cells, suggesting that Pit-1 may regulate hormone synthesis in each glandular cell in the chicken pituitary. 相似文献
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Shiro KUSHIBIKI Hiroyuki SHINGU Tokushi KOMATSU Fumiaki ITOH Etsuko KASUYA Hisashi ASO Koichi HODATE 《Animal Science Journal》2006,77(6):603-612
Tumor necrosis factor (TNF)‐α is a powerful macrophage cytokine released during infection, circulating in the blood to produce diverse effects in the organism. We examined the effect of recombinant bovine TNF‐α (rbTNF‐α) administration on hormone release in dairy cows during early lactation. Twelve non‐pregnant Holstein cows were treated subcutaneously with rbTNF‐α (2.5 µg/kg) or saline twice (at 11.00 and 23.00 hours). At 11.00 hours the next day, the cows were given growth hormone‐releasing hormone (GHRH, 0.25 µg/kg), thyrotrophin‐releasing hormone (TRH, 1.0 µg/kg), thyroid‐stimulating hormone (TSH, 10 µg/kg) or adrenocorticotropic hormone (500 µg/head) via the jugular vein. In the growth hormone‐releasing hormone challenge, the plasma growth hormone concentration was lower in the rbTNF‐α group than in the control (saline) group. The growth hormone and TSH responses to TRH were also smaller in the rbTNF‐α group than in the control. The plasma prolactin response to TRH was not affected by the rbTNF‐α treatment. In the TSH challenge, the rbTNF‐α‐treated cows had lower responses, as measured by plasma triiodothyronine and thyroxine, than the control cows. The rbTNF‐α treatment produced an increase in the basal plasma cortisol level, but the cortisol response to adrenocorticotropic hormone was the same level in both groups. The plasma concentrations of TNF‐α and interleukin‐1β in the cows were elevated by the rbTNF‐α treatment. The milk yield was reduced by the rbTNF‐α administration during 4 days. These data demonstrate that TNF‐α alters the secretion of pituitary and thyroid hormones in lactating cows. This effect may contribute to the suppression of the lactogenic function of the mammary gland observed in cases of coliform mastitis with high circulating TNF‐α levels. 相似文献
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Specific cell populations in the pituitary glands of the rat, cat, pig, and human being were positive for thyroid-stimulating hormone (TSH), luteinizing hormone (LH), and follicle-stimulating hormone (FSH). When reacted with prediluted rabbit anti-human TSH, LH, and FSH, antisera were not positive for the demonstration of these hormones in the horse, cow, or dog. Immunocytochemical staining was obtained in the horse, cow, and dog by the use of a primary antiserum against a specific beta-subunit of bovine TSH. The immunocytochemical staining of TSH, LH, FSH, adrenocorticotropic hormone, growth hormone, prolactin, and calcitonin was examined by the peroxidase-antiperoxidase method, using standard commercially available kits. All species examined had a strong positive reaction in specific pituitary cell populations for adrenocorticotropic hormone, growth hormone, and prolactin. Sections of normal thyroid gland tissue had positive staining of C cells containing calcitonin at the dilution of 1:100 of the primary antibody in the rat, horse, cow, dog, cat, pig, and human being. 相似文献
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Clinico-chemical and radiometric methods, common in routine diagnosis in human medicine for in-vitro assessment of thyroid function, were tested for their applicability to calf. The assessment of protein-fixed iodine and of iodine extractable from stock, the thyroxine test, the tri-iodothyronine test, the tri-iodothyronine radio-immuno assay, and the effective thyroxine ratio test, basically, were applicable to diagnosis of thyroid function in calf. The thyrotrophin releasing hormone test, in conjunction with efforts to determine peripheral thyroid gland hormone concentration (in particular tri-iodothyronine), was also applicable to calf, although thyroid stimulation hormone with radio-immuno assay, another procedure in human medicine (specificity of thyroid stimulation hormone antibody), proved unsuitable for the determination of bovine thyroid stimulation hormone. 相似文献
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The effect of inhibiting the rise in cortisol concentrations that occurs at copulation upon luteinizing hormone release was studied in seven adult boars. Plasma samples were collected for assay of luteinizing hormone, testosterone and cortisol on a control day and before, during and after exposure to an estrous sow. The area under the curve was used to evaluate hormone production and treatment effects were evaluated by a paired Student's t-test. The 11 beta-hydroxylase inhibitor, metyrapone, was used to suppress glucocorticoid hormone production. Cortisol concentrations increased significantly (p less than 0.05) after breeding compared to values on the control day while treatment with metyrapone prior to breeding prevented the cortisol increase (p greater than 0.05). Although luteinizing hormone production increased significantly after copulation in both breeding experiments, metyrapone pretreatment resulted in a reduction of luteinizing hormone secretion (p less than 0.05). Testosterone production was also reduced in boars pretreated with metyrapone. The results suggest that the increased levels of cortisol occurring at copulation may enhance luteinizing hormone release in boars. 相似文献
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B.E. Rutland R.F. Nachreiner J.M. Kruger 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2009,23(5):1025-1030
Background: Methimazole suppresses thyroid hormone synthesis and is commonly used to treat feline hyperthyroidism. The degree of variation in thyroid hormone concentrations 24 hours after administration of methimazole and optimal time for blood sampling to monitor therapeutic efficacy have not been determined.
Objective: To assess thyroid hormone concentration variation in serum of normal and hyperthyroid cats after administration of methimazole.
Animals: Four healthy cats and 889 retrospectively acquired feline thyroid hormone profiles.
Methods: Crossover and retrospective studies . In the crossover study, healthy cats were treated with increasing doses of oral methimazole until steady state of thyroid suppression was achieved. Thyroid hormones and thyroid stimulating hormone (TSH) were serially and randomly monitored after methimazole. Paired t -tests and a 3-factor analysis of variance were used to determine differences between thyroid hormone concentrations in treated and untreated cats in the crossover study. Thyroid profiles from methimazole-treated hyperthyroid cats were retrieved from the Diagnostic Center for Population and Animal Health database and reviewed. Linear regression analysis evaluated relationships of dosage (mg/kg), dosing interval (q24h versus q12h), and time after methimazole to all thyroid hormone concentrations.
Results: All serum concentrations of thyroid hormones were significantly suppressed and TSH was significantly increased for 24 hours after administration of oral methimazole in healthy cats ( P < .005). In hyperthyroid cats, there were no significant relationships between thyroid hormone concentrations and time postpill or dosing interval.
Conclusions: Timing of blood sampling after oral methimazole administration does not appear to be a significant factor when assessing response to methimazole treatment. 相似文献
Objective: To assess thyroid hormone concentration variation in serum of normal and hyperthyroid cats after administration of methimazole.
Animals: Four healthy cats and 889 retrospectively acquired feline thyroid hormone profiles.
Methods: Crossover and retrospective studies . In the crossover study, healthy cats were treated with increasing doses of oral methimazole until steady state of thyroid suppression was achieved. Thyroid hormones and thyroid stimulating hormone (TSH) were serially and randomly monitored after methimazole. Paired t -tests and a 3-factor analysis of variance were used to determine differences between thyroid hormone concentrations in treated and untreated cats in the crossover study. Thyroid profiles from methimazole-treated hyperthyroid cats were retrieved from the Diagnostic Center for Population and Animal Health database and reviewed. Linear regression analysis evaluated relationships of dosage (mg/kg), dosing interval (q24h versus q12h), and time after methimazole to all thyroid hormone concentrations.
Results: All serum concentrations of thyroid hormones were significantly suppressed and TSH was significantly increased for 24 hours after administration of oral methimazole in healthy cats ( P < .005). In hyperthyroid cats, there were no significant relationships between thyroid hormone concentrations and time postpill or dosing interval.
Conclusions: Timing of blood sampling after oral methimazole administration does not appear to be a significant factor when assessing response to methimazole treatment. 相似文献
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The purpose of this study was to determine if there are specific steroid hormone aberrations associated with suspect endocrine alopecias in dogs in whom hypothyroidism and hyperadrenocorticism have been excluded. Steroid hormone panels submitted to the UTCVM endocrinology laboratory over a 7.5-year period (783 samples) from dogs with alopecia were reviewed. During this period, 276 dogs met the criteria for inclusion and were comprised of 54 different breeds. Approximately 73% of dogs had at least one baseline or post-ACTH stimulation steroid hormone intermediate greater than the normal range. The most frequent hormone elevation noted was for progesterone (57.6% of samples). When compared with normal dogs, oestradiol was significantly greater in Keeshond dogs and progesterone was significantly greater in Pomeranian and Siberian Husky dogs. Not all individual dogs had hormone abnormalities. Chow Chow, Samoyed and Malamute dogs had the greatest percentage of normal steroid hormone intermediates of the dogs in this study. Baseline cortisol concentrations were significantly correlated with progesterone, 17-hydroxyprogesterone (17-OHP) and androstenedione. Results of this study suggest that the pathomechanism of the alopecia, at least for some breeds, may not relate to steroid hormone intermediates and emphasizes the need for breed specific normals. 相似文献