The ability to accurately measure body or carcass composition is important for performance testing, grading and finally selection or payment of meat-producing animals. Advances especially in ...non-invasive techniques are mainly based on the development of electronic and computer-driven methods in order to provide objective phenotypic data. The preference for a specific technique depends on the target animal species or carcass, combined with technical and practical aspects such as accuracy, reliability, cost, portability, speed, ease of use, safety and for in vivo measurements the need for fixation or sedation. The techniques rely on specific device-driven signals, which interact with tissues in the body or carcass at the atomic or molecular level, resulting in secondary or attenuated signals detected by the instruments and analyzed quantitatively. The electromagnetic signal produced by the instrument may originate from mechanical energy such as sound waves (ultrasound – US), ‘photon’ radiation (X-ray-computed tomography – CT, dual-energy X-ray absorptiometry – DXA) or radio frequency waves (magnetic resonance imaging – MRI). The signals detected by the corresponding instruments are processed to measure, for example, tissue depths, areas, volumes or distributions of fat, muscle (water, protein) and partly bone or bone mineral. Among the above techniques, CT is the most accurate one followed by MRI and DXA, whereas US can be used for all sizes of farm animal species even under field conditions. CT, MRI and US can provide volume data, whereas only DXA delivers immediate whole-body composition results without (2D) image manipulation. A combination of simple US and more expensive CT, MRI or DXA might be applied for farm animal selection programs in a stepwise approach.
Born in Millheim, Texas, to a family of German immigrants who moved to Texas in the wake of the 1848 revolution, William Andreas Trenckmann was a teacher, journalist, and publisher who successfully ...combined his German heritage with a new, distinctly Texan identity. His education was cultivated at the brand new Agricultural and Mechanical College of Texas, where he distinguished himself as the valedictorian of the first graduating class; he later served on the college’s board of directors and was even offered the presidency. From 1907 to 1909, he represented Austin County in the Texas legislature. Trenckmann’s lasting contribution to Texas history, however, was the creation of Das Wochenblatt, a German-language weekly newspaper that he edited and published for over forty years. Das Wochenblatt became a popular and respected source of information for German-speaking immigrants, their descendants, and the Texas communities where they lived and worked. Through the paper, Trenckmann advocated for civil liberties and free elections. He also vigorously opposed prohibition, the Ku Klux Klan, and later the rise of Adolf Hitler and National Socialism. When the United States entered World War I, many German-language publications were suspended or otherwise heavily censored, but Trenckmann’s newspaper was granted a rare exemption from the wartime government. From 1931 to 1933, Trenckmann serialized his memoirs, Erlebtes und Beobachtetes , or “experiences and observations.” In Preserving German Texan Identity , historians Walter L. Buenger and Walter D. Kamphoefner present a revised and annotated translation of those memoirs as a revealing window into the lives of German Texans in the late nineteenth and early twentieth centuries.  
Poor neonatal survival constrains productivity and good welfare. The heritability of survival in sheep is very low, suggesting that genetic progress will be slow. Previously we have shown that a ...difficult birth and low neonatal lamb vigor are important predictors of future survival. In this study we investigated the heritability of these traits, and their relationship to production traits, as an alternative indirect route to improve lamb survival. Neonatal lamb data from 11,092 animals were collected over 2 years from 290 commercial sheep flocks, using previously developed methods to rapidly assess three traits (birth assistance, lamb vigor, sucking ability) on farm. Heritabilities for neonatal traits were moderate: birth assistance (mean ± standard error; 0.26 ± 0.03), lamb vigor (0.40 ± 0.04) and sucking ability (0.32 ± 0.03). Genetic correlations between neonatal traits were moderate to high, and positive. Heritabilities for production traits were also moderate: 8-week weight (0.27 ± 0.06), 20-week weight (0.39 ± 0.07), ultrasound muscle depth (0.37 ± 0.06). Genetic and phenotypic correlations between the neonatal traits and production traits were not significantly different from zero. However, lambs that were scored as of poor vigor at birth were less likely to be recorded at 8 or 20 weeks, indicating that they may have died. The data demonstrate that the neonatal survival traits of birth assistance, lamb vigor and sucking assistance are moderately heritable when treated as a lamb trait, indicating that selection to target these lamb traits would successfully, and efficiently, improve survival without influencing productivity.
Days to harvest (DTH) is the number of days a lamb is fed before reaching a target level of fatness. Although economically relevant, this trait has not been thoroughly evaluated in sheep. Most lambs ...harvested in the United Kingdom are crossbreds sired by purebred terminal sires, with Charollais, Suffolk, and Texel most commonly used. Sires from these breeds were selected on an index designed to increase lean growth while constraining fat. The purpose of this research was to 1) evaluate the effects of index selection in terminal sires on DTH and 2) evaluate the feasibility of incorporating DTH into genetic evaluation programs. Charollais, Suffolk, and Texel sheep had participated in sire referencing schemes where genetic links among flocks were established by sharing rams. Rams with high or low index scores were chosen from these schemes and mated to crossbred ewes at 3 farms in the United Kingdom. Lambs were harvested at a target 11% subcutaneous fat. Records on DTH from 6,350 lambs were analyzed in 2 ways: 1) as time to harvest fitting a survival model and 2) as a normally distributed variable in a bivariate analysis with weight at harvest. The survival analysis was stratified by rearing type (single or twin). In both approaches, sires were fitted using a multivariate normal distribution with a relationship matrix. Regardless of model fitted, sire index did not affect DTH (P>0.10). However, Texel-sired lambs reached harvest faster (P<0.01) than either Charollais- or Suffolk-sired lambs although DTH in those 2 breed types did not differ (P>0.1). Ewe lambs reached harvest faster than wethers (P<0.01). Lambs from older ewes were harvested faster (P<0.001). The heritability of DTH was 0.21 from the survival model and 0.20 from the bivariate model. Rank correlation of sire EBV between methods was 0.9, suggesting strong agreement. The use of high or low index sires did not extend DTH in lambs harvested at a target fatness. Importantly, there is no antagonism between improving carcass merit and extending the grazing season. Furthermore, DTH is moderately heritable. If economically justified within a breeding program, it could be reduced through genetic selection.
Acute gastrointestinal infections with transient mucosal inflammation frequently precede the onset of functional GI disorders with altered visceral sensory function. We hypothesized that an acute ...inflammation of the mucosa is linked to long-lasting alterations of afferent visceral pathways. Utilizing abdominal wall electromyography, we tested the visceromotor response to tonic rectal distension (60 mm Hg/3 min) in fasted, conscious, male Lewis rats (n = 40) with a barostat device before and 2, 4, 15, and 17 weeks after rectal instillation of saline or trinitrobenzenesulfonic acid plus ethanol. Tissue samples from paired controls were obtained to assess histologic tissue alterations. Inflammatory changes were present up to 2 weeks after acid/ethanol instillation but not after saline instillation. Compared to baseline measurements, the visceromotor response to colorectal distension increased significantly and reached a maximum 17 weeks (P < 0.001) after induction of colitis, while it decreased in control experiments (P < 0.05). In conclusion, these data suggest that an acute inflammation has long-term effects on somatosensory functioning.
Accounting for environmental heteroscedasticity and genetics by environment interaction (G×E) in genetic evaluation is important because animals may not perform predictably across environments. The ...objectives of this study were to evaluate the presence and consequences of heteroscedasticity and G×E on genetic evaluation. The population considered was crossbred lambs sired by terminal sires and reared under commercial conditions in the UK. Data on 6325 lambs sired by Charollais, Suffolk and Texel rams were obtained. The experiment was conducted between 1999 and 2002 on three farms located in England, Scotland and Wales. There were 2322, 2137 and 1866 lambs in England, Scotland and Wales, respectively. A total of 89 sires were mated to 1984 ewes of two types (Welsh and Scottish Mules). Most rams were used for two breeding seasons with some rotated among farms to create genetic links. Lambs were reared on pasture and had their parentage, birth, 5 week, 10 week, and slaughter weights recorded. Lambs were slaughtered at a constant fatness, at which they were ultrasonically scanned for fat and muscle depth. Heteroscedasticity was evaluated in two ways. First, data were separated into three subsets by farm. Within-farm variance component estimates were then compared with those derived from the complete data (Model 1). Second, the combined data were fitted, but with a heterogeneous (by farm) environmental variance structure (Model 2). To investigate G×E, a model with a random farm by sire (F×S) interaction was used (Model 3). The ratio of the F×S variance to total variance was a measure of the level of G×E in the population. Heterogeneity in environmental variability across farm was identified for all traits (P<0.01). Rank correlations of sire estimated breeding value between farms differed for Model 1 for all traits. However, sires ranked similarly (rank correlation of 0.99) for weight traits with Model 2, but less so for ultrasonic measures. Including the F×S interaction (Model 3) improved model fit for all traits. However, the F×S term explained a small proportion of variation in weights (<2%) although more in ultrasonic traits (at least 10%). In conclusion, heteroscedasticity and G×E were not large for these data, and can be ignored in genetic evaluation of weight but, perhaps, not ultrasonic traits. Still, before incorporating heteroscedasticity and G×E into routine evaluations of even ultrasonic traits, their consequences on selection response in the breeding goal should be evaluated.
Artificial selection for improved productivity may reduce an animal's ability to cope with pathogens. Here, we used Roslin mice, uniquely divergently selected for high (ROH) and low (ROL) body ...weight, to assess interactive effects of differing growth potential and protein nutrition on host resilience and resistance. In a 2 x 2 x 6 factorial design, ROH and ROL mice were either sham-infected or infected with 250 L(3)Heligmosomoides bakeri and fed diets with 30, 80, 130, 180, 230 and 280 g crude protein per kg. The infected ROL-30 treatment resulted in clinical disease and was discontinued. In the remaining ROL mice, infection and feeding treatments did not affect growth but infection reduced weight gain in ROH-30, ROH-80 and ROH-130 mice. Although infection resulted in temporarily reduced food intake (anorexia) in both mouse lines, mean food intake over the whole experiment was reduced in ROH mice only. ROH mice excreted more worm eggs and had higher worm burdens, with relatively fewer female worms, than ROL mice. However, these resistance traits were not sensitive to dietary protein. These results support the view that selection for high growth may reduce the ability to cope with pathogens, and that improved protein nutrition may to some extent ameliorate this penalty.
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 8%, 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 × 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). This was accounted for by nesting MyoMAX 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.
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 (Bluefaced Leicester × 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 (+4.5%; 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 (+3.0%; 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 (+5.9%; 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.
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