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Context Reducing methane emissions from livestock systems is a global priority. Genetic selection could play a vital role, but direct measurement of methane emissions from individual sheep is expensive and difficult. Previous research studies, in the UK and internationally, have identified links between rumen morphology, measured by computed tomography (CT) scanning, and methane emissions from sheep. In particular, larger reticulo-rumen volumes (RRvol) are associated with increased methane emissions. Aims The aims were to investigate RRvol differences between breeds and sires, in Texel and Scottish Blackface lambs, and to estimate genetic parameters of RRvol and other production traits in Texel sheep. Methods Scottish Blackface (SBF; n = 151) and Texel (TEX; n = 111) lambs of both sexes, reared together on low-ground pastures, were CT scanned in batches pre-slaughter (average age 20 weeks) and RRvol measured to investigate breed and sire effects. Genetic analysis of RRvol measured in 806 Texel ram lambs (∼20 weeks of age) from the UK’s national breeding programme was undertaken to estimate genetic parameters. Key results SBF lambs had reticulo-rumen volumes 30% larger on average than those of TEX (P

Introduction/Objective Sepsis is a global health priority and is often accompanied by a transient immune paralysis, associated with impairment in innate and adaptive immunity leading to progressive immunosuppression and higher susceptibility to secondary infections. Reactivation of Cytomegalovirus (CMV) occurs frequently and has been associated with adverse outcomes even in immunocompetent patients, with sepsis. Study objective was to evaluate the association between incidence of CMV reactivation and immune alteration in sepsis-induced immunosuppression in patients with prolonged sepsis. Methods Prospective observational study, which included consecutive patients admitted to hospital ICU, with severe sepsis and length of stay > 48 hours. Patients with other causes of immune-suppression and anti-CMV treatment were excluded. Blood samples were collected on enrolment and further weekly until 21 days or death/discharge. Quantification of CMV viremia was done using RT-PCR (qPCR). Markers used to evaluate immune suppression using Flow Cytometry were i) lymphocyte subsets (CD3+,CD19+,CD16+CD56+,CD4+,CD8+ and regulatory T cells - CD25+ CD127-), ii) surface receptor expression of HLA-DR on monocytes, and Programmed Death marker expression (PD-1) on T lymphocyte, iii) Measurement of pro-inflammatory(IL-6,TNF-a,IFN-g) and anti-inflammatory cytokines(IL-4,IL-10) by Cytometric Bead Array (CBA) assay. Results A total of 25 CMV IgG positive patients and 11 healthy controls were analyzed. CMV reactivation occurred in 20 patients. Median time for reactivation was 7 days. Patients with CMV reactivation had significant T-cell lymphopenia (p Conclusion Our study evidence suggests that monitoring lymphocyte subsets, PD-1expression on T lymphocyte, and levels of IL-6/IL-10 using flow cytometry, may serve as indicators for reactivation of CMV. Individualized immune therapy such as PD-1 receptor blockade drugs can be used to optimize treatment of patients with severe sepsis.

Pigs with a lean genotype were fed diets differing in protein and amino acid contents between 40 and 115 kg live weight. A high protein control regime (C) was compared with one supplying 11% less total protein but the same essential amino acid levels (LP1) and one supplying 16% less protein but lower amino acid levels (LP2). Regime LP2 produced fatter pigs in terms of subcutaneous, intermuscular and intramuscular fat (IMF), the latter measured in longissimus and semimembranosus muscles. The percentage of linoleic acid was lowest and that of oleic acid highest in IMF from LP2 pigs (11.57 and 34.59% respectively in longissimus). Pigs in regime LP1 had more longissimus IMF than C but similar semimembranosus IMF although both muscles had lower percentages of linoleic acid in LP1 than C, suggesting a tendency towards greater fat deposition in LP1. The high IMF content in LP2 produced the most tender, juicy steaks.

The effects on compositional changes across the growing-finishing period (40-115 kg) of feeding pig diets with different protein and amino acid levels were investigated using CT scanning (at 60, 85 and 115 kg live weight). Pigs of a lean commercial genotype were fed a commercial control regime (C), or a low protein regime with either high (LP1) or low (LP2) essential amino acid levels, all balanced for net energy. In vivo CT measurements agreed well with post-slaughter sample joint dissection results for carcass tissue weights/proportions, and CT-measured muscle density predicted intramuscular fat accurately. Pigs on C and LP1 regimes did not differ significantly in composition during growth. However, pigs on the LP2 regime had significantly more fat (in carcass, internal and intra-muscular depots) and less muscle, from 85 kg onwards. Although fat levels differed depending on diet regime (LP2>others), proportions of fat in different body depots were unaffected.

The Texel Muscling QTL (TM-QTL) is a QTL affecting loin muscling in Texel sheep with a paternal polar overdominant pattern of expression. This study on purebred Texel sheep used the first available data to include homozygote TM-QTL carriers in addition to homozygote non-carriers and both heterozygotes to assess the effect of TM-QTL on live weight throughout growth from birth to slaughter (at around 20 weeks of age) and carcass weight. TM-QTL was found to have an effect on most measures of live and carcass weight. Animals inheriting two copies of TM-QTL showed an increase of 1.5 kg or 9% in carcass weight and an increase in live weight across a range of ages from birth to slaughter of between 7 and 15% compared to animals carrying no copies of TM-QTL. The effect of TM-QTL on the weight traits studied appears to be additive but heterozygote weights did not always support this. If more data on lambs carrying TM-QTL become available in future it would be useful to validate this effect on live and carcass weight and the pattern of the effect.

Genotype by environment interactions (G × E) can form a potential source of inefficiency in animal breeding if selection decisions are made without acknowledging their effects. The presence of such interactions between two Scottish hill farms was investigated using performance data collected from 18,459 Scottish Blackface lambs between 1997 and 2010. Pedigree information was available for 27,548 animals. 30 out of 379 sires used during this time period were used on both farms. Farm A is located on the East Coast of Scotland, whereas Farm B is on the West Coast. The farms differ in a number of aspects including annual rainfall, topography, vegetation, temperature and altitude ranges, with Farm B representing a harsher environment overall. Traits studied were birth weight, 8-week weight and weaning weight, ultrasound back-fat and muscle depths at weaning, carcass weight, carcass fat grade and carcass conformation score. Genetic correlations were estimated for each trait, between the two farms, with those significantly different from 1 ( P s.e. 0.31). By taking G × E into account and comparing bivariate and univariate analyses, the maximum selection response observed for birth weight was 0.0016 kg per generation. Overall, the lack of G × E observed for the majority of traits studied suggest that the common sire offspring have performed similarly across both farms. However, the presence of G × E associated with birth weight may have implications for lambing associated problems, or lamb survival, if sires produce lambs with unexpectedly high or low birth weights.

The c.*1232G > A (MM) mutation in the myostatin gene and TM-QTL are two muscle-enhancing polymorphisms found on Chr 2 and Chr 18, respectively, in Texel sheep. Previous studies on purebred lambs and crossbred lambs out of Mule ewes showed that MM was associated with increased muscle mass and decreased fat content whereas heterozygous TM-QTL lambs had increased loin muscle ( M. longissimus lumborum , MLL) depth as measured by ultrasound and increased MLL weight. Welsh Mountain ewes, like Mule ewes, contribute significantly to UK slaughter lamb production from the UK sheep industry's stratified structure. Therefore, this study aimed to evaluate the direct effects of MM and TM-QTL in the genetic background of Texel × Welsh Mountain lambs. Four Texel sires, all MM carriers and two TM-QTL carriers, were used to inseminate Welsh Mountain ewes. Of the 175 lambs born, 130 could be classified for TM-QTL genotype [107 non-carriers (+/+), 23 heterozygous carriers (TM/+)] and 172 for MM genotype [15 non-carriers (+/+), 129 heterozygous carriers (MM/+), 28 homozygous carriers (MM/MM)]. All lambs were weighed at 8 and ∼23 weeks of age and were ultrasound scanned before being slaughtered at ∼24 weeks of age. All carcasses were graded for conformation and fat class, based on Meat and Livestock Commission (MLC) classification scores, and then scanned using a video image analysis (VIA) system to predict weight of carcass primal cuts and trimmed primal cuts, muscularity traits and carcass shape traits. Carrying two copies of MM was associated with a significant positive effect on 8 weeks weight, a negative effect on ultrasound fat depth and a substantial decrease in MLC-fat score. Two copies of MM also had a strong positive impact on VIA-estimated weight of the hind leg, chump and loin primal cuts, as well as the muscularity of the hind leg and loin regions with greater loin muscle width, depth and area. Homozygous MM carrier lambs had significantly wider carcasses across the shoulders, breast and hind legs and greater areas of the back view of the carcass when measured by VIA. Leg and carcass compactness were also significantly associated with the presence of two copies of MM. However, lambs carrying a single copy of MM were not significantly different to non-carriers in any of the traits measured. TM-QTL significantly increased ultrasound muscle depth and TM-QTL carriers had significantly greater loin muscle width and area measurements. Carcass weight did not differ significantly between genotypic classes for MM or TM-QTL. These results agree in general with other reports of the effects of MM and TM-QTL, in both direction and magnitude, on carcass traits.

This study evaluated the effects of the ovine c.*1232 G > A myostatin mutation (MM) on carcass traits in heterozygous crossbred lambs sired by Texel and Poll Dorset rams using ultrasound, CT scanning, carcass classification and VIA. In experiment 1, MM was associated with increased loin depth (+ 2.8%) and area (+ 3.2%). MM-carriers had significantly higher CT-estimated lean weight and proportion (2 to 4%) and muscle to bone ratio (by ~ 3%), in both experiments, and muscle to fat ratio (28%) in experiment 2. Muscle areas in three cross-sectional CT scans, were higher (2 to 5%) in MM-carriers. In experiment 2, fat-related measurements were significantly lower in MM-carrier lambs but this was not seen in experiment 1. A significant increase in muscle density, indicative of lower intramuscular fat, in MM-carriers shows that meat quality characteristics need attention. Carrying MM significantly decreased carcass fat scores. VIA did not detect any significant MM effects.

A quantitative trait locus (QTL) has been identified on chromosome 18 in Texel sheep (TM-QTL) that increases depth and area of the longissimus dorsi muscle. The study aimed to assess the pleiotropic QTL effects on key meat quality traits (toughness and intramuscular fat content after >or=7 days aging) of crossbred lambs carrying one copy of the TM-QTL. The results showed that male TexelxMule lambs carrying the TM-QTL had significantly less intramuscular fat (1.86% versus 2.25%) and higher toughness, with increased variation, in the loin muscle, compared to non-carrier males. Similar conclusions were obtained using two different types of tenderometer equipment: one using the Volodkevitch test (average shear force of 4.17 kgF or 40.9N for carrier males, 2.61 kgF or 25.6N for non-carrier males) and one using the MIRINZ test (average shear force of 6.18 kgF or 60.6N for carrier males, 5.22 kgF or 51.2N for non-carrier males). Although most toughness measurements were within published consumer acceptability limits, a few individual TM-QTL carrier lambs had unacceptably tough meat, despite enhanced post-slaughter processing. The TM-QTL did not significantly affect loin toughness in female lambs, leg toughness in either sex, or intramuscular fat content. These results should be considered, alongside direct effects of the TM-QTL on muscling and carcass composition, in recommendations for the use of this QTL by sheep breeders.

Various post-mortem measurements (carcass weights, conformation and fatness classes, external carcass dimensions, eye muscle dimensions, subcutaneous fat depth, pH and temperature) were recorded on 197 Texel (TEX) and 200 Scottish Blackface (SBF) lamb carcasses. The potential use of these measurements to predict carcass composition and key meat quality traits was investigated, to enable categorisation of carcasses in the abattoir and/or for use in genetic improvement programmes. By combining different measurements, accurate predictions of dissected carcass muscle weight (adjusted R(2) 0.93 in TEX, 0.88 in SBF) and fat weight (adjusted R(2) 0.84 in TEX, 0.87 in SBF) were achieved, and moderate predictions of intra-muscular fat (adjusted R(2) 0.56 in TEX, 0.48 in SBF), whilst shear force was predicted with low to moderate accuracy (adjusted R(2)

Texel muscling quantitative trait locus (TM-QTL) is a QTL on chromosome 18, originally identified in purebred UK Texel sheep, which was reported to increase ultrasonically measured muscle depth at the third lumbar vertebra by around 4% to 7%. The objective of the present study was to comprehensively evaluate the TM-QTL and to determine whether it could provide benefits to the UK sheep industry through increased carcass meat yield in crossbred slaughter lambs. Effects of this QTL on a range of carcass traits, including those measured in vivo and by dissection, were evaluated in heterozygous carrier and non-carrier lambs produced by crossing heterozygous carrier Texel rams with non-carrier Mule (Bluetaced Leicester x Scottish Blackface) ewes from a lowland flock. The TM-QTL was found to increase loin muscling in crossbred lambs at a given live weight or carcass weight as measured by ultrasound, X-ray computed tomography (CT) and carcass dissection. Depth of M. longissimus lumborum (MLL) was greater in TM-QTL carrier lambs compared to non-carriers as measured by both ultrasound at the third lumbar vertebra (+43%, P = 0.033) and CT scanning at the fifth lumbar vertebra (+6.7%; P = 0.004). Width and area of MLL measured using CT were also greater in TM-QTL carrier lambs compared to non-carriers (+3.09%; P = 0.013 and + 5.1%; P = 0.047, respectively). Loin muscle volume measured using CT was greater in TM-QTL carriers than in non-carriers (+5.9916; P = 0.005) and the dissected weight of the MLL was + 7.1% greater in TM-QTL carriers compared to non-carriers (P < 0.001). The proportion of the total carcass lean meat yield (LMY) that was contained within the loin region was slightly higher in TM-QTL carriers than in non-carriers (0.154 v. 0.145; P = 0.006). However, TM-QTL was found to have no significant effect on the total weight or proportion of LMY or of saleable meat yield in the carcass measured by dissection, or on muscling in the hind leg measured by CT or dissection. This work has verified that the inheritance of TM-QTL is associated with increased loin muscling in crossbred lambs, as has previously been reported for purebred Texel lambs.

This study investigated associations of prion protein (PrP) genotype with body composition and weight traits of Scottish Blackface ewes. Body composition was predicted using computer tomography (CT) scans to estimate muscle, carcass fat, internal fat, and bone weights. The traits were measured at 4 key seasonal production points (pre-mating, pregnancy, midlactation, and weaning) over 4 production cycles (2 to 5 yr old). There were 2,413 records for each of the CT traits measured on 335 ewes, and 26,649 records for each of the body condition score and BW traits for 2,356 ewes. From 1999 to 2004, animals were genotyped to determine polymorphisms at codons 136, 154, and 171, which are associated with scrapie susceptibility. Four alleles were found in the population (ARR, AHQ, ARQ, and VRQ). The data were analyzed using a linear mixed random regression model assuming that the direct additive genetic effect was a 2nd order Legendre polynomial function of time. The PrP genotype was included in the model as a fixed effect along with other fixed factors with significant effects (P < 0.05). Five separate analyses were carried out for each trait, depending on the method of classifying the PrP genotype. In the first analysis, animals were categorized according to the genotype. Only the 5 most common genotypes (ARR/ARR, ARR/AHQ, ARR/ARQ, AHQ/ARQ, and ARQ/ARQ) were included. In the last 4 analyses, animals were categorized according to the number of each PrP allele carried. For CT traits and body condition score, results showed that the PrP genotype has no association with the overall mean of the traits (averaged over age). For BW, ewes without the ARQ allele were at least 0.5 kg heavier than ARQ homozygous and heterozygous ewes. On the other hand, there was a significant interaction between PrP genotype and age of the ewe (i.e., the effect of PrP genotype was not the same at different ages for 5 out of the 6 traits studied). In general, ARQ carrying ewes mobilized more fat reserves at times of nutrient deficiency, such as during lactation, and gained it back more quickly by the mating season (when nutrients became abundant) than non-ARQ carriers. Therefore, selecting against this allele would have consequences on BW and seasonal mobilization of body reserves. The number of VRQ alleles (the most scrapie susceptible allele) carried was not significantly associated with any of the traits.

Differences in muscularity of the hind leg (HL) and lumbar region (LR) were investigated between sexes (ram vs ewe lambs), breeds (Scottish Blackface, SBF vs Texel, TEX) and progeny of high- and low-muscularity sires (HM, LM) (n=471). The influence of these factors on meat eating quality (MEQ) was also examined (n=229). TEX lambs had 16% greater muscularity than SBF in both regions, whilst differences between sire groups were 4%. Ewe lambs had slightly higher values of muscularity for the HL than rams, but values were similar for the LR. Meat from SBF lambs had higher tenderness, stronger lamb flavour and higher overall liking than TEX meat. Sex had a weak influence with ram lambs having a stronger abnormal flavour and lower overall liking in the LR only. No significant differences in MEQ were found between HM- and LM-sired lambs, suggesting that improvements in muscularity would not have unfavourable effects on MEQ.

A multi-trait selection index designed to improve the overall economic performance of hill sheep, inducting both maternal and lamb traits, has been developed and tested in a selection experiment over 7 years. Two versions of the index were tested, with different economic weights applied to the traits, on two different hill farms: one version including maternal and growth traits; the other version with additional breeding goals of carcass weight, fatness and conformation scores. Responses to selection, using both versions of the index, suggest that improvements are being made in overall index score and lamb growth. This study investigated the indirect effects of these selection indices on lamb carcass composition and muscularity traits, as measured using X-ray computed tomography (CT) scanning. A total of 499 lambs from the two hill farms were CT scanned at weaning (approximately 120 days of age). Approximately half of the lambs from each farm were from the selection line (S, animals with highest index scores selected for breeding), while the other half were from a control line (C, animals with average index scores selected). Composition and muscularity traits were estimated on each lamb from CT data and differences between genetic lines investigated within farm, using restricted maximum likelihood analyses, adjusting for either live weight or age. Results showed that the selection index without carcass traits produced lambs with carcass composition that was not significantly different to control lambs at a given live weight or age. Including carcass traits in the index resulted in lambs with no compositional differences (except for a slight increase in bone) at a set age compared with controls. At a given live weight however, selection lambs had less fat and lower carcass weights and killing-out percentage. Muscularity (3-D muscle shape) and muscle area shape (2-D) were not improved as a result of selection on either version of the index (including carcass weight and grades in the breeding goals or not) and, at a fixed live weight, muscularity in hind leg and lumbar regions tended to be higher in the C line. To accelerate changes in carcass composition and muscularity within the context of a multi-trait selection index for hill sheep, consideration should therefore be given to including objective CT-derived carcass traits in the index in addition to the Meat and Livestock Commission (MLC) carcass grades or ultrasound measurements.

Assessments of muscle mass and skeletal dimensions by Computed Tomography (CT) enable the development of new muscularity indices for the hind leg (HL) and lumbar region (LR) in lambs. Compared to previous CT muscularity indices, the accuracy was much higher with the new index in the HL (correlations between CT and dissection indices of 0.89 vs 0.51). The accurate measurement of femur length by CT used in the calculation of the new HL index made an important contribution to the higher accuracy of the index. The improvement in accuracy was smaller for the LR (0.55 vs 0.44). The association of CT muscularity indices and carcass quality in Texel and Scottish Blackface lambs showed that improved muscularity is not phenotypically correlated with detrimental effects on carcass composition. CT muscularity indices provide an alternative method to improve carcass conformation and leanness, using measurements that at a constant weight are independent of fatness.

Male and female Texel (Tex, n = 130) and Scottish Blackface (SBF, n = 103) lambs were grazed together on low-ground pastures from birth to slaughter. Lambs were scanned using computer tomography (CT) on a maximum of four occasions during the growth period: at approximately 8, 11 and 16 weeks of age and pre-slaughter, which occurred in five batches over a 12-week period. The aim was to investigate the use of in vivo CT scanning over the growth period (from ca. 15 to 45 kg live weight, corresponding to an age of ca. 40 to 200d) to study changes in carcass traits and their relationships during growth, in two contrasting breeds. Relationships among CT traits and between CT traits and live weight were investigated within breed, to assess changes with growth. Increased live weight was associated with increases in total fat proportion, fat:muscle ratio, muscle:bone ratio, loin muscle area and proportion of fat in the chest region, in both breeds. Two-dimensional muscle shape (depth:width ratio) in the hind leg (HL S ) and the loin (LM S ), and proportion of muscle in the loin also increased with live weight in Tex lambs. Live weight was negatively associated with proportion of fat in the leg in both breeds, and with HL S , LM S and CT fat density in SBF lambs. Similar trends between CT traits and total fat proportion suggest that associations hold for increasing maturity, as well as size. The results suggest that slaughtering SBF lambs at lighter weights will avoid them becoming over-fat, maintain overall muscle proportion at a higher level and lead to rounder muscle shapes in the hind leg and loin. However, Tex lambs can be slaughtered at heavier weights without becoming over-fat, and this will result in a higher proportion of muscle being deposited in the economically important loin area, and the muscles in the loin and hind leg being rounder in cross-section. CT scanning lambs during growth allows accurate composition and muscle shape measurements on large numbers of lambs at different stages of development and can help understand the developmental patterns of different economically important sheep breeds. This knowledge can aid in management decisions to improve carcass quality at slaughter. Further work is now needed to examine the genetic background to the relationships between traits presented in this study, and their changes with growth, to allow the incorporation of such CT traits into selection programmes for different sheep breeds.

This study compared the use of various models to describe growth in lambs of 2 contrasting breeds from birth to slaughter. Live BW records (n = 7559) from 240 Texel and 231 Scottish Blackface (SBF) lambs weighed at 2-wk intervals were modeled. Biologically relevant variables were estimated for each lamb from modified versions of the logistic, Gompertz, Richards, and exponential models, and from linear regression. In both breeds, all nonlinear models fitted the data well, with an average coefficient of determination (R 2 ) of >0.98. The linear model had a lower average R 2 than any of the nonlinear models ( 0.92). Selection on growth variables seems promising (in Texel more than SBF), but high genetic correlations between variables may restrict the possibilities to change the growth curve shape. A random regression model was also fitted to the data to allow predictions of growth rates at relevant time points. Heritabilities for growth rates differed markedly at various stages of growth and between the 2 breeds (Texel: 0.14 to 0.74; SBF: 0.07 to 0.34), with negative correlations between growth rate at 60 d of age and growth rate at finishing. Following these results, future studies should investigate genetic relationships between relevant growth curve variables and other important production traits, such as carcass composition and meat quality.

Two selection indexes, one intended for lamb producers and finishers and one for store lamb producers, were derived using genetic parameters for carcass and maternal characteristics from Conington et al. (2001) and economic values from Conington et al. (2004). This paper summarizes responses to selection for lamb traits only, after 5 years of selection (1998 to 2003) on two farms using these selection indexes. The index for lamb producers and finishers, evaluated on farm 1, with a flock size of 680 ewes, includes economic weightings for maternal traits as well as carcass weight, fat and conformation grades, whereas the index for store lamb producers, evaluated on farm 2, with a flock size of 580 ewes, only includes economic values for maternal traits and lamb growth to weaning. Three selection lines of Scottish Blackface sheep per farm were created with the first lambs born to each line in 1999. These lines were selection (S), control (C) and industry (I); they were of equal size on each farm. Five top- and five average-performing ram lambs were selected each year for the S and C lines respectively using a multi-trait best linear unbiased prediction (BLUP) implementation of the indexes. The I-line used four mature rams bought from industry, selected on appearance only, i.e. adherence to breed ‘type’. Results showed that 5 years after the implementation of the index, the S line had significantly higher index scores than the C or I lines on both farms. The means (s.d.) for the average index scores in 2003 are 114 (328), 119 (371) and 451 (328) (farm 1), and −8 (146), −11 (130), and 250 (129) (farm 2) for the C, I and S lines, respectively, giving predicted net differences (S-C) of £3·38 (farm 1) and £2·58 (farm 2) per ewe. Phenotypic responses showed significant S v. C differences in weaning weight on both farms. As predicted from previous analyses, no changes in carcass quality traits were seen at farm 1 although S-line carcass weights tended to be heavier than those from the C or I lines. The results show that genetic improvement using multi-trait selection indices has been successful and it is a viable, long-term strategy to improve levels of production for hill sheep in extensive environments.

This study investigates the accuracy of an automatic image analysis method that was developed for spiral computed tomography scans (SCTS), with the objective of calculating the volume of muscle in the hind leg (HLMVCT) and lumbar region (LRMVCT) in lambs. The first step in the image analysis method was the isolation (segmentation) of the muscle regions in each image of the SCTS, using a new program that was implemented in the Sheep Tomogram Analysis Routines software (STAR). Due to the differences of muscle shape in the regions investigated, the new segmentation program applies different segmentation paths in specific subregions. These were automatically identified by the program based on skeletal landmarks. After the segmentation was completed, the muscles areas were automatically measured by counting the pixels representing muscle in each image; the volumes were calculated by adding the muscle areas of each image multiplied by the depth of the image (inter-slice distance). The accuracy of these measures of muscle volume was evaluated, using regression analysis, by comparing HLMVCT and LRMVCT to the hind leg and lumbar region muscle weights measured after dissection (HLMWD, no. =240, and LRMWD, no. =50, respectively) of Texel (TEX) and Scottish Blackface (SBF) female and male lambs slaughtered in 2003-04. The effects of breed, sex and year on the association (SCTS v. dissection) were evaluated. There was a strong association between HLMVCT and HLMWD ( R2=97·4%), which only increased slightly ( R2=97·7%) when breed was included in the model. This indicates that HLMWD can be estimated directly from HLMVCT with a high degree of accuracy. For the lumbar region, the association was high ( R2=83·0% to 88·8% depending on the model) but lower than in the hind leg, probably because the automatic segmentation isolates only the areas of the longissimus lumborum and multifidi muscles. Breed had a significant effect on the prediction of LRMWD from LRMVCT, as well as sex in the case of the TEX lambs. The results indicated that the predictions of LRMWD from LRMVCT require different equations for very divergent breeds such as TEX and SBF.

From a calibration trial involving computer tomography (CT) scanning and dissection of 45 lambs, a prediction equation was derived to estimate total internal fat weight in Scottish Blackface lambs from measurements taken on cross-sectional CT images. Using data from two cross-sectional images (at the hip and loin) internal fat can be predicted with relatively high accuracy (adjusted R(2) = 62.2%, r = 0.79). The derived equation was then used to predict internal fat weights in a further 427 Scottish Blackface lambs from a separate trial. Phenotypic correlations were calculated between predicted internal fat weight and weights of total carcass fat, muscle and bone, predicted using previously derived equations. When considering absolute tissue weights, adjusted for fixed effects, internal fat showed the strongest positive correlation with carcass fat (0.58), followed by muscle (0.36), and then by bone (0.32). When tissue weights were adjusted for fixed effects and total carcass weight (so considering tissue weights relative to size), internal fat showed a lower correlation with carcass fat weight (0.36) and negative correlations with muscle (-0.35) and bone (-0.19). These results provide the basis for more complex studies of relationships (phenotypic and genetic) between internal fat in hill lambs and economically important traits, such as carcass composition and survival of lambs, and tissue levels in different depots in hill ewes.

Hill ewes undergo large changes in body fat and muscle weight throughout the annual production cycle as they contend with the pressures of reproduction and lactation, as well as harsh environmental conditions. This study modelled seasonal changes in fat and muscle weights in Scottish Blackface hill ewes throughout their productive lifetime using random regression statistical techniques.Scottish Blackface ewes (no. = 308) were scanned using computed tomography (CT) four times per year, from 2 until 5 years old. Heritabilities of tissue weights were estimated at 2-weekly intervals throughout the productive life of the ewe. Genetic correlations between tissue weights at the same point in the production cycle at different ages, and between tissue weights at different events within each annual production cycle were predicted. Animal solutions from random regression analyses were used to estimate tissue weights, from pre-mating at 2 years old to weaning at 5 years old. The effects of litter size in the current and previous production years on fat and muscle weights were investigated.Correlations between CT tissue weights and those predicted by a sin/cos random regression model were 0.87, 0.84, 0.88 for carcass fat, internal fat and muscle respectively. Heritabilities ranged from 0.31 to 0.90 for carcass fat weight, 0.21 to 0.68 for internal fat weight and 0.26 to 0.57 for muscle weight, throughout the productive lifetime of the ewe. Heritabilities were highest during mating for fat weights, and during the dry period and lambing time for muscle weights. Heritabilities of tissue weights in 3-year-old ewes were higher than in other age groups. Genetic correlations were 1.00 between tissue weights at the same scanning event at different ages, but ranged from close to zero to 0.97 between scanning events within age groups. Clearly environmental variation across time was large. The number of lambs produced in both the current and the previous year influenced tissue levels. Ewes that did not produce lambs (barren) in a given year carried more muscle during that year than ewes producing lambs. As ewes aged, barren ewes carried increasingly more carcass fat and muscle than ewes with lambs. Barren ewes also had significantly more muscle during the following year than ewes that had weaned lambs. Ewes that reared twins had significantly less carcass fat the following year than singleton-bearing or barren ewes. These effects of previous litter size increased significantly with age.

Non-cage systems for housing laying hens often incorporate a framework of perches, allowing birds to move in three dimensions. Wood is predominantly used for perch construction, because it is relatively cheap and easy to work with. However, wooden perches are difficult to clean and disinfect, which could lead to disease and discomfort for the birds using them. The objectives of this study were to identify which characteristics of perch design are preferred by laying hens; and to test whether birds would use perches of alternative materials for a comparable amount of time as they use wooden perches. Six laying hens were housed individually in litter-floored pens and were offered a choice of three pairs of contrasting perch types (experiments 1-3): a rectangular, wooden perch (‘control’) versus two, thin, parallel, rectangular wooden perches; ‘control’ versus a similar perch covered with foam and fabric; and ‘control’ versus a round, wooden perch. Birds were given each pair of perches twice, controlling for perch position in the pen. Time spent on each perch in a 48h period was determined from video records. Preferences were then tested in consecutive trials (experiments 4-5) between perches of the following materials: wood versus plastic versus steel; and wood versus textured aluminium. There were no significant differences in time spent on different perches, suggesting that birds had no preferences between perch types. The implications of these results could be important for the design of alternative systems for laying hens. Birds may be content to perch on artificial materials which could be more hygienic than wood and easier to maintain in a commercial system.

All end-of-lay hens must be transported from the production site to the site for slaughter, usually by road. The acts of being crated and transported are likely to be novel and potentially frightening. Frightened birds can be put into tonic immobility (TI), an unlearned, catatonic state, the duration of which is positively related to the fear level of the birds. Ninety ISA Brown free-range birds (in three groups of 30) and 90 caged ISA Brown birds (in similar groups) were transported (one group from cages and free-range per day) on a journey of 68 km (74 min approximately). On their return, each of the birds was subjected to TI. Although no significant differences were recorded between free-range and caged birds after they were transported (P = 0.087), in the comparison between the same birds after 7 wk, without transport, a significant difference in fear levels was observed (P < 0.001). The free-range birds were less frightened than the caged birds. No significant difference was ever found in fear levels for caged birds from different tiers. Handling and transport on this relatively short journey was apparently equally frightening for caged and free-range birds. It cannot be assumed that just because fear levels differ between free-range and caged birds, this difference will be apparent for all novel stimuli. If all birds, at all tiers, receive the same amount of human contact during the production period, there is no reason to expect differences to occur in fear levels of birds from different tiers.

Research into the responses of hens on perches is important in order to assess the welfare impact of alternative systems for egg production which incorporate perches in their design. Previous studies suggest that many flight and landing accidents occur in such systems as birds attempt to move between perches and facilities, resulting in a high incidence of bone breakage. In this study three horizontal perches were set with a gradient between them of 0, 30, 45 or 60 degrees according to treatment. Four groups of 15 ISABrown laying hens were individually exposed to each treatment, being placed on the uppermost perch (Perch 1) with a food reward available at the lowest perch (Perch 3). Behaviours performed before reaching Perch 3 were recorded over time. More birds failed to move to Perch 3 in 10 minutes when perches were separated by 45 or 60 degrees. In birds which stayed on the perches for the full 10 minutes, without reaching Perch 3, downward head movements, calling, intended jump behaviours, side-stepping and wing-flapping decreased significantly with time spent on the perches. Motivation to complete the task, in order to gain the food reward, was high in all treatments. However, when birds found perches difficult to negotiate, behaviours indicating intention to move to the food decreased with time and the incidence of behaviours indicating frustration and thwarting increased. In non-cage systems such frustration could reduce bird welfare.

Stockworkers should be able to easily manage alternative systems for commercial egg production. Such production systems can be analysed in terms of human welfare, based on ergonomic criteria. Work-related postures can cause discomfort and strain to workers (Stoffert, 1985). The OVAKO Working posture Analysing System (OWAS) developed in 1974 (Karhu et al, 1977) defines body positions during working practices and scores them according to the strain caused. This technique has so far not been used to assist in the design of working systems for the poultry industry. This pilot study was carried out to determine if such a technique could be easily applied to a perchery system and whether it could lead to an improved design. The stockworker was video recorded performing normal duties within the perchery and the positions of the body were assessed, using the OWAS system. It was found that manual collection of floor eggs and reaching into the middle of the perches from the litter side put the most strain on the stockworker. Modification of the perchery, in light of these results, will establish an improved perchery system for the stockworkers.

Implementing the use of spine traits in a commercial breeding program has been seen to improve meat production from the carcass of larger-bodied pigs. The aim of this study was to assess the extent of variation in spine characteristics within and between breeds of sheep and to investigate the association with body length and tissues traits to deliberate if a similar approach could be applicable in the sheep sector. Spine traits (vertebrae number, VN; spine region length, SPL; individual vertebra length, VL) of the thoracic (THOR) lumbar (LUM) and thoracolumbar (T+L) spine regions were measured using x-ray computed tomography (CT) on 254 Texel (TEX), 1100 Scottish Blackface (SBF), 326 Texel cross Mule (TEX × MULE), and 178 Poll Dorset cross Mule (PD × MULE) lambs. Simple descriptive statistics inform that variation in thoracolumbar VN exists within all breeds and crosses; TEX animals showed the largest range of variation in thoracolumbar VN (17 to 21) and the TEX × MULE the smallest (18 to 20). Significant differences were not observed between sexes, but did occur between breeds (P0.05), which is indicative of a genetic basis for these traits. Least-squares means identified that TEX had the least thoracolumbar VN (19.24) and SBF possessed the most (19.63); similarly the lowest measures for SPL and VL for each spine region were observed in TEX, but the greatest values for these traits were expressed predominantly in the crosses (TEX × MULE and PD × MULE). Correlation coefficients (r) within each breed or cross support the interpretation of additional vertebrae contributing to a longer length of the spine region in which they occur (P0.001; e.g., for PD × MULE lambs), r between traits VNTHOR and SPLTHOR (r = 0.59), VNLUM and SPLLUM (r = 0.94) and VNT+L and SPLT+L (r = 0.65) all reach moderate to very high values. In all breeds and crosses, this relationship is particularly strong for the lumbar region. The few significant (P0.05) correlations observed between spine and tissue traits [CT-predicted quantities of carcass fat and muscle (kg) and area of the LM (mm(2))] indicated no substantial relationships, r was small (ranging from -0.25 to 0.19) in each case. To conclude, significant vertebral variation exists within and between sheep breeds and crosses, which can contribute to an increase in body (and carcass) length. Including measurements taken for other primal cuts will further aid in assessing any potential increase in meat production from these longer-bodied sheep.

A quantitative trait locus (QTL) for increased loin muscularity (TM-QTL) has previously been identified in purebred Texel sheep. Crossbred lambs born out of Mule ewes mated to heterozygous Texel sires for the TM-QTL were evaluated for a range of carcass traits. Lambs were genotyped and classified as carriers (n = 62) of a single copy of the TM-QTL and non-carriers (n = 49). In this study, the effects of the TM-QTL on carcass attributes were investigated using subjective classification scores for conformation and fatness, and measurements from a video image analysis (VIA) system. In addition, refined prediction equations to estimate weights of primal joints (leg, chump, loin, breast and shoulder) were obtained by calibrating the VIA system against computer tomography (CT) measurements in the loin region. The new refined prediction models increased the accuracy of prediction of all primal cuts on an average of 16% compared to previously derived standard VIA prediction equations. The coefficient of determination (R2) of the VIA system to predict in vivo CT measurements ranged from 0.39 to 0.72 for measurements of Musculus longissimus lumborum (MLL) area, width and depth, lumbar spine length, loin muscle volume and loin muscularity index. Using VIA estimates of CT-measured loin muscle traits, a significant increase in depth (+2.7%) of the MLL was found to be associated with the TM-QTL. Conformation and fatness scores and the shape of the carcass measured as individual lengths, widths and areas by VIA were not significantly influenced by the TM-QTL. Primal meat yields estimated using both standard and refined VIA prediction equations were not significantly affected by the TM-QTL. However, carcass ‘compactness’ was found to have significantly increased in carrier lambs. The weight of the dissected MLL estimated using VIA information was greater (+2.6%) for carriers compared to non-carriers. To conclude, neither the current industry carcass evaluation system for conformation and fatness nor the standard VIA system is able to identify the effect of the TM-QTL in the loin region in the moment. However, the calibration of the VIA system against CT measurements resulted in improved VIA prediction equations for primal meat yields and also showed moderate potential to estimate loin muscle traits measured by CT and to detect, partially, the effect of the TM-QTL on these traits.

Genetic parameters were estimated between current UK hill sheep breeding goals and lamb carcass composition and muscularity traits derived using X-ray computed tomography (CT). To produce these estimates, a total of 648 lambs from two hill farms were CT scanned at weaning (ca 120 days of age), over 3 years, and total weights of carcass muscle (MUSC), fat (CFAT) and bone (BONE) and internal fat (IFAT) were predicted. Previously derived muscularity indices were also calculated for the hind leg (HLMI) and lumbar (LRMI) regions, to assess muscle shape. Data for current breeding goals (lamb performance and maternal traits) were also included from a total of 10 297 lamb records and 12 704 ewe records. Heritabilities were estimated for each trait and genetic and phenotypic correlations were calculated between each CT trait and other lamb or ewe traits. Moderate to high positive genetic correlations were found between CT-predicted tissue weights and breeding goals, which were also weights (lamb weaning weight, carcass weight, mature ewe weight, average weight of lambs reared by the ewe). CFAT was positively genetically correlated with ultrasound backfat depth at weaning (UFD) and subjective fatness grade at slaughter (MLCF), suggesting that carcass fat could be decreased using selection on any of these predictors. Ultrasound muscle depth at weaning (UMD) and subjective conformation score at slaughter (MLCC) had high genetic correlations with the muscularity indices (HLMI and LRMI), but correlations with MUSC were not significantly different from zero. This implies that selection to improve MLCC is likely to be increasing the 'roundness' of muscle shape in the high-priced carcass region, but having little impact on total lean meat yield. Correlations of CT traits with the other ewe traits (number of lambs weaned, number of lambs lost, longevity, fleece weight) were generally small or not significantly different from zero. The genetic parameters generated in this study can now be used in selection index calculations to assess the benefits of including lamb CT traits in future selection programmes for hill sheep.

Genotype by environment interactions (G×E) can form a potential source of inefficiency in animal breeding if selection decisions are made without acknowledging their effects. The presence of such interactions between two Scottish hill farms was investigated using performance data from 16,867 Scottish Blackface lambs collected between 1997 and 2009. Pedigree information was available for 25,970 animals and 24 of the sires used during this time period were used on both farms. Farm A is located on the East Coast of Scotland, whereas Farm B is on the West Coast. The farms differ in a number of aspects including annual rainfall, topography, vegetation, temperature and altitude ranges, with Farm B representing a harsher environment overall. Traits studied were lamb weight (LWT), ultrasound backfat depth (UFD) and ultrasound muscle depth (UMD) at weaning. To determine the level of G×E present for these traits, genetic correlations were estimated for each trait between the two farms. Heritabilities and correlations were estimated using univariate and bivariate analyses in ASREML based on a model that fitted relevant fixed effects and both direct genetic and maternal permanent environmental (c2) random effects. Moderate heritabilities, at each farm, were estimated for all traits; LWT - Farm A = 0.21 (0.03), Farm B = 0.27 (0.03); UFD - Farm A = 0.21 (0.02), Farm B = 0.26 (0.03); UMD - Farm A = 0.32 (0.03), Farm B = 0.35 (0.03). Estimates of c2 were low to moderate; LWT - Farm A = 0.16 (0.01), Farm B = 0.18 (0.02); UFD - Farm A = 0.09 (0.01), Farm B = 0.12 (0.01); UMD - Farm A = 0.08 (0.01), Farm B = 0.12 (0.01). Genetic correlations estimated between the two farms were not significantly different from 1. The lack of significance would suggest that no G×E exists for weaning weights or ultrasound tissue depths between the two farms in this study.

The aim of this chapter was to review the use of computed tomography (CT) in UK sheep breeding to improve carcass composition and elements of meat quality, as well as the use of CT scanning as a benchmarking system for faster and cheaper carcass evaluation for use both in practise for the livestock industry and for furthering research aims. This paper will review some of the work carried out at the Scottish Agricultural College (SAC) in collaboration with Biomathematics & Statistics Scotland (BioSS) in the last 14 years. The work investigated the use of CT scanning alongside ultrasound scanning (US) in a synergistic approach to benefit the UK sheep industry by improving the breeding value of terminal sire (meat) rams. In vivo measurements via CT of body composition of the top ranking male selection candidates (pre-selected by their US measured backfat and muscle depth) are used to enhance the accuracy of selection decisions regarding carcass quality and more recently, also some components of meat quality. CT-derived information provides both directly measured traits for use in the breeding process as well as serving as a bench-marking system for the validation of other techniques such as Video image analysis (VIA) or ultrasound scanning. It also has real potential to replace the “Gold Standard” of carcass evaluation which has always been used in past, which is the dissection of carcass tissues into component parts. Initially, we will characterise UK sheep breeding and the need to accurately and precisely measure body and carcass composition of breeding animals or their close relatives with the aim of improving the quality of slaughter lambs. UK sheep industry. There are around 15 million breeding ewes in the UK (www.defra.gov.uk/evidence/statistics/foodfarm/general/auk/latest/excel/index.htm), half of which are purebred and half are crossbred, with hill and lowland areas each containing around 40% of the ewes and upland areas the remaining 20% (Pollott & Stone, 2006). The UK sheep industry is characterised by a stratified structure, which has evolved over many years to best utilise the available land and to match breeds or crosses to different systems. The stratified system has different selection goals within each strata and makes use of specialised sire and dam breeds and crosses and exploits both the complementarities of breeds for crossing e.g. longwool (litter size, milk) x hill (hardiness, intermediate mature

Texel Muscling QTL (TM-QTL) increases loin muscling in lambs inheriting it from their sire only. This study investigated TM-QTL effects on meat quality in 209 Texel lambs that were CT-scanned then slaughtered at 20weeks (carcasses aged for ~1week). Loin meat quality traits included: CT-measured muscle density (predicting intramuscular fat); mechanical tenderness using Volodkevich-type jaws or MIRINZ tenderometer; intramuscular fat; sensory eating quality (sub-sample of 40 lambs). Volodkevich tenderness was also measured in the leg (Vastis lateralis). TM-QTL genotypes were determined, giving 40 non-carriers (+/+), 70 heterozygotes-53 inheriting TM-QTL from the sire (TM/+) and 17 from the dam (+/TM), 34 homozygote TM-QTL lambs (TM/TM) and 65 uncertain. Multiple regression identified no genotype effects on meat quality. For MIRINZ-measured loin tenderness only, contrasts revealed a significant additive effect of TM-QTL (1.27kgF difference between homozygotes). However, the taste panel identified no significant differences between +/+ and TM/TM lambs. Results show little evidence of TM-QTL affecting meat quality.

A Texel muscling quantitative trait locus (TM-QTL) has been identified on chromosome 18, which increases loin muscling, but may also have a negative impact on mechanically-measured loin tenderness in crossbred lambs, depending on conditioning time. This study investigated the influence of a range of conditioning times (3, 5, 7 or 9 days) on the effect of TM-QTL on loin muscle tenderness. Using Texel rams heterozygous for TM-QTL, mated to non-carrier Mule ewes, heterozygous (n = 45) and wild-type (n = 50) crossbred lambs were produced. Weight of the valuable Longissimus lumborum muscle was higher in TM-QTL carriers than non-carriers, when compared at a fixed age (+11.5%; P = 0.038), with the same trend at a fixed carcass weight (+10.2%; P = 0.064). Toughness, measured by shear force, was significantly higher in samples from TM-QTL carriers than non-carriers, after conditioning for 3 days (P = 0.002), 5 days (P = 0.003) or 7 days (P = 0.03), but was not significantly different after 9 days of conditioning (P = 0.32). Compared to non-carrier lambs, the proportion of samples above consumer acceptability thresholds for toughness was greater in the TM-QTL carrier lambs after 3 and 5 days of conditioning, similar at 7 days, but lower at 9 days. The results suggest that the negative effect of TM-QTL on loin tenderness in crossbred lambs can be overcome by conditioning for more than 7 days. Marketing of TM-QTL carrier lambs through companies that use enhanced processing protocols could be beneficial, due to higher loin muscle weights, without negative effects on meat quality. (C) 2010 Elsevier Ltd. All rights reserved.

10 páginas, 7 tablas., Ultrasound tissue depths, similar to those measured commercially as part of UK beef genetic evaluation schemes, were measured on 52 crossbred steers and 10 heifers at the start and end of the finishing period (average age 476 and 568 days, respectively). Animals were slaughtered at commercial target weights and carcass grades, and one carcass side fully dissected. Combining live weights and ultrasound tissue depths measured both before and after finishing provided the best predictions of carcass composition. Dissected fat weights and proportions in the carcass side, the forequarter and the hindquarter were predicted with high accuracy (R-2 similar to 0.8), muscle weights with moderate accuracy (R-2=0.5-0.6), but muscle proportions were less accurately predicted (R-2=0.23-0.49). Meat and Livestock Commission (EUROP) carcass conformation and fatness classes could also be predicted with moderate accuracy (R-2=0.4 and 0.6, respectively). Fat and muscle weights in each quarter expressed as proportions of the total weight of that tissue in the carcass side were not predicted accurately (R-2, Scottish Government.

LoinMAx (LM) is a quantitative trait locus (QTL), which was found to be segregated in Australian Poll Dorset sheep, and maps to the distal end of sheep chromosome 18. LM-QTL was reported to increase Musculus longissimus dorsi area and weight by 11% and 8916, respectively. The aim of this study was to comprehensively evaluate the direct effects of LM-QTL in a genetic background typical of the stratified structure of the UK sheep industry, before it can be recommended for use in the United Kingdom. Crossbred lambs, either non-carriers or carrying a single copy of LM-QTL, were produced out of Scottish Mule ewes (Bluefaced Leicester X Scottish Blackface) artificially inseminated with semen from two Poll Dorset rams that were heterozygous for LM-QTL. Unexpectedly, one of these rams was also heterozygous for a QTL that affects the overall carcass muscling (MyoMAX (TM)). This was accounted for by nesting MyoMAX (TM) status (carrier or non-carrier) within sire in the statistical analysis. Lambs were weighed and scanned by using X-ray computed tomography (CT) at an average age of 113 days. Ultrasound scan measurements, along with lamb weights, were taken at an average age of 140 days and lambs were then slaughtered. Carcasses were weighed and classified for fat cover and conformation scores, based on the Meat and Livestock Commission (MLC) carcass classification scheme, and then scanned by using a video image analysis (VIA) system. M. longissimus lumborum (MLL) width, as measured by CT scanning, was greater (P < 0.05) in lambs heterozygous for LM-QTL compared with non-carriers. MLL in LM-QTL carrier lambs was also significantly deeper, as measured by both ultrasound muscle depth at the third lumbar vertebrae (+3.7%; P < 0.05) and CT scanning at the fifth lumbar vertebrae (+3.4%; P < 0.01). Consequently, MLL area, was measured by using CT scanning, was significantly higher (+4.5%; P < 0.01) in lambs carrying a single copy of LM-QTL compared with non-carriers. Additional traits measured by CT, such as leg muscle dimensions, average muscle density and tissue proportions, were not significantly affected by LM-QTL. LM-QTL did not significantly affect total carcass lean or fat weights or MLC conformation and fat score classifications. Using previously derived algorithms, VIA could detect a significant effect of the LM-QTL on the predicted weight of saleable meat yield in the loin primal cut (+2.2%; P < 0.05), but not in the other primal cuts, or the total carcass.

This chapter discusses the inclusion of meat quality information in livestock breeding programmes which could provide permanent and cumulative genetic improvements in these traits with continued selection. Reasons why meat quality information is not more widely used in current breeding programmes are considered. Measurement techniques, genetic parameters and breeding programme designs that could be exploited to successfully incorporate meat quality traits are discussed, as well as suggestions of possible future directions for the inclusion of meat quality traits in livestock breeding programmes.

Failure to intubate and cross esophageal tumors by endosonography is reported in as many as 30% of cases and is thought to be associated with an especially poor prognosis. The aim of this study was to audit the above in a large consecutive case series of Endoscopic Ultrasound (EUS) examinations for esophageal cancer performed in a regional specialist cancer network with particular reference to outcome. A consecutive series of 411 patients underwent EUS examination by a specialist radiologist over a period of 9 years. Forty (10%) of patients required dilation, and there was total failure to cross the tumor in 12 patients (2.9%). Failure to traverse the primary tumor was associated with a diagnosis of squamous cell cancer (8 of 12 patients, 66%, rho = -0.182, P = 0.011). Limited staging information was obtained in 7 of these patients, which altered the computed tomography stage in 5 patients (71%, 3 upstaged, 2 downstaged). Six patients received definitive chemoradiotherapy, two patients surgery and four patients palliative chemotherapy. The median and 5-year survival in patients whose tumors were not crossed was 10 months and 28%, respectively, compared with 24 months and 24%, respectively in patients whose tumors were fully assessed. Failure to cross esophageal tumors in practice was far less common than the literature suggests, and esophageal tumor luminal stenosis should no longer be considered a limitation of endosonography.

This study investigated associations of prion protein (PrP) genotype with body composition and weight traits of Scottish Blackface ewes. Body composition was predicted using computer tomography (CT) scans to estimate muscle, carcass fat, internal fat, and bone weights. The traits were measured at 4 key seasonal production points (pre-mating, pregnancy, midlactation, and weaning) over 4 production cycles (2 to 5 yr old). There were 2,413 records for each of the CT traits measured on 335 ewes, and 26,649 records for each of the body condition score and BW traits for 2,356 ewes. From 1999 to 2004, animals were genotyped to determine polymorphisms at codons 136, 154, and 171, which are associated with scrapie susceptibility. Four alleles were found in the population (ARR, AHQ, ARQ, and VRQ). The data were analyzed using a linear mixed random regression model assuming that the direct additive genetic effect was a 2nd order Legendre polynomial function of time. The PrP genotype was included in the model as a fixed effect along with other fixed factors with significant effects (P0.05). Five separate analyses were carried out for each trait, depending on the method of classifying the PrP genotype. In the first analysis, animals were categorized according to the genotype. Only the 5 most common genotypes (ARR/ARR, ARR/AHQ, ARR/ARQ, AHQ/ARQ, and ARQ/ARQ) were included. In the last 4 analyses, animals were categorized according to the number of each PrP allele carried. For CT traits and body condition score, results showed that the PrP genotype has no association with the overall mean of the traits (averaged over age). For BW, ewes without the ARQ allele were at least 0.5 kg heavier than ARQ homozygous and heterozygous ewes. On the other hand, there was a significant interaction between PrP genotype and age of the ewe (i.e., the effect of PrP genotype was not the same at different ages for 5 out of the 6 traits studied). In general, ARQ carrying ewes mobilized more fat reserves at times of nutrient deficiency, such as during lactation, and gained it back more quickly by the mating season (when nutrients became abundant) than non-ARQ carriers. Therefore, selecting against this allele would have consequences on BW and seasonal mobilization of body reserves. The number of VRQ alleles (the most scrapie susceptible allele) carried was not significantly associated with any of the traits.

This study evaluates the effects of breed and sex, together with those of birth weight and litter size, on muscle fibre type characteristics in Texel (TEX) and Scottish Blackface sheep (SBF). The M.longissimus thoracis et lumborum (LTL) of TEX had a significantly higher total muscle cross-sectional area (16%), a higher total fibre number (20%) and a higher muscle CT density (5%) than the SBF but had a similar average muscle fibre size. The frequency of slow fibres in the LTL in TEX was lower than in SBF (7.5% vs. 9.6%). Muscle fibre histochemistry similarly demonstrated that the oxidative fibre frequency in TEX was 10% lower than in SBF. The inter-fibre lipid content in TEX was also significantly lower than in SBF. Correspondingly, TEX displayed higher frequency (91.7% vs. 90.9% in SBF) and higher relative total area (92.5% vs. 90.4% in SBF) of fast fibres. These breed differences in muscle fibre traits indicate underlying genetic variation, and future analyses will evaluate the link of these traits to meat quality and assess the usefulness of these traits in breeding programmes.

Live weight, subjective scores of condition and conformation, live animal video image analysis (LVIA), ultrasound and X-ray computed tomography (CT) scanning were used to investigate the best method or combination of methods for predicting carcass and meat quality traits in live Texel and Scottish Blackface lambs. Predictors derived from CT alone accounted for a high proportion of the variance in dissected fat and muscle weight in Texel lambs (adjusted R(2)=∼0.8), as well as intra-muscular fat content in the loin (∼0.6), but lower proportions in Blackface lambs (∼0.7 for fat, 0.4-0.5 for muscle and intra-muscular fat), after adjusting for sire and fixed effects. Adding traits measured by other in vivo methods increased prediction accuracies (adjusted R(2)) by up to 0.26, depending on trait and data set. Shear force and ultimate pH could not be accurately predicted using the traits considered here (adjusted R(2)0.4). Although the same methods tended to be best for predicting product quality traits between breeds, prediction accuracies differed.

Falipamil (2-[3-[3-(3,4-dimethoxyphenetylmethylamino]propyl]-5,6- dimethoxyphthalamidine; 1) is a new specific bradycardic agent for the treatment of sinus tachycardia. Pharmacokinetics of falipamil in humans (n = 6) was determined in plasma and urine after iv administration of 100 mg (1.85 MBq) per person of 14C-labeled drug by liquid scintillation counting and by a specific, sensitive reversed-phase totally automated HPLC system with fluorimetric detection. Recovery of total radioactivity was 91.8 +/- 3.7%, with 68.2 +/- 4.3% in urine and 23.6 +/- 2.5% in the feces. The majority of radioactivity was excreted within 24 to 48 h. The parent drug, falipamil (1), and its N-desmethyl-metabolite (2), which is approximately 100 times less active than 1, contributed 14.1 +/- 1.6 and 4.5 +/- 0.7%, respectively, of the dose to urinary excretion. Plasma protein binding of 1 and 2 was 87.9 +/- 1.2 (concentration range: 2000-8000 ng/mL) and 89.7 +/- 0.5% (concentration range: 62.5-1000 ng/mL), respectively. Plasma concentrations of 1 peaked at 2 min at 724 +/- 173 ng/mL, declined biphasically, and were fitted to a two-compartment open model. Plasma concentrations of 2 were very low, in all cases ranging from 0 to 35 ng/mL. The dominant terminal half-life (beta-phase) of 1 from plasma was 1.8 +/- 0.6 h (range 1.4-2.9 h), mean residence time was 2.4 +/- 0.4 h, total body clearance was 1108.5 +/- 119 mL/min, and renal clearance was 117 +/- 20 mL/min. All parameters demonstrated very low intersubject variability.

During investigation of DUP 996, a novel compound with potential memory-enhancing properties, nine parallel forms of the Buschke Selective Reminding Test were required. Nine word lists were created using a previously published methodology and word pool. In order to assess the equivalence of these word lists, data on each of the nine test forms were obtained from 21 subjects who received a single placebo dose in closely controlled clinical trial conditions. Analysis of variance revealed between-subject effect, confirming the large inter-individual differences in performance which had been observed during testing. The subjects were categorized as poor or good performers, and in a subsequent analysis the test forms were not found to differ significantly within the groups, confirming the utility of the methodology and word pool for the creation of unmatched word lists of similar difficulty.

This study compared the use of various models to describe growth in lambs of 2 contrasting breeds from birth to slaughter. Live BW records (n = 7559) from 240 Texel and 231 Scottish Blackface (SBF) lambs weighed at 2-wk intervals were modeled. Biologically relevant variables were estimated for each lamb from modified versions of the logistic, Gompertz, Richards, and exponential models, and from linear regression. In both breeds, all nonlinear models fitted the data well, with an average coefficient of determination (R2) of0.98. The linear model had a lower average R2 than any of the nonlinear models (0.94). The variables used to describe the best 3 models (logistic, Gompertz, and Richards) included estimated final BW (A); maximum ADG (B); age at maximum ADG (C); position of point of inflection in relation to A (D, for Richards only). The Richards and Gompertz models provided the best fit (average R2 = 0.986 to 0.989) in both breeds. Richards estimated an extra variable, allowing increased flexibility in describing individual growth patterns, but the Akaike's information criteria value (which weighs log-likelihood by number of parameters estimated) was similar to that of the Gompertz model. Variables A, B, C, and D were moderately to highly heritable in Texel lambs (h2 = 0.33 to 0.87), and genetic correlations between variables within-model ranged from -0.80 to 0.89, suggesting some flexibility to change the shape of the growth curve when selecting for different variables. In SBF lambs, only variables from the logistic and Gompertz models had moderate heritabilities (0.17 to 0.56), but with high genetic correlations between variables within each model (-0.88 or0.92). Selection on growth variables seems promising (in Texel more than SBF), but high genetic correlations between variables may restrict the possibilities to change the growth curve shape. A random regression model was also fitted to the data to allow predictions of growth rates at relevant time points. Heritabilities for growth rates differed markedly at various stages of growth and between the 2 breeds (Texel: 0.14 to 0.74; SBF: 0.07 to 0.34), with negative correlations between growth rate at 60 d of age and growth rate at finishing. Following these results, future studies should investigate genetic relationships between relevant growth curve variables and other important production traits, such as carcass composition and meat quality.

8 páginas, 4 tablas, 3 figuras., This study was implemented to evaluate the potential of visible and near infrared reflectance (NIR) spectroscopy to predict sensory characteristics related to the eating quality of lamb meat samples. A total of 232 muscle samples from Texel and Scottish Blackface lambs was analyzed by chemical procedures and scored by assessors in a taste panel (TP). Then, these parameters were predicted from Vis/NIR spectra. The prediction equations showed that the absorbance data could explain a significant but relatively low proportion of the variability (R-2 < 0.40) in the taste panel traits (texture, juiciness, flavour, abnormal flavour and overall liking) of the lamb meat samples. However, a top-tail approach, looking at the spectra of the 25 best and worst samples as judged by TP assessors, provided more meaningful results. This approach suggests that the assessors and the spectrophotometer were able to discriminate between the most extreme samples. This may have practical implications for sorting meat into a high quality class, which could be branded, into a, low quality class sold for a lower price for less demanding food use. Regarding the chemical parameters, both intramuscular fat and water could be more accurately predicted by Vis/NIR spectra (R-2 = 0.841 and 0.674, respectively) than sensory characteristics. In addition, the results obtained in the present study suggest that the more important regions of the spectra to estimate the sensory characteristics are related to the absorbance of these two chemical components in meat samples., The financial support of the Department for Environment, Food and Rural Affairs (Defra) and the Scottish Executive Environment and Rural Affairs Department (SEERAD) are gratefully acknowledged. S. Andre´s is grateful to the ‘‘Fundacio´n Alfonso Martı´n Escudero’’ (Spain) for financial assistance under a post-doctoral grant.

The reliability of a direct, contact, mechanical method for the quantification of body sway is assessed. Methodological aspects in measurement of the eyes open/eyes closed ratio are also considered.

1. This paper describes how birds move between horizontal perches at different heights with different angles separating them, using the time to complete the task and the number of birds failing to indicate ability. 2. For the first experiment, 4 groups of 15 birds (ISA Brown) were subjected to each of the experimental treatments (using three perches with angles of 0 degree (horizontal control), 30 degrees, 45 degrees or 60 degrees between them). The birds were required to move upward between the perches for each treatment and then to move downward between the perches, as a second part of the experiment. 3. Birds moving up between the perches took significantly longer at 60 degrees than at any other angle. No birds failed to complete the task. 4. For birds moving downward between the perches, the median time to complete the task increased significantly with angle. Furthermore, the number of birds failing to complete the task increased with angle. 5. A second experiment was conducted to test whether the vertical or horizontal component of distance affected birds' ability to negotiate perches separated by different angles. 6. For the second experiment 4 groups of 10 Lohmann Brown laying hens were subjected to each of the following treatments: two horizontal perches separated by 30 degrees or 60 degrees and either directly, horizontally or vertically separated by a set distance of 50 cm. Birds were required to move both up and down between perches. 7. Birds negotiated horizontally-separated perches more successfully at 30 degrees than at 60 degrees. However, when the vertical distance between the perches was 50 cm there was no significant difference in the ability of birds to move downward at 30 degrees or 60 degrees. For birds moving upward, 60 degrees was easier to negotiate than 30 degrees. 8. The vertical and horizontal separations, as well as the different angles affected the ability of birds to move between perches. There was a general decreasing trend in ability with increasing vertical separation between perches. 9. The findings are important in terms of arrangements of perches to improve bird welfare. To minimise the risk of injury, the angle between perches at different heights should be no more than 45 degrees, and the horizontal and vertical distances between these perches minimised, to allow the birds to be able to move downwards more easily.

Much of the past research into gender effects on lamb meat quality has focussed on comparing ram lambs with castrated males, but more recent comparisons between ram and ewe lambs have yielded variable results. The objective of the current research was to compare meat quality parameters of M. longissimus lumborum (LL), and M. semimembranosus (SM) from pasture-fed Texel ram (n = 94) and ewe (n = 114) lambs slaughtered at an average age of 144 days in a commercial abattoir. After aging carcasses for between 7 and 9 days, LL and SM were significantly tougher (higher shear values) for ram compared with ewe lambs (P < 0.001). LL from rams had significantly lower intramuscular fat percentage, and higher moisture content than LL from ewes. Differences in LL intramuscular fat percentage or ultimate pH did not explain the sex effect on LL shear force when tested individually or together as additional covariates in the model. Ram SM was lighter in colour (higher L*) and had a higher cooking loss than that of ewes (P < 0.001). The correlations between some of the traits within and between muscles clearly differed between the sexes. Finishing ram lambs to the specifications used in this experiment resulted in meat with relatively minor, but statistically significant differences in quality relative to that from ewe lambs.

1 page, 1 table.-- Contributed to: Proceedings of the British Society of Animal Science (Belfast, UK, 12-14 April, 2010)., [EN] Weight, proportion and distribution of fat and muscle in beef carcasses are of importance in order to maximise economic value and reduce waste. In-vivo ultrasound-measured predictors of cattle carcass composition could be of use when taken at the beginning of the finishing period (to allocate feeding groups and levels or for early selection of potential breeding stock), or pre-slaughter (to market-select finished animals, sort carcasses on quality, or feed back information from slaughter animals to breeding programmes). The aims of this study were to investigate the ability of ultrasound-measured fat and muscle depths to predict carcass composition and tissue distribution and to quantify the relative accuracy of predictions using ultrasound measurement taken at the start or end of the finishing period., SAC receives funding from the Scottish Government.