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Husbandry Practices (husbandry + practice)
Selected AbstractsAffective and Adrenocorticotrophic Responses to Photoperiod in Wistar RatsJOURNAL OF NEUROENDOCRINOLOGY, Issue 2 2008B. J. Prendergast The present study tested the hypothesis that seasonal intervals of exposure to modest changes in photoperiod, typical of those experienced by humans living in temperate latitudes (10,14 h light/day), engage changes in emotional behaviour of Wistar rats, a commonly-used animal model for investigations of affective physiology. Short day lengths (, 12 h light/day) induced behavioural despair in a forced-swim test, exploratory anxiety in an open field arena, and anhedonia in a two-bottle sucrose preference task, relative to longer day lengths. Plasma adrenocorticotrophic hormone was lower in short-day relative to long-day rats, but testosterone and corticosterone concentrations were comparable across treatments. In common with animals that engage reproductive responses to day length, reproductively nonresponsive mammals such as Wistar rats exhibit changes in affective state following small changes in day length. Wistar rats may provide an animal model for the study of seasonal mood regulation because the neuroendocrine, depressive, anxious and anhedonic responses of Wistar rats to short days bear similarities to those observed in some human populations. Standard laboratory husbandry practices (exposure to a 12 : 12 h light/dark cycle) may inadvertently deliver a chronic background depressive and anxiogenic stimulus. [source] Terrestrial carnivores and human food production: impact and managementMAMMAL REVIEW, Issue 2-3 2008PHILIP J. BAKER ABSTRACT 1The production of food for human consumption has led to an historical and global conflict with terrestrial carnivores, which in turn has resulted in the extinction or extirpation of many species, although some have benefited. At present, carnivores affect food production by: (i) killing human producers; killing and/or eating (ii) fish/shellfish; (iii) game/wildfowl; (iv) livestock; (v) damaging crops; (vi) transmitting diseases; and (vii) through trophic interactions with other species in agricultural landscapes. Conversely, carnivores can themselves be a source of dietary protein (bushmeat). 2Globally, the major areas of conflict are predation on livestock and the transmission of rabies. At a broad scale, livestock predation is a customary problem where predators are present and has been quantified for a broad range of carnivore species, although the veracity of these estimates is equivocal. Typically, but not always, losses are small relative to the numbers held, but can be a significant proportion of total livestock mortality. Losses experienced by producers are often highly variable, indicating that factors such as husbandry practices and predator behaviour may significantly affect the relative vulnerability of properties in the wider landscape. Within livestock herds, juvenile animals are particularly vulnerable. 3Proactive and reactive culling are widely practised as a means to limit predation on livestock and game. Historic changes in species' distributions and abundance illustrate that culling programmes can be very effective at reducing predator density, although such substantive impacts are generally considered undesirable for native predators. However, despite their prevalence, the effectiveness, efficiency and the benefit:cost ratio of culling programmes have been poorly studied. 4A wide range of non-lethal methods to limit predation has been studied. However, many of these have their practical limitations and are unlikely to be widely applicable. 5Lethal approaches are likely to dominate the management of terrestrial carnivores for the foreseeable future, but animal welfare considerations are increasingly likely to influence management strategies. The adoption of non-lethal approaches will depend upon proof of their effectiveness and the willingness of stakeholders to implement them, and, in some cases, appropriate licensing and legislation. 6Overall, it is apparent that we still understand relatively little about the importance of factors affecting predation on livestock and how to manage this conflict effectively. We consider the following avenues of research to be essential: (i) quantified assessments of the loss of viable livestock; (ii) landscape-level studies of contiguous properties to quantify losses associated with variables such as different husbandry practices; (iii) replicated experimental manipulations to identify the relative benefit of particular management practices, incorporating (iv) techniques to identify individual predators killing stock; and (v) economic analyses of different management approaches to quantify optimal production strategies. [source] Development and validation of a simulation model for blowfly strike of sheepMEDICAL AND VETERINARY ENTOMOLOGY, Issue 4 2002R. Wall Abstract A comprehensive simulation model for sheep blowfly strike due to Lucilia sericata (Meigen) (Diptera: Calliphoridae), which builds on previously published versions but also incorporates important new empirical data, is used to explain patterns of lamb and ewe strike recorded on 370 farms in south-west, south-east and central England and Wales. The model is able to explain a significant percentage of the variance in lamb strike incidence in all four regions, and ewe strike in three of the four regions. The model is able to predict the start of seasonal blowfly strike within one week in three of the four regions for both ewes and lambs, and within 3 weeks in the fourth region. It is concluded that the accuracy of the model will allow it to be used to assess the likely efficacy of new control techniques and the effects of changes in existing husbandry practices on strike incidence. The model could also be used to give sheep farmers advance warning of approaching strike problems. However, the ability to forecast future strike patterns is dependent on the accuracy of the weather projections; the more long-term the forecast, the more approximate the prediction is likely to be. When applied on a regional basis, model forecasts indicate expected average patterns of strike incidence and may not therefore be appropriate for individual farmers whose husbandry practices differ substantially from the average. [source] Xenotransplantation, Xenogeneic Infections, Biotechnology, and Public HealthMOUNT SINAI JOURNAL OF MEDICINE: A JOURNAL OF PERSONALIZED AND TRANSLATIONAL MEDICINE, Issue 5 2009Louisa E. Chapman MD Abstract Xenotransplantation is the attempt to use living biological material from nonhuman animal species in humans for therapeutic purposes. Clinical trials and preclinical studies have suggested that living cells and tissue from other species have the potential to be used in humans to ameliorate disease. However, the potential for successful xenotransplantation to cure human disease is coupled with the risk that therapeutic use of living nonhuman cells in humans may also serve to introduce xenogeneic infections of unpredictable significance. Animal husbandry practices and xenotransplantation product preparation may eliminate most exogenous infectious agents prior to transplantation. However, endogenous retroviruses are present in the genomes of all mammalian cells, have an inadequately defined ability to infect human cells, and have generated public health concern. The history of xenotransplantation, the implications for public health, the global consensus on public safeguards necessary to accompany clinical trials, and the future direction of xenotransplantation are discussed in the context of public health. Mt Sinai J Med 76:435,441, 2009. © 2009 Mount Sinai School of Medicine [source] Effects of human,carnivore conflict on tiger (Panthera tigris) and prey populations in Lao PDRANIMAL CONSERVATION, Issue 4 2006A. Johnson Abstract Unique to South-east Asia, Lao People's Democratic Republic contains extensive habitat for tigers and their prey within a multiple-use protected area system covering 13% of the country. Although human population density is the lowest in the region, the impact of human occurrence in protected areas on tiger Panthera tigris and prey populations was unknown. We examined the effects of human,carnivore conflict on tiger and prey abundance and distribution in the Nam Et-Phou Louey National Protected Area on the Lao,Vietnam border. We conducted intensive camera-trap sampling of large carnivores and prey at varying levels of human population and monitored carnivore depredation of livestock across the protected area. The relative abundance of large ungulates was low throughout whereas that of small prey was significantly higher where human density was lower. The estimated tiger density for the sample area ranged from 0.2 to 0.7 per 100 km2. Tiger abundance was significantly lower where human population and disturbance were greater. Three factors, commercial poaching associated with livestock grazing followed by prey depletion and competition between large carnivores, are likely responsible for tiger abundance and distribution. Maintaining tigers in the country's protected areas will be dependent on the spatial separation of large carnivores and humans by modifying livestock husbandry practices and enforcing zoning. [source] Effects of crop debris and cultivations on the development of eyespot of wheat caused by Oculimacula spp.ANNALS OF APPLIED BIOLOGY, Issue 3 2010J.F. Jenkyn Results from a series of crop sequence and single-year experiments that tested different straw and cultivation treatments in a total of 11 site,season combinations confirmed previous evidence that the development of eyespot disease in cereals can be decreased by debris in the seed bed even if that debris includes eyespot-infected stem bases, which are the principal sources of primary inoculum. Two of the experiments, which followed non-cereal break crops and tested the effects of crop debris applied after ploughing or tining on eyespot in winter wheat that was artificially inoculated with Oculimacula spp., provided convincing evidence that the effects can be attributed to the debris per se, and not to any associated husbandry practices. There were often larger effects on disease in summer than in spring or on severity than on incidence suggesting that the effects of debris cannot be explained solely by effects on inoculum or initial infection, and that debris has a disease-suppressive effect. [source] Investigation of the temporal effects of spawning season and maternal and paternal differences on egg quality in Atlantic cod Gadus morhua L. broodstockAQUACULTURE RESEARCH, Issue 14 2009Dounia Hamoutene Abstract A better understanding of the parameters affecting egg quality and larval survival is of importance for continued development of cod broodstock and efficient husbandry practices. Decision tree analysis (DTA) was applied to analyse 3 years of egg quality data in an effort to extract the most important variables (i.e. predictors) in explaining differences in egg quality. The effect of three predictors (spawning time, maternal and paternal differences) has been studied on early cleavage pattern parameters, egg diameters, fertilization and hatching rates and has shown that females are the dominant variable and that time has a limited and inconsistent impact on the data. When using maternal, paternal differences and batch number (instead of spawning time) as predictors, the results confirm that no particular relationship is found between batch order (i.e. order in time) and egg quality. Moreover, batches with a higher egg quality show a consistency in the parameters assessed (i.e. batches with higher rates of normality in any parameter tend to be normal for other parameters). This is confirmed by the significant correlations found between cleavage parameters. Our results highlight that spawning time is of less importance than female parent contribution in ensuring high rates of fertilization and larval hatch, and maximizing general egg quality. 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