Dietary polyunsaturated fat reduces skin fat as well as abdominal fat in broiler chickens

The impacts of dietary inclusion of soybean oil and linseed oil on growth performance, carcass yield, and health status of growing Japanese quail

Polyunsaturated fatty acids (PUFA), including n-6 and n-3 fatty acids, are essential for enhancing the performance and health of poultry. Avian species lack desaturase enzymes for endogenous synthesis of n-6 and n-3 fatty acids. This work aimed to determine the impacts of including soybean oil (SO) and linseed oil (LO) in quail diets on growth, lipid profile, hepatic and renal functions, immunity, and antioxidant status. A total of 350 Japanese quail chicks (1-wk-old) were randomly arranged into 7 dietary treatment groups. Seven isocaloric and isonitrogenous experimental basal diets were formed based on the nutritional requirements of growing Japanese quail. Group 1, the control, received a basal with no oils, while groups 2 to 7 received a basal diet containing either 1% SO, 1.5% SO, 2% SO, 1% LO, 1.5% LO, or 2% LO, respectively. Quail groups that consumed diets containing LO at all levels showed significantly greater live body weight (LBW) at 5th wk of age than other experimental groups. The dietary incorporation of 1.5 or 2% SO or LO at all levels yielded significant improvements in body weight gain (BWG) and feed conversion ratio (FCR) through 3 to 5 and 1 to 5 wk of age. Different dietary oil sources and levels have no significant impacts on feed intake (FI) and carcass yield parameters. Lipid profile parameters were improved by adding SO and LO in quail diets, with LO having a higher effect than SO. The hepatic and renal functionality were improved by adding SO and LO in quail diets. The lowest uric acid (UA) bloodstream concentrations were recorded in the quail group fed a diet with 2% LO. Values of Gamma globulins (G-GLO) and immunoglobulins (G, M, and A) were increased by adding SO or LO to quail diets. Blood levels of MDA and TAC were improved significantly by including LO in quail diets. The activity of the superoxide dismutase (SOD) enzyme was significantly increased by adding SO or LO to quail diets. Generally, adding SO or LO to growing quail diets up to 2% could yield favorable effects on growth performance, blood lipids, hepatic and renal functions, immunity, and antioxidant status; however, LO seems to have better effects than SO.

Impact of Dietary Supplementation with Sodium Butyrate Protected by Medium-Chain Fatty Acid Salts on Gut Health of Broiler Chickens

Simple Summary

Nutritional strategies to improve gut health are under research to reduce antibiotic use in poultry production. This study investigated the effect of dietary supplementation with sodium butyrate protected by sodium salts of medium-chain fatty acids as a feed additive on broiler gut health. A first trial was conducted to assess the effectiveness of this feed additive supplemented at a dose range of 0.5, 1, and 2 kg/t to promote a good health status on broilers raised under optimal conditions. Supplementation at 0.5 and 1 kg/t maintained the number of mucin-secretory cells contained in the gut barrier of young chickens, and the use of 1 kg/t improved the intestinal immune system of aged broilers. However, the beneficial effects of some feed additives are not detected under non-challenged conditions. Therefore, the second experiment was performed to evaluate the effect of the feed additive at 1 kg/t in coccidiosis-challenged broilers. In this context, sodium butyrate protected by sodium salts of medium-chain fatty acids restored the number of mucin-secretory cells as well as impacted on the intestinal morphometry and microbiota. The results of the present study suggest that this feed additive could be a useful strategy to reinforce the gut barrier, especially for birds with coccidiosis.

Abstract

Nutritional strategies to improve gut health of broilers are under research. This study investigated the effect of dietary supplementation with sodium butyrate protected by sodium salts of medium-chain fatty acids as a feed additive on broiler gut health. The first experiment was conducted to evaluate the effect of supplementing at 0.5, 1, and 2 kg/t in broilers housed under optimal conditions. Supplementation at 0.5 and 1 kg/t maintained goblet cell counts at 10 days of age (p ≤ 0.05), and supplementation at 1 kg/t decreased intraepithelial lymphocyte counts compared to 2 kg/t at 39 days (p ≤ 0.10). Abdominal fat pad levels of lauric and myristic acids were gradually increased by supplement dose (p ≤ 0.05). In the second experiment, the feed additive at 1 kg/t was evaluated in coccidiosis-challenged broilers. Experimental treatments were as follows: non-challenged, control-challenged, and supplemented-challenged treatments. Coccidiosis negatively impact performance and modify histomorphometry and microbiota (p ≤ 0.05). The feed additive increased crypt depth at 7 days post-inoculation and goblet cell count at 14 days post-inoculation (p ≤ 0.05). Further, supplementation interacted with the microbiota modification led by the coccidiosis (p ≤ 0.05). These results suggest that this feed additive could be a useful strategy to reinforce the gut barrier, especially for birds under coccidiosis-challenge treatments.

Olive pomace oil and acid oil as alternative fat sources in growing-finishing broiler chicken diets

The aim of the present study was to investigate the effect of dietary supplementation of olive pomace oil and olive pomace acid oil, which are rich in monounsaturated fatty acids (FA) but differ in free FA content, on growth performance, digestibility and FA profile of abdominal fat and breast meat. A total of 3,048 one-day-old mixed-sex broiler chickens (Ross 308) were randomly distributed into 24 pens and 3 dietary treatments (8 replicates per treatment). Experimental diets were administered for growing (from 22 to 29 d) and finishing (from 30 to 39 d) periods, consisting of a basal diet supplemented with 6% (as-fed basis) palm oil (PO), olive pomace oil (O), or olive pomace acid oil (OA). Animals fed O achieved the lowest feed conversion ratio (P < 0.01), together with the highest AME value (P = 0.003), but no differences were observed between OA and PO. Regarding FA digestibility, O and OA showed higher values than PO for all FA in both apparent ileal digestibility (AID) and apparent total tract digestibility. Comparing the AID between O and OA, no differences were observed for total FA, monounsaturated FA, or polyunsaturated FA, but animals fed OA showed lower AID values for saturated FA than those fed O (P < 0.001). The FA profile of abdominal fat and breast meat reflected that of the diet, with higher monounsaturated FA and lower saturated FA in animals fed O and OA compared to those fed PO. In sum, the inclusion of both olive pomace oil and acid oil in growing-finishing broiler chicken diets led to great performance parameters and high FA digestibility values, together with an enrichment with monounsaturated FA in abdominal fat and breast meat compared to the use of palm oil. However, a better AID of saturated FA and feed conversion ratio is achieved with O compared to OA.

Effects of Dietary Thraustochytrid schizochytrium sp. and Other Omega-3 Sources on Growth Performance, Carcass Characteristics, and Meat Quality of Broilers

Simple Summary

Thraustochytrid schizochytrium is one of the promising microalgae for omega-3 production. We evaluated the possibility of schizochytrium as omega-3 source comparing with other omega-3 sources that have been used before. The main results were the increased levels of DHA in the thigh meat of broilers fed SP, while EPA and DHA were on the rise in the meat of broilers fed SO, and ALA was increased in the meat of broilers fed FO. The ω-6/ω-3 ratio of the thigh meat improved in all treatments, approaching the guideline levels without adverse effects on the productive performance, carcass traits, and thigh meat quality. Hence, our results suggest that salmon oil, flaxseed oil, and schizochytrium could be used as omega-3 fatty acids sources to improve the omega-3 level and ω-6/ω-3 balance in broiler thigh meat and to allow consumers to easily enhance their intake of these vital nutrients for health benefits.

Abstract

Background: Looking for alternative omega-3 sources in broiler nutrition, microalgae began to get attention. We suspected that schizochytrium might play a similar role as other omega-3 sources that have been used before. Methods: 20 g/kg schizochytrium powder (SP), salmon oil (SO), and flaxseed oil (FO) in each of the three treatment groups were supplemented in the basal diet (CON), and productive performance, carcass traits, and thigh meat quality of broilers were evaluated. Results: There was a significantly higher weight gain in the SP treatment compared to the other groups, but no difference was found in feed intake and feed conversion ratio. Thiobarbituric acid reactive substance values increased during storage in all the treatments but were significantly lower for SP than for SO and FO after 7 days of storage. Among the ω-3 fatty acids (FAs), α-linolenic acid increased the most in the FO treatment, eicosapentaenoic acid increased the most in the SO treatment, and docosahexaenoic acid increased the most in the SP treatment in thigh meat, reflecting the FA composition of the lipid source diets. Conclusions: We suggested that all the dietary ω-3 FA sources could improve the FA composition of chicken meat and our results indicated the possibility to supplement broiler diets with 2% level of SP, SO, and FO as ω-3 FA sources to produce meat with a good nutritional quality for consumer’s health benefits.

Effects of dietary palm oil on broiler chicken productive performance and carcass characteristics: a comprehensive review

Palm oil is a natural energy source ingredient in poultry diets that offers a broad range of beneficial effects on the performance of broiler chickens. This review was conducted to highlight the impact of palm oil as a feed ingredient on growth performance and carcass quality, as well as the biochemical, antioxidant activity and tissue fatty acids (FA) composition of broiler chickens. Palm oil inclusion in broiler chickens' rations contributes significantly to the high metabolisable energy (ME) of feed formulation, increases feed palatability and decreases digesta passage rate in the intestine. The reviewed literature indicated that dietary palm oil has a beneficial effect on broiler chickens' overall growth performance traits. The addition of palm oil can also improve the heat tolerance of chickens reared in high ambient temperature conditions. Regardless of breed and breeding conditions, palm oil exhibits good oxidative stability in broiler chickens due to the presence of prevalent phytonutrient elements in this oil. The inclusion of palm oil increased palmitic (C_16:0) and oleic (C_18:1) acids in tissue deposits, which improves meat stability and quality. Moreover, molecular studies have revealed that higher mRNA expression of several lipid-related hepatic genes in broiler chickens fed palm oil. Nonetheless, dietary palm oil can influence FA deposition in tissues, modulate lipoprotein and triglycerides (TG) levels, and cytokine contents in the blood serum of broiler chickens.

Effect of dietary replacement of soybean meal with linseed meal on feed intake, growth performance and carcass quality of broilers

To increase the chicken's productivity and performance it is imperative to exploit underutilized oil crops such as linseed meal as protein source. This study evaluated the effect of replacing soybean meal with graded levels of linseed meal on feed intake, growth performance and carcass parameters of broiler chickens. A total of 180 day-old Cobb500 broilers were distributed to five treatment diets in a completely randomized design replicated three times with 12 chicks each. Isocaloric and isonitrogenous treatment diets formulated were T1 (0%, diet with no linseed meal), T2 (25%), T3 (50%), T4 (75%) and T5 (100%, soybean meal in the diet was replaced by linseed meal). The feeding experiment lasted for 44 days. The total feed intake, mortality rate and feed conversion ratio (FCR) during starter phase were similar (P > 0.05) among treatments. High (P < 0.05) starter phase body weight was recorded for T3 compared to T1, T2, T4 and T5 treatments but T2, T4 and T5 had similar average daily gain. The feed intake, body weight change, FCR and mortality during finisher phase and entire period were similar (P > 0.05) among treatment groups. The weight of most carcasses were similar (P > 0.05) among treatment except the weight of kidney, heart, breast, liver and abdominal fat. Kidney weight for T1 and T3 were higher (P < 0.05) than for T2, T4 and T5. The weight of heart for T3 was higher than T2 and T5 while T1, T3 and T4 were similar (P > 0.05). High (P < 0.05) breast weight were observed for T3 than T2 and T4. Liver weight for T3 was greater (P < 0.05) than T2 and T5. The total feed cost decreased with increasing levels of linseed meal. High net return was obtained from T3 followed by T4 and T2. The results showed that although linseed meal can replace 100% soybean meal in the ration without detrimental effect on the health, replacement at 50% (T3) is recommended for better performance of broilers.

Fighting Fat With Fat: n-3 Polyunsaturated Fatty Acids and Adipose Deposition in Broiler Chickens

Modern broiler chickens are incredibly efficient, but they accumulate more adipose tissue than is physiologically necessary due to inadvertent consequences of selection for rapid growth. Accumulation of excess adipose tissue wastes feed in birds raised for market, and it compromises well-being in broiler-breeders. Studies driven by the obesity epidemic in humans demonstrate that the fatty acid profile of the diet influences adipose tissue growth and metabolism in ways that can be manipulated to reduce fat accretion. Omega-3 polyunsaturated fatty acids (n-3 PUFA) can inhibit adipocyte differentiation, induce fatty acid oxidation, and enhance energy expenditure, all of which can counteract the accretion of excess adipose tissue. This mini-review summarizes efforts to counteract the tendency for fat accretion in broilers by enriching the diet in n-3 PUFA.

Enrichment of Broiler Chickens' Meat with Dietary Linseed Oil and Lysine Mixtures: Influence on Nutritional Value, Carcass Characteristics and Oxidative Stress Biomarkers

This study aimed to evaluate the effect of four combinations of dietary linseed oil and lysine mixtures on performance, fatty and amino acid profiles, oxidative stress biomarkers, cell energy and meat quality parameters of broiler chickens. One hundred and sixty broiler chicks were allocated into four groups. Birds of groups 1–4 were fed diets containing optimum lysine and 2% of linseed oil, optimum lysine and 4% of linseed oil, high lysine and 2% of linseed oil, and high lysine and 4% of linseed oil, respectively, for a period of 35 days. High linseed oil or lysine levels did not affect the performance of the tested birds, but the high level of dietary linseed oil decreased the concentrations of muscles’ saturated fatty acids (SFA). The highest values of ω-3 polyunsaturated fatty (ω-3 PUFA) and arachidonic acids with lowest levels of monounsaturated fatty (MUFA) were detected in the muscles of birds fed diets containing high linseed oils and/or lysine levels. High linseed oil or lysine levels provided the best essential amino acid profile and improved antioxidant components as well as cell energy, and tenderness and redness of the meat. Conclusively, high dietary lysine and linseed oil combinations improved the nutritional value, antioxidant status and cell energy of broiler chickens’ meat.

Soybean lecithin as an alternative energy source for grower and finisher broiler chickens: impact on performance, fatty acid digestibility, gut health, and abdominal fat saturation degree

An experiment was performed to assess the inclusion of soybean lecithin (SL) in the replacement of soybean oil (SO), for grower and finisher broiler chicken diets (up to 15 d of life), and its effects on performance, fatty acid (FA) absorption, gut health, and saturation degree of the abdominal fat pad (AFP). A total of 1,440 female Ross-308 chickens were distributed in 60 pens and were fed 5 experimental diets. The control diet (T1) was supplemented with SO (grower and finisher diets at 2.00%), and 4 levels of SL were included in replacement: T2 (0.25% in grower and 0.50% in finisher diets), T3 (0.50% in grower and 1.00% in finisher diets), T4 (0.75% in grower and 1.50% in finisher diets), and T5 (1.00% in grower and 2.00% in finisher diets). At day 39, titanium dioxide was added to finisher diets at 5 g/kg to perform a digestibility balance. At day 46, AFP, tissue, and gut digesta samples were collected to characterize FA digestibility, adipose saturation degree, microbial groups, and histomorphometry. No effects were associated with SO replacement by SL on performance (P > 0.05), ileal digestibility of total, saturated and monounsaturated FA (P > 0.05), nor jejunal morphology (P > 0.05). Total replacement of SO by SL reduced ileal absorption of polyunsaturated FA (P < 0.02) and increased jejunal Lactobacillus spp. counts (P = 0.049). Higher levels of SL inclusion (T4 and T5) lowered polyunsaturated FA concentration of the AFP (P = 0.002) and, thus, slightly reduced its unsaturated-to-saturated FA ratio (P = 0.005). Soybean lecithin inclusion did not modify performance parameters, total FA absorption, nor jejunal morphology, however caused changes on polyunsaturated FA absorption, jejunal microbiota, and saturation degree of the AFP. The study demonstrates that soybean lecithin can be included, in combination with or in replacement of soybean oil, as an alternative energy source for grower (up to a 1%) and finisher broiler diets (up to 2%).

Effects of dietary incorporation of linseed oil with soybean isoflavone on fatty acid profiles and lipid metabolism-related gene expression in breast muscle of chickens

The meat quality of chicken is an important factor affecting the consumer's health. It was hypothesized that n-3 polyunsaturated fatty acid (n-3 PUFA) could be effectively deposited in chicken, by incorporating antioxidation of soybean isoflavone (SI), which led to improved quality of chicken meat for good health of human beings. Effects of partial or complete dietary substitution of lard (LA) with linseed oil (LO), with or without SI on growth performance, biochemical indicators, meat quality, fatty acid profiles, lipid-related health indicators and gene expression of breast muscle were examined in chickens. A total of 900 males were fed a corn-soybean meal diet supplemented with 4% LA, 2% LA + 2% LO and 4% LO and the latter two including 30 mg SI/kg (2% LA + 2% LO + SI and 4% LO + SI) from 29 to 66 days of age; each of the five dietary treatments included six replicates of 30 birds. Compared with the 4% LA diet, dietary 4% LO significantly increased the feed efficiency and had no negative effect on objective indices related to meat quality; LO significantly decreased plasma triglycerides and total cholesterol (TCH); abdominal fat percentage was significantly decreased in birds fed the 4% LO and 4% LO + SI diets. Chickens with LO diets resulted in higher contents of α-linolenic acid (C18:3n-3), EPA (C20:5n-3) and total n-3 PUFA, together with a lower content of palmitic acid (C16:0), lignoceric acid (C24:0), saturated fatty acids and n-6:n-3 ratio in breast muscle compared to 4% LA diet (P < 0.05); they also significantly decreased atherogenic index, thrombogenic index and increased the hypocholesterolemic to hypercholesterolemic ratio. Adding SI to the LO diets enhanced the contents of EPA and DHA (C22:6n-3), plasma total superoxide dismutase, reduced glutathione (GSH)/oxidized glutathione and muscle GSH content, while decreased plasma total triglyceride and TCH and malondialdehyde content in plasma and breast muscle compared to its absence (P < 0.05). Expression in breast muscle of fatty acid desaturase 1 (FADS1), FADS2, elongase 2 (ELOVL2) and ELOVL5 genes were significantly higher with the LO diets including SI than with the 4% LA diet. Significant interactions existed between LO level and inclusion of SI on EPA and TCH contents. These findings indicate that diet supplemented with LO combined with SI is an effective alternative when optimizing the nutritional value of chicken meat for human consumers.

Low Dietary n-6/n-3 PUFA Ratio Regulates Meat Quality, Reduces Triglyceride Content, and Improves Fatty Acid Composition of Meat in Heigai Pigs

The objective of this study was to investigate the effects of dietary supplementation with different n-6/n-3 polyunsaturated fatty acid (PUFA) ratios on growth performance, meat quality, and fatty acid profile in Heigai pigs. A total of 54 Heigai finishing pigs (body weight: 71.59 ± 2.16 kg) were randomly divided into three treatments with six replications (three pigs per replication) and fed diets containing different n-6/n-3 PUFA ratios: 8:1, 5:1, and 3:1. Pigs fed the dietary n-6/n-3 PUFA ratio of 8:1 had the highest feed to gain ratio (p < 0.01), carcass weight (p < 0.05), redness a* (p < 0.01), and yellowness b* (p < 0.01). Fatty acid compositions in longissimus dorsi muscle (LDM) and subcutaneous adipose tissue (SAT) were significantly changed (p < 0.01). Notably, the meat from the pigs fed with the low dietary n-6/n-3 PUFA ratio had higher n-3 PUFA contents (p < 0.01) and lower n-6/n-3 PUFA ratio (p < 0.01). The triglyceride and total cholesterol contents were significantly decreased in SAT from the pigs fed with dietary n-6/n-3 PUFA ratios of 5:1 (p < 0.05) and 3:1 (p < 0.01). Reducing n-6/n-3 PUFA ratio upregulated the expression of HSL (p < 0.05), CPT1 (p < 0.01), and FABP4 (p < 0.01) but downregulated ATGL (p < 0.01) expression. These results demonstrate that the lower n-6/n-3 PUFA ratio regulates meat quality and enhances the deposition of n-3 PUFA in Heigai pigs.

Effects of replacing soybean meal with perilla seed meal on growth performance, and meat quality of broilers

The purpose of this study was to evaluate effects of replacing soybean meal with perilla seed meal (PSM) on growth performance, proximate composition of meat, meat quality, and fatty acids composition of meat in broilers. A total of 60 one-day-old chicks of ROSS 308 (initial body weight of 44.8 ± 0.4 g) were randomly allotted to four treatment groups (15 replicate cages with 1 broilers per cage) in a period of 5 weeks. Dietary treatments included control (CON) basal diet (corn-soybean meal-based diets) and test diets in which PSM was included at 0.5% (T1), 1% (T2), or 2% (T3) to gradually replace soybean meal. At the end of experiment, all broilers were slaughtered for collecting breast and thigh meat. At 5 weeks, T2 and T3 treatment groups had higher (p < 0.05) body weights than CON and T1 treatment groups. Weight gain was increased (p < 0.05) in T2 and T3 treatment groups. Feed intake was decreased (p < 0.05) in T3 treatment group. Broilers in T2 treatment group had lower (p < 0.05) feed conversion ratio than those in other treatment groups. In proximate composition of breast meat, there was no significant (p > 0.05) difference in moisture and ash. Fat composition of breast meat was significantly (p < 0.05) increased in T2 and T3 treatment groups. Regarding meat quality, broilers fed T3 diet had higher (p < 0.05) water holding capacity than those fed other diets. Regarding fatty acids composition of thigh meat, broilers fed T3 diet had higher (p < 0.05) linolenic acid than those fed other diets. In conclusion, soybean meal replaced by 2% perilla seed meal in broiler diet can improve growth performance, meat quality, and fatty acids composition of thigh meat in broilers. Perilla seed meal can be a lot of potential alternatives feedstuff for soybean meal in this study.

Comparison of mathematical and comparative slaughter methodologies for determination of heat production and energy retention in broilers

Understanding factors affecting ME availability for productive processes is an important step in optimal feed formulation. This study compared a modelling methodology with the comparative slaughter technique (CST) to estimate energy partitioning to heat production and energy retention (RE) and to investigate differences in heat dissipation. At hatch, 50 broilers were randomly allocated in one of 4 pens equipped with a precision feeding station. From day 14 to day 45, they were either fed with a low-ME (3,111 kcal/kg ME) or a high-ME (3,383 kcal/kg ME) diet. At day 19, birds were assigned to pair-feeding in groups of 6 with lead birds eating ad libitum (100%) and follow birds eating at either 50, 60, 70, 80, or 90% of the paired lead's cumulative feed intake. Heat production and RE were estimated by CST and with a nonlinear mixed model explaining daily ME intake (MEI) as a function of metabolic BW and average daily gain (ADG). The energy partitioning model predicted MEI = (145.10 + u) BW^0.83 + 1.09 × BW^−0.18 × ADG^1.19 + ε. The model underestimated heat production by 13.4% and overestimated RE by 22.8% compared with the CST. The model was not able to distinguish between net energy for gain values of the diets (1,448 ± 18.5 kcal/kg vs. 1,493 ± 18.0 kcal/kg for the low-ME and high-ME diet, respectively), whereas the CST found a 148 kcal/kg difference between the low-ME and high-ME diets (1,101 ± 22.5 kcal/kg vs. 1,249 ± 22.0 kcal/kg, respectively). The estimates of the net energy for gain values of the 2 diets decreased with increasing feed restriction. The heat increment of feeding did not differ between birds fed with the low- or high-ME diet (26% of MEI). Additional measurements on heat dissipation, physical activity, and immune status indicated that the energetic content of the diet and feed restriction affect some parameters (shank temperature, feeding station visits) but not others (leukocyte counts, heterophil to lymphocyte ratio, and immune cell function).

Effects of dietary perilla seed oil supplementation on lipid metabolism, meat quality, and fatty acid profiles in Yellow-feathered chickens

This study evaluated the effect of the dietary replacement of 1% lard (CT) with 1% perilla oil (PO), 0.9% perilla oil + 0.1% anise oil (PA), or 0.9% perilla oil + 0.1% ginger oil (PG) on indices of lipid metabolism, antioxidant capacity, meat quality, and fatty acid profiles from Yellow-feathered chickens at day 63. Compared with the CT chickens, those given perilla oil had decreased (P < 0.05) plasma lipid levels including triglycerides (TG), total cholesterol (TCH), and low-density lipoprotein cholesterol (LDL-C). Hepatic TG, TCH levels, and fatty acid synthase activity were also decreased (P < 0.05) in chickens fed diets containing perilla oil. Abdominal fat percentage was significantly decreased in birds fed the PG compared to CT diets. Birds fed the PA or PG diets had increased (P < 0.05) hepatic total SOD, glutathione peroxidase, and glutathione-S-transferase than in chickens given PO alone. In addition, the content of reduced glutathione (GSH) in breast muscle was lower (P < 0.05) in birds fed PO compared with those given PG, and the reverse was true for content of malondialdehyde. Compared with the CT diet, the PO diet decreased breast muscle shear values and increased yellowness (b*) of breast muscle (P < 0.05). Birds fed the PA or PG diets had meat with better overall acceptability than those fed the CT diet. Chickens fed perilla oil diets exhibited higher contents of α-linolenic acid (C18:3n-3), DHA (22:6n-3), polyunsaturated fatty acids, and n-3 fatty acids, together with a lower content of myristic acid (C14:0), palmitic acid (C16:0), stearic acid (C18:0), total saturated fatty acids, and n-6/n-3 ratio compared to controls (P < 0.05). These findings indicate that perilla oil has the potential to decrease lipid-related indices and improve fatty acid profiles of breast meat in chickens without adverse effect on antioxidant status or meat quality; this was even better when perilla oil was given together with anise oil or ginger oil.

Effects of dietary lipid sources on growth performance and carcass traits in Pekin ducks

This study was conducted to determine the influence of dietary lipid sources on growth performance, carcass traits and taste scores in Pekin ducks. A total of 1,500 fifteen-day-old ducks (820 ± 22 g) were blocked based on body weight (BW), and randomly allotted to 3 treatments with 10 replicates of 50 birds each (25 males and 25 females). The experiment lasted for 4 wk, and dietary treatments included 3 different lipid sources (soybean oil, duck fat, and palm oil), which were evaluated in corn-soybean meal diets (3250 kcal/kg metabolizable energy and 16.5% crude protein for grower diet and 3350 kcal/kg metabolizable energy and 15.5% crude protein for finisher diet). During days 15 to 28, feeding soybean oil and palm oil diets increased (P < 0.05) body weight gain (BWG), but decreased (P < 0.05) feed intake, feed-to-gain ratio (F/G) and caloric conversion compared with duck fat. During days 29 to 42, birds fed duck fat diet had higher BWG, but lower (P < 0.05) F/G and caloric conversion than those fed soybean oil and palm oil diets. Overall, feeding soybean oil diet increased (P < 0.05) BWG and final BW, but decreased (P < 0.05) F/G compared with palm oil. Birds fed duck fat diet had higher (P < 0.05) skin, subcutaneous fat and abdominal fat yield compared with palm oil. Left breast meat yield in soybean oil group was higher (P < 0.05) than that in duck fat and palm oil groups. Birds in soybean oil group had lower (P < 0.05) roasting loss, but higher (P < 0.05) comprehensive score compared with duck fat and palm oil. In summary, birds fed soybean oil diet had the best growth performance and taste scores for roasting, whereas the duck fat was better in abdominal fat and subcutaneous fat yield than soybean oil and palm oil in Pekin ducks from 15 to 42 d of age under the same nutritional level.

Effects of dietary energy and protein content and lipid source on growth performance and carcass traits in Pekin ducks

The present study was conducted to determine the impact of dietary energy and protein concentrations and lipid sources on growth performance and carcass traits of Pekin ducks. In Exp. 1, 15-day-old ducks (6 replicate pens, 60 ducks/pen) were randomly assigned to 4 dietary treatments with different metabolizable energy (ME) and crude protein (CP) concentrations (2,850 kcal/kg and 16%, 2,950 kcal/kg and 16.5%, 3,050 kcal/kg and 17.0%, and 3,150 kcal/kg and 17.5%) based on body weight (BW). In Exp. 2, 20-day-old ducks (4 replicate pens, 60 ducks/pen) were randomly allotted to 3 dietary fat sources (soybean oil, lard, and palm oil) with or without emulsifier in a 3 × 2 factorial arrangement. In Exp. 1, increasing ME and CP level improved (P < 0.05) body weight gain (BWG) and cost-to-gain ratio linearly, but reduced (P < 0.05) feed intake (FI) and feed-to-gain ratio (F/G) linearly. Breast skin thickness and liver redness (a*) value increased (P < 0.05) linearly with the increasing ME and CP level. In Exp. 2, no interactions between fat sources and emulsifier were observed. Feeding lard and palm oil diets increased (P < 0.05) final BW and BWG compared to soybean oil. Birds fed soybean oil and palm oil diets had lower (P < 0.05) FI compared to those fed lard diet. F/G in soybean oil and lard groups was higher (P < 0.05) compared to palm oil group. Birds in palm oil and lard groups had higher (P < 0.05) European production efficiency factor than those in soybean oil group. The addition of emulsifier increased (P < 0.05) BWG. In summary, the optimal ME and CP level for roasting was 2,950 kcal/kg ME and 16.5% CP and the palm oil was better than soybean oil and lard in Pekin ducks from 15 to 40 D of age.

Evaluating Impacts of Different Omega-6 to Omega-3 Fatty Acid Ratios in Corn-Soybean Meal-Based Diet on Growth Performance, Nutrient Digestibility, Blood Profiles, Fecal Microbial, and Gas Emission in Growing Pigs

Simple Summary

There are two major classes of polyunsaturated fatty acids found in the diet, omega-3 and omega-6, these polyunsaturated fatty acids are essential because they cannot be synthesized by humans and animals. Also, they cannot be converted into each other in the body. Supplementation of omega-3 has been reported to improve the performance and health of pigs. However, during the past years, studies had demonstrated that animal performance could be influenced by the dietary level or the ratio of omega-6 and omega-3. A high omega-6: omega-3 ratio in diets promotes the pathogenesis of many diseases, including cardiovascular disease, cancer, and inflammatory and autoimmune diseases. An optimal omega-6: omega-3 ratio could inhibit immune stimulation to ensure the availability of more energy and nutrients for high performance and the homeostatic pathway. The present study investigated the effects of different omega-6: omega-3 ratios (17:1, 15:1, 10:1, 5:1) on growth performance, nutrient digestibility, blood profiles, fecal microflora, and gas emission in growing pigs. The results of this study showed that reducing omega-6: omega-3 ratio from 17:1 to 5:1 by increasing omega-3 in the diet increased body weight, energy digestibility, and reduced the low-density lipoprotein concentrations of blood in growing pigs.

Abstract

This study was conducted to evaluate the effect of different omega-6: omega-3 fatty acid (FA) ratios in a corn–soybean meal-based diet in growing pigs. A total of 140 [Duroc × (Landrace × Yorkshire)] growing pigs with an average body weight (BW) of 24.75 ± 1.43 kg were used in a 6-week trial. Pigs were allocated randomly into one of four treatments according to sex and BW (seven replications with five pigs per pen). The treatment groups consisted of 4 diets with omega-6:omega-3 FA ratios of 17:1, 15:1, 10:1, and 5:1. In the current study, the energy digestibility, BW, and average daily gain (ADG) increased (p < 0.05) in pigs provided with the 5:1 diet compared to pigs fed the 17:1 diet in the sixth week. The low-density lipoprotein (LDL) concentrations of blood were lower (p < 0.05) in pigs fed the 5:1 diet compared to the 17:1 and 15:1 diet. However, the fecal microflora and fecal gas emissions were unaffected (p > 0.05) by the different omega-6: omega-3 FA ratios in diets. In conclusion, reducing omega-6: omega-3 ratio by increasing omega-3 in diet improved BW, ADG, and gross energy digestibility, and reduced the LDL concentrations of blood in growing pigs.

Crude soybean lecithin as alternative energy source for broiler chicken diets

Two experiments were conducted to evaluate the use of crude soybean lecithin (L) as an alternative energy source in broiler feeding and to study its influence on performance, fatty acid (FA) digestibility between 9 to 11 D and 36 to 37 D, feed AME content, and the FA profile of the abdominal fat pad (AFP). A basal diet was supplemented at 3% with soybean oil (S; experiment 1) or a monounsaturated vegetable acid oil (A; experiment 2) and increasing amounts of L (1, 2, and 3%) were included in replacement. The inclusion of L did not modify performance results (P > 0.05). In starter diets, the replacement of S by L reduced feed AME content (P < 0.001) and lowered PUFA digestibility (P = 0.028), whereas in the grower-finisher phase, a blend of 2% of S and 1% of L did not modify feed AME content or FA digestibility. When L was included instead of A, no effects on feed AME value and total FA digestibility (P > 0.05) were shown in the starter phase, whereas in grower-finisher diets, a blending of 2% of A and 1% of L enhanced feed AME content (P < 0.001) and total FA digestibility (P = 0.001). The FA profile of the AFP reflected the FA composition of the diets. Crude soybean lecithin represents an alternative energy source for broiler chickens, and it can be used in growing-finishing diets in replacement of 1% S. The best option to include both alternative fats (L and A) was 2% of L with 1% of A in starter diets and 1% of L with 2% of A in grower-finisher diets because they showed positive synergic effects. The results suggest that dietary FA profile have a bigger impact on the AFP saturation degree than the different dietary lipid molecular structures.

Soybean Lecithin High in Free Fatty Acids for Broiler Chicken Diets: Impact on Performance, Fatty Acid Digestibility and Saturation Degree of Adipose Tissue

Simple Summary

The search of alternatives for soybean oil, as a dietary energy source, has generated a lot of interest in broiler feeding due to economic and supply reasons. Soybean lecithin, as a co-product derived from the soybean oil degumming process, and its blending with other by-products derived from the vegetable oil refining process such as acid oils, may represent an alternative energy source for broiler chicken diets formulation. The current study has demonstrated that soybean lecithin high in free fatty acids can be included in grower–finisher diets, as a partial replacer of soybean oil or in combination with an acid oil, without impairing performance or fatty acid digestibility and causing minor changes in the fatty acid composition of the abdominal fat pad.

Abstract

Two experiments were conducted to evaluate the inclusion of soybean lecithin with a high free fatty acid content (L) in starter and grower–finisher broiler diets, as well as its influence on performance, energy and fatty acid (FA) utilization and the FA profile of the abdominal fat pad (AFP). A basal diet was supplemented with soybean oil (S; Experiment 1) or acid oil (AO; Experiment 2) at 3%, and increasing amounts of L (1%, 2% and 3%) were included in replacement. The inclusion of L did not modify performance parameters (p > 0.05). The S replacement by L reduced energy and total FA utilization (p ≤ 0.05) in starter diets; however, in grower–finisher diets, a replacement up to 2% did not modify energy and FA utilization (p > 0.05). The AO substitution by L produced no modifications on energy and FA utilization (p > 0.05) during the starter phase, while the blend of 1% of AO and 2% of L resulted in the best combination in terms of the FA digestibility. The FA profile of the AFP reflected the FA composition of diets. The addition of L could replace, up to 2% or be blended with AO in broiler grower–finisher diets as an energy source.

The Effect of Dietary Camelina sativa Oil or Cake in the Diets of Broiler Chickens on Growth Performance, Fatty Acid Profile, and Sensory Quality of Meat

The aim of the present study was to determine the effect of supplementing the diets of broiler chickens with Camelina sativa oil or cake as a source of polyunsaturated fatty acids (PUFAs) on their growth performance, fatty acid profile, and sensory quality of meat. The 456 Ross 308 broilers aged 21-42 days were divided into 3 groups with 4 replicates of 38 birds in each. Chickens in the control group I (CTR) were fed a standard grower-finisher feed mixture containing 60 g/kg rapeseed oil. The experimental components, C. sativa oil-CSO (group II) or cake-CSC (group III), were included in a diet based on wheat and soybean at 40 and 100 g/kg, respectively. The use of Camelina oil and cake as feed components did not have a significant effect on the growth performance of the chickens. Analysis of the fatty acid profile in the lipids of the breast muscles showed that Camelina oil and cake reduced the content of monounsaturated fatty acids (p < 0.05) but increased the content of n-3 polyunsaturated fatty acids, especially α-linolenic acid (C18:3) (p < 0.01). Furthermore, both components reduced the ratio of n-6/n-3 PUFAs in the breast muscles (p < 0.01). Sensory analysis revealed that Camelina oil had a beneficial effect on meat juiciness, whereas Camelina cake slightly worsened the flavor and tastiness of the meat. In conclusion, supplementing the diet of broiler chickens with Camelina oil or cake can be an efficient method for modifying the fatty acid profile of the meat lipids in a beneficial way, without any negative impact on the growth performance of the chickens. According to the dietetic recommendations for humans, broiler chicken meat with a higher level of PUFA n-3 can be a good alternative source of these fatty acids in the human diet. Furthermore, Camelina oil improved the juiciness of breast meat.

Omega-3 and Omega-6 Fatty Acids in Poultry Nutrition: Effect on Production Performance and Health

Omega-3 (ω-3) and omega-6 (ω-6) fatty acids are important components of cell membranes. They are essential for health and normal physiological functioning of humans. Not all fatty acids can be produced endogenously owing to the absence of certain desaturases; however, they are required in a ratio that is not naturally achieved by the standard diet of industrialized nations. Poultry products have become the primary source of long-chain polyunsaturated fatty acids (LC-PUFA), with one of the most effective solutions being to increase the accretion of PUFAs in chicken products via the adjustment of fatty acids in poultry diets. Several studies have reported the favorable effects of ω-3 PUFA on bone strength, bone mineral content and density, and semen quality. However, other studies concluded negative effects of LC-PUFA on meat quality and palatability, and acceptability by consumers. The present review discussed the practical application of ω-3 and ω-6 fatty acids in poultry diets, and studied the critical effects of these fatty acids on productive performance, blood biochemistry, immunity, carcass traits, bone traits, egg and meat quality, and semen quality in poultry. Future studies are required to determine how poultry products can be produced with higher contents of PUFAs and favorable fatty acid composition, at low cost and without negative effects on palatability and quality.

A genome-wide association study reveals novel genomic regions and positional candidate genes for fat deposition in broiler chickens

Background

Excess fat content in chickens has a negative impact on poultry production. The discovery of QTL associated with fat deposition in the carcass allows the identification of positional candidate genes (PCGs) that might regulate fat deposition and be useful for selection against excess fat content in chicken’s carcass. This study aimed to estimate genomic heritability coefficients and to identify QTLs and PCGs for abdominal fat (ABF) and skin (SKIN) traits in a broiler chicken population, originated from the White Plymouth Rock and White Cornish breeds.

Results

ABF and SKIN are moderately heritable traits in our broiler population with estimates ranging from 0.23 to 0.33. Using a high density SNP panel (355,027 informative SNPs), we detected nine unique QTLs that were associated with these fat traits. Among these, four QTL were novel, while five have been previously reported in the literature. Thirteen PCGs were identified that might regulate fat deposition in these QTL regions: JDP2, PLCG1, HNF4A, FITM2, ADIPOR1, PTPN11, MVK, APOA1, APOA4, APOA5, ENSGALG00000000477, ENSGALG00000000483, and ENSGALG00000005043. We used sequence information from founder animals to detect 4843 SNPs in the 13 PCGs. Among those, two were classified as potentially deleterious and two as high impact SNPs.

Conclusions

This study generated novel results that can contribute to a better understanding of fat deposition in chickens. The use of high density array of SNPs increases genome coverage and improves QTL resolution than would have been achieved with low density. The identified PCGs were involved in many biological processes that regulate lipid storage. The SNPs identified in the PCGs, especially those predicted as potentially deleterious and high impact, may affect fat deposition. Validation should be undertaken before using these SNPs for selection against carcass fat accumulation and to improve feed efficiency in broiler chicken production.

Electronic supplementary material

The online version of this article (10.1186/s12864-018-4779-6) contains supplementary material, which is available to authorized users.

Factors affecting adipose tissue development in chickens: A review

The intense genetic selection for rapid growth in broilers has resulted in an increase in voluntary feed intake and growth rate, accompanied by increased fat deposition in adipose tissue depots throughout the body. Adipose tissue expansion is a result of the formation of adipocytes (several processes collectively referred to as adipogenesis) and cellular accumulation of triacylglycerols inside lipid droplets. In mammals, different anatomical depots are metabolically distinct. The molecular and cellular mechanisms underlying adipose tissue development have been characterized in mammalian models, whereas information in avian species is scarce. The purpose of this review is to describe factors regulating adipogenesis in chickens, with an emphasis on dietary factors and the broiler. Results from many studies have demonstrated effects of dietary nutrient composition on adipose tissue development and lipid metabolism. Transcription factors, such as peroxisome proliferator-activated receptor γ, CCAAT/enhancer-binding proteins α and β, and sterol regulatory element binding proteins orchestrate a series of cellular events that lead to an increase in activity of fatty acid transport proteins and enzymes that are responsible for triacylglycerol synthesis. Understanding the mechanisms underlying adipose tissue development may provide a practical strategy to affect body composition of the commercial broiler while providing insights on diets that maximize conversion into muscle rather than fat and affect depot-dependent deposition of lipids. Because of the propensity to overeat and become obese, the broiler chicken also represents an attractive biomedical model for eating disorders and obesity in humans.

Effects of dietary supplementation with a combination of plant oils on performance, meat quality and fatty acid deposition of broilers

Objective

This study was to evaluate effects of mixed plant oils (identified as mixed oil 1 [MO1] and mixed oil 2 [MO2]) on performance, serum composition, viscera percentages, meat quality, and fatty acid deposition of broilers.

Methods

A total of 126 one-day-old Arbor Acres male broiler chicks (weighing 44.91± 0.92 g) were randomly allocated to 1 of 3 treatments with 7 replicate pens per treatment (6 broilers per pen). Dietary treatments included a corn-soybean basal diet supplemented with 3% soybean oil (CTR), basal diet with 3% MO1 (a mixture of 15% corn oil, 10% coconut oil, 15% linseed oil, 20% palm oil, 15% peanut oil and 25% soybean oil; MO1), or basal diet with 3% MO2 (a combination of 50% MO1 and 50% extruded corn; MO2). The trial consisted of phase 1 (d 1 to 21) and phase 2 (d 22 to 42).

Results

Compared to CTR, broilers fed MO (MO1 or MO2) had greater (p<0.05) average daily gain in phase 1, 2, and overall (d 1 to 42), redness in thigh muscle, concentrations of serum glucose, serum albumin, saturated fatty acids (SFA) and n-6/n-3 polyunsaturated fatty acids (PUFA) ratio in breast muscle, while these broilers also showed lower (p≤0.05) drip loss and concentrations of C18:3n-3 and PUFA/SFA ratio in breast muscle. Broilers fed MO2 had higher (p<0.05) liver percentage, while broilers fed MO1 had lower (p≤0.05) feed conversion ratio in phase 1 and increased (p<0.05) contents of C18:2n-6, C20:5n-3, C22:6n-3, and n-3 PUFA in breast muscle compared to CTR.

Conclusion

Mixed plant oils had positive effects on performance, serum parameters, meat quality, liver percentage and fatty acid deposition in broilers, which indicates they can be used as better dietary energy feedstocks than soybean oil alone.

Effects of dietary fat source and supplemental lysophosphatidylcholine on performance, immune responses, and ileal nutrient digestibility in broilers fed corn/soybean meal- or corn/wheat/soybean meal-based diets

Two separate experiments were conducted to investigate the effect of different fat sources and a supplemental exogenous emulsifier (lysophosphatidylcholine, LPC) on growth performance, antibody production titers, and ileal nutrient digestibility in broiler chicks fed with different basal diets. A total of 288 one-day-old Ross 308 chicks were used for each trial (6 dietary treatments based on 3 × 2 factorial arrangements of treatments in both trials) with 4 replicates of 12 birds each. Dietary treatments consisted of 3 different fat sources (soy oil, SO; soy free fatty acids, SFFA; and palm fat powder, PFP) and 2 LPC levels (0 and 0.1% of diet), which were evaluated with 2 different basal diets (corn/soybean meal-based diets in Exp. 1, or corn/wheat/soybean meal-based diets in Exp. 2). In Exp. 1, average daily feed intake (ADFI) was increased (P < 0.01) in birds fed PFP diets compared with those fed SO or SFFA diets. Although supplemental LPC decreased (P < 0.01) ADFI, the birds fed SFFA diets had the greater ADFI at the presence of LPC (fat source × LPC, P < 0.01). Dietary supplementation of LPC caused a 4.6% improvement (P < 0.001) in average daily weight gain (ADWG) and consequently improved (P < 0.01) feed conversion ratio (FCR). Supplemental LPC was more effective in increasing ADWG in SFFA-containing diets, resulted in a significant (P < 0.01) dietary fat source × LPC interaction. Dietary inclusion of LPC increased (P < 0.01) bursa weight and improved (P < 0.05) antibody production titers against sheep red blood cells and Newcastle disease virus during primary responses. Ileal digestibility of ether extract (EE) was improved (P < 0.05) in birds fed diets containing SO as compared with those fed PFP diets; dietary LPC supplementation, however, had no marked effect on ileal nutrient digestibility. In Exp. 2, ADWG was greater (P < 0.05) in birds fed SO-containing diets compared with PFP-supplemented broiler chicks. Furthermore, dietary supplementation with LPC improved (P < 0.05) FCR value by 2.1%. Relative thymus weight was greater (P < 0.05) in birds fed LPC-supplemented diets than those fed unsupplemented diets. Supplemental LPC increased (P < 0.05) Gumboro antibody titer, and the lowest antibody response was allotted to the birds fed PFP diets. The greatest (P < 0.05) EE digestibility was assigned to the birds fed SO and SFFA diets. The present findings showed that birds fed SFFA-containing diets had similar performance as SO birds, and supplemental LPC improved overall performance especially in SFFA-fed birds.

Dietary Conjugated Linoleic Acid Supplementation Leads to Downregulation of PPAR Transcription in Broiler Chickens and Reduction of Adipocyte Cellularity

Conjugated linoleic acids (CLA) act as an important ligand for nuclear receptors in adipogenesis and fat deposition in mammals and avian species. This study aimed to determine whether similar effects are plausible on avian abdominal fat adipocyte size, as well as abdominal adipogenic transcriptional level. CLA was supplemented at different levels, namely, (i) basal diet without CLA (5% palm oil) (CON), (ii) basal diet with 2.5% CLA and 2.5% palm oil (LCLA), and (iii) basal diet with 5% CLA (HCLA).The content of cis-9, trans-11 CLA was between 1.69- and 2.3-fold greater (P < 0.05) than that of trans-10, cis-12 CLA in the abdominal fat of the LCLA and HCLA group. The adipogenic capacity of the abdominal fat depot in LCLA and HCLA fed chicken is associated with a decreased proportion of adipose cells and monounsaturated fatty acids (MUFA). The transcriptional level of adipocyte protein (aP2) and peroxisome proliferator-activated receptor gamma (PPARγ) was downregulated by 1.08- to 2.5-fold in CLA supplemented diets, respectively. It was speculated that feeding CLA to broiler chickens reduced adipocyte size and downregulated PPARγ and aP2 that control adipocyte cellularity. Elevation of CLA isomers into their adipose tissue provides a potential CLA-rich source for human consumption.

Influence of dietary fat source on growth performance responses and carcass traits of broiler chicks

This study was conducted to determine the effects of three different fat sources and their combination on growth performance, carcass traits and intestinal measurements of broiler chickens reared to 42 d of age. Two hundred day-old male broiler chicks (Ross 308) were randomly assigned to one of five treatments with four replicates of 10 chicks based on a completely randomized design. The dietary treatments consisted of 4% added fat from three different sources and their combination as follows: T, diet containing 4% tallow; CO, diet containing 4% canola oil; SFO, diet containing 4% sunflower oil; TCO, diet containing 2% tallow+2% canola oil; TSFO, diet containing 2% tallow+2% sunflower oil. Dietary fat type affected significantly BW and gain as well as feed efficiency in birds fed the TCO diets compared with those fed the other diets. Dietary fat type also modified meat yield, resulting in a higher breast and drumstick yields in the birds fed TCO and TSFO diets, respectively. Most of internal organ relative weights and small intestine measurements were not influenced by dietary treatments, except for the abdominal fat pad weight that was lower in birds fed SFO and for small intestinal length that was influenced by fat source. Results from the current study suggested that the supplementation with a combination of vegetable and animal fat sources in broiler diet supported positively growth performance and carcass parameters.

Effects of a dietary antioxidant blend and vitamin E on growth performance, oxidative status, and meat quality in broiler chickens fed a diet high in oxidants

The aim of the study was to determine the effects of a dietary antioxidant blend (AB) and vitamin E on performance, oxidative status, and meat quality. Cobb 500 male broilers (n = 1,200, d 0) were randomly distributed into 6 treatments with 10 replicate pens. Treatments included 1) HO: high oxidant diet, vitamin E at 10 IU/kg, 3% oxidized soybean oil, 3% polyunsaturated fatty acid (PUFA) source; 2) VE: the HO diet with vitamin E at 200 IU/kg; 3) AOX: the HO diet with AB at 135 mg/kg; 4) VE+AOX: the HO diet with vitamin E at 200 IU/kg and AB at 135 mg/kg; 5) SC: standard control; and 6) PC: positive control, the SC diet with AB at 135 mg/kg. From d 0 through d 21, high oxidant diet treatment birds had greater BW, ADG, and ADFI than the SC birds; the AOX birds had better G:F on d 10 and 42, and from d 0 to 42 than SC birds (P < 0.05). The plasma TBA reactive substance level was lower in the AOX birds than the VE treatment birds in all phases (P < 0.05). High oxidant diet treatment birds had greater α-1-acid glycoprotein levels on d 10 than SC and PC birds (P < 0.05). The AOX, PC, and SC birds had a greater level of uric acid than the HO and VE+AOX birds on d 10. Superoxide dismutase expression in the liver was less with the HO treatment compared with the SC treatment on d 7 (P < 0.05). The vitamin E concentration in the breast muscle was greatest in the VE birds, whereas vitamin A concentration was greater in the PC birds compared with the SC birds on d 21 (P < 0.05). Compared with VE and AOX, the HO treatment had greater drip loss (P < 0.05). In conclusion, dietary addition of AOX was effective in improving growth, moderately restored the whole body antioxidant capability, and reduced drip loss.

Effects of linseed oil and palm oil on growth performance, tibia fatty acid and biomarkers of bone metabolism in broilers

1. This study was conducted to determine the effects of different dietary fat sources on growth performance, tibia fatty acids and biomarkers of bone metabolism in broilers. 2. One-d-old commercial Arbor Acres broilers were fed with a maize-soya bean basal diet for 42 d, supplemented with oils according to the following 5 treatments: lard (lard group); linseed oil (linseed oil group); palm oil (palm oil group); linseed oil + palm oil (60:40 or 40:60 w/w, LP-1 group and LP-2 group, respectively). 3. No significant differences in weight gain, feed intake and gain/feed ratio were observed between the lard and linseed oil groups. Birds fed on palm oil had significantly greater weight gain and feed intake than those fed on lard or linseed oil. Growth performance in LP-1 and LP-2 was significantly greater than that of single-oil groups. 4. Tibia growth and bone characteristics were not influenced by supplementation with lard, linseed oil, or palm oil alone, but broilers fed on a mixture of fats had significantly greater tibia weight and length compared to broilers fed on linseed oil. Bone mineral density in tibia was significantly increased in LP-1 and LP-2 groups. 5. Supplementation of linseed oil alone or in combination with palm oil enhanced apparent digestibility of calcium, reduced serum calcium and increased tibia calcium concentrations. Moreover, supplementation with linseed oil alone or in combination with palm oil had a positive effect on biomarkers of bone growth. 6. The combination of linseed and palm oils was beneficial for growth performance, tibia growth and biomarkers of bone metabolism.

Effect of lipid sources and inclusion levels in diets for broiler chickens

This research aimed to evaluate the interactions and effects of 2 and 4% addition levels of poultry slaughterhouse fat (chicken tallow) and soybean oil in diets for broiler chickens. Two experiments were carried out using one-day-old male Cobb chicks in an entirely random design with a 2x2 factorial scheme. In the first experiment, 560 chicks were used to evaluate performance and carcass characteristics. In the second experiment, 100 chicks were used to determine the nutrient digestibility, dietary energy utilization and the lipase and amylase pancreatic activity. There was no interaction between the fat sources and the addition levels for any of the analyzed variables, except for the digestibility coefficient of dry matter (DCDM), which was higher in diets added with 2% soybean oil when compared to chicken tallow. The addition of 4% fat in the diet, regardless of fat source, improved the digestibility coefficient of ethereal extract (DCEE) and increased weight gain and feed intake. Moreover, in the initial phase, the addition of 4% fat to the diet increased lipase activity when compared to diets with 2% addition, and a positive correlation between DCEE and pancreatic lipase activity was observed. In conclusion, there is no interaction between fat sources and addition levels, except for DCDM. Carcass characteristics are not influenced by any of the studied factors. The addition of 4% fat increases pancreatic lipase activity and improves DCEE, resulting in greater weight gain, regardless of the tested fat source, making chicken tallow a great alternative to soybean oil.

n-6:n-3 PUFA ratio is involved in regulating lipid metabolism and inflammation in pigs

The objective of the present study was to investigate the optimal dietary n-6:n-3 PUFA ratios that regulate lipid metabolism and inflammation in pigs. A total of ninety-six cross-bred (Large White × Landrace) growing-finishing pigs (73·8 (SEM 1·6) kg) were chosen and fed one of the four isoenergetic diets with n-6:n-3 PUFA ratios of 1:1, 2·5:1, 5:1 and 10:1. The growth performance of pigs fed the diet with an n-6:n-3 PUFA ratio of 5:1 was the best, but the group fed the diet with an n-6:n-3 PUFA ratio of 1:1 had the highest muscle mass and the lowest adipose tissue mass (P< 0·05). The concentrations of IL-6 and IL-1β of pigs fed the diet with an n-6:n-3 PUFA ratio of 1:1 were decreased compared with those of the other groups (P< 0·05). The concentration of adiponectin of pigs fed the diet with an n-6:n-3 PUFA ratio of 1:1 was also markedly decreased, but the concentration of leptin was increased compared with that of the groups fed the diets with n-6:n-3 PUFA ratios of 5:1 and 10:1 (P< 0·05). Additionally, the optimal dietary ratios of n-6:n-3 PUFA of 1:1 and 5:1 markedly suppressed the expression levels of lipid metabolism-related genes and proteins such as phosphoinositide-3-kinase-α, fatty acid transport protein-1 and PPARγ. They also significantly suppressed the expression levels of the inflammatory cytokines IL-1β, TNF-α and IL-6. The results indicated that the optimal n-6:n-3 PUFA ratios of 1:1 and 5:1 exerted beneficial effects on lipid metabolism and inflammatory system, leading to the availability of more energy and nutrients for high performance and homeostatic pathways.

Poultry fat decreased fatty acid transporter protein mRNA expression and affected fatty acid composition in chickens

Background

A study was undertaken to examine the effects of poultry fat (PF) compared with those of soybean oil (SBO) on intestinal development, fatty acid transporter protein (FATP) mRNA expression, and fatty acid composition in broiler chickens. A total of 144 day-old male commercial broilers were randomly allocated to 2 treatment groups (6 replicates of 12 chicks for each treatment) and fed isocaloric diets containing 3.0% PF or 2.7% SBO at 0 to 3 wk and 3.8% PF or 3.5% SBO at 4 to 6 wk, respectively.

Results

PF had no influence on intestinal morphology, weight, or DNA, RNA, or protein concentrations at 2, 4, and 6 wk of age. However, compared with SBO, PF significantly decreased FATP mRNA abundance at 4 wk (P = 0.009) and 6 wk of age (P < 0.001); decreased liver fatty acid-binding protein (L-FABP) mRNA abundance at 6 wk of age (P = 0.039); and decreased C18:2 (P = 0.015), C18:3 (P < 0.001), C20:2 (P = 0.018), Σ-polyunsaturated fatty acids (Σ-PUFA) (P = 0.020), and the proportion of PUFA (P < 0.001) in the intestinal mucosa and decreased C18:2 (P = 0.010), C18:3 (P < 0.001), C20:2 (P < 0.001), Σ-PUFA (P = 0.005), and the proportion of PUFA (P < 0.001) in breast muscle at 6 wk of age.

Conclusions

PF decreases FATP and L-FABP mRNA expression and decreased the proportion of PUFA in the intestinal mucosa and breast muscle.

Effects of flavomycin and probiotic supplementation to diets containing different sources of fat on growth performance, intestinal morphology, apparent metabolizable energy, and fat digestibility in broiler chickens

This study was conducted with broilers to evaluate the effects of growth-promoting antibiotic (flavomycin) and probiotic (7 bacterial species) supplementation in diets containing soybean oil or free fatty acids (FFA) on performance, morphological parameters of the small intestine, apparent digestibility of gross energy (GE) in the ileum, and apparent digestibility of fat in the ileum and total intestinal tract. Eight-hundred and sixty 4-d-old Ross 308 broiler chicks were used in a 3 × 3 factorial arrangement of dietary treatments that comprised 3 additives (without additive, flavomycin, and probiotic) and 3 fat sources (without fat, 30 g/kg of FFA, and 30 g/kg of soybean oil) with 4 pen replicates per treatment. All diets contained chromic oxide (3 g/kg) as an indigestible marker. Body weight and feed intake were recorded weekly over 40 d. Flavomycin interacted positively with soybean oil and FFA causing improvements (P < 0.05) in BW gain. Among the different fat sources, soybean oil significantly increased (P < 0.05) BW gain and jejunal villi height, whereas flavomycin improved (P < 0.05) BW gain and feed conversion when compared with the remaining dietary additives. However, the probiotic negatively affected (P < 0.05) BW gain and feed conversion despite increased (P < 0.05) villi heights of the duodenum, jejunum, and ileum. At 21 and 38 d of age, fat and GE digestibility were higher (P < 0.05) in the ileum and total intestinal tract of birds fed diets containing soybean oil than those of birds fed FFA. Fat and GE digestibility were highest (P < 0.05) among birds fed flavomycin but lowest (P < 0.05) among probiotic-fed birds. Flavomycin addition to soybean oil or FFA diets significantly increased (P < 0.05) fat and GE digestibility when compared with the same diets containing the probiotic. Therefore, soybean oil is a better energy source than FFA, as indicated by increased growth, nutrient digestibility, and jejunal villi height. However, probiotic supplementation to fat-rich diets caused detrimental effects on nutrient digestibility and growth.

Conjugated linoleic acid combined with physical activity reduces body fat accumulation but does not modify lean body mass in male and female Wistar rats

Several biological and clinical studies have suggested that conjugated linoleic acid (CLA) prevents body fat accumulation and increases lean body mass. CLA is available as a concentrated dietary supplement and is purported to provide the aforementioned benefits for people who perform physical activity. This study was conducted to evaluate the effect of a CLA-supplemented diet combined with physical activity on the body composition of Wistar rats. Two groups of Wistar rats of both sexes, between 45 and 60 days old, were fed a diet containing 5.5% soybean oil (control group) or a CLA-supplemented diet (0.5% CLA and 5.0% soybean oil) (test group). Half the rats in both groups were assigned to exercise by running on a treadmill. The biochemical and anatomical body compositions were analyzed. In both groups, CLA had no effect on the dietary consumption or the weight of the liver, heart, and lungs. However, it did influence the overall weight gain of exercised male rats and the chemical and anatomical body composition in exercised and sedentary rats of both sexes. The results confirm that a CLA-supplemented diet with and without physical activity reduced body fat accumulation in rats of both sexes. However, there is no evidence of an increase in the lean body mass of the exercised rats.

Effect of dietary fat sources on fatty acid deposition and lipid metabolism in broiler chickens

The hypothesis tested was that dietary vegetable fats rich in saturated fatty acids, when compared with a vegetable oil rich in linoleic acid, increase fat deposition in broiler chickens and affect synthesis or oxidation, or both, of individual fatty acids. Diets with native sunflower oil (SO), a 50:50 mix of hydrogenated and native SO, palm oil, and randomized palm oil were fed to broiler chickens. Intake of digestible fat and fatty acids, whole body fatty acid deposition, hepatic fatty acid profile, and hepatic enzyme activities involved in fatty acid oxidation and synthesis were measured. The fat deposition:digestible fat intake ratio was significantly lower for the SO group in comparison with the groups fed the vegetable fats rich in saturated fatty acids. The difference between digestible intake and deposition of C18:2, reflecting its maximum disappearance rate, was highest for the SO group and lowest for the palm oil- and randomized palm oil-fed birds. The calculated minimal rate of de novo synthesis of monounsaturated fatty acids (MUFA), calculated as deposition minus digestible intake, was more than 50% lower for the SO group than for the other 3 dietary groups. Based on the fatty acid profiles in the liver, it would appear that increasing contents of C18:2 decrease the desaturation of saturated fatty acids into MUFA. It is concluded that a diet rich in C18:2 in comparison with different kinds of vegetable saturated fatty acids decreases the deposition of fat, especially of MUFA. It appears to be caused by a higher β-oxidation and a reduced de novo synthesis of MUFA, but this conclusion is not fully supported by the measured activities of enzymes involved in fatty acid synthesis and oxidation.

Effects of diet, age and gender on the polyunsaturated fatty acid composition of broiler anatomical compartments

1. The objective of this study was to investigate the effect of dietary fatty acid (FA) composition, age, and gender on the FA composition of different broiler anatomical compartments. Four dietary fat sources (palm fat, P; soybean oil, S; linseed oil, L; fish oil, F) were added to a wheat-soybean meal based diet at 30 g/kg in addition to 50 g/kg palm fat. Diets were fed separately to female and male birds from d 1 to either d 21 or d 42 of age. 2. The total FA content (mg/100 g tissue) and the FA composition (g/100 g FAME) was determined in 7 anatomical compartments (skinless thigh muscle, skinless breast muscle, liver, heart, brain, abdominal fat pad, and remainders plus carcase trimmings named Rest compartment). The FA profiles differed greatly among compartments and were strongly affected by diet. 3. The S diet resulted in a 2-3-fold increase of the proportion of C18:2n-6 and C20:4n-6 in all compartments compared to the other diets, except for brain. 4. The response in the proportion of C18:3n-3 following feeding the L diet was much greater, with 4-20-fold increases compared to the other diets, except again for brain. 5. In all compartments except brain, the L diet resulted in approximately a 2-fold increase in the proportion of C22:6n-3 compared to the P and S diets and smaller, but also significant, increases for C20:5n-3 and C22:5n-3. 6. The proportions of C20:5n-3, C22:5n-3 and C22:6n-3 were much higher on the F diet in all compartments, except for brain, compared to the P and S diets. The F diet resulted in higher proportions of C22:6n-3 than the proportions of C20:5n-3 and C22:5n-3 in breast and thigh meat, and liver, in contrast to the other diets. 7. Brain was less responsive than other tissues to changes in the dietary FA composition. The proportion of C22:6n-3 in brain was similar on the L and F diets. 8. The effect of gender on the FA composition of different anatomical compartments was marginal. The long-chain n-3 and n-6 PUFA in breast, liver, and brain decreased with age.

Effect of dietary omega6/omega3 on growth performance, carcass traits, meat quality and fatty acid profiles of Beijing-you chicken

The effects of varying the omega6 to omega3 fatty acid ratio (omega6/omega3) of diets on growth performance, carcass traits, meat quality and fatty acid composition of breast muscle were investigated in Beijing-you chickens grown to 92 days. A total of 360 one-day-old female BJY chickens were fed diets containing 0%, 0.12%, 0.42%, 1.00% or 1.97% linseed oil replacing equal weights of maize oil to make dietary omega6/omega3 to be approximately 30:1, 20:1, 10:1, 5:1 and 2.5:1. Subcutaneous fat thickness and intramuscular fat content increased significantly in birds fed up to 10:1 omega6/omega3. a* values (redness of meat, dimension of the CIELAB-system) progressively increased as the diets contained increasing omega3 content, up to the 10:1 omega6/omega3.The changes in b* (yellowness of meat, dimensions of the CIELAB-system) were also significant but the pattern was almost the reverse of changes in a*. Shear force increased significantly as dietary omega6/omega3 was reduced from 30:1 to 5:1. Decreasing the dietary omega6/omega3 clearly decreased the content in breast muscle of C20:1 and C22:1, but increased that of C24:1. C20:4, C20:5 and C22:5, increased significantly by decreasing the dietary omega6/omega3, and the birds fed the 10:1 diet had higher contents of C22:6 than other treatments. This study has clearly demonstrated that decreasing the dietary omega6/omega3, increases the deposition of desirable omega3 and omega6 long chain PUFA in the edible tissue, thereby achieving nutritionally enriched meat.