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1.
Poult Sci ; 96(4): 817-828, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27587727

RESUMO

An experiment was conducted to characterize a gut health challenge model consisting of a diet containing rye, wheat, and feather meal and a mild mixed-species Eimeria challenge, and to evaluate the effect of carbohydrase and protease on growth performance and gut health of young broilers. The study included 4 treatments: negative control, carbohydrase alone, protease alone, and combination of carbohydrase and protease. Each test diet was fed to 18 battery pens of broilers with 8 male birds per pen from 0 to 22 d of age. Carbohydrase improved body weight, feed intake, and feed conversion ratio (FCR) on d 7, 14, and 21(P < 0.01). Protease increased body weight on d 7 and 21 and improved 0 to 7 d FCR (P < 0.05). More lymphocyte infiltration was observed in small intestine mucosa of negative control birds on d 8, carbohydrase supplementation lessened this. Both carbohydrase and protease reduced digesta viscosity on d 22 with the carbohydrase effect being the greater of the two, and the combination effect was not different from the carbohydrase effect alone (P < 0.01). Ileal Clostridium perfringens of 15-day-old broilers was decreased by carbohydrase, a further reduction was achieved by combining carbohydrase with protease (P = 0.01). Liver vitamin E concentration on d 15 (P < 0.01) and 22 (P = 0.02) was increased by carbohydrase, and the carbohydrase effect was greater in the presence of protease on d 22 (P = 0.04). Plasma α-1-acid glycoprotein level and liver Zn and Cu concentrations of broilers were reduced by carbohydrase on d 15 (P < 0.01). Broilers fed carbohydrase had higher levels of plasma zeaxanthin on d 22 and higher levels of plasma lutein on d 15 and 22 (P < 0.01). In summary, a rye wheat based diet containing feather meal when fed to broilers in addition to a mild Eimeria challenge induced subclinical enteritis characterized by digestion inefficiency, dysbacteriosis, inflammation, and gut barrier failure; carbohydrase and protease could be effective tools to improve growth performance and gut health of broilers suffering from this type of subclinical enteritis.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Galinhas/crescimento & desenvolvimento , Suplementos Nutricionais , Glicosídeo Hidrolases/metabolismo , Íleo/fisiologia , Peptídeo Hidrolases/metabolismo , Ração Animal/análise , Animais , Infecções Assintomáticas , Galinhas/metabolismo , Infecções por Clostridium/microbiologia , Infecções por Clostridium/prevenção & controle , Infecções por Clostridium/veterinária , Clostridium perfringens/fisiologia , Dieta/veterinária , Suplementos Nutricionais/análise , Digestão/efeitos dos fármacos , Enterite/microbiologia , Enterite/prevenção & controle , Enterite/veterinária , Plumas , Glicosídeo Hidrolases/administração & dosagem , Íleo/efeitos dos fármacos , Íleo/microbiologia , Masculino , Peptídeo Hidrolases/administração & dosagem , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/prevenção & controle , Secale , Triticum
2.
J Anim Sci ; 92(12): 5464-75, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25367510

RESUMO

The study was conducted to determine effects of dietary supplementation with a blend of antioxidants (ethoxyquin and propyl gallate) on carcass characteristics, meat quality, and fatty acid profile in finishing pigs fed a diet high in oxidants. A total of 100 crossbred barrows (10.9±1.4 kg BW, 36±2 d of age) were randomly allotted to 5 diet treatments (5 replicate pens per treatment, 4 pigs per pen). Treatments included: 1) HO: high oxidant diet containing 5% oxidized soy oil and 10% PUFA source which contributed 5.56% crude fat and 2.05% docosahexanoic acid (DHA) to the diet; 2) VE: the HO diet with 11 IU/kg of added vitamin E; 3) AOX: the HO diet with antioxidant blend (135 mg/kg); 4) VE+AOX: the HO diet with both vitamin E and antioxidant blend; and 5) SC: a standard corn-soy control diet with nonoxidized oil and no PUFA source. The trial lasted for 118 d; on d 83, the HO diet pigs were switched to the SC diet due to very poor health. From that point, the VE pigs displayed the poorest performance. On d 118, 2 pigs from each pen were harvested for sampling. Compared to pigs fed SC diet, the HO and VE pigs (P<0.05) showed lighter carcass weight, less back fat, less lean body mass, and smaller loin eye area. In addition, the VE pigs had decreased dressing percentage than the AOX and VE+AOX pigs (65.7 vs. 75.3 and 74.2%). Compared to the SC pigs, greater moisture percentage (74.7 vs. 77.4%) and less extractable lipid content (2.43 vs. 0.95%) were found in VE fed pigs (P<0.05). Drip loss of loin muscle in VE pigs was less than SC pigs (0.46 vs. 3.98%, P=0.02), which was associated with a trend for a greater 24-h muscle pH (5.74 vs. 5.54, P=0.07). The antioxidant blend addition in the high oxidant diet attenuated all of these effects to levels similar to SC (P>0.05), except a* value (redness) and belly firmness. Visible yellow coloration of backfat and lipofuscin in HO and VE pigs was observed at harvest at d 118. The high oxidant diet resulted in greater concentration of DHA in backfat (P<0.001); switching the diet on d 83 resulted in HO pigs having a similar fatty acid profile to SC at d 118 pigs. Vitamin E concentration in plasma and muscle was greater in HO and SC than VE, AOX, and VE+AOX on d 118. Feeding the high oxidant diet caused a series of changes in carcass characteristics and meat quality. Addition of antioxidant blend attenuated many of these, whereas the protective effects of supplemental vitamin E at 11 IU/kg were minimal during the finisher phase of the study.


Assuntos
Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Antioxidantes/farmacologia , Composição Corporal/efeitos dos fármacos , Suplementos Nutricionais/análise , Carne , Sus scrofa/crescimento & desenvolvimento , Animais , Dieta/veterinária , Ácidos Graxos/análise , Masculino , Oxidantes/administração & dosagem , Oxirredução , Óleo de Soja , Suínos , Substâncias Reativas com Ácido Tiobarbitúrico , Vitamina E/administração & dosagem , Vitamina E/farmacologia , Zea mays
3.
Poult Sci ; 89(10): 2147-56, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20852106

RESUMO

The objective of this research was to determine the efficacy of 2 types of adsorbents [hydrated sodium calcium aluminosilicates (HSCAS) vs. a combination of clay and yeast cell wall] in preventing aflatoxicosis in broilers. A total of 275 one-day-old birds were randomly divided into 11 treatments, with 5 replicate pens per treatment and 5 chicks per pen. The 11 treatments included 3 diets without any adsorbent containing either 0, 1, or 2 mg/kg of aflatoxin B1 (AFB1) plus 8 additional treatments employing 2 dietary levels of AFB1 (1 or 2 mg/kg), 2 different adsorbents [Solis (SO) and MTB-100 (MTB)], and 2 different levels of each absorbent (0.1 and 0.2%) in a 2×2×2 factorial arrangement. Solis is a mixture of different HSCAS and MTB is a combination of clay and yeast cell wall. Feed and water were provided ad libitum throughout the 21-d study period. Body weight gain and feed intake were depressed and relative liver weight was increased in chicks fed AFB1 compared with the positive control (P<0.05). Severe liver damage was observed in chicks fed 2 mg/kg of AFB1 with lesions consistent with aflatoxicosis, including fatty liver and vacuolar degeneration. Serum glucose, albumin, total protein, Ca, P, and alkaline phosphatase concentrations were reduced by AFB1 (P<0.05). The addition of either SO or MTB ameliorated the negative effects of 1 mg/kg of AFB1 on growth performance and liver damage (P<0.05). However, supplemental MTB failed to diminish the negative effects of 2 mg/kg of AFB1, whereas SO was more effective compared with MTB at 2 mg/kg of AFB1 (P<0.05). These data indicate that the HSCAS product effectively ameliorated the negative effect of AFB1 on growth performance and liver damage, whereas the yeast cell wall product was less effective especially at the higher AFB1 concentration.


Assuntos
Aflatoxinas/toxicidade , Silicatos de Alumínio/uso terapêutico , Parede Celular/química , Micotoxicose/prevenção & controle , Doenças das Aves Domésticas/prevenção & controle , Leveduras/citologia , Ração Animal , Fenômenos Fisiológicos da Nutrição Animal , Animais , Galinhas , Dieta/veterinária , Suplementos Nutricionais , Contaminação de Alimentos , Fígado/efeitos dos fármacos , Fígado/patologia , Doenças das Aves Domésticas/sangue
4.
Poult Sci ; 88(1): 118-31, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19096066

RESUMO

Leg problems and resulting mortality can exceed 1% per week in turkey toms starting at approximately 15 wk of age. Dietary supplementation of organic trace minerals (MIN) and 25-hydroxycholecalciferol (HyD) may improve performance, decrease incidence of leg abnormalities, and increase bone strength. Nicholas 85X700 toms were assigned to 4 treatments consisting of a factorial arrangement of 2 concentrations of MIN (0 and 0.1% of Mintrex P(Se), which adds 40, 40, 20, and 0.3 mg/kg of Zn, Mn, Cu, and Se, respectively) and 2 concentrations of HyD (0 and 92 microg/kg of HyD). Diets were formulated to be equal in nutrient content and fed ad libitum as 8 feed phases. Feed intake and BW were measured at 6, 12, 15, 17, and 20 wk of age. Valgus, varus, and shaky leg defects were determined at 12, 15, 17, and 20 wk of age. Tibia and femur biomechanical properties were evaluated by torsion and bending tests at 17 wk of age. There were no treatment effects on BW. Only MIN significantly improved feed conversion ratio through to 20 wk of age. Cumulative mortality at 3 wk of age was greater among the MIN birds, but it was lower by 20 wk (P = 0.085). The MIN decreased the incidence of varus defects at 17 wk of age; shaky leg at 12, 15, and 17 wk of age; and valgus defects at 15, 17, and 20 wk of age. There were no MIN x HyD interaction effects on individual gait problems. Maximum load and the bending stress required for tibias to break in a 4-point assay were increased with MIN supplementation, especially when HyD was also added. Maximum shear stress at failure of femoral bones in a torsion assay was increased by supplementation with both MIN and HyD together. Dietary supplementation of MIN and HyD may improve biomechanical properties of bones. Dietary MIN supplementation may improve feed conversion of turkeys, likely by decreasing leg problems.


Assuntos
Calcifediol/farmacologia , Membro Posterior/patologia , Coxeadura Animal/tratamento farmacológico , Oligoelementos/farmacologia , Perus/crescimento & desenvolvimento , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Fenômenos Biomecânicos , Desenvolvimento Ósseo/efeitos dos fármacos , Osso e Ossos/efeitos dos fármacos , Dieta , Suplementos Nutricionais , Masculino , Caminhada/fisiologia
5.
Poult Sci ; 86(5): 877-87, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17435021

RESUMO

Mintrex Zn, Mintrex Cu, and Mintrex Mn organic trace minerals contain 16% Zn, 15% Cu, and 13% Mn with 80, 78, and 76% 2-hydroxy-4-(methylthio)butanoic acid (HMTBA) by weight as the organic ligand, respectively. Our objective was to determine if HMTBA from Mintrex was fully available as a Met source. In experiment 1, thirty-six broilers (7 to 10 d old) were orally gavaged with methyl-(14)C-labeled HMTBA, either as free HMTBA (Alimet feed supplement) or Zn bis(-2-hydroxy-4-methylthiobutyrate) (Mintrex Zn). Radiolabel incorporation from either source into protein was measured as a marker of bioavailable Met activity. Results demonstrated that the HMTBA from Mintrex Zn was equally available as free HMTBA to support protein synthesis. In experiment 2, five hundred seventy-six 1-d-old broilers were allotted to 12 dietary treatments (TRT) for a 21-d growth assay. A TSAA-deficient diet containing 0.70% total TSAA (TRT 1) was supplemented with 0.05, 0.10, 0.15, and 0.20% free HMTBA (TRT 2 to 5) to establish the standard Met response curve. Treatment 6 was analogous to TRT 2 but had an additional 160 ppm Zn, 80 ppm Cu, and 160 ppm Mn as sulfates. Treatments 7 to 12 were identical to TRT 2 but supplemented with 40 or 160 ppm Zn from Mintrex Zn, 20 or 80 ppm Cu from Mintrex Cu, or 40 or 160 ppm Mn from Mintrex Mn, respectively. For TRT 1 through 6, growth performance increased due to increasing Met addition (P < 0.01) but not to increasing inorganic trace minerals. For Mintrex Zn, Cu, and Mn (TRT 7 to 12), there was a linear increase in cumulative gain:feed ratio (P < 0.04), and for Mintrex Zn and Mn, there was a linear increase in cumulative gain (P < 0.03) to increasing Mintrex addition. A 1-slope broken-line model was used to calculate bioavailable Met activity from Mintrex for comparison with actual intake values. Results indicated that HMTBA from Mintrex was fully available as a Met source.


Assuntos
Ração Animal , Galinhas/crescimento & desenvolvimento , Galinhas/metabolismo , Metionina/metabolismo , Oligoelementos/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Animais , Dieta/veterinária , Suplementos Nutricionais , Duodeno/química , Marcação por Isótopo , Jejuno/química , Fígado/química , Masculino , Músculo Esquelético/química , Pâncreas/química
6.
J Dairy Sci ; 89(9): 3508-21, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16899687

RESUMO

Anabolic availability of the hydroxyl methionine analog, 2-hydroxy-4-methylthiobutanoic acid (HMTBA), given as oral doses to lambs, was quantified both directly as appearance in the portal vein and as synthesis to Met by digestive tract tissues. Eight lambs, prepared with vascular catheters in the mesenteric and portal veins plus the aorta, received twice daily for 7 d either 0.46 g or 2 g of HMTBA. On d 7, [1-13C]HMTBA was supplied as 1 oral dose while [methyl-2H3]Met was infused into the jugular vein. Peak absorption as HMTBA occurred 70 to 90 min after the oral dose. All digestive tract tissues converted HMTBA to Met, equivalent to 24% of the Met provided by the diet for the larger HMTBA dose. Overall, total availability of HMBTA averaged 17.9% of the dose (range 10.6 to 27.9%), with 12.5% (range 7 to 22%) as absorbed HMBTA and the remainder as Met synthesized by digestive tract tissues. Release of 13CO2 into the portal vein accounted for another 23% of the dose. In all digestive tract tissues, the d-isomer was present in a smaller proportion than in the dose. In terms of whole-body kinetics, HMTBA loss from the plasma followed first-order kinetics, with a mean biological half-life of 76 min. Using this value, a simple model was devised to estimate HMTBA absorption based on peripheral plasma samples. When compared with direct measures of absorption, the model gave a slope of 0.81 (R2 = 0.68) and offers a practical means to test HMTBA availability to animals.


Assuntos
Trato Gastrointestinal/metabolismo , Metionina/análogos & derivados , Ovinos/metabolismo , Absorção , Administração Oral , Animais , Isótopos de Carbono/análise , Cateterismo/veterinária , Marcação por Isótopo , Masculino , Metionina/administração & dosagem , Metionina/sangue , Metionina/metabolismo , Metionina/farmacocinética , Modelos Teóricos , Distribuição Aleatória , Fatores de Tempo , Trítio/análise
7.
J Dairy Sci ; 89(3): 1062-71, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16507703

RESUMO

This study was undertaken to determine how, and where, 2-hydroxy-4-methylthiobutyrate (HMTBA) can augment Met metabolism in lambs. Four lambs (initial body weight of 50 kg, SE = 2, and 6 mo of age) prepared with catheters in the mesenteric, portal, hepatic, and jugular veins plus the aorta, were fed at 1.5x maintenance on a grass hay, barley, fish meal, molasses/pre-mix (5:3:1:1, as fed) diet, supplied as hourly meals. Lambs were infused for 10 h with [methyl-2H3]Met (0.11 mmol/h) in a jugular vein and p-aminohippurate into the mesenteric vein. From 1 h onwards, successive 3-h infusions of saline (control), 0.55 mg/min (3.67 micromol/min), and 4.44 mg/min (29.6 micromol/min) of HMTBA were also infused into the mesenteric vein. Plasma, sampled continuously, was collected every 20 min during the last 60 min of each infusion. All infused HMTBA was recovered at the portal vein with 25% extracted subsequently by the liver. Portal appearance of total Cys and Met was unaltered by HMTBA infusion, but net splanchnic appearance of Cys increased (0.04, 0.08, 0.23 mmol/h, SEM = 0.05), whereas Met decreased (0.14, -0.01, -0.21 mmol/h, SED = 0.05). Despite this, arterial Met increased (27.0, 30.7, 51.5 microM, SEM = 2.1) as did Met irreversible loss rate (27.6, 28.7, 40.1 micromol/h, SEM = 0.51), equivalent to 40% of the HMTBA reentering the plasma after conversion to Met. These data indicate that, in ruminants, HMTBA is probably converted to Met within peripheral tissues; that is, where the metabolic need for Met exists.


Assuntos
Fígado/metabolismo , Metionina/análogos & derivados , Ovinos/crescimento & desenvolvimento , Ovinos/metabolismo , Animais , Isótopos de Carbono , Cisteína/sangue , Veias Hepáticas , Marcação por Isótopo , Veias Jugulares , Fígado/irrigação sanguínea , Veias Mesentéricas , Metionina/administração & dosagem , Metionina/sangue , Metionina/metabolismo , Veia Porta , Sensibilidade e Especificidade , Ácido p-Aminoipúrico/administração & dosagem
8.
J Dairy Sci ; 89(3): 1072-80, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16507704

RESUMO

Absorption and metabolism of the Met hydroxy analog 2-hydroxy-4-methylthiobutyrate (HMTBA) was examined using stable isotopes. In the first trial, Dl[1-13C]HMTBA was infused for 6 h (7.4 micromol/min) into the abomasum, and [2H3]Met was infused into the mesenteric vein, of 4 lambs prepared with vascular catheters across the splanchnic bed. Daily, lambs were offered 35 g of a mixed forage-concentrate feed/kg. Recovery of HMTBA at the portal vein was 87%, and of this, 63% bypassed the liver. In contrast, hepatic extraction of Met equaled or exceeded net absorption. Only small quantities of Met synthesized from HMTBA were exported from either the digestive tract or liver, but there was substantial and significant input from posthepatic tissues. In a second experiment, 3 of the lambs were killed following 4-h infusions of DL[1-13C]HMTBA and [2H3]Met with enrichments monitored in 15 tissues. Only kidney showed [1-13C]Met enrichment higher than plasma, which suggests that it must be a primary source of plasma Met derived from HMTBA. Based on comparison of plasma and intracellular [1-13C]:[2H3]Met enrichments, all tissues synthesized Met from HMTBA but to significantly different extents. The lowest values were for muscle, skin, brain, and lung; intermediate conversions occurred in rumen, omasum, abomasum, duodenum, jejunum, ileum, and cecum; and the greatest synthesis, equivalent to 22 to 24% of Met entry into cells, was observed for liver and kidney. Therefore, although liver and kidney both converted HMTBA to Met, it was retained by the former and exported by the latter. Under these experimental conditions, synthesis of Met from HMTBA completely eliminated use of dietary Met.


Assuntos
Metionina/análogos & derivados , Metionina/biossíntese , Ovinos/metabolismo , Abomaso , Absorção , Animais , Isótopos de Carbono , Cateterismo/veterinária , Dieta , Marcação por Isótopo , Rim/metabolismo , Fígado/metabolismo , Veias Mesentéricas , Metionina/administração & dosagem , Metionina/sangue , Metionina/metabolismo , Metionina/farmacocinética , Especificidade de Órgãos , Veia Porta
9.
Poult Sci ; 84(9): 1397-405, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16206561

RESUMO

Poultry diets are typically supplemented with DL-2-hydroxy-4(methylthio) butanoic acid (HMTBA, or the hydroxy analog of methionine) or DL-methionine (DLM). Although HMTBA and DLM provide methionine activity, they are structurally distinct molecules with different physiological characteristics until they are converted to L-methionine. The relative rates of intestinal HMTBA vs. DLM absorption have been controversial, and it has been claimed that HMTBA is not fully absorbed. We measured the uptake of HMTBA and DLM in an in vitro everted intestinal slice model. Sections of intestinal slices (jejunum and ileum) were incubated with 0.1 to 50 mM HMTBA that was radiolabeled or DLM that was radiolabeled, and absorption was measured by scintillation counting. The HMTBA uptake was equal to or greater than DLM absorption in each tissue and at every time point with one exception. Furthermore, the rates of HMTBA absorption were always equal to or significantly greater than DLM uptake. In a separate in vivo experiment, absorption of HMTBA and L-methionine was monitored along the entire gastrointestinal (GI) tract. Broilers were fed commercial-type corn-soy diets supplemented with 0.21% HMTBA. Digesta was collected from crop, proventriculus, gizzard, duodenum, jejunum, ileum, large intestine, and cloaca and analyzed for the concentration of free HMTBA and free methionine in each compartment. These studies demonstrated that HMTBA is absorbed completely and along the entire GI tract, especially the upper GI tract. Furthermore, there was a higher concentration of free L-methionine than HMTBA in the digesta from every segment distal to the gizzard.


Assuntos
Galinhas/metabolismo , Absorção Intestinal , Metionina/análogos & derivados , Metionina/farmacocinética , Animais , Dieta , Íleo/anatomia & histologia , Íleo/metabolismo , Jejuno/anatomia & histologia , Jejuno/metabolismo , Cinética , Metionina/análise , Glycine max , Zea mays
10.
Poult Sci ; 84(4): 634-43, 2005 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-15844822

RESUMO

This report will review the history of antibiotic growth promoter (AGP) use in the animal industry, concerns about development of antimicrobial resistance, and response in the European Union and United States to these concerns. A brief description of the history of legislation regarding feed use of antimicrobials in Denmark and the experience of animal producers following the 1998 ban will serve to illustrate the consequences on animal performance and health of withdrawing the approval for this use. The biological basis for antibiotic effects on animal growth efficiency will consider effects on intestinal microbiota and effects on the host animal and will use the germ-free animal to illustrate effects of the conventional microflora. The probability that no single compound will replace all of the functions of antimicrobial growth promoters will be considered, and methods to consolidate and analyze the enlarging database will be discussed.


Assuntos
Ração Animal , Criação de Animais Domésticos/métodos , Antibacterianos/farmacologia , Ração Animal/efeitos adversos , Criação de Animais Domésticos/legislação & jurisprudência , Criação de Animais Domésticos/tendências , Animais , Antibacterianos/administração & dosagem , Antibacterianos/efeitos adversos , Bactérias/efeitos dos fármacos , Dinamarca , Farmacorresistência Bacteriana , Uso de Medicamentos/legislação & jurisprudência , Uso de Medicamentos/tendências , União Europeia , Estados Unidos
11.
Poult Sci ; 84(2): 283-93, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15742965

RESUMO

Seven hundred and twenty hatchling broilers were allotted to 12 treatment groups. Groups 1 and 2 were fasted for 48 h posthatch; groups 3 and 4 were fasted for 48 h followed by ad libitum access to a 1% glutamine (Gln) diet; groups 5 and 6 had ad libitum access to a common diet; groups 7 and 8 had access to a 1% Gln diet posthatch; groups 9 and 10 were fed regular Oasis hatchling supplement; and groups 11 and 12 were fed Oasis sprayed with 1% Gln for the first 48 h posthatch. The birds in treatment groups 2, 4, 6, 8, 10, 11, and 12 were vaccinated with Eimeria maxima posthatch, and all birds were orally challenged with high dose E. maxima on d 22. During the first 2 wk, birds in group 7 had the highest gain and feed efficiency among treatments (P < 0.01). Compared with birds in the nonGln groups, birds in the Gln group had higher gain, feed efficiency, and livability (P < 0.05). Among the Fast (groups 1 to 4), Feed (groups 5 to 8), and Oasis (groups 9 to 12) groups, birds in the Feed groups had the highest gain during d 0 to 21 (P < 0.01). During d 22 to 28, birds in the Fast groups had the lowest BW and livability (P < 0.01), and the nonvaccinated birds had lower gain and feed efficiency relative to vaccinated birds (P < 0.01). Birds in the Feed and Oasis groups had higher villus height (VH) of mid small intestine than Fast groups at d 2 and 7 (P < 0.05), and nonvaccinated birds had higher VH than vaccinated birds (P < 0.01) at d 7 after hatch. On d 14, there were differences in serum interferon-gamma (P < 0.05) levels among treatments. During d 22 to 28, vaccinated birds had lower lesion scores in the mid small intestine than nonvaccinated birds (P < 0.01), and birds in the Feed or Oasis groups had lower lesion scores compared with the Fast groups (P < 0.02). These results indicated the importance of immediate access to feed posthatch, the beneficial effects of feeding Oasis hatching supplement and Gln after hatch, as well as the necessity of the vaccination program against coccidiosis challenge.


Assuntos
Ração Animal , Galinhas/crescimento & desenvolvimento , Coccidiose/prevenção & controle , Glutamina/farmacologia , Doenças das Aves Domésticas/prevenção & controle , Vacinas Protozoárias/imunologia , Ração Animal/análise , Animais , Galinhas/imunologia , Coccidiose/patologia , Dieta/veterinária , Eimeria/imunologia , Feminino , Interferon gama/sangue , Interleucina-2/sangue , Enteropatias Parasitárias/patologia , Enteropatias Parasitárias/prevenção & controle , Intestinos/patologia , Masculino , Doenças das Aves Domésticas/patologia
12.
Artigo em Inglês | MEDLINE | ID: mdl-12381384

RESUMO

The calpain system is a family of calcium activated proteases that degrade myofibrillar protein. Male broiler chickens (Ross) were provided a standard starter diet top-dressed with Oasis((R)) nutritional supplement (fed; Novus International, St. Louis, MO, USA), or they were not provided any feed (starved) for the first 3 days posthatch. Subsequently, the standard starter diet was provided to all chickens between 3 and 7 days posthatch. RNA was extracted from the Pectoralis thoracicus, and skeletal muscle-specific n-calpain-1 (p94) calpain, mu-calpain, and m-calpain expression was evaluated using quantitative Northern analysis. Early posthatch starvation did not (P>0.05) affect calpain mRNA levels on each day examined. Similarly, there were no (P>0.05) changes in mu-calpain or m-calpain mRNA levels between 0 and 7 days posthatch in fed birds. However, p94 calpain mRNA levels were significantly (P<0.05) lower at 7 days posthatch compared to 0 or 2 days posthatch. Therefore, in the early posthatch chicken, it appears that the calpain system may not be affected by the presence of oral nutrition, and that there is an age-related downregulation of p94 calpain mRNA expression.


Assuntos
Calpaína/genética , RNA Mensageiro/análise , Inanição/genética , Fatores Etários , Animais , Animais Recém-Nascidos , Northern Blotting , Galinhas , Regulação para Baixo , Privação de Alimentos , Masculino , Músculo Esquelético/química , Músculo Esquelético/metabolismo
13.
Poult Sci ; 80(11): 1619-24, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11732679

RESUMO

The methionine source DL-2-hydroxy-4methylthio-butanoic acid (DL-HMB; Alimet feed supplement) is widely used in the poultry industry. The purpose of this study was to determine the capacity of the broiler liver to remove DL-HMB from the circulation. Cannulae were implanted in the carotid artery and hepatic and hepatic portal veins in anesthetized male broilers (3.33 +/- 0.13 kg BW). In Experiment 1, birds (n = 5) were infused with DL-HMB solutions (diluted in saline, pH 7.2 to 7.4) into the hepatic portal vein at rates ranging from 4.4 to 22 mg/min per kg BW, whereas in Experiment 2, birds (n = 6) were infused with DL-HMB at rates ranging from 2.2 to 4.4 mg/min per kg BW. Plasma samples from each vessel were obtained before and after each 10-min DL-HMB infusion period with a 10-min clearance period allowed between each DL-HMB infusion. Regression analysis revealed a highly significant correlation in the amount of DL-HMB entering the liver via afferent vessels (afferent DL-HMB) and DL-HMB removed by the liver (y = 0.86(x) - 173, r2 = 0.98). The slope of this regression indicates that 86% of DL-HMB entering in afferent blood (i.e. from both the hepatic artery and hepatic portal vein) was removed or that the liver apparently metabolized 86% of the DL-HMB that entered the liver. The results indicate that the broiler liver has the capacity to remove DL-HMB from the circulation far in excess of that needed to metabolize DL-HMB that would enter the liver following gastrointestinal absorption in birds fed a conventional poultry diet. In addition, present results implicate the liver as a major site of removal from circulation and further metabolism of DL-HMB in chickens.


Assuntos
Ração Animal , Galinhas/metabolismo , Fígado/metabolismo , Metionina/análogos & derivados , Metionina/farmacocinética , Animais , Pressão Sanguínea , Artérias Carótidas , Suplementos Nutricionais , Veias Hepáticas , Masculino , Metionina/sangue , Veia Porta , Análise de Regressão
14.
Comp Biochem Physiol B Biochem Mol Biol ; 130(2): 237-50, 2001 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-11544094

RESUMO

This study was conducted to investigate the hepatic extraction of plasma free amino acids in anesthetized Single Comb White Leghorn (SCWL) males (Gallus domesticus). SCWL males were anesthetized and implanted with cannulae in the carotid artery, hepatic vein, hepatic portal vein and the left hepatic duct. Free amino acids in plasma and bile were determined before, during and after 30-min infusions of Saline (control), DL-Methionine (DL-Met) or DL-2-hydroxy-4-methylthio-butanoic acid (DL-HMB) into the hepatic portal vein. Hepatic extraction rates (HER) of amino acids were calculated based on the concentration of amino acids in plasma multiplied by estimations of blood flow in the hepatic portal vein, hepatic artery and hepatic vein. For the non-essential amino acids, alanine had the highest HER (46%). The liver also removed more than 20% of hepatic inflow of tyrosine and asparagine with substantial extraction (14-18%) of serine, glycine and glutamine, also. In contrast, less than 5% of hepatic inflow of glutamate and cystine were removed by liver. For the essential amino acids, HER for methionine, histidine and phenylalanine were 30, 14 and 17%, respectively, with less than 5% for branched-chain amino acids, lysine, arginine and threonine. Biliary secretion of amino acids represented a small percentage (<0.2%) of total hepatic extraction turnover of the amino acids. Infusion of methionine sources, DL-Met and DL-HMB, had no effect on hepatic metabolism of amino acids other than methionine. The results demonstrated for the first time, the hepatic extraction of circulating free amino acids in avian species in vivo.


Assuntos
Aminoácidos/isolamento & purificação , Galinhas/metabolismo , Fígado/química , Metionina/análogos & derivados , Metionina/farmacologia , Aminoácidos/sangue , Aminoácidos/química , Aminoácidos de Cadeia Ramificada/isolamento & purificação , Aminoácidos Essenciais/isolamento & purificação , Anestesia Intravenosa , Animais , Barbitúricos , Bile/metabolismo , Bile/fisiologia , Velocidade do Fluxo Sanguíneo/efeitos dos fármacos , Pressão Sanguínea/efeitos dos fármacos , Artérias Carótidas/fisiologia , Jejum/sangue , Artéria Hepática/fisiologia , Veias Hepáticas/fisiologia , Infusões Intravenosas/métodos , Fígado/irrigação sanguínea , Fígado/efeitos dos fármacos , Masculino , Metionina/administração & dosagem , Veia Porta/fisiologia , Fluxo Sanguíneo Regional
15.
J Anim Sci ; 78(4): 1078-83, 2000 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-10784201

RESUMO

Alimet (Novus Inter., Inc., St. Louis, MO) feed supplement (an 88% aqueous solution of 2-hydroxy-4-(methylthio) butanoic acid; HMB) is a source of L-Met commonly used in nonruminants and ruminants. The absorption of HMB across ovine omasal and ruminal epithelia was evaluated in this study. Ruminal and omasal epithelia were collected from eight lambs (BW = 67.6 kg +/- 9.1) and mounted in parabiotic chambers that were repeatedly sampled throughout a 60-min incubation. The appearance of HMB (using DL-[5-14C]-HMB as a radiolabeled marker) in serosal buffers increased quadratically (P < .004) with time in both tissues. More (P < .001) HMB appeared in the serosal buffers with omasal than with ruminal epithelia. Both tissues responded similarly, and, after 60 min of incubation, the accumulation of HMB within the tissues increased linearly (P < .001) as substrate concentration (.375, .75, 1.5, 3.0, 6.0, and 12.0 mM) increased in mucosal buffers. As the concentration of HMB in the mucosal buffers increased, there was a quadratic (P < .001) increase in the appearance of HMB in the serosal buffer of the omasal epithelium, indicating some saturation of the system. The increase in serosal appearance of HMB was linear (P < .001) with ruminal tissue. The results indicate that there are probably multiple mechanisms involved in the absorption of HMB. Because saturation was observed in the omasum, it is likely that mediated transport accounts for at least a portion of the absorption of HMB in the omasum. Other mechanisms (e.g., diffusion and(or) paracellular absorption) are responsible for the balance of the absorption. Omasal epithelium appears to have a greater capacity for HMB absorption than ruminal epithelium. The enzymes involved in the conversion of HMB to 2-keto-4-(methylthio)butanoic acid were found in ruminal and omasal epithelia, liver and kidney. These results indicate that HMB can be absorbed across ruminal and omasal epithelium and that HMB can be used as a source of L-methionine.


Assuntos
Absorção Intestinal/fisiologia , Mucosa Intestinal/metabolismo , Metionina/análogos & derivados , Omaso/metabolismo , Rúmen/metabolismo , Ovinos/fisiologia , Animais , Rim/metabolismo , Fígado/metabolismo , Metionina/farmacocinética
16.
Artigo em Inglês | MEDLINE | ID: mdl-10665366

RESUMO

Villus growth, enterocyte migration and proliferation were measured in the small intestine of poults (Meleagridis gallopavo) to determine if hen age and/or egg size influences these characteristics during the first week after hatching. At hatching, distal jejunal villi were 22.8 microns longer in poults from the older (48 weeks) versus the younger (34 weeks) hens (P < 0.05). Similarly, labeled enterocytes in distal jejunal sections from poults from the older hens had migrated 28 microns (10%) farther along the crypt-villus axis at hatching, as compared to poults from the younger hens (P < 0.05). Villus growth differences and enterocyte migration were not consistently affected by hen age or egg weight class in poults from 1 to 7 days old. These results suggest that even though intestinal villi may be more advanced developmentally at hatch in poults from the older hens, however post-hatch growth of the intestine or the poult is not affected by hen age or egg weight class.


Assuntos
Enterócitos/fisiologia , Intestino Delgado/citologia , Intestino Delgado/crescimento & desenvolvimento , Perus/embriologia , Perus/fisiologia , Animais , Bromodesoxiuridina/metabolismo , Bromodesoxiuridina/farmacocinética , Divisão Celular , Movimento Celular , Embrião não Mamífero/fisiologia , Feminino , Imuno-Histoquímica , Incubadoras , Intestino Delgado/ultraestrutura , Jejuno/citologia , Jejuno/crescimento & desenvolvimento , Jejuno/ultraestrutura , Idade Materna , Microvilosidades , Tamanho do Órgão , Óvulo/fisiologia , Antígeno Nuclear de Célula em Proliferação/análise , Antígeno Nuclear de Célula em Proliferação/imunologia , Antígeno Nuclear de Célula em Proliferação/metabolismo
17.
J Anim Sci ; 76(3): 781-7, 1998 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-9535338

RESUMO

We compared the effectiveness of 2-hydroxy-4-(methylthio) butanoic acid (HMB) and DL-methionine (DLM) as sources of L-methionine activity in methionine-deficient primary cultures of pig liver cells and methionine-deficient early-weaned pigs. Viable hepatocytes were obtained from minced pig liver and maintained in a high density, differentiated, nonproliferation cell culture system. Culture medium was supplemented with HMB, DLM, or L-methionine, and cells were pulse-dosed with L-[14C(U)]leucine for 24 h to determine the level of protein synthesis. Leucine incorporation per milligram of protein indicated a six-to eightfold increase in protein synthesis (P < .01) with methionine levels between 5 and 10 microM, regardless of source of methionine activity. Two 24-pen replicate methionine dose titrations were conducted with 95 early-weaned commercial crossbred pigs. The pelleted corn, dried whey, and porcine plasma basal diet contained 1.5% lysine, .23% methionine, and .48% cystine and was supplemented with 0, .05, or .10% methionine activity as DLM or HMB for 21 d. There was a 134, 104, and 61% increase (P < .01) in cumulative ADG for each successive week on study with a 30 and 19% improvement in feed/gain (P < .01) after 7 and 14 d. Performance responses due to source of methionine activity did not differ and slope ratio potency determinations (gain vs intake of methionine source) of HMB vs DLM indicated a 119, 111, and 95% relative activity for cumulative weekly performance. These results support the hypothesis that HMB and DLM provide equimolar levels of methionine activity in swine.


Assuntos
Ração Animal , Fígado/metabolismo , Metionina/análogos & derivados , Metionina/farmacologia , Animais , Células Cultivadas , Alimentos Fortificados , Leucina/metabolismo , Fígado/efeitos dos fármacos , Metionina/administração & dosagem , Metionina/deficiência , Proteínas do Leite , Biossíntese de Proteínas , Suínos , Desmame , Proteínas do Soro do Leite , Zea mays
18.
Br Poult Sci ; 39(5): 639-47, 1998 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9925317

RESUMO

1. The effects of varying the dietary arginine:lysine (Arg:Lys) ratio for broiler chickens at thermoneutral and high temperatures was studied in a series of 5 experiments which measured intestinal epithelial transport or evaluated growth and food efficiency with practical diets or diets supplemented with L-arginine free base. 2. The growth studies showed that increasing the Arg:Lys ratio at high temperatures produced consistent improvements in food conversion without any loss in growth. 3. Increasing dietary sodium chloride concentration reduced the Arg:Lys ratio necessary for optimum food conversion. 4. Food conversion responses were improved whether L-arginine free base was used as a dietary supplement in place of an inert filler or practical diets with differing ingredients were used to vary the Arg:Lys ratio. 5. In the presence of an equimolar concentration of lysine the uptake of arginine by the intestinal epithelium of heat-stressed broilers was reduced significantly compared with that of broilers at thermoneutral temperatures. 6. The results indicate that the ideal amino acid balance for broilers varies with ambient temperature.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Galinhas/fisiologia , Proteínas Alimentares/administração & dosagem , Transtornos de Estresse por Calor/veterinária , Mucosa Intestinal/metabolismo , Doenças das Aves Domésticas/fisiopatologia , Cloreto de Sódio na Dieta/administração & dosagem , Animais , Arginina/administração & dosagem , Arginina/metabolismo , Proteínas Alimentares/metabolismo , Transtornos de Estresse por Calor/fisiopatologia , Técnicas In Vitro , Lisina/administração & dosagem , Lisina/metabolismo , Masculino , Distribuição Aleatória
19.
Poult Sci ; 76(7): 961-7, 1997 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-9200231

RESUMO

Experiments were conducted to determine effects of Santoquin (ethoxyquin) and oxidized fat on liver and intestinal reduced (GSH) and oxidized (GSSG) glutathione, and pulmonary hypertension syndrome (PHS) mortality. Male broilers were randomly assigned in a 2 x 2 factorial consisting of 3.5% normal (NF) or oxidized (OxF) fat with or without ethoxyquin (E). Body weights and feed intake were monitored weekly, and tissues obtained at 3 and 7 wk for GSH and GSSG analysis. Compared to the NF group, NF/E gained more weight during the starter (0 to 3 wk), but not the grower (4 to 7 wk) period. Birds fed NF/E or NF exhibited greater feed efficiency in the starter period and greater gains during the starter and grower periods than birds fed OxF or OxF/E. No differences in PHS mortality between treatments were observed. Birds fed OxF exhibited lower liver GSSG at 3 wk than the other groups, but there were no differences in liver GSH. Duodenal GSH was higher in birds fed OxF/E than in birds of NF group at 3 and 7 wk. Ileal GSH was higher at 3 wk in OxF/E birds than in OxF birds, but no differences were observed at 7 wk. All tissues exhibited higher GSH levels at 7 wk than at 3 wk. Birds fed ethoxyquin, regardless of fat source, exhibited higher duodenal GSH at 3 and 7 wk and higher ileal GSH at 3 wk than birds that did not receive ethoxyquin. Higher GSH would be beneficial by enhancing protection of intestinal cells to deleterious effects of toxins or other forms of oxidative stress.


Assuntos
Antioxidantes/farmacologia , Galinhas/metabolismo , Gorduras na Dieta/farmacologia , Etoxiquina/farmacologia , Glutationa/análise , Intestinos/química , Fígado/química , Animais , Galinhas/fisiologia , Dieta/veterinária , Gorduras na Dieta/metabolismo , Ingestão de Alimentos/fisiologia , Glutationa/metabolismo , Hematócrito , Hipertensão Pulmonar/epidemiologia , Hipertensão Pulmonar/fisiopatologia , Hipertensão Pulmonar/veterinária , Incidência , Mucosa Intestinal/metabolismo , Intestinos/efeitos dos fármacos , Peróxidos Lipídicos/sangue , Fígado/efeitos dos fármacos , Fígado/metabolismo , Masculino , Oxirredução , Estresse Oxidativo/fisiologia , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/mortalidade , Doenças das Aves Domésticas/fisiopatologia , Distribuição Aleatória , Síndrome , Aumento de Peso/fisiologia
20.
Poult Sci ; 73(5): 627-39, 1994 May.
Artigo em Inglês | MEDLINE | ID: mdl-8047505

RESUMO

The objective of these experiments was to study the effect of intermittent high temperature (IHT) on performance of broilers fed different sources of methionine activity. Two 20-d experiments were conducted in which individually caged 28-d-old cockerels were exposed to a 5-d period of constant high temperature (HT, 30 to 32 C) followed by an equal period of thermoneutral (TN) temperatures (22 C) with the 10-d temperature cycle repeated twice. Birds held at 22 C were TN controls. Grower diets contained 3,275 kcal/kg ME and 20% CP and were supplemented with either 2-hydroxy-4-(methylthio)butanoic acid (HMB, Alimet Feed Supplement) or DL-Met up to a maximum of .88 to .90% total sulfur amino acids (TSAA). In Experiment 1, gain:feed but not average daily gain was greater (P < .05) for HMB than DL-Met birds subjected to IHT (.451 vs .413, respectively), but no treatment differences were observed for TN birds. Results of Experiment 2 demonstrated a linear response to HMB and DL-Met dose in TN (P < .01); however, only HMB-supplemented birds responded similarly in IHT (P < .01). These results are consistent with lower availability of DL-Met as a result of IHT. In vitro experiments indicated that capacity for uptake of DL-Met into intestinal epithelial cells was reduced in heat-stressed birds. Uptake of D-Met was more severely affected than was L-Met. Consequently, a third performance experiment compared the ability of D-Met and L-Met to support growth under conditions of HT. The results indicated that the effect of HT on broiler performance was mediated through reduced utilization of D-Met.


Assuntos
Galinhas/fisiologia , Temperatura Alta/efeitos adversos , Metionina/administração & dosagem , Animais , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Alimentos Fortificados , Masculino , Aumento de Peso/efeitos dos fármacos
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