Effects of peroxidized soybean oil on growth and energy digestibility in broilers

Peroxidized lipids have been shown to reduce broiler performance whereupon it was theorized that dietary peroxide value (PV) plus anisidine value (AnV) may be predictive of broiler performance. In experiment (EXP) 1, 64 pens (8 broilers/pen) were fed diets containing 8 levels of peroxidized soybean oil (SO). Broilers were fed diets from 7 to 35 d of age with 8 replications per dietary treatment. Broilers fed diets containing SO processed at 135°C resulted in a reduction in average daily gain (ADG) and average daily feed intake (ADFI, P ≤ 0.05) compared to birds fed diets containing the unheated SO while birds fed diets containing SO processed at 90°C resulted in a reduction in gain to feed (GF, P ≤ 0.05) compared to birds fed diets containing the unheated SO. Summarization of this data with published data resulted in significant (P ≤ 0.01) regression models for relative ADG [ADG, % = 101.9 - (0.05 × PV) - (0.30 × AnV), SE = 4.1, R2 = 0.43], ADFI [ADFI, % = 101.7 - (0.09 × PV) - (0.19 × AnV), SE = 3.3, R2 = 0.32], and GF [GF, % = 100.4 + (0.05 × PV) - (0.14 × AnV), SE = 2.6, R2 = 0.27], albeit PV was not a significant regression parameter (P ≥ 0.36) for any equation. In EXP 2, the TMEn of four different SO was determined using the precision-fed rooster assay. Diets consisted of ground corn with SO added at 0, 7.5 or 15 % of the diet at the expense of ground corn with 4 roosters per treatment. Relative bioavailability (RBV) was determined using slope-ratio methodology where it was determined that the reduction in the RBV of peroxidized SO ranged from 12 to 29 percent compared to the unheated SO sample. These data suggests that bird performance relative to birds consuming unperoxidized lipids can be predicted based on dietary levels of PV and AnV, although the slopes for performance decline are relatively flat with the combination of PV and AnV accounting for 27 to 43 % of the response variable variance.

Effects of dietary metabolizable energy density and inclusion of oxidized soybean oil on the growth performance, serum biochemical parameters, redox status, and wooden breast incidence of broilers

Dietary nutrients not only affect the growth and pectoralis muscle production of broilers but also are related to the occurrence of pectoralis myopathies, such as wooden breast (WB) and white striping. We investigated whether dietary metabolizable energy (ME) densities and inclusion of oxidized soybean oil could affect growth performance, serum biochemical parameters, redox status, and incidence of WB in broilers. One hundred and forty-four 21-d-old Arbor Acres male broilers were assigned into four experimental diets using a 2 × 2 factorial arrangement, including two ME densities (3,100 and 3,220 kcal/kg) and two soybean oil types (Fresh oil with peroxide value = 10.23 mEq/kg or oxidized oil with peroxide value = 122.93 mEq/kg). The experiment lasted for 21 d. The results demonstrated that high ME diets increased broiler body weight gain (BWG) by11.02%, feed intake (FI) by 4.98%, and abdominal fat percentage by 17.92%, while decreased feed-to-gain (F/G) ratio by 3.39% (P < 0.05). Oxidized soybean oil diets increased F/G ratio by 2.92% (P < 0.05) and had a tendency to decrease BWG of birds (P = 0.08). Simultaneously, high ME diets increased concentrations of serum triglyceride, malondialdehyde, and protein carbonyl (PC) (P < 0.05). Concurrently, oxidized soybean oil elevated activity of serum aspartate aminotransferase and concentrations of glucose, high-density lipoprotein, and total bile acid (P < 0.05). Meanwhile, oxidized soybean oil diets increased PC concentration and total antioxidant capacity activity in serum of birds (P < 0.05). Moreover, the high ME diet containing oxidized soybean oil decreased serum albumin and low-density lipoprotein levels (P < 0.05). Additionally, the incidence of WB was increaseed in broilers fed with high ME diets compared to the lower ME diets (57.97% vs. 33.80%; P < 0.05), and the incidence of WB in the oxidized soybean oil group was higher than that in the fresh soybean oil group (50.73% vs. 40.85%; P < 0.05). Meanwhile, the incidence of moderate and severe WB myopathy was highest in broilers fed high ME diet with oxidized soybean oil, which led to a substantial increase in cellular vacuolization, widespread inflammatory infiltration, and a marked thickening of the intercellular matrix, indicating more severe degradation of myofiber tissue. Thus, we concluded that the combination of high ME and oxidized soybean oil in diets negatively affected broiler growth performance, serum biochemistry, and redox homeostasis, and significantly elevated overall WB incidence and exacerbated pathological severity.

Energy digestibility in broilers and poult performance when fed palm or soybean oil with or without glyceryl monolaurate

Two trials were conducted to determine interactive effects between lipid source (palm oil, PO versus soybean oil, SO) and emulsifier addition (none versus glycerol monolaurate-GML) on apparent total tract digestibility (ATTD) of gross energy (GE) in broilers and growth performance in poults. In trial 1, 0.05 % GML addition had no impact on the ATTD of GE of SO but improved the ATTD of PO from 77.11 % to 88.21 % (interaction, P=0.03). Without GML addition, PO had a lower ATTD of GE (77.11 %) compared to SO (96.48 %) resulting in an AME of 7,259 versus 9,092 kcal/kg for PO and SO, respectively. In trial 2, the addition of 0.10 % GML reduced ADFI in poults fed diets containing 5 % PO compared to poults fed 0 or 0.05 % GML, while the addition of either 0.05 or 0.10 % GML reduced ADFI in poults fed diets containing 5 % SO compared to poults fed no GML (P=0.01). There was a similar response with ADG (P=0.01) where the addition of either 0.05 or 0.10 % GML reduced ADG in poults fed diets containing SO compared to poults fed no GML, while the addition of GML was largely without effect in poults fed diets containing PO. There was no interaction between lipid source and emulsifier addition on feed efficiency (P>0.10). Poults fed diets containing PO had a poorer feed efficiency compared to birds fed diets containing SO (P=0.01). The main effect of emulsifier was inconsistent in that poults fed the diets containing 0.10 % GML had the greatest feed efficiency compared to poults fed the diets containing 0.05 % GML, with poults fed diets containing no emulsifier being intermediate (P=0.10). In conclusion, addition of GML improved the ATTD of GE for PO but had no effect on the ATTD of GE for SO. This improvement in energy digestibility, did not however, translate to an improvement in poult performance. Broilers and poults fed diets containing SO had a greater feed efficiency compared to birds fed diets containing PO.

Influence of grain type and fat source on performance, nutrient utilization, and gut properties in broilers fed pelleted diets

The influence of grain type and fat source on the performance, coefficient of apparent ileal digestibility (CAID), and intestinal characteristics in broiler starters fed pelleted diets were studied. The experiment included 8 treatments arranged as a 2 × 4 factorial with 2 grains (wheat and corn) and 4 fat sources (soybean oil, fish oil, tallow, and palm oil). In all fat sources, corn-fed birds had a higher weight gain than those fed wheat-based diets. However, improvement in the weight gain of birds fed wheat-based diets supplemented with tallow resulted in a significant (P < 0.001) interaction between grain type and fat source. Inclusion of wheat and tallow increased feed intake compared to corn and other fat sources, respectively. Pellets made from wheat were harder (P < 0.01) than those based on corn. Broilers fed corn-based diets, had higher CAID of fat, Ca, and phosphorus (P < 0.01) than those fed wheat-based diets. Soybean oil inclusion, also increased (P < 0.01) fat digestibility compared to other fat sources. An interaction occurred between grain type and fat source where pellets made from corn and soybean oil had higher protein digestibility compared to the other treatments (P < 0.01). Feeding wheat-based diets increased pH of gizzard and proventriculus compared to corn-based diets (P < 0.01). Highest viscosity value was observed in wheat-diets supplemented with fish oil, and palm oil (P < 0.01). The pancrease, gizzard and cecum were heavier in corn-based fed birds compared to those fed wheat-based diets (P < 0.01). A significant interaction between grain type and fat source was noted for Lactobacillus spp. and the total anaerobic bacteria population in the cecum. Overall, the effect of grain type on weight gain, CIAD of protein and cecal microbiota differed depending on the fat sources. Feeding corn and soybean oil resulted in better gut development and growth performance in broilers fed pelleted diets.

Assessing different oil sources efficacy in reducing environmental heat-stress effects via improving performance, digestive enzymes, antioxidant status, and meat quality

Adding oil to the feed of genetically improved broilers is necessary to provide energy requirements, in addition to enhancing metabolism, growth performance, immune response. This study aims to reveal the effect of adding different oil sources in the diets of broilers exposed to environmental heat stress on performance, digestibility, oxidative status, plasma lipids, fatty acids content, and meat quality. Six hundred twenty-five one-day-old broiler chicks were randomly distributed to five groups as follows: the first group fed a diet without oil (CON) as a control, while the second to the fifth group fed a diet containing soy oil (SO), corn oil (CO), olive oil (OO), and fish oil (FO), respectively. Results indicated a significant deterioration in growth performance, carcass traits, and oxidative state with a significant decrease in carcass quality in heat-stressed chickens fed the CON diet. Results showed increased growth, enhanced feed conversion ratio, and carcass dressing in broilers fed the oil-supplemented diet compared to the control diet, however, the digestive enzymes activity was not affected by receiving an oil-supplemented diet. The best performance was in chickens fed OO and SO, compared with FO and CO. Plasma aspartate aminotransferase (AST), and alanine aminotransferase (ALT) increased in broilers fed an oil-supplemented diet. Plasma high-density lipoprotein (HDL), and superoxide dismutase (SOD) remarkably increased in broilers fed OO, whereas the malondialdehyde (MDA) decreased compared to the other groups. Adding different dietary oil sources enhanced the breast muscle's fatty acid composition. Broiler diets supplemented with oils positively affected meat quality by enhancing color measurements, and TBA values, while the best were in chicken fed OO. It was concluded that adding dietary oil at 3% in the diets of broiler chicken exposed to environmental heat stress positively affected growth performance, enhanced oxidative status, and meat quality, best results were in broilers fed a diet that included olive oil.

Role of Dietary Methyl Sulfonyl Methane in Poultry

Oxidative stress is defined as an imbalance between pro-oxidants and anti-oxidants within biological systems, leading to tissue damage and compromising the health of afflicted animals. The incorporation of dietary anti-oxidants into chicken diets has been a common practice to improve the performance, health, and welfare of the host by protecting against oxidative stress-induced damage. Methyl sulfonyl methane (MSM), a naturally occurring organosulfur compound found in various plant sources, has demonstrated various beneficial biological properties, including anti-inflammatory and anti-oxidant properties in both in vitro and in vivo studies. MSM has been utilized as a dietary supplement for humans for its anti-oxidant, analgesic, and anti-inflammatory properties. It has also been administered to domestic animals, including cattle, pigs, and chickens, owing to its recognized anti-oxidant effect. This review summarizes the biological and physiological functions of dietary MSM in poultry.

Effect of chelated source of additional zinc and selenium on performance, yolk fatty acid composition, and oxidative stability in laying hens fed with oxidised oil

1. The following study determined whether the effects of the combined addition of zinc amino acid complex (ZA) and selenomethionine (SM) was superior to their single addition in controlling the oxidative stress induced by dietary oxidised fat in laying hens.2. Two hundred and forty 32-week-old laying hens were divided into the following dietary treatments (each consisting of six replicates of eight birds): 1) a fresh soy oil (FSO) diet; 2) an oxidised soy oil (OSO) diet; 3) an OSO diet plus 20 mg zinc as ZA/kg (OSO+ZA); 4) an OSO diet plus 0.2 mg selenium as SM/kg (OSO+SM); and 5) an OSO diet plus ZA and SM (OSO+ZA+SM).3. After 10 weeks of feeding hens, feed intake, egg production, and egg mass in the OSO+ZA+SM group were similar to the FSO group but better (P<0.05) than those in the OSO group. Shell thickness and shell breaking strength were significantly improved by the OSO+ZA and OSO+ZA+SM treatments.4. Increases in the yolk concentrations of palmitic acid and total saturated fatty acids (SFA), and decreases in yolk linoleic acid, n-6 polyunsaturated fatty acids (PUFA), total PUFA, and PUFA/SFA ratio were induced by dietary oxidised fat which were normalised (P<0.05) by OSO+SM and OSO+ZA+SM.5. An increase (P<0.05) in malondialdehyde and a decrease in 2,2-diphenyl-picrylhydrazyl radical scavenging activity in the yolk, induced by dietary oxidised fat, was significantly improved by all dietary supplementations, but only birds fed the OSO+ZA+SM diet exhibited similar values to those fed FSO.6. In conclusion, the simultaneous inclusion of organic zinc plus selenium in the oxidised fat diets was beneficial for improving egg-laying performance, yolk fatty acid profile, and oxidative stability, but not for internal egg quality, compared with either zinc or selenium alone in laying hens.

Oxidative Quality of Acid Oils and Fatty Acid Distillates Used in Animal Feeding

Simple Summary

Feed producers and farmers seek alternative and economical fat ingredients to supply animals with energy and beneficial components, such as natural antioxidants. Some byproducts from the edible oil refining industry, such as acid oils (AO) and fatty acid distillates (FAD), fulfil these requirements, but differences in the animal performance have been reported as their main drawback, which might be due to their high variable composition, including their oxidation status. Therefore, the valorization of these byproducts as feed ingredients requires ensuring standardized products with adequate quality in terms of oxidation parameters. In this study, 92 AO and FAD were characterized, finding a huge variability in their oxidation status and stability. They all showed low primary oxidation values (peroxide values). The content of secondary oxidation compounds was higher in FAD (which are released from physical refining processes) than in AO (which originate from chemical refining), while polymeric compounds were higher in the latter. The fatty acid and tocol compositions that were related with the botanical origin influenced their oxidative stability. Thus, in the quality control of these products, apart from the compositional parameters, it is recommended to include the evaluation of the oxidation status, both by primary and secondary oxidation parameters.

Abstract

Acid oils (AO) and fatty acid distillates (FAD) are byproducts from chemical and physical refining of edible oils and fats, respectively. Their high energy value makes their upcycling interesting as alternatives to conventional fats in animal feeding. The objective of this study is to characterize their oxidative quality and to provide recommendations about their evaluation for animal feeding purposes. The oxidation status (peroxide value (PV), p-Anisidine value (p-AnV), % polymeric compounds (POL)), the oxidative stability (induction time by the Rancimat at 120 °C (IT)), the fatty acid composition (FA), and tocopherol and tocotrienol content of 92 AO and FAD samples from the Spanish market were analyzed. Both AO and FAD showed low PV (0.8 and 1 meq O₂/kg); however, p-AnV was higher in FAD (36.4 vs. 16.4 in AO) and POL was higher in AO (2.5% vs. not detected in FAD) as a consequence of the type of refining process. The botanical origin of AO and FAD influenced FA and tocol composition, and they influenced IT. A high variability was observed for most analyzed parameters, reinforcing the need for standardizing AO and FAD to obtain reliable feed ingredients and to include primary and secondary oxidative parameters within their quality control.

Assessment of the quality, oxidative status and dietary energy value of lipids used in non-ruminant animal nutrition

BACKGROUND

Fats and oils represent the most concentrated source of energy available to animal nutritionists and form an expensive part of the diet. Thorough understanding of lipid quality and composition are required for efficient and precise diet formulation. Therefore, 724 samples of commercially available fats and oils were assessed for fatty acid profile, oxidation status and energetic value as per the Wiseman equation, with consideration of a correction factor K, which is based on the presence of the energy diluting compounds moisture, impurities and unsaponifiables.

RESULTS

Energy diluting compounds were widespread across fat types and sources. Average MIU (moisture, insoluble impurities and unsaponifiable matter) presence in individual oils was 5.1-28.1 g kg^-1 . Using the adapted Wiseman equation presented in the current paper, which reflects the energy diluting potential of MIU, the calculated energy values of fats and oils is reduced by up to 46% in extreme cases compared to those predicted by the original equation. From the chemical parameters, it is clear that there is limited correlation between individual measures of oxidation, with only weak negative correlations between 2-thiobarbituric acid (TBA) and Oxidative Stability Index (OSI) values (Spearman's ρ between -0.20 and -0.39) and a weak to moderate negative correlation between peroxide value (PV) and OSI (Spearman's ρ between -0.20 and -0.59) for certain fats and oils. A moderate to very strong positive correlation between FFA and the energy diluting compounds MIU was observed for all animal fats (Spearman's ρ between 0.40 and 1.00).

CONCLUSION

The current report highlights the large variation in composition and quality seen in commercially available fats and oils and encourages ongoing analysis and assessment rather than reliance on published values. The results also indicate that the oxidation parameters when interpreted as separate values lack the power of inferring oil and fat quality. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

The effects of supplementation of Withania coagulans and α-tocopherol acetate in diets containing oxidised oil on growth performance, immune response and antioxidant indices in broiler chickens

This experiment was designed to study the effects of a hydroalcoholic fruit extract from Withania coagulans (WC) and α-tocopherol acetate (α-Toc) in diets containing oxidised oil on growth performance, immune response and antioxidant indices of broiler chickens. The experiment was arranged 2 × 3 × 2 factorial comprising the oxidised oil (0% and 2% diet), WC (0, 100 and 200 mg/kg diet) and α-Toc (0 and 200 mg/kg diet). A total of 600 1-day-old male broiler chickens of the Ross strain were randomly allocated to 12 treatments with 5 replicates of 10 birds each. On day 42, one bird from each replicate was sacrified to measure the lymphoid organ weights, intestinal morphometric characteristics, and malondialdehyde content in the thigh meat. Dietary inclusion of oxidised oil significantly reduced the body weight gain in birds receiving no dietary WC (p < 0.05). In contrast, dietary supplementation of WC at 100 mg/kg diet in birds fed with the diets lacking in WC and oxidised oil resulted in significant increase in body weight gain (p < 0.05). Dietary supplementation of WC significantly increased the total anti-sheep red blood cell titre (p < 0.01). The birds fed with the dietary oxidised oil revealed significantly higher values of malondialdehyde and lower glutathione peroxidase and superoxide dismutase activities (p < 0.05). Feeding diets containing WC resulted in a significant decrease in malondialdehyde content in thigh meat while conversely, increased the glutathione peroxidase and superoxide dismutase activities (p < 0.05). The findings indicated that the dietary inclusion of WC could be recommended as a potent alternative to synthetic compounds in order to improve broilers performance, immunity and meat quality under oxidative stress conditions.

Inclusion of vegetable oils in diets of broiler chicken raised in hot weather and effects on antioxidant capacity, lipid components in the blood and immune responses

The aim of this study was to assess the effects of vegetable oils on the antioxidant capacity, blood lipid components and immune responses in chickens raised in hot climate. In a completely randomized design, 300 chicks were assigned to four treatments and five replicates with 15 chicks per each. The highest concentration of malondialdehyde was found in broilers fed palm oil (p < 0.05). Chickens fed corn oil had the lowest and those fed flaxseed oil had the highest antioxidant enzymes activities (p < 0.05). The highest hepatic Alanine-transferase and Aspartate-transferase was found in chickens fed corn oil and the lowest levels in those received flaxseed and olive oils (p < 0.05). The highest hypersensitivity was in chickens fed palm oil and the lowest was for olive oil. The highest antibody titer against sheep red blood cells was found in chickens fed flaxseed oil and the lowest titer was for those received palm oil (p < 0.05). The highest triglyceride, cholesterol and very low density lipoprotein and the lowest high density lipoprotein was found in chickens fed palm oil and vice versa for flaxseed and olive oils. Olive and flaxseed oils had beneficial effects on antioxidant activity and lipid attributes and palm oil had detrimental effects on these parameters that related to the poultry health.

Effects of ND vaccination combined LPS on growth performance, antioxidant performance and lipid metabolism of broiler

Newcastle Disease Virus (NDV) is the important pathogen of Newcastle Disease (ND) attacking chicken, turkey and other birds. Therefore, the purpose of this study was to assess the effects of immune stress induced by ND vaccination and lipopolysaccharide (LPS) on growth performance, antioxidant ability, and lipid metabolism of broilers. In total, 128 one-day-old broilers were randomly assigned to the following four groups and were treated as indicated: normal control (NC); vaccinated with live LaSota ND vaccine (CV); administered ND vaccine and 0.25 mg/kg body weight (BW) LPS (L-LPS); and administered ND vaccine and 0.5 mg/kg BW LPS (H-LPS). The results demonstrated that broiler feed conversion ratio (FCR) was increased in the groups CV, L-LPS and H-LPS from d 0 to 42 days compared with the group NC. The antioxidant function of broilers was decreased as indicated by the malondialdehyde (MDA) and glutathione peroxidase (GSH-Px) levels in the serum of the treated groups. ND vaccination combined LPS increased the concentration of total cholesterol (TC), triglyceride (TG) and low-density lipoprotein cholesterol (LDL-C), but decreased the concentration of high-density lipoprotein cholesterol (HDLC) compared with the group NC. The reverse transcription (RT)-PCR results revealed that the mRNA expression of acetyl-CoA carboxylase gene (ACC) and 3-hydroxy-3-methylglutaryl coenzyme-A reductase (HMGR) in the liver were downregulated, whereas the mRNA expression of carnitine palmitoyltransferase-1 (CPT-1) and peroxisome proliferator-activated receptor (PPAR)-α were upregulated compared with the group NC. These results suggest that ND vaccination combined LPS reduced broiler growth performance and antioxidant ability, whereas it activated AMPK-mediated lipid metabolism.

Influence of feeding thermally peroxidized lipids on growth performance, lipid digestibility, and oxidative status in nursery pigs

Three experiments were conducted to evaluate oil source and peroxidation status (experiment 1) or peroxidized soybean oil (SO; experiments 2 and 3) on growth performance, oxidative stress, and digestibility of dietary ether extract (EE). In experiment 1, palm oil (PO), poultry fat (PF), canola oil (CO), and SO were evaluated, while in experiments 2 and 3, only SO was evaluated. Lipids were either an unheated control (CNT) or thermally processed at 90 °C for 72 hr, being added at 10%, 7.5%, or 3% of the diet in experiments 1, 2, and 3, respectively. In experiment 1, 288 pigs (body weight, BW, 6.1 kg) were fed 1 of 8 factorially arranged treatments with the first factor being lipid source (PO, PF, CO, and SO) and the second factor being peroxidation status (CNT or peroxidized). In experiment 2, 216 pigs (BW 5.8 kg) were fed 1 of 6 treatments consisting of 100%, 90%, 80%, 60%, 20%, and 0% CNT SO blended with 0%, 10%, 20%, 40%, 80%, and 100% peroxidized SO, respectively. In experiment 3, 72 pigs (BW 5.8 kg) were fed either CNT or peroxidized SO. Pigs were fed 21 d with feces collected on day 12 or 14 and pigs bled on day 12 blood collection. In experiment 1, an interaction between oil source and peroxidation status was observed for averaged daily gain (ADG) and average daily feed intake (ADFI; P = 0.10) which was due to no impact of feeding pigs peroxidized PO, PF, or SO on ADG or ADFI compared with feeding pigs CNT PO, PF, or SO, respectively; while pigs fed peroxidized CO resulted in reduced ADG and ADFI compared with pigs fed CNT CO. There was no interaction between oil source and peroxidation status, and no lipid source effect on gain to feed ratio (GF; P ≥ 0.84), but pigs fed the peroxidized lipids had a lower GF compared with pigs fed the CNT lipids (P = 0.09). In experiment 2, feeding pigs diets containing increasing levels of peroxidized SO resulted in reduced ADG (quadratic, P = 0.03), ADFI (linear, P = 0.01), and GF (quadratic, P = 0.01). In experiment 3, feeding peroxidized SO at 3% of the diet reduced ADG (P = 0.11) and ADFI (P = 0.13), with no observed change in GF (P = 0.62). Differences in plasma protein carbonyls, glutathione peroxidase, and vitamin E due to feeding peroxidized lipids were inconsistent across the 3 experiments. Digestibility of dietary EE was reduced in pigs fed peroxidized PO or SO (P = 0.01, experiment 1) and peroxidized SO in experiments 2 and 3 (P ≤ 0.02). In conclusion, the peroxidation status of dietary lipids consistently affects growth performance and EE digestibility but has a variable effect on measures of oxidative stress.

Effects of dietary oxidized oil on growth performance, meat quality and biochemical indices in poultry – a review

Lipids (fats and oils) are a concentrated source of energy in poultry diets that improves palatability, feed consistency, provides essential fatty acids and increases the absorption of fat-soluble vitamins. Fresh oil is an expensive energy source and its exposure to air, heat, metallic catalyst during storage and processing may lead to its oxidative deterioration. This review highlights the response of modern poultry to dietary oxidized oil on growth performance, nutrients digestibility, gut health, carcass characteristics, meat quality, blood chemistry and tissue oxidative status. Literature shows that in moderately (peroxide value (PV): 20 to 50 meq kg−1) and highly (PV: 50 to 100 meq kg−1 or above) oxidized oils, lipid peroxidation causes rancid odours and flavours that negatively affect feed palatability, reduces intestinal villus height that decreases the surface area available for nutrients absorption. The oxidation products also damage fat soluble vitamins (A, D, E and K) in blood resulting in an oxidative stress. The use of oxidized oil in poultry diets has no significant effect on dressing percentage, pH and meat colour, whereas carcass weight decreases and drip loss of meat increases. Overall, there is a contradictory data regarding the influence of oxidized oil in poultry feed depending on the PV and inclusion levels. The reviewed literature shows that the use of mildly oxidized (PV < 20 meq kg−1) oil in poultry feed with 4 to 5% inclusion level decreases the feed cost and ultimately cost of poultry production without compromising their growth performance. It can, therefore, partially replace fresh oil as an efficient, cost effective and sustainable energy source in poultry diets.

Lipid Source and Peroxidation Status Alter Immune Cell Recruitment in Broiler Chicken Ileum

BACKGROUND

Restaurant oil in poultry diets increases energy content, reduces production costs, and promotes sustainability within the food supply chain. However, variable oil composition and heating temperatures among restaurant oil sources can impact broiler chicken health due to heat-induced lipid modifications.

OBJECTIVES

A 21-d experiment was conducted to evaluate ileal morphology, liver cytokine gene expression, and ileal immune cell populations in broilers fed control or peroxidized lipids with varying chain and saturation characteristics.

METHODS

Day-old broilers were housed in battery cages (5 birds per cage) and fed diets containing 5% control or peroxidized oils. Eight diets were randomly assigned in a 4 × 2 factorial arrangement consisting of oil source (palm, soybean, flaxseed, or fish) and peroxidation status (control or peroxidized). At day 21, samples were collected for ileal histomorphology [villus height (VH), crypt depth (CrD), and the VH:CrD ratio], and liver cytokine expression (qPCR). Ileum cytokine expression and T-cell markers were analyzed by RNAscope in situ hybridization (ISH). Data were analyzed as a mixed model (SAS 9.4) with fixed effects of lipid source, peroxidation, and lipid × peroxidation interaction.

RESULTS

CD3+ T-cells in the ileum decreased 16.2% due to peroxidation (P = 0.001) with 30.3% reductions observed in birds fed peroxidized flaxseed oil (P = 0.01). Peroxidation increased IL6+ and IL1B+ cells by 62.0% and 40.3%, respectively (P = 0.01). Soybean oil increased IFNG+ cells by 55.1% compared with palm oil, regardless of peroxidation status (P = 0.007). Lipid source and peroxidation did not alter ileal histomorphology or liver cytokine expression.

CONCLUSIONS

Lipid peroxidation increased ileal IL1B and IL6 in broiler chickens, whereas soybean oil diets increased IFNG. Generally, peroxidation decreased overall CD3+ T-cell populations, suggesting impaired T-cell presence or recruitment. These results identify potential immunomodulatory lipid profiles in restaurant oil while supporting RNAscope-ISH as a method to describe avian tissue-level immune responses.

Changes in markers of lipid oxidation and thermal treatment in feed-grade fats and oils

BACKGROUND

Oxidized feed lipids have been shown to have detrimental effects on food animal growth and metabolism. The present study aimed to measure classes of lipid oxidation products (LOP) in feed-grade oils at temperatures representing production and storage conditions.

RESULTS

There were significant oil type × time interactions in the accumulation of primary and secondary LOP. At 22.5 °C, peroxide value (PV), a marker for the primary phase of lipid oxidation, increased most in fish oil (FO), followed by tallow (TL), soybean oil (SO), linseed oil (LO) and modified algae oil (MAO), whereas palm oil (PO) showed no appreciable increase in PV. Secondary LOP, such as p-anisidine value, hexanal, 2,4,-decadienal, polymerized triacylglycerols and total polar compounds, increased only in FO. At 45 °C, FO and SO produced both primary and secondary LOP, whereas MAO, PO and TL had slower rates of PV increase and no secondary LOP. At 90 °C and 180 °C, all oils except for FO accumulated both primary and secondary LOP.

CONCLUSIONS

Higher polyunsaturated fatty acid:saturated fatty acid oils and higher temperatures produced greater quantities of primary and secondary LOP. However, unrefined TL was more prone to oxidation at 22.5 °C than predicted, whereas LO was more stable than predicted, indicating that pro-oxidant and antioxidant compounds can markedly influence the rate of oxidation. Measuring both primary and secondary LOP will provide better information about the oxidative status of feed oils and provide better information about which classes of LOP are responsible for detrimental health effects in animals. Published 2020. This article is a U.S. Government work and is in the public domain in the USA.

Identification of C9-C11 unsaturated aldehydes as prediction markers of growth and feed intake for non-ruminant animals fed oxidized soybean oil

Background

The benefits of using the oxidized oils from rendering and recycling as an economic source of lipids and energy in animal feed always coexist with the concerns that diverse degradation products in these oxidized oils can negatively affect animal health and performance. Therefore, the quality markers that predict growth performance could be useful when feeding oxidized oils to non-ruminants. However, the correlations between growth performance and chemical profiles of oxidized oils have not been well examined. In this study, six thermally oxidized soybean oils (OSOs) with a wide range of quality measures were prepared under different processing temperatures and processing durations, including 45 °C-336 h; 67.5 °C-168 h; 90 °C-84 h; 135 °C-42 h; 180 °C-21 h; and 225 °C-10.5 h. Broilers and nursery pigs were randomly assigned to diets containing either unheated control soybean oil or one of six OSOs. Animal performance was determined by measuring body weight gain, feed intake, and gain to feed ratio. The chemical profiles of OSOs were first evaluated by common indicative tests, including peroxide value, thiobarbituric acid reactive substances, p-anisidine value, free fatty acids, oxidized fatty acids, unsaponifiable matter, insoluble impurities, and moisture, and then analyzed by the liquid chromatography-mass spectrometry-based chemometric analysis.

Results

Among common quality indicators, p-anisidine value (AnV), which reflects the level of carbonyl compounds, had the greatest inverse correlation with the growth performance of both broilers and pigs, followed by free fatty acids and oxidized fatty acids. Among the 17 aldehydes identified in OSOs, C9-C11 alkenals, especially 2-decenal and 2-undecenal, had stronger inverse correlations (r < − 0.8) with animal performance compared to C5-C8 saturated alkanals, suggesting that chain length and unsaturation level affect the toxicity of aldehydes.

Conclusions

As the major lipid oxidation products contributing to the AnV, individual C9-C11 unsaturated aldehydes in heavily-oxidized oils could function as effective prediction markers of growth and feed intake in feeding non-ruminants.

Molecular cloning, tissue distribution and the expression of cystine/glutamate exchanger (xCT, SLC7A11) in different tissues during development in broiler chickens

The cystine/glutamate exchanger (xCT, SLC7A11) is a component of the system X_c amino-acid antiporter that is able to export glutamate and import cysteine into cells. The xCT amino acid exchanger has received a lot of attention, due to the fact that cysteine is an essential substrate for the synthesis of glutathione (GSH), an endogenous antioxidant in cells. The objective of this research was to clone the full-length cDNA of chicken xCT, and to investigate the gene expression of xCT in different tissues, including intestinal segments of broiler chickens during development. The full-length cDNA of chicken xCT (2,703 bp) was obtained from the jejunum by reverse transcription-PCR and sequenced. Homology tests showed that chicken xCT had 80.4%, 80.2%, and 71.2% homology at the nucleotide level with humans, cattle, and rats, respectively. Likewise, amino acid sequence analysis showed that chicken xCT protein is 86.4%, 79.3%, and 75.6% homologous with humans, cattle, and rats, respectively. Additionally, phylogenetic analysis indicated that chicken xCT genes share a closer genetic relationship with humans and cattle, than with rats. The chicken xCT protein has 12 transmembrane helixes, 6 extracellular loops, and 5 intracellular loops. The mRNA of xCT was detected in all tissues, including intestinal segments, in which the mRNA expression of xCT was significantly higher (P < 0.05) within the colon, compared to the jejunum and ileum. During development, a linear pattern of changes regarding the levels of the xCT mRNA was found, indicating that there was an abundance of xCT within the duodenum (P < 0.05). Furthermore, there were changes of the xCT mRNA abundance in the colon during development, which displayed linear and cubic patterns (P < 0.05). These results indicated that xCT is widely expressed both in intestinal segments, as well as other organs that are not associated with nutrient absorption. Further investigation is needed to characterize the functional relevance of xCT activity in oxidative stress and inflammation in the small intestine of broiler chickens.

Growth performance, oxidative stress and immune status of newly weaned pigs fed peroxidized lipids with or without supplemental vitamin E or polyphenols

Background

This study evaluated the use of dietary vitamin E and polyphenols on growth, immune and oxidative status of weaned pigs fed peroxidized lipids. A total of 192 piglets (21 days of age and body weight of 6.62 ± 1.04 kg) were assigned within sex and weight blocks to a 2 × 3 factorial arrangement using 48 pens with 4 pigs per pen. Dietary treatments consisted of lipid peroxidation (6% edible soybean oil or 6% peroxidized soybean oil), and antioxidant supplementation (control diet containing 33 IU/kg DL-α-tocopheryl-acetate; control with 200 IU/kg additional dl-α-tocopheryl-acetate; or control with 400 mg/kg polyphenols). Pigs were fed in 2 phases for 14 and 21 days, respectively.

Results

Peroxidation of oil for 12 days at 80 °C with exposure to 50 L/min of air substantially increased peroxide values, anisidine value, hexanal, and 2,4-decadienal concentrations. Feeding peroxidized lipids decreased (P < 0.001) body weight (23.16 vs. 18.74 kg), daily gain (473 vs. 346 g/d), daily feed intake (658 vs. 535 g/d) and gain:feed ratio (719 vs. 647 g/kg). Lipid peroxidation decreased serum vitamin E (P < 0.001) and this decrease was larger on day 35 (1.82 vs. 0.81 mg/kg) than day 14 (1.95 vs. 1.38 mg/kg). Supplemental vitamin E, but not polyphenols, increased (P ≤ 0.002) serum vitamin E by 84% and 22% for control and peroxidized diets, respectively (interaction, P = 0.001). Serum malondialdehyde decreased (P < 0.001) with peroxidation on day 14, but not day 35 and protein carbonyl increased (P < 0.001) with peroxidation on day 35, but not day 14. Serum 8-hydroxydeoxyguanosine was not affected (P > 0.05). Total antioxidant capacity decreased with peroxidation (P < 0.001) and increased with vitamin E (P = 0.065) and polyphenols (P = 0.046) for the control oil diet only. Serum cytokine concentrations increased with feeding peroxidized lipids on day 35, but were not affected by antioxidant supplementation (P > 0.05).

Conclusion

Feeding peroxidized lipids negatively impacted growth performance and antioxidant capacity of nursery pigs. Supplementation of vitamin E and polyphenols improved total antioxidant capacity, especially in pigs fed control diets, but did not restore growth performance.