Blood Lipid Components and SREBP-1 Gene Expression in Broiler Chickens Fed Different Dietary Lipid Sources

Background: Liver plays an important role in energy homeostasis. Intense liver diseases are accompanied with lower concentrations of n-3 and n-6 poly unsaturated fatty acids (PUFA). It has been found that n-3 PUFA play importantly protective roles in the liver. There was limited information about the effects of lipid sources on serum lipid components and liver sterol regulatory element binding-1 (SREBP-1) gene expression. Therefore, the aim of this study was to evaluate and compare the effects of fish oil, corn oil, olive oil and tallow, respectively, as dietary sources of n-3, n-6, n-9 and saturated fatty acid on serum lipid compound and liver SREBP-1 gene expression in broiler chicks.Materials, Methods & Results: In a completely randomized design, 240 one-day-old broiler chicks were allocated to five dietary treatments, four replicates and 12 chicks per each. Dietary treatments included of: control (diet without lipid supplementation) and diet supplemented with fish oil as a n-3 fatty acid source, corn oil as a n-6 fatty acid source, olive oil as a n-9 fatty acid source and tallow as a saturated fatty acid which were added to diets at 1.5, 3 and 4% in the starter, grower and finisher, respectively. At days 28 and 42 of age, liver tissue was dissected out and samples were placed in liquid nitrogen, also blood samples were collected. The SREBP-1 mRNA expression in liver tissue was quantitated using RT-PCR. Broilers fed diets containing fish oil, corn oil and olive oil as unsaturated fatty acid sources had lower concentrations of triacylglycerol than those fed other diets. Also, diets containing fish oil and tallow showed the lowest low density lipoprotein (LDL) levels at day 28 of age. Diets containing corn oil and olive oil showed higher levels of cholesterol and high density lipoprotein (HDL) than other diets but, these differences were not significant at days 28 and 42 of age  (P ≥ 0.05). In both sampling periods, the chickens fed diets containing tallow expressed higher (P < 0.05) SREBP-1 gene as compared to those fed other dietary lipids. Broilers fed diet containing corn oil had higher (P < 0.05) SREBP-1 gene expression than those fed diet containing fish oil and olive oil.Discussion: Serum lipids were affected by dietary fat source. Lower concentration of serum triacylglycerols was found in broilers fed fish oil and corn oil diets as dietary n-3 and n-6 fatty acid sources. It was shown that dietary PUFA, especially n-6 and n-3 fatty acids could reduce hepatic fatty acid and triacylglycerol synthesis. Broilers fed corn oil diet showed elevated LDL levels respect with those fed fish oil or tallow at day 28 of age. The results showed that dietary polyunsaturated fatty acids and saturated fatty acids substantially affected on SREBP-1 gene expression at days 28 and 42 of age. The birds fed fish oil as n-3 PUFA source expressed lower SREBP-1 gene compared with other groups at day 28 of age. Longer chain length, high number of double bonds, and the presence of the first double bond gives these fatty acids distinct and unique properties that separate them and their metabolic products from the more common n-6 and n-9 fatty acids. The finding of this study indicated lipogenic effects of tallow and then corn oil. The results confirmed that each of dietary lipid sources had different effect on serum lipid components. It was also found that SREBP-1 gene expression is age-dependent and it increased as age of broilers increased

Increase of Lysine Production in Corynebacterium glutamicum by using Gamma Irradiation

Corynebacterium glutamicum has been developed mostly by repeated random mutation and selection. In order to study the molecular mode of action on increase of lysine production in Corynebacterium glutamicum exposed to gamma rays at doses of 0,100, 200 and 300 Gy, mutant strain was selected first by bacteria counts and lysine production level, then it was used in molecular experiments. Wild and mutant strains of this bacteria were cultured in liquid media and proteins were extracted. Protein concentration was measured according to Bradford assay and sufficient amount of protein was loaded in Polyacrylamide gel electrophoresis. Electrophoresis of proteins was performed on 13% acrylamide running gel (1.0m

Correlation between condensed tannin and fiber contents of irradiated pomegranate seed

Pomegranate seeds were exposed to electron and gamma irradiations at doses of 5, 10, 15 and 20 kGy to study the relationships between their condensed tannin, NDF, ADF contents, in vitro rumen methane production and protozoa population. Data were analyzed by using the GLM procedure. Orthogonal contrast showed that gamma irradiation significantly increased the NDF content of pomegranate seed as compared to control (P<0.05), however electron beam irradiation did not significantly affect NDF%. The condensed tannin content of the pomegranate seed was significantly decreased by gamma and electron beam irradiation compared to control (P<0.05). Our results showed that there was a negative correlation between the methane production and NDF content of the gamma irradiated pomegranate seed. This means that the methane production of the gamma irradiated pomegranate seed decreased with increasing NDF%. Therefore, it seems that, in addition to tannin, the reduction of the methane production was affected by the cell wall content. Generally, the cell wall content may be more important than tannins in limiting microbial and in vitro fermentation

Blood Lipid Components and SREBP-1 Gene Expression in Broiler Chickens Fed Different Dietary Lipid Sources

Background: Liver plays an important role in energy homeostasis. Intense liver diseases are accompanied with lower concentrations of n-3 and n-6 poly unsaturated fatty acids (PUFA). It has been found that n-3 PUFA play importantly protective roles in the liver. There was limited information about the effects of lipid sources on serum lipid components and liver sterol regulatory element binding-1 (SREBP-1) gene expression. Therefore, the aim of this study was to evaluate and compare the effects of fish oil, corn oil, olive oil and tallow, respectively, as dietary sources of n-3, n-6, n-9 and saturated fatty acid on serum lipid compound and liver SREBP-1 gene expression in broiler chicks.Materials, Methods &amp; Results: In a completely randomized design, 240 one-day-old broiler chicks were allocated to five dietary treatments, four replicates and 12 chicks per each. Dietary treatments included of: control (diet without lipid supplementation) and diet supplemented with fish oil as a n-3 fatty acid source, corn oil as a n-6 fatty acid source, olive oil as a n-9 fatty acid source and tallow as a saturated fatty acid which were added to diets at 1.5, 3 and 4% in the starter, grower and finisher, respectively. At days 28 and 42 of age, liver tissue was dissected out and samples were placed in liquid nitrogen, also blood samples were collected. The SREBP-1 mRNA expression in liver tissue was quantitated using RT-PCR. Broilers fed diets containing fish oil, corn oil and olive oil as unsaturated fatty acid sources had lower concentrations of triacylglycerol than those fed other diets. Also, diets containing fish oil and tallow showed the lowest low density lipoprotein (LDL) levels at day 28 of age. Diets containing corn oil and olive oil showed higher levels of cholesterol and high density lipoprotein (HDL) than other diets but, these differences were not significant at days 28 and 42 of age  (P ≥ 0.05). In both sampling periods, the chickens fed diets containing tallow expressed higher (P &lt; 0.05) SREBP-1 gene as compared to those fed other dietary lipids. Broilers fed diet containing corn oil had higher (P &lt; 0.05) SREBP-1 gene expression than those fed diet containing fish oil and olive oil.Discussion: Serum lipids were affected by dietary fat source. Lower concentration of serum triacylglycerols was found in broilers fed fish oil and corn oil diets as dietary n-3 and n-6 fatty acid sources. It was shown that dietary PUFA, especially n-6 and n-3 fatty acids could reduce hepatic fatty acid and triacylglycerol synthesis. Broilers fed corn oil diet showed elevated LDL levels respect with those fed fish oil or tallow at day 28 of age. The results showed that dietary polyunsaturated fatty acids and saturated fatty acids substantially affected on SREBP-1 gene expression at days 28 and 42 of age. The birds fed fish oil as n-3 PUFA source expressed lower SREBP-1 gene compared with other groups at day 28 of age. Longer chain length, high number of double bonds, and the presence of the first double bond gives these fatty acids distinct and unique properties that separate them and their metabolic products from the more common n-6 and n-9 fatty acids. The finding of this study indicated lipogenic effects of tallow and then corn oil. The results confirmed that each of dietary lipid sources had different effect on serum lipid components. It was also found that SREBP-1 gene expression is age-dependent and it increased as age of broilers increased

Comparing the Effect of Ionizing Radiations of Electron Beam and Gamma Ray on Ruminal Degradation Kinetics of Soybean Meal Protein and Amino acids

This research was conducted to compare effects of electron beam (EB) and gamma ray (GR) treatments at doses of 25, 50 and 75 kGy on soybean meal (SBM) ruminal degradation kinetics of crude protein (CP) and amino acids (AA). The nylon bag and sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) techniques were used for this aim. Ionizing radiations decreased washout and degradation rate fractions and increased potentially degradable fraction of CP. GR had more effects on degradability parameters of CP than the EB. Irradiation processing caused decreasing in AA degradation after 16 h of ruminal incubation significantly. GR irradiation was more effective than EB irradiation in lessening the ruminal degradability of AA. In unirradiated SBM, subunits ά, α and β of β-conglycinin protein disappeared after 4 h, and basic and acidic subunits of glycinin protein disappeared after 16 h of rumen incubation. The 50 and 75 kGy doses of EB and GR maintained and preserved the subunits of β-conglycinin until 16 h and 48 h for glycinin subunits. The results of this study showed greater effects of GR than the EB in reducing the ruminal degradation of CP and AA, while the ruminal disappearance of the protein subunits in the SBM was equally affected by these ionizing radiations

Effects of replacing fish meal with irradiated chickpea in diet on growth performance, body compositions and apparent digestibility of rainbow trout (Oncorhynchus mykiss)

This study aimed to introduce new protein sources to replace fish powder in diets for rainbow trout, Oncorhynchus mykiss. In this study, fish powder protein was replaced with the typical Kabuli chickpea (Cicer arietinum) and irradiated pea seeds in the diet followed by assessing their effects on growth and nutritional indices, digestion and body composition of rainbow trout. The study was conducted in the Artemia and Aquatics Propagation Research Institute, University of Urmia, Urmia, Iran. 720 juvenile O. mykiss (60 ± 4 g) were randomly divided equally into eight treatments with three replicates, and were fed with experimental diets for 60 days. The experimental diets were commercial food, homemade food without pea (control), typical pea diets containing 20, 30 and 40% and diets containing 20, 30 and 40% irradiated pea. The results showed that radiation has not significantly affected the food ingredients of peas (protein, fat and dry matter) and growth parameters (P>0.05), but there were significant changes in nutritional indicators and digestibility of the diet along with increasing the percent of peas replacement (P<0.05). As a result, the increase in radiation as well as 40% peas in the diet of O. mykiss did not exhibit negative impact on growth performance. Therefore, the irradiated pea protein can be a good food item to replace fish powder in the fish diet