RESUMEN
This study aimed to elucidate the effects of broiler embryos soaked in ferulic acid (FA) solution on alleviating the negative impact of thermal manipulation (TM) on chicken embryo development and to provide a theoretical and experimental basis for applying TM and FA in the poultry feeding industry. A total of 120 broiler fertilized eggs were randomly divided into three groups: control group, TM group, and comprehensive group (TM + FA), with 40 eggs in each group. The TM group and the comprehensive group from the 7th embryonic age to the 16th embryonic age received TM for ten days, treated with a temperature of 39.5 °C and relative humidity of 65% for 18 h a day. In the comprehensive group, broiler embryos were immersed in FA solution at a concentration of 80 mg/L for 6 min at 16:00 every day from the 6th to the 8th embryo age. They were incubated continuously after being soaked until the chicks hatched. The results showed that the rates of dead embryos and weak chicks in the TM group were significantly higher than those in the control group and comprehensive group. Chick body temperatures of the TM group and comprehensive group were significantly lower than those of the control group. The heart weights of the TM group and comprehensive group were significantly lower than those of the control group, and the leg weights of the TM group were significantly decreased compared with those of the control group and comprehensive group. The SOD activity of serum in the comprehensive group was significantly higher than that in the control group and TM group, while the CAT activity of serum in the comprehensive group and control group was significantly higher than that in the TM group; however, there was no difference between the comprehensive group and control group. The activities of SOD and CAT in the liver were significantly higher than those of the TM group; however, the MDA content of the liver in the comprehensive group and control group was significantly lower than that of the TM group. The gene expression of Nrf2 and SOD in the comprehensive group and TM group was significantly higher than that in the control group; however, there was no significant difference between the comprehensive group and TM group. Soaking broiler embryonic eggs in an FA solution can improve the antioxidant capacity of the liver by upregulating Nrf2-Keap1 signal pathway-related gene expression. FA can effectively alleviate the side effects of TM on chicken embryos and does not impact the effects of TM.
Asunto(s)
Antioxidantes , Pollos , Ácidos Cumáricos , Desarrollo Embrionario , Animales , Ácidos Cumáricos/farmacología , Embrión de Pollo/efectos de los fármacos , Desarrollo Embrionario/efectos de los fármacos , Antioxidantes/farmacología , Antioxidantes/metabolismoRESUMEN
Glucocorticoids (GCs) are an essential mediator hormone that can regulate animal growth, behavior, the phenotype of offspring, and so on, while GCs in poultry are predominantly corticosterones. The biological activity of GCs is mainly regulated by the intracellular metabolic enzymes, including 11ß-hydroxysteroid dehydrogenases 1 (11ß-HSD1), 11ß-hydroxysteroid dehydrogenases 2 (11ß-HSD2), and 20-hydroxysteroid dehydrogenase (20-HSD). To investigate the embryonic mechanisms of phenotypic differences between breeds, we compared the expression of corticosterone metabolic enzyme genes in the yolk-sac membrane and chorioallantoic membrane (CAM). We described the tissue distribution and ontogenic patterns of corticosterone metabolic enzymes during embryonic incubation between Tibetan and broiler chickens. Forty fertilized eggs from Tibetan and broiler chickens were incubated under hypoxic and normoxic conditions, respectively. Real-time fluorescence quantitative PCR was used to examine the expression of 11ß-HSD1/2, and 20-HSD mRNA in embryonic tissues. The results showed that the expression levels of yolk-sac membrane mRNA of 11ß-HSD2 and 20-HSD in Tibetan chickens on E14 (embryonic day of 14) were significantly lower than those of broiler chickens (P < 0.05), and these genes expression of CAM in Tibetan chickens were higher than those of broiler chickens (P < 0.05). In addition, the three genes in the yolk-sac membrane and CAM were followed by a down-regulation on E18 (embryonic day of 18). The 11ß-HSD1 and 11ß-HSD2 genes followed a similar tissue-specific pattern: the expression level was more abundantly in the liver, kidney, and intestine, with relatively lower abundance in the hypothalamus and muscle, and the expression level of 20-HSD genes in all tissues tested was higher. In the liver, 20-HSD of both Tibetan and broiler chickens showed different ontogeny development patterns, and hepatic mRNA expression of 20-HSD in broiler chickens was significantly higher than that of Tibetan chickens of the same age from E14 to E18 (P < 0.05). This study preliminarily revealed the expression levels of cortisol metabolic genes in different tissues during the development process of Tibetan and broiler chicken embryos. It provided essential information for in-depth research of the internal mechanism of maternal GCs programming on offspring.
Asunto(s)
Pollos , Corticosterona , Animales , Embrión de Pollo , Corticosterona/metabolismo , Pollos/genética , Pollos/metabolismo , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 2/genética , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 2/metabolismo , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/genética , 11-beta-Hidroxiesteroide Deshidrogenasa de Tipo 1/metabolismo , Tibet , Glucocorticoides/metabolismo , Hidroxiesteroide Deshidrogenasas/genética , Hidroxiesteroide Deshidrogenasas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , Expresión GénicaRESUMEN
In this study, the effects of 5 graded dietary levels (0.025, 0.05, 0.075, 0.1, and 0.125%) of dimethylglycine (DMG) were studied in laying hens during the late laying period (71-78 wk). Graded doses of DMG from 0.025 to 0.125% in the diet produced quadratic positive (P < 0.05) responses in the laying rate, egg-feed ratio, yolk color, grade follicular weight, and the number of large white follicles and linear positive (P < 0.05) responses in average egg weight, and the number of large white follicles. With 0.1% DMG, the laying rate and egg-feed ratio improved (P < 0.05), and the abdominal fat percentage decreased. Considering the laying performance under the conditions used in this study, the best-fit model for the DMG requirements of laying hens was estimated to range from 0.049 to 0.065% DMG during the late laying period based on a regression analysis. The addition of DMG did not affect the total cholesterol (TCH) and triglyceride (TG) contents in the plasma of laying hens; however, it significantly reduced the abdominal fat rate. DMG may change the course of lipid deposition in laying hens during the late laying period. In conclusion, supplementation with DMG can improve the laying rate and follicles development of laying hens.
Asunto(s)
Alimentación Animal , Pollos , Alimentación Animal/análisis , Animales , Dieta/veterinaria , Suplementos Dietéticos , Yema de Huevo , Femenino , Óvulo , Sarcosina/análogos & derivadosRESUMEN
Fat mass and obesity-associated (FTO) gene is widely expressed in central and peripheral tissues of mammals, and exhibits a range of functions, especially in energy balance. However, basic knowledge of FTO in the chicken is lacking. Therefore, we studied the tissue distribution, age and breed dependent changes, brain localization, as well as the impact of fasting on FTO mRNA expression in the chicken. FTO mRNA was expressed in all the tissues studied, and generally, with high expression in hypothalamus, liver, visceral fat and cerebellum. However it exhibited breed-specific patterns: in broilers, the highest expression was seen in the liver, while in layers, hypothalamus and cerebellum showed relatively higher FTO mRNA expression. One-week-old broilers expressed markedly higher FTO mRNA in liver compared with the layers of the same age (P<0.01), while the breed difference was reversed in visceral fat and cerebellum (P<0.05). Compared with newly hatched chicks (one week of age), adult layers expressed higher FTO mRNA in liver and visceral fat, while adult broilers showed higher expression in hypothalamus and cerebellum. In situ hybridization demonstrated distribution of FTO mRNA in paraventricularis magnocellularis (PVN), nucleus ventromedialis hypothalami (VMN), nucleus lateralis hypothalami (LHy), nucleus dorsomedialis hypothalami (DMN) of the hypothalamus and nucleus habenularis medialis (HM) and stratum cellulare externum (SCE) of the thalamus. Breed-specific expression of FTO mRNA was shown in PVN, but not in VMN, with higher abundance in broilers compared to layers. The decrease in FTO mRNA levels after 24h of fasting was seen only in VMN of layer chickens. These results may provide some intriguing hints for further investigation of FTO function in the chicken.
Asunto(s)
Proteínas Aviares/genética , Cerebelo/metabolismo , Pollos/genética , Hipotálamo/metabolismo , Tálamo/metabolismo , Análisis de Varianza , Animales , Proteínas Aviares/metabolismo , Pollos/metabolismo , Ayuno , Regulación del Desarrollo de la Expresión Génica , Hibridación in Situ , Grasa Intraabdominal/metabolismo , Hígado/metabolismo , Masculino , Especificidad de Órganos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la PolimerasaRESUMEN
The study was conducted to investigate the effect of early feed restriction (ER) on lipid metabolism and mitochondrial function in the liver of broiler chickens. Newly hatched broiler chickens were randomly allocated into control and ER group which was subjected to feed restriction with feed provided on alternate days from hatch to 14 days of age (14 d), followed by ad libitum feeding until the end of the experiment on 63 d. ER group exhibited significantly lower body weight throughout the experiment. Serum concentrations of total cholesterol (TC) and high density lipoprotein cholesterol (HDLC) were significantly higher in ER group at 14 d (P<0.05), and the higher serum TC level in ER group was also observed at 63 d. In contrast, the contents of triglyceride (TG), TC and lipoprotein lipase (LPL) activity in liver were significantly lower in ER group at 14 d (P<0.05). At 14 d no significant difference was detected for the mRNA expression of the acetyl-CoA carboxylase-α (ACC-α), carnitine palmitoyltransferase I (CPT-I), sterol regulatory element binding protein-1c (SREBP-1c) or peroxisome proliferator-activated receptors α (PPAR-α) between control and ER group. At 63 d ACC-α mRNA expression was significantly down-regulated accompanied with a significantly up-regulated CPT-ImRNA and a decreased tendency of SREBP-1c mRNA expression in ER group (P=0.09). Swollen mitochondria with fragmented and reduced cristae were observed in liver of ER group at 14 d. Meanwhile the inner mitochondria membrane viscidity increased and hepatic mitochondrial superoxide dismutase (SOD) activity decreased at 14 d. The results suggest that feed restriction at early postnatal stage may produce long-term effect on lipid metabolism of broiler chicken, probably through, at least in part, alterations in mitochondria morphology and function.
Asunto(s)
Pollos/metabolismo , Privación de Alimentos/fisiología , Regulación de la Expresión Génica/fisiología , Metabolismo de los Lípidos/fisiología , Acetil-CoA C-Acetiltransferasa/metabolismo , Animales , Carnitina O-Palmitoiltransferasa/metabolismo , Pollos/fisiología , Colesterol/sangre , HDL-Colesterol/sangre , Lipoproteína Lipasa/metabolismo , Fluidez de la Membrana , Mitocondrias Hepáticas/metabolismo , Mitocondrias Hepáticas/fisiología , Membranas Mitocondriales/metabolismo , PPAR alfa/metabolismo , ARN Mensajero/metabolismo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/veterinaria , Proteína 1 de Unión a los Elementos Reguladores de Esteroles/sangre , Superóxido Dismutasa/metabolismo , Triglicéridos/sangreRESUMEN
The present study was aimed to investigate the mechanism underlying the influence of maternal low-protein (LP) diet on offspring growth in the chicken. One hundred and twenty Chinese inbred Langshan breeder hens were allocated randomly into two groups fed diets containing low (10%, LP) or normal (15%) crude protein levels. Low dietary protein did not affect the body weight of hens, but significantly decreased the laying rate and egg weight. The yolk leptin content was significantly lower in eggs laid by LP hens, while no differences were detected for yolk contents of corticosterone, tri-iodothyronine (T3) or thyroxine. Despite significantly lower hatch weight, the LP offspring demonstrated obviously higher serum T3 concentration, which is in accordance with the faster post-hatch growth rate achieving significantly heavier body weight and pectoralis major muscle weight 4 weeks post-hatching. Expression of 20-hydroxysteroid dehydrogenase (20-HSD) mRNA in the yolk-sac membrane was significantly down-regulated at embryonic day 14, whereas that of transthyretin and leptin receptor (LepR) was not altered. Moreover, hypothalamic expression of 20-HSD, glucocorticoid receptors, thyrotropin-releasing hormone and LepR mRNA was significantly up-regulated in the LP group compared with their control counterparts. In the pectoralis major muscle, significantly higher expression of insulin-like growth factor (IGF)-I and IGF-I receptor mRNA was observed in LP embryos. The present study provides evidence that maternal LP diet programmes post-hatch growth of the offspring. The associated alterations in yolk leptin deposition as well as in yolk-sac membrane, fetal hypothalamus and muscle gene expression may be involved in mediating such programming effect in the chicken.