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1.
目的检测三株柔嫩艾美耳球虫对六种药物的耐药性,为防治球虫病制定临床用药方案提供依据。方法鸡体实验法检测巢湖、六安、肥东三株柔嫩艾美耳球虫对马杜拉霉素、盐霉素、莫能菌素、磺胺喹嗯啉钠、地克珠利、妥曲珠利的耐药性,以抗球虫指数(ACI)、病变记分减少率(RLS)、相对盲肠卵囊产量(ROP)和最适抗球虫活性百分率(POAA)四项指标综合判定。结果巢湖株对地克珠利,盐霉素与莫能菌素轻度耐药,对马杜拉霉素中度耐药,对托曲株利和磺胺喹嗯啉钠重度耐药,六安株对地克株利与托曲株利重度耐药,对磺胺喹嗯啉钠中度耐药,对盐霉素轻度耐药,对马杜霉素敏感,肥东株对磺胺喹嗯啉钠完全耐药,对莫能菌素重度耐药,对马杜霉素与盐霉素轻度耐药,对地克珠利与托曲珠利中度耐药。结论3个地区的柔嫩艾美耳球虫对供试药物已产生不同程度的耐药性。  相似文献   

2.
Reasons for performing study: There is a need for study of a method for restoring a ventrally positioned uterus to a horizontal position involving fertility of mares with delayed uterine clearance. Hypothesis: A ventrally‐angled uterus can be elevated to a horizontal position using a laparoscopic technique. Objective: To develop a laparoscopic technique of imbricating the mesometria to elevate the uterus to a horizontal position. Methods: The right and left mesometria of 5 pluriparous mares, all barren for 1–8 years (mean 3.8 years), with a pendulous, ventrally‐angled uterus were shortened laparoscopically, by imbrication, with the mares standing, to raise the uterine body and horns to a horizontal position. Sutures were placed through the dorsal aspect of the uterine body and uterine horn and the adjacent region of the mesometrium using a simple continuous suture pattern. Results: The uterus of all 5 mares was elevated successfully to a horizontal position. Three of the mares became pregnant the same year, without other treatment, after the procedure. Conclusions: A pendulous, ventrally‐angled uterus can be returned to a normal, horizontal position by imbricating the mesometria, using a laparoscopic technique. Potential relevance: Elevating a ventrally‐angled uterus to a horizontal position may improve egress of uterine debris, thereby improving fertility.  相似文献   

3.
The purpose of this paper is to explain what the ‘Selectadog’ programme is, to emphasize some things it is not, to show what it is for and who benefits, to detail the forms that it is in, to give some indication as to how it works and to relate some of the experiences of using ‘Selectadog’ in the United Kingdom and elsewhere since 1975. ‘Selectadog’ is a programme designed to match up the characteristics of the more popular breeds of dog to the circumstances of potential owners, as identified by means of a questionnaire. Its purpose is to give guidance to people thinking about getting a dog and above all to make them think through the points they should be considering about fitting a new dog into their lives. At best and it is quite a good best, it can give the prospective owner a number of leads and a positive starting point. It also provides a good deal of free advice and information to allow the new owner to begin a prolonged period of responsible pet animal ownership, without putting them off unnecessarily.  相似文献   

4.
摘要:为巩固发展云阳优质柑桔支柱产业,探索诱杀柑桔大实蝇成虫的环保药剂,结果表明,参试的6种药剂防效均达80%以上,绿色防控药剂0.1%阿维菌素果瑞特果实蝇诱杀剂、0.1%阿维菌素糖酒醋液防效分别达98.7%、97.68%,优于敌百虫、乙基多杀菌素、毒死蜱和阿维菌素;食物诱杀药剂防治柑桔大实蝇成虫,应在果园监测到成虫开始取食或羽化出土始期给药,并持续于整个羽化、取食、产卵期,喷洒颗粒液体诱杀效果显著。  相似文献   

5.
We used a linear programming model to estimate the financial returns to a Staphylococcus aureus testing and control program over a 1-year period for a 100-cow herd, with a 8636-kg rolling-herd average. Six tests, which vary in sensitivity from 0.80 to 0.98 and specificity of 0.99, were examined in simulated herds with 10, 20 and 30% prevalence of S. aureus infection. Sensitivity of these results to a range of assumptions regarding rolling-herd average, milk price, somatic cell-count premium, and cost and cure rate of dry treatment were examined to determine the profits from the program. The profits of a control program are most dependent upon prevalence, cell-count premium, and cost of dry treatment. In our simulation for a 100-cow herd, a testing and control program appears to cost less than US$10 per cow per year, and pays for itself within 1 yr, except under the lowest prevalence and most-adverse conditions (low yield, high cost of dry treatment, or low SCC premium).  相似文献   

6.
Poultry transportation coops are rarely washed and have been demonstrated to be a point of cross-contamination of broiler carcasses. Foaming disinfectants and cleaners, commonly used within processing plants, may be used to clean and disinfect poultry transportation coops. In this study, homogenized fecal material was evenly applied to the floors of precleaned broiler transportation coops and allowed to dry. Treatments consisted of a water rinse, a foam additive alone, foaming cleaner, and a disinfectant plus a foam additive. All foaming treatments were applied using a compressed air foam system (2,271 L/min; 600 gal/min), similar to what firefighters would use. A high-pressure water rinse (HPWR) was added prior to or following the treatments to determine whether rinsing prior to product application or rinsing after product application would improve efficacy. Based on our data, a compressed air foam system may be used in combination with a commercially available disinfectant or foam cleaner to reduce aerobic bacteria on the surfaces of commercial broiler transportation coops. Furthermore, the addition of a HPWR did not further reduce the level of aerobic bacteria on broiler transportation coop floors.  相似文献   

7.
Following sudden exposure to extreme cold, a group of 15-week-old pigs exhibited strange nervous signs which included arching the back, a high stepping gait, violent tremors of the whole body and screaming. The animals lowered themselves and once sitting, the tremors and screaming stopped. But if forced to rise, these signs recurred. When the pigs returned to a warmer environment, they rapidly recovered. An acute clinical myopathy caused by a marginal vitamin E deficiency was suspected. Other stress-induced factors, such as circulatory collapse caused by movement from a warm to a cold environment, were also thought to have contributed towards the myopathy.  相似文献   

8.
AIMS: To compare two methods of applying rubber rings to the pedicles of yearling stags to induce analgesia in the antler prior to removal. To compare the application of a rubber ring with that of a lignocaine ring block of the antler pedicle on the efficacy and time course of the analgesia produced in yearling stags.

METHODS: Rubber rings were applied to the pedicles of 36 yearling stags that required velvet antler removal. The standard method, a doubled-over ring expanded and lowered down from the distal end of the antler and released midway down the pedicle, was compared with a cable-tie method on the other pedicle, where a ring was pulled around the pedicle by an electrical cable tie threaded through the ring. Brief electrical stimulation (train-of-four mode) was applied proximal and distal to the ring before, and at regular intervals for 1 hour after, application of the ring to a level that produced an auriculopalpebral reflex response.

In a second experiment, each pair of antlers per yearling stag (n=36) was allocated to one of three pairs of treatments, viz no treatment (control) and the cable-tie method as described above, control and local anaesthesia (a ring block of 2 ml 2% lignocaine per cm pedicle circumference), or the cable-tie method and local anaesthesia. Electrical stimulation (tetanic mode) was applied to each antler approximately 25 mm distal to the pedicle/antler junction before, and at intervals up to 1 hour after, application of treatments at a level required to produce a head/neck avoidance behavioural response.

In a third experiment, the two electrical stimulation protocols used above were directly compared by measuring the response of stags (n=8) to one protocol on each pedicle/antler prior to, and at intervals for 1 hour after, application of a rubber ring. At the end of each treatment in all three experiments, analgesia of the antler was established as a nil behavioural response of the stag to a saw cut to the antler (the ‘nick test’).

RESULTS: For both methods of application of a ring the minimum electrical stimulation required distal to the ring to elicit a reflex response increased from around 16 to 55 mA by 60 minutes. In contrast, the electrical stimulation required proximal to the ring remained low (~17.0 mA) throughout. No stag subjected to either of the methods of application responded to the nick test 60 minutes after application of the ring.

The electrical stimulation required to produce a behavioural response increased very rapidly in stags treated with local anaesthetic and at a slower rate in those treated with the cabletie method but showed no significant increase in control stags. After 4 and 30 minutes, for local anaesthesia and the cable-tie method, respectively, 95% of stags were not responding to 80 mA. A significantly greater proportion of stags with antlers treated with local anaesthetic and the cable-tie method did not respond to the nick test than controls, and there was no significant difference in the frequency of the response between stags with treated antlers.

The minimum current required to produce a response proximal to a rubber ring was slightly higher on average for train-of-four electrical stimulus (mean 18.1 (SD 2.6) mA) than for the tetanic mode (mean 11.9 (SD 2.5) mA). The increase in minimum current required to produce the respective response to stimulation distal to the ring was similar for both methods, although the maximum predicted value (67.4 mA) was lower for train-of-four than for the tetanic mode (84.5 mA). No stag responded to the nick test =60 minutes after application of the ring.

CONCLUSIONS: The cable-tie method was no different from the standard method as a procedure for producing analgesia in the antlers of yearling stags and should be accepted as an appropriate procedure for applying analgesic rings to yearling stags. The analgesia produced in the antlers of yearling stags by rubber rings applied by the cable-tie method to the pedicle was similar to that of a lignocaine ring block, but the time course for the development of analgesia was markedly different. Given that a lignocaine ring block is accepted as an adequate method of pain relief for antler removal, the application of rubber rings followed by a period of =30 minutes after application can be advocated as a viable alternative for pain relief.  相似文献   

9.
Motivation in writing this article stems from many things: a lack of time spent in the veterinary curriculum discussing vaccines, a growing concern(by the general public and the veterinary community) regarding adverse reactions associated with vaccines, and a desire to prevent a recurrence of preventable infectious diseases resulting from a fear-driven cessation of vaccine administration. The objectives of this article are to present a basic review of immunology as related to vaccines, to discuss general guidelines for pediatric vaccines in canine and feline patients,and to offer suggestions as to how we can most positively influence our patients' health from the first visit.  相似文献   

10.
The concept of coping can be used to relate the environmental conditions provided for livestock to their responses--their productivity and their welfare. Pigs are "ecological generalists" and hence are "designed" to cope with a wide variety of environmental conditions. They, however, show clear limits to their adaptability both in terms of the space they require and the pen materials they can endure without injury. Even where they adapt to a wide range of conditions, there often is a particular environment that gives optimum performance. Examples of temperature requirements and feeding facilities are discussed. The process of coping is shown to impose a biological "cost" in some instances and, although a pig has adapted to a specific environment, questions still remain concerning whether keeping a pig in that environment is justifiable.  相似文献   

11.
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   

12.
In commercial livestock populations, QTL detection methods often use existing half-sib family structures and ignore additional relationships within and between families. We reanalyzed the data from a large QTL confirmation experiment with 10 pig lines and 10 chromosome regions using identity-by-descent (IBD) scores and variance component analyses. The IBD scores were obtained using a Monte Carlo Markov Chain method, as implemented in the LOKI software, and were used to model a putative QTL in a mixed animal model. The analyses revealed 61 QTL at a nominal 5% level (out of 650 tests). Twenty-seven QTL mapped to areas where QTL have been reported, and eight of these exceeded the threshold to claim confirmed linkage (P < 0.01). Forty-two of the putative QTL were detected previously using half-sib analyses, whereas 46 QTL previously identified by half-sib analyses could not be confirmed using the variance component approach. Some of the differences could be traced back to the underlying assumptions between the two methods. Using a deterministic approach to estimate IBD scores on a subset of the data gave very similar results to LOKI. We have demonstrated the feasibility of applying variance component QTL analysis to a large amount of data, equivalent to a genome scan. In many situations, the deterministic IBD approach offers a fast alternative to LOKI.  相似文献   

13.
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   

14.
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   

15.
A study was undertaken to determine if it might be possible to prepare tissue sections on slides without the use of paraffin embedding, microtome sectioning, or cryostat sectioning which involve equipment and training not always available to scholars or professionals wishing to examine tissue microscopically. After evaluating many different reagents, cutting instruments and solid supports, we developed a method involving application of super glue to a slide, adhering a section of tissue to it, cutting the tissue with a disposable microtome blade, staining the tissue and removing the superglue with a commercially available product. The sections are similar to those sectioned on a microtome, but do not at this time equal their quality. However, histoarchitecture is preserved and individual cell morphology is usually good. We conclude that this is a viable method for preparing histology sections without the use of a microtome or cryostat, something long thought impossible. We have dubbed the method 'RAMP' (Rapid Adhesive-Mediated Procedure).  相似文献   

16.
Salmonellosis in calves has economic and welfare implications, and serves as a potential source of human infections. Our objectives were to assess the risk of Salmonella spread following its introduction into a herd of pre-weaned calves and to evaluate the efficacy of control strategies to prevent and control outbreaks. To meet these objectives, we developed a model of Salmonella transmission within a pre-weaned group of calves based on a well documented outbreak of salmonellosis in a calf-raising operation and other literature. Intervention scenarios were evaluated in both deterministic and stochastic versions of the model. While the basic reproduction number (R0) was estimated to be 2.4, simulation analysis showed that more than 60% of the invasions failed after the introduction of a single index case. With repeated introduction of index cases, the probability of Salmonella spread was close to 1, and the tested control strategies were insufficient to prevent transmission within the group. The most effective strategies to control ongoing outbreaks were to completely close the rearing operation to incoming calves, to increase the proportion of admitted calves that were immunized (>75%), and to assign personnel and equipment to groups of calves.  相似文献   

17.
In the present study we compared the immunological reactions between Rhipicephalus sanguineus tick-infested susceptible (dogs and mice) and tick-resistant hosts (guinea pigs), elucidating some of the components of efficient protective responses against ticks. We found that T-cells from guinea pigs infested with adult ticks proliferate vigorously in the presence of concanavalin A (ConA), whereas ConA-induced cell proliferation of tick-infested mice and dogs was significantly decreased at 43.1 and 94.0%, respectively, compared to non-infested controls. Moreover, cells from mice and dogs submitted to one or three successive infestations did not exhibit a T-cell proliferative response to tick antigens, whilst cells from thrice tick-infested guinea pigs, when cultured with either a tick extract or tick saliva, displayed a significant increase in cell proliferation. Also, we evaluated the response of tick-infested mice to a cutaneous hypersensitivity test induced by a tick extract. Tick-infested mice developed a significant immediate reaction, whereby a 29.9% increase in the footpad thickness was observed. No delayed-type hypersensitivity (DTH) reaction was detected. Finally, the differential cell count at the tick attachment site in repeatedly infested mice exhibited a 6.6- and 4.1-fold increase in the percentage of eosinophils and neutrophils, respectively, compared to non-infested animals, while a decrease of 77.0-40.9 in the percentage of mononuclear cells was observed. The results of the cutaneous hypersensitivity test and the cellular counts at the tick feeding site for mice support the view that tick-infested mice develop an immune response to R. sanguineus ticks very similar to dogs, the natural host of this species of tick, but very different from guinea pigs (resistant host), which develop a DTH reaction in addition to a basophil and mononuclear cell infiltration at the tick-attachment site. In conclusion, saliva introduced during tick infestations reduces the ability of a susceptible animal host to respond to tick antigens that could stimulate a protective immune response. As a consequence, the animals present a lack of DTH response and disturbed cellular migration to tick feeding site, which can represent a deficient response against ticks.  相似文献   

18.
Canine microsatellites, comprising one to four base pair repeated sequences, were identified as part of a project to generate a genetic linkage map of the dog. They have been used to assign parentage in a range of doubtful paternity cases, for example, all the pups in a litter from a bitch mated on different days to two different stud dogs were identified by DNA analysis to come from one dog only. DNA typing in another case was able to exclude a male dog as the father of a litter. DNA analysis can be of relevance by allowing pedigree dogs, which would have previously been excluded on the basis of unknown paternity, to be registered with the appropriate kennel club.  相似文献   

19.
Opportunities and change continue to occur at an accelerating rate. The exotic Newcastle disease (END) crisis in the traditional commercial industry led to a related problem for game bird producers due to confusion in defining a game bird, which is also a commercial venture. Time spent planning rather than reacting to situations is often a luxury but must be moved to a higher priority. One example is the Triennial Extension Workshop, which is proposed to become a biennial event. We continue to develop and implement innovative programs based on relevance to animal agriculture and societal requirements. As a team, we have achieved an excellent synergy and impressive results through our cooperation and networking. A special award is provided to an extension person each year to ensure contributions are recognized that might otherwise be overlooked. The Texture Technologies Corporation Support Personnel Award is new this year and recognizes the essential contributions of farm, laboratory, and other personnel. Also, the American Poultry Historical Society (APHS) continues to recognize career contributions to the poultry system through the Hall of Fame. As always, anyone wishing to be part of program planning and development is welcome. If you are not called, take the initiative and volunteer.  相似文献   

20.
We used a linear programming model to estimate the financial returns to a Staphylococcus aureus testing and control program over a 1-year period for a 100-cow herd, with a 8636kg rolling-herd average. Six tests, which vary in sensitivity from 0.80 to 0.98 and specificity of 0.99, were examined in simulated herds with 10, 20, and 30% prevalence of S. aureus infection. Sensitivity of these results to a range of assumptions regarding rolling-herd average, milk price, somatic cell-count premium, and cost and cure rate of dry treatment were examined to determine the profits from the program. The profits of a control program are most dependent upon prevalence and cell-count premium. In our simulation for a 100-cow herd, a testing and control program results in a profit ranging from US$1.50 to US$20 per cow per year, except under the lowest prevalence and most-adverse conditions (low yield or low SCC premium).  相似文献   

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