The peri-parturient period is unsettling for dairy cows as they move from the dry period, through parturition, cow-calf separation and into the milking herd. The changes in physiological state, environment and social grouping through this period are likely to be particularly manifest in primiparous cows. Lactating dairy cows may be expected to spend up to 13.8 hours/day lying (Tucker and Weary, 2007), this has been shown to alter through the peri-parturient period (Huzzey et al (2005). The mean lying time for healthy cows at this farm was 11 hours day (Blackie et al, 2008).

The aim of the present study was to assess the changes in activity levels of first parity cows before and after calving as compared to their multiparous herd mates.

Associations between animal behaviour and emissions of methane (CH4) and ammonia (NH3) have been noted in studies of grazing cattle (Lockyer, 1997) and feedlot confined cattle (Harper et al., 1999, Flesch et al., 2007). Methane emissions have been predicted as being greatest during bouts of rumination (Harper et al., 1999) whereas the emissions of the indirect greenhouse gas ammonia tends to be low early in the morning but increasing rapidly in the early afternoon after which a rapid decline until sunset (Flesch et al., 2007). With the exception of Harper et al., (1999) there are few complete data sets that examine the interaction between animal behaviour and greenhouse gas emissions from intensive animal production systems. The current study aimed to investigate the relationship between animal behaviour and emissions of CH4 and NH3 in a beef feedlot system in northern Australia.

Protein is an expensive nutrient in pig diets and high protein diets lead to high N excretion, a source of pollution. Low protein nutritional strategies are therefore needed, but these often increase fat deposition. This study compared three nutritional strategies differing in protein and energy supply using genotypes with different propensities for fat deposition.

Growth rate is an important performance indicator in pig production and therefore influences profitability. There is also evidence that faster growing pigs have superior tenderness (MLC, 1989), possibly linked to faster muscle protein deposition through the activity and expression of proteolytic enzymes. Slow growth could also result in higher boar taint levels in entire male pigs because they will be older and sexually more mature at slaughter (MLC, 1989). The current project was therefore undertaken to investigate the effect of variations in growth rate on tenderness and boar taint.

The production of fuel from renewable energy sources has generated increasing interest in recent years and biofuel production is being encouraged within the United Kingdom. If current government targets are to be met, approximately 2.7 million tonnes of oil seed rape are needed to supply biodiesel which will result in a significant amount of the by-product glycerol. Glycerol may be a useful source of energy in diets for pigs but there is limited research on the optimum level of inclusion, digestible energy (DE) content or on the effect on performance. Research by Mourot et al (1994) suggested that glycerol tended to reduce performance but significantly improved meat quality as assessed by drip loss. The aim of this study was to investigate the effect of glycerol inclusion in finishing pig diets on performance and meat quality.

A high degree of variable growth rate between pigs of the same age has been associated with overall poor herd performance and decreased profitability (Magowan et al., 2007). The aim of the current study was to reduce the variation in growth rate between pigs by grouping them in either uniform or mixed weight groups at weaning and offering them either ‘special’ or ‘normal’ dietary regimes during the post weaning and finishing periods.

The value of a pig carcass is largely based on its lean meat percentage (LM%). The ultimate method of accurately measuring the lean meat percentage is a full dissection of the carcass. However, this is both time consuming and expensive. Lean meat percentage prediction equations have been established for various ‘probes’ and indicator cuts. Although these prediction equations have low (less than 2.5) Root Mean Square Errors of Prediction (RMSEP) and high R_a2 values, research continues to investigate other methods to produce equations with greater accuracy and to identify alternative techniques to full dissection. The aim of this experiment was to investigate the accuracy of lean meat percentage prediction equations using data gathered from 1) grading probes, 2) primal cuts and 3) photographs from cross sections of the loin.

Consumption of pork is declining in the UK, while demands of costumers for improved pork quality are rising. Various experimental studies suggest that dietary supplements such as vitamins and minerals could help to improve pork quality without negatively affecting other aspects of the production cycle (e.g. growth, welfare). However, results from different experiments are inconsistent, suggesting different magnitudes of effects caused by the same dietary supplementation. Meta-analysis (MA) is a statistical tool designed to combine results from different studies in a statistically sound manner to produce robust quantitative estimates of the impact of specific factors on traits of interest. In this study we tested the feasibility of meta-analysis for determining how supplementation of vitamin E as antioxidant reduces lipid oxidation and improves redness of pork over time, extending thus its shelf-life.

In order to assess the nutritive value of pig diets, performance and digestibility trials must be conducted as there is no accurate alternative to predict nutritive value. However, the use of near infrared reflectance spectroscopy (NIRS) to predict performance from feed ingredients has been shown to have potential. Owens et al (2007) investigated the use of NIRS to predict the performance of broilers offered wheat-based diets, through scanning of whole wheat, and observed that NIRS accurately predicted liveweight gain and gain:feed. The aim of this study was to investigate if NIRS could be used to predict the performance of pigs, through scanning of the complete diet.

Compensatory growth studies in pigs have indicated that their meat tends to have increased proteolysis and a faster rate of tenderisation (Kristensen et al., 2002). The postmortem rate of muscle glycogen decline influences meat quality, for example in PSE. There are two forms of muscle glycogen, acid soluble macroglycogen (MG) and acid insoluble proglycogen (PG), which have different turnover rates in vivo (Graham et al, 2001). The aim of this study was to determine whether a compensatory growth feeding regime would influence meat quality characteristics and whether the changes in feed availability during the trial would differentially alter the postmortem degradation of the different forms of glycogen.

Efficiency of feed is of primary commercial importance in pig production. Interest in nutritional solutions to increase feed efficiency has increased since the bans/restrictions on the use of antibiotic feed additives and heavy metals. DeviGuard® is a mixture of short, medium and long chain fatty acids all of which are encapsulated to reach the hind gut. Fatty acids have been shown to be the preferred energy source of the entrocytes in the gut, active against pathogenic bacteria and anti-inflammatory. The aim of the present study was to assess the effects of fatty acid supplementation on the performance and digestibility of growing pigs.

Young pigs kept intensively, are very sensitive to the source of dietary protein (Maxwell et al., 2003). Many dietary proteins produce allergic reactions in which diarrhoea, reduced growth, and increased mortality can occur (Bimbo and Crowther, 1992). Various protein sources have been tested in early-weaned pig diets in an attempt to overcome these problems and to decrease diet cost. Fish meal analog (FMA), (a product of Mid-South Milling Co., Memphis, TN) based on animal proteins has been reported to have a composition very similar to fish meal, thereby possessing excellent protein and AA source for young pigs (Maxwell et al., 2003). It is less expensive and more readily available. This may therefore provide a high quality protein and AA source for use in starter pig diets at costs lower than those associated with fish meal. This study was therefore conducted to determine the potential of FMA as a replacement for 72% crude protein-imported fish meal (IFM) in diets of starter pigs.

The fatty acid profile of pork can be easily manipulated via the diet of the pig. The most common aim is to increase the proportion of unsaturated fatty acids, in particular omega 3 fatty acids. Kim et al. (2008) reported that the breed of pig can have an effect on the fatty acid composition of pork. The aim of the current experiment was to investigate the effect of terminal sires of different breed commonly used in Northern Ireland on the fatty acid profile of pork.

Meat tenderness is the single most important quality attribute in consumer acceptance studies of meat eating quality. Several mechanical-based techniques have been developed to provide an objective measure of meat tenderness that have good correlation with sensory tenderness, as assessed by trained taste panel. The classic Warner-Bratzler shear force technique (WBSF) has shown correlations with sensory tenderness in the range of -0.39 to -0.77 (Van Oeckel et al., 1999; Shackelford et al., 1999a), whilst the Volodkevitch bite test attempts to imitate the incisor biting action by a compression method. A rapid slice shear force (SSF) test, which uses only one steak and hot meat (significant benefits in a commercial environment), had a stronger correlation with taste panel tenderness scores than WBSF (Shackelford et al., 1999b). The Meat Industry Research Institute of New Zealand (MIRINZ) test results, transformed into categories, was highly correlated (-0.97) with sensory tenderness (Bickerstaffe et al., 2001). The objective of this study was to evaluate the associations between objective physical measures (SSF, MIRINZ and Volodkevitch) and taste panel tenderness scores in beef.

Prediction of eating quality of beef at an early stage post mortem would enable selection of carcases for specific markets. Shackelford et al (2004) reported the design of NIR equipment suitable for measurement of larger areas of the muscle and also the prediction of 14 day slice shear force values from NIRRS measurements made at 2 days post slaughter (Shackelford 2005). The aim of the present study was to evaluate the use of equipment of a similar design and manufacture to that used by Shackelford et al (2005), to predict Warner-Bratzler Shear force values in carcases with a smaller range of marbling than found in the USA.

Prediction of eating quality of beef at an early stage post mortem would enable selection of carcases for specific markets. Shackelford (2004) reported the design of near infra red (NIR) equipment suitable for measurement of larger areas of the muscle and also the prediction of 14 day slice shear force values from NIR measurements made at 2 days post slaughter (Shackelford 2005). The aim of the present study was to evaluate the use of equipment of a similar design and manufacture to that used by Shackelford et al (2005), to evaluate repeatability and time of measurement of NIR spectra on the prediction of Warner-Bratzler Shear force values.

The amount and fatty acid (FA) composition of beef intramuscular fat (IMF) are key factors that influence technological and sensory quality, especially shelf-life (lipid and pigment oxidation) and flavour. Furthermore, consumers are interested in the fat composition of meat, as nutritional guidelines are recommending a lower saturated FA (SFA) intake due to its association with cardiovascular diseases. The amount and composition of ruminant IMF, which depends on factors such as the genetic origin of the animals, feeding regime, age or live weight, influences the final quality of the product, which also explains the increasing interest in defining the FA profile of meat. However, quantitative chemical techniques for the determination of FA involve extraction of total lipids and determination of FA methyl esters by gas chromatography, so that this procedure is costly, time-consuming and generates hazardous waste. The use of near infrared reflectance spectroscopy (NIR) is increasing in food analysis because it offers several advantages over conventional methods, giving fast, non-destructive, clean and cost effective measurements. Therefore, the aim of this study was to test the on-line estimation of the concentration of major individual FA (C16:0, C18:0 and C18:1) and main groups of FA (SFA, monounsaturated FA (MUFA) and polyunsaturated FA (PUFA)) of beef IMF using NIR, by direct application of a fibre-optic probe to the M. longissimus thoracis with no prior sample treatment.

X-ray computed tomography (CT) scanning makes use of the different rates at which the tissues attenuate X-rays depending on their densities. CT muscle density (MD) is the average pixel value for this tissue in the CT images and is related to real density of the tissue, which depends on its chemical composition. One of the components determining muscle density is intramuscular fat (IMF). Studies in sheep have shown that MD, measured in vivo, was phenotypically and genetically correlated to IMF and to fatty acid (FA) composition in Scottish Blackface lambs (Karamichou et al. 2006). Intramuscular fat and FA are important traits to measure due to their association with the nutritional value and eating quality of meat. A novel automatic image analysis for spiral CT scans (SCTS) of beef primal cuts allows very accurate estimations of primal cut and carcass composition with R2 of 0.90 to 0.99 (Navajas et al., 2008). The aim of this study was to investigate the associations of MD of beef primal cuts with IMF and FA profile in Aberdeen Angus (AA) and Limousin (LIM) cattle, based on the CT thresholds estimated as part of the development of the image analysis described by Navajas et al. (2008).

X-ray computed tomography (CT) scanning of live animals and carcasses provides a very accurate assessment of the weights of fat, muscle and bone in pigs (Dobrowolski et al., 2003) and sheep (Johansen et al., 2007). Although the limiting size of the CT gantry prevents CT scanning of live beef cattle, beef primal joints are small enough to be scanned. Navajas et al. (2008) explored the use of spiral CT scanning (SCTS) to quantify beef carcass composition. The automatic image analysis developed provided very accurate assessments of primal and carcass composition (Navajas et al, 2008). The objective of this study was to evaluate the accuracy of this novel method for assessing beef primal cut and carcass composition in an independent dataset.

Quantification of the diet consumed in free-ranging ruminants is essential to manipulate both agricultural performance and environmental impact. A common non-invasive approach for determining diet composition is based on using long-chain, saturated hydrocarbons (n-alkanes) as markers (Dove and Mayes, 1996). However a major drawback of using this approach is the time and related expense associated with extracting these compounds. Spectroscopic imaging is a rapidly evolving research area, with the potential to provide real-time solutions. Previous applications have shown its ability to detect chlorophyll and its breakdown products in faeces as markers of contamination in carcasses to reduce pathogen load entering the food chain (Ashby et al. 2003). Chlorophyll is ubiquitous in green plants and thus livestock diets. During digestion in the gut, chlorophyll is only partially degraded to coloured and fluorescent intermediates: phaeophytin, chlorophyllide, phaeophorbide and pyrophaeophorbide derivatives of chlorophylls a and b. It is these compounds that are detected by spectral imaging of the faeces, and comparisons of spectral wavelength profiles may provide comparative information about the animals’ diet.