N. Puvača

Beneficial effects of phytoadditives in broiler nutrition

During the past fifteen years, phytoadditives in animal nutrition have attracted attention for their potential role as alternatives to antibiotic growth promoters. The goal of this paper is to review the current scientific data on the use of phytoadditives in broiler nutrition. The efficacy of phytogenic applications in broiler nutrition depends on several factors, such as composition and feed inclusion level of phytogenic preparations, bird genetics, and overall diet composition. Difficulty arises when comparing different studies using phytoadditives due to the large variation in composition and sourcing, thus the potential biological effects of phytogenic compounds may differ. However, a great amount of research data supports a potential role of phytoadditives as natural, non-antibiotic growth promoters in broiler nutrition. The mechanisms behind growth promotion are far from being elucidated, as data on phytoadditive effects on nutrient digestibility, gut function and the immune system are still scarce. Phytogenic intake may certainly depress pathogen growth in the gut, however an understanding of their effects on the complex gut ecosystem is still far from clear. There is insufficient amount of studies describing the effects of phytoadditive dietary intake on carcass meat safety, whereas the beneficial effect of phytogenics on carcass meat quality is very well documented. As the last point of this review, further considerations on the efficient applications of phytoadditive compounds in broiler nutrition are given.

Fatty acid composition and regression prediction of fatty acid concentration in edible chicken tissues

The nutritional benefits of consuming long chain ω-3 polyunsaturated fatty acids (PUFA), which are found predominantly in linseed for example, are well known. The consumption of poultry meat has increased in consumption by 80% in the last three decades. The best method of increasing long chain ω-3 PUFA consumption would be to increase the long chain ω-3 PUFA content in the edible tissues of poultry aimed for human diets. It has been shown that heart and blood vessel diseases, as well as the occurrence of atherosclerosis are a direct consequence of consuming products of animal origin in human nutrition which contain a high content of lipids rich in saturated fatty acids (SFA), which are the main causes of these diseases. For these reasons healthy foods enriched in PUFAs, particularly ω-3 fatty acids, have gained high importance because of their beneficial effects on human health. Apart from the importance of being able to predict chicken carcass conformation it is also necessary to calculate the required level of fatty acids in the chicken diet that are incorporated into the edible tissues. Regression analysis is most often used for this prediction. The goal in regression analysis is to create a mathematical model that can be used to predict the values of a dependent variable based upon the values of an independent variable. The aim of this paper is to show possible solutions for broiler edible tissue enrichment with ω-3 fatty acids from linseed, and to give possible solutions to the inclusion level of fatty acids in the diets using regression analyses.

Spices and herbs in broilers nutrition: Effects of garlic ( Allium sativum L.) on broiler chicken production

The aim of this review paper is to show the most important bioactive compounds of garlic (Allium sativum L.), modes of action of garlic powder and its effects on broiler chicken productive performance. Allicin is thought to be the principal bioactive compound present in aqueous garlic extract or raw garlic homogenate. When garlic is chopped or crushed, the allinase enzyme present in garlic is activated and acts on alliin to produce allicin. Other important sulphur containing compounds present in garlic are allyl methyl thiosulphonate, 1-propenyl allyl thiosulphonate and γ-L-glutamyl-S-alkyl-L-cysteine. These active compounds are thought to influence feed consumption, feed utilisation, body weight, blood lipid profiles and cholesterol levels in chickens. Biological responses to these bioactive compounds have been attributed to a reduction in risk factors for cardiovascular diseases and cancer, stimulation of immune function, enhanced detoxification of foreign compound, hepatoprotection, antimicrobial, antifungal, anti-inflammatory and antioxidant effects.

Epidemiological significance of poultry litter for spreading the antibiotic-resistant strains of Escherichia coli

The relationship between the use of antibiotics and the presence of antibiotic resistant strains of E. coli, as well as antibiotic residues in poultry litter, mainly due to irregular use of antibiotics is reviewed in the present paper. The aim of this review is to examine the existing problem of poultry waste management and how it can impact agricultural ecology and economy. Actions such as monitoring and reporting incidents of disease outbreaks in the future should provide an outline of how to improve and implement suitable regulations.

Proximate composition, cholesterol concentration and lipid oxidation of meat from chickens fed dietary spice addition (Allium sativum, Piper nigrum, Capsicum annuum)

The effects of supplementing spices, including garlic, black pepper and hot red pepper, in broiler chicken diet on proximate composition, cholesterol content and lipid oxidation of breast and thigh with drumstick meat, skin and liver were investigated. Meat proximate composition included measurements of moisture, protein, fat and ash content. Cholesterol content of tissue homogenates was performed by high-performance liquid chromatography–DAD analyses, while lipid oxidation of white and red meat, as well as liver, was expressed as a concentration of thiobarbituric acid reactive substances (TBARS) (mg malondialdehyde (MDA)/kg tissue). For biological research, eight treatments with a total of 1200 broiler chickens of hybrid line Hubbard were formed, with four replicates. In the control treatment, the chickens were fed with commercial mixtures of standard composition and quality based on corn flour and soybean meal. Experimental treatments were fed with the same commercial mixtures, except with addition of spices. At the end of the experiment and on the basis of gained results, it can be concluded that the chickens in experimental treatments with hot red pepper achieved statistically significantly (P < 0.05) higher final body masses (2460.6 and 2442.4 g) than did the chickens in the control and other treatments. Black pepper showed a positive and significant (P < 0.05) influence on improving the protein content in breast meat (24 g/100 g), hot red pepper lowered the cholesterol concentrations in meat (24.7 g/100 g in red meat), skin (87.4 g/100 g) and liver (263.1 g/100 g), while black pepper significantly (P < 0.05) reduced lipid oxidation in breast (0.05 mg MDA/kg tissue) and thigh with drumstick (0.12 mg MDA/kg tissue). On the basis of obtained findings, it can be concluded that the dietary spice herbs had a positive influence on a proximate composition of chicken meat, cholesterol concentrations and lipid oxidation process.

Spices and herbs in broilers nutrition: hot red pepper ( Capsicum annuum L.) and its mode of action

Spices, herbs and medicinal plants as a feed supplements present promising alternatives to antibiotic growth promoters due to their high content of bioactive substances. A large number of experiments have confirmed a wide range of activities of spices in poultry nutrition such as stimulation of feed intake, antimicrobial, antioxidative and coccidiostat stimulation, increase of body weight gain, lowering the mortality rate and improvement of the blood and tissue lipid profile. The present paper gives a review on the characteristics of hot red pepper and its mode of action in broilers nutrition.

Effects of dietary garlic addition on productive performance and blood lipid profile of broiler chickens.

The aim of this study was to investigate the effect of dietary garlic powder n addition on productive performance and blood lipid status of broiler chicken. n At the beginning of experiment, three treatments of 150 one day old broiler n chickens of hybrid line Hubbard per treatment, on a total of 450 chickens n were formed. Every treatment was divided in four groups which represents four n replicates of the experiment. Control treatment (T1) was fed with mixtures n without addition of garlic powder, while experimental treatments were fed n with addition of 0.5% (T2) and 1.0% (T3) of dietary garlic powder, n respectively. Experiment lasted 42 days. After the completion of experimental n period the highest achieved body weight of chicken was at treatment T2 n (2371.1g) which was followed by treatment T3 (2336.1 g) with statistically n significant differences (p<0.05) compared to control treatment. For the n entire experimental period, feed conversion ratio was lowest in treatment T2 n (1.8 kg/kg) and the highest in control treatment T1 (2.1 kg/kg), without n statistically significant (p>0.05) differences. Addition of garlic powder led n to a statistically significant (p<0.05) increase in values of EBI in compare n to a control treatment T1. The highest mortality rate (5.1 %) and the lowest n EBI (220.4 %) were recorded in control treatment. Addition of garlic powder n in the amount of 1.0% (T3) significantly (p<0.05) decreased LDL n concentrations in blood serum. The lowest concentration of total cholesterol n was recorded at treatment T2 (p<0.05). The highest concentration of HDL (44.8 n and 39.6 mg/dl) was recorded in treatments T3 and T2. It could be concluded n that the addition of garlic has positive influence on chicken production and n blood lipid status, but the further investigation of their mode of action is n still necessary. [Projekat Ministarstva nauke Republike Srbije, br. III n 46012]

Resistance to tetracycline in Escherichia coli isolates from poultry meat: epidemiology, policy and perspective

Food borne transmission of antibiotic resistant strains of Escherichia coli from contaminated food has been recognised as an important hazard for human health in the past few decades and pathogenic strains of E. coli have long been considered as serious zoonotic hazards. Poultry meat is attractive for consumers worldwide, so the measures to preserve the safety of poultry meat are important issues. Tetracyclines are one of the most frequently used antibiotics in poultry farming and are still used in human medicine. The widespread use of tetracyclines in poultry farming may have resulted in the development and transmission of resistance strains from poultry to humans via the food chain. The relationship between the use of tetracyclines and the presence of resistant strains of E. coli in poultry meat, mainly due to the irregular use of antibiotics, is reviewed in this paper. The need for prudent use of antibiotics, particularly those which are used in human medicine is highlighted. Continuous monitoring and reporting on incidents in the future should improve the current regulations.

Chicken genome modelling for the benefit of science

In the early 21st century, genetic modification of chicken primordial germ cells (PGCs) had not been possible before their transfer and recovery through germ line. Chicken PGCs resist deliberate genetic modification, probably by silencing the transgenes in the genome. The use of mobile genetic elements (transposons) in genetic modification and germ-line transmission of PGCs has recently overcome this problem, so that PGCs can be used for further chicken genome modelling in order to study developmental biology, non-coding RNA (ncRNA) functions, viral DNA-RNA hybridisation, silencing of transgene expression, together with epigenetic modification, and gene function. Application of the transposons, viral integrase, zinc-finger nuclease and site-specific recombinase in whole genome elucidation is not sufficient. The chicken PGCs can be used as a model of choice to establish a new generation of methodology for genome modelling. For this purpose the livesome vectors are proposed.

Influence of herbal drugs in broiler chicken nutrition on primal carcass cuts quality assessments

Aim of this investigation was to determine the effects of herbal drugs such as garlic, black pepper and hot red pepper in broiler chicken nutrition on carcass primal cuts quality. Total of 1200 one-day old Hubbard broilers were totally randomly distributed into eight dietary treatments with four replicates each. Chicks were fed with three dietary mixtures: starter, grower and finisher. Dietary mixtures in the experiments were as follows: T1 (Control diet), T2 (Garlic powder 0.5 g/100g), T3 (Garlic powder 1.0 g/100g), T4 (Black pepper powder 0.5 g/100g), T5 (Black pepper powder 1.0 g/100g), T6 (Hot red pepper 0.5 g/100g), T7 (Hot red pepper 1.0 g/100g ) and T8 (Mixture of spices in ratio of 1:1:1 in total amount of 0.5 g/100g). Addition of herbal drugs had significant (p 0.05), while significant differences in the share of wings and beck (p<0.05) were recorded under the influence of added herbal drugs. It can be concluded that the addition of garlic, black pepper and hot red pepper in broiler chicken nutrition showed positive influence on chicken carcass quality.