Effects of Essential Oils and Benzoic Acid on Broiler Performance and Gut Microflora A.c. Pappas, K. C. Mountzouris, K. Fegeros and G. Zervas

The concerns about possible antibiotic residues and disease resistance have given rise to great caution in the use of antibiotics in the animal industry and led to the removal of antimicrobial growth promoters from the diets. Among suitable natural alternatives, essential oils have gained considerable attention. Dietary acidification may be another alternative to antimicrobial growth promoters. Organic acids can positively affect performance possibly due to inhibition of intestinal bacteria competing with the host for available nutrients and due to reduction of toxic bacterial metabolites. In poultry production, organic acids are also used to sanitize the feed, considering problems with salmonella infections. Addition of essential oils and organic acids to poultry diets has been studied with varying and conflicting results. The aim of the present study was to investigate the effect of an essential oil blend (EO) and benzoic acid on broiler performance, carcass characteristics and caecal microflora composition. One thousand male and female Cobb 500 chickens were used in total. There were eight replicates (four for males and four for females) for each one of the following five dietary treatments: T1 (basal diet with no added EO or benzoic acid), T2 (T1 with addition of 100 ppm EO), T3 (T1 with addition of 50 ppm EO and 250 ppm benzoic acid), T4 (T1 with addition of 25 ppm EO and 250 ppm benzoic acid) and T5 (T1 with addition of 50 ppm EO and 125 ppm benzoic acid). Chicken performance was measured at weekly intervals. At the end of week four, eight chickens per treatment were sacrificed for determination of caecal microflora composition. At the end of the experiment (week six), 16 chickens per treatment were slaughtered, plucked and eviscerated for carcass yield determination. Dietary supplementation of each of the additives examined did not significantly affect chicken body weight, feed conversion ratio or mortality. Treatments did not significantly affect carcass or breast weight. The population of total aerobes, coliforms, total anaerobes, lactic acid bacteria, Streptococcus spp, Clostridium spp and Clostridium perfringens was unaffected by dietary treatments. Under the experimental conditions of this study, none of the examined feed additives nor their combinations had a significant beneficial effect compared to the unsupplemented controls. Essential oils as well as organic acids and their salts are known for their effect on gut microflora and have been used as alternatives to antibiotic growth promoters following a ban on their use in animal nutrition. It is highly probable that factors such as good hygiene, good health and optimal rearing of broilers, such as those in the present study, might have masked the potential effect of the dietary treatments. APPLYING HACCP SYSTEM AT AN ESTABLISHMENT PRODUCING PELLETED COMPOUND FEEDS. ΙΙ. OBSERVATIONS ON PHYSICOCHEMICAL AND MICROBIOLOGICAL PARAMETERS OF ANIMAL FEEDS PARAMITHIOTIS, S., PAPPA, A.M., DROSINOS, E.H. and ZOIOPOULOS, P.E. 1. Laboratory of Animal Production, Department of Administration of Agricultural Products and Food Enterprises, School of Management of Natural Resources and Enterprises, University of Ioannina, 2 Seferi Str., Agrinio, 30100, Greece 2. Laboratory of Food Quality Control and Hygiene, Department of Food Science and Technology, Agricultural University of Athens, 75 Iera Odos Str., Votanikos, Athens 11855, Greece. The present work constitutes a study to research information on data related to the hygiene of animal feeds. This investigation is based on the study of physicochemical and microbiological parameters of raw materials, premixes and compound feeds at different stages of the production process at an enterprise producing animal feeds, with a view to validating the food safety management system based on Hazard Analysis Critical Control Points (HACCP) principles. Three series of samples of 25 feeds (75 samples in total) were obtained in monthly intervals from a medium-scale feed manufacturer’s enterprise. The samples consisted of five compound feeds in loose (at the mixer) or pelleted form, as well as 11 raw materials and four premixes used for their production. The analyses (825 in total) included measurements of water activity (αw), pH, Total Bacterial Count (TBC), yeast and fungi, Enterobacteriaceae, coliforms, coagulase-positive staphylococci, E. coli, detection of Salmonella spp., Listeria spp. and determination of aflatoxin Β1. Water activity was maximum (0.686) for wheat bran and minimum for dried citrus pulp. The measurement of αw ranged from 0.578 to 0.648 and 0.616 to 0.741, whereas pH ranged from 5.8 to 6.2 and 5.8 to 6.4 in loose and pelleted compound feeds, respectively. TBC in loose feeds ranged from 4.4 to 6.3; yeast –moulds 3.3 to 4.1, Enterobacteriaceae 3.2 to 4.7 and coliforms 3.2 to 4.9 log cfu g. Microbiological counts of pelleted compound feeds were remarkably lower for all the variables studied, compared to those of feeds in loose form. TBC in pelleted feeds ranged from <2.0 to 3.7 log cfu g. Wheat bran was the raw material with the highest microbial population. Coagulase-positive staphylococci were below the detection limit (<2.0 cfu g) and aflatoxin Β1 were not detected in any of the 75 samples and, furthermore, values for other variables were found to be negligible. Escherichia coli were detected in soybean meal, sunflower meal and in three out of 30 samples of compound feeds. Listeria monocytogenes and Salmonella spp. were not detected in any of the samples studied. The findings of the present work lead to the conclusion that the application of a food safety management system (HACCP) was implemented effectively in the feed enterprise, providing information that can be used for comparison purposes for the evaluation of systems in other similar feed manufactures. Moreover, with the recent adoption of Community legislation on Feed Hygiene, the information from the present study will contribute to appropriate measures adopted by the state to cope with EU laws on food and feed safety. Finally, the present information may be implemented for risk assessment by the European Food Safety Authority. CRUDE PROTEIN AND AMINO ACID ILEAL DIGESTIBILITY OF FIELD PEA SEEDS (PISUM SATIVUM L.) IN BROILERS DOTAS, V., PAPANIKOLAOU, K., HATZIPANAGIOTOU, A. and E. SOSSIDOU 1 Department of Animal Production, Faculty of Agriculture, Aristotle University of Thessaloniki, 541 24, Thessaloniki, Greece. 2 Veterinary Research Institute of Thessaloniki, N.AG.RE.F. SUMMARY An experiment was conducted to determine crude protein (CP) and amino acids (AAs) ileal digestibility of a local cultivar of field pea seeds (Pisum sativum L.) (FPS) in broiler chickens. Three experimental diets were used; a basal (B) and two others including FPS of the Greek cultivar “Olympos” at inclusion rates of either 150 or 300 g/kg, substituting equal amounts of maize starch. Hence, the differences in dietary CP and AAs concentrations resulted only from the inclusion of FPS. Chromium trioxide (Cr2O3) was included as an indigestible marker. Crude protein concentration in the complete diets ranged from 162 to 230 g/kg. All diets were fed ad libitum to broiler chickens between the age of 15 and 22 days. Six pens of 12 chickens each were randomly allocated into each treatment. Digesta were collected from all birds of each pen, from the section of the gastrointestinal tract between Meckel’s diverticulum and 2 cm anterior to the ileo-caeco-colonic junction. During the experimental seven-day period, mean feed intake of the basal diet was 53 g/bird/day, wherein it ranged from 57-62 g/bird/day and 61-67 g/bird/day for treatments with inclusion rates of FPS of 150 g/kg and 300 g/kg, respectively. Average body weight gain of the broilers was 173 g/bird for the basal diet and ranged from 282-335 g/bird and 337-364 g/bird for treatments containing 150 g/kg and 300 g/kg of FPS, respectively. The amounts of crude protein and AAs digested responded linearly to increased consumption while the relationships between consumed and digested amounts of AAs were determined by multiple linear regression using the slope for each one of them. Crude protein ileal digestibility of the diets showed a linear reduction by increasing inclusion rates of FPS from 0.87 for the basal diet to 0.81 and 0.78 for the diets containing 150 g/kg and 300 g/kg of FPS, respectively. A similar trend was noticed for the majority of AAs. The AAs of FPS with the highest values of ileal digestibility were, in decreasing order: arginine (0.92 ± 0.012), glutamic acid, lysine, methionine, phenylalanine and leucine, whereas those with the lowest values were cystine and valine (0.70 ± 0.022 and 0.72 ± 0.025, respectively). Ileal gross energy digestibility was similar between the basal diet and that which included FPS at the lower inclusion rate. To the contrary, the diet containing 300 g/kg of FPS had significantly (P<0.05) lower ileal digestibility than the other two (0.80 ± 0.014 and 0.78 ± 0.010 versus 0.072 ± 0.012 for the diets containing 0.150 or 300 g/kg of FPS, respectively). The multiple linear regression approach applied in this experiment was suitable for determining partial digestibilities in AAs of FPS without the need for consideration of basal endogenous AA secretions and losses.