EFSA and EMA have jointly reviewed measures taken in the EU to reduce the need for and use of antimicrobials in food-producing animals, and the resultant impacts on antimicrobial resistance (AMR). Reduction strategies have been implemented successfully in some Member States. Such strategies include national reduction targets, benchmarking of antimicrobial use, controls on prescribing and restrictions on use of specific critically important antimicrobials, together with improvements to animal husbandry and disease prevention and control measures. Due to the multiplicity of factors contributing to AMR, the impact of any single measure is difficult to quantify, although there is evidence of an association between reduction in antimicrobial use and reduced AMR. To minimise antimicrobial use, a multifaceted integrated approach should be implemented, adapted to local circumstances. Recommended options (non-prioritised) include: development of national strategies; harmonised systems for monitoring antimicrobial use and AMR development; establishing national targets for antimicrobial use reduction; use of on-farm health plans; increasing the responsibility of veterinarians for antimicrobial prescribing; training, education and raising public awareness; increasing the availability of rapid and reliable diagnostics; improving husbandry and management procedures for disease prevention and control; rethinking livestock production systems to reduce inherent disease risk. A limited number of studies provide robust evidence of alternatives to antimicrobials that positively influence health parameters. Possible alternatives include probiotics and prebiotics, competitive exclusion, bacteriophages, immunomodulators, organic acids and teat sealants. Development of a legislative framework that permits the use of specific products as alternatives should be considered. Further research to evaluate the potential of alternative farming systems on reducing AMR is also recommended. Animals suffering from bacterial infections should only be treated with antimicrobials based on veterinary diagnosis and prescription. Options should be reviewed to phase out most preventive use of antimicrobials and to reduce and refine metaphylaxis by applying recognised alternative measures.

https://hal-anses.archives-ouvertes.fr/anses-01634046/document

EMA and EFSA Joint Scientific Opinion on measures to reduce the need to use antimicrobial agents in animal husbandry in the European Union, and the resulting impacts on food safety (RONAFA)

The major goals of the poultry industry are to increase the carcass yield and to reduce carcass fatness, mainly the abdominal fat pad. The increase in poultry meat consumption has guided the selection process toward fast-growing broilers with a reduced feed conversion ratio. Intensive selection has led to great improvements in economic traits such as body weight gain, feed efficiency, and breast yield to meet the demands of consumers, but modern commercial chickens exhibit excessive fat accumulation in the abdomen area. However, dietary composition and feeding strategies may offer practical and efficient solutions for reducing body fat deposition in modern poultry strains. Thus, the regulation of lipid metabolism to reduce the abdominal fat content based on dietary composition and feeding strategy, as well as elucidating their effects on the key enzymes associated with lipid metabolism, could facilitate the production of lean meat and help to understand the fat-lowering effects of diet and different feeding strategies.

https://e-sc.org/upload/ajas/pdf/ajas-27-7-1057-20.pdf

Nutritional Factors Affecting Abdominal Fat Deposition in Poultry: A Review

The worldwide resurgence of bed bugs [both Cimex lectularius L. and Cimex hemipterus (F.)] over the past two decades is believed in large part to be due to the development of insecticide resistance. The transcriptomic and genomic studies since 2010, as well as morphological, biochemical and behavioral studies, have helped insecticide resistance research on bed bugs. Multiple resistance mechanisms, including penetration resistance through thickening or remodelling of the cuticle, metabolic resistance by increased activities of detoxification enzymes (e.g. cytochrome P450 monooxygenases and esterases), and knockdown resistance by kdr mutations, have been experimentally identified as conferring insecticide resistance in bed bugs. Other candidate resistance mechanisms, including behavioral resistance, some types of physiological resistance (e.g. increasing activities of esterases by point mutations, glutathione S-transferase, target site insensitivity including altered AChEs, GABA receptor insensitivity and altered nAChRs), symbiont-mediated resistance and other potential, yet undiscovered mechanisms may exist. This article reviews recent studies of resistance mechanisms and the genes governing insecticide resistance, potential candidate resistance mechanisms, and methods of monitoring insecticide resistance in bed bugs. This article provides an insight into the knowledge essential for the development of both insecticide resistance management (IRM) and integrated pest management (IPM) strategies for successful bed bug management.

/pdf/insecticide-resistance-and-resistance-mechanisms-in-bed-bugs-nwara6qcrx.pdf

Insecticide resistance and resistance mechanisms in bed bugs, Cimex spp. (Hemiptera: Cimicidae)

Towards the control of necrotic enteritis in broiler chickens with in-feed antibiotics phasing-out worldwide

Recently, antibiotics have been withdrawn from some poultry diets; leaving the birds at risk for increased incidence of dysbacteriosis and disease. Furthermore, mortalities occurring from disease contribute between 10 to 20% of production cost in developed countries. Currently, numerous feed supplements are being proposed as effective antibiotic alternatives in poultry diets, such as prebiotics, probiotics, acidic compounds, competitive exclusion products, herbs, essential oils, and bacteriophages. However, acidic compounds consisting of organic acids show promise as antibiotic alternatives. Organic acids have demonstrated the capability to enhance poultry performance by altering the pH of the gastrointestinal tract (GIT) and consequently changing the composition of the microbiome. In addition, organic acids, by altering the composition of the microbiome, protect poultry from pH-sensitive pathogens. Protection is further provided to poultry by the ability of organic acids to potentially enhance the morphology and physiology of the GIT and the immune system. Thus, the objective of the current review is to provide an understanding of the effects organic acids have on the microbiome of poultry and the effect those changes have on the prevalence of pathogens and diseases in poultry. From data reviewed, it can be concluded that the efficacy of organic acids on shifting microbiome composition is limited to the time of administration, the composition of the organic acid product, and the current health conditions of poultry.

/pdf/organic-acids-and-potential-for-modifying-the-avian-44khnqta3p.pdf

Organic Acids and Potential for Modifying the Avian Gastrointestinal Tract and Reducing Pathogens and Disease

For several decades, antibiotics and chemotherapeutics in prophylactic doses have been used in poultry diet to improve their welfare and to obtain economic benefits in terms of improved animal performance and reduced medication costs. With increasing concerns about antibiotic resistance, there is increasing interest in finding alternatives to antibiotics for poultry production. Prebiotics are one of the alternatives that can improve poultry performance through altering gut microflora. Furthermore, high protein prices and environmental concerns have pressured the industry to search for methods for reducing dietary protein levels.

The Application of Prebiotics in Poultry Production

In this experiment, the effect of hydroalcoholic grape seed extract (GSE) and vitamin C feed supplementation on some blood parameters and heat shock protein 70 ( HSP70 gene) expression of broiler chickens suffering from chronic heat stress was investigated. Experimental diets included control diet (with no additive), 3 levels of GSE (150, 300, 450 mg/kg), and one level of vitamin C (300 mg/kg). Each diet was fed to 5 replicates of 12 male chicks each, from d 1 to 42. The birds suffered from chronic daily heat stress under 34±1°C temperature with 65 to 70% relative humidity for 5 h from 29 to 42 d of age. Results showed that 300 mg/kg GSE supplementation increased body weight of broilers both before and after heat stress condition (at 28 and 42 d, respectively). Also, birds fed 300 mg GSE/kg diet had higher European production efficiency factor during the whole period of the experiment. Supplementation of GSE decreased the concentration of serum glucose at 28 and 42 d; at 42 d (during heat stress condition) and at 450 mg/kg diet it decreased cholesterol, triglyceride, lowand very low density lipoprotein concentration of serum blood. Vitamin C supplementation decreased serum cholesterol concentration of broilers suffering from heat stress. HSP70 gene expression in heart and liver of broilers reduced by GSE and vitamin C supplementation pre- and during chronic heat stress condition.

The Effect of Grape Seed Extract and Vitamin C Feed Supplementation on Some Blood Parameters and HSP70 Gene Expression of Broiler Chickens Suffering from Chronic Heat Stress

In a completely randomized design the effects of a multi-enzyme (Endo-feed-W) supplementation on performance, carcass characteristics and some blood parameters of Cobb 500 broilers fed on corn - soybean meal-wheat diets were studied. The enzyme levels added to the diets were 0.00% (control) and 500mg kg DM. Enzyme supplementation significantly improved body weight gain, feed to gain ratio, relative -1 growth, energy and protein efficiency from 11-28 d of age. Adding enzyme significantly increased body weight gain, decreased feed intake and improved feed to gain ratio, energy and protein efficiency from 29-44 d of age (p<0.05). Body weight gain, feed intake, relative growth, energy and protein efficiency was increased and feed to gain ratio was decreased by enzyme supplementation from 29-44 d (p<0.05). Enzyme addition significantly increased carcass and thigh percentages at 44 d of age. Adding enzyme significantly increased the concentration of blood triiodothyronine (T ) at 28 and 42 d and reduced the concentration of blood thyroxin 3 (T ) at 42 d of age. Enzyme inclusion increased the concentration of blood total cholesterol at 10, 28 and 42 4 d of age, however HDL-cholesterol and triglyceride concentrations increased at d 10 and 42 (p<0.05). The concentration of blood uric acid was significantly decreased at d 28 and 42 in broilers fed enzyme supplemented diets.

/pdf/the-effects-of-enzyme-supplementation-on-performance-carcass-349fpibaxj.pdf

The Effects of Enzyme Supplementation on Performance, Carcass Characteristics and Some Blood Parameters of Broilers Fed on Corn-Soybean Meal-Wheat Diets

Problem statement: Endogenous enzymes of broilers cannot adequately digest nonstarch
polysaccharides and subsequently the ingestion of high levels of soluble NSP leads to increased digesta
viscosity and reduced nutrient digestibility and absorption. Supplementation of NSPs degrading
enzymes may remove the anti nutritive effects of NSPs and release some nutrients (starch, protein)
from these elements. Therefore, in a completely randomized design the effects of a multi-enzyme
(Endofeed W produced from Aspergillus niger, with minimum activity of 2250 u g−1 xylanase and
700 u g−1 β-glucanase) supplementation on performance, carcass characteristics, carcass composition
and some blood parameters in Cobb 500 broilers fed on corn-soybean meal-wheat diets were studied.
Approach: A total of 150 one-day-old broiler chicks (Cobb 500) were used in a completely
randomized design with 2 treatments and 3 replicates. The main ingeridients of diets included corn,
soybean meal and wheat. The enzyme levels added to the diets were 0.00 (control) and 500 mg kg−1
DM. Results: Enzyme supplementation significantly improved relative growth, energy efficiency and
protein efficiency from 11-28 days of age. Adding enzyme significantly decreased body weight gain,
feed intake and improved feed to gain ratio, energy efficiency and protein efficiency from 29-44 days
of age (p<0.05). Relative growth, energy efficiency and protein efficiency was increased and body
weight gain, feed intake and feed to gain ratio was decreased by enzyme supplementation from 1-44
days (p<0.05). Enzyme addition significantly increased carcass and thighs + drumsticks percentages at
44 days of age. Adding enzyme significantly increased the concentration of blood Triiodothyronine
(T3) at 28 and 44 days and reduced the concentration of blood Thyroxine (T4) at 44 days of age.
Enzyme inclusion increased the concentration of blood total cholesterol at 10, 28 and 44 days of age,
however triglyceride concentrations increased at 10 and 44 days (p<0.05). The concentration of blood
uric acid was significantly decreased at 28 and 44 days in broilers fed enzyme supplemented diets.
Conclusion: Results of this study indicated that supplementation diets with 500 mg kg−1 multi-enzyme
(Endofeed W) in corn-soybean meal-wheat based diet improved broiler chickens feed to gain ratio,
carcass yield and it can change the concentrations of thyroid hormones and some metabolites in blood,
but it had not significant effect on carcass composition.

Effects of Enzyme Supplementation on Performance, Carcass characteristics, Carcass Composition and Some Blood Parameters of Broiler Chicken

The effect of energy and protein dilution during 16 to 20 d of age, on performance, carcass characteristics and blood parameters of broiler chickens was studied in a completely randomized design with 3 treatments and 3 replicates in each treatment. A total of 144 mixed-sex chickens (Cobb 500) were randomly allocated to 9 pens. In order to dilute the diets three levels (0, 20 and 40%) of rice hull was used. During the experiment feed intake, body weight gain, feed conversion ratio were measured weekly. The results indicated that dilution of diet from 16 to 20 d of age increased feed intake in this period, but adjusted feed intake (excluded rice hull) was decreased (P<0.05). Restricted bird consumed more feed in the whole period of the experiment (16 to 44 d). With increasing dilution rate during restriction period, body weight gain of chickens decreased in comparison to control group (P<0.05). Due to compensatory growth after restriction period, restricted chickens had higher body weight gain than control groups at 44 d of age. Feed dilution up to 20 percent had not significant effect on feed conversion ratio in the whole period of the experiment. Diet dilution had not significant effect on carcass, breast meat, legs, proventriculus, heart and feet weight proportion. Diet dilution significantly increased gizzard weight proportion, and decreased abdominal fat pad weight, carcass crude fat, and increased carcass crude protein proportion (P<0.05). Feed dilution up to 20% increased HDL and decreased LDL concentration in plasma at 21 d of age. Diet dilution up to 40% decreased the concentrations of cholesterol, triglyceride, plasma T3, and increased the concentrations of uric acid and plasma T4 at 21 d of age (P<0.05). Diet dilution up to 20 percent increased plasma glucose concentration at 42 d of age (P<0.05). The results of the present study indicated that feed dilution with 20% rice hull during 16 to 20 d of age had not adverse effect on broiler performance and it also reduced abdominal fat pad weight and carcass crude fat proportion.

Hosna Hajati

Papers

The Application of Prebiotics in Poultry Production

The Effect of Grape Seed Extract and Vitamin C Feed Supplementation on Some Blood Parameters and HSP70 Gene Expression of Broiler Chickens Suffering from Chronic Heat Stress

The Effects of Enzyme Supplementation on Performance, Carcass Characteristics and Some Blood Parameters of Broilers Fed on Corn-Soybean Meal-Wheat Diets

Effects of Enzyme Supplementation on Performance, Carcass characteristics, Carcass Composition and Some Blood Parameters of Broiler Chicken

Effect of diet dilution at early age on performance, carcass characteristics and blood parameters of broiler chicks