Growth Performance of Broilers as Influenced by Different Levels and Sources of Methionine Plus Cysteine

Effects of methionine supplementation in a reduced protein diet on growth performance, oxidative status, intestinal health, oocyst shedding, and methionine and folate metabolism in broilers under Eimeria challenge

BACKGROUND

This study investigated effects of different methionine (Met) supplementation levels in a reduced protein diet on growth performance, intestinal health, and different physiological parameters in broilers under Eimeria challenge. A total of 600 fourteen-day-old Cobb500 male broilers were challenged with E. maxima, E. tenella, and E. acervulina, and randomly allocated in a 2 × 5 factorial arrangement. Birds received normal protein diets (20% crude protein, NCP) or reduced protein diets (17% crude protein, LCP), containing 2.8, 4.4, 6.0, 7.6, and 9.2 g/kg of Met.

RESULTS

On 6 and 9 days post inoculation (DPI), increasing Met level linearly improved the growth performance (P < 0.05). Total oocyst shedding linearly increased as Met level increased (P < 0.05). Duodenal villus height (VH):crypt depth (CD) in the LCP groups were higher on 6 DPI (P < 0.01) while lower on 9 DPI (P < 0.05) compared to the NCP groups. Jejunal CD and duodenal VH:CD changed quadratically as Met level increased (P < 0.05). On 6 DPI, liver glutathione (GSH) and glutathione disulfide (GSSG) linearly increased as Met level increased (P < 0.05). On 9 DPI, GSSG quadratically increased, whereas GSH:GSSG quadratically decreased as Met levels increased (P < 0.05). The expression of amino acid transporters linearly decreased as Met level increased (P < 0.05). The expression of zonula occludens 2 and claudin-1 linearly increased on 6 DPI whereas decreased on 9 DPI as Met level increased (P < 0.05). The expressions of cytokines were lower in the LCP groups than the NCP groups (P < 0.05). Interaction effects were found for the expression of IL-10 and TNFα on 6 DPI (P < 0.05), where it only changed quadratically in the NCP group as Met level increased. The expression of Met and folate metabolism genes were lower in the LCP groups than the NCP groups on 9 DPI (P < 0.05). The expression of these genes linearly or quadratically decreased as Met level increased (P < 0.05).

CONCLUSION

These results revealed the regulatory roles of Met in different physiological parameters including oxidative status, intestinal health, and nutrient metabolism in birds fed reduced protein diet and challenged with Eimeria.

Relative biological efficacy of methionine hydroxy analogue-free acid compared to dl-methionine in the broiler chickens

BACKGROUND

In the broiler's diets based on corn-soya bean meal, methionine (Met) and cystine (Cys), known as sulphur amino acids (SAAs), are the first limiting indispensable amino acids because of their limited presence, which are supplemented with different synthetic sources. Evaluation of the biological effectiveness of these sources can be important in their correct replacement, especially in the starter and growth diets.

OBJECTIVES

The current study was done to assess the relative biological efficacy (RBE) of liquid Met hydroxy analogue-free acid (MHA-FA) in comparison with dl-Met (dl-Met) based on broiler performance traits at different levels of digestible SAA in the 1-11 (starter) and 11-25 (grower) days of age periods.

METHODS

Two experiments were developed with treatments consisting of a basal diet without Met addition that met the nutrient and energy requirements of broilers with the exception of SAAs (Met + Cys) and five increasing Met doses for both sources (dl-Met and/or MHA-FA), resulting in digestible SAA concentrations from 0.62% to 1.02% of diet in the starter period (Trial 1) and 0.59% to 0.94% of diet in the grower period (Trial 2). The multi-linear regression model and slope ratio method were employed to calculate the RBE of MHA-FA compared with dl-Met for measured variables.

RESULTS

In both experiments, the results obtained during the starter and grower periods with the different Met supplementations show significant growth responses to digestible SAAs levels. By increasing dietary dl-Met and/or MHA-FA levels, the growth performance traits and immune responses were improved (quadratic; p < 0.05). The RBE of MHA-FA compared to dl-Met on an equimolar basis was estimated 66%-89% (59%-79% on a weight-to-weight basis).

CONCLUSIONS

It is concluded that the RBE of MHA-FA in comparison with dl-Met depends on broiler chicken age and what attribute is being evaluated.

Dietary L-Methionine modulates the gut microbiota and improves the expression of tight junctions in an in vitro model of the chicken gastrointestinal tract

BACKGROUND

The poultry industry encounters a number of factors that affect growth performance and productivity; nutrition is essential for sustaining physiological status and protecting against stressors such as heat, density, and disease. The addition of vitamins, minerals, and amino acids to the diet can help restore productivity and support the body's defense mechanisms against stress. Methionine (Met) is indispensable for poultry's energy metabolism, physiology, performance, and feed utilization capacity. Through this study, we aimed to examine the physiological effects of methionine supplementation on poultry as well as alterations of intestinal microbiome.

METHODS

We utilized the DL- and L- form of methionine on Caenorhabditis elegans and the FIMM (Fermentor for intestine microbiota model) in-vitro digesting system. A genomic-analysis of the transcriptome confirmed that methionine supplementation can modulate growth-related physiological metabolic pathways and immune responses in the host poultry. The C. elegans model was used to assess the general health benefits of a methionine supplement for the host.

RESULTS

Regardless of the type or concentration of methionine, supplementation with methionine significantly increased the lifespan of C. elegans. Feed grade L-Methionine 95%, exhibited the highest lifespan performance in C. elegans. Methionine supplementation increased the expression of tight junction genes in the primary intestinal cells of both broiler and laying hens, which is directly related to immunity. Feed grade L-Methionine 95% performed similarly or even better than DL-Methionine or L-Methionine treatments with upper doses in terms of enhancing intestinal integrity. In vitro microbial cultures of healthy broilers and laying hens fed methionine revealed changes in intestinal microflora, including increased Clostridium, Bacteroides, and Oscillospira compositions. When laying hens were given feed grade L-Methionine 95% and 100%, pathogenic Campylobacter at the genus level was decreased, while commensal bacteria were increased.

CONCLUSIONS

Supplementation of feed grade L-Methionine, particularly L-Methionine 95%, was more beneficial to the host poultry than supplementing other source of methionine for maintaining intestinal integrity and healthy microbiome.

Methionine sources and genotype affect embryonic intestinal development, antioxidants, tight junctions, and growth-related gene expression in chickens

Methionine (Met) is an essential and first limiting amino acid in the poultry diet that plays a significant role in chicken embryonic development and growth. The present study examined the effect of in ovo injection of DL-Met and L-Met sources and genotypes on chicken embryonic-intestinal development and health. Fertilized eggs of the two genotypes, TETRA-SL layer hybrid (TSL) - commercial layer hybrid and Hungarian Partridge colored hen breed (HPC) - a native genotype, were randomly distributed into four treatments for each genotype. The treatment groups include the following: 1) control non-injected eggs (NoIn); 2) saline-injected (SaIn); 3) DL-Met injected (DLM); and 4) L-Met injected (LM). The in ovo injection was carried out on 17.5 d of embryonic development; after hatching, eight chicks per group were sacrificed, and the jejunum was extracted for analysis. The results showed that both DLM and LM groups had enhanced intestinal development as evidenced by increased villus width, villus height, and villus area (P < 0.05) compared to the control. The DLM group had significantly reduced crypt depth, glutathione content (GSH), glutathione S-transferase 3 alpha (GST3), occludin (OCLN) gene expression and increased villus height to crypt depth ratio in the TSL genotype than the LM group (P < 0.05). The HPC genotype has overexpressed insulin-like growth factor 1 (IGF1) gene, tricellulin (MD2), occludin (OCLN), superoxide dismutase 1 (SOD1), and GST3 genes than the TSL genotype (P < 0.05). In conclusion, these findings showed that in ovo injection of Met enhanced intestinal development, and function, with genotypes responding differently under normal conditions. Genotypes also influenced the expression of intestinal antioxidants, tight junction, and growth-related genes.

The beneficial effect of nanomethionine supplementation on growth performance, gene expression profile, and histopathology of heat-stressed broiler chicken

This study investigated the effects of nanomethionine (nano-meth) on performance, antioxidants, and gene expression of HSP70, HSP90 and Heat Shock factor-1 (HSF-1) from the liver, and TLR4 from the jejunum, of broiler chickens reared under normal temperatures or under heat stress. Three hundred 1-day-old chicks were randomly assigned to 5 treatment groups. Group 1 served as control. Under normal temperature, birds in group 2 received nano-meth (10 mL/L of drinking water) from d1 until the experiment ended. Group 3 birds were heat-stressed (HS) and did not receive any supplementation. Group 4 received nano-meth in the same dose from d1 old until experiment ended, and the birds were exposed to HS. Group 5 birds were HS and received supplementation of nano-meth during the HS period only. Nano-meth improved (P < 0.0001) final body weight, weight gain, feed conversion ratio, and also decreased (P < 0.0001) the effect of HS on growth performance. Reduction (P < 0.0001) in malondialdehyde and changes in antioxidant enzymes GPX and CAT activity indicated the antioxidant effect of nano-meth. Nano-meth supplementation caused an increase in the expression of HSP70 , HSP90 and HSF1, and a downregulation of TLR4 gene expression. Additionally, nano-meth-supplemented groups showed marked improvement in the histological liver structure, intestinal morphology and villus height compared to control or HS groups.

Assessing the nutritional equivalency of DL-methionine and L-methionine in broiler chickens: a meta-analytical study

The purpose of this study was to perform a meta-analysis comparing the biological efficiency of DL-methionine and L-methionine (DL-Met and L-Met) in broiler nutrition. This analysis was based on a dataset comprising experiment results published in peer-reviewed papers since 2007. All experiments investigated the response of broilers (aged 0-21 d) to different dietary concentrations of DL- and L-Met, achieved by supplementing crystalline Met. A graphical analysis was conducted on the database using ellipses coverage and nonparametric density techniques. Two methods of linear and nonlinear exponential meta-regression analysis were used to determine relative bioavailability based on average daily gain (ADG) and feed conversion ratio (FCR) responses to dietary Met sources. The analyses of ADG and FCR obtained from both linear and exponential models showed a relative difference between the tested methionine sources. The results showed that both ADG and FCR were improved in L-Met compared to DL-Met supplemented diets. Linear regression analysis revealed that DL-Met was 94.97% (for ADG) and 95.63% (for FCR) as efficacious as L-Met (P < 0.01). In contrast, the analysis of the fitted nonlinear exponential model showed that the biological efficiencies of DL-Met were 91.33% and 76.57% of the values for L-Met for ADG (P = 0.01) and FCR (P = 0.09), respectively. Based on the meta-analytical results, an equivalence of relative biological efficiency of DL-Met in comparison with L-Met for young broilers could not be confirmed.

Meta-analysis of blood indices and production physiology of broiler chickens on dietary fermented cassava intervention

The effects of dietary fermented cassava on the blood constituents and production parameters of broiler chickens have been reported with variable outcomes. Therefore, this investigation aimed to explore the impacts of dietary fermented cassava on growth traits, blood constituents, visceral organ, and carcass characteristics of broiler chickens. Four databases were searched for studies that assessed responses of broiler chickens dietary fermented cassava. Eleven articles were used for the investigation, and data generated were analysed using OpenMEE software. A random effects model was used, and effect sizes were presented as standardised mean difference (SMD) at a 95 % confidence interval (CI). Sources of heterogeneity were evaluated using the following modifiers: broiler strain used, cassava form, feeding duration, type of microbes used for the fermentation, and inclusion level of cassava. Results indicate that fermented cassava-based diets increased feed intake (SMD = 0.38; 95 % CI: 0.11, 0.65; P = 0.006), feed conversion ratio (SMD = 1.26; 95 % CI: 0.91, 1.61; P < 0.001), white blood cells (SMD = 1.26; 95 % CI: 0.54, 1.98; P < 0.001), total serum protein (SMD = 1.23; 95 % CI: 0.41, 2.05; P = 0.003), serum cholesterol (SMD = 0.43; 95 % CI: 0.01, 0.85; P = 0.050), serum creatinine (SMD = 2.53; 95 % CI: 0.53, 4.53; P = 0.013), and serum uric acid (SMD = 4.33; 95 % CI: 6.25, 2.41; P < 0.001), but lowered average daily gain and carcass yield, taking heterogeneity into account. Results reveal that studied modifiers were responsible for the inconsistent results among authors. In conclusion, dietary fermented cassava negatively influenced carcass yield, growth performance, and aspects of blood indices of broiler chickens, but did not affect abdominal fat content, visceral organ weights, and cut-part weights. However, more innovative research is needed to improve the feeding quality of cassava using other biotechnological tools in order to maximise its potential as an energy source in broiler chickens.

Behavioural Patterns and Growth Performance of Male Wistar Rats Exposed to Cigarette Smoke: Effects of Curcumin and Hesperidin

This study evaluated the behavioural responses of male Wistar rats to normal air or cigarette smoke (CS) and compared the effects of curcumin and hesperidin on growth performance. In experiment 1, male rats were randomised into two groups (n = 10): control and CS-exposed groups. During exposure (four weeks), the dietary and behavioural patterns were monitored. In experiment 2, forty-eight rats were distributed across eight groups (n = 6): normal control, CS control, CS + curcumin (10 mg.kg−1), CS + curcumin (20 mg.kg−1), CS + hesperidin (10 mg.kg−1), CS + hesperidin (20 mg.kg−1), curcumin (20 mg.kg−1), and hesperidin (20 mg.kg−1) for 6 weeks. Growth performance (feed intake, weight gain, and feed conversion ratio FCR) were assessed. In the first experiment, there was no significant difference (P > 0.05) in the body weight of the CS-exposed group compared to the normal control, whereas feed intake was significantly (P > 0.05) lower in the CS-group. The time to access feed and water was higher in the CS-group, while other behavioural responses (locomotion, stand upright, climbing, stand and stare, sniffing, sitting, and digging) were significantly reduced (P < 0.05) compared with normal control, especially after two weeks. In the second experiment, weight gain, feed in-take, and FCR were significantly lower in the CS-exposed group compared to the control group, whereas treatment with curcumin and hesperidin, especially at the higher dose (20 mg.kg−1 b. wt.), significantly improved the growth performance of the CS-exposed groups. This study submits that CS exposure negatively impacts on the growth performance and behavioural patterns and demonstrates the potentials of curcumin and hesperidin in addressing these CS-provoked changes.

Influences of total sulfur amino acids and photoperiod on growth, carcass traits, blood parameters, meat quality and cecal microbial load of broilers

The current study aimed to discuss the impact of total sulfur amino acids (TSAA) %, photoperiod, and their interaction on growth performance, carcass and blood indices of broiler chicks. A total of 300 unsexed IR broiler chicks one-week old were used in a factorial arrangement (2 × 3), including two photoperiod systems (22 L: 2 D and 16 L: 8 D) and three experimental rations having three grades of Met + Cyst (TSAA) (70%, 85% and 100% of digestible lysine in starter and finisher diets). Results revealed that the higher LBW and BWG were noticed in birds given TSAA at grades of 1.1 or 0.90 % under 22L: 2D photoperiod at five weeks of age and the whole experimental period (1–5 weeks of age), respectively. The highest live body weight (LBW (and body weight gain (BWG) were recorded in birds received 1.1% TSAA under the long photoperiod compared to the control and the other groups. Birds fed 1.3% TSAA consumed more feed than the other groups. The opposite was found in birds fed 1.1% TSAA under the short photoperiod (16L: 8D). The best feed conversion (FCR) was detected by birds fed 1.1% and 0.90% TSAA diets during the whole experimental period. All carcass traits studied were significantly influenced by TSAA levels, except for the relative weights of abdominal fat and spleen. The interaction effect on was significant on all carcass traits except spleen %. In conclusion, the addition of TSAA at level 1.1 and 0.9 % to starter and finisher diets under a long photoperiod regime improved broiler’s performance, carcass traits, and blood parameters studied.

Influence of dietary L-carnitine and lysine-methionine levels on reproductive performance and blood metabolic constituents of breeder ducks

The present study aimed to evaluate the influence of dietary supplementation of different levels of L‐carnitine and/or lysine–methionine (Lys‐Met) on reproductive performance of breeder ducks. Three L‐carnitine (0, 75 and 150 mg/kg) and three lysine–methionine (100%, 110% and 120% above the NRC (Nutrient requirements of poultry, 1994, National Academy Press) recommendations) levels were fed to 180 breeder ducks (144 females and 36 males) in a completely randomized design for 49 days. Laying performance and reproductive traits were evaluated; additionally, uric acid, total protein total, triglycerides, total cholesterol, low‐density lipoprotein, high‐density lipoprotein, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were assessed. The Lys‐Met above 100% NRC (Nutrient requirements of poultry, 1994, National Academy Press) recommendations with or without L‐carnitine improved feed utilization (p < .05). Furthermore, Lys‐Met above 100% recommendations without L‐carnitine improved egg fertility and hatchability. Fertility and hatchability improved in breeders fed on L‐carnitine with 120% Lys‐Met (p < .05). Serum glucose increased and total cholesterol reduced on 100% Ly‐Met without L‐carnitine or 110% Ly‐Met with 150 mg L‐carnitine (p < .05). Glucose was reduced, while total cholesterol increased on 75 mg L‐carnitine and 100% Lys‐Met (p < .05). Increasing Lys‐Met without L‐carnitine reduced serum protein (p < .05). Albumin and ALT increased on 75 mg L‐carnitine–100% Lys‐Met and reduced on 150 mg L‐carnitine–120% Lys‐Met (p < .05). There were no interaction effects on globulin, uric acid and AST (p > .05). Thus, based on findings, breeder ducks responded to dietary Lys‐Met more efficiently than L‐carnitine; however, more research is needed to evaluate also economic aspects related to L‐carnitine dietary supplementation.

The impact of betaine supplementation in quail diet on growth performance, blood chemistry, and carcass traits

The study aimed to investigate the effect of various doses of betaine supplemented dietary on Japanese quail performance, carcass characteristics, and blood chemistry. Therefore, 400 seven days old Japanese quails were classified randomly into four equal groups. Each group was subdivided into five replicates of 20 birds each. Four rations were formulated using four different betaine levels (0, 0.75, 1.5 and 2.25 g/kg, respectively) for five successive weeks. All groups received feed and clean water ad-libitum. The results of this trial indicated that the feed intake was lowered in groups fed with betaine (p ≤ 0.05) when compared with the control one. The highest weight gain (p ≤ 0.05) was noticed in groups fed diets BS4 (betaine supplementation at the rate of 2.25 g/kg). No difference among groups was observed in body length, shank length, shank diameter, and keel bone length or breast width. Also, the carcass weight and breast yield were highest (p ≤ 0.05) in the group reared on the BS4 diet. In addition, intestinal length and weight were significantly higher (p ≤ 0.05) in groups fed betaine with a concentration of 2.25 g/kg. Fat weight was lower in the group fed BS4 than in the untreated group. Significantly higher values of high-density lipoprotein (p ≤ 0.05) were observed in the group fed BS4. All groups fed a ration containing betaine showed lower levels of liver enzymes such as alanine amino transferase, alkaline phosphatase, and aspartate amino transferase (p ≤ 0.05) and lowered low-density lipoprotein level. The quails fed BS4 had the greatest growth hormones and insulin (p ≤ 0.05) and the lowest thyroxin level. We concluded that dietary betaine supplementation positively impacts Japanese quail growth performance, carcass traits, and blood chemistry.

Effects of Feeding Varying Levels of DL-Methionine on Live Performance and Yield of Broiler Chickens

Simple Summary

The use of DL-methionine (MET) in poultry diet formulation is vital for poultry growth because poultry do not synthesize sufficient amounts of MET needed for proper growth and performance, and currently there are insufficient natural sources of MET to fulfill the dietary needs of broiler chickens. However, the use of MET is restricted in the United States in organic poultry diets. Therefore, the objective of this study was to examine the effect of feeding different levels of dietary MET on organic broiler live performance and yield of a modern commercial broiler strain. This study gives us insight into how broiler growth and yield is affected when the allowable levels of methionine for organic broilers is further reduced, or zero methionine is used.

Abstract

This study was designed to evaluate the effects of dietary supplemental DL-methionine (MET) on live performance and meat yield for broilers raised to a common weight. A total of 1552 one-day old Ross 708, sexed broilers were randomly distributed to 32 pens resulting in eight treatments (TRT) of four replicates with 44 male or 53 female/pen. A randomized complete block with a 2 × 4 (sex × 4 MET levels 0, 0.5, 1, and 2 g/kg) factorial arrangement of TRT was used. A common weight of 2400 g was approached by day 46 (1 and 2 g MET/kg feed) and day 48 (0 and 0.5 g MET/kg feed). Supplementation of MET at 1, and 2 g/kg had a lower (p < 0.01) feed conversion ratio (FCR) at day 46/48 than broilers fed 0.5 g MET/kg. Broilers without supplemental MET had the worst (p < 0.01) feed conversion and average daily gain (ADG) at day 46/48. Birds fed 0 g MET/kg of feed had lower (p < 0.05) whole eviscerated carcass without giblets (WOG), yield than birds fed 2 g MET/kg of feed. Additionally, birds fed 0 g MET/kg of feed had lower (p < 0.05) breast fillet and tender percent yields than birds fed supplemental MET. Elimination of MET from organic broiler diets resulted in reduced ADG, breast fillet yield and feed efficiency of meat yield of broilers raised to day 46/48. Reduction in MET supplementation below current levels reduced the efficiency of meat production of organic broilers raised to day 46/48.

Biological effects of iodine, selenium, sulfur citrates in broiler chickens

This study aimed at the assessment of the I, Se, S citrate effect on the organism of broiler chickens. Feeding of chickens of all groups was carried out by using standard balanced feeds – starter, grower, and finish with the use of group feeders placed at the appropriate height from the floor depending on the poultry height. For the chickens of experimental groups, I, Se, S citrate was added to drinking water daily during the 48th day. To the drinking water of chickens of experimental groups different amounts of the citrate solution were added I (200 mg/L), Se (50 mg/L), S (300 mg/L), prepared by the nanotechnology method. Chickens of the II group received the lowest dose of I, Se, S at the rate of 5 μg I/L, 1.25 μg Se/L, 7.5 μg S/L of drinking water, and for poultry of other experimental groups, it was increased by 2 (III), 4 (IV), 6 (V) and 8 (VI) times compared to II group. Coccidiostat "Kokcisan 12%" (KRKA, Slovenia) was added to the starter and grower feed at the stages of its manufacture in quantities of 0.5 kg/t of feed. Coccidiostat was not added to the final feed. During the 48-day technological period, the clinical condition of the poultry was monitored daily by forage and motor activity, safety, and every 7 days – for growth intensity with the individual determination of body weight on a laboratory scale. The investigation of the blood was carried out from the 35th or 48th day during the growing, period and also investigation of the internal organs – liver, heart, spleen, stomach, thymus, and bursa of Fabricius. The increase of cholesterol, triacylglycerols, and albumin in the blood of II, III, and VI chicken groups was established on the 35th day of the experiment, and the reduction of creatinine in III and VI groups. By that time, the effect of highest dose of I, Se, S caused a decrease in the T3 concentration in the blood of chickens in the VI group compared to the I and II groups. In particular, in the blood of chickens of IV, V and VI groups compared to the I, II, III group under these conditions there was a significant increase in the content of urea, Ca, P, cholesterol, as well as albumin – only in IV group on the 48th day. Triacylglycerols’ content increased in the blood serum of chickens in III and IV groups compared to the II and V groups, but in V group – decreased compared to the III, IV groups. The increase in liver, thymus, and heart mass in the II and V chicken groups was noticed and their decrease in the VI group was revealed compared with the control group. Reliable lower coefficients of the body mass of chickens of III and VI groups may indicate a less notable stimulating biological effect of I, Se, S citrate in these doses on liver development than on the whole organism. The addition of I, Se, S citrate to broiler chickens during the period of growing revealed the difference in their biological action in the presence and absence of the Kokcisan 12% in a mixed fodder. A more notable stimulating effect of low dose of I, Se, S citrate on the growth and development on the chickens' organism was established during the withdrawal of coccidiostatics from their diet. The effect may be due to its inhibitory influence on the biological activity of these elements in the first 35 days of growing. In the final period of chicken growing and withdrawal of ionophore Kokcisan from the diet more noticeable changes were revealed in the studied parameters.

Methionine alleviates aflatoxinb1-induced broiler chicks embryotoxicity through inhibition of caspase-dependent apoptosis and enhancement of cellular antioxidant status

Practical methods for preventing embryotoxicity in chickens that are caused by aflatoxin-B1 (AFB1) are currently rare. Binding absorbers are commonly used in feeding stuff to reduce laying hens' exposure to off-contaminated diets, thus reducing residue exposure to fertilized eggs. Nonetheless, several adsorbents have been shown to affect the use of nutrients and the absorption of minerals in poultry. Thus, seeking an effective strategy to counter or control embryotoxicity in broiler chicks caused by AFB1 is a problem. A total of 180 embryonated eggs were injected with 36 ng AFB1 with or without 5.90 mg L-methionine (Met) 30 embryonated eggs each, followed by incubation in an incubator until hatching time. The in ovo injection of Met significantly reduced toxicity caused by AFB1 in broiler embryos by enhancing the liver and kidney functions, lipid profiles, and alleviated oxidative stress during the incubation period. Furthermore, the relative gene expressions (SSTR5, TSH-β, Bcl-2, GSH-Px, GST-a, and SOD in the liver) were up-regulated with in ovo injection of AFB1+Met compared to AFB1 alone. Moreover, there was a dowin-regulated trend in Bax, Caspases-3, Caspases-7, Caspases-9, CYP1A1, CYP2H1, and P53 gene expression with in ovo injection of AFB1+Met compared to AFB1 alone. The in ovo injection of Met led to less apoptotic cells in liver tissues. Such results might be necessary for the poultry industry as it is focused on managing the embryotoxicity of AFB1, which affecting poultry production and welfare. Results from this study demonstrated that in ovo Met injection could alleviate AF-induced toxicity in chicken embryos.

Paternal Dietary Methionine Supplementation Improves Carcass Traits and Meat Quality of Chicken Progeny

The effects that maternal dietary methionine have on progeny have been reported on broilers. However, the paternal effects are not known, so the current study was conducted to explore the influences of paternal dietary methionine (Met) have on progeny carcass traits, meat quality, and related gene expressions. A total of 192 hens and 24 roosters from Ross parent stock at 36 weeks of age were selected. From week 37 to 46, the roosters were allocated to two groups with three replicates of 4 cocks each, (control, 0.28% Met), and methionine group (MET group, 0.28% Met + 0.1% coated Met). The results revealed that, although the heavier live body weight in progeny at day 49 of control group compared to MET group (p < 0.05), the relative eviscerated yield and relative thigh muscle yield were higher in MET group (p < 0.05); but the relative abdominal fat was lower (p < 0.05). In thigh and breast muscles, a positive response of pH_{24 h} value, shear force (g) and drip loss (%) were observed in MET group (p < 0.05). The lightness (L) and redness (a) were increased (p < 0.05) in breast muscles of MET group, while only the redness (a*_{24 h}) and yellowness (b*_{24 h}) were increased (p < 0.05) in thigh muscles of MET group. The gender has a significant (p < 0.05) effect on carcass traits and muscle redness (a*), where these traits improved in males, and no interaction between treatments and gender were observed for these results. The expression levels of PRKAG2 and PRDX4 supported the changes in muscle pH, with these up-regulated in thigh and breast muscles of MET group, the PPP1R3A gene supported the changes in pH value being down-regulated (p < 0.01) in these same muscles. The BCO1 gene expression was consistent with the changes in meat color and was up-regulated (p < 0.01) in thigh muscles of MET group, consistent with the changes in b* color values. Finally, it was concluded that the supplementation of 0.1% Met to rooster diets could improve carcass characteristics and meat quality of progeny.

Nutritional significance of amino acids, vitamins and minerals as nutraceuticals in poultry production and health - a comprehensive review

Nutraceuticals have gained immense importance in poultry science recently considering the nutritional and beneficial health effects of their constituents. Besides providing nutritional requirements to birds, nutraceuticals have beneficial pharmacological effects, for example, they help in establishing normal physiological health status, prevent diseases and thereby improve production performance. Nutraceuticals include amino acids, vitamins, minerals, enzymes, etc. which are important for preventing oxidative stress, regulating the immune response and maintaining normal physiological, biochemical and homeostatic mechanisms. Nutraceuticals help in supplying nutrients in balanced amounts for supporting the optimal growth performance in modern poultry flocks, and as a dietary supplement can reduce the use of antibiotics. The application of antibiotic growth enhancers in poultry leads to the propagation of antibiotic-resistant microbes and drug residues; therefore, they have been restricted in many countries. Thus, there is a demand for natural feed additives that lead to the same growth enhancement without affecting the health. Nutraceuticals substances have an essential role in the development of the animals' normal physiological functions and in protecting them against infectious diseases. In this review, the uses of amino acids, vitamins and minerals as well as their mode of action in growth promotion and elevation of immune system are discussed.

Effects of Varying Dietary DL-Methionine Levels on Productive and Reproductive Performance, Egg Quality, and Blood Biochemical Parameters of Quail Breeders

Simple Summary

This study investigated the effects of different DL-methionine levels on quail breeders kept from 8–16 weeks of age. The results revealed that using DL-methionine at levels of 0.5 or 1.5 g/kg improved the liver and kidney functions, lipid profile, immunity and antioxidant parameters of quail breeders.

Abstract

The present study was carried out to study the effects of varying dietary DL-methionine (0, 0.5, 1.5, 2.5, and 3.5 g/kg) levels on the productive and reproductive performance, egg quality and blood biochemical parameters of quail breeders. In total, 150 mature Japanese quails at eight weeks of age were randomly allotted to five groups of 30 for each group. Each group included five replicates, each of six quails (four females and two males). The results showed that egg number, egg weight and egg mass were higher (p < 0.05) with the addition of all DL-methionine levels than that of the control group. Quails from the control group had a lower feed intake (p < 0.001) and a worse feed conversion ratio (FCR) than those from the DL-methionine-treated groups. Supplementation of DL-methionine up to 2.5 g/kg in quail diets increased fertility and hatchability percentages. Birds fed DL-methionine at 1.5 g/kg had the best egg production indices, better FCR and the highest values of fertility and hatchability. Egg weight, yolk %, Haugh unit, egg shape index and unit surface shell weight (USSW) were increased and eggshell % was decreased in quail supplemented with DL-methionine levels compared with the control quail (p < 0.05). Dietary DL-methionine levels did not affect (p > 0.05) the hemoglobin (Hb), red blood cells (RBCs), white blood cells (WBCs) and packed cell volume (PCV) of quails. DL-methionine levels (0.5 and 2.5 g/kg) augmented lymphocytes and basophile (p < 0.05). Low DL-methionine levels (0.5 or 1.5 g/kg) improved liver enzymes and kidney functions. Dietary DL-methionine levels (except 3.5 g/kg) declined serum lactate dehydrogenase (LDH) and decreased lipid profile parameters (except high-density lipoprotein—HDL). Supplementation of DL-methionine at 0.5 and 1.5 g/kg increased immunoglobulin (IgG, IgM and IgA) and superoxide dismutase (SOD), total antioxidant capacity (TAC), catalase (CAT) and reduced glutathione (GSH) (p < 0.001) compared with the control. In conclusion, dietary supplementation of DL-methionine (1.5 g/kg) can enhance the reproductive performance and egg quality of quail breeders. DL-methionine use at levels of 0.5 or 1.5 g/kg improved the liver and kidney functions, lipid profile, immunity and antioxidant parameters of Japanese quail.

Efficacy of some feed additives to attenuate the hepato-renal damage induced by aflatoxin B1 in rabbits

The present trial was conducted to evaluate the beneficial role of some feed additives (potassium sorbate; Sor, hydrated sodium calcium almuniosilicate; Hsc and l-methionine; L-M) in attenuating the hepatic and renal toxicity of aflatoxin B1 (AFB1) in rabbits. A total number of 72 NZW growing rabbits (5 week-old) were divided into six experimental groups (four replicates with three rabbits each) as follows: control group, AFB1 group (supplemented with AFB1 0.3 mg/kg diet), AFB1 + Sor group (AFB1 0.3 mg/kg diet + Sor 2 g/kg diet), AFB1 + Hsc group (AFB1 0.3 mg/kg diet + Hsc 5 g/kg diet), AFB1 + L-M group (AFB1 0.3 mg/kg diet + L-M 8 g/kg diet) and AFB1 + Mix group (AFB1 0.3 mg/kg diet + 2 Sor + 5 Hsc + 8 L-M g/kg diet). Serum levels of total protein, albumin and globulin were significantly reduced by AF. AF increased the serum activity of aspartate aminotransferase (AST), alanine amino transferase (ALT) and alkaline phosphatase (ALP) enzymes. While, they were reduced in AF + Sor and AF + Mix groups compared with AF group. AF increased the level of cystatin C and Beta-2 microglobulin (BMG). All other supplements significantly reduced the level of cystatin C than AF; however, this reduction was more pronounced in AF-L-M group. AF + Sor, AF + L-M and AF + Mix equally reduced the BMG level than AF and AF + HSc, however, still higher than control. AF elevated the total cholesterol (TC) and LDL-cholesterol levels. A significant reduction in HDL cholesterol was seen in AF group. Additionally, AF induced pathological alterations in the liver and kidney of exposed rabbits on the other hands, the three additives separately or in mix attenuated the Af-induced alterations. In conclusion, the dietary supplementation of Sor, L-M, Hsc or their mixture was effective in ameliorating the negative effects of AFB1 on liver and kidney function and structure in rabbits with more better improvement obtained by Sor or L-M separately.