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1.
J Anim Sci ; 95(4): 1553-1564, 2017 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-28464115

RESUMO

The objective of this study was to assess the impact of cattle finishing diet and muscle type on meat quality. Consumer sensory response, proximate composition, Warner-Bratzler shear force (WBSF), fatty acid composition, and volatile compounds were assessed from the gluteus medius (GM) and triceps brachii (TB) muscles of cattle ( = 6 per diet) which were grain-finished (USUGrain) on conventional feedlot or 2 forage diets, a perennial legume, birdsfoot trefoil-finished (USUBFT; ), and grass-finished (USUGrass; ). Diet had an interacting effect with muscle for all sensory attributes ( ≤ 0.002), except aroma and flavor ( ≥ 0.078). In forage-finished beef, tenderness, fattiness, overall liking, and WBSF tenderness of GM was greater ( < 0.05) than TB, whereas for USUGrain, the tenderness, fattiness, overall liking, and WBSF tenderness of both muscles were similar ( > 0.05) but the juiciness of TB was more liked than USUGrain GM ( < 0.05). The juiciness of forage-finished beef did not differ ( > 0.05) between GM and TB. Lower ( < 0.05) intramuscular fat (IMF) percent was determined for USUGrass beef in comparison with USUGrain beef. The IMF percent of USUBFT beef was similar ( > 0.05) to both USUGrass and USUGrain beef. However, IMF percent was not impacted by muscle type ( = 0.092). The ratio of -6:-3 fatty acids was affected by muscle dependent on diet ( = 0.016). The ratio of -6:-3 fatty acids was affected by the interaction of muscle × diet ( = 0.016). Between forage diets (USUGrass and USUBFT), -6:-3 ratios were similar ( > 0.05) between GM and TB, whereas within USUGrain, the GM was greater ( < 0.05) than the TB. Cumulative MUFA was greater ( < 0.05) in USUGrain compared with both USUGrass and USUBFT, which were similar ( > 0.05). Strecker aldehydes, ketones, pyrazines, and methional were affected ( ≤ 0.036) by muscle and found to have a greater concentration in GM compared with TB. Overall, consumers determined that USUGrain GM and TB had similar ( > 0.05) quality ratings. However, within forage-finished beef, the GM was perceived more frequently ( < 0.05) to be of premium quality and the forage-finished TB was more frequently ( < 0.05) rated as having unsatisfactory quality. These findings were in agreement with ratings of tenderness and overall liking. Therefore, in the context of our consumer group grilled GM and TB steaks, grain-finished beef provided more uniform quality and eating experience compared with forage-finished beef.


Assuntos
Bovinos/fisiologia , Carne Vermelha/normas , Tecido Adiposo/metabolismo , Ração Animal , Animais , Composição Corporal , Comportamento do Consumidor , Dieta/veterinária , Fabaceae , Ácidos Graxos/análise , Feminino , Masculino , Músculo Esquelético/química , Poaceae , Carne Vermelha/análise , Paladar
2.
J Anim Sci ; 94(5): 2184-97, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27285714

RESUMO

Consumer liking, proximate composition, pH, Warner-Bratzler shear force, fatty acid composition, and volatile compounds were determined from the LM (longissimus thoracis) of cattle ( = 6 per diet) finished on conventional feedlot (USUGrain), legume, and grass forage diets. Forage diets included a condensed tannin-containing perennial legume, birdsfoot trefoil (; USUBFT), and a grass, meadow brome ( Rehmann; USUGrass). Moreover, representative retail forage (USDA Certified Organic Grass-fed [OrgGrass]) and conventional beef (USDA Choice, Grain-fed; ChGrain) were investigated ( = 6 per retail type). The ChGrain had the greatest ( < 0.05) intramuscular fat (IMF) percentage followed by USUGrain, the IMF percentage of which was greater ( < 0.05) than that of USUGrass and OrgGrass. The IMF content of USUBFT was similar ( > 0.05) to that of both USUGrain and USUGrass. Both grain-finished beef treatments were rated greater ( < 0.05) for flavor, tenderness, fattiness, juiciness, and overall liking compared with USUGrass and OrgGrass. Consumer liking of USUBFT beef tenderness, fattiness, and overall liking were comparable ( > 0.05) with that of USUGrain and ChGrain. Flavor liking was rated greatest ( < 0.05) for USUGrain and ChGrain, and that of USUBFT was intermediate ( > 0.05) to those of ChGrain, USUGrass, and OrgGrass. Cumulative SFA and MUFA concentrations were greatest ( < 0.05) in ChGrain and USUGrain, whereas USUGrass and OrgGrass had lower ( < 0.05) concentrations. Concentrations of cumulative SFA and MUFA in USUBFT were intermediate and similar ( > 0.05) to those of USUGrain and USUGrass. Each forage-finished beef treatment, USUGrass, OrgGrass, and USUBFT, had lower ( < 0.001) ratios of -6:-3 fatty acids. Hexanal was the most numerically abundant volatile compound. The concentration of hexanal increased with increasing concentrations of total PUFA. Among all the lipid degradation products (aldehydes, alcohols, furans, carboxylic acids, and ketones) measured in this study, there was an overall trend toward greater quantities in grain-finished products, lower quantities in USUGrass and OrgGrass, and intermediate quantities in USUBFT. This trend was in agreement with IMF content, fatty acid concentrations, and sensory attributes. These results suggest an opportunity for a birdsfoot trefoil finishing program, which results in beef comparable in sensory quality with grain-finished beef but with reduced -6 and SFA, similar to grass-finished beef.


Assuntos
Ração Animal/análise , Comportamento do Consumidor , Fabaceae , Carne Vermelha/normas , Fenômenos Fisiológicos da Nutrição Animal , Animais , Bovinos , Dieta/veterinária , Grão Comestível , Gorduras , Ácidos Graxos/química , Humanos , Masculino , Paladar
3.
J Anim Sci ; 94(2): 845-57, 2016 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27065155

RESUMO

It was hypothesized that a tannin-rich legume such as sainfoin attenuates the negative postingestive effects of ergot alkaloids in tall fescue. Thirty-two 4-mo-old lambs were individually penned and randomly assigned to a 2 × 2 factorial arrangement with 2 legume species, sainfoin (SAN; 2.9% condensed tannins) or cicer milkvetch (CIC; without tannins) and a mixed ration containing tall fescue seed (50:30:20 seed:beet pulp:alfalfa) with 2 levels of endophyte infection (endophyte-infected tall fescue seed [E+; 3,150 ug/L ergovaline] or endophyte-free tall fescue seed [E-]). For a 10-d baseline period, half of the lambs were fed SAN and half were fed CIC and all lambs had ad libitum amounts of E-. In an ensuing 10-d experimental period, the protocol was the same except half of the lambs fed SAN or CIC received E+ instead of E-. Subsequently, all lambs could choose between their respective legume and seed-containing ration and between E+ and E-. Finally, an in vitro radial diffusion assay was conducted to determine whether tannins isolated from SAN would bind to alkaloids isolated from E+. All groups consumed similar amounts of E- during baseline period ( > 0.10), but lambs ate more E- than E+ during the experimental period ( < 0.05) and lambs offered SAN ate more E+ than lambs offered CIC ( < 0.05). Groups fed E- during the baseline and experimental periods had similar rectal temperatures ( > 0.10), but lambs fed E+ had lower rectal temperatures per gram of feed ingested when supplemented with SAN than with CIC ( < 0.05). Lambs fed E+ had greater concentrations of hemoglobin and more red blood cells than lambs fed E- ( < 0.05), but plasmatic concentrations of cortisol and prolactin did not differ among treatments ( > 0.10). All lambs preferred their treatment ration over their treatment legume, but lambs in the SAN and E+ treatment ate more legume + ration than lambs in the CIC and E+ (CIC-E+; < 0.05) treatment. All lambs preferred E- over E+, but lambs in the CIC-E+ treatment ate the least amount of E+ ( < 0.05). Binding of isolated SAN tannins to protein was reduced by the E+ isolate ( < 0.05), suggesting a tannin-alkaloid complexation but only from tannins extracted from SAN fed early in the experimental period. In summary, SAN supplementation increased intake of and preference for E+ and reduced rectal temperatures relative to CIC supplementation. Our results suggest that these effects were mediated by the condensed tannins in SAN through alkaloid inactivation, an interaction that declined with plant maturity.


Assuntos
Ração Animal/análise , Endófitos , Comportamento Alimentar/efeitos dos fármacos , Festuca/microbiologia , Ovinos/fisiologia , Taninos/química , Alcaloides , Animais , Dieta/veterinária , Suplementos Nutricionais , Alcaloides de Claviceps , Ergotaminas , Medicago sativa , Prolactina , Taninos/efeitos adversos
4.
Rev. esp. investig. quir ; 19(2): 59-62, 2016. ilus, graf
Artigo em Espanhol | IBECS | ID: ibc-154320

RESUMO

Introducción: La arteria femoral(AF) representa una de las principales vías de acceso endovascular. Algunas de las complicaciones de este procedimiento están vinculadas a la punción incidental de la arteria femoral profunda(AFP), por lo que el conocimiento de su anatomía y su disposición es fundamental. El objetivo de esta comunicación es estudiar el origen de la AFP. Material y métodos: Para este fin, se utilizaron 40 regiones inguinales (n=40) de cadáveres fijados previamente en solución en base a formol. Se registró: distancia del origen de la AF al origen de la AFP(D1), topografía del origen de la AFP respecto a la AF (anterior, medial, lateral, posterior, postero-lateral) y angulación entre la AF y el origen de la AFP. Resultados: D1 presentó una media de 32,13 mm (rango 17 - 55 mm). Con respecto a la topografía del origen de la AFP: 19 fueron posteriores (48%), 18 postero-laterales (45%), 2 casos de origen lateral (5%) y 1 caso medial (2%) respectivamente. La angulación entre el origen de la AFP y la AF fue de media 14,77° (rango 10-20°). Conclusiones: De acuerdo a nuestros hallazgos existiría una distancia promedio de 3 cm de la AF proximal al origen de la AFP. En la mayoría de los casos la AFP se origina de la cara posterior de la AF y en un ángulo agudo, no mayor a 20°. Este conocimiento debe ser tenido en cuenta tanto para el cirujano vascular, radiólogo intervencionista y hemodinamista en vistas al abordaje endovascular de la AF


Introduction: The femoral artery (FA) represents one of the preferred accesses for endovascular procedures. Complications of this access are in part related to incidental puncture of the profunda femoris artery (PFA), which demands proper knowledge of the anatomy of the PFA. The objective of this paper is to study the origin of the PFA. Material and methods. 40 femoral triangles (n = 40) of formalin-fixed adult cadavers were studied. It was registered: distance between de origin of the FA and the PFA (D1), position of the origin of the PFA (anterior, medial, lateral, posterior, postero-lateral), angle between the FA and the origin of the PFA. Results. D1 had a median of 32,13 mm (range 17 - 55 mm). Regarding the origin of the PFA: 19 were posterior (48%), 18 were postero-lateral (45%), 2 were lateral (5%) and 1 was medial (2%). The angle between FA and PFA was median 14.77° (range 10-20°). Conclusions: According to our findings the FA is in average 3 cm long before the origin of the PFA. In the vast majority of cases the PFA originates from the posterior aspect of the FA in an acute angle, not bigger of 20°. This knowledge is crucial in order to avoid complications when performing a femoral access for both vascular surgeons and interventional radiologists


Assuntos
Humanos , Artéria Femoral/cirurgia , Procedimentos Endovasculares/métodos , Dissecação/métodos , Artéria Femoral/anatomia & histologia , Cadáver , Dispositivos de Acesso Vascular
5.
J Dairy Sci ; 98(11): 7982-92, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26364095

RESUMO

This experiment was conducted to determine effects of feeding birdsfoot trefoil hay-based diets in comparison with an alfalfa hay-based diet on N utilization efficiency, ruminal fermentation, and lactational performance by mid-lactation dairy cows. Nine multiparous lactating Holstein cows (131 ± 22.6 d in milk), 3 of which were rumen fistulated, were fed 3 experimental diets in a replicated 3 × 3 Latin square design with 3 periods of 14 d of adaptation and 7 d of data and sample collection. Within squares, cows were randomly assigned to diets as follows: alfalfa hay-based diet (AHT), alfalfa and birdsfoot trefoil hay-based diet (ABT), and birdsfoot trefoil hay-based diet (BT). Intakes of dry matter and crude protein were similar across treatments, whereas ABT and BT diets resulted in decreased fiber intake compared with AHT. Feeding BT tended to increase neutral detergent fiber digestibility compared with AHT and ABT. Milk yield tended to increase for cows consuming ABT or BT diets. Milk true protein concentration and yield were greater for cows consuming ABT relative to those fed AHT. Concentration of total volatile fatty acids tended to increase by cows fed BT compared with those fed AHT and ABT. Feeding birdsfoot trefoil hay in a total mixed ration resulted in a tendency to decrease acetate proportion, but it tended to increase propionate proportion, leading to a tendency to decrease acetate-to-propionate ratio. Whereas concentration of ammonia-N was similar across treatments, cows offered BT exhibited greater microbial protein yield relative to those fed AHT and ABT. Cows offered birdsfoot trefoil hay diets secreted more milk N than AHT, resulting in improved N utilization efficiency for milk N. The positive effects due to feeding birdsfoot trefoil hay were attributed to enhanced neutral detergent fiber digestion, and thus it could replace alfalfa hay in high-forage dairy diets while improving N utilization efficiencies and maintaining lactational performance compared with alfalfa hay.


Assuntos
Ração Animal/normas , Bovinos/fisiologia , Fibras na Dieta/metabolismo , Lactação , Nitrogênio/metabolismo , Amônia/metabolismo , Ração Animal/classificação , Animais , Indústria de Laticínios , Detergentes , Dieta/veterinária , Digestão , Ácidos Graxos Voláteis/metabolismo , Feminino , Fermentação , Concentração de Íons de Hidrogênio , Lotus , Medicago sativa , Leite/metabolismo , Proteínas do Leite/metabolismo , Rúmen/metabolismo
6.
Water Sci Technol ; 49(2): 153-9, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-14982176

RESUMO

This paper focuses on developing a reproducible method for reducing calcium carbonate scale formation on heated surfaces where scaling can cause serious problems. It is known that calcium carbonate precipitation is sensitive to impurity ions, such as iron and zinc, even at trace concentration levels. In this paper two sets of experiments are reported. The first experiments were undertaken to investigate the effect of zinc, copper and iron dosing on CaCO3 nucleation and precipitation. Results from the experiments showed that the most effective inhibitor of CaCO3 precipitation was zinc and the effect was linked to dose levels and temperature. Copper and iron had little effect on precipitation in the dose range investigated. The second trial was undertaken to translate the precipitation data to scale formation. These tests were undertaken at 70 degrees C. 5 mg x L(-1) zinc dose reduced the scale formation by 35%. The effect of iron on calcium carbonate scaling rate was not significant. The physical nature of the material on which the scale is formed also influences the scaling. The scaling experiment was also used to investigate the effect of different surface material (stainless steel, copper and aluminium) on CaCO3 scale formation. Copper surface scaled the most.


Assuntos
Carbonato de Cálcio/química , Abastecimento de Água , Precipitação Química , Cobre/química , Corrosão , Temperatura Alta , Ferro/química , Teste de Materiais , Solubilidade , Zinco/química
7.
J Exp Bot ; 52(361): 1673-82, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11479332

RESUMO

The relationship between apoplastic peroxidase (EC 1.11.1.7) activity and cessation of growth in maize (Zea mays L.) leaf blades was investigated by altering elongation zone length. Apoplastic peroxidase activity in the elongation and secondary cell wall deposition zones of elongating leaf blades of the maize inbred line B73 was used as a control and compared to leaves of the dwarf mutant D8-81127, a near-isogenic line of B73 unresponsive to gibberellins, and to leaves of B73 plants to which gibberellic acid (GA(3)) had been applied via root uptake. Elongation zone length was increased by treatment with GA(3) through an increase in cell number as well as increased final cell length. The shorter elongation zone of dwarf leaves occurred primarily through reduced final cell length. Although elongation zone length differed among dwarf, control, and GA(3)-treated leaf blades, in all three treatments a transient increase in apoplastic peroxidase activity preceded a reduction in the segmental elongation rate in leaves. A peroxidase isoenzyme with pI 7.0 occurred in the leaf elongation zone during growth deceleration in all three treatments, and its activity decreased as growth displaced tissue into the region of secondary cell wall deposition. Growth cessation for all treatments coincided with the first appearance of peroxidase isozymes with pIs of 5.6 and 5.7. Based on the activity of particular isozymes relative to growth and differentiation, the pI 7.0 isoenzyme is most likely to be involved in cessation of cell elongation, while isozymes with pIs 5.6 and 5.7 are likely to be active in lignification.


Assuntos
Giberelinas/metabolismo , Meristema/crescimento & desenvolvimento , Peroxidase/metabolismo , Reguladores de Crescimento de Plantas/metabolismo , Folhas de Planta/crescimento & desenvolvimento , Zea mays/crescimento & desenvolvimento , Transporte Biológico , Diferenciação Celular/fisiologia , Divisão Celular/efeitos dos fármacos , Divisão Celular/fisiologia , Parede Celular/efeitos dos fármacos , Parede Celular/enzimologia , Giberelinas/farmacologia , Ponto Isoelétrico , Isoenzimas/metabolismo , Lignina/biossíntese , Meristema/efeitos dos fármacos , Meristema/metabolismo , Modelos Biológicos , Epiderme Vegetal/efeitos dos fármacos , Epiderme Vegetal/crescimento & desenvolvimento , Epiderme Vegetal/metabolismo , Reguladores de Crescimento de Plantas/farmacologia , Folhas de Planta/efeitos dos fármacos , Folhas de Planta/enzimologia , Folhas de Planta/metabolismo , Zea mays/enzimologia , Zea mays/metabolismo
8.
Plant Physiol ; 99(3): 879-85, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16669015

RESUMO

Previous work suggested that cell wall peroxidase activity increased as cells were displaced through the elongation zone in leaf blades of tall fescue (Festuca arundinacea Schreb.). In this study, two genotypes that differ in length of the elongation zone were used to examine the relationship between peroxidase activity in apoplastic fluid of intact leaf blade segments and the spatial distribution of leaf growth. Apoplastic fluid was extracted by vacuum infiltration and centrifugation, and peroxidase activity was assayed spectrophotometrically. Isoelectric focusing was used to characterize the isoforms of apoplastic peroxidase within the region of elongation and in the region of secondary cell wall deposition, which is distal to the elongation zone. A striking correlation was found in each genotype between both the location and timing of increase in apoplastic peroxidase activity and the onset of growth deceleration. Only cationic isoforms of apoplastic peroxidase could be identified in the elongation zone, whereas additional anionic isoforms appeared in the region of secondary cell wall deposition. We conclude that cessation of elongation growth in tall fescue leaf blades is likely to be related to the secretion of cationic isoforms of peroxidase into the cell wall.

9.
Plant Physiol ; 99(3): 872-8, 1992 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16669014

RESUMO

Cessation of cell expansion has been associated with cell wall cross-linking reactions catalyzed by peroxidase. This study utilized two genotypes of tall fescue (Festuca arundinacea Schreb.) that differ in length of the leaf elongation zone to investigate the relationship between ionically bound peroxidase activity and the spatial distribution of leaf elongation. Peroxidase activity was also localized histochemically in transverse sections of the leaf blade using 3,3' -diaminobenzidine. Soluble or soluble plus ionically bound peroxidase activities were extracted from homogenized segments of the elongating leaf blade and assayed spectrophotometrically. Activity of the ionically bound fraction, expressed per milligram fresh weight or per microgram protein, increased as cells were displaced through the distal half of the elongation zone, corresponding to the region in which the elongation rate declined. In both genotypes, the initial increase in activity preceded the onset of growth deceleration by about 10 hours. In the basal region where elongation began, histochemical localization showed that peroxidase activity was found only in vascular tissues. As cells were displaced farther through the elongation zone, peroxidase activity appeared in walls of other longitudinally continuous tissues such as the epidermis and bundle sheaths. Increase in ionically bound peroxidase activity and changes in localization of peroxidase activity occurred at comparable developmental stages in the two genotypes. The results indicate that cessation of elongation followed an increase in cell wall peroxidase activity.

10.
Plant Physiol ; 89(2): 549-56, 1989 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-16666581

RESUMO

Leaf elongation rate (LER) in grasses is dependent on epidermal cell supply (number) and on rate and duration of epidermal cell elongation. Nitrogen (N) fertilization increases LER. Longitudinal sections from two genotypes of tall fescue (Festuca arundinacea Schreb.), which differ by 50% in LER, were used to quantify the effects of N on the components of epidermal cell elongation and on mesophyll cell division. Rate and duration of epidermal cell elongation were determined by using a relationship between cell length and displacement velocity derived from the continuity equation. Rate of epidermal cell elongation was exponential. Relative rates of epidermal cell elongation increased by 9% with high N, even though high N increased LER by 89%. Duration of cell elongation was approximately 20 h longer in the high- than in the low-LER genotype regardless of N treatment. The percentage of mesophyll cells in division was greater in the high- than in the low-LER genotype. This increased with high N in both genotypes, indicating that LER increased with cell supply. Division of mesophyll cells adjacent to abaxial epidermal cells continued after epidermal cell division stopped, until epidermal cells had elongated to a mean length of 40 micrometers in the high-LER and a mean length of 50 micrometers in the low-LER genotype. The cell cycle length for mesophyll cells was calculated to be 12 to 13 hours. Nitrogen increased mesophyll cell number more than epidermal cell number: in both genotypes, the final number of mesophyll cells adjacent to each abaxial epidermal cell was 10 with low N and 14 with high N. A spatial model is used to describe three cell development processes relevant to leaf growth. It illustrates the overlap of mesophyll cell division and epidermal cell elongation, and the transition from epidermal cell elongation to secondary cell wall deposition.

11.
Aust Vet J ; 61(7): 205-7, 1984 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-6497803

RESUMO

Four young horses grazing pastures near industrial plants developed illthrift, lameness and skeletal abnormalities characterised by periarticular enlargement of the long bones. The clinical signs and lesions were attributed to hypocuprosis induced by an excessive intake of zinc from pasture. High pasture intakes of iron may have further compounded the problem.


Assuntos
Doenças Ósseas/veterinária , Cobre/deficiência , Doenças dos Cavalos/etiologia , Zinco/intoxicação , Animais , Doenças Ósseas/etiologia , Cobre/análise , Exposição Ambiental , Feminino , Cavalos , Ferro/análise , Coxeadura Animal/etiologia , Chumbo/análise , Masculino , Ratos , Zinco/análise
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