942 resultados para Vaccination of animals.


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Beds of nonattached coralline algae (maerl or rhodoliths) are widespread and considered relatively species rich. This habitat is generally found in areas where there is chronic physical disturbance such that maerl thalli are frequently moved. Little is known, however, about how natural disturbance regimes affect the species associated with maerl. This study compared the richness, animal abundance, and algal biomass of maerl-associated species over a two-year period in a wave-disturbed bed and a sheltered maerl bed. Changes in associated species over time were assessed for departures from a neutral model in which the dissimilarity between samples reflects random sampling from a common species pool. Algal biomass and species richness at the wave-exposed site and on stabilized maerl at the sheltered site were reduced at times of higher wind speeds. The changes in species richness were not distinguishable from a neutral model, implying that algal species were added at random to the assemblage as the level of disturbance lessened. Results for animal species were more mixed. Although mobile species were less abundant during windy periods at the exposed site, both neutral and non-neutral patterns were evident in the assemblages. Artificial stabilization of maerl had inconsistent effects on the richness of animals but always resulted in more attached algal species. While the results show that the response of a community to disturbance can be neutral, the domain of neutral changes in communities may be relatively small. Alongside non-neutral responses to natural disturbance, artificial stabilization always resulted in an assemblage that was more distinct than would be expected under random sampling from a common pool. Community responses to stabilization treatments did not consistently follow the predictions of the dynamic equilibrium model, the intermediate disturbance model, or a facilitation model. These inconsistencies may reflect site-specific variation in both the disturbance regime and the adjacent habitats that provide source populations for many of the species found associated with maerl.

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The detection of illicit growth promoter use during meat production within the European Union is reliant on residue testing which is a limiting factor on the number of animals which can be tested and consequently compromises the efficacy of testing procedures. The present study examined a novel detection strategy based on the profiling of plasma component concentrations in response to growth promoter administrations. Calves subjected to nortestosterone decanoate, 17 beta-oestradiol benzoate and dexamethasone were found to have altered urea, aminoterminal propeptide of type III procollagen and sex hormone binding globulin profiles in response to treatments. These findings demonstrate the potential of using the identification of perturbed profiles within a panel of biomarkers which cover a spectrum of biological activity to reveal growth promoter abuse.

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Previous studies have shown that glycation of insulin occurs in pancreatic beta -cells under conditions of hyperglycaemia and that the site of glycation is the N-terminal Phe(1) of the insulin B-chain. To enable evaluation of glycated insulin in diabetes, specific antibodies were raised in rabbits and guinea-pigs by using two synthetic peptides (A: Phe-Val-Asn-Gln-His-Leu-Cys-Tyr, and B: Phe-Val-Asn-Gln-His-Leu-Tyr-Lys) modified by N-terminal glycation and corresponding closely to the N-terminal sequence of the glycated human insulin B-chain. For immunization, the glycated peptides were conjugated either to keyhole limper haemocyanin or ovalbumin using glutaraldehyde, m-maleimidobenzoyl-N-hydroxysuccinimide ester or 1-ethyl-3-(3-dimethylamino propyl) carbodiimide hydrochloride. Antibody titration curves, obtained using I-125-tyrosylated tracer prepared from glycated peptide A, revealed high-titre antisera in five groups of animals immunized for 8-28 weeks. The highest titres were observed in rabbits and guinea-pigs immunized with peptide B coupled to ovalbumin using glutaraldehyde. Under radioimmunoassay conditions, these antisera exhibited effective dose (median) (ED50) values for glycated insulin of 0.3-15 ng/ml and 0.9-2.5 ng/ml respectively, with negligible cross-reactivity against insulin or other islet peptides. The degree of cross-reaction with glycated proinsulin was approximately 50%. Glycated insulin in plasma of control and hydrocortisone-treated diabetic rats measured using rabbit 3 antiserum (1:10 000 dilution; sensitivity

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While the incorporation of mathematical and engineering methods has greatly advanced in other areas of the life sciences, they have been under-utilized in the field of animal welfare. Exceptions are beginning to emerge and share a common motivation to quantify 'hidden' aspects in the structure of the behaviour of an individual, or group of animals. Such analyses have the potential to quantify behavioural markers of pain and stress and quantify abnormal behaviour objectively. This review seeks to explore the scope of such analytical methods as behavioural indicators of welfare. We outline four classes of analyses that can be used to quantify aspects of behavioural organization. The underlying principles, possible applications and limitations are described for: fractal analysis, temporal methods, social network analysis, and agent-based modelling and simulation. We hope to encourage further application of analyses of behavioural organization by highlighting potential applications in the assessment of animal welfare, and increasing awareness of the scope for the development of new mathematical methods in this area.

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The welfare of farm animals is a policy area that has increased greatly in importance in recent years. When deciding whether a proposed policy should be implemented, it can be useful for policymakers to compare the costs of the proposed improvement with the perceived benefits. The costs are relatively straightforward to calculate but little is known about the benefits. The Contingent Valuation Method (CVM), a direct survey-based method, can be used to shed some light on this. This approach elicits the willingness-to-pay (WTP) for the provision of some public good or service. This paper reports the results of a contingent valuation study of the value of welfare improvements for growing pigs. Attitudes and opinions with regard to form animal welfare are explored and WTP elicited for various pig welfare improvements including increases in space allowance, environmental enrichment and research into improved pig housing design. The results reveal a positive WTP for these improvements. However, it is also noteworthy that a significant proportion of the general public is willing to pay nothing for these improvements. Overall, the study illustrates the usefulness of the CVM approach as a tool for policymakers in assessing the merits of possible policy initiatives affecting the welfare of animals.

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PURPOSE: Animal models are important for pre-clinical assessment of novel therapies in metastatic bladder cancer. The F344/AY-27 model involves orthotopic colonisation with AY-27 tumour cells which are syngeneic to F344 rats. One disadvantage of the model is the unknown status of colonisation between instillation and sacrifice. Non-invasive optical imaging using red fluorescence reporters could potentially detect tumours in situ and would also reduce the number of animals required for each experiment.

MATERIALS AND METHODS: AY-27 cells were stably transfected with either pDsRed2-N1 or pcDNA3.1tdTomato. The intensity and stability of fluorescence in the resultant AY-27/DsRed2-N1 and AY-27/tdTomato stable cell lines were compared using Xenogen IVIS®200 and Olympus IX51 systems.

RESULTS: AY-27/tdTomato fluorescence intensity was 60-fold brighter than AY-27/DsRed2-N1 and was sustained in AY-27/tdTomato cells following freezing and six subsequent sub-cultures. After sub-cutaneous injection, fluorescence intensity from AY-27/tdTomato cells was threefold stronger than that detected from AY-27/DsRed2-N1 cells. IVIS®200 detected fluorescence from AY-27/tdTomato and AY-27/DsRed2-N1 cells colonising resected and exteriorised bladders, respectively. However, the deep-seated position of the bladder precluded in vivo imaging. Characteristics of AY-27/tdTomato cells in vitro and in tumours colonising F344 rats resembled those of parental AY-27 cells. Tumour transformation was observed in the bladders colonised with AY-27/DsRed2-N1 cells.

CONCLUSIONS: In vivo whole-body imaging of internal red fluorescent animal tumours should use pcDNA3.1tdTomato rather than pDsRed2-N1. Optical imaging of deep-seated organs in larger animals remains a challenge which may require proteins with brighter red or far-red fluorescence and/or alternative approaches.

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The issue of inherited disorders in pedigree dogs is not a recent phenomenon and reports of suspected genetic defects associated with breeding practices date back to Charles Darwin's time. In recent years, much information on the array of inherited defects has been assimilated and the true extent of the problem has come to light. Historically, the direction of research funding in the field of canine genetic disease has been largely influenced by the potential transferability of findings to human medicine, economic benefit and importance of dogs for working purposes. More recently, the argument for a more canine welfare-orientated approach has been made, targeting research efforts at the alleviation of the most suffering in the greatest number of animals.

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The everyday lives of many farm workers in eighteenth- and early nineteenth-century England were intricately and often intimately bound with the lives of animals, the ebb and flow of human life being inseparable from that of animal life. Farmyards, fields, folds as well as barns and stables were all spaces where animals transcended being the mere instruments of capital to instead being obvious co-constituents of the rhythms of existence. Living and working in such close proximity meant that the ‘species barrier’ was crossed and intimacies developed in everyday agricultural practices. Still, the relationship was based upon, if not reducible to, the workings of capital: the animal enrolled as a form of embodied capital, the labourer engaged by the farmer to act upon the animal. And in such relationships intimacies are mirrored by violences: the keeping captive, slaughter, and – occasionally – abuse. In this formative period in which the discourses and policies that continue to inform animal welfare were first formulated, the declining economic and material fortunes of farm workers when juxtaposed to farm animals’ fortune as increasingly ‘cosseted capital’ gave a particular charge to these abuses. Farm animals, and especially horses and cattle, so it is shown, were subjected to a series of violences. Many cases of animal maiming parodied tenderness in their brutality, whilst other attacks on the sexual organs of animals represented complex statements about the ways in which agrarian capitalism regulated all culture. Analysing the changing relationship between humans and animals therefore also helps us to better understand how capitalism mediates – and is mediated by – the non-human as well as the human, and how it defines cultural relations.

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Reproductive performance in the high-yielding dairy cow has severely decreased in the last 40 yr. The aim of this study was to compare the effectiveness of 4 nutritional strategies in improving the reproductive performance of high-yielding dairy cows. It was hypothesized that offering cows a high-starch ration in early lactation would enhance the onset of luteal activity, and that decreasing the severity of negative energy balance in the early postcalving period would improve reproductive parameters. Nutritional regimens aimed at improving fertility were applied to 96 Holstein-Friesian dairy animals. Upon calving, animals were allocated in a balanced manner to one of 4 dietary treatments. Primiparous animals were balanced according to live weight, body condition score and calving date. Multiparous animals were balanced according to parity, previous lactation milk yield, liveweight, body condition score and calving date. Treatment 1 was based on an industry best practice diet (control) to contain 170 g of crude protein/kg of dry matter. Treatment 2 was an individual cow feeding strategy, whereby the energy balance (EB) of individual animals was managed so as to achieve a predetermined target daily EB profile (+/- 10 MJ/d). Treatment 3 was a high-starch/high-fat combination treatment, whereby an insulinogenic (high-starch) diet was offered in early lactation to encourage cyclicity and followed by a lipogenic (low-starch, high-fat) diet to promote embryo development. Treatment 4 was a low-protein diet, containing 140 g of crude protein/kg of dry matter, supplemented with protected methionine at an inclusion level of 40 g per animal per day. The nutritional strategies implemented in this study had no statistically significant effects on cow fertility measures, which included the onset of luteal activity, conception rate, in-calf rate, and the incidence of atypical cycles. The individual cow feeding strategy improved EB in early lactation but had no benefit on conception rate to first insemination. However, conception rate to second insemination, 100-d pregnancy rate (from the commencement of breeding), and overall pregnancy rate tended to be higher in this group. The high-starch/high-fat treatment tended to decrease the proportion of delayed ovulations and increase the proportion of animals cycling by d 50 postcalving. Animals that failed to conceive to first insemination had a significantly longer luteal phase in the first cycle postpartum and a longer inter-ovulatory interval in the second cycle postpartum. With regards to estrous behavior, results indicate that as the size of the sexually active group increased, the intensity of estrus and the expression of mounting or attempting to mount another cow also increased. Furthermore, cows that became pregnant displayed more intense estrous behavior than cows that failed to become pregnant.

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This study investigates how habitat variation affects sett density, the number of animals per social group and group territory size in the badger (Meles meles). Identical methods were applied in three habitat types: lowland parkland with mixed woodland, pastoral farmland and upland rough pasture with moorland, representing areas of presumed good, medium and poor badger habitat, respectively. Contiguous main setts were identified and bait-marking was used to estimate territory size. Group size was estimated by direct enumeration. Variation in sett density, group size and territory size supported the hypothesis that badger group and territory size are influenced by habitat type. This was further supported by analyses of data from other studies in the British Isles. The implications for badger spatial ecology, badger survey techniques and the badger's role in the epidemiology of TB are discussed.

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Chronic lung infection by opportunistic pathogens, such as Pseudomonas aeruginosa and members of the Burkholderia cepacia complex, is a major cause of morbidity and mortality in patients with cystic fibrosis. Outer membrane proteins (OMPs) of gram-negative bacteria are promising vaccine antigen candidates. In this study, we evaluated the immunogenicity, protection, and cross-protection conferred by intranasal vaccination of mice with OMPs from B. multivorans plus the mucosal adjuvant adamantylamide dipeptide (AdDP). Robust mucosal and systemic immune responses were stimulated by vaccination of naive animals with OMPs from B. multivorans and B. cenocepacia plus AdDP. Using a mouse model of chronic pulmonary infection, we observed enhanced clearance of B. multivorans from the lungs of vaccinated animals, which correlated with OMP-specific secretory immunoglobulin A responses. Furthermore, OMP-immunized mice showed rapid resolution of the pulmonary infection with virtually no lung pathology after bacterial challenge with B. multivorans. In addition, we demonstrated that administration of B. multivorans OMP vaccine conferred protection against B. cenocepacia challenge in this mouse infection model, suggesting that OMPs provide cross-protection against the B. cepacia complex. Therefore, we concluded that mucosal immunity to B. multivorans elicited by intranasal vaccination with OMPs plus AdDP could prevent early steps of colonization and infection with B. multivorans and also ameliorate lung tissue damage, while eliciting cross-protection against B. cenocepacia. These results support the notion that therapies leading to increased mucosal immunity in the airways may help patients with cystic fibrosis.

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Saxitoxin (STX) is a low molecular weight neurotoxin mainly produced by certain marine dinoflagellates that, along with its family of similarly related paralytic shellfish toxins, may cause the potentially fatal intoxication known as paralytic shellfish poisoning. Illness and fatality rates are low due to the effective monitoring programs that determine when toxins exceed the established regulatory action level and effectuate shellfish harvesting closures accordingly. Such monitoring programs rely on the ability to rapidly screen large volumes of samples. Many of the screening assays currently available employ antibodies or live animals. This research focused on developing an analytical recognition element that would eliminate the challenges associated with the limited availability of antibodies and the use of animals. Here we report the discovery of a DNA aptamer that targets STX. Concentration-dependent and selective binding of the aptamer to STX was determined using a surface plasmon resonance sensor. Not only does this work represent the first reported aptamer to STX, but also the first aptamer to any marine biotoxin. A novel strategy of using a toxin-protein conjugate for DNA aptamer selection was successfully implemented to overcome the challenges associated with aptamer selection to small molecules. Taking advantage of such an approach could lead to increased diversity and accessibility of aptamers to low molecular weight toxins, which could then be incorporated as analytical recognition elements in diagnostic assays for foodborne toxin detection. The selected STX aptamer sequence is provided here, making it available to any investigator for use in assay development for the detection of STX.

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Broadcast spawning invertebrates that live in shallow, high-energy coastal habitats are subjected to oscillatory water motion that creates unsteady flow fields above the surface of animals. The frequency of the oscillatory fluctuations is driven by the wave period, which will influence the stability of local flow structures and may affect fertilization processes. Using an oscillatory water tunnel, we quantified the percentage of eggs fertilized on or near spawning green sea urchins, Strongylocentrotus droebachiensis. Eggs were sampled in the water column, wake eddy, substratum and aboral surface under a range of different periods (T = 4.5 – 12.7 s) and velocities of oscillatory flow. The root-mean-square wave velocity (rms(uw)) was a good predictor of fertilization in oscillatory flow, although the root-mean-square of total velocity (rms(u)), which incorporates all the components of flow (current, wave and turbulence), also provided significant predictions. The percentage of eggs fertilized varied between 50 – 85% at low flows (rms(uw) < 0.02 m s-1), depending on the location sampled, but declined to below 10% for most locations at higher rms(uw). The water column was an important location for fertilization with a relative contribution greater than that of the aboral surface, especially at medium and high rms(uw) categories. We conclude that gametes can be successfully fertilized on or near the parent under a range of oscillatory flow conditions.

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The absolute volume of Weibel-Palade (WP) bodies, the storage organelles of von Willebrand factor (vWF), was estimated by a stereological method in a known volume of central retina from normal and 5-year diabetic dogs. The results showed that the volume of WP bodies present in the endothelium of the retinal vasculature varies with blood vessel type and in diabetes. In both diabetic and normal dogs the endothelium of the retinal veins contained a higher volume of WP bodies than that of the retinal arteries. In dogs which had been diabetic for a duration of 5 years the volume of WP bodies present in the endothelium of retinal veins was significantly greater than in the endothelium of veins from the control animals. However, there was no significant difference in the volume of WP bodies present in the endothelium of retinal arteries or capillaries between the two groups of animals.

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The clinical impression that pre-existing diabetes exacerbates radiation injury to the retinal vasculature was studied in STZ diabetic rats. Half of 2 groups of streptozotocin (STZ)-induced diabetic rats and 1 group of normal animals had their right eyes irradiated with 1000 cGy of 90 KVP x-rays. The prevalence of acellular capillaries in trypsin digests of the retinal vasculature was quantified for each of the 6 groups of animals at 6.5 months post-irradiation. The prevalence of acellular capillaries in both non-irradiated diabetic groups was significantly higher than in controls while the irradiated animals in each of the three main categories showed a statistically significant increase compared to their non-irradiated equivalents. However, the net increase in acellular capillaries following irradiation was much greater in rats with an 8 month term of pre-existing diabetes (180%) than in those which had only been diabetic for 3 months (36%). The results of this study suggest a synergistic relationship between pre-existing diabetes and ionising radiation in the development of retinal vasculopathy, and that the potentiation of the vascular damage is dependent on the duration of diabetes prior to radiation exposure.