To send content items to your account,
please confirm that you agree to abide by our usage policies.
If this is the first time you use this feature, you will be asked to authorise Cambridge Core to connect with your account.
Find out more about sending content to .
To send content items to your Kindle, first ensure email@example.com
is added to your Approved Personal Document E-mail List under your Personal Document Settings
on the Manage Your Content and Devices page of your Amazon account. Then enter the ‘name’ part
of your Kindle email address below.
Find out more about sending to your Kindle.
Note you can select to send to either the @free.kindle.com or @kindle.com variations.
‘@free.kindle.com’ emails are free but can only be sent to your device when it is connected to wi-fi.
‘@kindle.com’ emails can be delivered even when you are not connected to wi-fi, but note that service fees apply.
Introduction: Acute aortic syndrome (AAS) is a time sensitive aortic catastrophe that is often misdiagnosed. There are currently no Canadian guidelines to aid in diagnosis. Our goal was to adapt the existing American Heart Association (AHA) and European Society of Cardiology (ESC) diagnostic algorithms for AAS into a Canadian evidence based best practices algorithm targeted for emergency medicine physicians. Methods: We chose to adapt existing high-quality clinical practice guidelines (CPG) previously developed by the AHA/ESC using the GRADE ADOLOPMENT approach. We created a National Advisory Committee consisting of 21 members from across Canada including academic, community and remote/rural emergency physicians/nurses, cardiothoracic and cardiovascular surgeons, cardiac anesthesiologists, critical care physicians, cardiologist, radiologists and patient representatives. The Advisory Committee communicated through multiple teleconference meetings, emails and a one-day in person meeting. The panel prioritized questions and outcomes, using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to assess evidence and make recommendations. The algorithm was prepared and revised through feedback and discussions and through an iterative process until consensus was achieved. Results: The diagnostic algorithm is comprised of an updated pre test probability assessment tool with further testing recommendations based on risk level. The updated tool incorporates likelihood of an alternative diagnosis and point of care ultrasound. The final best practice diagnostic algorithm defined risk levels as Low (0.5% no further testing), Moderate (0.6-5% further testing required) and High ( >5% computed tomography, magnetic resonance imaging, trans esophageal echocardiography). During the consensus and feedback processes, we addressed a number of issues and concerns. D-dimer can be used to reduce probability of AAS in an intermediate risk group, but should not be used in a low or high-risk group. Ultrasound was incorporated as a bedside clinical examination option in pre test probability assessment for aortic insufficiency, abdominal/thoracic aortic aneurysms. Conclusion: We have created the first Canadian best practice diagnostic algorithm for AAS. We hope this diagnostic algorithm will standardize and improve diagnosis of AAS in all emergency departments across Canada.
Changes in body condition score and other linear type traits can be indicative of changes in body energy balance in dairy cattle (Coffey et al., 2003). As an animal proceeds through her lactation it is expected that body shape and fatness levels will change both with peaks and troughs of lactation as well as changes as the animal grows and matures. Wall et al. (2005) showed that udder support (US) was correlated to fertility; cows with weaker udders had poorer fertility. If there are differences between animals in terms of how their udders grow and mature across the first lactation, this could be indicative of health and fertility problems later in life. The aim of this study was to examine how type traits recorded in the national dairy population change over the first lactation and if there is a difference between sires in the type profiles of their daughters.
Energy balance is often considered to be a major factor in the onset of dairy cow reproductive activity in early lactation. The relationships between various aspects of energy balance (EB) and the day of first heat (DFH) are weak when analysed with the mixed generalised linear model approach (e.g. Butler et al., 1981). This is understandable since DFH may not respond to the additivity of the factors which influence it but may require various states to be reached together before the expression of heat occurs. This study investigates a number of factors which may combine to influence DFH to see which combinations appear to be critical for first heat to occur. The aim of this study was to see if an alternative approach to investigating the link between energy balance and day of first heat would provide a stronger relationship than currently found with the mixed model approach.
All genetic selection in dairy cattle is applied to traits that are measured during the animal’s productive life, mostly those recorded during early productive life because genetic evaluations are best calculated from unbiased early data. Since body lipid is normally accumulated partly as a function of body protein accretion and in part as a function of degree of maturity (which is also related to protein content), it follows that selection for yield in relatively mature life, and concomitant alteration of body lipid profiles, may have altered early life growth profiles as well. If this is the case, parameters of early life growth may be used to predict later life events such as production and functional traits associated with the degree of maturity when these events occur. The objectives of this study were: 1) to model the growth of dairy cows of average and high genetic merit from birth to the end of third lactation and identify any differences in their growth curves.
Cattle breeders, farmers and vets believe that the decline in fertility seen in recent years can be partially attributed to changes in rump angle with selection being for more angular cows. This suggests that animals with pin bones that sit above the hip bones (high rump angle) will have poorer fertility. Few studies have shown a significant relationship between fertility and rump traits. This study investigates the popular belief that high rump angle equates to poor fertility by examining the genetic and phenotypic correlation between rump angle and fertility traits. The relationship between rump angle and fertility was also examined to see if there was an intermediate optimum or threshold of rump angle for good/bad fertility. The correlation of other type traits (udder and composite traits) with fertility was also examined to see if they had potential to add information to the estimation of fertility breeding values.
Health problems in dairy cows are detrimental to animal welfare, cause production losses and lead to treatment costs. Early detection of health disorders can have cow welfare as well as economic benefits. For disorders that affect short-term feeding behaviour, the automatic monitoring of such behaviour by electronic tagging of cows could assist in early detection. The first objective of the study was to describe and quantify changes in short-term feeding behaviour of dairy cows that occur with the onset of the health disorders ketosis, mastitis, acute locomotory problems and chronic lameness. The evaluation of the suitability of an algorithm based on those changes as a diagnostic tool for the early identification of health problems in group-housed dairy cows was our second objective.
We have recently developed a Fertility Index for UK dairy cattle (Wall et al., 2003). After examining national data it was decided that the Fertility Index should be based on sire PTAs for calving interval (CI) and nonreturn rate (NR) after 56 days weighted by their relative economic weights. However, just under half of the available bulls have no milking daughters in the UK. It would take about 4 years from the time of first use in the UK, for a bull to have sufficient daughters for a reliable fertility proof. Waiting this long for fertility information on which to base selection decisions will slow genetic progress and is undesirable as many of these bulls could have fertility proofs in their country of first test. This study examines the feasibility of converting foreign fertility proofs to UK equivalents.
Inbreeding depression leads to the reduction of the mean phenotypic value. There has been a steady increase in inbreeding (F) in the UK since the introduction of reproductive techniques (AI, MOET). There has been an increase in the percent Holstein (%H) in the UK population due to the influx of North American Holstein genes. Crossing these Holsteins to British Friesians can result in the favourable effect of heterosis (het), whereby crossbred progeny out-perform the mid-parent mean for that trait. Of the heterosis in the F1 population, a proportion is lost due to recombination (rec) between parental line genes and is a measure of the epistatic interaction of genes. The purpose of this study was to examine the impact of nonadditive genetic effects (F, het, rec, %H) on the estimation of dairy cow fertility breeding values in the UK.
Recent concern about farm animal welfare has centred on the impact of intensive environments and management practices on the animal. For instance, there has been much concern over the use of close confinement systems (e.g. battery cages or sow stalls) and the perceived negative outcomes of these, including development of abnormal behaviour, stress and resulting physical disease or poor health. However, this emphasis on the physical environment is changing, with greater consideration now being given to animal factors and in particular the selective breeding of farm animals. This is partly because of the growing understanding that genetic selection narrowly focused on production traits may be as significant a factor affecting welfare as the systems in which we manage our farm animals (see Lawrence et al (2004) for a more comprehensive review). However, it is important to note that reduced welfare is not a necessary consequence of selective breeding, and indeed animal breeding may have potential to enhance welfare (e.g. Jones and Hocking, 1999). In this paper we use examples from our own research on dairy cattle, sheep and pigs to illustrate positive and practical contributions that selective breeding can make to reducing welfare problems by creating more balanced breeding programmes or providing tools to address welfare problems.
The use of body tissue by dairy cows to support lactation is increasing, since selection has led to cows that can eat only around half of their incremental feed requirements per unit increase in genetic merit for milk production (Veerkamp et al., 1995). Continuing with this selection policy is likely to result in increasing use of body tissue to fuel milk production and to lead to thinner cows with associated health and fertility problems. This has created increasing interest in body condition scoring (CS) in dairy cows as both an important management tool and also for use in selection indices. The ability to automatically record CS would increase the use of this measure in farm management and enable large volumes of data to be collected for use in national evaluations.
The profit index currently used in the UK was designed in 1992 to combine production and longevity in an optimal manner. There have been no enhancements to this index for some years but during this period the industry has suffered wide-scale disruptions as a consequence of BSE and foot and mouth disease. The quality of data on reasons for culling has reduced, putting greater emphasis on prediction of longevity from type traits, and other issues relating to animal management have risen in priority. Increasing the emphasis on welfare associated traits such as lifespan and health in a widely used selection index will lead to both increased health and welfare of dairy cows and increased public confidence in dairy farming. The objectives of this project were to (1) enhance the prediction of lifespan by incorporating farmer-friendly composite type traits (2) re-evaluate economic weights of traits in £PLI to account for changes in costs/returns and (3) enhance £PLI by the addition of health traits (somatic cell count and lameness).
Visual Image analysis (VIA) of carcass traits provides the opportunity to estimate carcass primal cut yields on large numbers of slaughter animals. This allows carcases to be better differentiated and farmers to be paid based on the primal cut yields. It also creates more accurate genetic selection due to high volumes of data which enables breeders to breed cattle that better meet the abattoir specifications and market requirements. In order to implement genetic evaluations for VIA primal cut yields, genetic parameters must first be estimated and that was the aim of this study. Slaughter records from the UK prime slaughter population for VIA carcass traits was available from two processing plants. After edits, there were 17 765 VIA carcass records for six primal cut traits, carcass weight as well as the EUROP conformation and fat class grades. Heritability estimates after traits were adjusted for age ranged from 0.32 (0.03) for EUROP fat to 0.46 (0.03) for VIA Topside primal cut yield. Adjusting the VIA primal cut yields for carcass weight reduced the heritability estimates, with estimates of primal cut yields ranging from 0.23 (0.03) for Fillet to 0.29 (0.03) for Knuckle. Genetic correlations between VIA primal cut yields adjusted for carcass weight were very strong, ranging from 0.40 (0.06) between Fillet and Striploin to 0.92 (0.02) between Topside and Silverside. EUROP conformation was also positively correlated with the VIA primal cuts with genetic correlation estimates ranging from 0.59 to 0.84, whereas EUROP fat was estimated to have moderate negative correlations with primal cut yields, estimates ranged from −0.11 to −0.46. Based on these genetic parameter estimates, genetic evaluation of VIA primal cut yields can be undertaken to allow the UK beef industry to select carcases that better meet abattoir specification and market requirements.
Parasites of the genera Plasmodium and Haemoproteus (Apicomplexa: Haemosporida) are a diverse group of pathogens that infect birds nearly worldwide. Despite their ubiquity, the ecological and evolutionary factors that shape the diversity and distribution of these protozoan parasites among avian communities and geographic regions are poorly understood. Based on a survey throughout the Neotropics of the haemosporidian parasites infecting manakins (Pipridae), a family of Passerine birds endemic to this region, we asked whether host relatedness, ecological similarity and geographic proximity structure parasite turnover between manakin species and local manakin assemblages. We used molecular methods to screen 1343 individuals of 30 manakin species for the presence of parasites. We found no significant correlations between manakin parasite lineage turnover and both manakin species turnover and geographic distance. Climate differences, species turnover in the larger bird community and parasite lineage turnover in non-manakin hosts did not correlate with manakin parasite lineage turnover. We also found no evidence that manakin parasite lineage turnover among host species correlates with range overlap and genetic divergence among hosts. Our analyses indicate that host switching (turnover among host species) and dispersal (turnover among locations) of haemosporidian parasites in manakins are not constrained at this scale.
This is the official guideline endorsed by the specialty associations involved in the care of head and neck cancer patients in the UK. The disease itself and the treatment can have far reaching effects on speech and swallow function, which are consistently prioritised by survivors as an area of concern. This paper provides recommendations on the assessments and interventions for speech and swallow rehabilitation in this patient group.
• All multidisciplinary teams should have rehabilitation patient pathways covering all stages of the patient's journey including multidisciplinary and pre-treatment clinics. (G)
• Clinicians treating head and neck cancer patients should consult the National Cancer Rehabilitation Pathway for head and neck cancers. (G)
• All head and neck cancer patients should have a pre-treatment assessment of speech and swallowing. (G)
• A programme of prophylactic exercises and the teaching of swallowing manoeuvres can reduce impairments, maintain function and enable a speedier recovery. (R)
• Continued speech and language therapist input is important in maintaining voice and safe and effective swallow function following head and neck cancer treatment. (R)
• Disease recurrence must be ruled out in the management of stricture and/or stenosis. (R)
• Continuous radial expansion balloons offer a safe, effective dilation method with advantages over gum elastic bougies. (R)
• Site, length and completeness of strictures as well as whether they are in the presence of the larynx or not, need to be assessed when establishing the likelihood of surgically improved outcome. (G)
• Primary surgical voice restoration should be offered to all patients undergoing laryngectomy. (R)
• Attention to surgical detail and long-term speech and language therapist input is required to optimise speech and swallowing after laryngectomy. (G)
• Patients should commence wearing heat and moisture exchange devices as soon as possible after laryngectomy. (R)
Since cow-calf operations are large contributors of agricultural greenhouse gas (GHG) emissions in North America, consequences of pasture species composition, weaning age, and stocking rate decisions were examined by operation size, calving season, and pasture fertility. Fixed resource use and seasonal prices affected the mix of forage and beef production. Overall, adding fertilizer to pasture was unprofitable, resulting in increased stocking rates and greater emissions. Calving season and attendant breeding failure rates influenced the relative profitability of the analyzed beef-production strategies, which in turn affected farm GHG emissions. More-efficient practices led to greater amounts of beef sold per bred cow.
The history of the feed industry is pertinent in terms of understanding how and why certain practices have evolved. Some of these practices have been superseded by modern, more natural alternatives, for example the traditional use of antibiotics in feed. In other cases, such as inorganic minerals, more natural versions akin to those found in plant and animal materials are available, although these new initiatives are still being taken up globally. Research continues to increase our knowledge and understanding of nutrient balance and digestion, and in some species this is more advanced than others. The following paper represents the first complete history of the feed industry, its major milestones, and projects how it might continue to utilise new technology developments to improve animal feeding practices.
Transmission electron microscopy (TEM) based orientation mapping has been used to measure the length fraction of coherent and incoherent Σ3 grain boundaries in a series of six nanocrystalline Cu thin films with thicknesses in the range of 26–111 nm and grain sizes from 51 to 315 nm. The films were annealed at the same temperature (600 °C) for the same length of time (30 min), have random texture, and vary only in grain size and film thickness. A strong grain size dependence of Σ3 (coherent and incoherent) and coherent Σ3 boundary fraction was observed. The experimental results are quantitatively compared with three physical models for the formation of annealing twins developed for microscale materials. The experimental results for the nanoscale Cu films are found to be in good agreement with the two microscale models that explain twin formation as a growth accident process.
Genetic improvement is easy when selecting for one heritable and well-recorded trait at a time. Many industrialised national dairy herds have overall breeding indices that incorporate a range of traits balanced by their known or estimated economic value. Future breeding goals will contain more non-production traits and, in the context of this paper, traits associated with human health and cow robustness. The definition of Robustness and the traits used to predict it are currently fluid; however, the use of mid-infrared reflectance spectroscopic analysis of milk will help to create new phenotypes on a large scale that can be used to improve the human health characteristics of milk and the robustness of cows producing it. This paper describes the state-of-the-art in breeding strategies that include animal robustness (mainly energy status) and milk quality (as described by milk fatty acid profile), with particular emphasis on the research results generated by the FP7-funded RobustMilk project
This study was designed to evaluate the effects of algal and yeast β-glucans on the porcine gastrointestinal microbiota, specifically the community of Lactobacillus, Bifidobacterium and coliforms. A total of 48 pigs were fed four diets over a 28-day period to determine the effect that each had on these communities. The control diet consisted of wheat and soya bean meal. The remaining three diets contained wheat and soya bean meal supplemented with β-glucan at 250 g/tonne from Laminaria digitata, Laminaria hyperborea or Saccharomyces cerevisiae. Faecal samples were collected from animals before feeding each diet and after the feeding period. The animals were slaughtered the following day and samples were collected from the stomach, ileum, caecum, proximal colon and distal colon. Alterations in Lactobacillus in the gastrointestinal tract (GIT) were analysed using denaturing gradient gel electrophoresis (DGGE) profiles generated by group-specific 16S rRNA gene PCR amplicons. Plate count analysis was also performed to quantify total coliforms. DGGE profiles indicated that all β-glucan diets provoked the emergence of a richer community of Lactobacillus. The richest community of lactobacilli emerged after feeding L. digitata (LD β-glucan). Plate count analysis revealed that the L. hyperborea (LH β-glucan) diet had a statistically significant effect on the coliform counts in the proximal colon in comparison with the control diet. β-glucan from L. digitata and S. cerevisiae also generally reduced coliforms but to a lesser extent. Nevertheless, the β-glucan diets did not significantly reduce levels of Lactobacillus or Bifidobacterium. DGGE analysis of GIT samples indicated that the three β-glucan diets generally promoted the establishment of a more varied range of Lactobacillus species in the caecum, proximal and distal colon. The LH β-glucan had the most profound reducing effect on coliform counts when compared with the control diet and diets supplemented with L. digitata and S. cerevisiae β-glucans.