Alternatives for enrichment of eggs and chicken meat with omega-3 fatty acids

Camelina sativa (L. Crantz) products; an alternative feed ingredient for poultry diets with its nutritional and physiological consequences

Due to increased demand for common feedstuffs such as corn, soybean and fish meals for poultry diets, the search for alternative sources of energy and protein for feed production could help to reduce production costs in the commercial poultry industry. Camelina sativa might be considered a new source of protein, energy and n-3 fatty acids (FA) in poultry diets. The oil content of camelina seeds (CS) is about 35 to 40%. Approximately 50% of this oil is composed of polyunsaturated FA. Moreover, camelina meal (CM) has 16% crude fat. The major n-3 FA of CS and CM is α-linolenic acid (about 30%) which is considered to be nutritionally important. The oil contains other bio-active compounds such as γ-tocopherol, flavonoids and phenolic compounds. Camelina seeds and meal can produce 6258 and 5110 kcal/kg of gross energy, 245-292 and 315-398 g/kg crude protein and 248 and 127 g/kg crude fibre, respectively. However, CS and CM contain 21.77 and 28.08 μmol/g glucosinolates and 12.10 and 12.93 TIU /mg trypsin inhibitors, respectively as anti-nutritional factors (ANFs) that can affect poultry performance adversely. Overall, dietary inclusion of camelina products will supply energy and protein for bird, enhance the antioxidant capacity and lipid stability of poultry products and provide health-promoting n-3 FA and tocopherol rich-foods to humans. However, raw CS contains some ANFs, and its maximum safe level (MSL) is 5% meal or seed, and 2% oil for all type of birds. Hence, it is necessary to establish suitable techniques for removing anti-nutritional factors from CS and increase its MSL in poultry diets.

Feeding of Camelina sativa Seeds to Light-Type Gentile di Puglia Lambs: Effect on Productive Performance and Muscle Fatty Acid Composition

The effect of different amounts of camelina (CAM; Camelina sativa) seeds in lambs of the Gentile di Puglia breed on growth, carcass characteristics, and meat quality was investigated. Up to 70 days of age, twenty-four male lambs (13.0 ± 0.35 kg) were randomly assigned to three isocaloric and isonitrogenous diets. Pelleted total mixed rations (TMR) were created to provide: (1) a control diet (CON), (2) an experimental corn-based diet including 5% camelina (CAM5) seeds, and (3) an experimental corn-based diet containing 10% camelina (CAM10) seeds. The presence of CAM in the diet impacted lamb performance (p < 0.05), according to the results of a growth study. Lambs were slaughtered at the conclusion of the feeding period, and none of the carcass characteristics investigated were significantly affected by dietary treatment, with the exception of brisket and rib weight and carcass lean, which were improved (p < 0.05) in lambs fed the CAM diet. The color of lamb flesh from the Longissimus lumborum muscle was affected by CAM diets (p < 0.05), but the chemical content and physical characteristics did not differ across treatments (p > 0.05). The fatty acid composition of lamb meat in muscle was somewhat regulated by the experimental diets, with CAM feeding improving (p < 0.05) the level of linolenic acid and MUFA while reducing SFA and PUFA. As a result of the current data, it can be stated that camelina seed supplementation may be included in the lamb diet because no negative impacts on productivity, as well as an enhancement in meat quality, have been found.

Evaluating the impact of organic chromium on hepatic phospholipid fatty acid molecular species, transcription of genes associated with lipid metabolism and oxidative status in broiler chickens fed flaxseed

Flaxseed is a rich source of α-linolenic acid (ALA, 18:3 n-3) and can be used to enrich chicken tissues with n-3 fatty acids (FA). However, antinutritional factors in flaxseed compromise the live performance of birds coupled with increased oxidative stress. Chromium (Cr) is a trace element with antioxidant properties. It is hypothesized that Cr supplementation will affect the hepatic total lipid profile, phospholipid n-3 and n-6 FA molecular species, lipid oxidation products, and transcription of genes associated with lipid metabolism in broiler chickens fed flaxseed. Ninety (n = 90), day-old Cornish cross chicks were fed a corn-soybean meal-based diet containing 0% flaxseed (CTR), 10% flaxseed (FLAX), and FLAX + 0.05% organic Cr (FLAXCr) for 42 d. The chicks were kept in 18 pens with 5 chicks per pen. For all response variables, the effect of dietary treatments were compared separately using SAS 9.4. P values were considered significant at ≤0.05. Total lipids, saturated FA, long-chain (≥20C) n-6 FA were reduced while total n-3 FA and long-chain n-3 FA were higher in the liver of FLAX and FLAXCr than CTR (P < 0.05). Hepatic phosphatidylcholine (PC) and phosphatidylethnolamine (PE) n-3 species (36:5, 38:6) were higher in FLAX and FLAXCr compared to CTR (P < 0.05). On the contrary, n-6 species in PC (36:4, 38:4) and PE (38:4) were lower in FLAX and FLAXCr compared to CTR (P < 0.05). Addition of Cr to a flaxseed-containing diet led to an increase in PE 36:4 (P < 0.05). A decrease in the transcription of ELOVL6 gene involved in de novo lipid synthesis was observed in FLAXCr (P = 0.01). An increase in the transcription of genes involved in FA oxidation (ACAA2, ACOX1) was observed in FLAX compared to FLAXCr (P = 0. 05; P = 0.02). A trend for a decrease in the transcription of FADS2 and HMGCS1 was observed in FLAXCr than CTR and FLAX (P = 0.06; 0.08). Transcription of other genes involved in de novo lipid synthesis (FASN, PPARA), FA oxidation (CPT1A, CPT2, ACAA1), and oxidative stress response (GPX1, NQO11, GSTA2, SLC40A1, NFE2L2) were not affected by the diets (P > 0.05). Lipid peroxidation products measured as thiobarbituric acid reactive substances (TBARS) in liver was reduced in FLAXCr than CTR (P < 0.05) and was not different from FLAX (P > 0.05). Serum cholesterol and aspartic aminotransferase were reduced in FLAX and FLAXCr compared to CTR (P < 0.05). The serum glucose level was decreased in FLAX compared to CTR (P < 0.05) and a trend in decrease was noticed in FLAXCr vs. CTR (P = 0.10). Serum TBARS were higher in CTR and FLAXCr compared to FLAX (P < 0.05). In conclusion, flaxseed supplementation enhances total and long-chain n-3 FA while reducing total lipids, saturated, and n-6 FA in the liver. Supplementing Cr along with flaxseed increased n-6 FA species in the hepatic PE and decreased the transcription of genes involved in FA oxidation and lipid synthesis.

Effects of linseed oil supplementation duration on fatty acid profile and fatty acid metabolism-related genes in the muscles of Chinese crested white ducks

Meat rich in polyunsaturated fatty acids is considered beneficial to health. Supplementing the diet with linseed oil promotes the deposition of polyunsaturated fatty acids (PUFAs) in poultry, a conclusion that has been confirmed multiple times in chicken meat. However, fewer studies have focused on the effects of dietary fatty acids on duck meat. Therefore, this study aims to evaluate the effects of the feeding time of a linseed oil diet on duck meat performance and gene expression, including meat quality performance, plasma biochemical indicators, fatty acid profile, and gene expression. For this study, we selected 168 Chinese crested ducks at 28 days old and divided them into three groups, with 56 birds in each group. The linseed oil content in the different treatment groups was as follows: the control group (0% flaxseed oil), the 14d group (2% linseed oil), and the 28d group (2% linseed oil). Ducks in the two experimental groups were fed a linseed oil diet for 28 and 14 days at 28 and 42 days of age, respectively. The results showed that linseed oil had no negative effect on duck performance (slaughter rate, breast muscle weight, and leg muscle weight) or meat quality performance (pH, meat color, drip loss, and shear force) (P > 0.05). The addition of linseed oil in the diet increased plasma total cholesterol and high-density lipoprotein cholesterol levels (P < 0.05), while decreasing triglyceride content (P < 0.05). Furthermore, the supplementation of linseed oil for four weeks affected the composition of muscle fatty acids. Specifically, levels of α-linolenic acid, eicosapentaenoic acid, and docosahexaenoic acid were increased (P < 0.05), while eicosatetraenoic acid content was negatively correlated with flaxseed oil intake (P < 0.05). qRT-PCR analysis further revealed that the expression of FATP1, FABP5, and ELOVL5 genes in the breast muscle, as well as FABP3 and FADS2 genes in the thigh muscle, increased after four weeks of linseed oil supplementation (P < 0.05). However, after two weeks of feeding, CPT1A gene expression inhibited fatty acid deposition, suggesting an increase in fatty acid oxidation (P < 0.05). Overall, the four-week feeding time may be a key factor in promoting the deposition of n-3 PUFAs in duck meat. However, the limitation of this study is that it remains unknown whether longer supplementation time will continue to affect the deposition of n-3 PUFAs. Further experiments are needed to explain how prolonged feeding of linseed oil will affect the meat quality traits and fatty acid profile of duck meat.

Nutritional Strategies to Improve Meat Quality and Composition in the Challenging Conditions of Broiler Production: A Review

Poultry meat is becoming one of the most important animal protein sources for human beings in terms of health benefits, cost, and production efficiency. Effective genetic selection and nutritional programs have dramatically increased meat yield and broiler production efficiency. However, modern practices in broiler production result in unfavorable meat quality and body composition due to a diverse range of challenging conditions, including bacterial and parasitic infection, heat stress, and the consumption of mycotoxin and oxidized oils. Numerous studies have demonstrated that appropriate nutritional interventions have improved the meat quality and body composition of broiler chickens. Modulating nutritional composition [e.g., energy and crude protein (CP) levels] and amino acids (AA) levels has altered the meat quality and body composition of broiler chickens. The supplementation of bioactive compounds, such as vitamins, probiotics, prebiotics, exogenous enzymes, plant polyphenol compounds, and organic acids, has improved meat quality and changed the body composition of broiler chickens.

Effect of rosemary essential oil as nitrite substitute on quality of sausage produced using chicken fed by thymus essential oil and rapeseed oil

The objective was to determine the effect of rosemary essential oil (REO) as nitrite substitute on the physicochemical, microbiological and sensory quality of sausage from broilers fed different levels of thymus essential oil (TEO) and rapeseed oil (RO). Broiler chicks fed TEO (0, 300 and 500 ppm) and RO (1, 3 and 5%) in a 3 × 3 factorial design. Sausages were made from meat of chicken fed TEO (0 and 500 ppm) treated with REO (120 ppm), REO:nitrite (60:60 ppm), nitrite (120 ppm) or without REO and nitrite in a 2 × 4 factorial design. Results showed that TEO increased water holding capacity and pH value and decreased malondialdehyde concentration. RO (1 and 3%) × TEO (500 ppm) group had higher unsaturated to saturated fatty acids ratio in the meat. Results showed that treatments of REO (120 ppm) decreased lipid oxidation and increased pH value of meat. Sausage produced by nitrite (120 ppm) or REO:nitrite (60:60 ppm) had lower total microbial count, lightness but higher redness and yellowness. Based on the results, TEO in chicken feed decreased lipid oxidation of sausages. Furthermore, substitution at least 60 ppm nitrite with REO had more preserving effect on quality of produced sausages.

Effect of seaweed (Ecklonia maxima) on apparent nutrient digestibility, growth performance, and physiological and meat quality parameters in Boschveld cockerels

Despite being touted as a rich source of nutrients and functional bioactive compounds, the amount of brown seaweed (Ecklonia maxima) that can be included in diets of Boschveld indigenous chickens is unknown. This study, therefore, investigated the effect of feeding graded levels of brown seaweed meal (BSM) on apparent nutrient digestibility, growth performance, and physiological and meat quality parameters in Boschveld cockerels. A total of 225, five-wk-old Boschveld cockerels (316.4 ± 23.01 g live weight) were raised on 5 isoenergetic and isonitrogenous experimental diets formulated by incorporating BSM in a standard grower diet at a concentration of 0 (BSM0), 20 (BSM2), 40 (BSM4), 60 (BSM6), and 80 g/kg (BSM8). Feeding graded levels of dietary BSM induced neither quadratic nor linear effects (P > 0.05) on apparent nutrient digestibility, growth performance, hematological parameters, and meat quality characteristics in Boschveld cockerels. However, it resulted in linear increases for overall feed intake (R² = 0.397; P = 0.021), ceca weight (R² = 0.417; P = 0.013), duodenum length (R² = 0.537; P = 0.04), and small intestine length (R² = 0.305; P = 0.041). Negative quadratic responses were recorded for alanine aminotransferase (R² = 0.530; P = 0.0009) and ileum length (R² = 0.457; P = 0.045) as BSM levels increased. In conclusion, dietary inclusion of BSM improved feed intake and some internal organ sizes, altered alanine transaminase levels, but had no significant effect on apparent nutrient digestibility, growth performance, and carcass and meat quality attributes of Boschveld indigenous cockerels.

The effect of astaxanthin and lycopene on the content of fatty acids in the yolks of chicken eggs under different storage regimes

The level of consumers’ satisfaction with the quality of edible chicken eggs is determined, in particular, by the attractive appearance of the yolks and their content of biologically active substances that have functional properties. Such compounds include carotenoids astaxanthin and lycopene, which can be deposited in the yolks, provide their pigmentation, and as powerful antioxidants, affect the stability of the fatty acid composition of lipids during egg storage. The aim This study aimed mine the effect of supplements of oil extracts of astaxanthin (10, 20, and 30 mg/kg of feed) or lycopene (20, 40, and 60 mg/kg of feed) on the Dion of young hens on the fatty acid composition of the yolks during eggs storage in temperature conditions 4 ±0.5 ℃ and 12 ±0.5 ℃ for 30 days. The experiment used 45 High-Line W36 crossbred laying hens at 24 weeks of age. It was found that the storage temperature of eggs (4 ±0.5 ℃ and 12 ±0.5 ℃) equally affected the fatty acid composition of lipids of egg yolks obtained from laying hens fed lycopene supplements in doses of 20, 40, and 60 mg/kg or astaxanthin in doses of 10, 20 and 30 mg/kg of feed for 30 days. Doses of lycopene from 20 to 60 mg/kg or astaxanthin from 10 to 30 mg/kg in the diet of laying hens contributed to a decrease in egg yolks at both storage temperatures of ω6 PUFA particles: Eicosatetraenoic and 6.9, 12-okadekatrienic acids until their complete disappearance. The addition of astaxanthin to the diet of laying hens reduced and stabilized the ratio of ω3/ω6 PUFA in yolks during egg storage to a greater extent than the addition of lycopene. Storage of lycopene or astaxanthin-enriched edible chicken eggs at 4 ±0.5 °C and 12 ±0.5 °C for 30 days can be used to correct the fatty acid profile of yolk lipids.

Partial replacement of soybean meal with Chlorella vulgaris in broiler diets influences performance and improves breast meat quality and fatty acid composition

Alternative feed ingredients, such as microalgae, may be more sustainable in comparison to conventional feedstuffs that need large amounts of arable land and are often imported. This study evaluates the effects of Chlorella vulgaris various inclusion levels in the diet of broiler chickens on performance, carcass yield, organ measurements, breast meat quality, fatty acids profile, and antioxidant capacity. A total of two hundred forty 5 d old male Ross 308 broilers were randomly allotted to 4 groups (6 replicates of 10 birds each). Each group received either a control diet or a diet where soybean meal was replaced with 10% (CV10%), 15% (CV15%), or 20% C. vulgaris for 40 d. Performance parameters, carcass and meat traits were evaluated. Compared to the control group, birds supplemented with C. vulgaris (15% and 20%) had lower body weight, weight gain, and feed intake (P < 0.0001), whereas no differences were observed between the control and CV10% groups (P > 0.05). Feed conversion ratio did not differ between control and CV groups. Diets containing C. vulgaris significantly increased ileal digesta viscosity, weight and size of several gastrointestinal compartments, as well as breast muscle yield (P < 0.0001). Incorporation of C. vulgaris resulted in yellower breast muscle (P < 0.0001), with significantly increased chlorophyll a (P < 0.05), chlorophyll b, and total carotenoids contents (P < 0.0001). Inclusion of C. vulgaris decreased bacterial count in meat samples in comparison to controls (P < 0.0001). A 20% C. vulgaris inclusion resulted in higher water holding capacity (P < 0.05) and lower cooking loss (P < 0.05). As dietary C. vulgaris increased, concentrations of DHA + EPA (P < 0.05) and n-3 PUFA (P < 0.0001) increased in breast meat, while the n-6/n-3 PUFA ratio decreased (P < 0.0001). Sensory analysis showed that breast meat from the CV10% group had the highest acceptance score. Overall, dietary concentrations of C. vulgaris of up to 20% improve breast meat quality, whereas 10% of C. vulgaris inclusion is recommended.

Supplementation of Broiler Chicken Feed Mixtures with Micronised Oilseeds and the Effects on Nutrient Contents and Mineral Profiles of Meat and Some Organs, Carcass Composition Parameters, and Health Status

In this study, we included 15% doses of infrared-irradiated camelina, flax, and sunflower seeds in the diets of broiler chickens (grower and finisher) and focused on assessing the effects on the production traits, selected slaughter analysis parameters, nutrients, and minerals in breast and drumstick meat and some organs, i.e., liver, proventriculus, and heart. In total, 200 one-day-old broiler chickens were assigned randomly to four treatments with five replicate cages of 10 broiler chickens per cage (five females and five males). The experiment lasted 6 weeks. In the group of broiler chickens in which diets were supplemented with micronised camelina and flax seeds, there was an increase in (p < 0.05) breast, thigh, and drumstick weight and a decrease (p < 0.05) in the abdominal fat of the carcasses. The oilseed treatments reduced the ether extract content and the calorific value in the breast and drumstick muscles and organs. The flax seeds contributed to an increase in the contents of Ca (breast muscle and liver), Cu (breast muscle and proventriculus), and Fe (drumstick muscle and heart). Likewise, some blood parameters were influenced by supplementation with infrared-irradiated camelina and flax seeds, for example, there was a decrease in the haemoglobin level and the mean corpuscular haemoglobin concentration (p < 0.05). The oilseed treatments also modified the contents of Fe and Ca in the blood plasma of broiler chickens (p < 0.05). It may be concluded that infrared-irradiated camelina, flax, and sunflower seeds can be regarded as good diet components exerting positive effects on the dietary value of poultry meat and organs used in dietetics.

Fatty Acids Profile and Healthy Lipids Indices of Native Mexican Guajolote Meat Treated to Two Heat Treatments

Simple Summary

The native guajolote meat is an important dietary source of proteins of high biological value for the rural population of Mexico. However, many of its quality characteristics are still unknown. Therefore, the fatty acids (FAs) profile and nutritional indices of breast and leg meat of native guajolote subjected to two heat treatments (boiled and baked) were evaluated. The heat treatments increased the concentration of saturated (SFA) and monounsaturated FA (MUFA) in the meat; in contrast, the concentration of polyunsaturated FA (PUFA) decreased. Likewise, the dietary FA index and the atherogenic index increased in guajolote meat from the effect of the heat treatments, while the essential and hypercholesterolemic FA indices decreased. Based on the results obtained, heat treatments increase the content of SFA and MUFA in breast and leg meat of native guajolote. Baking is less favorable for both types of muscle.

Abstract

Meat is a complex food with a structured nutritional composition that makes it an essential component of the human diet. In particular, the meat of native guajolote that is traditionally raised in natural conditions is an important dietary source of proteins of high biological value for the rural population of Mexico. The study aimed to evaluate fatty acids (FAs) profile and nutritional indices of breast and leg meat of native guajolote subjected to two heat treatments. For the study, a total of sixty muscle samples (30 breast meat and 30 leg meat) from adult male native guajolotes were used. The FA profile and nutritional indices were evaluated in raw meat (control) and meat subjected to two heat treatments (boiled and baked). The heat treatments, independently of the type of muscle, increased (p ≤ 0.05) the concentration of saturated (SFA) and monounsaturated FA (MUFA); in contrast, polyunsaturated FA (PUFA) decreased. Likewise, the dietary FA index, which has a negative hypercholesterolemic effect, and the atherogenic index increased in guajolote meat from the effect of the heat treatments, while the essential and undesirable hypercholesterolemic FA indices decreased. In conclusion, heat treatments increase the content of SFA and MUFAs in breast and leg meat of native guajolote. Boiling or baking the meat deteriorates PUFAs but increases the nutritional indices. The present investigation would provide valuable information for the guajolote meat product processing.

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.

Antioxidant effects of seaweeds and their active compounds on animal health and production - A Review

Natural antioxidants applied as feed additives can improve not only animals’ health and overall performance but also increase their resistance to environmental stress such as heat stress, bad housing conditions, diseases, etc. Marine organisms, for example seaweeds – red, brown, and green macroalgae contain a plethora of biologically active substances, including phenolic compounds, polysaccharides, pigments, vitamins, micro- and macroelements, and proteins known for their antioxidant activity, which can help in the maintenance of appropriate redox status in animals and show pleiotropic effects for enhancing good health, and productivity. The dysregulated production of free radicals is a marked characteristic of several clinical conditions, and antioxidant machinery plays a pivotal role in scavenging the excessive free radicals, thereby preventing and treating infections in animals. Supplementation of seaweeds to animal diet can boost antioxidant activity, immunity, and the gut environment. Dietary supplementation of seaweeds can also enhance meat quality due to the deposition of marine-derived antioxidant components in muscles. The use of natural antioxidants in the meat industry is a practical approach to minimize or prevent lipid oxidation. However, overconsumption of seaweeds, especially brown macroalgae, should be avoided because of their high iodine content. An important point to consider when including seaweeds in animal feed is their variable composition which depends on the species, habitat, location, harvest time, growing conditions such as nutrient concentration in water, light intensity, temperature, etc. This review highlights the beneficial applications of seaweeds and their extracted compounds, which have antioxidant properties as feed additives and impact animal health and production.

The effect of stocking rate and supplementary selenium on the fatty acid composition and subsequent peroxidisability of poultry muscle tissues

Selenium (Se) plays a crucial role in protecting biological materials from oxidative damage through the action of the selenoprotein glutathione peroxidase (GSH-Px), and the effectiveness of this protection is often dependent upon Se supply. Recent evidence has indicated that GSH-Px mRNA expression can be upregulated in response to potential oxidative damage risk, and that this upregulation is independent of Se supply. The current study aimed to determine the effect of Se supplementation, stocking rate and tissue fatty acid profile on GSH-Px activity in breast and thigh tissue of commercial broilers. A total of 168 Ross 308 broiler chicks were enrolled onto the study. Prior to enrolment, birds were brooded as a single group and received a starter diet containing no additional Se. The study was a 2 × 2 factorial design comprising of two levels of dietary Se (high Se, 0.5 mg/kg total Se, low Se background Se only), and two stocking rates (high, 30 kg/m², and low, 15 kg/m²). At 15 days of age, birds were blocked by live weight and randomly allocated to one of the four treatments, with six pen replicates per treatment. At 42 days of age, one bird was randomly selected from each pen replicate, euthanased and breast and thigh tissue harvested. GSH-Px activity, thiobarbituric acid reactive substances (TBARS), and fatty acid (FA) content of these tissues were determined. There was no effect (P > 0.05) of stocking rate on GSH-Px activity or TBARS. GSH-Px activity did not differ between tissue types but was greater in high Se birds (P < 0.001) compared to low Se. TBARS concentrations were greater in thigh tissue (P < 0.001), and these thigh concentrations were greater in high Se birds (P < 0.05). There were marked differences between breast and thigh tissue in most FAs (P < 0.001), with breast generally containing greater proportions of polyunsaturated FA, so that breast tissue had a higher (P < 0.001) peroxidisability index (PI) than thigh. A positive correlation between GSH-Px activity and PI in the thigh tissue of high Se birds (Pearson Correlation 0.668; P = 0.025) may indicate that increasing susceptibility to peroxidisation in lipid-rich tissues may also upregulate GSH-Px activity in Se-replete birds. This study suggests that ensuring adequate dietary selenium could be a useful tool to mitigate adverse effects on meat quality caused by oxidation, particularly in lipid-rich meat.

Camelina (Camelina sativa (L.) Crantz) as Feedstuffs in Meat Type Poultry Diet: A Source of Protein and n-3 Fatty Acids

Simple Summary

One of the main problems in poultry production is to find more sustainable feed protein sources, other than the most widely used soya bean meal. An alternative protein source could be the underexploited oilseed crop camelina (Camelina sativa (L.) Crantz), which is mostly grown for biodiesel production, but is also characterized by disease and pest resistance, tolerance to cold weather, drought and low fertility soil. This review presents the nutritive value of camelina seeds, oil and cake (a by-product of biodiesel production), and their effect on the growth performance and fatty acid profile of muscles and liver in meat type poultry. The research results indicated that supplementation of poultry diets with camelina feedstuffs beneficially modified the fatty acid composition of meat and liver. The ratio of n-6/n-3 polyunsaturated fatty acids (PUFA) decreased, whereas the content of α-linolenic and long-chain n-3 PUFA increased in poultry tissues.

Abstract

Camelina seed or seed processing derivatives, i.e., cake, are cheap alternative protein feed ingredients for meat type poultry. Camelina is an oilseed crop containing 36.8% oil in seeds, while in the cake the oil content accounts for 6.4–22.7%. If compared with other Brassicaceae family plants, camelina is distinguished by a unique fatty acid composition, because the content of α-linolenic fatty acid (C18:3n-3; ALA) varies from 25.9 to 36.7% of total fatty acids. The total tocopherol content in camelina oil and cake are, respectively, 751–900 and 687 mg/kg. Addition of camelina to poultry nutrition increases the amount of n-3 polyunsaturated fatty acids (PUFA) in poultry meat and liver. The content of ALA in chicken muscles increases by 1.3–4.4, 2.4–2.9 and 2.3–7.2 times after supplementing chicken diets with, respectively, camelina cake (8–24%), seed (10%), and oil (2.5–6.9%) in comparison with the control group. Camelina cake (5–25%), seed (10%) and oil (2.5–4%) inclusion in chicken diets results in 1.5–3.9 times higher total n-3 PUFA content in muscles and liver. Meanwhile, supplementation of chicken diets with camelina oil (4–6.9%), seed (5–10%) and cake (5–25%) results in, respectively, a 1.8–8.4, 1.6–1.9 and 1.3–2.9 times lower n-6/n-3 PUFA ratio in muscles, and 3.29 times lower n-6/n-3 PUFA ratio in the liver. After inclusion of different amounts of camelina cake in chicken diets, a healthy for human nutrition n-6/n-3 PUFA ratio from 1.6 to 2.9 was found in chicken muscles.

Enriching laying hens eggs by feeding diets with different fatty acid composition and antioxidants

The current study was conducted to evaluate egg quality, egg yolk fatty acids, health-related indices and antioxidants from laying hens' eggs fed different combined vegetable by-products, rich in fatty acids and antioxidants. One hundred twenty 50 weeks-old Tetra SL laying hens were divided into three groups. They were given daily a standard diet (Control, C), a diet containing 9% rapeseed meal with 3% grapeseed meal (T1 diet), or a diet containing 9% flaxseed meal and 3% sea buckthorn meal (T2 diet). Hen production performances, egg quality, egg yolk fatty acids total polyphenols content and antioxidant capacity were determined. The T1 diet significantly reduced the egg yolk content of palmitic acid from 76.615 mg (C) to 46.843 mg (T1) and that of oleic acid from 788.13 mg (C) to 682.83 mg (T1). Feeding flaxseed and sea buckthorn meals significantly increased the egg yolk content of α-linolenic acid in T2 yolks (35.297 mg) compared with C yolks (4.752 mg) and that of docosahexaenoic acid (DHA) from 16.282 mg (C) to 74.918 mg (T2). The atherogenicity indices (AI) were not significantly affected, whereas the thrombogenicity indices (TI) decreased significantly (p < 0.0007) from 0.72 (C) to 0.60 (T1) and 0.66 (T2), respectively. Adding this combination of meals to the hens' diets, increased the total polyphenol content and antioxidant capacity in T1 and T2 eggs compared to C eggs. The significant enrichment of eggs with n-3 fatty acids and antioxidant capacity, as well on the health-related indices especially from T2 eggs, represents a potential functional feed ingredient in poultry feeding, to obtain eggs as functional food.

Microalgal-based feed: promising alternative feedstocks for livestock and poultry production

There is an immediate need to identify alternative sources of high-nutrient feedstocks for domestic livestock production and poultry, not only to support growing food demands but also to produce microalgae-source functional foods with multiple health benefits. Various species of microalgae and cyanobacteria are used to supplement existing feedstocks. In this review, microalgae have been defined as a potential feedstock for domestic animals due to their abundance of proteins, carbohydrates, lipids, minerals, vitamins, and other high-value products. Additionally, the positive physiological effects on products of animals fed with microalgal biomass have been compiled and recommendations are listed to enhance the assimilation of biomolecules in ruminant and nonruminant animals, which possess differing digestive systems. Furthermore, the role of microalgae as prebiotics is also discussed. With regards to large scale cultivation of microalgae for use as feed, many economic trade-offs must be considered such as the selection of strains with desired nutritional properties, cultivation systems, and steps for downstream processing. These factors are highlighted with further investigations needed to reduce the overall costs of cultivation. Finally, this review outlines the pros and cons of utilizing microalgae as a supplementary feedstock for poultry and cattle, existing cultivation strategies, and the economics of large-scale microalgal production.

Docosahexaenoic acid (22:6 n-3)-rich microalgae along with methionine supplementation in broiler chickens: effects on production performance, breast muscle quality attributes, lipid profile, and incidence of white striping and myopathy

The effect of docosahexaenoic acid (DHA, 22:6 n-3)-rich microalgae and methionine (Met) supplementation on production performance, incidence of breast muscle white striping (WS), and pathology, lipid profile, and meat quality aspects in broiler chickens was investigated. The hypothesis tested was that feeding Met and n-3 fatty acid (FA)-rich diet enhances muscle n-3 FA content and meat quality while attenuating breast muscle WS and myopathy in broiler chickens. One hundred and forty four (n = 144) 10-day-old Cornish cross chicks were fed a corn-soybean meal-based diet containing 0% microalgae (control), 2% microalgae (diet 1), and diet 1 + 100% more National Research Council requirement of Met (diet 2) up to day 42 of growth. All diets were isocaloric and isonitrogenous. The chicks were kept in 6 pens with 8 chicks per replicate pen. Feed consumption and feed efficiency were calculated on day 21 and 42. On day 43, 3 chicks per pen (n = 18/treatment) were euthanized. The breast muscle (pectoralis major) was visually scored for muscle WS (1 = no striping, 2 = mild, 3 = severe) and was subjected to histopathology. Breast muscle lipid profile (total lipids, FA composition, cholesterol, lipid oxidation products), quality (moisture, color, drip loss, shear force, cook loss, pH), and chemical characterization (protein, minerals) were recorded. A one-way analysis of variance was carried out with diet as the main factor and significance was set at P < 0.05. The incidence of muscle WS was lower (P < 0.02) for control vs. diet 2 and a trend for reduction in WS was observed in birds fed diet 1 vs. control (P = 0.09). Histopathological changes consisted of floccular or vacuolar degeneration, fibrosis, lipidosis, interstitial inflammation, and lysis of fibers, and were minimal in diet 2 when compared to control (P < 0.05). The total lipid content was lowest in birds fed diet 1 (P < 0.05). Total n-3 and total long chain (≥20C) n-3 FA were highest in the breast muscle of diet 2 birds (P < 0.05). Muscle drip loss and shear force were highest in diet 2 (P < 0.05). Meat color (a∗, redness) was reduced (P < 0.05) and a trend for reduction in b∗ (yellowness) was observed in diet 2 (P = 0.07). No effect of diet on body weight gain, feed efficiency, breast muscle yield, pH, moisture, lipid oxidation products, cook loss, minerals (Ca, P, Mg, Na), cholesterol, or protein content was observed (P > 0.05). The results demonstrated a significant effect of DHA-rich microalgae along with Met supplementation in reducing the incidence of breast muscle striping and myopathy, while enriching meat with n-3 FA. However, inclusion of Met in microalgae-based diets could influence meat tenderness and color.

Seaweeds, Intact and Processed, as a Valuable Component of Poultry Feeds

Poultry production is an important area of the agricultural economy. Nowadays, there is an interest in novel sources of feed additives that will improve production performance and poultry health. As an easily available and renewable biomass rich in biologically active compounds, seaweeds can meet this demand. Different forms of seaweeds–seaweed powder from naturally occurring biomass, cultivated or waste biomass, extracted compounds, post-extraction residues or liquid extracts–may be used in poultry feeding. Inclusion of this unconventional material in the poultry nutrition can positively influence the poultry performance along with its health and enrich poultry products with active compounds, such as micro- and macroelements, polyunsaturated fatty acids and pigments. Seaweeds also reduce lipids and cholesterol in eggs. Moreover, due to their unique properties, they can serve as an alternative to antibiotic growth promoters. This review presents the latest developments in the use of seaweeds in poultry nutrition, as well as its limitations.

Effect of full-fat sunflower or flaxseed seeds dietary inclusion on performance, egg yolk fatty acid profile and egg quality in laying hens

A study was conducted to evaluate the effect of the dietary inclusion of full-fat flaxseed or full-fat sunflower seeds on performance parameters, egg quality parameters and egg yolk fatty acid profile in laying hens. A total of 150 Babcock Brown hens at 27 weeks of age were distributed in 3 experimental treatments, as follows: T1, control; T2, diet containing 13.5% full-fat whole flaxseed seeds; and T3, diet containing 13.5% full-fat ground sunflower seeds. Feed and water were provided ad libitum and the experiment lasted for 8 weeks. No significant differences were found on egg quality parameters, but total egg production and rate of lay were significantly (P < 0.05) lower in the group receiving sunflower seeds compared with the control, and significant differences (P < 0.05) in egg yolk saturated, monounsaturated, polyunsaturated, omega-6 (n-6) and omega-3 (n-3) fatty acids were observed, as well as in the n-6:n-3 ratio. The results show that the dietary inclusion of 13.5% flaxseed full-fat seeds significantly increases the n-3 polyunsaturated fatty acid (PUFA) content in the eggs and lowers the n-6:n-3 ratio without affecting performance parameters. Inclusion of full-fat sunflower seeds increases the n-6 PUFA content but affects total egg production and rate of lay. Further studies are needed to determine the level of inclusion of full-fat sunflower seeds that does not affect performance.

Inclusion of Camelina, Flax, and Sunflower Seeds in the Diets for Broiler Chickens: Apparent Digestibility of Nutrients, Growth Performance, Health Status, and Carcass and Meat Quality Traits

Simple Summary

The presented results were obtained in a scientific trial, in which the addition of camelina, flax, and sunflower seeds to Ross 308 broiler diets was tested in terms of improvement of production efficiency, health status parameters, and quality of poultry meat. The results of the research showed that the tested full-fat seeds can be considered good dietary ingredients with a positive effect on the poultry production process and, consequently, on the dietary value of poultry meat.

Abstract

The study determined the effect of the addition of 15% of camelina, flax, and sunflower seeds to iso-caloric and iso-nitrogenous diets for broiler chickens during 21–42 days of age on the nutrient digestibility, production traits, slaughter analysis parameters, hematological indices, blood mineral elements, and dietary value of breast and drumstick meat. Two hundred one-day-old broiler chickens were assigned to four groups (treatments) with five replicates (10 birds per cage, 5 females and 5 males). The experiment lasted 6 weeks. Broiler chickens receiving diets supplemented with camelina and flax seeds exhibited an increase (p < 0.05) in average body weight and a decrease (p < 0.05) in the ether extract content and energy digestibility of the diets. Moreover, the best carcass quality with a high proportion of muscles and low abdominal fat content (p < 0.05) was noted in broilers fed flax- and sunflower-enriched diets. The treatments with the oil seeds reduced the ether extract content and the calorific value of breast and drumstick muscles. The flax seeds contributed to an increase in the Fe content in drumstick muscles. Additionally, some blood parameters were influenced by the flax seed supplementation, e.g., the level of hemoglobin declined (p < 0.05) and the iron level in plasma increased (p < 0.05). It can be concluded that the camelina, flax, and sunflower seeds can be regarded as good dietary components with positive effects on the dietary value of poultry meat.

Influence of dietary plant fats and antioxidant supplementations on performance, apparent metabolizable energy and protein digestibility, lipid oxidation and fatty acid composition of meat in broiler chicken

This study aimed to evaluate the effects of dietary different antioxidants and plant oils on performance, apparent metabolizable energy and protein digestibility, meat quality and meat fatty acid composition of broiler chickens. In all, 480 male broiler chicks of 1‐day old were assigned in a completely randomized design with factorial arrangement 2 × 5 (plant oil sources [soybean and rapeseed oils] and antioxidant sources [vitamin E, Thyme, Rosemary and Satureja essential oils] furthermore control treatment without antioxidant). The results indicated that at 1–42 d of age, growth performance and carcass yield of birds were not influenced by dietary plant oils and antioxidant supplementations. Dietary Thyme essential oil (300 mg/kg) resulted in an increase in crude protein digestibility and birds fed on diets without antioxidant showed increase in the apparent metabolizable energy (p < .01). Birds receiving the combination of soybean oil with Rosemary essential oil had lowest malondialdehyde concentration in comparison to birds receiving other treatments (p < .05) in the drumstick meat. Also, birds receiving the combination of soybean oil with vitamin E had lowest malondialdehyde concentration in comparison to birds receiving other treatments (p < .05) in the breast meat. The results indicated that treatments did not influence water holding capacity of meat. Also, dietary rapeseed oil and Thyme essential oil supplementations, separately, decreased saturated fatty acid (p < .01) and increased unsaturated fatty acid and unsaturated to saturated fatty acids ratio (p < .01) of drumstick meat tissue in broiler chicken (p < .01). In conclusion, dietary rapeseed oil and Thyme essential oil increased in n‐3 polyunsaturated fatty acids in the drumstick meat (p < .01) and a combination of dietary soybean oil, Rosemary essential oil and vitamin E decreased the lipid oxidation in the meat of broiler chickens (p < .05).

Egg quality, fatty-acid composition and gastrointestinal morphology of layer hens fed whole flaxseed with enzyme supplementation

1. Flaxseed is a rich source of α-linolenic acid (ALA, 18:3 n-3). Feeding flaxseed to hens can increase n-3 fatty acids (FA) in eggs. However, non-starch polysaccharides (NSP) in flaxseed decrease nutrient digestibility and can have a negative impact on egg n-3 FA incorporation. Addition of carbohydrase enzymes to flaxseed-based diets can decrease the anti-nutritive effects of NSP. 2. An experiment was conducted to investigate the effect of enzyme supplementation on FA composition and gastrointestinal morphology in hens fed flaxseed. A total of seventy-two, 51-week old brown layer hens were randomly assigned to one of the four dietary treatments (six replicates with three hens per replicate): corn-soybean based diet containing 0% flax (Control), 10% flax (Flax), Flax+0.05% enzyme (Flax+E1), or Flax+0.1% enzyme (Flax+E2) in a 120-day feeding trial. 3. Egg weight was highest in hens fed Flax+E1 (P < 0.05). Yolk weight was higher in Flax+E1 compared with the control and Flax+E2 and was not different from Flax treatment. ALA and total n-3 FA was highest in eggs from Flax+E2 hens (P < 0.05). Addition of enzyme has no effect of on docosahexaenoic acid (DHA), total long chain (>20-C FA), or n-6:n-3 FA ratio in eggs from hens fed flaxseed-based diets (P > 0.05). Over nine-fold increase in hepatic ALA was observed in the liver of hens fed flaxseed-based diets when compared with the control diet (P < 0.0001). No effect of enzyme supplementation was observed on liver ALA, DHA or long chain n-3 FA (P > 0.05). Enzyme supplementation reduced arachidonic acid, total n-6 and LC n-6 FA in liver tissue from hens fed flaxseed-based diets (P > 0.05). 4. Villi height and width was higher in the duodenum and jejunum of hens fed flax-based diets compared to the control (P < 0.05). Enzyme supplementation led to an increase in villi width in jejunum (P < 0.05) in hens fed Flax+E2 (P < 0.05). No effect of diet was observed in the crypt depth and villi height:crypt depth ratio in the jejunum (P > 0.05). 5. It was concluded that enzyme supplementation enhanced total n-3 FA deposition in eggs and liver and influence gastrointestinal morphology in layer hens fed flaxseed.

Heterotrophic Aurantiochytrium sp. supplementation to layer diets sustainably increases the omega-3 concentration of eggs

1. The consumption of adequate amounts of the long-chain polyunsaturated omega-3 fatty acids (n-3 LC-PUFA) has been associated with beneficial effects on human health. Eggs are commonly consumed worldwide, and their omega-3 content can be easily altered by changing the diets of laying hens and so represent an important target for enrichment. 2. In this study, the effect of supplementing laying hens with DHA-rich, Aurantiochytrium limacinum at three different inclusion levels was investigated over a 24-week period. 3. Significant increases in egg DHA concentrations were observed after four weeks and were maintained for the duration of the 24-week study. The supplemented eggs in the current study had a DHA content of 82, 101, and 129 mg/yolk when supplemented with 0.25%, 0.5% and 1% treatments, respectively, which meets the EU criteria to be considered 'high in omega-3'. 4. Using the sustainably grown protist Aurantiochytrium limacinum to supplement layer diets increased the egg DHA concentration and decreased the n-6/n-3 ratio, improving the nutritional value of the eggs for human consumers.

Whole-Life or Fattening Period Only Broiler Feeding Strategies Achieve Similar Levels of Omega-3 Fatty Acid Enrichment Using the DHA-Rich Protist, Aurantiochytrium limacinum

The fatty acid composition of broiler chicken tissues can be increased by adding omega-3 rich ingredients to their diets. The purpose of this study was to compare the levels of tissue enrichment observed following the supplementation of broilers with the docosahexaenoic acid (DHA)-rich protist, Aurantiochytrium limacinum (AURA) for their whole life (42 days) or for the final 21-day fattening period. Day-old chicks (n = 350) were distributed among 35 pens (10 birds per pen) with each pen randomly assigned to one of five treatments: Control; 0.5% AURA from day 0-42; 1% AURA from day 0-42; 0.5% AURA from day 21-42; 1% AURA from day 21-42. Production parameters were recorded over the course of the study and the fatty acid profile of the breast, thigh, liver, kidney and skin with adhering fat was quantified at the end of the feeding period. The level of supplementation had a significant impact on the degree of omega-3 tissue enrichment, however, no differences were observed when the same dose was provided for 21 or 42 days. These results indicate that supplementation with AURA for a period of 21 days does not negatively affect broiler productivity and is the most efficient strategy to increase the nutritional value of broiler products.

Apparent metabolizable energy values ofn-6 andn-3 rich lipid sources for laying hens

The objective of this research was to evaluate the nitrogen-corrected apparent metabolizable energy (AMEn) balance of the following lipid sources: soybean oil, sunflower oil, linseed oil, and fish oil. Two hundred eighty 24-wk-old laying hens of the Hysex White were used. The experimental diets consisted of a basal diet (reference group), basal diet + 10% soybean oil addition (group 1), basal diet + 10% sunflower oil addition (group 2), basal diet + 10% linseed oil addition (group 3), and basal diet + 10% fish oil addition (group 4), distributed in a completely randomized design with seven replicates and eight birds per experimental unit. The metabolic assay was performed by the total excreta collection method. The AMEn values found in the natural material were 9 334 kcal kg−1for soybean oil, 10 533 kcal kg−1for sunflower oil, 10 928 kcal kg−1for linseed oil, and 9 005 kcal kg−1for fish oil. The AMEn were different among the lipid sources. Sunflower oil and linseed oil had higher AMEn compared with soybean oil and fish oil (P < 0.05). The AMEn of the lipid sources of plant origin had higher values than the gross energy. The fatty acid profile of each lipid source was presented in this work. Thus, it is important to have individual nutritional information for each type of oil for laying hens, making it possible to formulate more appropriate and accurate feed.

Effects of diets containing linseed oil or lard and supplemented with pumpkin seeds on oxidative status, blood serum metabolites, growth performance, and meat quality of naked neck chickens

This study investigates the effect of two dietary fats, namely linseed oil (LO) and lard (LF), and supplementation with pumpkin seeds (PS) on the performance, oxidative status, and blood serum metabolites of broilers, along with the composition, oxidative stability, and fatty acid (FA) profile of broiler meat. Ninety-six 64-d-old naked neck chickens were randomly distributed into four groups of 24 chickens each (8 chickens per cage, three cages per treatment) and fed a LO diet, a LO diet supplemented with 50 g PS kg−1, a LF diet, and a LF diet supplemented with 50 g PS kg−1. The antioxidant system is increased and reactive oxygen species decreased in chickens fed PS diets. Glycemia and cholesterol levels were significantly lower in the chickens fed PS diets than in those given diets without supplementation; the cholesterol levels were also significantly lower in the chickens fed LO diets than those fed LF diets. However, the LO diet affected the fresh meat quality by decreasing pH values of the meat at 24 h after slaughter. Adding PS to the LO diet improved the oxidative stability of the muscle at day 3 of refrigerated storage. The use of LO instead of LF favourably modulates the FA profile of meat, by increasing both linoleic and α-linolenic acid content and reducing the n-6/n-3 polyunsaturated FA ratio, atherogenic and thrombogenic index.

Review on docosahexaenoic acid in poultry and swine nutrition: Consequence of enriched animal products on performance and health characteristics

Omega-3 polyunsaturated fatty acids (n-3 PUFA) are linked to a variety of health benefits against human disorders and disease. However, the typical western diet is generally low in n-3 PUFA and high in n-6 PUFA, suggesting that the recommended intake of these essential fatty acids is seldom achieved. Therefore, dietary enrichment of animal meat and eggs with n-3 PUFA could help increase consumption of these fatty acids. Fish oils and microalgae (MA) are rich sources of long chain n-3 PUFA, specifically eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Feeding these marine products has been shown to increase DHA content of tissues and yolk, however, this may also lead to an increased requirement for anti-oxidants to prevent oxidative deterioration and associated negative sensory attributes. Nonetheless, increased DHA has been linked to promising results in animal growth, fertility, immunity and bone strength in both pigs and poultry. These findings suggest that feeding DHA-rich ingredients to mono-gastric can enrich human diets as well as providing additional benefits to the animal.

Performance and tissue fatty acid profile of broiler chickens and laying hens fed hemp oil and HempOmegaTM

This study was conducted to determine the effects of hemp oil (HO) and HempOmega (HΩ), an equivalent product to HO, on performance and tissue fatty acid profile of layers and broiler chickens in two separate experiments. In the first experiment, forty 19-wk old Lohmann white laying hens were randomized to 1 of 5 dietary treatments, either a control diet or a control diet supplemented with 4 or 8% hemp oil provided by HO or HΩ, for a period of 6 wk (n = 8/diet). In experiment 2, 150-day-old mixed-sex (75 male; 75 female) Ross 308 chicks were randomly allocated into 5 dietary treatments, a control diet or a control diet supplemented with either 3 or 6% hemp oil provided by HO or HΩ, each with six replicates of 5 chicks for a 21-d feeding period. Performance of layers and broilers was not affected by dietary treatments. Animals provided with either HO or HΩ diets had greater total n-3 polyunsaturated fatty acids (PUFAs), alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), docosapentaenoic acid (DPA), and docosahexaenoic acid (DHA) in egg yolks, thighs, and breasts compared to the control diet (P < 0.01), and monounsaturated fatty acids (MUFAs) content of egg yolks and thighs decreased (P < 0.05). The levels of total n-6 PUFAs, linoleic acid (LA), or arachidonic acid (ARA) of the egg yolk and meat were generally not affected by dietary supplementation with HO or HΩ, but gamma-linolenic acid (GLA) was notably increased (P < 0.01). The current data show that inclusion of hemp oil up to 8% in layer diets and 6% in broiler diets provided by HO or HΩ does not negatively affect overall performance of birds and results in the enrichment of n-3 PUFAs and GLA in eggs and meat.

In ovo exposure to omega-3 fatty acids does not enhance omega-3 long-chain polyunsaturated fatty acid metabolism in broiler chickens

The content of omega-3 long-chain polyunsaturated fatty acids (n-3 LCPUFA) in chicken meat can be boosted by feeding broilers a diet containing α-linolenic acid (ALA, from flaxseed oil), some of which is converted by hepatic enzymes to n-3 LCPUFA. However, most of the accumulated n-3 polyunsaturated fatty acid (PUFA) in meat tissues is still in the form of ALA. Despite this, the levels of chicken diets are being enhanced by the inclusion of vegetable and marine sources of omega-3 fats. This study investigated whether the capacity of chicken for n-3 LCPUFA accumulation could be enhanced or inhibited by exposure to an increased supply of ALA or n-3 LCPUFA in ovo. Breeder hens were fed either flaxseed oil (High-ALA), fish oil (high n-3 LCPUFA) or tallow- (low n-3 PUFA, Control) based diets. The newly hatched chicks in each group were fed either the High-ALA or the Control diets until harvest at 42 days' post-hatch. The n-3 PUFA content of egg yolk and day-old chick meat closely matched the n-3 PUFA composition of the maternal diet. In contrast, the n-3 PUFA composition of breast and leg meat tissues of the 42-day-old offspring closely matched the diet fed post-hatch, with no significant effect of maternal diet. Indeed, there was an inhibition of n-3 LCPUFA accumulation in meat of the broilers from the maternal Fish-Oil diet group when fed the post-hatch High-ALA diet. Therefore, this approach is not valid to elevate n-3 LCPUFA in chicken meat.

Impact of dietary precursor ALA versus preformed DHA on fatty acid profiles of eggs, liver and adipose tissue and expression of genes associated with hepatic lipid metabolism in laying hens

Dietary omega-3 polyunsaturated fatty acids (n-3 PUFA), including alpha-linolenic acid (ALA) and preformed longer chain PUFA (LCPUFA, particularly docosahexaenoic acid, DHA) differ in their egg LCPUFA enrichment efficiency. However, mechanisms leading to these differences are unclear. To this end, omega-3 PUFA contents in different lipid classes, including triacylglycerol (TAG) and total phospholipid (PL) in yolk, liver and adipose, as well as the expression of key hepatic enzymes in lipid metabolism were evaluated in laying hens in response to changes in dietary supply. Seventy Lohmann hens (n=10/treatment) consumed either a control diet (0.03% total omega-3 PUFA), or the control with supplementation (0.20%, 0.40% and 0.60% total omega-3 PUFA) from either flaxseed oil or algal product, as sources of ALA (precursor) or DHA (preformed), respectively. The study was arranged in a completely randomized design, and data were analyzed using the Proc Mixed procedure of SAS. ALA accumulated as a function of intake (P<0.0001) in total and lipid classes of yolk, liver and adipose (TAG only) for ALA- and DHA-fed hens. Unlike flaxseed oil, preformed-DHA contributed to greater (P<0.0001) accumulation of LCPUFA in yolk total PL and TAG pool, as well as adipose TAG. This may relate to elevated (P<0.0001) expression of acyl-CoA synthetase (ACSL1). No difference in hepatic EPA level in total lipids was noted between both treatment groups; EPA_liver=2.1493x-0.0064; R²=0.70, P<0.0001 (x=dietary omega-3 PUFA). The latter result may highlight the role of hepatic EPA in the regulation of LCPUFA metabolism in laying hens.

Thymol detection and quantitation by solid-phase microextraction in faeces and egg yolk of Japanese quail

To measure bioavailability of the active ingredients of phytogenic feed additives in poultry products and subproducts is a key element for developing a rational understanding of its mode of action and biological effects. Hence, we validated a headspace solid phase microextraction (HS-SPME) technique followed by gas chromatography-mass spectrometry as an analytical extraction procedure and as method for detection and quantitation of 2-Isopropyl-5-methylphenol (thymol) in faeces and egg yolk of quail. The suitability of this method for thymol analysis in both matrices was first proved via linearity, limit of detection, limit of quantification, and recovery using m-cresol as internal standard. The optimal HS-SPME extraction conditions were obtained at 40°C for 5min in faeces and 60°C for 30min in egg yolk. This procedure was found to be precise, sensitive and linear in the range of 2.5-100ng/gr for faeces and 20-800ng/gr for the egg yolk. Limits of detection were 0.5ng/g and 5ng/g for faeces and yolk, respectively, and the limits of quantitation were 1ng/g and 10ng/g for faeces and yolk, respectively. The method was successfully used for measuring thymol in fecal and egg yolk samples, from quails supplemented with thymol in their diets. Thus, in fresh faeces and egg yolk samples obtained from a supplemented group (80mg thymol per bird per day) were determined as 31.51ng/g for faeces and 11.83ng/g for the egg yolk.

Effect of flaxseed oil and microalgae DHA on the production performance, fatty acids and total lipids of egg yolk and plasma in laying hens

The incorporation of omega-3 polyunsaturated fatty acids (PUFA) in the egg is dependent on both the transfer efficiency of preformed dietary omega-3 fatty acids to the eggs as well as endogenous PUFA metabolism and deposition. Employing an experimental design consisting of 70 Lohmann LSL-Classic hens (n=10/treatment) in a 6-week feeding trial, we examined the impact of graded levels of either flaxseed oil (alpha-linolenic acid, ALA) or algal DHA (preformed docosahexaenoic acid, DHA), each supplying 0.20%, 0.40% and 0.60% total omega-3s. The control diet was practically low in omega-3s. Study parameters included monitoring the changes of fatty acid contents in yolk, measures of hen performance, eggshell quality, total lipids and fatty acid contents of plasma. Data were analysed as a complete randomized design using Proc Mixed procedure of SAS. No significant differences were observed between treatments with respect to hen performance, eggshell quality and cholesterol content in plasma and egg yolk. Individual and total omega-3 PUFA in the yolk and plasma increased (P<0.0001) linearly as a function of total omega-3 PUFA intake. At the highest inclusion levels, DHA-fed hens incorporated 3-fold more DHA in eggs compared with ALA-fed hens (179±5.55 vs. 66.7±2.25mg/yolk, respectively). In both treatment groups, maximal enrichment of total n-3 PUFA was observed by week-2, declined by week-4 and leveled thereafter. In addition, accumulation of DHA in egg yolk showed linear (P<0.0001) and quadratic (P<0.05) effects for flaxseed oil (R²=0.89) and algal DHA (R²=0.95). The current data, based on defined level of total omega-3s in the background diet, provides evidence to suggest that exogenous as well as endogenous synthesis of DHA may be subject to a similar basis of regulation, and serve to highlight potential regulatory aspects explaining the limitations in the deposition of endogenously produced omega-3 LCPUFA.

Nutritional characteristics and quality of eggs from laying hens fed on a diet supplemented with chestnut tannin extract (Castanea sativa Miller)

The trial was performed with 80 laying hens belonging to two Tuscan autochthonous breeds: 40 birds of the Mugellese (MU) breed and 40 of the White Leghorn (WL) breed. The animals were allotted to 4 groups of individually caged 20 hens each: two groups were fed on a commercial diet and worked as the control groups (MUC and WLC); the other two groups received the same diet, integrated with 2 g of chestnut tannin (CT) extract per kg of diet (MUT and WLT). A sample of 70 eggs were randomly collected and analysed for cholesterol content, fatty acid (FA) profile, weight, thickness of shell and colour of yolk. Physical parameters, including yolk colour, and indices of egg quality were not affected by the treatments. The concentration of unsaturated FAs increased, whereas cholesterol was significantly decreased: -17% in WLT and -9% in MUT. Dietary supplementation with CT extract resulted in a modification of lipid composition, towards a more healthy quality of eggs.

Increasing Levels of Dietary Hempseed Products Leads to Differential Responses in the Fatty Acid Profiles of Egg Yolk, Liver and Plasma of Laying Hens

The limited efficiency with which dietary alpha-linolenic acid (ALA) is converted by hens into docosahexaenoic acid (DHA) for egg deposition is not clearly understood. In this study, dietary ALA levels were increased via the inclusion of hempseed (HS) and hempseed oil (HO) in hen diets, with the goal of assessing the effects on the fatty acid (FA) profiles of total lipids and lipid classes in yolk, liver and plasma. Forty-eight hens were individually caged and fed one of six diets containing either HS:10, 20 or 30, HO:4.5 or 9.0 (%, diet) or a control (containing corn oil), providing a range (0.1-1.28 %, diet) of ALA. Fatty acid methyl esters of total lipids and lipid classes, including phosphatidyl choline (PtdCho) and ethanolamine (PtdEtn) in yolk, plasma and liver were then determined. Levels of n-3 FAs in both total lipids and lipid classes increased in all tissues. ALA and eicosapentaenoic acid (EPA) increased linearly, while docosapentaenoic acid and DHA increased quadratically. The FA profiles of yolk closely reflected levels in both plasma and liver. While ALA was highly concentrated in the triacylglycerol, it was low but equally distributed between PtdCho and PtdEtn in all tissues; however, the net accumulation was lower (P < 0.0001) in liver compared to yolk and plasma. Levels of EPA and ALA in yolk-PtdEtn were linearly (P < 0.0001; R (2) = 0.93) associated, and reflected those in liver-PtdEtn (P < 0.0001; R (2) = 0.90). In the liver, a strong inverse correlation (P < 0.0001; r = -0.94) between PL-DHA and ALA-to-EPA ratio in PtdEtn supports theories of low substrate availability, possibly limiting the conversion of ALA into DHA for egg enrichment.