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1.
After a brief exposition of the tasks about the protection against chemical, physical, and biological environmental risks, a demonstration will be given according to deliberations of our law system about the possibilities for veterinarians to cooperate in the legislative branches. A detailed examination on former activities in the fields of pollution and the food-chain are to serve as a model for the future legislative process in Germany with the intention to strive for a harmonization of the in parts independently developed legislative branches. The external harmonization, a long-term objective, is to be found in the form of an uniform environmental law. Veterinarians take a great interest to work in advance for this uniform law in the way they bring new perspectives by cooperating in the fields of environmental hygiene and toxicology for the protection of the environmental media, of species and the food-chain. In conclusion one finds a brief documentation about the impact of the adaptation of law and the process on the EC-level.  相似文献   

2.
The pathogenesis of a hypophysis-absces-syndrome in cattle is discussed on the basis of clinical (Espersen 1975) and pathomorphological (M?ller and Espersen 1975) investigations. It is concluded that several pathogenetic mechanisms are possible. A remarkable high incidence of the syndrome in recently ringed bulls point to the possibility of a porogenous spread from the nasal septum to the meninges and brain. The often occurring traumatic horn lesions with subsequent sinusitis suggest a porogenous spread from the sinus to the meninges and brain. On the other hand, traumatic horn lesions seem more often to occur as a secondary event and caused by automutilation, as a consequence of the pain, which is thought to accompany a primary meningo-encephalitis. The localization of the abscess in the hypophysis seems, in the majority of cases, to be a result of a primary, purulent meningo-encephalitis, with accumulation of pus from the brain ventricles to the infundibulum and pituitary cleft, due to gravitational forces. In some cases possibly as an extension from a basal meningitis. A direct, hematogenous metastasis to the frontal lobe of the pituitary is a further possibility. Ascending infection through a persistent cranio-pharyngeal duct and infection due to a primary cranial fracture represents other hypothetical, pathogentical possibilities. They have not been shown to occur. Severe clinical symptoms seem to be absent until the inflammation in the basal meninges and in the pituitary region attacks the adjacent cranial nerves, causing a paresis/paralysis.  相似文献   

3.
This report describes erythrocyte biochemical findings in an adult Spanish mustang mare that exhibited persistent methemoglobinemia, eccentrocytosis, and pyknocytosis that were not related to the consumption or administration of an exogenous oxidant. The methemoglobinemia was attributed to a deficiency in cytochrome-b5 reductase (Cb5R) activity, and the eccentrocytes and pyknocytes were attributed to a marked deficiency in reduced nicotinamide adenine dinucleotide phosphate-dependent glutathione reductase (GR) activity that resulted in decreased reduced glutathione concentration within erythrocytes. The GR activity increased to a near-normal value after addition of flavin adenine dinucleotide (FAD) to the enzyme assay, indicating a deficiency of FAD in erythrocytes. The methemoglobinemia, eccentrocytosis, and pyknocytosis were attributed to deficiency of FAD in erythrocytes because the GR and Cb5R enzymes use FAD as a cofactor. This deficiency in FAD results from a defect in erythrocyte riboflavin metabolism, which has not been documented previously in animals.  相似文献   

4.
Veterinary medical education is undergoing rapid change in terms of pedagogy, the demographics of the student body, and, in turn, the membership of the profession. Central to the value of the traditional curriculum and the total student experience is the small-group environment, both in client service and in clinical rounds. It is one of the few Socratic learning experiences in higher education today. Similarly, experience in private practice is of inestimable value in terms of developing people skills and a lasting sense of service and accountabilty. In a generation, the student body has transformed from vanishingly small numbers of women to a predominance of female students. However, the profession still is very white, in a world becoming more and more diverse. With a predominantly white faculty and student body today, this circumstance shows little promise of rapid enough change to maintain relevance to a workforce that, a generation from now, likely will be dominated numerically by people of color. The incorporation of various world views and the impact of stereotyping on performance are central to issues of success and failure of minorities and, in somewhat different ways, women in the veterinary medical profession. These issues must become better understood and addressed. And to accomplish this, and to address a host of other culturally important issues, a greater diversity of world views must be engaged in the work and planning of veterinary medical education and the profession at large. Addressing these issues in an environment in which the values of faculty and administrators are intensely focused on the science of veterinary medicine, and in which the participants hold dear a system that places value only on teaching, research, and clinical service, is a formidable undertaking and will require substantial reconsideration of faculty role and reward systems.  相似文献   

5.
The antispermatongenic effects of furazolidone on the testes of mature Wistar rats were investigated using histological and morphometric methods. The sections showed a varying degree of depopulation of the germinal epithelium, a shrinking and a deformation of the Tubuli contorti, and an enlargement of the intertubular lymphatic sinuses. The strain led to a standstill in the spermatogenesis at the primary-spermatocyte stage. After administering furazolidone, the following results could be seen: – a weightloss of up to 42.1% and a decrease in testes volume by up to 30.2% – a decrease in the volume of the nuclei of the Leydig-cells by up to 51.6% – a reduction in the diameter, perimeter and area covered by Tubuli seminiferi contorti of up to 33.5%, 30.8%, and 53.4%, respectively – an increase in the number of Tubuli seminiferi contorti per mm2 by up to 44.8% – a decrease in the percentage of Tubuli seminiferi contorti of the total testes tissue by up to 39.1%  相似文献   

6.
The effect of fasting and refeeding on total antioxidant status (TAS), glutathione peroxidase (GSH-Px) activity and concentration of some non-enzymatic antioxidant compounds was studied in cockerels and pullets. Blood was collected before and after 48-h fasting and 24 h after refeeding. In cockerels, fasting resulted in a significant decrease of TAS and uric acid concentration. After refeeding, the concentration of TAS remained significantly lower as compared to the control level. At the same time, blood plasma level of total lipids increased in comparison to the control and post-fasting values. In pullets, fasting resulted in a significant decrease of whole blood haemolysate GSH-Px activity and blood plasma concentrations of albumin and uric acid. Simultaneously, a significant increase in total lipids and cholesterol was obtained. In pullets, refeeding resulted in a further decrease of TAS to undetectable values, a significant decrease of blood plasma cholesterol, and a significant increase of GSH-Px in the whole blood haemolysate and in blood plasma uric acid content. The results indicate that fasting has a negative impact on the antioxidant defence system of the blood, which leads to a reduced resistance to oxidative stress in both cockerels and pullets. However, pullets seem to be more susceptible to fasting-provoked oxidative stress than cockerels.  相似文献   

7.
PATIENT GROUP: The majority of cats will develop radiographic evidence of degenerative joint disease by the time they are 12 years of age, and many will suffer from a decline in quality of life associated with undiagnosed and untreated orthopedic disease. PRACTICAL RELEVANCE: A focused, efficient orthopedic examination, including gait observation and palpation (awake and under sedation), supplemented with appropriate history, is key in ruling in, or out, clinically important musculoskeletal disease. Identifying problems assists in both developing a diagnostic plan and monitoring response to treatment. CLINICAL CHALLENGES: Many clinicians feel uncomfortable in their ability to reliably perform an orthopedic examination in the cat, and diagnosis and evaluation of response to treatment in cats with orthopedic disease can be challenging. Hands-on training in feline orthopedic examination is limited in many veterinary curricula. Additional constraints may include failure to obtain important information in the history that indicates feline orthopedic disease, lack of appropriate facilities in which to conduct a complete orthopedic examination, and inability to obtain the most important information during the time available to conduct the examination. These problems can create gaps in the practitioner's ability to provide excellent care for a large proportion of the feline population. GOALS: The above challenges can mostly be overcome with advanced planning and with consideration of the unique behavioral aspects related to feline handling. As discussed in this review, the aim of the initial orthopedic examination is to localize the problem to a specific limb, ideally to a region or joint of the limb, which can further direct diagnostics such as radiography or arthrocentesis. This should provide a basis for follow-up and assessment of whether treatment strategies are effective.  相似文献   

8.
Turkey knockdown was diagnosed in three of five flocks of hen turkeys on a single farm within a 12-mo period. The age of birds in the flocks affected ranged from 6 wk 2 days to 7 wk 4 days. The attack rate ranged from 0.02% to 0.30% with a case fatality rate in affected birds ranging from 0 to 74%. The diagnosis was made on the basis of clinical signs and histopathologic lesions associated with knockdown. The feed in all flocks contained bacitracin methylene disalicylate and monensin (Coban). Affected birds were recumbent, demonstrated paresis, and were unable to vocalize. Postmortem examination revealed few significant lesions although pallor of the adductor muscles and petechiation in adductor and gastrocnemius muscles were noted. Birds that had been recumbent for extended periods were severely dehydrated. Consistent microscopic lesions included degeneration, necrosis, and regeneration of adductor, gastrocnemius, and abdominal muscles. No lesion in cardiac tissue was noted. Results of our investigation indicated that changes in water consumption, vitamin E status, and brooder to finisher movement correlated with the occurrence of knockdown. Turkey knockdown was defined in 1993 as any condition identified in a turkey flock that has affected the neuromuscular system to a degree that a turkey is unable to walk or stand. This definition was later modified to...neuromuscular or skeletal systems to a degree that a turkey is unable to walk or stand properly. Knockdown may be associated with numerous feed, management, or disease factors alone or in combination. Dosage of monensin, feed restriction/gorging, water restriction, heat stress, copper, mycotoxins, sodium chloride in feed, and sulfa drugs have all been suggested as contributing factors; however, laboratory studies to duplicate this have not been successful. This report presents observations from a single farm at which three of five hen flocks in a single year experienced knockdown. When a flock was reported as affected, a detailed investigation was initiated within 3 hr. The fifth flock was followed on a twice weekly basis from 0 to 8 wk of age to determine if initiating events were evident, but knockdown did not occur.  相似文献   

9.
The trichostrongylid and strongylid egg output in a group of ewes lambing in March, the middle of the usual lambing time in the Netherlands, was compared with counts in groups of older ewes and yearling ewes lambing in May-June and with counts in a group of barren ewes. The groups lambing in March showed only a rise related to parturition date as normally seen in the Netherlands. A few of the late lambing ewes showed a slight rise in spring, but all of them showed a peri-parturient rise related to parturition date. In the late lambing ewes and in the barren ewes egg counts due to reinfection were seen in summer. It is concluded that under the present circumstances a true spring rise, the calendar phenomenon, occurs very irregularly, while a peri-parturient rise related to the parturition date is a common phenomenon. The occurence of high egg counts in summer, excluding consideration on the barren ewes, in the late lambing ewes only, suggests that changing the traditional husbandry system may influence the epidemiological pattern of the trichostrongylid infections.  相似文献   

10.
Reasons for performing study: The flexion test is used routinely as part of lameness and prepurchase examinations. However, little is known about the mechanisms that cause a positive response to a flexion test. Objective: To determine which anatomical regions play a role in a positive outcome of a flexion test of the distal aspect of a forelimb in a nonlame horse. Methods: Eight clinically sound Dutch Warmblood horses were subjected to a standardised flexion test (force 250 N, time 60 s) inducing a consistent lameness. To discriminate between different areas of the distal aspect of a forelimb, effects of various nerve blocks on the outcome of the flexion test were investigated. Low palmar digital, palmar at the abaxial aspects of the base of the proximal sesamoids, high palmar, ulnar and low 4‐point nerve blocks were performed. Flexion test induced lameness was scored before and after each nerve block in separate sessions. Results: The low palmar digital nerve blocks and nerve blocks of the palmar nerves at the abaxial aspect of the base of the proximal sesamoid bones had no significant effect on the flexion test induced lameness score. The ulnar, high palmar and, most dramatically, the low 4‐point nerve blocks all caused a significant (P<0.05) reduction in the flexion test induced lameness score. Conclusions: Anatomical structures (soft tissue nor synovial structures) located distal to the metacarpophalangeal joint appear to contribute only minimally to the outcome of a positive flexion test of the distal aspect of a forelimb in a clinically nonlame horse. The structures in the region of, and including, the metacarpophalangeal joint appear to contribute most to a positive flexion test of the distal aspect of a forelimb in a nonlame horse. Potential relevance: The flexion test of the distal aspect of a forelimb may be sensitive for investigating the metacarpophalangeal joint region in horses free from lameness, but may be less relevant for structures distal to this region.  相似文献   

11.
1. Data from 9 experiments in which broiler breeder pullets had been photostimulated at two or more ages were integrated to produce a model to predict age at 50% egg production following a single increase in photoperiod during rearing. 2. It was clear that the photosexual response in broiler breeders was strongly influenced by the feed allowance and hence the rate of prepubertal growth. Regressions for birds given either a constant photoperiod or a single increase indicated that mean age at 50% lay advances by 2 d for every 100-g increase in body weight at 20 weeks. 3. The general response of broiler breeders was similar to that previously reported for egg-type pullets, but with important changes in the ages at which the birds progressed from one physiological state to the next, depending on body weight. 4. Broiler breeders, unlike modern egg-type pullets, exhibit juvenile photorefractoriness and, depending on their body weight, require up to 20 weeks to dissipate this (faster growth allows quicker dissipation). As a consequence, a group of birds grown to a typical weight of 2.1 kg at 20 weeks do not start to be photoresponsive until about 10 weeks and are not uniformly responsive until 19 or 20 weeks. A transfer to a stimulatory photoperiod before a bird has dissipated photorefractoriness causes a delay of about 3 weeks in its sexual development, and this results in a bimodal distribution of ages at maturity when a flock is photostimulated between 10 and 20 weeks. 5. Once photosensitive, the response of broiler breeders to an increment in photoperiod is between 0.50 and 0.65 of that observed in ISA Brown egg-type pullets. However, a flock of broiler breeders with typical feed restriction starts to mature spontaneously under the influence of the initial photoperiod from about 25 weeks. 6. There is a difference of only 1 to 3 d in age at 50% egg production between a flock transferred to 11 or 12 h followed by further increases to 15 or 16 h and one increased abruptly to one of these photoperiods, and so this model can be used to predict maturity in a commercial flock of birds even though they are likely to be given a stepped, rather than a single, increase in photoperiod.  相似文献   

12.
An epidemic of acute respiratory disease associated with bovine respiratory syncytial virus (BRSV) occurred during the winter and spring of 1995 in two neighbouring veterinary districts in the south-eastern part of Norway.The objective of this study was to describe the time course of the outbreak associated with BRSV in the cattle herds, and to determine the association between selected herd factors and the risk of experiencing a herd outbreak of acute respiratory disease.Data from 431 cattle herds on the dates of disease occurrence, location of the farms, herd size, age profile and production type were collected retrospectively for 1995. The risk of acute respiratory disease occurring in a cattle herd was related to the herd size as well as the type of production, with an expressed interaction between these two variables. From the Cox proportional-hazards model, the risk of a herd outbreak in a mixed herd of 20 animals was estimated to be 1.7-times greater than in a dairy herd and 3.3-times greater than a beef herd (reference category) of a comparable size. On increasing the herd size to 50 animals, the risk increased 1.3-fold for a mixed herd, 3.3-fold for a dairy herd, and 2.1-fold for a beef herd, compared to the risk for a corresponding type of herd of 20 animals.  相似文献   

13.
Reasons for performing the study: The ability of horses to habituate to novel objects influences safety in the horse–human relationship. However, the effectiveness of different habituation techniques has not been investigated in detail. Objectives: 1) To investigate whether horses show increased stress responses when negatively reinforced to approach novel objects, compared with horses allowed to voluntarily explore the objects and 2) whether a negatively reinforced approach facilitates object habituation. Methods: Twenty‐two 2–3‐year‐old Danish Warmblood geldings were included. Half of the horses (NR group) were negatively reinforced by a familiar human handler to approach a collection of novel objects in a test arena. The other half were individually released in the arena and were free to explore the objects (VOL group). On the next day, the horses were exposed to the objects again without a human handler, to investigate the rate of habituation. Behavioural and heart rate responses were recorded. Results: All VOL horses initially avoided the unknown objects, whereas the handler was able to get all NR horses to approach and stand next to the objects within the first 2 min session. The NR horses had a significantly longer duration of alertness and a higher max heart rate in the first session. On the next day, however, NR horses spent significantly less time investigating the objects and had a shorter latency to approach a feed container, placed next to the objects, indicating increased habituation. Conclusion: A negatively reinforced approach to novel objects increases stress responses during the initial exposure but facilitates habituation in young horses. Potential relevance: Although a negatively reinforced approach appears beneficial for habituation, the procedure should be carefully managed due to increased stress responses in the horse, which may constitute a safety risk. Further experiments should aim to investigate differences in stimulus intensity.  相似文献   

14.
The M. extensores carpi radiales have been studied in detail in humans. The aim of this study was to carry out a comparative anatomical study of these muscles using four species--rabbit, cat, dog and sheep--and to propose a 'systematization' in a few standard models according to the morphological variations seen. In these species, there is marked morphological evolution, with two muscles in humans, one in sheep and a more or less distinct division of the muscle in the rabbit, cat and dog. Examination of the vascularization and nerve supply enables us to determine degrees of division in species with similar muscle morphology. Thus we were able to distinguish three morphological types which allow us to infer the morphological evolution of the M. extensores carpi radiales and to estimate the point at which one muscle became two. However, there is a strong chance that some process of convergence may have occurred, and in pentadactyl species many elements represent the plesiomorphis and are therefore of little use in constructing a classification on the basis of evolution.  相似文献   

15.
Keap1-Nrf2/ARE信号通路及其在畜禽抗氧化中的研究进展   总被引:1,自引:0,他引:1  
正常生理状态下,动物体内自由基的产生和清除处于稳定的动态平衡,但发生氧化应激时,体内自由基产生的量超过自身清除能力,引起氧化系统和抗氧化系统的失衡,造成氧化损伤。而Keap1-Nrf2/ARE信号通路的激活在预防氧化应激引起的细胞和组织损伤、维持氧化还原平衡和蛋白质稳态以及调节炎症方面具有关键作用。Keap1是Nrf2的胞浆抑制蛋白,在正常生理状态下,Nrf2与Keap1结合而发生泛素化和蛋白酶体降解,使细胞核内Nrf2的含量维持在一个相对较低的水平。在氧化应激条件下,Keap1对Nrf2的泛素化和降解的能力减弱,细胞核中Nrf2积聚,Nrf2与抗氧化反应元件(ARE)结合后启动下游一系列保护性基因的表达,使机体从氧化应激状态恢复到正常的生理状态。氧化应激参与多种病理生理变化,对畜禽的生产性能、生长发育、繁殖性能、肉品质等有负面影响,Keap1-Nrf2/ARE信号通路是细胞内最重要的抗氧化应激通路之一,对动物的健康保护极其重要。作者总结了Keap1-Nrf2/ARE信号通路的基本结构和活化机制及其在畜禽抗氧化中的研究进展,阐述了其在提高畜禽的抗氧化、抗炎能力和在肉品质中的重要作用,以期为缓解当前畜禽业中严重的氧化应激和炎症提供理论依据。  相似文献   

16.
Decapitation of spermatozoa was recorded in a young boar as a consequence of epididymitis and in a young dog (mastiff) and a young bull (Brown Swiss breed) as a congenital cause of the subfertility and sterility of the affected animal. Decapitation of spermatozoa as a consequence of an inflammation led to the sterility of the breeding male and affected 52 to 68% of the spermatozoa. The motility of the spermatozoa was reduced considerably (10 to 20%) and the flagella were not observed to move without the heads. In cases of congenital decapitation of spermatozoa, sperm motility in the dog and bull was reduced, but the flagella were observed to move without the heads. Decapitation affected 15 to 42% of the spermatozoa and most frequently it was accompanied by a narrowing of head base and by the presence of a protoplasmic drop, located proximally. Further developmental changes, affecting the flagella of the sperms, were observed in the dog. The mentioned morphological changes led to infertility in the dog and to a substantial reduction of fertility in the bull. After natural mating of the bull with a superovulated cow, the ten eggs obtained included four blastocysts, two were degenerated, and four were unfertilized.  相似文献   

17.
Veterinarians in the United States and abroad are faced with growing public concern for the welfare of animals, particularly those in production. To prepare veterinarians to exert the leadership expected by the public and industry, steps should be taken to provide instruction in animal welfare at veterinary colleges. The ultimate goal is to offer courses in animal welfare in a consistent manner on a global scale, utilizing existing expertise in an efficient and cost-effective manner. Given the intense curricula of veterinary schools and the scarcity of instructors trained in animal welfare, a nontraditional approach is needed to educate veterinary students in the United States and abroad in animal welfare. Michigan State University (MSU) is developing a graduate-level, online interactive course in animal welfare assessment. The course will approach the topic of animal welfare education from a holistic, multidisciplinary standpoint (encompassing ethics, economics, and behavior) and address issues important to the general public and the international community. The MSU course will draw on renowned international animal welfare experts, allowing students to receive high-quality education that would be difficult in any other circumstance. The course will bridge an important gap in the veterinary curriculum and offer a complete and congruous education in animal welfare to veterinarians worldwide. The MSU course will also serve as a model for collaboration in content assembly and course delivery, by using technology to leverage global expertise in the interests of educational equity. In addition to innovative technology, such as the use of Web-collaboration software to create the course, a variety of media that enable students to interact with the material will also be incorporated throughout the course. Thus, the course will not only utilize the Internet to provide access to high-quality material, but will also require the active participation of the student, which is needed for effective learning.  相似文献   

18.
The life and work is told of John Pottie (1832-1908), a Scotsman who graduated from Edinburgh Veterinary College in 1858. A year later, he contracted to provide veterinary care to a consignment of horses bound for Australia. Once there, he founded a firm that has survived to the present day, still marketing products that originated in his own veterinary remedies. John Pottie brought with him a European tradition of livestock care and treatment that was epitomised in Clater's title and book, Every man his own farrier. His career is of interest for several reasons. Firstly it is because he used this tradition to launch a business enterprise in a new and different market in Australia. Secondly, although his training lay in what may be termed the pre-scientific era of the profession's history, he was able to adapt old traditions successfully to the changes that came in the age of Pasteur and Koch. Finally, the manner in which he did this, besides demonstrating his business acumen, also shows how the professional veterinary qualification gained in value in a new age of science.  相似文献   

19.
Historical (1994 to 1998) market hog price, feed costs, and other expenses were combined with average industry production values in an economic analysis of replacement gilt investments in a 600-sow farrow-to-finish operation. Based on historical data, a replacement gilt must remain in the breeding herd for three parities or more to attain a positive Net Present Value (NPV). The earlier (lower parity) a sow reaches a positive NPV, the more profitable the operation. Sensitivity analyses were used to evaluate the impact of assumption changes on the parity in which a positive NPV is attained. Assuming all other items are held constant, an approximate 5% change in number of pigs born alive per litter, market hog price per kilogram, or feed cost per market hog changes the parity in which a positive NPV is attained from parity three to parity two or four, depending on the direction of change. Assuming all other items are constant, a 35% increase in replacement gilt purchase price increases the parity from three to four in which a positive NPV is realized. Similarly, an equity decrease from 50 to 30% in the modeled swine operation also increases the parity in which a positive NPV is attained from three to four. Opportunity exists for commercial swine producers to increase the profitability of their replacement gilt investments by increasing the number of productive parities the sow produces. Swine producers should focus on management and genetic factors to improve sow longevity and hence, the profitability of a replacement gilt investment.  相似文献   

20.
Veterinarians are integrally involved in the maintenance of a safe and sufficient food supply; this involvement may be put to the test when a crisis — particularly a nuclear crisis — occurs. Few people can be said to be experts in how to ensure a safe food supply in a nuclear crisis. However, a working knowledge of radionuclides and how they behave in the food system, and the ability to identify high-risk foods and high-risk consumers in a crisis situation should be a part of the education of all veterinarians. In this paper I review those features of postdisaster radionuclide contamination of the food chain most relevant to veterinary activities in ensuring a safe food supply.  相似文献   

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