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1.
抗营养因子是存在于饲料中,阻碍饲料营养成分在体内消化吸收、代谢,导致动物体病变,影响动物生长、繁殖性能的物质。消除抗营养因子是保证饲料营养成分的有效利用、保证动物正常生长发育与健康,降低养殖生产成本的重要措施。为了深入探索饲料抗营养因子消除方法,文章对抗营养因子的抗营养机理和影响后果、消除方法进行了概述。  相似文献   

2.
Animals that hunt and scavenge are often exposed to a broad array of pathogens. Theory predicts the immune systems of animals specialized for scavenging should have been molded by selective pressures associated with surviving microbial assaults from their food. Spotted hyenas (Crocuta crocuta) are capable hunters that have recently descended from carrion feeding ancestors. Hyenas have been documented to survive anthrax and rabies infections, and outbreaks of several other viral diseases that decimated populations of sympatric carnivores. In light of the extreme disease resistance manifested by spotted hyenas, our objective was to identify tools available for studying immune function in spotted hyenas and use these tools to document the hyena antibody response to immunization. Domestic cats (Felis catus) are the closest phylogenetic relatives of hyenas that have been studied in detail immunologically, and we hypothesized that anti-cat isotype-specific antibodies would cross react with hyena immunoglobulin epitopes. We used ELISA and Western blots to test isotype-specific anti-feline antibodies for specific cross-reaction to hyena Ig epitopes. Molecular weights of heavy (IgA, IgG, IgM) and light chains of hyena immunoglobulins were determined by protein electrophoresis, and as expected, they were found to be similar to feline immunoglobulins. In order to further validate the cross-reactivity of the anti-feline antibodies and document the hyena humoral response, eight spotted hyenas were immunized with dinitrophenol conjugated keyhole limpet hemocyanin (DNP-KLH) and serum anti-DNP responses were monitored by enzyme-linked immunosorbent assay (ELISA) for one year. The full array of isotype-specific antibodies identified here will allow veterinarians and other researchers to thoroughly investigate the hyena antibody response, and can be used in future studies to test hypotheses about pathogen exposure and immune function in this species.  相似文献   

3.
An 11-yr-old captive-born female striped hyena (Hyaena hyaena) acutely developed lameness and swelling of the left front foot with anorexia, depression, and lethargy. Hematologic evaluation revealed regenerative anemia, azotemia, and other mild serum electrolyte and mineral abnormalities. Twenty radiographically visible coins and 10 coin fragments were removed by laparotomy and gastrotomy following unsuccessful medical therapy. The animal died during anesthetic recovery. Zinc serum levels were 41.0 ppm at first presentation and 36.0 ppm at the time of surgery, compared with concentrations of 1.78 ppm and 2.82 ppm for serum taken from this female and a male hyena 3 mo previously. Zinc toxicosis was diagnosed based on the similarity of clinical signs to those described in dogs, presence in the stomach of pennies minted after 1982 (when the zinc content of U.S. pennies was increased substantially), necropsy findings, and elevated serum and liver zinc values. The case highlights the risk posed by penny ingestion for subsequent zinc toxicosis in captive omnivores.  相似文献   

4.
A 10.5-yr-old male spotted hyena (Crocuta crocuta) developed acute, severe erythematous and ulcerative dermatitis of the hindquarters, feet, face, and ears 19 days after receiving a recombinant canary pox vectored canine distemper vaccine. Biopsies of the lesions supported a diagnosis of erythema multiforme (EM), which is an immune-mediated disorder that can occur days to months after exposure to antigenic stimuli. During the lengthy recovery, esophageal regurgitation and ulceration developed either as complications of the disease or secondary to therapy. The esophageal disease was managed with metoclopramide, sulcrafate, omeprazole, and frequent feedings. The distemper vaccine is postulated to have been the inciting cause of EM in this animal.  相似文献   

5.
微生态制剂是由活体微生物制成的生物活性制剂,它能促进动物消化道内微生态平衡的建立,提高机体对饲料的消化吸收效率和自身抗病能力,达到防治疾病和促进生长的双重作用。本文主要对微生态制剂的菌种选择、作用机理及应用现状等方面进行了阐述,并提出了研究方向。  相似文献   

6.
主要介绍了枯草芽胞杆菌对动物的生长性能、免疫指标和抗病力的影响,以及对养殖水体的净化作用,以期为在畜牧生产实践中合理利用枯草芽胞杆菌提供一定的理论依据。  相似文献   

7.
反刍动物过量采食精料会引起瘤胃内乳酸蓄积,使体内酸碱平衡失调、体液pH值下降,重者可导致死亡,轻者影响生长发育。本试验选用育肥期日龄、体重差异不显著的肉牛40头,随机分成4组,按不同日饲喂精料量分组喂养,通过检测生理指标、调整日饲喂精料量,论证长期隐性代谢性酸中毒(瘤胃液pH值在5~5.52、尿液pH值在5.05~5.61之间)对肉牛育肥效果的影响。结果显示在育肥过程中隐性代谢性酸中毒牛群与健康牛群相比增重比低了11.61个百分点。  相似文献   

8.
OBJECTIVE: To examine the effectiveness of mass medication with long acting antibiotics at feedlot entry on lot-fed Australian domestic cattle during a period of high risk for bovine respiratory disease (BRD). DESIGN: Systematic allocation at feedlot entry of tilmicosin, long acting oxytetracycline or no antibiotic treatment, to cattle lot fed for the Australian domestic market. Comparisons of growth rate, disease occurrence and mortality were made between the groups at the conclusion of the feeding period. RESULTS: Cattle medicated with tilmicosin at 10 mg/kg body weight on entry to the feedlot grew 0.08 kg/d faster than cattle medicated with oxytetracycline at 20 mg/kg body weight and non-medicated cattle. There was no significant difference in growth rate between oxytetracycline medicated cattle and cattle not medicated with antibiotic at feedlot entry. Cattle medicated with tilmicosin at feedlot entry had 8 fewer cases of disease per 100 animals compared with cattle not medicated with antibiotic at feedlot entry. There was no significant difference in disease occurrence between oxytetracycline medicated cattle and those not medicated with antibiotic at feedlot entry. CONCLUSION: Mass medication with tilmicosin at feedlot entry of cattle destined for the Australian domestic market may be used to reduce disease occurrence and increase growth rate during periods of high risk for BRD.  相似文献   

9.
小鼠经凋亡抑制基因免疫后,从3周龄到8周龄基因免疫组小鼠平均体重比对照组分别低0.48、1.18、1.16、1.35、0.99、0.85g。基因免疫后的头2周,小鼠生长速度明显低于对照组,且生长速度的差异随着免疫时间的增加而减小。这提示该基因与小鼠生长有关,如果用基因治疗方法增加凋亡抑制基因表达量,有可能增加小鼠生长速度。将凋亡抑制基因作为候选基因,研究它对家畜生长的遗传效应,对家畜繁育有重要的意义。  相似文献   

10.
核苷酸对动物的营养作用及其在饲料中应用前景分析   总被引:3,自引:0,他引:3  
核苷酸具有许多生理生化功能 ,人和动物体内能够从头合成核苷酸 ,但在某些情况下 ,如机体迅速生长、受到免疫挑战时 ,一些器官、组织内源合成核苷酸不能满足机体的需要。日粮来源的核苷酸对胃肠道的生长发育、免疫系统、肝功能及脂代谢具有重要作用。核苷酸或核酸是一种无毒无害无三致的安全的添加剂 ,在动物生产应用核苷酸或核酸将具有促进动物生长和改善肉质的作用 ,作为新一代的饲料添加剂很有发展前途。  相似文献   

11.
核苷酸具有许多生理生化功能.人和动物体内能够从头合成核苷酸,但在某些情况下,如机体迅速生长、受到免疫挑战时,一些器官、组织内源合成的核苷酸不能满足机体的需要.日粮来源的核苷酸对胃肠道的生长发育、免疫系统、肝功能及脂肪代谢有重要作用.动物生产中,日粮核苷酸是一种半必需营养素.  相似文献   

12.
霉菌毒素免疫抑制作用的研究进展   总被引:1,自引:1,他引:0  
戈娜  袁慧 《中国畜牧兽医》2008,35(3):126-128
霉菌毒素是霉菌的有毒代谢产物,对动物机体最重要的危害作用就是能够抑制动物机体的免疫机能,引起动物生长缓慢,生产性能下降,对疾病的抵抗能力降低,造成长远的经济失。同时霉菌毒素之间还有对免疫系统的协同抑制作用。作者针对饲料中几种主要的霉菌毒素对动物机体免疫抑制作用作一综述。  相似文献   

13.
肠道既是动物机体消化吸收营养物质的主要器官,也是体内最大的免疫器官,同时还发挥着重要的屏障功能,因此肠道健康是动物健康的必要条件。锌是动物必需的微量元素之一,对动物生长发育、抗氧化和免疫等生理功能具有重要调控作用。长期以来,饲料中补充营养性锌源以无机硫酸锌为主,近年来蛋氨酸锌、乳酸锌和甘氨酸锌等有机锌源的使用越来越普遍。关于有机锌对动物肠道健康的调控作用已成为锌营养领域研究热点之一。本文从有机锌对肠道黏膜屏障、肠道免疫和肠道生物屏障的影响等方面综述了有机锌对动物肠道健康的调控作用,为有效利用有机锌改善动物健康提供重要的科学依据和理论支撑。  相似文献   

14.
Body weight, length, width and depth at two growth stages were observed for a total of 5015 individuals of GIFT strain, along with a pedigree including 5588 individuals from 104 sires and 162 dams was collected. Multivariate animal models and a random regression model were used to genetically analyse absolute and relative growth scales of these growth traits. In absolute growth scale, the observed growth traits had moderate heritabilities ranging from 0.321 to 0.576, while pairwise ratios between body length, width and depth were lowly inherited and maximum heritability was only 0.146 for length/depth. All genetic correlations were above 0.5 between pairwise growth traits and genetic correlation between length/width and length/depth varied between both growth stages. Based on those estimates, selection index of multiple traits of interest can be formulated in future breeding program to improve genetically body weight and morphology of the GIFT strain. In relative growth scale, heritabilities in relative growths of body length, width and depth to body weight were 0.257, 0.412 and 0.066, respectively, while genetic correlations among these allometry scalings were above 0.8. Genetic analysis for joint allometries of body weight to body length, width and depth will contribute to genetically regulate the growth rate between body shape and body weight.  相似文献   

15.
Background: Foreign body aspiration is a differential diagnosis for acute or chronic cough that requires medical or surgical management in animals. Hypothesis: Success of bronchoscopy in airway foreign body removal is dependent on the size of the animal, duration of clinical signs, and location of the foreign body. Animals: Thirty‐two dogs and 5 cats with airway foreign bodies identified at the UC Davis Veterinary Medical Teaching Hospital. Methods: Retrospective case study evaluating the role of duration of clinical signs and body size in successful bronchoscopic removal of foreign bodies. In addition, radiographic localization of disease was compared with bronchoscopic identification. Bronchoalveolar lavage (BAL) culture and cytologic findings are reported. Results: Bronchoscopy was successful for removal of airway foreign bodies in 76% of animals (24/28 dogs and 2/5 cats), and in dogs was independent of duration of clinical signs or body size. One‐third of thoracic radiographs lacked distinctive features of an airway foreign body, and therefore radiography was unable to predict the affected site. BAL fluid at the site of the foreign body contained more neutrophils and more often had intracellular bacteria than lavage fluid from a separate site. Conclusions and Clinical Importance: Bronchoscopy was successful in removing airway foreign bodies regardless of animal size or long duration of clinical signs. Results of this study confirm the utility of bronchoscopy with lavage in management of suspected foreign bodies, even in the absence of localizing radiographic findings.  相似文献   

16.
杜泊羊与蒙古羊杂交羔羊生长发育规律的研究   总被引:1,自引:0,他引:1  
选择出生重及出生日期相近、生长发育正常的杜泊羊与蒙古羊杂交羔羊60只,进行杜蒙杂交羔羊早期断奶对生长发育规律影响的研究。结果表明,从出生到4月龄时期杜蒙杂交羔羊体重绝对增长和体尺(体高、体斜长、胸围和管围)的增长速度很快,该时期为杜蒙羔羊生长的高峰期。根据杜蒙羔羊的生长发育规律,加强羔羊生长高峰期的营养需要和饲养管理,对当地畜牧业的生产与发展具有重要意义。  相似文献   

17.
瘦素(leptin,LEP)是白色脂肪分泌的一种蛋白质激素,在哺乳动物中,LEP是一种16-ku的肽类激素,在能量平衡的神经内分泌和外周调节中发挥重要作用,是反应体脂含量和调节体重、摄食的重要信号因子。在人类疾病方面,LEP基因的表达对很多疾病的发生起着重要的调控作用,尤其是LEP基因的突变可能导致肥胖、糖尿病和乳腺癌等疾病;在畜牧生产上,LEP基因的表达对牛、羊和猪的采食和生长性状影响显著。为了加深对LEP基因的认识,作者对LEP基因的结构及LEP的分布、结构和功能进行了总结,并对近几年LEP基因在疾病和畜牧生产方面的研究进展进行了综述。  相似文献   

18.
An adult female hyena and her two 4-month-old cubs were found to have multifocal areas of alopecia and dermatitis. Dermatophyte culture of hair and skin samples collected from the lesions yielded Trichophyton mentagrophytes. None of 10 other animals in the colony that were tested were found to have dermatophytes. Lesions were treated twice, at 3-week intervals, with thorough cleansing with chlorhexidine scrub followed by topical application of antifungal agents. Lesions resolved, and dermatophyte culture of samples collected 6 weeks after the initiation of treatment did not yield growth.  相似文献   

19.
A generalized Michaelis-Menten equation for the analysis of growth   总被引:1,自引:0,他引:1  
The functional form W = (W0Kc + Wf t(c)) /(Kc + t(c)), where W is body size at age t, W0 and Wf are the zero- and infinite-time values of W, respectively, and K and c are constants, is derived. This new generalized Michaelis-Menten-type equation provides a flexible model for animal growth capable of describing sigmoidal and diminishing returns behavior. The parameters of the nonlinear model are open to biological interpretation and can be used to calculate reliable estimates of growth traits, such as maximum or average postnatal growth rates. To evaluate the new model, the derived equation and standard growth functions such as the Gompertz and Richards were used to fit 83 growth data sets of different animal species (fish, mice, hamsters, rats, guinea pigs, rabbits, cats, dogs, broilers, turkeys, sheep, goats, pigs, horses, and cattle) with a large range in body size. A comparative study was carried out based on mathematical, statistical, and biological characteristics of the models. The statistical goodness-of-fit achieved with the new model was similar to that of Richards, and both were slightly superior to the Gompertz. The new model differed from the others with respect to some of the estimated growth traits, but there were highly significant correlation coefficients between estimates obtained with the different models, and the ranking of animals based on growth parameters computed with the new function agreed with the rankings computed by the other models. Therefore, the new model, with its variable inflection point, was able to adequately describe growth in a wide variety of animals, to fit a range of data showing sigmoidal growth patterns, and to provide satisfactory estimates of traits for quantifying the growth characteristics of each type of animal.  相似文献   

20.
胰岛素样生长因子2(insulin-like growth factor 2,IGF2)作为胰岛素类激素家族中重要成员之一,广泛参与机体众多生理代谢过程,在癌症发生、神经调节、糖代谢疾病、骨质疏松、肌肉发育和脂肪沉积等方面具有重要的作用,其功能行使主要通过与受体IGF1R和IGF2R结合或与胰岛素样生长因子结合蛋白IGFBPs和IGF2BPs竞争性结合发挥功能。鉴于IGF2基因在肌肉发育和脂肪沉积中的重要作用,发掘IGF2基因相关分子标记并解析其内在调控机理,在畜牧生产中具有重要的意义。研究发现,众多IGF2基因遗传变异与动物的生长发育之间存在显著相关关系,其可能通过影响IGF2基因印记、甲基化状态、转录因子结合或miRNA靶向结合型转录后调控等方式发挥作用。因此,文章综述了IGF2基因表达调控模式,包括IGF2与其受体的调控关系,基因印记与miRNA参与的表观遗传调控,转录因子对其的调节作用,遗传变异等方面的内容,以期为IGF2基因在动物生长发育调控相关研究中提供相应的借鉴,为分子育种提供有效线索。  相似文献   

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