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1.
Anim Biosci ; 2024 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-39210810

RESUMO

Objective: The current study aimed to investigate the effect of increasing ß-mannanase supplementation in diets containing copra meal (CM) on growth performance, meat quality, liver health, intestinal morphology, and nutrient utilization in broiler chickens. Methods: A total of 1,600 3-d-old Ross 308 broiler chickens (initial body weight [BW] ± SD = 43.3 ± 1.08 g) were randomly allotted to 1 of 5 treatment groups with 8 replicates. One group was fed a corn-soybean meal-based diet (control). Other 4 diets were prepared by inclusion of 10% commercial CM in the control diet with 0, 400, 800, and 1,600 U ß-mannanase/kg. Experiments lasted for 32 d. Results: Birds fed the control diet had less (p=0.001) feed conversion ratio (FCR) than those fed diets containing 10% CM without ß-mannanase supplementation. Increasing supplementation of ß-mannanase in diets containing 10% CM had no linear and quadratic effects on body weight gain, feed intake, and FCR in broiler chickens. The control diet had greater (p<0.01) apparent total tract retention (ATTR) of DM, GE, and N as compared to the diets containing 10% CM without ß-mannanase supplementation; however, no differences in the ATTR of Ca and P were identified between 2 diets. There were no linear and quadratic effects of increasing supplementation of ß-mannanase on the ATTR of DM, GE, N, Ca, and P in broiler diets containing 10% CM. Both inclusion of 10% CM and increasing supplementation of ß-mannanase in broiler diets did not affect apparent ME (AME) and N-corrected ME (AMEn) values in treatment diets. Conclusion: The use of 10% CM in broiler diets during growing and finishing period impairs growth performance by decreasing energy and nutrient utilization in diets. Increasing ß-mannanase supplementation in diets containing 10% CM has no positive effects on performance, meat quality, liver health, intestinal morphology, and nutrient utilization in broiler chickens.

2.
Poult Sci ; 102(12): 103101, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37826904

RESUMO

The current experiment aimed to investigate the effect of dietary glycine (Gly) supplementation on productive performance, egg quality, stress response, and fatty liver incidence in laying hens raised under heat stress (HS) conditions. A total of two hundred eighty 24-wk-old Lohmann Brown-Lite laying hens were randomly allotted to 1 of 4 dietary treatments with 7 replicates. The negative control (NC) diet was prepared to meet or exceed the nutrient and energy requirement for Lohmann Brown laying hens, whereas the positive control (PC) diet was formulated to increase AMEn by 100 kcal/kg compared with the NC diet. Two additional diets were prepared by supplementing 0.341% and 0.683% Gly to the NC diet. All hens were exposed to cyclic HS at 31.4 ± 1.17°C for 8 h/d and 26.7 ± 1.10°C for the remaining time for a 12-wk trial. Results indicated that increasing supplementation of Gly in diets tended (linear, P = 0.088) to decrease the FCR of laying hens. Increasing supplementation of Gly in diets increased (linear, P < 0.05) eggshell lightness and decreased (linear, P < 0.05) egg yolk color. Moreover, a tendency for a quadratic association (P < 0.10) of serum aspartate aminotransferase and alanine aminotransferase concentrations with increasing supplementation of Gly was observed. Increasing supplementation of Gly in diets decreased (linear, P < 0.05) blood heterophil:lymphocyte ratio of laying hens. Hens fed the NC diet showed higher fatty liver incidence (P < 0.05) than those fed the PC diet, but increasing supplementation of Gly decreased (linear, P < 0.05) fatty liver incidence of laying hens. In conclusion, increasing supplementation of Gly up to 0.683% in diets decreases FCR, stress response, and fatty liver incidence in laying hens raised under HS conditions.


Assuntos
Suplementos Nutricionais , Fígado Gorduroso , Feminino , Animais , Glicina , Galinhas/fisiologia , Incidência , Ração Animal/análise , Óvulo , Dieta/veterinária , Fígado Gorduroso/prevenção & controle , Fígado Gorduroso/veterinária , Resposta ao Choque Térmico
3.
Anim Biosci ; 36(11): 1632-1646, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37654169

RESUMO

OBJECTIVE: The objective of the present study was to investigate the effect of dietary betaine (BT) supplementation on the hepatic transcriptome profiles in broiler chickens raised under heat stress (HS) conditions. METHODS: A total of 180 (21-d-old) Ross 308 male broiler chicks were allotted to 1 of 3 treatment groups with 6 replicated cages in a completely randomized design. One group was kept under thermoneutral conditions at all times and was fed a basal diet (PC). Other 2 groups were exposed to a cyclic heat stress condition. One of the 2 groups under heat stress conditions was fed the basal diet as a negative control (NC), whereas the other group was fed the basal diet supplemented with 0.2% BT. All chickens were provided with diets and water ad libitum for 21 d. Following the experiment, the liver samples were collected for RNA sequencing analysis. RESULTS: Broiler chickens in NC and BT group had decreased (p<0.05) growth performance. In the transcriptome analysis, the number of differentially expressed genes were identified in the liver by HS conditions and dietary BT supplementation. In the comparison between NC and PC treatments, genes related to energy and nucleic acid metabolism, amino acid metabolism, and immune system were altered by HS, which support the reason why heat-stressed poultry had decreased growth performance. In the comparison between NC and BT treatments, genes related to lipid metabolism, carbohydrate metabolism, and immune system were differently expressed under HS conditions. CONCLUSION: HS negatively impacts various physiological processes, including DNA replication, metabolism of amino acids, lipids, and carbohydrates, and cell cycle progression in broiler chickens. Dietary BT supplementation, however, offers potential counteractive effects by modulating liver function, facilitating gluconeogenesis, and enhancing immune systems. These findings provide a basis for understanding molecular responses by HS and the possible benefits of dietary BT supplementation in broiler chickens exposed to HS.

4.
Poult Sci ; 102(4): 102497, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36739800

RESUMO

The objective of the current experiment was to investigate the effect of dietary concentrations of ME and neutral detergent fiber (NDF) on productive performance, egg quality, fatty liver incidence, and hepatic fatty acid metabolism in aged laying hens. A total of three hundred twenty 75-wk-old Hy-Line Brown laying hens were allotted to 1 of 4 dietary treatments with 8 replicates. Each replicate consisted of 10 consecutive cages with 1 hen per cage. The experiment was conducted using a completely randomized design with 2 × 2 factorial arrangement consisting of 2 levels of ME (normal [commercially recommended AMEn levels; 2,730 kcal/kg] and low [50 kcal/kg reduction in AMEn; 2,680 kcal/kg]) and 2 levels of NDF (low [9.01 and 9.61%; normal-ME and low-ME diets, respectively] and high [12.57 and 13.42%; normal-ME and low-ME diets, respectively]) in the diet. The diets and water were provided to hens on an ad libitum basis for 12 wk. Results indicated that no interactions between dietary concentrations of ME and NDF were observed for all measurements except for egg yolk color, eggshell thickness, and 2 hepatic gene expressions (i.e., carnitine palmitoyl transferase 1A and malic enzyme). For the main effects, increasing NDF concentrations in diets increased (P < 0.05) feed intake without affecting other productive performance. Hens fed normal-ME and high-NDF diets showed the darkest (P < 0.05) egg yolk color among those fed treatment diets, showing an interaction (P < 0.05). Increasing NDF concentrations in low-ME diets did not influence eggshell thickness, but those in normal-ME diets increased eggshell thickness in laying hens, showing an interaction (P < 0.05). For the main effects, increasing concentrations of dietary NDF or ME reduced (P < 0.05) hepatic fat concentrations with decreasing expressions in several genes related to fatty acid synthesis. In conclusion, increasing NDF concentrations in commercially-recommended ME diets decrease hepatic fat concentrations in aged laying hens, and therefore, may have a preventative effect on the fatty liver development in aged laying hens.


Assuntos
Galinhas , Fígado Gorduroso , Feminino , Animais , Detergentes , Incidência , Óvulo , Dieta/veterinária , Fígado Gorduroso/veterinária , Ácidos Graxos , Ração Animal/análise , Suplementos Nutricionais
5.
J Anim Sci Biotechnol ; 13(1): 79, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35843965

RESUMO

BACKGROUND: Heat stress (HS) is one of the most important threats for the current poultry industry. Therefore, many efforts have been made to ameliorate the adverse effect of HS on poultry production; however, physiological and molecular mechanisms pertaining to HS are still limited in poultry. Therefore, the objective of the current study was to investigate functional alterations based on individual and integrated transcriptomes in the liver and jejunal mucosa tissues of broiler chickens exposed to HS conditions. RESULTS: Broiler chickens exposed to HS showed decreased growth performance and increased corticosterone concentrations in the feather. In the transcriptome analysis, the number of differentially expressed genes (DEGs) were identified in the liver and jejunal mucosa by HS conditions. In the liver, genes related to amino acid oxidation, tryptophan metabolism, lipid metabolism, oxidative phosphorylation, and immune responses were altered by HS, which support the reason why heat-stressed poultry had decreased productive performance. In the jejunal mucosa, genes related to defense systems, glutathione metabolism, detoxification of xenobiotics, and immune responses were differently expressed by HS conditions. The integrated transcriptome analysis with DEGs found in the liver and jejunal mucosa showed a considerable connectivity between the core nodes in the constructed networks, which includes glutathione metabolism, xenobiotic metabolism, carbon metabolism, and several amino acid metabolisms. CONCLUSIONS: The core network analysis may indicate that increased requirement of energy and amino acids in the jejunal mucosa of broiler chickens exposed to HS conditions is likely compromised by increased oxidation and synthesis of amino acids in the liver. Therefore, our results may provide comprehensive insights for molecular and metabolic alterations of broiler chickens raised under HS conditions, which can aid in the development of the novel strategies to ameliorate the negative effect of HS on poultry productivity and health.

6.
Anim Biosci ; 34(11): 1839-1848, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34445851

RESUMO

OBJECTIVE: The objective of the present study was to investigate the comparative effects of dietary functional nutrients including glutamine (Gln), chromium picolinate (Cr picolinate), vitamin C (Vit C), betaine (Bet), and taurine (Tau) on growth performance, meat quality, immune responses, and stress biomarkers in broiler chickens raised under heat stress conditions. METHODS: A total of 420 21-d-old Ross 308 male broiler chickens (initial body weight = 866±61.9 g) were randomly allotted to 1 of 7 treatment groups with 6 replicates. One group was kept under thermoneutral conditions and was fed a basal diet (PC, positive control). Other 6 groups were exposed to a cyclic heat stress condition. One of the 6 groups was fed the basal diet (NC, negative control), whereas 5 other groups were fed the basal diet supplemented with 0.5% Gln, 500 ppb Cr picolinate, 250 mg/kg Vit C, 0.2% Bet, or 1.0% Tau. The diets and water were provided ad libitum for 21 d. RESULTS: Broiler chickens in NC group had decreased (p<0.05) growth performance and immune responses measured based on cutaneous basophil hypersensitivity (CBH), but increased (p<0.05) stress responses measured based on feather corticosterone concentrations and blood heterophil:lymphocyte than those in PC group. However, none of dietary functional nutrients had a positive effect on growth performance of broiler chickens. Dietary supplementation of 250 mg/kg Vit C improved (p<0.05) CBH responses of broiler chickens, but other functional nutrients had no such an improvement in CBH responses. All functional nutrients decreased (p<0.05) stress responses of broiler chickens. CONCLUSION: Functional nutrients including Gln, Cr picolinate, Vit C, Bet, and Tau at the supplemental levels used in this study decrease stress responses of broiler chickens to a relatively similar extent. However, this reduction in stress responses could not fully ameliorate decreased productive performance of broiler chickens raised under the current heat stress conditions.

7.
J Phys Chem B ; 110(24): 11683-90, 2006 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-16800463

RESUMO

We have comparatively investigated the photophysics of a series of bis-metal doubly N-confused hexaphyrins(1.1.1.1.1.1) using time-resolved fluorescence, femtosecond transient absorption, two-photon absorption measurements, and geometry-optimized ab initio calculations. Bis-Zn(II) and free-base doubly N-confused hexaphyrins exhibit well-resolved and red-shifted B- and Q-like absorption bands compared with porphyrins. Their allowed transitions are (pi,pi) transitions of the hexaphyrin ring, as confirmed by the HOMO and LUMO frontier orbitals based on ab initio calculations at the B3LYP/6-31G level. On the other hand, the absorption spectra of bis-Cu(II) and bis-Co(II) doubly N-confused hexaphyrins are relatively broad, presumably due to large couplings between the metal d-orbitals and pi-electrons of the hexaphyrin ring. Owing to these couplings, bis-Cu(II) and bis-Co(II) doubly N-confused hexaphyrins have much shorter excited-state lifetimes of 9.4 +/- 0.3 ps and 670 fs, respectively, than those (267 +/- 16 and 62.4 +/- 1.2 ps, respectively) of bis-Zn(II) and free-base doubly N-confused hexaphyrins. The two-photon absorption cross section (sigma(2)) values, which are believed to depend strongly on the ring planarity (pi-conjugation), are in line with the excited-state lifetime trends.

8.
J Am Chem Soc ; 128(12): 4119-27, 2006 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-16551121

RESUMO

Oxidation of a directly meso-meso linked cyclic porphyrin tetramer 2 gave a porphyrin sheet 3. The symmetric square structure of 3 is indicated by its simple 1H NMR spectrum that exhibits only two signals for the porphyrin beta-protons. The absorption spectrum of 3 displays characteristic Soret-like broad bands and weak Q-bands, and its magnetic circular dichroism (MCD) spectrum exhibits a negative Faraday A term at the 762 nm band as a rare case, indicating the absorption as a transition from a nondegenerate level to a degenerate level. A slightly longer S1-state (1.1 ps) and smaller TPA cross section (2750 GM) than a tetrameric linear porphyrin tape also indicate its unique electronic properties. The porphyrin sheet 3 forms stable 1:2 complexes with guest molecules G1 and G2, whose 1H NMR spectra exhibit remarkable downfield shifts for the guest protons that are located just above the cyclooctatetraene (COT) core of 3, whereas the imidazolyl protons bound to the zinc(II) porphyrin local cores are observed at slightly upfield positions. These results have been qualitatively accounted for in terms of the presence of a strong paratropic ring current around the COT core that propagates through the whole pi-electronic network of 3, hence competing with and cancelling the weak diatropic ring currents of the local zinc(II) porphyrins. This explanation was supported by DFT calculation performed at the GIAO-B3LYP/6-31G level, which indicated large positive NICS values within the COT core and small NICS values within the local zinc(II) porphyrins.

9.
J Am Chem Soc ; 128(5): 1700-4, 2006 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-16448144

RESUMO

Recently, covalently linked or self-assembled porphyrin array systems have attracted much attention for their enhanced two-photon absorption (TPA) behaviors. In this study, we have investigated the TPA properties of various dihedral angle controlled, directly linked porphyrin dimers and arrays to elucidate the relationship between the pi-conjugation pathway and TPA properties. We have demonstrated a strong correlation between pi-conjugation (aromaticity) and TPA properties in porphyrin assemblies.

10.
Chemistry ; 12(6): 1754-9, 2006 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-16311991

RESUMO

Treatment of hexakis(pentafluorophenyl)-substituted [26]hexaphyrin(1.1.1.1.1.1) (1) with CuCl in the presence of pyridine and molecular oxygen led to formation of doubly N-confused [26]hexaphyrin(1.1.1.1.1.1) 2 in a moderate yield through an unprecedented double pyrrolic rearrangement. Macrocycle 2 has been shown to serve as an effective bis-metal-coordinating ligand and exhibits attractive optical properties such as a sharp Soret-like band at 566 nm and low-energy fluorescence at 1058 nm.

11.
J Am Chem Soc ; 127(37): 12856-61, 2005 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-16159279

RESUMO

We have explored the electronic natures of representative expanded porphyrins, [26]- and [28]hexaphyrins, to investigate the interplay between the aromaticity and antiaromaticity that is brought by two electron oxidation/reduction processes. The excited singlet and triplet states of [26]hexaphyrin in solution exhibit lifetimes of 125 ps and 1.8 mus, respectively, as revealed by various time-resolved spectroscopic measurements. On the other hand, [28]hexaphyrin shows faster singlet and triplet lifetimes than those of [26]hexaphyrin, which is largely in accordance with the perturbation of aromaticity due to the pi electron formulation of [4n] in [28]hexaphyrins. The two-photon absorption cross-section values at 1200 nm for [26]hexaphyrins show ca. 9890 GM which is >10(2) larger than those of porphyrins. The reduced TPA values of 2600 and 810 GM of [28]hexaphyrin and perfluorinated [28]hexaphyrin, respectively, match well with their relatively short excited-state lifetimes. Overall, the enhanced excited-state lifetimes for various hexaphyrins go in line with the increased TPA cross-section values and the ring planarity.


Assuntos
Fótons , Porfirinas/química , Absorção , Estrutura Molecular , Fotoquímica , Termodinâmica , Fatores de Tempo
12.
Chem Commun (Camb) ; (30): 3782-4, 2005 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-16041415

RESUMO

Enlargement of the pi-electronic network of meso-meso, beta-beta, beta-beta triply linked diporphyrin has been exploited by preparing a corresponding dibenzo-fused porphyrin dimer that exhibits a perturbed absorption spectrum and a large two-photon absorption cross section.


Assuntos
Elétrons , Porfirinas/química , Adsorção , Dimerização , Modelos Moleculares , Estrutura Molecular , Probabilidade , Análise Espectral
13.
J Phys Chem A ; 109(13): 2996-9, 2005 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-16833622

RESUMO

The excited state dynamics and two-photon absorption properties of four novel triply linked porphyrin dimers in toluene have been investigated. The fused porphyrin dimers exhibit extremely increased two-photon absorption cross-section values (12,000-15,000 GM) compared with porphyrin monomers owing to much enhanced pi-electron delocalization throughout the porphyrin dimer ring.

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