Influence of high dose of phytase and an emulsifier on performance, apparent metabolisable energy and nitrogen retention in broilers fed on diets containing soy oil or tallow

Fat digestion and metabolism: effect of different fat sources and fat mobilisers in broilers diet on growth performance and physiological parameters – a review

Commercial broilers have a short production cycle and a high requirement for energy (3000 kcal/kg in starter phase and 3200 kcal/kg in finisher phase). Therefore, the need to add energy rich lipids to their diet is inevitable. Digestibility of fat depends on its multiple properties: chain length, the composition of fatty acids, ratio of saturated/unsaturated fatty acids and free fatty acids. The high cost of vegetable oils and less availability due to their consumption in human diet are the main reasons for searching cheaper alternative fat sources. Animal oils like poultry and fish oil are the by-product of rendering plants and after refining, they are used in poultry diets as an energy source. Due to presence of impurities and free fatty acids, the digestibility of animal fat is less. There is a limited amount of bile acids and lipase available during early age and when birds are reared on high energy diet (finisher phase). Supplementation of emusifier or lipase in broilers diet increase fat utilisation. Emulsifiers increase fat digestibility by increasing active surface area of lipid droplets. Lysolecithin and Lysophospholipids are produced from hydrolyses of lecithin and phospholipids by phopholipase A2. The bile acids mainly compose of cholic acid, hyodeoxycholic acid and chenodeoxycholic acid and have strong emulsification properties. Triacylglyceryl acylase (lipase) is an enzyme involved in catalysis and the hydrolysis of lipids. It can be concluded that use of emulsifier and lipase in broilers diet improves growth performance, nutrient digestibility and intestinal histology in broilers.

Effects of a Combination of Lysolecithin, Synthetic Emulsifier, and Monoglycerides on Growth Performance, Intestinal Morphology, and Selected Carcass Traits in Broilers Fed Low-Energy Diets

Simple Summary

Lysolecithin is produced from the enzymatic conversion of lecithin, resulting in a smaller molecule better able to improve the process of digestion of fats and oils than its progenitor. In broiler production, lysolecithin can improve performance when added to nutritionally adequate diets, but also when diets are reformulated to provide lower levels of energy and amino acids. Low-energy diets may provide more ‘space’ for growth improvements, but there is a scarcity of data on the effect of lysolecithin when added to low-energy diets containing only intact fat from raw feed ingredients. Moreover, the ability of pure lysolecithin to improve energy digestion and absorption can be further improved by the addition of synthetic emulsifiers and monoglycerides. The present study aims to evaluate the effect of supplementing a combination of lysolecithin, synthetic emulsifier, and monoglycerides on growth performance, intestinal morphology, carcass traits, and meat characteristics in broilers fed commercially relevant low-energy diets without added oil. The results revealed that this combination could effectively improve growth performance, carcass characteristics, and intestinal morphology of broiler chickens.

Abstract

This study aimed to evaluate the effect of supplementing a combination of lysolecithin, synthetic emulsifier, and monoglycerides (LEX) on growth performance, intestinal morphology, and selected carcass traits in broilers fed low-energy diets without added oil. Three hundred one-day-old Arbor Acres (AA) broilers (40.3 ± 3.3 g) were assigned to two dietary treatments with six replicates of 25 birds each and were fed a control low-energy diet without added oil supplemented with 0 and 250 g/t of LEX for 30 days. Growth performance was measured and recorded throughout the study. At slaughter, 60 birds per treatment were used to assess the effect of LEX on the carcass traits. Final average body weight and feed conversion ratio were improved (p < 0.05) in LEX treated birds compared to control. LEX supplementation was linked to higher (p < 0.05) carcass weight and yield and to lower (p < 0.05) abdominal fat and liver weight. Moisture content was higher (p < 0.05) in ground deboned broilers from LEX treatment. Villus height was increased (p < 0.05), and crypt depth reduced (p < 0.05) in the jejunum of birds treated with LEX. This study demonstrates that supplementation of LEX to a low-energy diet without added oil improved performance, carcass weight and yield, reduced abdominal fat deposition, and improved intestinal morphology in broiler chickens.

Lysolecithin, but not lecithin, improves nutrient digestibility and growth rates in young broilers

1. The potential of lecithin and lysolecithin to improve lipid digestion and growth performance was investigated in three experiments: 1. an in vitro model that mimics the intestinal conditions of the chick, 2. a digestibility trial with chicks (5-7 days of age), and 3. a performance trial until 21 days of age. 2. In experiment 1, palm oil (PO), palm oil with lecithin (PO+L), and palm oil with lysolecithin (PO+LY) were subjected to in vitro hydrolysis and applied to Caco-2 monolayers to assess lipid absorption. 3. The in vitro hydrolysis rate of triglycerides was higher in PO+LY (k = 11.76 × 103/min) than in either PO (k = 9.73 × 103/min) or PO+L (k = 8.41 × 103/min), and the absorption of monoglycerides and free fatty acids was highest (P < 0.01) for PO+LY. In experiment 2, 90 broilers were assigned to three dietary treatments: a basal diet with 4% palm oil, and the basal diet supplemented with either 250 ppm lecithin or lysolecithin. 4. ATTD of crude fat was higher in broilers supplemented with lysolecithin, but was lower in broilers supplemented with lecithin. DM digestibility and AMEn in birds supplemented with lysolecithin were significantly higher (3.03% and 0.47 MJ/kg, respectively). 5. In experiment 3, 480 broilers were randomly allocated to four dietary treatments: basal diet with soybean oil (2%), basal diet with lecithin (2%), soybean oil diet with 250 ppm lysolecithin, or lecithin oil diet with 250 ppm lysolecithin. 6. Lecithin diets significantly reduced weight at day 10 and 21 compared with soybean oil. However, the addition of lysolecithin to lecithin-containing diets significantly improved bird performance. 7. The results of these studies showed that, in contrast to lecithin, lysolecithin was able to significantly improve the digestibility and energy values of feed in young broilers.

A Mixture of Exogenous Emulsifiers Increased the Acceptance of Broilers to Low Energy Diets: Growth Performance, Blood Chemistry, and Fatty Acids Traits

To investigate the influence of emulsifiers on broilers fed low-energy diets, the birds were distributed into three sets-the control was fed the basal diet, the second group was fed diets 50 kcal/kg less than control, and the third group was fed diets 50 kcal/kg less than control and supplemented with 500 g/ton of emulsifiers. The used mixture of exogenous emulsifiers contains phosphatidyl choline, lysophosphatidyl choline, and polyethylene glycol ricinoleate. Although the feed intake was not meaningfully affected by dietary low-energy level with emulsifier inclusion (P = 0.42), the weight gain and FCR were clearly enhanced (P = 0.005 and P = 0.044, respectively). Protein and lipids utilization were decreased by reducing energy level, but they were increased by emulsifier supplementation (P = 0.022 and P = 0.011, respectively). Liver thiobarbituric acid-reactive substances (TBARs) and muscle palmitic acid concentrations were decreased by reducing the energy level and emulsifier's supplementation (P = 0.014 and P = 0.042, respectively). However, muscle total lipids and α-tocopherol, oleic acid, linoleic acid, and α-linolenic acid were not affected by dietary treatments (P > 0.05). Interestingly, the plasma total cholesterol, HDL-cholesterol, total protein, and globulin were decreased in the low-energy group without emulsifier but they were increased by emulsifier supplementation (P = 0.008, P = 0.005, P = 0.037, and P = 0.005, respectively). It could be concluded that the mixture of emulsifier supplementation to low-energy diets enhanced fat utilization and resulted in positive effects on the growth performance, nutrient utilization, lipid peroxidation, and modified plasma lipid profiles in broilers. Getting such benefits in broilers is a necessity to reduce the feed cost and consequently the price of the product, which will lead to improved welfare of mankind.

Effects of exogenous emulsifier supplementation on growth performance, energy digestibility, and meat quality in broilers

This experiment was conducted to investigate the effects of exogenous emulsifier supplementation on growth performance, energy digestibility, and meat quality in broilers. A total of 60 Ross 308 broilers were treated for two weeks. The three dietary treatments were: (CON) basal diet; (T1) basal diet + 0.1% exogenous emulsifier, and (T2) basal diet + 0.2% exogenous emulsifier. In Period 1 (0–7 days), broilers in the T2 group showed significantly higher body weight gain (BWG) (p < 0.05) and broilers in the T1 and T2 treatment groups had significantly lower feed conversion ratios (FCR) (p < 0.05). In Period 2 (8–14 days), broilers in the T2 treatment group had significantly higher feed intake (FI) (p < 0.05). Therefore, in this experiment (from days 0 to 19), BWG and FCR were affected (p < 0.05) by the T1 and T2 treatments. Additionally, the T1 and T2 treatments with added exogenous emulsifier in the broiler feed showed significantly higher energy digestibility (p < 0.05) than the CON treatment. Broilers fed the T2 diet had higher water-holding capacity (WHC) (p < 0.05) and cooking loss than the broilers fed the CON and T1 diets. Moreover, the shearing force in the meat was decreased (p < 0.05) in broilers fed the T2 diet. In conclusion, supplementation with exogenous emulsifier to broiler diets improved growth performance, energy digestibility, and meat quality. The optimal amount of exogenous emulsifier supplementation requires further investigation.

Effect of dietary fat level and source on performance and immune system response of turkeys

An experiment was conducted to determine effects of different levels and sources of fats in diets on growth performance, carcass characteristics and immune response of turkeys during four periods (0-21, 22 to 42, 43 to 63 and 64 to 70 days of age). A completely randomized design with five treatments, six replicates and eight B.U.T.6 turkey chickens per replicate was used. Treatments included: Control diet, diet containing 2.5% of soybean oil, diet containing 2.5% fat supplement, diet containing 5% soybean oil, diet containing 5% fat supplement. The results showed that using 5% of soybean oil increased average daily gain of turkeys (89.04 g) throughout the experimental period (0-70 days) compared with the control group (81.11 g; p < 0.05). Treatments containing 2.5 and 5% soybean oil improved feed conversion ratio compared to control group (p < 0.05). Soybean oil at the levels of 2.5 and 5% was led to higher spleen and bursa percentages compared to other treatments, respectively (p < 0.05). The level and source of dietary fat had not significant effect on antibody titer against Newcastle virus vaccine on 42 and 70 days of age (p > 0.05). It can be concluded that supplementing diet with 5% soybean oil improved the performance of turkeys.

The Effect of Emulsifier on Growth Performance and Fat Digestibility in Turkeys

The present study investigated the effect of an emulsifier with very high hydrophilic-to-lipophilic balance (HLB) value (18) on growth performance and fat digestibility in turkeys. A total of 1120 day-old female Hybrid Converter turkeys were randomly divided into four treatment groups with 7 replicates (pens) of 40 birds each. Control group (T1) turkeys were fed a basal diet (BD), while turkeys from experimental groups received different levels of the commercial emulsifier VE added to diets with standard or reduced metabolizable energy (ME) content: T2 – BD + 500 ppm of VE; T3 – BD + 500 ppm of VE until 8 weeks of age, and 250 ppm from 9 to 16 weeks; T4 – BD – 3% ME + 500 ppm of VE until 8 weeks of age, and 250 ppm from 9 to 16 weeks. Regardless of its dietary inclusion level (500 g/ton and 500/250 g/ton feed), the emulsifier positively influenced the body weights (BW) and body weight gains (BWG) of birds. On days 56 and 112, significant differences in the values of these parameters were noted between the control treatment (T1) vs. groups T2 and T3. Emulsifier addition even contributed to an increase in the BWG and BW of birds receiving diets with 3% lower ME content, as compared with turkeys fed control diets. This shows that the emulsifier more than compensated the reduction in ME in T4. The turkeys from group T3 were characterized by significantly higher feed efficiency than T1 and T4 birds. The highest fat digestibility was noted in turkeys fed diets with a standard ME level and emulsifier addition (T2 and T3). In conclusion, the use of dietary emulsifier positively influences the growth performance of turkeys, and improves fat digestibility.

Comparative evaluation of lysolecithin from rice bran oil vis-à-vis lipotropic agents in broiler chicken diet

The possibility of using lysolecithin from rice bran oil (LL) as a lipotropic agent was explored in the diet of broiler chickens. The LL was evaluated at 0.1 and 0.5% levels in diet vis-à-vis choline chloride, betaine or a commercial LL (0.1% of any) in broiler chickens (270) from 0 to 35 d of age. The diets were isonitrogenous and isocaloric. Body weight at 35 d was significantly higher in the group fed betaine, while LL showed no effect on growth, feed consumption, serum cholesterol concentration, slaughter variables and liver protein, and fat contents in comparison to control. The serum concentration of triglycerides at 35 d of age, however, decreased significantly with betaine, commercial LL and rice bran oil LL at both the levels. It is concluded that rice bran oil LL at dietary levels upto 0.5% showed no adverse effect on performance and reduced serum triglycerides content in broiler chickens, while betaine improved body weight.