جستجوی مقالات مرتبط با کلیدواژه "unsaturated fatty acid" در نشریات گروه "علوم دام"

Based on current knowledge, it has been proven that many edible ingredients in addition to meeting the needs of creatures, in terms of energy and protein, contain compounds that affect cellular actions and intracellular signaling pathways and can temporarily or permanently change the function of the cell. The use of molecular biology tools and genetic research defines the mechanisms through which gene expression is affected by food, and conversely, these genes also affect the absorption of food, metabolism, and excretion. From the point of view of nutrigenomics, dietary nutrients are signals that are received by sensitive cell systems and can affect the expression of genes and proteins and the production of metabolites. Nutritional manipulations and strategies are key tools to influence ruminant production. Fatty acids act on the nucleus by binding to and regulating the activity of specific nuclear receptors or transcription factors, thus playing a central role in regulating the expression of genes involved in fatty acid uptake by muscle cells. Interactions between diet nutrients and the expression of genes involved in lipid metabolism have many possibilities regarding the deposition of fatty acids in the tissue. The study of gene expression has enabled clarification of the mode of fatty acid metabolism in muscle and the accumulation of intramuscular fat or marbling and the role of the genes that promote fatty acid oxidation and mitochondrial respiration in the liver muscle and adipose tissue. Polyunsaturated fatty acids with multiple double bonds (PUFA) and monounsaturated fatty acids with one double bond (MUFA) have received much attention in the last decade, and their health benefits are increasingly evident. Therefore, this study investigated the effect of using calcium salts of fish oil, olive oil, and saturated fat on the expression of some genes related to fat metabolism in Lori Bakhtiari×Romanov fattening lambs.
This study was carried out at the educational research station of the Department of Animal Science of the College of Agriculture and Natural Resources, University of Tehran. 49 male lambs aged four to five months with an average initial weight of 29.97 ± 0.88 kg were divided into seven groups of seven lambs in a completely randomized design. The experiment consisted of seven treatments with a basic diet as follows: 1) Basic diet without fat powder (control), 2 and 3) Basic diet with calcium salt of fish oil (rich in omega-3 fatty acids) in the amount of 2% dry matter of the diet for 90 and 45 days, respectively, 4 and 5) Basic diet with calcium salt of olive oil (rich in omega-9 fatty acids) at the rate of 2% dry matter of the diet for 90 and 45 days, respectively, 6 and 7) Basic diet with saturated fat powder in the amount of 2% dry matter of the diet for 90 and 45 days, respectively. Rations were adjusted based on the NRC Sheep and Goat and using the fifth version of CNCPS (The Cornell Net Carbohydrate and Protein System) software so that they are the same in terms of energy and protein. Twenty-eight lambs were slaughtered and a liver sample was taken for nutrigenomics studies. Total RNA was extracted from liver tissue samples using the RNA extraction kit produced by Dena Bio Asia Company (Mashhad) and according to the protocol provided with the kit. The expression of four main genes involved in lipid metabolism in liver tissue was investigated to provide comprehensive information on the effects of omega-3, omega-9 fatty acids, and saturated fat at the molecular level.
The results showed that feeding with calcium salts of fish oil, olive oil, and saturated fat, both in the whole 90 days or the last 45 days of the fattening period, had no significant effect on the expression of FADS1 and FADS2 genes in liver tissue compared to the control group. However, the use of calcium salts of fish and olive oils in periods of 90 and 45 days significantly increased the hepatic mRNA expression of the CPT1 gene (P=0.001) and ACOX1 gene mRNA expression in liver tissue compared to control and saturated fat treatments (P=0.002). The CPT1 enzyme is responsible for a mitochondrial transport system and plays a key role in controlling the oxidation of long-chain fatty acids and stimulating mitochondrial β-oxidation.
The results of this study showed that diet supplementation with calcium salts of fish and olive unsaturated fatty acids, regardless of the period of consumption, increased the expression of genes involved in the lipolysis of liver tissue fats of lambs.

 Raising healthy calves is indeed a critical concern in the dairy industry. Close up diets have important effects on the quantity and quality of produced colostrum, on the other hand, colostrum and milk are considered the most important sources of food that contain energy, protein, and other nutrients for the newborn calf’s growth. Including fatty acids in the late pregnancy supplements are controversial because of the potential reduction of cows DMI. Also, the growth and health of calves can be influenced by feeding linoleic acid to pregnant cows. Safflower as a rich source of linoleic acid (55-70%) is a significant oil alternative product, and has a high nutritional value. This study aimed to examine the effects of safflower seeds and palmitic fatty acids on the transition diet in cow feed consumption, colostrum quality, blood parameters, body measurements and Holstein calf performance.

Materials and methods :

Thirty pregnant Holstein cows, 15 primiparous and 15 multiparous, were used 21 days prior to the expected calving date. The experiment was conducted using a completely randomized experimental design with three treatments and ten replicates in every treatment. Cows were randomly assigned to experimental treatments so that each treatment have an average body weight 659.34 ± 84.2 kg, parity 2.04 ± 1.31 and body condition score (BCS) 3.23 ± 0.15 The experimental rations have similar energy and protein content. Diets were thoroughly mixed and fed to cows based on the recommendations of the US National Research Council (NRC, 2001). The experimental rations included: 1) Control diet without fat source (Ctrl), 2) Diet with palmitic fatty acid (SFA), and 3) Diet with safflower seed (UFA). Daily feed intake was calculated by subtracting distributed feed to every cow from the leftover amount on following day. Newborn calves were weighed immediately after birth. An individual colostrum yield for every cow was recorded at each milking. The quality of colostrum was determined using an optical refractometer (ATC., China). The body weight and skeletal parameters of calves were evaluated at birth day, 21 d, and 49 d. Blood samples were taken immediately after birth, two hours after colostrum feeding and on days 3, 7, 21, and 49 via the jugular vein. Samples were centrifuged at 3000× g and the plasma was stored at −20°C until analysis. Plasma metabolites were analyzed using an autoanalyzer (Alcyon 300., USA). Colostrum composition (fat, protein, lactose, solids, solids not fat) was determined using a Milkoscan (Foss Electric, Hillerød, Denmark). Fatty acids profile were measured according to O'Fallon (2007) et al., using gas chromatography (GC) equipped FID detector and 100 meter column. Data were analyzed using the MIXED procedure of SAS using a completely randomized design with ten replications.

  Results and Discussion:

 Using sources of SFA (palm oil powder) and UFA (safflower seeds) in the transition diets were not affected on dry matter intake in Holstein dairy cows (P>0.05). Dry matter intake in Ctrl, SFA, and UFA were 10.29, 10.98, and 10.80 kg per day, respectively. We found that  using SFA and UFA did not have any significant effect on colostrum parameters such as colostrum volume, the percentage of fat, protein, lactose, total solids, fat not solids, and also, immunoglobulin concentration, and Brix number of colostrum (P>0.05). The colostrum volume in UFA and SFA treatments was higher than in the Ctrl treatment, but this difference was not significant (5.82, 5.23, and 4.19 kg, respectively). According to the results, the researchers stated that adding raw and processed safflower seeds to the diet did not have any significant effect on milk production, milk fat, protein, and lactose in Holstein dairy cows (Paya and Taghizadeh, 2020). Feeding omega-6 sources in the transition period (35 days before calving) caused higher colostrum protein and Brix values (Salehi et al., 2016) but was not consistent with our results. Feeding palm fat powder as a source of SFA and safflower seeds as UFA did not have any significant differences in concentration of short chain, medium chain, and long chain fatty acids in colostrum. It was reported that various fat sources in the rations of dairy and transition cows did not affect colostrum fatty acid and milk fatty acid. However some studies showed that different fat sources in the diet of dairy cows changed the fatty acid profile in milk. In general, it can be stated that because of the high-producing dairy cows experience a negative energy around calving, the diet energy meets the requirements, which probably causes the fatty acid composition of the colostrum not to be affected. Our results showed that blood factors such as glucose, cholesterol, triglycerides, blood urea nitrogen, ALT, AST, total antioxidant capacity, malondialdehyde, total protein, albumin, calcium, magnesium, phosphorus, and HDL did not differ between treatments. It was observed that the addition of SFA and UFA had no significant effect on the birth weight of calves, weight at d 21 and 49, and dry matter intake during the experimental period. Skeletal parameters such as hip height and width, withers height, chest circumference, and body length at 3, 21, and 49 days had no significant differences in the treatments.

  Conclusion:

 It seems that using saturated and unsaturated fatty acids sources in the transition diets did not reduce feed intake. Moreover, it had no significant influence on the calves' performance, bone condition, the colostrum's quality and the colostrum fatty acids profile.

To determine the effects of addition of the protected saturated and unsaturated fats on performance, blood and rumen parameters of Holstein suckling calves an experiment using 40 newborn calves (20 females and 20 males) with 5±2 days old and an average weight of 35±2 kg after colostrum administration was carried out in a completely randomized design with four treatments and 10 replicate for 70 days. Experimental groups included: 1) control diet, without fat supplementation, 2) diet with 2% calcium-unsaturated fatty acid supplementation, 3) diet with 2% calcium-unsaturated fatty acid supplementation, and 4) diet with an equal mixture 1% of both were complemented. In order to evaluate changes in body weight, chest circumference and height, the data were measured and recorded weekly at 10 a.m. To determine the blood parameters, blood samples were taken from the jugular vein on the 30th and 70th days experiment. The results of this study showed that the addition of unsaturated and unsaturated fat supplements did not have a significant effect on calves' performance so that weight gain, feed intake, feed efficiency and fecal index were not significantly different in experimental groups. Also, skeletal growth of calves was not affected by dietary fat supplementation. Dietary supplementation significantly affected the digestibility of the diet (p<0.05). The digestibility of dry matter, organic matter and neutral detergent fiber was higher in all experimental groups receiving fat supplement than the control group (p<0.05). The highest fat digestibility was in the experimental group containing unsaturated fatty acids. Fat supplementation had no significant effect on ruminal fluid and blood parameters of calves. Due to the uniformity of energy and crude protein in the experimental diets, it was expected that the most important factor in the possible improvement of calf performance was the positive effect of these supplements on the digestibility of the diet and the biological role of fatty acids, especially in health. The results of this study showed a positive effect of supplements on digestibility, but these changes may not be large enough to affect feed efficiency and weight gain in calves.

This experiment was carried out to compare the effects of different levels of unsaturated fatty acid supplementation in the starter diet on daily weight gain and metabolic parameters of Ghezel lambs. Twenty male lambs were breastfeed for 4 weeks and randomly divided into 4 groups of 5 animals in a complete randomized design. After 2 weeks of adaptation, they were fed starter diets supplemented with different levels of protected unsaturated fatty acids. Experimental diets were of starter diet with concentrate to forage ratio of 90:10, supplemented with different levels of rumen protected PUFA ca-salts. Treatments were including control (breast fed lambs) and experimental groups were fed starter diets supplemented with 3, 4.5 and 6 percent of lipid supplement. The effect of treatments on dry matter intake and live weight gain were significant. The highest amount of feed intake and weight gain were observed in 3% fat supplemented group. The highest NDF, ADF, OM and CP digestibility was observed in 3% fat supplemented concentrate but crude fat digestibility was not affected by treatments. The amount of acetic acid in all treatments showed a significant difference compared with each other and increased with increasing fat percentage in the diet. The ratio of acetic acid to propionic acid shows a significant decrease upon fat supplementation. Plasma glucose and total protein levels significantly increased and triglycerides decreased in fat supplementation groups compared with control. Generally, early weaning with 3% of protected fat supplemented diet increased lamb growing performance without negative health issues.

The aim of this study was to determine effects of dietary high-linoleate seed (soybean) and high-oleate seed (canola) on blood metabolites and growth parameters of lambs fed diets containing different levels of energy and protein. Thirty male Afshari lambs were used to evaluate the effects of two dietary energy and protein levels (2.3 Mcal/kg metabolisable energy (ME), 14% crude protein (CP) and 2.7 Mcal/kg ME, 16.4% CP) and different levels of each oil seed (no seed, 5% soybean, 10% soybean, 5% canola, 10% canola) on blood metabolites and growth parameters. Lambs were randomly allotted to 10 dietary treatments as a 2×5 factorial arrangement. Diets were fed ad libitum for 84 days, after 14 days of adaptation. Feed intake was recorded daily and weight gain and blood metabolites were determined once each 14 and 28 days, respectively. The results showed that increasing dietary contents of CP and ME increased feed intake, growth rate, protein efficiency ratio and improved feed conversion ratio. Using 5% soybean seed in the high energy and protein diet resulted in a higher feed intake, gain and final weight (P<0.05). Serum glucose, cholesterol and low density lipoproteins were not altered, but serum high density lipoprotein was higher and albumin, triglycerides and very low density lipoprotein were lower in the lambs fed with oilseeds rich in unsaturated fatty acids (P<0.05). Finally, it was seen that supplementation of 5% soybean seed in high density diet had a positive effect on performance of growing lambs.