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Nr Lambe - One of the best experts on this subject based on the ideXlab platform.
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prediction of intramuscular fat content and shear force in Texel lamb loins using combinations of different x ray computed tomography ct scanning techniques
Meat Science, 2018Co-Authors: N. Clelland, K.a. Mclean, Sara Knott, L Bunger, K R Matthews, Nr LambeAbstract:Abstract Computed tomography (CT) parameters, including spiral computed tomography scanning (SCTS) parameters, intramuscular fat (IMF) and mechanically measured shear force were derived from two previously published studies. Purebred Texel (n = 377) of both sexes, females (n = 206) and intact males (n = 171) were used to investigate the prediction of IMF and shear force in the loin. Two and three dimensional CT density information was available. Accuracies in the prediction of shear force and IMF ranged from R2 0.02 to R2 0.13 and R2 0.51 to R2 0.71 respectively, using combinations of SCTS and CT scan information. The prediction of mechanical shear force could not be achieved at an acceptable level of accuracy employing SCTS information. However, the prediction of IMF in the loin employing information from SCTS and additional information from standard CT scans was successful, providing evidence that the prediction of IMF and related meat eating quality (MEQ) traits for Texel lambs in vivo can be achieved.
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Prediction of intramuscular fat levels in Texel lamb loins using X-ray computed tomography scanning
Meat Science, 2014Co-Authors: N. Clelland, Lutz Bunger, Joanne Conington, K.a. Mclean, C. A. Maltin, Sara Knott, Nr LambeAbstract:For the consumer, tenderness, juiciness and flavour are often described as the most important factors for meat eating quality, all of which have a close association with intramuscular fat (IMF). X-ray computed tomography (CT) can measure fat, muscle and bone volumes and weights, in vivo in sheep and CT predictions of carcass composition have been used in UK sheep breeding programmes over the last few decades. This study aimed to determine the most accurate combination of CT variables to predict IMF percentage of M. longissimus lumborum in Texel lambs. As expected, predicted carcass fat alone accounted for a moderate amount of the variation (R(2)=0.51) in IMF. Prediction accuracies were significantly improved (Adj R(2)>0.65) using information on fat and muscle densities measured from three CT reference scans, showing that CT can provide an accurate prediction of IMF in the loin of purebred Texel sheep.
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the use of various live animal measurements to predict carcass and meat quality in two divergent lamb breeds
Meat Science, 2008Co-Authors: Nr Lambe, E A Navajas, C P Schofield, A V Fisher, G Simm, R Roehe, L BungerAbstract:Abstract 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 R2 = ∼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 R2) 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 R2
G S Lewis - One of the best experts on this subject based on the ideXlab platform.
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evaluation of columbia usmarc composite suffolk and Texel rams as terminal sires in an extensive rangeland production system i ewe productivity and crossbred lamb survival and preweaning growth
Journal of Animal Science, 2012Co-Authors: Timothy D Leeds, David R. Notter, Kreg A. Leymaster, Michelle R. Mousel, G S LewisAbstract:A 3-yr study was conducted to com- prehensively evaluate Columbia, Suffolk, USMARC- Composite (Composite), and Texel breeds as terminal sires in an extensive rangeland production system. The objective was to estimate breed-of-ram effects on ewe fertility, prolifi cacy, and dystocia, and sire breed effects on lamb survival and growth until weaning at approxi- mately 132 d of age. Data were from 22 Columbia, 22 Composite, 21 Suffolk, and 17 Texel rams with 957 exposures to 574 adult Rambouillet ewes (3- to 7-yr- old at lambing), 908 lambings, and 1,834 lambs. Ram breed did not affect ewe fertility (mean = 94.9%; P = 0.73), total number born per ewe lambing (mean = 2.02 lambs; P = 0.20), number born alive per ewe lamb- ing (mean = 1.90 lambs; P = 0.24), or number weaned per ewe lambing (mean = 1.45 lambs, P = 0.94). Dys- tocia rates were different (P = 0.01) for ewes mated to Columbia (12.2%), Composite (13.5%), Suffolk (25.7%), and Texel rams (31.9%) during 1 yr of the study, but differences among ram breeds were not repeatable (P ≥ 0.38) during the other 2 yr. Suffolk- sired lambs were heavier (P ≤ 0.02) at birth (5.5 kg) and weaning (40.3 kg) than lambs sired by the other breeds, which did not differ (P ≥ 0.34) for birth weight (mean = 5.3 kg). Texel-sired lambs (37.4 kg) were lighter (P ≤ 0.02) at weaning than Columbia- (38.8 kg) and Composite-sired (38.4 kg) lambs, which did not differ (P = 0.40) for weaning weight. Sire breed effect approached signifi cance (P = 0.06) for lamb survival to weaning; estimated survival probabilities were 0.87 (Columbia), 0.89 (Composite), 0.93 (Suf- folk), and 0.86 (Texel) for lambs reared by their birth dam. Interaction between sire breeds and birth weight affected (P < 0.001) lamb survival and revealed that lightweight Columbia- and Suffolk-sired lambs had a greater risk of death than lightweight lambs sired by Composite and Texel rams, but risk of death did not increase substantially for heavyweight lambs from any of the breeds. When mated to adult Rambouillet ewes in an extensive rangeland production system, the use of Suffolk rams is warranted to improve preweaning growth of market lambs and is not predicted to affect ewe fertility, ewe prolifi cacy, dystocia, or lamb surviv- al compared with the other sire breeds we tested.
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evaluation of columbia usmarc composite suffolk and Texel rams as terminal sires in an extensive rangeland production system iii prefabrication carcass traits and organ weights
Journal of Animal Science, 2012Co-Authors: Michelle R. Mousel, Timothy D Leeds, David R. Notter, H N Zerby, S J Moeller, G S LewisAbstract:: To evaluate terminal-sire breeds, harvest BW, prefabrication carcass measurements, and organ weights were evaluated over 3 yr for 518 crossbred wether lambs (ovis aries). Lambs were produced by single-sire matings of 22 Columbia, 22 USMARC-Composite (Composite), 21 Suffolk, and 17 Texel rams to adult Rambouillet ewes. Lambs were raised to weaning under an extensive western rangeland production system and finished in a feedlot on a high-energy finishing diet. Wethers were randomly assigned to be harvested at an average BW of 54.4, 61.2, or 68.0 kg and then transported to The Ohio State University abattoir for harvest. Wether BW was recorded before transport (off-test BW) and before harvest. Prefabrication carcass measurements and organ weights were recorded either after harvest or after an approximate 24-h chill. At comparable numbers of days on feed, Suffolk-sired lambs had heavier (P 0.06) from the other crossbred lambs. Texel- and suffolk-sired lambs had larger lm area and greater conformation scores than Columbia-sired lambs (P 0.18) and were intermediate for quality grades and leg scores. Sire breed did not affect (P > 0.05) shipping shrink, dressing percentage, pelt weight, liver weight, and fat depth. Adjusting data to a comparable off-test BW or CCW modified sire breed rankings for some measurements. Texel-sired lambs were equal or superior to lambs sired by other breeds for HCW, CCW, dressing percentage, pelt weight, LM area, quality grade, and leg and conformation scores. However, Texel-sired lambs also had values for kidney-pelvic fat weight, fat depth, and body wall thickness that were equal to or greater than those of lambs sired by the other breeds, indicating increased fatness at comparable BW. Producers can use these results to select terminal-sire sheep breeds that will complement their production system and improve market lamb value.
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evaluation of columbia usmarc composite suffolk and Texel rams as terminal sires in an extensive rangeland production system ii postweaning growth and ultrasonic measures of composition for lambs fed a high energy feedlot diet
Journal of Animal Science, 2012Co-Authors: David R. Notter, Timothy D Leeds, Michelle R. Mousel, J B Taylor, D P Kirschten, G S LewisAbstract:: Over 3 yr, postweaning growth patterns and changes in ultrasonic measurements of fat depth (FD) and LM area were assessed for 1,049 crossbred ewe and wether lambs (Ovis aries) produced by mating adult Rambouillet ewes to 1 of 22 Columbia, 22 USMARC-Composite (Composite), 21 Suffolk, or 17 Texel rams and raised to weaning under extensive Western rangeland conditions. After weaning, lambs were transitioned to a high-energy finishing diet in a feedlot, weighed weekly for 13 to 16 wk, and scanned using ultrasound at 2-wk intervals to estimate FD and LM area between the 12th and 13th ribs. Lambs sired by Suffolk rams were 5 to 12% heavier (P 0.20). Columbia-sired lambs had less FD (8.9 mm) but smaller LM areas (15.6 cm(2)) at 90 d on test (both P 0.10) to that of Texel-sired lambs (16.0 cm(2)) and superior (P < 0.01) to that of Composite- (15.7 cm(2)) and Columbia-sired lambs (15.4 cm(2)). Lambs sired by Suffolk rams were thus equal or superior to lambs sired by the other 3 breeds in growth, FD, and LM area at comparable ages, fatness at 60 kg, and LM area at a FD of 9.1 mm, but inferior in LM area to Texel- and Composite-sired lambs at comparable BW.
Menghua Li - One of the best experts on this subject based on the ideXlab platform.
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genome wide association analyses highlight the potential for different genetic mechanisms for litter size among sheep breeds
Frontiers in Genetics, 2018Co-Authors: S S Xu, Zhiqiang Shen, Emma Eyϸorsdottir, Jon Hallsteinn Hallsson, Tatyana Kiseleva, Juha Kantanen, Min Shen, Feng Wang, Menghua LiAbstract:Reproduction is an important trait in sheep breeding as well as in other livestock. However, despite its importance the genetic mechanisms of litter size in domestic sheep (Ovis aries) are still poorly understood. To explore genetic mechanisms underlying the variation in litter size, we conducted multiple independent genome-wide association studies in five sheep breeds of high prolificacy (Wadi, Hu, Icelandic, Finnsheep and Romanov) and one low prolificacy (Texel) using the Ovine Infinium HD BeadChip, respectively. We identified different sets of candidate genes associated with litter size in different breeds: BMPR1B, FBN1 and MMP2 in Wadi; GRIA2, SMAD1 and CTNNB1 in Hu; NCOA1 in Icelandic; INHBB, NF1, FLT1, PTGS2 and PLCB3 in Finnsheep; ESR2 in Romanov and ESR1, GHR, ETS1, MMP15, FLI1 and SPP1 in Texel. Further annotation of genes and bioinformatics analyses revealed that different biological pathways could be involved in the variation in litter size of females: hormone secretion (FSH and LH) in Wadi and Hu, placenta and embryonic lethality in Icelandic, folliculogenesis and LH signaling in Finnsheep, ovulation and preovulatory follicle maturation in Romanov, and estrogen and follicular growth in Texel. Taken together, our results provide new insights into the genetic mechanisms underlying the prolificacy trait in sheep and other mammals, suggesting targets for selection where the aim is to increase prolificacy in breeding projects. Key words: sheep, prolificacy, genome-wide association study, biological pathways, regulation
Barbara Good - One of the best experts on this subject based on the ideXlab platform.
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Breed differences in humoral and cellular responses of lambs to experimental infection with the gastrointestinal nematode Teladorsagia circumcincta
Veterinary Research, 2015Co-Authors: Albin Mostaque Ahmed, Assumpta Glynn, J.p. Hanrahan, Torres Sweeney, Simone Rocco Sebastiano, Orla Mary Keane, Anindya Mukhopadhya, Kevin Thornton, Barbara GoodAbstract:While Texel lambs have increased resistance to infection with the gastrointestinal nematode Teladorsagia circumcincta compared to Suffolk lambs, the underlying resistance mechanisms are still unknown. The aim of this study was to compare parasitological, humoral and cellular responses of Texel and Suffolk lambs over time following a single experimental infection with T. circumcincta. Gastrointestinal nematode free (but not naïve) lambs received a single oral dose of 3 × 104 infective T. circumcincta larvae. The variables examined included worm burden, mucosal and serum IgA, abomasal mast cells and eosinophils, haematological parameters and plasma pepsinogen. Texel lambs had significantly lower worm burden on day 14 and lower plasma pepsinogen concentration from day 14 onwards than Suffolks and their response in mucosal IgA to infection occurred earlier. The results from the study suggest that an earlier local IgA response in the Texel contributes to the resistant characteristics of the breed, while the increased level of plasma pepsinogen in the Suffolk lambs implies greater abomasal tissue damage arising from the nematode infection.
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major histocompatibility complex drb1 gene its role in nematode resistance in suffolk and Texel sheep breeds
Parasitology, 2005Co-Authors: G. Sayers, J.p. Hanrahan, Barbara Good, M. T. Ryan, J M Angles, Torres SweeneyAbstract:A potential control strategy for nematode infection in sheep is the implementation of a breeding programme to select for genes associated with resistance. The Texel breed is more resistant to gastrointestinal nematode infection than the Suffolk breed, based on faecal egg count, and this difference should enable the identification of some of the genes responsible for resistance. The objective of this study was to determine if variation at the ovine MHC-DRB1 locus was associated with variation in faecal egg count in Suffolk and Texel sheep. Ovar-DRB1 alleles and faecal egg count were determined for Texel (n = 105) and Suffolk (n = 71) lambs. Eight Ovar-DRB1 alleles, including 1 previously unknown allele, were identified in the Texel breed by sequence-base-typing. Seven Ovar-DRB1 alleles were identified in the Suffolk breed. Two Ovar-DRB1 alleles were common to both breeds, but were among the least frequent in the Suffolk population. In the Suffolk breed 1 Ovar-DRB1 allele was associated with a decrease in faecal egg count and 2 alleles with an increase in faecal egg count. This locus accounted for 14% of the natural variation in faecal egg count in Suffolks. There was no evidence for an association between Ovar-DRB1 alleles and faecal egg count in the Texel breed and the Ovar-DRB1 locus accounted for only 3% of the phenotypic variation in faecal egg count. These results suggest that the Ovar-DRB1 gene plays an important role in resistance to nematode infection in the Suffolk breed. The difference in faecal egg counts between these breeds may be attributable in part to the different allele profile at the Ovar-DRB1 locus.
Tatyana Kiseleva - One of the best experts on this subject based on the ideXlab platform.
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genome wide association analyses highlight the potential for different genetic mechanisms for litter size among sheep breeds
Frontiers in Genetics, 2018Co-Authors: S S Xu, Zhiqiang Shen, Emma Eyϸorsdottir, Jon Hallsteinn Hallsson, Tatyana Kiseleva, Juha Kantanen, Min Shen, Feng Wang, Menghua LiAbstract:Reproduction is an important trait in sheep breeding as well as in other livestock. However, despite its importance the genetic mechanisms of litter size in domestic sheep (Ovis aries) are still poorly understood. To explore genetic mechanisms underlying the variation in litter size, we conducted multiple independent genome-wide association studies in five sheep breeds of high prolificacy (Wadi, Hu, Icelandic, Finnsheep and Romanov) and one low prolificacy (Texel) using the Ovine Infinium HD BeadChip, respectively. We identified different sets of candidate genes associated with litter size in different breeds: BMPR1B, FBN1 and MMP2 in Wadi; GRIA2, SMAD1 and CTNNB1 in Hu; NCOA1 in Icelandic; INHBB, NF1, FLT1, PTGS2 and PLCB3 in Finnsheep; ESR2 in Romanov and ESR1, GHR, ETS1, MMP15, FLI1 and SPP1 in Texel. Further annotation of genes and bioinformatics analyses revealed that different biological pathways could be involved in the variation in litter size of females: hormone secretion (FSH and LH) in Wadi and Hu, placenta and embryonic lethality in Icelandic, folliculogenesis and LH signaling in Finnsheep, ovulation and preovulatory follicle maturation in Romanov, and estrogen and follicular growth in Texel. Taken together, our results provide new insights into the genetic mechanisms underlying the prolificacy trait in sheep and other mammals, suggesting targets for selection where the aim is to increase prolificacy in breeding projects. Key words: sheep, prolificacy, genome-wide association study, biological pathways, regulation
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Table_4.XLSX
2018Co-Authors: Lei Gao, Zhiqiang Shen, Emma Eyϸorsdottir, Jon Hallsteinn Hallsson, Min Shen, Feng Wang, Xing-long Xie, Yan-ling Ren, Tatyana KiselevaAbstract:Reproduction is an important trait in sheep breeding as well as in other livestock. However, despite its importance the genetic mechanisms of litter size in domestic sheep (Ovis aries) are still poorly understood. To explore genetic mechanisms underlying the variation in litter size, we conducted multiple independent genome-wide association studies in five sheep breeds of high prolificacy (Wadi, Hu, Icelandic, Finnsheep, and Romanov) and one low prolificacy (Texel) using the Ovine Infinium HD BeadChip, respectively. We identified different sets of candidate genes associated with litter size in different breeds: BMPR1B, FBN1, and MMP2 in Wadi; GRIA2, SMAD1, and CTNNB1 in Hu; NCOA1 in Icelandic; INHBB, NF1, FLT1, PTGS2, and PLCB3 in Finnsheep; ESR2 in Romanov and ESR1, GHR, ETS1, MMP15, FLI1, and SPP1 in Texel. Further annotation of genes and bioinformatics analyses revealed that different biological pathways could be involved in the variation in litter size of females: hormone secretion (FSH and LH) in Wadi and Hu, placenta and embryonic lethality in Icelandic, folliculogenesis and LH signaling in Finnsheep, ovulation and preovulatory follicle maturation in Romanov, and estrogen and follicular growth in Texel. Taken together, our results provide new insights into the genetic mechanisms underlying the prolificacy trait in sheep and other mammals, suggesting targets for selection where the aim is to increase prolificacy in breeding projects.
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Image_2.JPEG
2018Co-Authors: Lei Gao, Zhiqiang Shen, Emma Eyϸorsdottir, Jon Hallsteinn Hallsson, Min Shen, Feng Wang, Xing-long Xie, Yan-ling Ren, Tatyana KiselevaAbstract:Reproduction is an important trait in sheep breeding as well as in other livestock. However, despite its importance the genetic mechanisms of litter size in domestic sheep (Ovis aries) are still poorly understood. To explore genetic mechanisms underlying the variation in litter size, we conducted multiple independent genome-wide association studies in five sheep breeds of high prolificacy (Wadi, Hu, Icelandic, Finnsheep, and Romanov) and one low prolificacy (Texel) using the Ovine Infinium HD BeadChip, respectively. We identified different sets of candidate genes associated with litter size in different breeds: BMPR1B, FBN1, and MMP2 in Wadi; GRIA2, SMAD1, and CTNNB1 in Hu; NCOA1 in Icelandic; INHBB, NF1, FLT1, PTGS2, and PLCB3 in Finnsheep; ESR2 in Romanov and ESR1, GHR, ETS1, MMP15, FLI1, and SPP1 in Texel. Further annotation of genes and bioinformatics analyses revealed that different biological pathways could be involved in the variation in litter size of females: hormone secretion (FSH and LH) in Wadi and Hu, placenta and embryonic lethality in Icelandic, folliculogenesis and LH signaling in Finnsheep, ovulation and preovulatory follicle maturation in Romanov, and estrogen and follicular growth in Texel. Taken together, our results provide new insights into the genetic mechanisms underlying the prolificacy trait in sheep and other mammals, suggesting targets for selection where the aim is to increase prolificacy in breeding projects.
