Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 4 de 4
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Meat Sci ; 148: 105-112, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30388474

RESUMO

Dietary supplementation of vitamin E (VitE) in a synthetic or natural form was examined. Forty-eight lambs were assigned (n = 16) to either a grain-based diet at moderate (MOD, 42 mg∙kg-1 VitE as all-rac α-tocopheryl acetate) or supranutritional (SUP, 285 mg∙kg-1 of vitE) levels of synthetic VitE or a lucerne hay-based diet (LUC; 37 mg∙kg-1 VitE) for 8 weeks. Meat from the LUC group had lower muscle n-6 and PUFA levels compared to meat from the MOD and SUP groups. Despite a similar VitE intake, muscle VitE was higher for LUC compared to MOD, while SUP lambs showed the highest VitE. Lipid oxidation did not differ between groups. For fresh meat, redness tended to be higher in LUC fed lambs than the other two groups, but brownness formation was only lower than the SUP group. For aged meat colour stability, redness tended to be higher in lambs fed SUP and LUC, whereas highest browning occurred in the MOD group.


Assuntos
Ração Animal/análise , Ácidos Graxos/análise , Carne Vermelha/análise , Carneiro Doméstico/fisiologia , Animais , Cor , Dieta/veterinária , Grão Comestível , Feminino , Masculino , Medicago sativa , Músculo Esquelético/química , Oxirredução , Vitamina E
2.
Anal Chim Acta ; 852: 137-45, 2014 Dec 10.
Artigo em Inglês | MEDLINE | ID: mdl-25441890

RESUMO

The presence of ß-boldenone II phase metabolites and prednisolone in urine samples, owing to endogenous or natural origin or illicit treatment, is under debate within the European Union. The detection of ß-boldenone conjugates, α-boldenone conjugates at concentrations higher than 2 ng mL(-1) and prednisolone above the cut-off level of 5 ng mL(-1) in urine have been, until now, critical in deciding if illegal drug use has occurred. The use of urine sometimes is not entirely satisfactory, especially when the drug is administrated at low doses or when its metabolic conversion is very fast. This subsequently would hamper its detection in urine. The introduction of a new, advantageous matrix where the illicit treatment can be investigated would be highly appreciated. In this study, we have developed and validated a simple and unique immunoaffinity clean-up procedure, which was applied to bovine bile samples, followed by two different analytical liquid chromatography-electrospray-tandem mass spectrometry methods. The first method tests androstadienedione, α- and ß-boldenone sulphate, glucuronate and related free forms, while the other method assays prednisolone, prednisone, dexamethasone, cortisone, and cortisol. The methods were validated according to European Commission Decision 2002/657/EC. The evaluated parameters were linearity, specificity, precision (repeatability and intra-laboratory reproducibility), recovery, decision limit and detection capability. The decision limits (CCα) were between 0.38 and 0.45 ng mL(-1) for anabolic steroids, and 0.13 and 0.15 ng mL(-1) as far as corticosteroids were concerned. Intra- and inter-day repeatability was below 15.8 and 19.9% for all analytes, respectively. The methods were applied to the analysis of some bile samples collected from untreated young bulls in order to investigate the presence of the studied steroids in this matrix.


Assuntos
Corticosteroides/análise , Androstadienos/análise , Bile/química , Bovinos , Espectrometria de Massas em Tandem/métodos , Testosterona/análogos & derivados , Animais , Bovinos/metabolismo , Cromatografia Líquida de Alta Pressão/métodos , Glucuronídeos/análise , Técnicas de Imunoadsorção , Limite de Detecção , Masculino , Testosterona/análise
3.
Food Addit Contam ; 21(8): 756-62, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15370825

RESUMO

European Directive 96/22/EC, which controls veterinary residues in animals, does not permit the presence of synthetic growth promoters in products of animal origin or in livestock. Boldenone is categorized in class A3 (growth promoters -- steroids) and is thus a banned substance. Testing of veal urine for banned substances is part of the European Union statutory programme for animals going into the food chain. In relation to this monitoring, three studies were conducted to investigate the apparent presence of the banned growth promoter boldenone in veal urine, which was suspected as being caused by interference from faecal contamination of the sample. In the first study, urine samples were collected at different times (time 0 and after 30 min) using (1) a conventional zoonotechnical apron and (2) a technique designed specifically to avoid faecal contamination ('kettle'). This resulted in samples that were, respectively, positive and negative for the presence of alpha-boldenone (alpha-BOL). In a second study, urine samples negative to alpha-BOL were collected from eight veal calves, but became positive after deliberate faecal contamination. In a third study, data obtained from the Italian RNP (Residual National Program) indicated that 18.1% of 3295 urine samples collected using the zootechnical apron were positive for alpha-BOL and 2.1% for beta-boldenone (beta-BOL), whilst of 902 samples collected using the kettle, beta-BOL was not detected in any samples and only 0.2% were positive to alpha-BOL, in concentrations lower than 2 ng ml(-1). These results further support the supposition that faecal contamination of the urine during sample collection can lead to false-positive results during boldenone analysis.


Assuntos
Carcinógenos/análise , Fezes/química , Contaminação de Alimentos/análise , Testosterona/análogos & derivados , Testosterona/análise , Animais , Bovinos , Reações Falso-Positivas , Hidrólise , Carne/análise , Testosterona/urina
4.
J Dairy Sci ; 80(9): 2137-42, 1997 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-9313156

RESUMO

Fifty-one lactating Italian river buffalo were used in an 84-d study to evaluate the effects of recombinant bovine somatotropin (bST) and Ca salts of long-chain fatty acids on productive performance. Treatments were 1) control diet, 2) the control diet plus 0.3 kg/d of added Ca salts of long-chain fatty acids, 3) the control diet plus 320 mg of recombinant bST injected every 21 d for four cycles, and 4) the control diet plus 0.3 kg/d of added Ca salts of long-chain fatty acids and 320 mg of recombinant bST administered as previously described. Administration of bST and Ca salts of long-chain fatty acids increased milk production. Milk fat percentage was not affected by treatments. The percentage of short-chain fatty acids in milk fat was reduced by the addition of Ca salts. Medium-chain, long-chain, and unsaturated fatty acids in milk fat were increased by bST treatment. Milk protein percentage was decreased by the addition of Ca salts of long-chain fatty acids. Milk casein content, as a percentage of total protein or as a percentage of true protein, was unaffected by bST. Body condition score was lowered by bST administration, but the addition of Ca salts of long-chain fatty acids reduced body condition loss in buffalo that were treated with somatotropin.


Assuntos
Búfalos/fisiologia , Cálcio , Ácidos Graxos/farmacologia , Hormônio do Crescimento/farmacologia , Leite/metabolismo , Animais , Bovinos , Ácidos Graxos/metabolismo , Feminino , Metabolismo dos Lipídeos , Proteínas do Leite/metabolismo , Proteínas Recombinantes/farmacologia , Sais
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...