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1.
J Anim Sci ; 93(5): 2045-55, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-26020300

RESUMO

Although genetic tests for many economically important beef cattle traits are commercially available, additional information is needed to help the industry better understand how the results from these tests translate into phenotypic outcomes. This information has important implications for marker-assisted management. The objective of this research was to determine the relationship between molecular breeding values (MBV) characterizing yield grade and marbling and distributions of phenotypic outcomes for yield grade and quality grade. Using data collected from commercially-fed cattle, mixed-model regression equations were estimated for yield grade and quality grade outcomes for both the full sample of commercial cattle (n= 8,995) and a subsample of black-hided steers (n = 4,790). Significant yield grade (P < 0.01) and marbling (P < 0.01) MBV effects were found. However, the yield grade MBV held up better at predicting phenotypic outcomes than the marbling MBV. Estimated conditional probability mass functions of yield and quality grade outcomes for the general population and black-hided steers were similar. Since distributions for black-hided steers were expected to be more applicable from a management perspective, we focused our analysis on these animals. For example, black-hided steers with "low" genetic potential for yield grade and marbling had about a 29% chance of achieving the base price or better on a price grid (yield grade 3 or lower and quality grade Low Choice or better). Increasing genetic potential for marbling increased the likelihood of achieving this same outcome. However, increasing genetic potential for yield grade was unlikely to increase overall carcass quality given its large deleterious effect on quality grade outcomes. Instead, simultaneous improvements in genetic potential for yield grade and marbling offered much more reliable improvements in overall carcass quality. For example, an animal with "moderate" genetic potential for both yield grade and marbling had a 46% chance of achieving the base price or better on a price grid, and an animal with the maximum observed MBV for these traits had a 66% chance of achieving this same outcome. Although the yield grade MBV held up better at predicting phenotypic outcomes, shifts in the distributions of yield grade and quality grade suggested that these increases were largely determined by the marbling MBV.


Assuntos
Cruzamento/métodos , Bovinos/crescimento & desenvolvimento , Bovinos/genética , Carne/normas , Fenótipo , Animais , Análise de Regressão , Especificidade da Espécie
2.
J Anim Sci ; 92(7): 3142-8, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24802037

RESUMO

This study was designed to explore consumers' perceptions about and knowledge of USDA beef quality grades. Data were collected from over 1,000 consumers in online surveys in November and December 2013, and estimates were weighted to force the sample to mirror the U.S. population in terms of age, gender, education, and region of residence. When asked to rank Prime, Choice, and Select grades in terms of leanness, only 14.4% provided the correct ranking with 57.1% of respondents incorrectly indicating steaks grading Prime were the leanest. Despite perceptions that the Prime name indicated the leanest product, in a subsequent question, 55.6% of respondents thought Prime grade to be the juiciest of the 3 grades. In addition to inquiring about perceptions of the grade names, respondents also indicated perceptions of pictures of steaks. Only 14.5% of respondents correctly matched the steak pictures with their corresponding USDA quality grade name, an outcome that is statistically worse than would have occurred through pure random matching (P = 0.03). When asked to match pictures of steaks with expected prices, 54.8% of respondents incorrectly matched the picture of the Prime steak with the lowest price level. More highly educated consumers with greater preferences for steak consumption were more likely to provide correct answers. Results reveal substantial confusion over quality grading nomenclature and suggest the need for more education or for a transition toward more descriptive terminology at the retail level.


Assuntos
Comportamento do Consumidor , Qualidade dos Alimentos , Carne/normas , United States Department of Agriculture/normas , Adolescente , Adulto , Fatores Etários , Idoso , Animais , Bovinos , Comportamento do Consumidor/estatística & dados numéricos , Escolaridade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estados Unidos , Adulto Jovem
3.
J Anim Sci ; 89(5): 1260-9, 2011 May.
Artigo em Inglês | MEDLINE | ID: mdl-21278104

RESUMO

Although several previous studies have identified associations between cattle carcass characteristics and various SNP, comparatively little work has sought to validate the marker panels currently sold and marketed by commercial genotyping companies. Panels typically use a handful of SNP, but these range from as few as 2 to more than 100. Data from 764 commercially fed steers and heifers were used to assess the relationships of growth and carcass traits and Igenity panel scores for ADG, marbling (or percentage of USDA Choice), rib-eye area (REA), tenderness, fat thickness, and USDA Yield grade (YG). Results revealed statistically significant, but low, correlations between carcass measurements and corresponding Igenity panel scores. Genetic correlations were computed among the various Igenity panels and demonstrated either that several common markers existed across the panels or that markers across panels were in high linkage disequilibrium. Across all breeds, the genotypic correlations between the Igenity panel scores for ADG, REA, marbling, and YG with observed ADG, REA, USDA Quality grade, and YG at slaughter were 0.51, 0.38, 0.63, and 0.59 (P < 0.01), respectively. The partial effects of the Igenity marbling panel persisted in a multivariate regression model. Net return was significantly affected only by marbling panel score; a 1-unit increase in marbling panel score increased the net return by an estimated $7.53 per animal.


Assuntos
Composição Corporal/fisiologia , Bovinos/fisiologia , Carne/normas , Animais , Composição Corporal/genética , Bovinos/genética , Feminino , Marcadores Genéticos , Masculino , Análise Multivariada , Polimorfismo de Nucleotídeo Único , Análise de Regressão
4.
B-ENT ; 7 Suppl 17: 27-32, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22338372

RESUMO

OBJECTIVE: The aim of this study was to analyse the results of minimally invasive endoscopic unilateral transsphenoidal surgery for pituitary adenomas. METHODS: A series of 83 patients presenting with a pituitary lesion was reviewed retrospectively. Surgical procedures were performed between February 2007 and December 2010. The extent of resection was evaluated on post-operative contrast-enhanced MRI. We also reviewed our complications and compared them with the literature. RESULTS: Our series included 10 micro- and 73 macro-adenomas, with cavernous sinus invasion in 60.3%. Fifty-three per cent were non-secreting. Complete resection of the macro-adenomas was achieved in 22.5% of the cases. Complications were as follows: 2 deaths (2.5%), 2 sinusitis (2.5%), 5 CSF leaks (6.2%), 1 meningitis (1.2%), 16 post-operative anterior lobe insufficiency (19.8%) and 4 persistent diabetes insipidus (4.9%). Thirty-seven patients (44.6%) presented with a compression of optical pathways with an improvement of visual acuity in 94.3%. CONCLUSIONS: Purely endoscopic unilateral endonasal transsphenoidal adenoma resection is minimally invasive surgery leading to a good rate of gross total tumour resection and it is associated with a low complication rate.


Assuntos
Adenoma/cirurgia , Endoscopia , Neuroendoscopia/métodos , Neoplasias Hipofisárias/cirurgia , Endoscopia/métodos , Humanos , Imageamento por Ressonância Magnética , Estudos Retrospectivos
5.
Anim Genet ; 39(3): 284-6, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-18454806

RESUMO

Prior research indicates that a SNP at position 305 of exon 2 in the leptin gene affects milk production in dairy cows. Dairy cows with at least one copy of the T allele have been shown to have higher milk production than CC cows. If that effect carries over to beef breeds, it is reasonable to expect that CT and TT beef cows will wean heavier calves than CC beef cows. We tested this hypothesis for a herd of mixed breed cows using anova. Results indicated that both crossbred CT and TT beef cows wean significantly heavier beef calves than CC crossbred beef cows. A lack of observations generally hinders detection of significance in other breeds. However, two other comparisons were found to be significant. The results suggest further investigation into the link between leptin genotype and calf weaning weights. Aside from interest to animal scientists, these results have the potential to alter mating and replacement selection decisions by cow-calf producers, given the importance of weaning weights on profitability.


Assuntos
Peso Corporal/genética , Bovinos/genética , Leptina/genética , Polimorfismo de Nucleotídeo Único , Animais , Cruzamento , Feminino , Genótipo , Desmame
6.
Int J Food Microbiol ; 112(2): 162-70, 2006 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-16860421

RESUMO

This paper describes the volatile metabolite production of spoilage bacteria (Pantoea agglomerans and Rahnella aquatilis) and spoilage yeasts (Pichia fermentans and Cryptococcus laurentii), previously isolated from mixed lettuce, on a simulation medium of shredded mixed lettuce (mixed-lettuce agar) both under air conditions and modified atmosphere (MA)-conditions at 7 degrees C. These latter conditions simulated the equilibrium modified atmosphere packaging, which is used to extend the shelf-life of shredded mixed lettuce. Besides volatile metabolites, organic acid metabolites and consumption of sugars were measured. Microbiological growth on the mixed-lettuce agar resulted in metabolite production and consumption of sugars. Bacteria and yeasts produced a range of volatile organic compounds both under air conditions and MA-conditions: ethanol, ethyl acetate, 2-methyl-1-propanol, 2-methyl-1-butanol, 3-methyl-1-butanol, 2,3-butanedione, 3-methyl-1-pentanol, 1-butanol and 1-hexanol. Under MA-conditions, 2-methyl-1-butanol, 3-methyl-1-butanol and ethanol were the first compounds that were detected in the headspace as being produced by the inoculated micro-organisms. In the case of the yeast P. fermentans, production of these compounds was detected from a count of 5.0+/-0.1 log cfu/cm(2) with a fast increase when exceeding 6.0-6.5 log cfu/cm(2). Unlike P. fermentans, the yeast C. laurentii showed a slow metabolism under MA-conditions, compared to air conditions. In the case of the bacteria, production of 2-methyl-1-butanol and 3-methyl-1-butanol was detected starting from a count of 6.7+/-0.1 log cfu/cm(2) in the case of R. aquatilis and from a count of 7.1+/-0.4 log cfu/cm(2) in the case of P. agglomerans with a fast increase when exceeding 8 log cfu/cm(2). No production of ethanol by the bacteria under MA-conditions was detected in contradiction to air conditions. It could be concluded that, if these counts are reached on the cut surfaces of shredded mixed lettuce which are simulated by the mixed-lettuce agar, sensorial quality of shredded mixed lettuce could be influenced by the microbiological production of metabolites.


Assuntos
Bactérias/crescimento & desenvolvimento , Embalagem de Alimentos/métodos , Conservação de Alimentos/métodos , Lactuca/microbiologia , Leveduras/crescimento & desenvolvimento , Bactérias/metabolismo , Dióxido de Carbono/metabolismo , Cryptococcus/crescimento & desenvolvimento , Cryptococcus/metabolismo , Meios de Cultura , Microbiologia de Alimentos , Lactuca/normas , Oxigênio/metabolismo , Pantoea/crescimento & desenvolvimento , Pantoea/metabolismo , Pichia/crescimento & desenvolvimento , Pichia/metabolismo , Rahnella/crescimento & desenvolvimento , Rahnella/metabolismo , Paladar , Temperatura , Volatilização , Leveduras/metabolismo
7.
Prog Urol ; 11(3): 507-11, 2001 Jun.
Artigo em Francês | MEDLINE | ID: mdl-11512466

RESUMO

The authors report a case of a multilocular cystic nephroma in an unusual site, extensively invading the pelvis and causing atypical symptoms of acute lumbar pain. The authors discuss the confusing terminology, the unusual presentation of this cystic tumour and the difficulty of establishing a definitive diagnosis of its benign nature before the operation in the light of a brief review of the literature.


Assuntos
Neoplasias Renais/patologia , Tumor de Wilms/patologia , Feminino , Humanos , Doenças Renais Císticas/patologia , Pessoa de Meia-Idade
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