bluuebunny/crossref_metadata_2025_split huggingface dataset:
The Role of Biology in the Fossilization of Embryos and Other Soft-Bodied Organisms: Microbial Biofilms and Lagerstätten
Authors: Raff Rudolf A. , Raff Elizabeth C. 
Published: June 2019

Soft-tissue fossils are among the most striking and informative remains of extinct organisms. Although relatively rare, they are diverse, ranging from single microbial cells to nuclei and chromosomes; algae; metazoan embryos and larvae; flowers; complete, small, soft-bodied metazoans, metazoan tissues; integumentary structures such as melanosomes; skin texture, vertebrate feathers and hair, insect wings with color patterns, and sometimes even the entire bodies of large animals. The susceptibility of newly dead soft tissues to physical destruction, consumption, and microbial decay makes their preservation unlikely under most taphonomic conditions. In addition, their vulnerability to rapid autolysis, bioturbation, and destructive physical processes requires that rapid biological events must occur as the critical first steps of fossilization. An understanding of the processes by which biological remains enter the fossil record is important in inferring what non-microbial and microbial processes were operative in Lagerstätten. Paleontologists have recognized that microbial biofilms often accompany soft-tissue fossils, and have suggested that bacteria play an active role in soft tissue fossilization, but that role must be determined experimentally with living bacteria and dead tissue.Marine embryos and marine bacteria are used to investigate the processes that mediate early steps in soft-tissue preservation because they offer simple systems for laboratory investigation of the roles of autolysis-blocking environments, microbial interactions, biofilm formation, and authigenic mineralization in taphonomy. Understanding microbially mediated preservation of embryos may supply new insights into a more general biology of fossilization.
Explanation in Psychology: Truth and Teleology
Authors: Papineau David 
Published: June 2019

A number of recent writers have argued that we should explain mental representation teleologically, in terms of the biological purposes of beliefs and other mental states.A rather older idea is that the truth condition of a belief is that condition which guarantees that actions based on that belief will succeed.What I want to show in this paper is that these two ideas complement each other. The teleological theory is inadequate unless it incorporates the thesis that truth is the guarantee of successful action. Conversely, the success-guaranteeing account of truth conditions is incomplete until it is placed in a teleological context.
Genetic changes in layer breeding: Historical trends and future prospects
Authors: Preisinger Rudolf , Flock Dietmar K. 
Published: June 2019

SummaryIn commercial egg type chicken breeding three and four way crosses are used to produce commercial layers. The primary breeders are using closed nucleus breeding programmes, with birds kept under maximum biosecurity. All grand parents and parents are produced from a closed nucleus for the world wide demand of commercial layers. The breeding goals have been focused for several decades on increasing number of eggs per hen housed. Additional traits have become more important during the last decade, i.e. feed efficiency, internal and external egg quality and general adaptability. Prior to each selection, weights for individual traits within the selection index are adjusted to meet market demands. Breeding stock and commercial layers have to be bred to perform adequately in a variety of systems ranging from large intensive cage units to free range management under different environmental conditions world-wide.Despite intensive selection for egg production the decrease in genetic variation observed in closed commercial lines is not yet critical. Peak production is approaching the biological limit of one egg a day. During this period genetic and phenotypic variation have been significantly reduced. But for early production (sexual maturity) and late production (persistency) genetic variation is still high. In a mating scheme avoiding full and half sib matings no serious inbreeding depression is observed. To achieve continued future genetic progress, selection pressure will shift to other traits like internal and external egg quality and perhaps behaviour traits which still respond to selection.Primary breeders are responding to this challenge by testing pedigreed cross-line hens in a wide range of environments and housing systems while the pure-line elite stock is kept under conditions of maximum biosecurity. Marker assisted selection is already part of commercial breeding programmes. In the past, blood typing has been used to improve Marek's resistance, whereas today anonymous microsatellites which are linked to traits of economic interest are used for selection. In particular, selection between full sib males can give a major improvement.The whole industry is getting more specialised. While the genetic potential of the birds is improved management and nutrition have also to be adapted to changing demands. The general goal for the future is to breed chickens with the ability to function well within a wider range of production conditions and do not respond to the slightest stress.
Issues arising from genetic selection for growth and body composition characteristics in poultry and pigs
Authors: Emmans G. C. , Kyriazakis I. 
Published: June 2019

AbstractBreeders of poultry and pigs have selected for some combination of increased growth rate, decreased fatness and increased muscularity. Increasingly various fitness traits are included in the index used. The consequences of such selection include complex effects on nutritional and environmental requirements, at least some of which are reliably predictable using suitable models. Appropriate changes to the environment and to nutrition as selection proceeds will help to avoid unwanted effects occurring. Among the predictable effects are that higher ratios of nutrients to energy, and lower temperatures, will be needed by the improved genotypes. Selection for growth rate must eventually exhaust the capacity of the support systems – digestive, respiratory, circulatory and excretory – to cope with the increased metabolic rate. Selection for increased yield of valuable parts will cause these problems to occur earlier. While it is possible to predict that these problems will occur it cannot be predicted when they will. Breeders need to be aware of these problems, and use all possible routes to help them in reducing their severity. Where the appropriate actions for fitness selection, and nutritional and environmental modifications, are taken the occurrence of the problems will be delayed.
An investigation of the thermal death kinetics ofMycobacterium paratuberculosisduring pasteurisation
Authors: Rowe M.T. , Grant I.R. , Ball H.J. , Pope C. 
Published: June 2019

AbstractMycobacterium paratuberculosis is the known cause of Johne's disease in cattle and has been implicated as a cause of Crohn's disease in humans. Concern has been expressed that the organism, which is excreted in milk and faeces of infected cattle, may be transmitted via pasteurised milk. This is largely from work that has shown an unacceptable risk of survival of the organism when it is present in raw milk at numbers exceeding 102cfu/ml. Three possible reasons for this apparent heat resistance were investigated viz. use of a milk heating menstruum, presence of a heat resistant sub–population, and the tendency of the organism to form clumps. Heat resistance studies using a combined acid–fast/viability stain, and a comparison of the relative heat sensitivities of clumped and de-clumped M. paratuberculosis cells provided circumstantial evidence that it is the organism's tendency to form clumps which confers the apparent heat resistance. This work casts doubt on the efficacy of current commercial pasteurisation heat treatments (72°C/15s) for the inactivation of M. paratuberculosis. This would be of concern if a link between M. paratuberculosis and Crohn's disease is eventually established.
Impact of genetic polymorphism on milk powder manufacture and processing
Authors: Hill J. , Boland M. , Harris P. , Paterson G. 
Published: June 2019

AbstractRecombined milks manufactured from milk powders made from milk produced by b-lactoglobulin (b-LG) AA phenotype cows were not suitable for processing into ultra-heat-treated (UHT) milk products as these milks rapidly fouled heat exchanger surfaces when compared with standard mixed b-LG variant milk. Recombined milks manufactured from powders from b-LG BB phenotype milk generally gave low fouling rates upon UHT treatment and in some cases gave almost negligible fouling of UHT heat exchanger surfaces. Fresh milk from b-LG AA phenotype cows fouled evaporator preheaters more rapidly than standard milk, whereas fresh milk produced from b-LG BB phenotype cows fouled evaporator preheaters less rapidly than standard milk. Recombined milks manufactured from powders made with milk from k-casein (k-CN) BB phenotype cows fouled heat exchanger surfaces more rapidly than recombined milks manufactured from powders from milk from k-CN AA phenotype cows.
Influence of dietary copper sulphate supplementation on the milk fatty acid composition of dairy cows
Authors: McNamee B.F. , Fearon A.M. , Pearce J. 
Published: June 2019

AbstractThe experiment was designed to investigate the effect of increasing the concentration of Cu2+ in the diet of the lactating dairy cow with a view to stimulating the activity of the mammary gland △9–desaturase enzyme system to increase the C18:1/18:0 ratio in the milk fat.In a preliminary study, two lactating dairy cows were provided with ground rapeseed/maizebased concentrates containing either a normal or a high concentration of supplementary Cu2+, the animal offered the normal concentration supplement was also provided with an oral CuSO4 solution drench so that both animals received an equal daily supply of Cu2+. Daily blood samples were collected from the cows and total plasma Cu2+ concentration was determined. A blood plasma lipid analysis was also carried out. In a second study, eight lactating dairy cows were provided with a silage and concentrate diet. The lipid portion of the concentrates was provided by either ground or unground rapeseed while the Cu2+ in the mineral supplement of the unground rapeseed-based concentrate was manipulated to provide one of the following three concentrations of Cu2+ in the concentrate (mg/kg DM); <10, 50 or 100. The subsequent milk fat was analysed for fatty acid composition.Presentation of an increased concentration of Cu2+ to the cow was more efficiently absorbed when provided in the concentrate mix than when provided as a CuSO4 solution in an oral drench. Increased dietary Cu2+ in the concentrates was successful at increasing the concentration of plasma Cu2+ from a normal concentration of 80–100 mg/cm3 to over 200 mg/cm3. An increased concentration of Cu2+ in the blood of the cows in the first experiment resulted in a significant increase (P<0·05) in the C18:1 content of the plasma lipid, possibly through the increased activity of the intestinal △9–desaturase enzyme system.The composition of the milk, including the fatty acid composition of the milk fat, from the second experiment was unaffected by the concentration of Cu2+ in the diet of the dairy cows within the concentration range of <10 to 35 mg/kg DM per day.
Life-time organisation and management of reproduction in the dairy cow
Authors: Wathes D. C. , Beever D.E. , Cheng Z. , Pushpakumara P.G.A. , Taylor V.J. 
Published: June 2019

AbstractAchieving adequate fertility is essential in any dairy unit, but is compromised by genetic selection for increased yield. Selection has altered the somatotrophic axis and resulted in cows which mobilise more body tissue for milk production in early lactation, thus prolonging both the depth and duration of the post partum negative energy balance. Poor energy status is reflected in altered metabolic parameters including raised urea and decreased insulin-like growth factor-I (IGF-I) and insulin concentrations, which adversely affect ovarian cyclicity and early embryo survival. Attempts to optimise the diet in terms of energy and protein content have generally been aimed at increasing milk production further rather than improving fertility. Advances in biosensor technology now provide us with the opportunity to monitor production, fertility and health parameters of each cow. Integration of this information should improve the timing for inseminations and could assist in selecting diets more suited to the needs of the individual cow. Genetic selection may in future be used to produce cows optimised for a particular type of management system. In both cases we need a greater understanding of the rules governing nutrient partitioning at different stages of the cows' life cycle to ensure that diets selected are cost effective and achieve an appropriate balance in promoting production, reproduction and health.
Nutritional and grazing management of the dairy cow
Authors: Dewhurst R. J. , Rutter S. M. , Rook A. J. 
Published: June 2019

AbstractThe pre-requisites for nutritional management of dairy cows are information about how much feed is being consumed as well as the nutrients that are being derived from that feed. Studies of feed intake and nutrient supply have been limited by difficult experimental techniques, particularly with grazing animals. The models derived from much earlier work are of only general applicability and there is a need for more site-specific information in order to benefit further from conceptual advances.We have adopted a different approach to studying herbage intake and nutrient supply, using less-invasive approaches as well as techniques that monitor more accessible aspects of these processes, such as jaw movements. These techniques have a major advantage, in addition to their value as research tools, because they could translate directly into commercial applications in on-farm monitoring. The use of diagnostics and behavioural recording is well explored in relation to health monitoring; here we argue for its potential to advance the application of knowledge about grazing and nutrition. We will illustrate this approach using our experiences in measuring grazing behaviour, using IGER behaviour recorders and assessing rumen function, using a series of non-invasive techniques.The IGER grazing behaviour recorder allows us to record jaw movements and hence grazing and ruminating time and bite dynamics. It also allows the recording of steps and is now being developed to incorporate non-invasive rumen state sensors. It has made a major contribution to our understanding of the foraging strategies of grazing animals and their effect on herbage intake. This technology has the potential to be developed for on-farm monitoring of foraging behaviour providing valuable inputs to the prediction of herbage intake, in decision support systems for grazing.The introduction of concept of protein degradation and microbial synthesis in the rumen are significant advances in protein rationing schemes. However, real progress has been limited because the lack of consistent experimental results means that models have little relevance to specific farm situations. We foresee considerable opportunities to monitor products of rumen degradation and synthesis that appear in milk (e.g. odd-chain fatty acids) or breath (e.g. sulphides).Taken together these technologies open the possibilities of an entirely new approach to nutritional management of dairy cows, with site-specific recommendations based on information gathered using new sensors that are incorporated into computerised feeding equipment and milking parlours.
A vision of poultry production in the UK
Authors: Perry G. C. 
Published: June 2019

AbstractCurrent commercial poultry production in the UK faces many challenges which make it difficult to confidently predict the future. Changing legislation, responding largely to welfare pressures, is one such challenge. Additionally, consumer demands are widening. Eggs and meat from stock which is organically produced, or fed on rations containing no genetically modified ingredients, or free range produced, or corn fed are some of the assurances sought by the purchaser and consumer. Although the market place already offers such produce it is difficult to predict the extent to which they will penetrate a market which developed largely through the use of intensive production systems. The alternatives to intensively produced eggs and meat are more expensive to produce and therefore purchase and consequently are susceptible to changes in standards of living and the affluence of the consumer.This paper briefly describes current commercial practices and some of the specific challenges arising from new legislation.A description of some specific requirements of birds highlights areas where improvements, in terms of performance, production efficiency, and welfare might be gained. Since the overwhelming majority of eggs and meat is produced in intensive, highly automated systems, there is an obvious need for an integrated approach featuring engineers and the poultry industry to refine and further develop technology which better serves the birds, and ultimately, the consumer.It is concluded that the UK cannot compete in production costs with some other areas of the world and as retailers increasingly source their goods worldwide, the UK poultry producer may have to resort to the production of products which satisfy niche demands.
Effects of body condition at calving, post-partum nutrition and calf access on the interval from calving to first ovulation in beef cows: Cow performance and metabolism
Authors: Sinclair K. D. , Molle G. , Revilla R. , Roche J. F. , Quintans G. , San Juan L. , Sanz A. , Mackey D. R. , Diskin M. G. 
Published: June 2019

The prolonged interval from calving to first ovulation in beef cows is primarily due to the suckling-mediated inhibition of pulsatile LH release. Undernutrition both before and after calving also suppresses LH release, reduces ovarian follicular growth and delays ovulation. The interactive effects of these factors on the interval from calving to first ovulation in beef cows were quantified by studying the incidence of ovulation, following acute calf isolation and once-a-day suckling (restricted access), after emergence of the fourth follicular wave post partum in cows in differing body condition at calving and offered low or high planes of nutrition after calving.The experiment was a 2 x 2 x 2 factorial design, in which the factors were body condition score at calving (Low v. Moderate), feeding level after calving (0.6 v. 1.0 MJ ME/d/kg M0.75), and restricted (once-a-day) v. ad libitum access and suckling. The experiment, duplicated at each of the four participating sites, involved 16 Simmental, 16 Sarda, 16 Brown Swiss and 16 Hereford x Friesian multi-parous cows. Follicle growth was monitored daily from day 21 post partum until the earlier of second ovulation or Day 90 post partum using transrectal ovarian ultrasonography.
Body weight and P2 measurements as estimates of body tissue losses of lactating primiparous and multiparous sows
Authors: Probert L.D. , Wiseman J. , Jagger S. 
Published: June 2019

Reproductive failure, especially in young sows, is the major contributor to the steady rise in sow culling and mortality rates in recent years. There is now considerable interest in the nutrition of the gilt and its effect on production characteristics and subsequent reproductive performance. Both fat, and more recently lean tissue, have been postulated to play singularly important roles. The objective of the current study was to use production performance criteria of both primiparous and multiparous animals to estimate the proportions of fat and lean tissue mobilised during lactation.Ninety two animals, forty five gilts and forty seven third parity sows, based at the University commercial pig unit, were used in this study. All animals were weighed and monitored for P2 backfat depth on entry to the farrowing house, during lactation and, finally, at weaning. The data for each individual animal was then used to calculate, by linear regression, the daily rate of loss of both body weight and P2 backfat depth during lactation. These responses were then utilized to calculate the weight and P2 backfat level of each animal on days 1 and 28 of lactation.
The response of net milk protein output to metabolisable protein supply in dairy cows
Authors: Mansbridge R.J. , Metcalf J.A. , Oldham J.D. , Blake J.S , Newbold J.R. 
Published: June 2019

The UK Metabolisable Protein (MP) system (AFRC, 1993) assumes that MP intake is converted to milk net protein with an efficiency of 0.68 and that MP for maintenance is 2.30*liveweight0.75. Previous work has indicated that the efficiency of MP use for milk production may be too high or that the amount of MP required for maintenance may be too low (Newbold et al, 1994). This experiment was designed to investigate the relationship between MP supply and net protein output in diets of differing MP to Metabolisable Energy (ME) ratios.Four‘cornerstone’ diets based on grass and maize silage (0.33:0.67 dry matter basis), were formulated to meet ME requirements and either 0.25 above or below MP requirements for either 46 or 24 kg milk/d. A total of 72 multiparous Holstein cows, on average 46 days post calving at the start of the study, were grouped into blocks of 4 cows on the basis of milk energy output in the covariance period. ME and MP requirements for each block of cows were calculated from milk energy and milk protein yield in the covariance period.
Impaired deposition of vitamin E in lambs of two breeds fed a dry pelleted complete diet and its effects on meat quality
Authors: Enser M. , Demirel G. , Wood J.D. , Nute G.R. , Wachira A.M. , Sinclair L.A. , Wilkinson R.G. 
Published: June 2019

Vitamin E is an important nutrient for lambs and low levels in tissues as a result of either low intake, poor absorption or excessive utilisation results in myopathy (pale muscle). The causes of deficiency are incompletely understood, especially as it can occur when lambs are consuming good quality grass containing high levels of vitamin E. We now report an occurrence of low tissue levels of vitamin E in lambs of two breeds raised on complete dry pelleted rations and its effect on meat quality and fatty acid composition.96 male lambs, half Suffolk x Lleyn and half Scottish Blackface, with average live weights of 24 kg and 18kg respectively were individually penned and randomly allocated to one of 6 isoenergetic isonitrogenous diets based on dried grass, molassed sugar beet pulp, soya bean meal and molasses and containing two levels of vitamin E, 100 (low) and 500 (high) g/kg DM.
The effects of the ratio of silage to concentrates in the diet on the performance and carcass composition of continental bulls
Authors: Patterson D.C. , Steen R.W.J. , Moore C.A. 
Published: June 2019

Continental bulls of high genetic potential for lean tissue growth (½ Blonde d’Aquitaine ⅜ Charolais genotype) have exhibited high rates of liveweight and carcass gain when grass silage based diets were offered with a moderate proportion of concentrates, i.e. concentrates comprising 0.40 of total dry matter intake (Patterson et al., 1994). It was the objective of the present experiment to examine the effect of forage to concentrate ratio in the diet on growth rate and carcass composition.The experiment was a five treatment continuous design randomised block arrangement with five concentrate ratios in the total diet (DM basis) namely: 0.25, 0.40, 0.55, 0.68 and 0.75 and grass silage (D value 730 g/kg) as the sole forage. The diets were fed ad libitum. A total of 45 continental bulls (½ Blonde d’Aquitaine ⅜ Charolais) were used with mean initial and final live weights of 467 and 651 kg respectively.