Quality assessment of eggs from laying hens fed a mixture with lucerne protein concentrate

Poultry nutrition

Nutrition is the most important environmental factor affecting development, health status, growth performance and profitability of poultry production. Feeds for poultry constitute up to 70–75% of total production costs. Poultry nutrition differs considerably from that of other livestock, which is determined by the specific anatomy of the gastrointestinal tract. Protein, energy, fat, fiber, minerals, vitamins, and water are of basic importance for poultry nutrition and their content in feeds must cover the requirement that differ depending on the bird’s age and species. In general, feed protein must be of good value including the content of essential amino acids. Among them lysine, methionine, cysteine, threonine and tryptophan are the limiting ones. The main ingredient of poultry feeds are cereal grains, i.e. wheat and maize, which predominantly constitute an energy source because their protein content is insufficient for birds. Because of that cereals cannot be the only feed for poultry and must be combined with protein sources such as soybean or rapeseed meal, legume seeds or protein concentrates. Despite birds’ requirement for nutrients and chemical composition of feeds are well known, nutrition must face many problems. One of the most important issues is to find alternatives to antibiotic growth promoters.

Growth Performance, Biochemical Blood Indices, and Large Intestine Physiology of Rats Fed Diets with Alfalfa Protein-Xanthophyll Concentrate

The effect of dietary levels of alfalfa protein-xanthophyll concentrate (PXC) was determined in growing rats. Three groups of eight four-week-old male Wistar rats, with an average initial body weight of 61 g, were fed for 28 days either natural-ingredient diets without PXC or supplemented with 1.5% or 3% PXC. Growth performance, blood biochemistry, caecal fermentation, morphology of the large intestine, and mucin gene expression were evaluated. PXC did not affect growth performance but tended to decrease relative liver weight. Among biochemical blood parameters, only bilirubin decreased and uric acid increased in response to 1.5% and 3% PXC, respectively. Caecal fermentation was not affected, with the exception of isovaleric acid concentration, which tended to be higher in rats fed the diet containing 3% PXC. Colonic crypts tended to be deeper in rats fed the 3% PXC diet and the thickness of the colonic mucus layer was reduced by both PXC levels. In conclusion, PXC did not affect growth performance or caecal fermentation but decreased thickness of the protective mucus layer in the colon.

Effects of dietary alfalfa protein concentrate on lipid metabolism and antioxidative status of serum and composition and fatty acid profile and antioxidative status and dietetic value of muscles in broilers

The aim of this study was to determine the effect of addition of alfalfa protein concentrate (APC) at the dose of 15 g or 30 g per 1 kg on the chemical composition, fatty acid profile, dietary value, and antioxidant status in muscles and serum of Ross 308 chickens. The experiment involved 150 1-day-old Ross 308 broiler chickens allocated into 3 groups in 5 replications (10 birds per pen). A 1-way system with 2 levels of APC, 15 g or 30 g per 1 kg of a complete diet, was used. Group C receiving a standard feed mixture without APC was the control. The addition of 15 and 30 g APC increased the CP content in the breast muscle and in the thigh muscle, and reduction in the cholesterol and fat level was noted. Higher content of polyunsaturated fatty acids from the n-6 group was noted in the breast muscles of the 30-g APC-supplemented chickens. The thigh muscles with APC were characterized by more favorable values of the atherogenic index, thrombotic index, and hypocholesterol-to-hypercholesterol ratio.The supplementation with 30 g APC reduced the cholesterol and triacylglycerol levels, increased the high-density lipoprotein level, and decreased the low-density lipoprotein level and improved the antioxidant parameters in plasma (increase in superoxide dismutase and in glutathione peroxidase and reduction of malondialdehyde), compared with group C. The results of this study indicate that the supplementation with 30 g APC improved the metabolic functions of the organism, meat resistance to oxidative processes, and the composition and profile of fatty acids. Therefore, APC can be a potential alternative to synthetic feed additives and soya protein in production of healthier poultry meat.

Biorefined grass-clover protein composition and effect on organic broiler performance and meat fatty acid profile

Protein extracted from green biomass can be a sustainable and valuable feed component for organic poultry production. Earlier studies in rats have shown high digestibility of laboratory-scale extracted protein. The aim of this study was to test the effect of upscaling the biorefining process on composition of protein extracted from organic grass-clover and on performance of organic broilers when including grass-clover in the feed. Crude protein content of the extracted grass-clover protein was 36.2% of dry matter (DM) with a higher methionine content, but lower lysine and total sulphur-containing amino acids than that in soybean. Acid-insoluble residue constituted a major fraction of the dietary fibre content, and a large proportion of total CP was bound in this fraction. Alpha-linolenic acid was the dominating fatty acid in the extracted grass-clover protein. One-day-old organic Colour Yield broiler chicks were included in a dose-response trial with grass-clover protein constituting 0%, 8%, 16% or 24% of the feed from day 12 and until slaughter at day 57. Increasing levels of grass-clover protein extract reduced feed intake, growth and slaughter weight; however, at 8% inclusion feed intake and performance were not affected. The fatty acid composition in broiler breast meat reflected the composition of grass-clover protein extract; thus, the increasing dietary addition increased meat alpha-linolenic acid content. A lowered tocopherol content in meat from broilers fed increasing grass-clover protein demonstrated the need for increased amounts of antioxidants due to the high content of unsaturated fat. In conclusion, the study shows that broilers can grow on grass-clover protein from an upscaled biorefining process, but highlights the importance of further optimisation with focus on increased protein content and on avoiding formation of insoluble protein complexes, as these most likely reduce protein digestibility.

Egg Quality from Siciliana and Livorno Italian Autochthonous Chicken Breeds Reared in Organic System

In poultry production, the intensive use of high-performing hybrid animals led to loss of genetic variability and a consequent lower response to climatic change and disease. Poultry biodiversity is seriously threatened, and its safeguard is a strong objective in developed countries. According to the FAO, which emphasized the importance of native breeds for its country of origin, the aim of this study was to present the first contribution on eggs quality for endangered the Siciliana chicken breed and deepen knowledge on the local Livorno breed. At 20 weeks of age, 108 laying hens (54 Siciliana breed and 54 Livorno breed) were divided into six homogeneous groups of 18 hens each and reared according to requirements imposed by the EC Regulation 889/08 for organic production. The production cycle was controlled over one year, and egg production was recorded daily by group. Eggs were collected, weighted, and measured. Physico-chemical parameter and fatty acids profile were analyzed and nutritional indexes calculated. The statistical model included the effects of breed (Siciliana, Livorno). Egg production was 190 egg/head for Siciliana and 180 for Livorno group. The results showed similar values for Siciliana and Livorno egg quality, highlighting several valuable quality traits from these breeds which might be taken into account for conservation programs.

Quality of Eggs, Concentration of Lysozyme in Albumen, and Fatty Acids in Yolk in Relation to Blue Lupin-Rich Diet and Production Cycle

In recent years, the interest in lupin seeds as a source of protein in poultry nutrition has increased. The aim of this study was to assess the quality of table eggs produced by hens that were fed diets containing pea seeds and various levels of narrow-leafed lupin as a substitute for soybean meal. The share of lupin seeds in the treatment groups was 10%, 15%, 20% and 25%. Egg morphology, the fatty acid profile in egg yolk and the amount and activity of lysozyme in egg white were analysed. Results show that using 10-20% lupin seeds in feed in the diet of laying hens in intensive farming does not result in a change in weight or egg structure, their physical properties or their morphological composition. Increasing the share of lupin seeds in feed for laying hens increases the saturation of the colour of egg yolks, which is a desirable feature among consumers. The use of lupin seeds in feed for laying hens does not adversely affect the chemical properties of egg proteins, as expressed by the amount and activity of lysozyme. In feed for laying hens, replacing soybean meal with lupin seeds has a positive effect on the fatty acid profile in egg yolk (omega-3 and -6 polyunsaturated acids and hypocholesterolemic acids).

Effects of dietary alfalfa protein concentrate supplementation on performance, egg quality, and fatty acid composition of raw, freeze-dried, and hard-boiled eggs from Polbar laying hens

The aim of this study was to determine the effect of addition of alfalfa protein concentrate (APC) at the dose of 15 g or 30 g per 1 kg of complete feed ration for the native Polbar breed on selected production traits and the fatty acid profile in the yolk of raw, hard-boiled or freeze-dried eggs. Laying hens were assigned randomly to 3 experimental groups, each comprising 30 birds. The control group received a standard diet without the APC addition and the experimental groups received APC, which partially replaced postextraction soybean meal. Egg laying performance, feed intake, and feed conversion ratio were controlled throughout the experiment. At 33 wk of age, 45 eggs were randomly selected for assessment of the quality of the egg content and eggshell, and 30 eggs were taken for each of the cooking and freeze-drying treatments. The fatty acid composition was determined in the yolks of hard-boiled, freeze-dried, and raw eggs. There was no effect of the APC addition on the laying performance, feed intake and feed conversion ratio, and a majority of egg quality traits. Hens fed with the APC laid eggs with a darker colored eggshell and yolk and a slightly lower breaking strength. The yolks in the eggs from hens receiving the APC addition were characterized by distinctly higher content of polyunsaturated fatty acids (PUFA). The group fed with a higher dose of APC produced eggs with a substantially lower level of saturated fatty acids (SFA). Boiling resulted in an increase in the SFA content and a decline in the level of PUFAs and carotenoids. Freeze-drying led to an increase in the total SFA content and a decrease in the level of n-3 PUFA. The APC addition to feed can replace the genetically modified soybean meal without reducing the values of production traits and egg quality and with a beneficial effect on the yolk color and fatty acid profile.

Goat kid slaughter value and muscle quality after dietary supplementation with an alfalfa protein–xanthophyll concentrate

Abstract. The objective of this study was to determine the effect on goat kids of supplementation with protein–xanthophyll concentrate (PX) obtained from alfalfa (Medicago sativa). Assessments were made on carcass dressing percentage and the lipid profiles of muscle tissue. When the animals reached 30 days old (the start of the fattening period), they were allocated to two feeding groups: a control group (K), which received a standard concentrate diet, and an experimental group (D), which was fed a modified control diet where 3 % of the soybean meal was replaced with an alfalfa protein–xanthophyll preparation (PX). For the rest of the study the kids had ad libitum access to dam milk, hay and their respective diets. After 90 days of rearing (from the end of the fattening period up to when the kids were approximately 120 days of age), five (male) kids were randomly selected from each group and slaughtered. Overall, PX supplementation in goat kids does not affect any parameters of fattening, such as slaughter weight, daily weight gains or dressing percentage. However, beneficial effects of feeding with PX concentrate were found in a higher loin percentage and improved tissue composition resulting from lower fat tissue content. Moreover the PX dietary supplement improved the chemical composition of the muscle tissue by increasing the content of protein and unsaturated fatty acids. Taken together, our results suggest that supplementing the fattening diet for goat kids with the PX preparation did not affect the quantitative parameters of fattening but had a positive influence on the quality of carcass composition.

Fatty acid and cholesterol profiles and hypocholesterolemic, atherogenic, and thrombogenic indices of table eggs in the retail market

Background

Eggs are an important source of food due to its favorable effects on human health derived from the protein, fats, minerals, vitamins and bioactive components. We studied the effects of source of eggs in the retail market on fatty acids, lipid profiles and antioxidant status in eggs.

Methods

Eggs from four sources named A, B, C, and D in the retail market were collected to determine fatty acid, total lipid, and cholesterol profiles; hypocholesterolemic, atherogenic and thrombotic indices; antioxidant status (e.g., of malondialdehyde); and total antioxidant capacity in the whole edible parts of eggs (albumen + yolk) and egg yolk. Samples were collected four times and pooled over times to represent 5 and 10 samples per source for determinations of fatty acids and determinations of lipid profiles and antioxidant status, respectively.

Results

Fatty acid, total lipid, and cholesterol profiles; hypocholesterolemic, atherogenic and thrombotic indices; presence of malondialdehyde; and total antioxidant capacity in the whole edible parts of eggs and egg yolk showed significant differences (P ≥ 0.05) among different sources of eggs in retail market. Source D showed higher levels of saturated fatty acids (SFA) and linoleic and monounsaturated fatty acid (MUFA)/polyunsaturated fatty acid (PUFA) ratio but lower levels of MUFA and linolenic, arachidonic, eicosapentaeonic (EPA), decohexaenoic (DHA), and total ω9 fatty acids and lower unsaturated fatty acids (UFA)/SFA ratio. Similar trend was shown in fatty acids profiles of the whole edible parts of eggs. On the other hand, total cholesterol, low density lipoprotein (LDL), LDL/high density lipoprotein (HDL) ratio, and atherogenic and thrombogenic indices and total antioxidant capacity of source D were significantly higher than those of other source, but levels of hypocholesterolemic index, and malondialdehyde levels were lower for source D.

Conclusion

Eggs in the retail market in Jeddah city, Saudi Arabia, from May to August 2015 showed a different pattern of fatty acid and cholesterol profiles; hypocholesterolemic, atherogenic, and thrombogenic indices; and antioxidant status, which might reflect the nutritional and husbandry practice of laying hens. This can affect the nutritional values of eggs, and hence, customer benefits, suggesting the need for standardization and quality control based on nutrient index values.

Effect of humic-plant feed preparations on biochemical blood parameters of laying hens in deep litter housing system

An influence of various humic-plant feed additives based on some herbs (nettle, chamomile, yarrow, perforatum), lucerne and humic materials on biochemical indices of Lohmann Brown (LB) layers blood plasma was estimated. Hens were housed in deep litter system, 20 birds in a group. Four groups were formed: control (C – standard feeding), and experimental, supplemented with preparations: E-1 herbal-humic, E-2 humic-herbal and E-3 – humic-lucerne. Hens were placed in the pens on the 16thweek of life, addition of preparations with standard food mixture started at the 22ndwk and lasted until 66thwk of life. Blood for analyses was collected four times in the following periods: 27, 37, 54 and 65thwk of life. The applied humic-plant preparations to a limited degree affected the values of examined biochemical parameters in serum: total protein (TP), albumins (Albs), glucose (Glu), urea, triacylglycerols (TAG), total cholesterol (TCh), alanine aminotransferase (ALT), aspartate aminotransferase (AST) and alkaline phosphatase (ALP). It is difficult to determine based on these study, which preparation is one the most active biologically, however is seems that humic-lucerne preparation affected the examined blood parameters to the highest degree. The reference values ranges in hens blood serum LB hens were proposed for: TP (43-65 g/l), Albs (15-22 g/l), urea (0.5-1.2 mmol/l), Glu 10-15 mmol/l), TCh (2.2-4.5 mmol/l), TAG (10-24 mmol/l), AST (4-12 U/l), ALT (150-280 mmol/l) and ALP (190-350 U/l).