Individual and combined effects of crude protein, methionine, and probiotic levels on laying hen productive performance and nitrogen pollution in the manure

Putative Probiotic Ligilactobacillus salivarius Strains Isolated from the Intestines of Meat-Type Pigeon Squabs

This study aims to screen for potential probiotic lactic acid bacteria from the intestines of meat-type pigeon squabs. Ligilactobacillus salivarius YZU37 was identified as the best comprehensive performed strain. Being acid- and bile salt-tolerant, it displayed growth-inhibition activities against Staphylococcus aureus ATCC25923, Escherichia coli ATCC25922, and Salmonella typhimurium SL1344, exhibited sensitivity to 6 commonly used antibiotics, and endowed with good cell surface hydrophobicity, auto-aggregation property, and anti-oxidant activities. Results of in vitro experiments indicated that the bacteriostatic effects of this strain were related to the production of proteinaceous substances that depend on acidic conditions. Whole-genome sequencing of L. salivarius YZU37 was performed to elucidate the genetic basis underlying its probiotic potential. Pangenome analysis of L. salivarius YZU37 and other 212 L. salivarius strains available on NCBI database revealed a pigeon-unique gene coding choloylglycine hydrolase (CGH), which had higher enzyme-substrate binding affinity than that of the common CGH shared by L. salivarius strains of other sources. Annotation of the functional genes in the genome of L. salivarius YZU37 revealed genes involved in responses to acid, bile salt, heat, cold, heavy metal, and oxidative stresses. The whole genome analysis also revealed the absence of virulence and toxin genes and the presence of 65 genes distributed under 4 CAZymes classes, 2 CRISPR-cas regions, and 3 enterolysin A clusters which may confer the acid-dependent antimicrobial potential of L. salivarius YZU37. Altogether, our results highlighted the probiotic potential of L. salivarius YZU37. Further in vivo investigations are required to elucidate its beneficial effects on pigeons.

Using low-protein diet in egg production for win-win of productivity and environmental benefits should be prudent: Evidence from pilot test

A shortage of feed protein resources restricts poultry productivity. Key strategies to alleviate this problem include improvements to the structure of the gut microbiota by the appropriate intake of high-quality protein, improvements to the comprehensive protein utilization rate, and reducing the consumption of protein raw materials. In addition, damage to the environment caused by nitrogen emissions needs to be reduced. The aim of the study was to evaluate the effects of dietary protein levels on laying performance, host metabolism, ovarian health, nitrogen emissions, and the gut microbial structure and function of laying hens. In total, 360 hens at the age of 38 weeks were randomly allotted four treatments. Each of the groups consisted of nine replicates, with 10 birds per replicate, used for 12 weeks of study. Dietary protein levels of the four groups were 13.85 %, 14.41 %, 15.63 %, and 16.30 %. Results revealed that, compared with the 13.85 % crude protein (CP) group, the 15.63 % CP group experienced significantly enhanced final body weight, average daily gain, egg production, and egg mass. Compared with the 16.30 % CP group, the other groups' serum concentrations of immunoglobulin G (IgG) and immunoglobulin M (IgM) were significantly reduced. Compared with the 16.30 % CP group, the 13.85 % and 15.63 % groups had increased CP utilization rates but reduced nitrogen emission rate, and daily per egg and per kilogram egg nitrogen emissions rose with increased dietary protein levels. Compared to the 13.85 % and 14.41 % CP groups, the 16.30 % CP group exhibited a significant increase in the expression of genes related to amino acids and carbohydrate metabolic pathways. According to the linear discriminant analysis effect size diagram, the predominant bacteria in the 15.63 % CP group (e.g., Subdoligranulum, and Ruminococcaceae_UCG-013) were significantly related to CP utilization. The results of this study emphasize that production performance is significantly reduced when protein levels are too low, whereas too high protein levels lead to gut microbiota imbalance and a reduction in the utilization efficiency of nutrients. Therefore, on the premise of ensuring the health of hens, the structure of the gut microbiota can be improved by appropriately reducing protein levels, which helps to balance the relationships among host health, productivity, resources, and the environment.

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.

Comparison of the Effects of Feeding Compound Probiotics and Antibiotics on Growth Performance, Gut Microbiota, and Small Intestine Morphology in Yellow-Feather Broilers

This study was devoted to the comparison of the probiotic effect of compound probiotics to antibiotics as a feed additive for chicken. Two hundred and seventy newly hatched yellow-feather broilers were randomly divided into three groups: the control group (Con), probiotics (Pb), and antibiotics group (Ab). The Pb group received compound probiotics (Bifidobacterium, Lactobacillus acidophilus, Streptococcus faecalis, and yeast) via drinking water for 24 days. The Ab group received antibiotics (zinc bacitracin and colistin sulfate) in their diet for 24 days. All broilers were slaughtered on day 42. Compared with the Con group, the body weight was significantly increased on days 13, 28, and 42 in the Pb group (p < 0.05), and markedly increased on day 28 in the Ab group (p < 0.05). Compared with the Ab group, the body weight of the broilers in the Pb group increased significantly on day 13 (p < 0.05). Compared to the Con and Pb groups, the antibiotics treatment reduced the feed intake (p < 0.05), but there was no significant difference in the feed conversion ratio between the Ab and Pb groups (p > 0.05). The feed conversion ratio of the broilers treated with antibiotics or probiotics significantly decreased compared to the Con group (p < 0.05). The depth of duodenum, jejunum, and ileum crypts in the Pb group decreased significantly compared to the Con and Ab group (p < 0.05). The ratio of the villi length to crypt depth of duodenum, jejunum, and ileum epithelium was significantly increased in the Pb group compared to the Con group (p < 0.05). The genera Bacteroides and Barnesiella were the most significantly enriched bacteria in the Ab and Pb groups, respectively (p < 0.05). The expression of the genes related to antibiotic resistance was significantly decreased in the Pb group compared to the Ab group (p < 0.05). Although both compound probiotics and antibiotics can improve growth performance, antibiotics increased the abundance of harmful bacteria and drug-resistant genes, while probiotics increased Barnesiella abundance, which is related to a decrease in the drug-resistant gene expression. Moreover, the probiotics treatment improved small intestinal morphology and fecal emissions, while antibiotics have no significant effect on these indicators, indicating a bright future for probiotics as an alternative to feed antibiotics in the yellow-feather broiler industry.

Pathogen inhibition and immunomodulation effects of probiotics and prebiotics against Salmonella spp. in chicken

This research investigated the effect of probiotics and prebiotics on the control of Salmonella spp. isolated from chicken. One hundred and eleven bacterial isolates were recovered from different chicken farms, and nine Salmonella isolates were detected with 8%. The serogroup analysis of nine Salmonella isolates showed three different groups identified as (4) S. enteridits, (3) S. typhimurium, and (2) untyped group. Identified Salmonella positive using PCR and genus-specific primer OMPCF (outer membrane protein reverse) with a target size of 204bp. The results of Salmonella enteridities with target size are also 304bp and target 401bp for Salmonella typhimurium.In the experiment, one hundred chicks were grouped into five groups (1, 2, 3,4&5) containing 20 broiler chicks. The broilers of groups (1, 2, 3, 4 & 5) were inoculated orally with a dose of 1 × 108 cfu nalidixic acid-resistant Salmonella enteridities. Group (1) is a control group, group (2) is not treated, group (3) is treated with B. Subtilis natto (1 ×108), group (4) is treated with Levoxyl, and group (5) is treated with panflor. The experiment results significantly increased the survival percentage against those challenged with a virulent strain of nalidixic acid probiotics and prebiotics significantly increases probiotics and prebiotics. The oral application significantly the survival percentage against challenges with a virulent strain of nalidixic acid-resistant Salmonella spp. Probiotics and prebiotics increase body weight gain and feed conversion rate (FCR). Effect of probiotic (Baccilus subtilis) on Salmonella spp. activity, the best result of B.subtilis is 1× 108 has been shown to reduce the growth of the microorganism under study (S. typimurium - S. enterditis).

Probiotics in Poultry Nutrition as a Natural Alternative for Antibiotics

Since the early 1950s, antibiotics have been used in poultry for improving feed efficiency and growth performance. Nevertheless, various side effects have appeared, such as antibiotic resistance, antibiotic residues in eggs and meat, and imbalance of beneficial intestinal bacteria. Consequently, it is essential to find other alternatives that include probiotics that improve poultry production. Probiotics are live microorganisms administered in adequate doses and improve host health. Probiotics are available to be used as feed additives, increasing the availability of the nutrients for enhanced growth by digesting the feed properly. Immunity and meat and egg quality can be improved by supplementation of probiotics in poultry feed. Furthermore, the major reason for using probiotics as feed additives is that they can compete with various infectious diseases causing pathogens in poultry's gastrointestinal tract. Hence, this chapter focuses on the types and mechanisms of action of probiotics and their benefits, by feed supplementation, for poultry health and production.

Choline Chloride Induces Growth Performance of Indian Major Carps and Air-Breathing Fish Species with an Outcome of Quality Food-Fish under a Semi-Intensive Culture System: A Biochemical Investigation

The present study was intended to determine the possible influences of direct field application of choline chloride into pond water in addition to farm-made-aqua-feed under a semi-intensive culture system on the growth and biochemical parameters of two Indian major carps (IMCs), Catla catla (Catla) and Labeo rohita (Rahu), and two air-breathing species, Clarias batrachus (Magur) and Anabas testudineus (Koi), cultured in a ratio of 2:5:1:1 (Catla/Rahu/Magur/Koi) in three experimental ponds for a period of 90 days during the breeding season (June to August). Results were compared with control (C: fed only with farm-made-aqua-feed) and treatment (T: P1 and P2: farm-made-aqua-feed plus choline chloride into pond water directly at the rate of 350 g bigha^-1 fortnightly or 350 g per 1600 square meter fortnightly). A significant increasing trend was observed in the growth parameters including total length-final (TLF), standard length-final (SLF), mean weight-final (MWF), % gain of mean total length (MTL), % gain of mean standard length (MSL), % weight gain (WG), specific growth rate (SGR) % per day, and survivability %. However, a reverse pattern was noticed in the food conversion ratio (FCR) both in IMCs and air-breathing fish species under choline supplementation. Serum biochemical responses, e.g., total protein (PRO), lactate dehydrogenase (LDH), glucose (GLU), and calcium (Ca) showed significant enhancement, and alkaline phosphatase (ALP), alanine amino transaminase (ALT), aspartate amino transaminase (AST), cholesterol (CHOLES), and triglycerides (Trig) showed gradual significant reduction during the breeding season under choline exposure. Treated fishes showed prevention from liver dysfunction and fatty liver formation, and increased body crude protein content. Results indicated favorable growth and yield, which may benefit fish farmers during their culture practices, and the output fish species under choline supplementation resulted in quality food-fish for human consumption.

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.

Dietary strategies to alleviate high-stocking-density-induced stress in broiler chickens – a comprehensive review

Stocking broilers at a high density has been a strategy to optimize the area of the cage and hence increase the efficiency of broiler production. If the environmental (microclimate) conditions and rearing management are not properly managed, stocking broilers at a high density may, however, result in stressful conditions that are harmful for the production, health and welfare of broilers. To ameliorate these unfavorable effects of overcrowding stress, dietary interventions have been conducted. Probiotics, prebiotics, synbiotics, plant-derived products, vitamins, propolis, amino acids, fatty acids, etc. have been supplemented in diets to deal with the harmful impact of stress induced by a high stocking density of broilers. This review covers the detrimental effects of overcrowding-induced stress on broiler development and attempts to ameliorate those negative effects by dietary interventions.

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.

Blood biochemical parameters and organs development of brown layers fed reduced dietary protein levels in two rearing systems

Objective

An experiment was conducted to evaluate the effect of different levels of crude protein (CP) and two rearing systems (cage and floor), on blood parameters and digestive and reproductive organ development of brown laying hens.

Methods

A total of 400 Hisex Brown laying hens between 30 and 45 weeks of age were distributed in a completely randomized design and a 2×4 factorial arrangement, with main effects including two rearing systems (cage and floor) and levels of CP (140, 150, 160, and 180 g/kg), in a total of eight treatments and five replicates of 10 birds each with initial body weight of 1,877 g (laying hen in cage) and 1,866 g (laying hens in floor). The parameters evaluated were plasma total protein, albumin, uric acid, total cholesterol, relative weights of oviduct, abdominal fat, liver, gizzard, crest and dewlap, length of small intestine and oviduct.

Results

The blood parameters were similar in birds reared in cage and floor systems. The birds reared on the floor showed greater small intestine and oviduct weight (%) and lower liver and pancreas weight (%). A significant interaction was observed between factors for the relative gizzard, crest and dewlap weight, serum protein, uric acid, and total cholesterol (P<0.05). The diets with 140 g/kg CP resulted in lower serum protein and lower cholesterol in birds reared in floor system, while birds reared in cage system showed no effect of CP on both parameters. Birds reared in cage and fed with 140 and 150 g/kg CP presented lower uric acid. The group of birds reared in floor system fed 180 g/kg had greater uric acid.

Conclusion

The dietary protein level can be reduced up to 140 g/kg for Hisex Brown hens (30 to 45 weeks of age) without an important effect on metabolic profile and organ development in both rearing systems.

Effect of graded levels of dietary Bacillus toyonensis and Bifidobacterium bifidum supplementation on growth, carcass traits and ileal histomorphometry and microbiota of growing quails

This experiment investigated the role of graded dietary levels of two probiotic strains (Bacillus toyonensis; BT and Bifidobacterium bifidum; BB) on the growth rate, carcass traits, physiological and histological aspects of growing Japanese quail. One thousand and three hundred sixty one-day-old un-sexed Japanese quail chicks were distributed randomly into ten groups. The 1st group served as a control and fed the basal diet without supplement while the 2nd, 3rd, 4th and 5th groups received the control diet supplemented with 0.05, 0.075, 0.10 and 0.125% BT, respectively. The 6th group fed the control diet plus 0.10% BB while the remaining groups (7th to 10th) received the basal diet incorporated with the previous levels of BT rich with 0.05% BB. Dietary supplementation of BT and/or BB increased body weight and gain; however, feed intake and feed conversion were not affected. Amylase activity was significantly elevated in 5th, 7th and 9th groups, while lipase activity was improved in all treatment groups except 3rd and 6th groups. Results obtained concluded that dietary supplementation of BT with or without BB is useful for performance, digestive enzyme activities, blood cholesterols, antioxidant status and ileal histomorphometry and microbiota of growing Japanese quail.

Preventive antimicrobial action and tissue architecture ameliorations of Bacillus subtilis in challenged broilers

Background and Aim:

Probiotics improve intestinal balance through bacterial antagonism and competitive exclusion. This study aimed to investigate the in vitro antimicrobial activity, as well as the in vivo preventive, immunological, productive, and histopathological modifications produced by probiotic Bacillus subtilis.

Materials and Methods:

The in vitro antimicrobial activities of B. subtilis (5×10⁶ CFU/g; 0.5, 1.0*, 1.5, and 2.0 g/L) were tested against Escherichia coli O157: H7, Salmonella Typhimurium, Candida albicans, and Trichophyton mentagrophytes after exposure times of 0.25, 0.5, 1, and 2 h using minimal inhibitory concentration procedures. A total of 320 1-day-old female Ross broiler chickens were divided into five groups. Four out of the five groups were supplemented with 0.5, 1.0*, 1.5, and 2.0 g/L probiotic B. subtilis from the age of 1 day old. Supplemented 14-day-old broiler chickens were challenged with only E. coli O157: H7 (4.5×10¹² CFU/mL) and S. Typhimurium (1.2×10⁷ CFU/mL). A total of 2461 samples (256 microbial-probiotic mixtures, 315 sera, 315 duodenal swabs, and 1575 organs) were collected.

Results:

The in vitro results revealed highly significant (p<0.001) killing rates at all-time points in 2.0 g/L B. subtilis: 99.9%, 90.0%, 95.6%, and 98.8% against E. coli, S. Typhimurium, C. albicans, and T. mentagrophytes, respectively. Broilers supplemented with 1.5 and 2.0 g/L B. subtilis revealed highly significant increases (p<0.01) in body weights, weight gains, carcass weights, edible organs’ weights, immune organs’ weights, biochemical profile, and immunoglobulin concentrations, as well as highly significant declines (p<0.01) in total bacterial, Enterobacteriaceae, and Salmonella counts. Histopathological photomicrographs revealed pronounced improvements and near-normal pictures of the livers and hearts of broilers with lymphoid hyperplasia in the bursa of Fabricius, thymus, and spleen after supplementation with 2.0 g/L B. subtilis.

Conclusion:

The studies revealed that 1.5-2.0 g of probiotic B. subtilis at a concentration of 5×10⁶ CFU/g/L water was able to improve performance, enhance immunity, and tissue architecture, and produce direct antimicrobial actions.

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.

Dietary effect of probiotics and prebiotics on broiler performance, carcass, and immunity

This experiment was carried out to evaluate the effects of dietary addition of probiotics (Protexin) and prebiotics (active MOS, mannan oligosaccharides) on growth performance, carcasses, and antibody titer in broilers. A total number of 360-day-old Ross broiler chicks were randomly divided into 9 groups in a 3 × 3 factorial arrangement. Nine broiler starter (0-21 d) and finisher (21-35 d) diets were formulated by using 3 levels of probiotics (0, 1, and 2 g/kg of feed) and 3 levels of MOS (0, 1, and 1.5 g/kg of feed) and were randomly allotted to 9 groups. Feed intake was not affected by interaction of treatments during all phases (P > 0.05). Feed intake was improved due to the main effect of probiotic (P = 0.0001) or MOS (P = 0.005). No interaction (P > 0.05) was observed for weight gain in the starter, finisher, and overall phases. While, during the starter and finisher phases, weight gain was increased by probiotics (P = 0.028 or 0.04, respectively). Dietary supplementation of MOS improved weight gain (P = 0.01) and feed conversion ratio (FCR) (P = 0.03) during the overall period, but during starter and finisher periods, weight gain and FCR were not affected by prebiotics. Apart from dressing percentage, no interaction or individual effect of probiotics and prebiotics was observed for carcass, breast, thigh, heart, liver, and gizzard weight. Antibody titer for infectious bursal disease (IBD) was improved (P = 0.026) by the interaction effect between probiotics and prebiotics, when compared with the control group. Antibody titer against Newcastle disease (ND) was not affected by probiotics or prebiotics or their interactions (P > 0.05). It could be concluded that supplementation of prebiotics or probiotics can improve the growth performance of broilers. It may also be helpful in improving the antibody titer against IBD in broilers fed antibiotic-free diets.

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.

Probiotics in poultry feed: A comprehensive review

The use of antibiotics to maintain animal well-being, promote growth and improve efficiency has been practised for more than 50 years. However, as early as the 1950s, researchers identified concern on the development of resistant bacteria for the antibiotics streptomycin and tetracycline used in turkeys and broilers respectively. These findings laid the groundwork for agricultural officials to impose stricter regulatory parameters on the use of antibiotics in poultry feeds. Probiotics are live micro-organisms included in the diet of animals as feed additives or supplements. Commonly known as a direct-fed microbial, probiotics provide beneficial properties to the host, primarily through action in the gastrointestinal tract (GIT) of the animal. Supplementation of probiotics in the diet can improve animal health and performance, through contributions to gut health and nutrient use. For instance, supplementation of probiotics has been demonstrated to benefit farm animals in immune modulation, structural modulation and increased cytokine production, which positively affect the intestinal mucosal lining against pathogens. Bacillus subtilis has been a popular bacterium used within the industry and was shown to improve intestinal villus height. Increasing the villus height and structure of the crypts in the GIT allows for the improvement of nutrient digestion and absorption. Tight junctions maintain important defences against pathogenic bacteria and cellular homeostasis. Heat stress can be a major environmental challenge in the poultry industry. Heat stress causes the bird to fluctuate its internal core temperature beyond their comfort zone. To overcome such challenges, poultry will attempt to balance its heat production and dissipation through behavioural and physiological adaptation mechanisms.

Growth, carcass characteristics, meat quality, and microbial aspects of growing quail fed diets enriched with two different types of probiotics (Bacillus toyonensis and Bifidobacterium bifidum)

The present investigation aimed to explore the impact of dietary graded levels of 2 types of probiotic bacteria (Bacillus toyonensis [BT] and Bifidobacterium bifidum [BB]) on growth, carcass traits, meat quality, and bacteriology of growing Japanese quail reared under the cage system. One thousand three hundred sixty Japanese quail day-old chicks were randomly divided into 10 groups (8 replicates each). Birds were fed a basal diet (control, T1) and the basal diet plus 0.05, 0.075, 0.10, and 0.125% BT (T2, T3, T4, and T5, respectively), 0.10% BB (T6), and the same previous doses of BT plus 0.05% BB (T7, T8, T9, and T10, respectively). Results showed a significant (P < 0.001) increase in final BW and weight gain because of probiotic supplementation (except T2 for weight gain). Both feed intake and feed conversion ratio did not differ during the overall experimental period (1–42 D of age) except feed intake that was reduced in T2 and increased in T5 and T9 groups. All carcass traits studied were significantly (P < 0.01) affected by probiotics, and the combination between BT and BB in group T8 increased all studied parameters as compared with the other treatment groups. The quail meat color of redness a∗ and L∗ values, thiobarbituric content, cooking loss, proteolysis, and total coliform were decreased (P < 0.001) by probiotic treatment. In general, supplementing BT, BB, or their combination to the basal diet delayed the proliferation of pathogenic bacteria in the diet and intestine. Using BT and BB as feed supplements enhanced growth performance and meat quality of quails as well as diminished pathogenic bacteria proliferation in their diet and intestine. As per our results, we can recommend the application of T5 and T8 to T10 levels for the best performance, carcass traits, and meat quality of growing quails.

Maternal dietary methionine supplementation influences egg production and the growth performance and meat quality of the offspring

This study aimed to investigate the effects of maternal dietary coated methionine (Met) on egg production and the quality, growth performance, carcass traits, and meat quality of the offspring. In total, 288 female Ross parental chickens were randomly assigned to 3 groups with 3 replicates of 32 chickens each. From week 37 to 46, the hens of different groups were fed diets containing low (0.27% Met), adequate (0.27% Met + 0.1% coated Met) (AM), and high (0.27% Met + 0.2% coated Met) (HM) Met. There was a positive response in laying rate and albumen weight in AM and HM groups. For the offspring at market age, BW, eviscerated weight, and muscle weight were increased in the AM group (P < 0.05), whereas excessive supplementation was proven to be negative with those traits. The meat quality (color, pH, and shear force) of breast muscle was significantly influenced by different supplementation levels. The lightness and yellowness were increased in the HM group (P < 0.05, P < 0.01, respectively), and redness was decreased in the AM group (P < 0.05). A lower pH value occurred in chickens of the HM group (P < 0.05). The expressions of meat quality–related genes were altered in the supplementation groups. The pH-related genes PRDX4 and PRKAG2 were found to be significantly differentially expressed (P < 0.05, P < 0.01, respectively) and consistent with pH changes. The meat color–related gene BCO1 was also differentially expressed (P < 0.01) and showed a corresponding change with yellowness value. Collectively, the best production performance was in the offspring with 0.1% coated Met supplementation (AM group). Supplementation with 0.2% coated Met (HM group) seemed to be excessive, but laying rate was increased in the HM group. Both results of phenotypic measurements and gene expression demonstrated that maternal-coated Met supplementation resulted in fluctuation of some meat quality indices in the offspring, but all values were still within the range found in normal chickens.

Effect of Dietary Protein and Tsaa Levels on Performance, Carcass Traits, Meat Composition and Some Blood Components of Egyptian Geese During the Rearing Period

The present study was performed to investigate the effect of dietary levels of protein, total sulfur amino acids (TSAA), methionine and cystine (M + C) and their interaction on the performance, carcass characteristics, blood components and meat quality of Egyptian geese. A total number of 144 geese at twelve weeks of age were randomly divided into 9 groups (16 birds/each group), each group of birds was sub-divided into 4 replicates, each of 4 birds. There was a significant increase in the bodyweight of geese due to protein and M + C levels (p < 0.01). The studied levels of M + C affected significantly on weight gain of growing geese at the early period of 12-18 wk of age. Feed intake was increased with high dietary levels of CP % or M + C (p < 0.05). There was a significant (p < 0.01) increase in percentages of carcass, liver, dressing, breast and wing with high dietary protein level as compared to a moderate or low level. A high level of dietary protein led to increase in concentrations of total protein and albumin, while total lipids, cholesterol, aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were decreased with increasing level of protein (p < 0.01). Fat percentage of breast muscle was significantly (p < 0.01) decreased with increasing M + C levels. Protein % of breast muscle was increased with increasing protein levels. Finally, it can be concluded that the consumption of diets with high levels of protein or M + C can improve the bodyweight, feed conversion ratio, carcass and meat composition of Egyptian geese during the rearing period (12-24 wk of age).

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

Simple Summary

The current work evaluated the utilization of different sources of methionine either from DL-methionine (DL-Met) or L-methionine (L-Met) using different concentrations of dietary methionine plus cystine (Met + Cyst) in broiler chickens. Results showed that a better edible meat yield could be obtained by supplementing Met + Cyst at the rate of 80% of the digestible lysine.

Abstract

The objective of this work was to evaluate the utilization of methionine from DL-methionine (DL-Met) and L-methionine (L-Met) with different levels of dietary methionine plus cystine (Met + Cyst) in broilers. The experimental diets were formulated by using three levels of Met + Cyst, i.e., 74%, 77% and 80% of digestible lysine. Met + Cyst was provided either from DL-Met or L-Met. A total of 450 day-old broilers were divided into six groups (five replicates of 15 birds each) in a 3 × 2 factorial arrangement under completely randomized design. Weight gain (WG), feed intake (FI) and feed conversion ratio (FCR) was determined. At the end of the experiment (35 days), two birds from each replicate were slaughtered to determine carcass characteristics and serum homocysteine. Results indicate that the combined effect of L-Met and DL-Met significantly affected (p < 0.05) the WG in the starter period and FI in the finisher period. Neither source nor level of methionine influenced (p > 0.05) the FI, WG and FCR of broilers during the starter, finisher or overall phase of growth. The interaction between sources and levels of methionine did not influence (p > 0.05) the feed intake, weight gain and FCR during the overall phase of growth. Source of methionine had no (p > 0.05) effect on carcass characteristics. Methionine levels had a significant effect (p < 0.05) on carcass weight, chest weight and thigh weight. The interaction between sources and levels of methionine had a significant (p < 0.05) effect on the liver weight. The sources of methionine had significant (p < 0.05) effects on the liver and heart weight, while methionine levels significantly influenced (p < 0.05) the liver and gizzard weight. Finally, it was concluded that if DL-Met and L-Met are included in feed at a standard level, they are equally effective as a source of methionine for broilers.

Dietary supplementation of potassium sorbate, hydrated sodium calcium almuniosilicate and methionine enhances growth, antioxidant status and immunity in growing rabbits exposed to aflatoxin B1 in the diet

The present experiment was conducted to evaluate the effect of dietary supplementation with some feed additives (potassium sorbate; Sor, hydrated sodium calcium almuniosilicate; Hsc and L-methionine; L-M) against aflatoxin B1 (AF) toxicity in rabbits. A total of 72 growing rabbits (5-week-old) were distributed into six equal groups (4 replicates with 3 rabbits each). The experimental groups are as follows: control group, AF group (supplemented with AF 0.3 mg/kg diet), AF + Sor group (AF 0.3 mg/kg diet + Sor 2 g/kg diet), AF + Hsc group (AF 0.3 mg/kg diet + Hsc 5 g/kg diet), AF + L-M group (AF 0.3 mg/kg diet + L-M 8 g/kg diet) and AF + Mix group (AF 0.3 mg/kg diet + 2 Sor + 5 Hsc + 8 L-M g/kg diet). Live body weight and weight gain at 13 weeks of age were significantly reduced by AF. Feed intake at 13 weeks of age was decreased in AF, AF + Hsc and AF + Mix compared to the control. AF, AF + Hsc and AF + Mix showed the lowest total antioxidant capacity compared to the control. The highest level of reactive oxygen species and 8-Hydroxy-2-desoxyguanosine was observed in AF group. Using of other supplements with AF increased immunoglobulinM than AF alone. In conclusion, dietary supplementation of Sor, L-M, Hsc or their mixture was effective in reducing the adverse effects of AF on performance, antioxidant and immune status of rabbits with more better improvement obtained by Sor or L-M separately.

Impact of restricting feed and probiotic supplementation on growth performance, mortality and carcass traits of meat-type quails

The objective of this study was to evaluate the effects of quantitative feed restriction, along with dietary supplementation with a probiotic blend (Protexin) as a natural growth promoter, on the performance, water consumption, mortality rate and carcass traits of meat-type quails. A total of 250 1-day unsexed quails were randomly allocated to five equal groups in a completely randomized design. The first group (A) fed a basal diet without any restriction (24 hr/day); the second group (B1) fed the basal diet for 20 hr/day; the third group (B2) fed the basal diet enriched with probiotic (0.1 g/kg diet) for 20 hr/day; the fourth group (C1) fed the basal diet for 16 hr/day; and the fifth group (C2) fed the basal diet enriched with probiotic (0.1 g/kg diet) for 16 hr/day. Birds were fed ad-libitum from 0-14 days of age, and then the feed restriction regimes started from 14 till 28 days of age. Results showed that quails in the control-group consumed more feed and water than the other treatment groups (p < .01), however their body weights did not differ (p > .05) compared with the other treated groups. The best feed conversion values were achieved in quails supplemented with probiotic blend (B2 and C2) in comparison with the other groups (p < .01). Feeding probiotic had a positive effect on bird health which reduced the mortality rate. Further, mortality rate was significantly reduced (p < .05) by feed restriction, with or without probiotic supplementation. No carcass parameters were significantly affected (p > .05) by treatments. Our results show that quail could be reared under a feed restriction system, for 4-8 hr daily, along with dietary supplementation of probiotic as growth promoter for better growth performance.

Influences of stocking density and dietary probiotic supplementation on growing Japanese quail performance

This study investigated the effects of stocking density and dietary supplementation of probiotic (Lactobacillus) on growth, traits of carcass, lymphoid organs and intestinal microbial count of Japanese quail. Quail chicks (one week old) were randomly allotted to 6 groups in a 2×3 factorial experiment included 2 levels of stocking density (100, and 75 cm2/bird) and 3 levels of probiotic (0.00, 0.02 and 0.04 g/kg diet). Quail reared at 100 cm2/ bird showed significantly the highest body weight and daily gain. Quail reared at 75 cm2/ bird had significantly the lower average of feed consumption and the best ratio of feed conversion. Increasing level of probiotic up to 0.04 g/kg led to a significant decrease in dressing percentage by about 2.7 % compared to the control. Interaction effect was insignificant on carcass traits studied except for liver percentage which was significantly higher for birds fed diet supplemented with probiotic at 0.04 g/kg of diet and reared at 100 cm2/bird. Rearing quail at 100 cm2/bird stocking density significantly increased bursa weight. Birds fed diet supplemented with probiotic at 0.02 g/kg of diet and reared at 100 cm2/bird showed significantly the highest (p = 0.043) spleen weight when compared with the other groups. In conclusion, the low (100 cm2/bird) stocking density was sufficient to give better performance of Japanese quail than the other group. Probiotic supplementation diminished the stressful effect of crowding on growing Japanese quail.

Influences of dietary crude protein and stocking density on growth performance and body measurements of ostrich chicks

Thirty-six African Black ostrich chicks were used to investigate the effects of dietary crude protein (CP) levels (180, 210 and 240 g/kg), stocking density (4.5 and 3 m2/bird) and their interactions. A factorial arrangement was used to examine the impact of treatments on growth performance and body measurements of ostrich chicks during 2 to 10 weeks of the age. Results indicated that factors studied did not change growth performance traits. The highest value of protein efficiency ratio was observed in ostrich chicks fed diet contained 240 g/kg diet. Birds fed diet contained 240 g CP /kg diet and kept at stocking density of 3 m2 per bird had numerically the highest protein efficiency ratio. Shank girth and tibiotarsus length decreased with increasing dietary CP level. Stocking density did not change values of body measurements, except tibiotarsus length at 6 weeks of age, which increased in birds kept at the lower density than the higher. Body height at 10 weeks of age was significantly affected by the interactions between dietary CP and stocking density. In conclusion, results affirmed that ostrich chicks can grow on diets containing low levels of CP (180-210 g/kg). Our results provide a comprehensive set of morphometric data for ostrich chicks as affected by the factors studied.